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  • American Institute of Physics (AIP)  (241,953)
  • MDPI Publishing
  • 1
    Publication Date: 2018-08-13
    Description: Remote Sensing, Vol. 10, Pages 1271: Spectral and Spatial Classification of Hyperspectral Images Based on Random Multi-Graphs Remote Sensing doi: 10.3390/rs10081271 Authors: Feng Gao Qun Wang Junyu Dong Qizhi Xu Hyperspectral image classification has been acknowledged as the fundamental and challenging task of hyperspectral data processing. The abundance of spectral and spatial information has provided great opportunities to effectively characterize and identify ground materials. In this paper, we propose a spectral and spatial classification framework for hyperspectral images based on Random Multi-Graphs (RMGs). The RMG is a graph-based ensemble learning method, which is rarely considered in hyperspectral image classification. It is empirically verified that the semi-supervised RMG deals well with small sample setting problems. This kind of problem is very common in hyperspectral image applications. In the proposed method, spatial features are extracted based on linear prediction error analysis and local binary patterns; spatial features and spectral features are then stacked into high dimensional vectors. The high dimensional vectors are fed into the RMG for classification. By randomly selecting a subset of features to create a graph, the proposed method can achieve excellent classification performance. The experiments on three real hyperspectral datasets have demonstrated that the proposed method exhibits better performance than several closely related methods.
    Electronic ISSN: 2072-4292
    Topics: Architecture, Civil Engineering, Surveying , Geography
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  • 2
    Publication Date: 2018-08-13
    Description: Materials, Vol. 11, Pages 1413: Fused Particle Fabrication 3-D Printing: Recycled Materials’ Optimization and Mechanical Properties Materials doi: 10.3390/ma11081413 Authors: Aubrey L. Woern Dennis J. Byard Robert B. Oakley Matthew J. Fiedler Samantha L. Snabes Joshua M. Pearce Fused particle fabrication (FPF) (or fused granular fabrication (FGF)) has potential for increasing recycled polymers in 3-D printing. Here, the open source Gigabot X is used to develop a new method to optimize FPF/FGF for recycled materials. Virgin polylactic acid (PLA) pellets and prints were analyzed and were then compared to four recycled polymers including the two most popular printing materials (PLA and acrylonitrile butadiene styrene (ABS)) as well as the two most common waste plastics (polyethylene terephthalate (PET) and polypropylene (PP)). The size characteristics of the various materials were quantified using digital image processing. Then, power and nozzle velocity matrices were used to optimize the print speed, and a print test was used to maximize the output for a two-temperature stage extruder for a given polymer feedstock. ASTM type 4 tensile tests were used to determine the mechanical properties of each plastic when they were printed with a particle drive extruder system and were compared with filament printing. The results showed that the Gigabot X can print materials 6.5× to 13× faster than conventional printers depending on the material, with no significant reduction in the mechanical properties. It was concluded that the Gigabot X and similar FPF/FGF printers can utilize a wide range of recycled polymer materials with minimal post processing.
    Electronic ISSN: 1996-1944
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
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  • 3
    Publication Date: 2018-08-13
    Description: Materials, Vol. 11, Pages 1414: Numerical-Experimental Study of the Consolidation Phenomenon in the Selective Laser Melting Process with a Thermo-Fluidic Coupled Model Materials doi: 10.3390/ma11081414 Authors: Francisco Cordovilla Ángel García-Beltrán Miguel Garzón Diego A. Muñoz José L. Ocaña One of the main limiting factors for a widespread industrial use of the Selective Laser Melting Process it its lack of productivity, which restricts the use of this technology just for high added-value components. Typically, the thickness of the metallic powder that is used lies on the scale of micrometers. The use of a layer up to one millimeter would be necessarily associated to a dramatic increase of productivity. Nevertheless, when the layer thickness increases, the complexity of consolidation phenomena makes the process difficult to be governed. The present work proposes a 3D finite element thermo-coupled model to study the evolution from the metallic powder to the final consolidated material, analyzing specifically the movements and loads of the melt pool, and defining the behavior of some critical thermophysical properties as a function of temperature and the phase of the material. This model uses advanced numerical tools such as the Arbitrary Lagrangean–Eulerian formulation and the Automatic Remeshing technique. A series of experiments have been carried out, using a high thickness powder layer, allowing for a deeper understanding of the consolidation phenomena and providing a reference to compare the results of the numerical calculations.
    Electronic ISSN: 1996-1944
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
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  • 4
    Publication Date: 2018-08-13
    Description: Remote Sensing, Vol. 10, Pages 1269: Panoramic Image and Three-Axis Laser Scanner Integrated Approach for Indoor 3D Mapping Remote Sensing doi: 10.3390/rs10081269 Authors: Pengcheng Zhao Qingwu Hu Shaohua Wang Mingyao Ai Qingzhou Mao High-precision indoor three-dimensional maps are a prerequisite for building information models, indoor location-based services, etc., but the indoor mapping solution is still in the stage of technological experiment and application scenario development. In this paper, indoor mapping equipment integrating a three-axis laser scanner and panoramic camera is designed, and the corresponding workflow and critical technologies are described. First, hardware design and software for controlling the operations and calibration of the spatial relationship between sensors are completed. Then, the trajectory of the carrier is evaluated by a simultaneous location and mapping framework, which includes reckoning of the real-time position and attitude of the carrier by a filter fusing the horizontally placed laser scanner data and inertial measurement data, as well as the global optimization by a closed-loop adjustment using a graph optimization algorithm. Finally, the 3D point clouds and panoramic images of the scene are reconstructed from two tilt-mounted laser scanners and the panoramic camera by synchronization of the position and attitude of the carrier. The experiment was carried out in a five-story library using the proposed prototype system; the results demonstrate accuracies of up to 3 cm for 2D maps, and up to 5 cm for 3D maps, and the produced point clouds and panoramic images can be utilized for modeling and further works related to large-scale indoor scenes. Therefore, the proposed system is an efficient and accurate solution for indoor 3D mapping.
    Electronic ISSN: 2072-4292
    Topics: Architecture, Civil Engineering, Surveying , Geography
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  • 5
    Publication Date: 2018-08-13
    Description: Remote Sensing, Vol. 10, Pages 1270: Greening and Browning of the Hexi Corridor in Northwest China: Spatial Patterns and Responses to Climatic Variability and Anthropogenic Drivers Remote Sensing doi: 10.3390/rs10081270 Authors: Qingyu Guan Liqin Yang Ninghui Pan Jinkuo Lin Chuanqi Xu Feifei Wang Zeyu Liu The arid region of northwest China provides a unique terrestrial ecosystem to identify the response of vegetation activities to natural and anthropogenic changes. To reveal the influences of climate and anthropogenic factors on vegetation, the Normalized Difference Vegetation Index (NDVI), climate data, and land use and land cover change (LUCC) maps were used for this study. We analyzed the spatiotemporal change of NDVI during 2000–2015. A partial correlation analysis suggested that the contribution of precipitation (PRE) and temperature (TEM) on 95.43% of observed greening trends was 47% and 20%, respectively. The response of NDVI in the eastern section of the Qilian Mountains (ESQM) and the western section of the Qilian Mountains (WSQM) to PRE and TEM showed opposite trends. The multiple linear regressions used to quantify the contribution of anthropogenic activity on the NDVI trend indicated that the ESQM and oasis areas were mainly affected by anthropogenic activities (26%). The observed browning trend in the ESQM was attributed to excessive consumption of natural resources. A buffer analysis and piecewise regression methods were further applied to explore the influence of urbanization on NDVI and its change rate. The study demonstrated that urbanization destroys the vegetation cover within the developed city areas and extends about 4 km beyond the perimeter of urban areas and the NDVI of buffer cities (counties) in the range of 0–4 km (0–3 km) increased significantly. In the range of 5–15 (4–10) km (except for Jiayuguan), climate factors were the major drivers of a slight downtrend in the NDVI. The relationship of land use change and NDVI trends showed that construction land, urban settlement, and farmland expanded sharply by 171.43%, 60%, and 10.41%, respectively. It indicated that the rapid process of urbanization and coordinated urban-rural development shrunk ecosystem services.
    Electronic ISSN: 2072-4292
    Topics: Architecture, Civil Engineering, Surveying , Geography
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  • 6
    Publication Date: 2018-08-13
    Description: Sensors, Vol. 18, Pages 2640: Spatial Extension of Road Traffic Sensor Data with Artificial Neural Networks Sensors doi: 10.3390/s18082640 Authors: Mariano Gallo Giuseppina De Luca This paper proposes a method for estimating traffic flows on some links of a road network knowing the data on other links that are monitored with sensors. In this way, it is possible to obtain more information on traffic conditions without increasing the number of monitored links. The proposed method is based on artificial neural networks (ANNs), wherein the input data are the traffic flows on some monitored road links and the output data are the traffic flows on some unmonitored links. We have implemented and tested several single-layer feed-forward ANNs that differ in the number of neurons and the method of generating datasets for training. The proposed ANNs were trained with a supervised learning approach where input and output example datasets were generated through traffic simulation techniques. The proposed method was tested on a real-scale network and gave very good results if the travel demand patterns were known and used for generating example datasets, and promising results if the demand patterns were not considered in the procedure. Numerical results have underlined that the ANNs with few neurons were more effective than the ones with many neurons in this specific problem.
    Electronic ISSN: 1424-8220
    Topics: Chemistry and Pharmacology , Electrical Engineering, Measurement and Control Technology
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  • 7
    Publication Date: 2018-08-13
    Description: Sensors, Vol. 18, Pages 2643: Galfenol Thin Films and Nanowires Sensors doi: 10.3390/s18082643 Authors: Bethanie J. H. Stadler Madhukar Reddy Rajneeta Basantkumar Patrick McGary Eliot Estrine Xiaobo Huang Sang Yeob Sung Liwen Tan Jia Zou Mazin Maqableh Daniel Shore Thomas Gage Joseph Um Matthew Hein Anirudh Sharma Galfenol (Fe1−xGax, 10 < x < 40) may be the only smart material that can be made by electrochemical deposition which enables thick film and nanowire structures. This article reviews the deposition, characterization, and applications of Galfenol thin films and nanowires. Galfenol films have been made by sputter deposition as well as by electrochemical deposition, which can be difficult due to the insolubility of gallium. However, a stable process has been developed, using citrate complexing, a rotating disk electrode, Cu seed layers, and pulsed deposition. Galfenol thin films and nanowires have been characterized for crystal structures and magnetostriction both by our group and by collaborators. Films and nanowires have been shown to be largely polycrystalline, with magnetostrictions that are on the same order of magnitude as textured bulk Galfenol. Electrodeposited Galfenol films were made with epitaxial texture on GaAs. Galfenol nanowires have been made by electrodeposition into anodic aluminum oxide templates using similar parameters defined for films. Segmented nanowires of Galfenol/Cu have been made to provide engineered magnetic properties. Applications of Galfenol and other magnetic nanowires include microfluidic sensors, magnetic separation, cellular radio-frequency identification (RFID) tags, magnetic resonance imaging (MRI) contrast, and hyperthermia.
    Electronic ISSN: 1424-8220
    Topics: Chemistry and Pharmacology , Electrical Engineering, Measurement and Control Technology
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  • 8
    Publication Date: 2018-08-13
    Description: Sensors, Vol. 18, Pages 2644: Effects of the Ground Resolution and Thresholding on Crack Width Measurements Sensors doi: 10.3390/s18082644 Authors: Cho Yoon Jung When diagnosing the condition of a structure, it is necessary to measure the widths of any existing cracks in the structure. To ensure safety when relying on images of cracks, the selected imaging parameters and processing technology must be well understood. In this study, the effects of the ground sample distance and threshold values on the crack width measurement error are analyzed from a theoretical perspective. Here, the main source of such errors is assumed to be due to the mixed pixel phenomena in the left and right boundary pixels. Thus, a mathematical model is proposed in which the intensity changes in these pixels are computed via an equation. In addition, the relationship between the error and error probability distribution is represented with an equation based on the threshold values and mean error. Upon analysis, it was found that the threshold value that minimizes the error is at the mid-point between the background and foreground, and the probabilistic nature of the error indicates that it is theoretically possible to predict both the error and its probability distribution. The proposed model was validated using artificial images.
    Electronic ISSN: 1424-8220
    Topics: Chemistry and Pharmacology , Electrical Engineering, Measurement and Control Technology
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  • 9
    Publication Date: 2018-09-04
    Description: Sustainability, Vol. 10, Pages 3131: The Main Agroecological Structure (MAS) of the Agroecosystems: Concept, Methodology and Applications Sustainability doi: 10.3390/su10093131 Authors: Tomás Enrique León-Sicard Javier Toro Calderón Liven Fernando Martínez-Bernal José Alejandro Cleves-Leguízamo This document presents the concept of the Main Agroecological Structure of agroecosystems (MAS) from the perspective of environmental thinking (ecosystem-culture relationships) and considered as a dissipative cultural structure. It discusses the possible applications of this concept (resilience, production, diversity) both inside and outside the farms. The potential MAS can be useful in the planning processes of the farms because it allows the quantification of the internal and external corridors, including natural vegetation. At the same time, it can be an important tool in the context of landscape management because it shows a series of cultural relations (economic, social, symbolic and technological) that are normally overlooked by the partial analysis of landscape ecology.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 10
    Publication Date: 2018-09-04
    Description: Sustainability, Vol. 10, Pages 3130: Fraud, Economic versus Social-Psychological Losses, and Sustainable E-Auction Sustainability doi: 10.3390/su10093130 Authors: Xiaobing Zhang Fu-Sheng Tsai Chih-Chen Lin Ya-Fang Cheng Kun-Hwa Lu As compared to the economic losses, social and psychological losses are of equal importance in discussing the losses when encountering fraud. Taking advantage of a perspective paper form (i.e., free writing style with a mix of description, analysis, and comments) with in-depth discussions and well-developed propositions, we combine considerations from the knowledge gap, platform quality, and risk management to discuss the comparative seriousness of different fraud-caused losses. The conceptual model mainly articulates on a series of relationships among different degrees of knowledge gap, platform quality, and risk management in predicting the various combinative losses in the economic, social, and psychological aspects. Propositions follow. First, when the knowledge gap is higher, the economic losses of being cheated on the internet will be higher, while lower in social and psychological losses. Second, when perceived platform quality is higher, the economic losses of being cheated on the internet will be lower, while higher in social and psychological losses. Third, when platform risk management is better, all aspects of being cheated on the internet will be lower. Based on the assumption of network externality, we also argue that the multiple dimensions of fraud-caused losses may damage e-auction sustainability. Theoretical and practical implications will be discussed.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 11
    Publication Date: 2018-09-04
    Description: Symmetry, Vol. 10, Pages 379: Effective Blind Frequency Offset Estimation Scheme for BST-OFDM Based HDTV Broadcast Systems Symmetry doi: 10.3390/sym10090379 Authors: Yong-An Jung Young-Hwan You The integrated services digital broadcasting-terrestrial (ISDB-T) system is designed in order to accommodate high-quality video/audio and multimedia services, using band segmented transmission orthogonal frequency division multiplexing (BST-OFDM) scheme. In the ISDB-T system, the pilot configuration varies depending on whether a segment uses a coherent or differential modulation. Therefore, it is necessary to perform a joint estimation of carrier frequency offset (CFO) and sampling frequency offset (SFO) independent of the segment format in the ISDB-T system. The goal is to complete those synchronization tasks while considering an information-carrying transmission and multiplexing configuration control (TMCC) signal as pilot symbols. It is demonstrated through numerical simulations that the differential BPSK-modulated TMCC information can be efficiently used for a least-squares estimation of CFO and SFO, offering an acceptable performance.
    Electronic ISSN: 2073-8994
    Topics: Mathematics , Physics
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  • 12
    Publication Date: 2018-09-04
    Description: Water, Vol. 10, Pages 1179: The Influence of Groundwater on the Sliding and Deposition Behaviors of Cataclinal Slopes Water doi: 10.3390/w10091179 Authors: Cheng-Hsueh Weng Ming-Lang Lin Chia-Ming Lo Hsi-Hung Lin In 2015, Typhoon Soudelor caused a number of slopes to collapse in Wulai District of New Taipei City. One of these landslides took place in the village of Zhongzhi and involved atypical cataclinal slope failure with a rock–soil interface. The remaining rock in the slope and the rock that originally covered it contained vertical joints, so groundwater could have flowed through the joints and influenced landslide behavior. However, few existing studies have examined the influence of upward groundwater flow on slope stability. To fill this gap, this study used physical tests and discrete element method software to conduct relevant investigations. We first conducted tests using the ground water flow and cataclinal slope simulator, in which water can flow out of holes in the platform to simulate upward-seeping groundwater. We used gypsum boards or rhombus-shaped grinding stones to simulate rock with vertical joints and round grinding stones mixed in paste to simulate cohesive regolith. The objective of the tests was to understand the influence of water flow on the landslide behavior of the specimens and the connections between movement behavior and the sequence of sliding between different materials during the landslide. We then reproduced the physical tests using discrete element method software PFC3D (Particle Flow Code 3D Version 4.0 by Itasca, Minneapolis, MN, USA) to display the influence of water flow on specimens, including the weakening of bond strength, decreasing coefficient of friction between particles, and the application of seepage force, as well as uplift and lateral forces caused by water pressure. This process gave us an understanding of the influence of different groundwater conditions on landslide behavior, which facilitates the study of landslide mechanisms and movement behavior. Finally, we applied the water flow influence settings to simulate and examine the Zhongzhi landslide process. Compared to methods that simply reduce the friction coefficients to trigger landslides, our numerical simulation was closer to reality in that in this case a rising water table triggered the landslide.
    Electronic ISSN: 2073-4441
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 13
    Publication Date: 2018-09-04
    Description: Water, Vol. 10, Pages 1178: Recent Trends (2012–2016) of N, Si, and P Export from the Nemunas River Watershed: Loads, Unbalanced Stoichiometry, and Threats for Downstream Aquatic Ecosystems Water doi: 10.3390/w10091178 Authors: Irma Vybernaite-Lubiene Mindaugas Zilius Laura Saltyte-Vaisiauske Marco Bartoli The Curonian Lagoon, the largest in Europe, suffers from nuisance cyanobacterial blooms during summer, probably triggered by unbalanced nutrient availability. However, nutrient delivery to this system was never analysed in detail. During 2012–2016, we analysed the monthly discharge, nutrient loads, and ecological stoichiometry at the closing section of the Nemunas River, the main nutrient source to the lagoon. The aim of this study was to investigate seasonal and annual variations of nitrogen (N), silica (Si), and phosphorous (P) with respect to discharge, climatic features, and historical trends. The nutrient loads varied yearly by up to 50% and their concentrations underwent strong seasonality, with summer N and Si limitation. The river discharge (16 ± 4 km3·yr−1) was lower than the historical average (21.8 km3·yr−1). Changes in agricultural practices resulted in similar N export from the river watershed compared to historical data (1986–2002), while sewage treatment plant improvements led to a ~60% decrease of P loads. This work contributes new data to the scattered available information on the most important nutrient source to the Curonian Lagoon. Further P reduction is needed to avoid unbalanced dissolved inorganic nitrogen and phosphorus (DIN:DIP~10) ecological stoichiometry in summer, which may stimulate undesired cyanobacterial blooms.
    Electronic ISSN: 2073-4441
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 14
    Publication Date: 2018-09-04
    Description: Symmetry, Vol. 10, Pages 378: Applications of Differential Form Wu’s Method to Determine Symmetries of (Partial) Differential Equations Symmetry doi: 10.3390/sym10090378 Authors: Temuer Chaolu Sudao Bilige In this paper, we present an application of Wu’s method (differential characteristic set (dchar-set) algorithm) for computing the symmetry of (partial) differential equations (PDEs) that provides a direct and systematic procedure to obtain the classical and nonclassical symmetry of the differential equations. The fundamental theory and subalgorithms used in the proposed algorithm consist of a different version of the Lie criterion for the classical symmetry of PDEs and the zero decomposition algorithm of a differential polynomial (d-pol) system (DPS). The version of the Lie criterion yields determining equations (DTEs) of symmetries of differential equations, even those including a nonsolvable equation. The decomposition algorithm is used to solve the DTEs by decomposing the zero set of the DPS associated with the DTEs into a union of a series of zero sets of dchar-sets of the system, which leads to simplification of the computations.
    Electronic ISSN: 2073-8994
    Topics: Mathematics , Physics
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  • 15
    Publication Date: 2018-09-04
    Description: Symmetry, Vol. 10, Pages 377: The Absolute Ruin Insurance Risk Model with a Threshold Dividend Strategy Symmetry doi: 10.3390/sym10090377 Authors: Wenguang Yu Yujuan Huang Chaoran Cui The absolute ruin insurance risk model is modified by including some valuable market economic information factors, such as credit interest, debit interest and dividend payments. Such information is especially important for insurance companies to control risks. We further assume that the insurance company is able to finance and continue to operate when its reserve is negative. We investigate the integro-differential equations for some interest actuarial diagnostics. We also provide numerical examples to explain the effects of relevant parameters on actuarial diagnostics.
    Electronic ISSN: 2073-8994
    Topics: Mathematics , Physics
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  • 16
    Publication Date: 2018-09-04
    Description: Water, Vol. 10, Pages 1177: Investigating the Dynamic Influence of Hydrological Model Parameters on Runoff Simulation Using Sequential Uncertainty Fitting-2-Based Multilevel-Factorial-Analysis Method Water doi: 10.3390/w10091177 Authors: Shuai Zhou Yimin Wang Jianxia Chang Aijun Guo Ziyan Li Hydrological model parameters are generally considered to be simplified representations that characterize hydrologic processes. Therefore, their influence on runoff simulations varies with climate and catchment conditions. To investigate the influence, a three-step framework is proposed, i.e., a Latin hypercube sampling (LHS-OAT) method multivariate regression model is used to conduct parametric sensitivity analysis; then, the multilevel-factorial-analysis method is used to quantitatively evaluate the individual and interactive effects of parameters on the hydrologic model output. Finally, analysis of the reasons for dynamic parameter changes is performed. Results suggest that the difference in parameter sensitivity for different periods is significant. The soil bulk density (SOL_BD) is significant at all times, and the parameter Soil Convention Service (SCS) runoff curve number (CN2) is the strongest during the flood period, and the other parameters are weaker in different periods. The interaction effects of CN2 and SOL_BD, as well as effective hydraulic channel conditions (CH_K2) and SOL_BD, are obvious, indicating that soil bulk density can impact the amount of loss generated by surface runoff and river recharge to groundwater. These findings help produce the best parameter inputs and improve the applicability of the model.
    Electronic ISSN: 2073-4441
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 17
    Publication Date: 2018-08-14
    Description: Energies, Vol. 11, Pages 2107: Optimal P-Q Control of Grid-Connected Inverters in a Microgrid Based on Adaptive Population Extremal Optimization Energies doi: 10.3390/en11082107 Authors: Min-Rong Chen Huan Wang Guo-Qiang Zeng Yu-Xing Dai Da-Qiang Bi The optimal P-Q control issue of the active and reactive power for a microgrid in the grid-connected mode has attracted increasing interests recently. In this paper, an optimal active and reactive power control is developed for a three-phase grid-connected inverter in a microgrid by using an adaptive population-based extremal optimization algorithm (APEO). Firstly, the optimal P-Q control issue of grid-connected inverters in a microgrid is formulated as a constrained optimization problem, where six parameters of three decoupled PI controllers are real-coded as the decision variables, and the integral time absolute error (ITAE) between the output and referenced active power and the ITAE between the output and referenced reactive power are weighted as the objective function. Then, an effective and efficient APEO algorithm with an adaptive mutation operation is proposed for solving this constrained optimization problem. The simulation and experiments for a 3kW three-phase grid-connected inverter under both nominal and variable reference active power values have shown that the proposed APEO-based P-Q control method outperforms the traditional Z-N empirical method, the adaptive genetic algorithm-based, and particle swarm optimization-based P-Q control methods.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 18
    Publication Date: 2018-08-14
    Description: Energies, Vol. 11, Pages 2104: Online Energy Management and Heterogeneous Task Scheduling for Smart Communities with Residential Cogeneration and Renewable Energy Energies doi: 10.3390/en11082104 Authors: Yongsheng Cao Guanglin Zhang Demin Li Lin Wang Zongpeng Li With the development of renewable energy technology and communication technology in recent years, many residents now utilize renewable energy devices in their residences with energy storage systems. We have full confidence in the promising prospects of sharing idle energy with others in a community. However, it is a great challenge to share residents’ energy with others in a community to minimize the total cost of all residents. In this paper, we study the problem of energy management and task scheduling for a community with renewable energy and residential cogeneration, such as residential combined heat and power system (resCHP) to pay the least electricity bill. We take elastic and inelastic load demands into account which are delay intolerant and delay tolerant tasks in the community. The minimum cost problem of a non-cooperative community is extracted into a random non-convex optimization problem with some physical constraints. Our objective is to minimize the time-average cost for each resident in the community, including the cost of the external grid and natural gas. The Lyapunov optimization theory and a primal-dual gradient method are adopted to tackle this problem, which needs no future data and has low computational complexity. Furthermore, we design a cooperative renewable energy sharing algorithm based on State-action-reward-state-action (Sarsa) Algorithm, in the condition that each residence in the community is able to communicate with its neighbors by a central controller. Finally, extensive simulations are presented to validate the proposed algorithms by using practical data.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 19
    Publication Date: 2018-08-14
    Description: Energies, Vol. 11, Pages 2105: SOLIS—A Novel Decision Support Tool for the Assessment of Solar Radiation in ArcGIS Energies doi: 10.3390/en11082105 Authors: Jan K. Kazak Małgorzata Świąder The global Sustainable Development Goals influence the implementation of energy development strategies worldwide. However, in order to support local stakeholders in sustainable energy development strategies and climate change adaptation plans and the implementation of policies, there is a need to equip local decision makers with tools enabling the assessment of sustainable energy investments. In order to do so, the aim of this study is to create a novel tool for the assessment of solar radiation (SOLIS) in ArcGIS. The SOLIS tool builds on the existing ArcGIS algorithm by including input data conversion and post-processing of the results. This should expand the group of potential users of solar radiation analyses. The self-filtering tool excludes surfaces that are not suitable for solar energy investments due to geometrical reasons. The reduction of the size of the output data is positive for technical reasons (speed of the calculation and occupied storage place) and for cognitive reasons (reduction of the number of objects necessary to analyse by the user). The SOLIS tool limits the requirement for users to insert three-dimensional (3D) models of roofs (with any geometry) and select solar radiation calculation periods. The highlight of this research is to develop the decision support tool for the assessment of solar radiation, which would reduce the requirements for potential users, in order to promote indicator-based assessments among non-Geographical Information Systems (GIS) specialists.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 20
    Publication Date: 2018-08-14
    Description: Energies, Vol. 11, Pages 2103: A Study on the Fuel Economy Potential of Parallel and Power Split Type Hybrid Electric Vehicles Energies doi: 10.3390/en11082103 Authors: Hyunhwa Kim Junbeom Wi Jiho Yoo Hanho Son Chiman Park Hyunsoo Kim What is the best number of gear steps for parallel type hybrid electric vehicles (HEVs) and what are the pros and cons of the power split type HEV compared to the parallel type have been interesting issues in the development of HEVs. In this study, a comparative analysis was performed to evaluate the fuel economy potential of a parallel HEV and a power split type HEV. First, the fuel economy potential of the parallel HEV was investigated for the number of gear steps. Four-speed, six-speed, and eight-speed automatic transmissions (ATs) and a continuously variable transmission (CVT) were selected, and their drivetrain losses were considered in the dynamic programming (DP). It was found from DP results that the power electronics system (PE) loss decreased because the magnitude of the motor load leveling power decreased as the number of gear steps increased. On the other hand, the drivetrain losses including the electric oil pump (EOP) loss increased with increasing gear step. The improvement rate from the 4-speed to the 6-speed was the greatest, while it decreased for the higher gear step. The fuel economy of the CVT HEV was rather low due to the large EOP loss in spite of the reduced PE loss. In addition, the powertrain characteristics of the parallel HEV were compared with the power split type HEV. In the power split type HEV, the PE loss was almost double compared to that of the parallel HEV because two large capacity motor-generators were used. However, the drivetrain loss and EOP loss of the power split type HEV were found to be much smaller due to its relatively simple architecture. It is expected that the power characteristics of the parallel and power split type HEVs obtained from the DP results can be used in the development of HEV systems.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 21
    Publication Date: 2018-08-14
    Description: Energies, Vol. 11, Pages 2102: Electromechanical Transient Modeling of Line Commutated Converter-Modular Multilevel Converter-Based Hybrid Multi-Terminal High Voltage Direct Current Transmission Systems Energies doi: 10.3390/en11082102 Authors: Liang Xiao Yan Li Huangqing Xiao Zheren Zhang Zheng Xu A method for electromechanical modeling of line commutated converter (LCC)-modular multilevel converter (MMC)-based hybrid multi-terminal High Voltage Direct Current Transmission (HVDC) systems for large-scale power system transient stability study is proposed. Firstly, the general idea of modeling the LCC-MMC hybrid multi-terminal HVDC system is presented, then the AC-side and DC-side models of the LCC/MMC are established. Different from the conventional first-order DC-side model of the MMC, an improved second-order DC-side model of the MMC is established. Besides considering the firing angle limit of the LCC, a sequential power flow algorithm is proposed for the initialization of LCC-MMC hybrid multi-terminal HVDC system. Lastly, simulations of small scale and large scale power systems embedded with a three-terminal LCC-MMC hybrid HVDC system are performed on the electromechanical simulation platform PSS/E. It is demonstrated that if the firing angle limit is not considered, the accuracy of the power flow solutions will be greatly affected. Steady state calculation and dynamic simulation show that the developed LCC-MMC hybrid MTDC model is accurate enough for electromechanical transient stability studies of large-scale AC/DC system.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 22
    Publication Date: 2018-08-14
    Description: Energies, Vol. 11, Pages 2100: A Novel Computational Approach for Harmonic Mitigation in PV Systems with Single-Phase Five-Level CHBMI Energies doi: 10.3390/en11082100 Authors: Rosario Miceli Giuseppe Schettino Fabio Viola In this paper, a novel approach to low order harmonic mitigation in fundamental switching frequency modulation is proposed for high power photovoltaic (PV) applications, without trying to solve the cumbersome non-linear transcendental equations. The proposed method allows for mitigation of the first-five harmonics (third, fifth, seventh, ninth, and eleventh harmonics), to reduce the complexity of the required procedure and to allocate few computational resource in the Field Programmable Gate Array (FPGA) based control board. Therefore, the voltage waveform taken into account is different respect traditional voltage waveform. The same concept, known as “voltage cancelation”, used for single-phase cascaded H-bridge inverters, has been applied at a single-phase five-level cascaded H-bridge multilevel inverter (CHBMI). Through a very basic methodology, the polynomial equations that drive the control angles were detected for a single-phase five-level CHBMI. The acquired polynomial equations were implemented in a digital system to real-time operation. The paper presents the preliminary analysis in simulation environment and its experimental validation.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 23
    Publication Date: 2018-08-14
    Description: Energies, Vol. 11, Pages 2098: Analysis of Shallow Subsurface Geological Structures and Ground Effective Thermal Conductivity for the Evaluation of Ground-Source Heat Pump System Installation in the Aizu Basin, Northeast Japan Energies doi: 10.3390/en11082098 Authors: Takeshi Ishihara Gaurav Shrestha Shohei Kaneko Youhei Uchida Shallow subsurface geological structure mapping combined with ground effective thermal conductivity values at the basin scale provide an appropriate method to evaluate the installation potential of ground-source heat pump systems. This study analyzed the geological structure of the Aizu Basin (Northeast Japan) using sedimentary cores and boring log and mapped the distribution of average ground effective thermal conductivity in the range from −10 m to −100 m depth calculated from cores and logs. Gravel layers dominate in alluvial fans of the northern and southern basin areas, which are found to be associated with higher average ground effective thermal conductivity values, 1.3–1.4 W/m/K, while central and western floodplain areas show lower values of 1.0–1.3 W/m/K due to the existence of thick mud layers in the shallow subsurface. The results indicate that the conventional closed-loop systems are more feasible in northern and southern basin areas than in the central and western areas. Evaluation for the installation potential of the ground-source heat pump systems using depth-based distribution maps of average ground effective thermal conductivity is the originality of this study. This approach is valuable and proper for the simple assessment of the system installation in different sedimentary plains and basins in Japan and other countries.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 24
    Publication Date: 2018-08-14
    Description: Energies, Vol. 11, Pages 2097: Prediction of Wave Power Generation Using a Convolutional Neural Network with Multiple Inputs Energies doi: 10.3390/en11082097 Authors: Chenhua Ni Xiandong Ma Successful development of a marine wave energy converter (WEC) relies strongly on the development of the power generation device, which needs to be efficient and cost-effective. An innovative multi-input approach based on the Convolutional Neural Network (CNN) is investigated to predict the power generation of a WEC system using a double-buoy oscillating body device (OBD). The results from the experimental data show that the proposed multi-input CNN performs much better at predicting results compared with the conventional artificial network and regression models. Through the power generation analysis of this double-buoy OBD, it shows that the power output has a positive correlation with the wave height when it is higher than 0.2 m, which becomes even stronger if the wave height is higher than 0.6 m. Furthermore, the proposed approach associated with the CNN algorithm in this study can potentially detect the changes that could be due to presence of anomalies and therefore be used for condition monitoring and fault diagnosis of marine energy converters. The results are also able to facilitate controlling of the electricity balance among energy conversion, wave power produced and storage.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 25
    Publication Date: 2018-08-14
    Description: Entropy, Vol. 20, Pages 600: Identity Vector Extraction by Perceptual Wavelet Packet Entropy and Convolutional Neural Network for Voice Authentication Entropy doi: 10.3390/e20080600 Authors: Lei Lei Kun She Recently, the accuracy of voice authentication system has increased significantly due to the successful application of the identity vector (i-vector) model. This paper proposes a new method for i-vector extraction. In the method, a perceptual wavelet packet transform (PWPT) is designed to convert speech utterances into wavelet entropy feature vectors, and a Convolutional Neural Network (CNN) is designed to estimate the frame posteriors of the wavelet entropy feature vectors. In the end, i-vector is extracted based on those frame posteriors. TIMIT and VoxCeleb speech corpus are used for experiments and the experimental results show that the proposed method can extract appropriate i-vector which reduces the equal error rate (EER) and improve the accuracy of voice authentication system in clean and noisy environment.
    Electronic ISSN: 1099-4300
    Topics: Chemistry and Pharmacology , Physics
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  • 26
    Publication Date: 2018-08-14
    Description: Entropy, Vol. 20, Pages 601: A Maximum-Entropy Method to Estimate Discrete Distributions from Samples Ensuring Nonzero Probabilities Entropy doi: 10.3390/e20080601 Authors: Paul Darscheid Anneli Guthke Uwe Ehret When constructing discrete (binned) distributions from samples of a data set, applications exist where it is desirable to assure that all bins of the sample distribution have nonzero probability. For example, if the sample distribution is part of a predictive model for which we require returning a response for the entire codomain, or if we use Kullback–Leibler divergence to measure the (dis-)agreement of the sample distribution and the original distribution of the variable, which, in the described case, is inconveniently infinite. Several sample-based distribution estimators exist which assure nonzero bin probability, such as adding one counter to each zero-probability bin of the sample histogram, adding a small probability to the sample pdf, smoothing methods such as Kernel-density smoothing, or Bayesian approaches based on the Dirichlet and Multinomial distribution. Here, we suggest and test an approach based on the Clopper–Pearson method, which makes use of the binominal distribution. Based on the sample distribution, confidence intervals for bin-occupation probability are calculated. The mean of each confidence interval is a strictly positive estimator of the true bin-occupation probability and is convergent with increasing sample size. For small samples, it converges towards a uniform distribution, i.e., the method effectively applies a maximum entropy approach. We apply this nonzero method and four alternative sample-based distribution estimators to a range of typical distributions (uniform, Dirac, normal, multimodal, and irregular) and measure the effect with Kullback–Leibler divergence. While the performance of each method strongly depends on the distribution type it is applied to, on average, and especially for small sample sizes, the nonzero, the simple “add one counter”, and the Bayesian Dirichlet-multinomial model show very similar behavior and perform best. We conclude that, when estimating distributions without an a priori idea of their shape, applying one of these methods is favorable.
    Electronic ISSN: 1099-4300
    Topics: Chemistry and Pharmacology , Physics
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  • 27
    Publication Date: 2018-08-14
    Description: Entropy, Vol. 20, Pages 603: Symmetry, Outer Bounds, and Code Constructions: A Computer-Aided Investigation on the Fundamental Limits of Caching Entropy doi: 10.3390/e20080603 Authors: Chao Tian We illustrate how computer-aided methods can be used to investigate the fundamental limits of the caching systems, which are significantly different from the conventional analytical approach usually seen in the information theory literature. The linear programming (LP) outer bound of the entropy space serves as the starting point of this approach; however, our effort goes significantly beyond using it to prove information inequalities. We first identify and formalize the symmetry structure in the problem, which enables us to show the existence of optimal symmetric solutions. A symmetry-reduced linear program is then used to identify the boundary of the memory-transmission-rate tradeoff for several small cases, for which we obtain a set of tight outer bounds. General hypotheses on the optimal tradeoff region are formed from these computed data, which are then analytically proven. This leads to a complete characterization of the optimal tradeoff for systems with only two users, and certain partial characterization for systems with only two files. Next, we show that by carefully analyzing the joint entropy structure of the outer bounds for certain cases, a novel code construction can be reverse-engineered, which eventually leads to a general class of codes. Finally, we show that outer bounds can be computed through strategically relaxing the LP in different ways, which can be used to explore the problem computationally. This allows us firstly to deduce generic characteristic of the converse proof, and secondly to compute outer bounds for larger problem cases, despite the seemingly impossible computation scale.
    Electronic ISSN: 1099-4300
    Topics: Chemistry and Pharmacology , Physics
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  • 28
    Publication Date: 2018-08-14
    Description: Forests, Vol. 9, Pages 493: Spatio-Temporal Dynamic Architecture of Living Brush Mattress: Root System and Soil Shear Strength in Riverbanks Forests doi: 10.3390/f9080493 Authors: Dong Zhang Jinhua Cheng Ying Liu Hongjiang Zhang Lan Ma Xuemei Mei Yihui Sun As a basal measure of soil bioengineering, the living brush mattress has been widely applied in riparian ecological protection forest construction. The living brush mattress shows favorable protective effects on riverbanks. However, there are few reports on the root structure and the soil strengthening benefit of the living brush mattress. The present work reports a series of experiments on root morphology and soil shear strength enhancement at the temporal and spatial scales. The object of the study is 24 living brush mattress trees constructed with Salix alba L. ‘Tristis’ (LBS hereafter). Traditional root morphology and mechanical measurement methods were used to collect the parameters. The results showed that the root systems of LBS had the characteristics of symmetry and upslope growth. The roots were mainly distributed in a cylindrical region of the soil (radius × thickness: 0.4 m × 0.5 m) and their biomass increased with different growth rates for the periods from 1 to 5 and from 5 to 7 years. Both age and slope position were factors that influence root growth. The root diameter falls within 0–5 mm, has a significant effect on the soil shear strength and provides a conical-shape potentiation zone to ensure the efficient protection of a riverbank. The results of this study demonstrate that LBS is an efficient and feasible engineering measure in the field of riverbank protection.
    Electronic ISSN: 1999-4907
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
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  • 29
    Publication Date: 2018-09-04
    Description: Materials, Vol. 11, Pages 1595: An Analytical Study of Electromagnetic Deep Penetration Conditions and Implications in Lossy Media through Inhomogeneous Waves Materials doi: 10.3390/ma11091595 Authors: Paolo Baccarelli Fabrizio Frezza Patrizio Simeoni Nicola Tedeschi This paper illustrates how the penetration of electromagnetic waves in lossy media strongly depends on the waveform and not only on the media involved. In particular, the so-called inhomogeneous plane waves are compared against homogeneous plane waves illustrating how the first ones can generate deep penetration effects. Moreover, the paper provides examples showing how such waves may be practically generated. The approach taken here is analytical and it concentrates on the deep penetration conditions obtained by means of incident inhomogeneous plane waves incoming from a lossless medium and impinging on a lossy medium. Both conditions and constraints that the waveforms need to possess to achieve deep penetration are analysed. Some results are finally validated through numerical computations. The theory presented here is of interest in view of a practical implementation of the deep penetration effect.
    Electronic ISSN: 1996-1944
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
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  • 30
    Publication Date: 2018-09-04
    Description: Materials, Vol. 11, Pages 1593: Study on Formation Process and Models of Linear Fe Cluster Structure on a Si(111)-7 × 7-CH3OH Surface Materials doi: 10.3390/ma11091593 Authors: Wenxin Li Wanyu Ding Dongying Ju Ken-ichi Tanaka Fumio Komori STM results showed that Fe atoms were deposited on a Si(111)-7 × 7 reconstructed surface, which was saturated with CH3OH molecules. Fe atomic linear structure was composed of stable clusters and in-situ observed by the scanning tunneling microscopy (STM). The aim to improve its application of magnetic memory material, both formation process and models, has been explored in this paper. By combining surface images and mass spectrometer data, an intermediate layer model was established. In terms of thermal stability, the most favorable adsorption sites of CH3OH were further explored. After that, Fe atoms were deposited on the Si(111)-7 × 7-CH3OH surface, forming a linear cluster structure. On the one hand, a new Fe cluster model was put forward in this paper, which was established with height measurement and 3D surface display technology. This model is also affected by the evaporation temperature, which can be consistent with the atomic stacking pattern of face centered cubic structures. On the other hand, the slight height change suggested the stability of linear structures. Even in the condition of thin air introduction, Fe cluster showed a good performance, which suggested the possibility of magnetic memory application in the future. These investigations are believed to have, to a certain extent, increased the probability of forming Fe linear clusters on the surface of silicon substrate, especially according to the models and surface technology we adjusted.
    Electronic ISSN: 1996-1944
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
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  • 31
    Publication Date: 2018-09-04
    Description: Minerals, Vol. 8, Pages 381: Effects of Superplasticizer on the Hydration, Consistency, and Strength Development of Cemented Paste Backfill Minerals doi: 10.3390/min8090381 Authors: Jian Zhang Hongwei Deng Abbas Taheri Junren Deng Bo Ke The strength and consistency of cemented paste backfill (CPB) are of key concerns in the stope stability and cost control for underground mines. It is common practice to use additives, such as superplasticizer, to improve the performance of CPB. This study mainly focuses on the effects of superplasticizer on the hydration, consistency, and strength of CPB. In this study, a polynaphtalene sulfonate was used as the superplasticizer. The binder is a mix of 33.3% ordinary Portland cement and 66.7% fly ash. The CPB specimens with a tailings-binder ratio of 3:1 and a solid concentration of 70% were then tested by a low field nuclear magnetic resonance system after different hydration times. Effects of polynaphtalene sulfonate on the hydration, fluidity, and strength were investigated. Results showed that the polynaphtalene sulfonate has a strong influence on short-duration hydration, which may contribute to the strength increase of CPB. It has been demonstrated that the polynaphtalene sulfonate improved the fluidity of the CPB mixture. With the increased dosage of polynaphtalene sulfonate, the slump increased. It was also found that the polynaphtalene sulfonate dosage has a negligible effect on the 1 day (d) strength while it has a strengthening effect on the 7 d, 14 d, and 28 d strength of CPB specimens.
    Electronic ISSN: 2075-163X
    Topics: Geosciences
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  • 32
    Publication Date: 2018-09-05
    Description: Remote Sensing, Vol. 10, Pages 1406: JAXA High-Resolution Land Use/Land Cover Map for Central Vietnam in 2007 and 2017 Remote Sensing doi: 10.3390/rs10091406 Authors: Phan Cao Duong Ta Hoang Trung Kenlo Nishida Nasahara Takeo Tadono Robust remote monitoring of land cover changes is essential for a range of studies such as climate modeling, ecosystems, and environmental protection. However, since each satellite data has its own effective features, it is difficult to obtain high accuracy land cover products derived from a single satellite’s data, perhaps because of cloud cover, suboptimal acquisition schedules, and the restriction of data accessibility. In this study, we integrated Landsat 5, 7, and 8, Sentinel-2, Advanced Land Observing Satellite Advanced Visual, and Near Infrared Radiometer type 2 (ALOS/AVNIR-2), ALOS Phased Array L-band Synthetic Aperture Radar (PALSAR) Mosaic, ALOS-2/PALSAR-2 Mosaic, Shuttle Radar Topography Mission (SRTM), and ancillary data, using kernel density estimation to map and analyze land use/cover change (LUCC) over Central Vietnam from 2007 to 2017. The region was classified into nine categories, i.e., water, urban, rice paddy, upland crops, grassland, orchard, forest, mangrove, and bare land by an automatic model which was trained and tested by 98,000 reference data collected from field surveys and visual interpretations. Results were the 2007 and 2017 classified maps with the same spatial resolutions of 10 m and the overall accuracies of 90.5% and 90.6%, respectively. They indicated that Central Vietnam experienced an extensive change in land cover (33 ± 18% of the total area) during the study period. Gross gains in forests (2680 km2) and water bodies (570 km2) were primarily from conversion of orchards, paddy fields, and crops. Total losses in bare land (495 km2) and paddy (485 km2) were largely to due transformation to croplands and urban & other infrastructure lands. In addition, the results demonstrated that using global land cover products for specific applications is impaired because of uncertainties and inconsistencies. These findings are essential for the development of resource management strategy and environmental studies.
    Electronic ISSN: 2072-4292
    Topics: Architecture, Civil Engineering, Surveying , Geography
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  • 33
    Publication Date: 2018-09-05
    Description: Remote Sensing, Vol. 10, Pages 1405: Investigations on the Coregistration of Sentinel-1 TOPS with the Conventional Cross-Correlation Technique Remote Sensing doi: 10.3390/rs10091405 Authors: Yuxiao Qin Daniele Perissin Jing Bai In Sentinel-1 TOPS mode, the antenna sweeps in the azimuth direction for the purpose of illuminating the targets with the entire azimuth antenna pattern (AAP). This azimuth sweeping introduces an extra high-frequency Doppler term into the impulse response function (IRF), which poses a more strict coregistration accuracy for the interferometric purpose. A 1/1000 pixel coregistration accuracy is required for the interferometric phase error to be negligible, and the enhanced spectral diversity (ESD) method is applied for achieving such accuracy. However, since ESD derives miscoregistration from cross-interferometric phase, and phase is always wrapped to [ − π , π ) , an initial coregistration method with enough accuracy is required to resolve the phase ambiguity in ESD. The mainstream for initial coregistration that meets this requirement is the geometrical approach, which accuracy mainly depends on the accuracy of orbits. In this article, the authors propose to investigate the feasibility of using the conventional coregistration approach, namely the cross-correlation-and-rigid-transformation, as the initial coregistration method. The aim is to quantify the coregistration accuracy for cross-correlation-and-rigid-transformation using the Cramér-Rao lower bound (CRLB) and determine whether this method could eventually help to resolve the phase ambiguities of ESD. In addition, we studied the feasibility and robustness of the cross-correlation plus ESD under different conditions. For validation, we checked whether the cross-correlation plus ESD approach could reach the same coregistration accuracy as geometrical plus ESD approach. In general, for large areas with enough coherence and little topography variance, the cross-correlation method could be used as an alternative to the geometrical approach. The interferogram from the two different approaches (with ESD applied afterward) shows a negligible difference under such circumstances.
    Electronic ISSN: 2072-4292
    Topics: Architecture, Civil Engineering, Surveying , Geography
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  • 34
    Publication Date: 2018-08-14
    Description: Remote Sensing, Vol. 10, Pages 1275: Focusing High-Resolution Airborne SAR with Topography Variations Using an Extended BPA Based on a Time/Frequency Rotation Principle Remote Sensing doi: 10.3390/rs10081275 Authors: Chunhui Lin Shiyang Tang Linrang Zhang Ping Guo With the increasing requirement for resolution, the negligence of topography variations causes serious phase errors, which leads to the degradation of the focusing quality of the synthetic aperture (SAR) imagery, and geometric distortion. Hence, a precise and fast algorithm is necessary for high-resolution airborne SAR. In this paper, an extended back-projection (EBP) algorithm is proposed to compensate the phase errors caused by topography variations. Three-dimensional (3D) variation will be processed in the time-domain for high-resolution airborne SAR. Firstly, the quadratic phase error (QPE) brought by topography variations is analyzed in detail for high-resolution airborne SAR. Then, the key operation, a time-frequency rotation operation, is applied to decrease the samplings in the azimuth time-domain. Just like the time-frequency rotation of the conventional two-step approach, this key operation can compress data in an azimuth time-domain and it reduces the computational burden of the conventional back-projection algorithm, which is applied lastly in the time-domain processing. The results of the simulations validate that the proposed algorithm, including frequency-domain processing and time-domain processing can obtain good focusing performance. At the same time, it has strong practicability with a small amount of computation, compared with the conventional algorithm.
    Electronic ISSN: 2072-4292
    Topics: Architecture, Civil Engineering, Surveying , Geography
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  • 35
    Publication Date: 2018-08-14
    Description: Remote Sensing, Vol. 10, Pages 1272: Mapping Damage-Affected Areas after Natural Hazard Events Using Sentinel-1 Coherence Time Series Remote Sensing doi: 10.3390/rs10081272 Authors: Stephanie Olen Bodo Bookhagen The emergence of the Sentinel-1A and 1B satellites now offers freely available and widely accessible Synthetic Aperture Radar (SAR) data. Near-global coverage and rapid repeat time (6–12 days) gives Sentinel-1 data the potential to be widely used for monitoring the Earth’s surface. Subtle land-cover and land surface changes can affect the phase and amplitude of the C-band SAR signal, and thus the coherence between two images collected before and after such changes. Analysis of SAR coherence therefore serves as a rapidly deployable and powerful tool to track both seasonal changes and rapid surface disturbances following natural disasters. An advantage of using Sentinel-1 C-band radar data is the ability to easily construct time series of coherence for a region of interest at low cost. In this paper, we propose a new method for Potentially Affected Area (PAA) detection following a natural hazard event. Based on the coherence time series, the proposed method (1) determines the natural variability of coherence within each pixel in the region of interest, accounting for factors such as seasonality and the inherent noise of variable surfaces; and (2) compares pixel-by-pixel syn-event coherence to temporal coherence distributions to determine where statistically significant coherence loss has occurred. The user can determine to what degree the syn-event coherence value (e.g., 1st, 5th percentile of pre-event distribution) constitutes a PAA, and integrate pertinent regional data, such as population density, to rank and prioritise PAAs. We apply the method to two case studies, Sarpol-e, Iran following the 2017 Iran-Iraq earthquake, and a landslide-prone region of NW Argentina, to demonstrate how rapid identification and interpretation of potentially affected areas can be performed shortly following a natural hazard event.
    Electronic ISSN: 2072-4292
    Topics: Architecture, Civil Engineering, Surveying , Geography
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  • 36
    Publication Date: 2018-09-05
    Description: Sensors, Vol. 18, Pages 2945: A Residual Analysis-Based Improved Particle Filter in Mobile Localization for Wireless Sensor Networks Sensors doi: 10.3390/s18092945 Authors: Long Cheng Liang Feng Yan Wang Wireless sensor networks (WSNs) have become a popular research subject in recent years. With the data collected by sensors, the information of a monitored area can be easily obtained. As a main contribution of WSN localization is widely applied in many fields. However, when the propagation of signals is obstructed there will be some severe errors which are called Non-Line-of-Sight (NLOS) errors. To overcome this difficulty, we present a residual analysis-based improved particle filter (RAPF) algorithm. Because the particle filter (PF) is a powerful localization algorithm, the proposed algorithm adopts PF as its main body. The idea of residual analysis is also used in the proposed algorithm for its reliability. To test the performance of the proposed algorithm, a simulation is conducted under several conditions. The simulation results show the superiority of the proposed algorithm compared with the Kalman Filter (KF) and PF. In addition, an experiment is designed to verify the effectiveness of the proposed algorithm in an indoors environment. The localization result of the experiment also confirms the fact that the proposed algorithm can achieve a lower localization error compared with KF and PF.
    Electronic ISSN: 1424-8220
    Topics: Chemistry and Pharmacology , Electrical Engineering, Measurement and Control Technology
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  • 37
    Publication Date: 2018-09-05
    Description: Sensors, Vol. 18, Pages 2947: A Dynamic Calibration Method of Installation Misalignment Angles between Two Inertial Navigation Systems Sensors doi: 10.3390/s18092947 Authors: Ming Hua Kui Li Yanhong Lv Qi Wu Generally, in order to ensure the reliability of Navigation system, vehicles are usually equipped with two or more sets of inertial navigation systems (INSs). Fusion of navigation measurement information from different sets of INSs can improve the accuracy of autonomous navigation effectively. However, due to the existence of misalignment angles, the coordinate axes of different systems are usually not in coincidence with each other absolutely, which would lead to serious problems when integrating the attitudes information. Therefore, it is necessary to precisely calibrate and compensate the misalignment angles between different systems. In this paper, a dynamic calibration method of misalignment angles between two systems was proposed. This method uses the speed and attitude information of two sets of INSs during the movement of the vehicle as measurements to dynamically calibrate the misalignment angles of two systems without additional information sources or other external measuring equipment, such as turntable. A mathematical model of misalignment angles between two INSs was established. The simulation experiment and the INSs vehicle experiments were conducted to verify the effectiveness of the method. The results show that the calibration accuracy of misalignment angles between the two sets of systems can reach to 1″ while using the proposed method.
    Electronic ISSN: 1424-8220
    Topics: Chemistry and Pharmacology , Electrical Engineering, Measurement and Control Technology
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  • 38
    Publication Date: 2018-09-05
    Description: Sensors, Vol. 18, Pages 2935: Microfluidically Frequency-Reconfigurable Quasi-Yagi Dipole Antenna Sensors doi: 10.3390/s18092935 Authors: Syed Imran Hussain Shah Sungjoon Lim In this paper, a frequency reconfigurable quasi-Yagi dipole antenna is proposed by leveraging the properties of microfluidic technology. The proposed antenna comprises a metal-printed driven dipole element and three directors. To tune resonant frequencies, microfluidic channels are integrated into the driven element. To maintain a high gain for all the tuned frequencies, microfluidic channels are also integrated into the directors. Therefore, the length of the driven-element as well as directors can be controlled by injecting liquid metal in the microfluidic channels. The proposed antenna has the capability of tuning the frequency by varying the length of the metal-filled channels, while maintaining a high gain for all the tuned frequencies. The proposed antenna’s performance is experimentally demonstrated after fabrication. The injected amount of liquid metal into the microfluidic channels is controlled using programmable pneumatic micropumps. The prototype exhibits continuous tuning of the resonant frequencies from 1.8 GHz to 2.4 GHz; the measured peak gain of the proposed antenna is varied in the range of 8 dBi to 8.5 dBi. Therefore, continuous tuning with high gain is successfully demonstrated using liquid-metal-filled microfluidic channels.
    Electronic ISSN: 1424-8220
    Topics: Chemistry and Pharmacology , Electrical Engineering, Measurement and Control Technology
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  • 39
    Publication Date: 2018-09-05
    Description: Sensors, Vol. 18, Pages 2934: Electrocomposite Developed with Chitosan and Ionic Liquids Using Screen-Printed Carbon Electrodes Useful to Detect Rutin in Tropical Fruits Sensors doi: 10.3390/s18092934 Authors: Lili Muñoz Verónica Arancibia Olimpo García-Beltrán Edgar Nagles John J. Hurtado This work reports the development of a composite of the ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM]BP4) and chitosan (CS) described in previous reports through a new method using cyclic voltammetry with 10 cycles at a scan rate of 50.0 mV s−1. This method is different from usual methods such as casting, deposition, and constant potential, and it allows the development of an electroactive surface toward the oxidation of rutin by stripping voltammetry applied to the detection in tropical fruits such as orange, lemon, and agraz (Vaccinium meridionale Swartz), with results similar to those reported in previous studies. In addition, the surface was characterized by electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM), and Raman spectroscopy. The limit of detection was 0.07 µmol L−1 and the relative standard deviation (RSD) of 10 measurements using the same modified electrode was 0.86%. Moreover, the stability of the sensor was studied for six days using the same modified electrode, where the variation of the signal using a known concentration of rutin (RT) was found to be less than 5.0%. The method was validated using a urine chemistry control spiked with known amounts of RT and possible interference was studied using ten substances including organic and biological compounds, metal ions, and dyes. The results obtained in this study demonstrated that this electrodeveloped composite was sensitive, selective, and stable.
    Electronic ISSN: 1424-8220
    Topics: Chemistry and Pharmacology , Electrical Engineering, Measurement and Control Technology
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  • 40
    Publication Date: 2018-09-05
    Description: Sensors, Vol. 18, Pages 2944: Dynamic Toolface Estimation for Rotary Steerable Drilling System Sensors doi: 10.3390/s18092944 Authors: Weiliang Wang Yanfeng Geng Kai Wang Jieru Si Joice de Oliveira Fiaux In drilling engineering, Toolface is an angle used to describe bit direction. It is a challenging task to accurately estimate Toolface while drilling because of the downhole harsh conditions, but it is a primary step for the dynamic point-the-bit rotary steerable system (DPRSS). A new dynamic Toolface estimator is present, which fuses measurements from two accelerometers and one gyro. A dual-accelerometer Toolface measuring method is designed to compensate the circumferential acceleration of DPRSS. A nonlinear Complementary Filter (CF) is used to suppress the effect of vibration and axial acceleration. The frequency-domain characteristics of nonlinear CF are analyzed and its natural frequency is determined adaptively based on real time drilling conditions. This new estimator is validated on a DPRSS prototype under typical drilling modes; it is demonstrated with high robustness and follows the references satisfactorily.
    Electronic ISSN: 1424-8220
    Topics: Chemistry and Pharmacology , Electrical Engineering, Measurement and Control Technology
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  • 41
    Publication Date: 2018-09-05
    Description: Sensors, Vol. 18, Pages 2946: Performance Analysis of IoT-Based Sensor, Big Data Processing, and Machine Learning Model for Real-Time Monitoring System in Automotive Manufacturing Sensors doi: 10.3390/s18092946 Authors: Muhammad Syafrudin Ganjar Alfian Norma Latif Fitriyani Jongtae Rhee With the increase in the amount of data captured during the manufacturing process, monitoring systems are becoming important factors in decision making for management. Current technologies such as Internet of Things (IoT)-based sensors can be considered a solution to provide efficient monitoring of the manufacturing process. In this study, a real-time monitoring system that utilizes IoT-based sensors, big data processing, and a hybrid prediction model is proposed. Firstly, an IoT-based sensor that collects temperature, humidity, accelerometer, and gyroscope data was developed. The characteristics of IoT-generated sensor data from the manufacturing process are: real-time, large amounts, and unstructured type. The proposed big data processing platform utilizes Apache Kafka as a message queue, Apache Storm as a real-time processing engine and MongoDB to store the sensor data from the manufacturing process. Secondly, for the proposed hybrid prediction model, Density-Based Spatial Clustering of Applications with Noise (DBSCAN)-based outlier detection and Random Forest classification were used to remove outlier sensor data and provide fault detection during the manufacturing process, respectively. The proposed model was evaluated and tested at an automotive manufacturing assembly line in Korea. The results showed that IoT-based sensors and the proposed big data processing system are sufficiently efficient to monitor the manufacturing process. Furthermore, the proposed hybrid prediction model has better fault prediction accuracy than other models given the sensor data as input. The proposed system is expected to support management by improving decision-making and will help prevent unexpected losses caused by faults during the manufacturing process.
    Electronic ISSN: 1424-8220
    Topics: Chemistry and Pharmacology , Electrical Engineering, Measurement and Control Technology
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  • 42
    Publication Date: 2018-09-05
    Description: Sustainability, Vol. 10, Pages 3166: New Market Opportunities and Consumer Heterogeneity in the U.S. Organic Food Market Sustainability doi: 10.3390/su10093166 Authors: GwanSeon Kim Jun Ho Seok Tyler B. Mark This paper investigates what factors and characteristics of organic consumers affect annual organic food expenditure by using Nielsen’s consumer panel dataset from 2010 to 2014. To be specific, this paper explores new marketing opportunities by investigating organic consumer heterogeneity in different household income levels by utilizing the multilevel model. Findings in this study will contribute to the previous and existing literature in three-folds. First, we find that the organic consumers are more heterogeneous in the high-level of income groups (approximately above $60,000), as well as the low-income households between $35,000 and $45,000. This finding demonstrates that the income levels above $60,000 and around $40,000 have potential market segmentation. Second, we find that that annual organic expenditure is positively associated with consumers who consecutively repurchase organic food products compared to irregular organic consumers, supporting a different level of satisfaction. Third, we find that USDA organic labeling has a positive effect on annual organic expenditure compared to the organic labeling certified by private companies, implying the importance of credibility for the organic labeling.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 43
    Publication Date: 2018-09-05
    Description: Sustainability, Vol. 10, Pages 3167: Designing a Sustainable Development Goal Index through a Goal Programming Model: The Case of EU-28 Countries Sustainability doi: 10.3390/su10093167 Authors: Francisco Guijarro Juan A. Poyatos The 17 Sustainable Development Goals (SDGs) adopted by the United Nations are at the center of the global political agenda to eradicate extreme poverty, achieve universal education, promote gender equality and ensure environmental sustainability between others. These goals are organised in 169 indicators, which give an accurate perspective on the main dimensions related with country sustainable development. To gain insight into the relative position of involved countries, it is necessary to develop a composite index that summarises the global progress in the achievement of these goals, but considering possible conflicts and trade-offs between individual SDGs. The objective of this paper is to introduce a Goal Programming model to calculate a composite SDG index, capable of overcoming some of the limitations of celebrated approaches such as arithmetic and geometric averages. The proposed model balances between two extreme solutions: one which calculates a consensus index that reflects the majority trend of the SDGs, and another one which biases the estimated index towards those SDGs that show the most discrepancy with the rest. The model is applied on the EU-28 countries, and shows that the best performing countries regarding the sustainable development are Austria and Luxembourg, while Greece and Romania remain as the worst performers.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 44
    Publication Date: 2018-09-05
    Description: Sustainability, Vol. 10, Pages 3164: Do CSR Activities Increase Firm Value? Evidence from the Korean Market Sustainability doi: 10.3390/su10093164 Authors: Chune Young Chung Sangjun Jung Jason Young Corporate social responsibility has recently become a new metric of corporate performance. Some argue that corporate social responsibility should be used not only for corporate image improvement, but also as a major competitive strategy. Given this perspective, this study considers the effect of corporate social responsibility on firm value using data from all firms listed on the Korea Exchange from 2005 to 2015 that provide corporate social responsibility information. Specifically, we use the Korea Economic Justice Institution Index, which is an important metric for corporate social responsibility in Korea, to empirically analyze the relation between corporate social responsibility and firm value. Further, given the growing attention to the Korean manufacturing environment and the significant influence of the global manufacturing environment, we aim to determine the differential characteristics of manufacturing corporations using the relation between corporate social responsibility and firm value. The results strongly support a positive relation between corporate social responsibility and firm value. Furthermore, our detailed analysis of the manufacturing industry indicates some differential characteristics with respect to this relation. Overall, we find that every corporation should adopt corporate social responsibility as an active competitive strategy, taking the corporate condition into account.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 45
    Publication Date: 2018-09-05
    Description: Sustainability, Vol. 10, Pages 3160: An Assessment of the Implementation of the European Tourism Indicator System for Sustainable Destinations in Italy Sustainability doi: 10.3390/su10093160 Authors: Patrizia Modica Alessandro Capocchi Ilaria Foroni Mariangela Zenga The European Tourism Indicators System (ETIS) is a product of the European Union (EU) Sustainable Development Strategy, which was formulated with the objectives of promoting economic prosperity, social equity, cohesion, and environmental protection. In this paper, we present an analysis of the results of the implementation of the ETIS during the period 2013–2016, in the Italian tourist destination of South Sardinia. While the implementation of ETIS constitutes a significant advancement in Italy, and more widely in Europe, our findings reveal that an adaptive management approach is necessary for achieving the anticipated objectives and adapting these standardized indicators to different territorial contexts. Difficulties were encountered in both data collection and stakeholders’ involvement in the implementation process. Insufficient knowledge, and familiarity with the complex technical aspects of the indicator toolkit among primary stakeholders, was another constraint associated with its implementation. We believe that the findings of this analysis can provide guidelines and inputs for other European countries and tourist destinations that are currently in the process of implementing the ETIS toolkit or similar methodologies. In particular, the pioneering sustainable tourism performance measurement system (STPMS) can be adapted to meet local needs.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 46
    Publication Date: 2018-09-05
    Description: Sensors, Vol. 18, Pages 2933: Membrane-Based Microwave-Mediated Electrochemical Immunoassay for the In Vitro, Highly Sensitive Detection of Osteoporosis-Related Biomarkers Sensors doi: 10.3390/s18092933 Authors: Hye Youn Kim Shinobu Sato Shigeori Takenaka Min-Ho Lee Highly sensitive and multiplexed in vitro detection of osteoporosis-related biochemical markers were carried out based on the membrane-based microwave-mediated electrochemical immunoassay (MMeEIA), where we can dramatically reduce the sample preparation time by shortening the incubation time of conjugation to obtain sensitive detection based on three dimensional conjugation of antibodies with target antigens in nylon membrane disk. C-terminal cross-linked telopeptide of type I collagen (CTx), Osteocalcin (OC), parathyroid hormone (PTH), and N-terminal propeptide of type I collagen (P1NP), which can be utilized to monitor the progress of osteoporosis, were quantified using their corresponding antibody immobilized in membranes. Coefficient of variations in this intra- and inter-assays were within 8.0% for all markers. When compared with data obtained from clinically used standard equipment (Roche modular E170), their coefficients of determination, R2 values, are mostly more than 0.9. They show that the results obtained from MMeEIA are in good agreement with that from the conventional clinical instruments.
    Electronic ISSN: 1424-8220
    Topics: Chemistry and Pharmacology , Electrical Engineering, Measurement and Control Technology
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  • 47
    Publication Date: 2018-09-05
    Description: Sustainability, Vol. 10, Pages 3159: Usability of the EPC Tools for the Profitability Calculation of a Retrofitting in a Residential Building Sustainability doi: 10.3390/su10093159 Authors: Alex Gonzalez Caceres Muriel Diaz After the oil crisis in the 70s energy regulation codes were implemented, but a great portion of existing dwellings have not been retrofitted to current requirements. To face this issue several actions were taken in the European Union (EU), among these, the implementation of Energy Performance Certificates (EPC), which include a Recommendation List of Measures (RLMs) to retrofit buildings. Some concerns exist about the lack of confidence on these recommendations. The main objective of this study is to analyze the usefulness of the EPC, answering if it is possible to deliver a realistic financial assessment about renovation strategies using these tools. The study is based on three indicators: Consumption, energy saving variations and profitability. The study is based on a renovation project case study, where simulations and Life Cycle Cost Assessment (LCCA) were performed, in order to identify the different results that EPC’s and an energy efficiency assessment could lead to. The results show important differences in all the concepts evaluated.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 48
    Publication Date: 2018-09-05
    Description: Sustainability, Vol. 10, Pages 3165: Frame Analysis of ENGO Conceptualization of Sustainable Forest Management: Environmental Justice and Neoliberalism at the Core of Sustainability Sustainability doi: 10.3390/su10093165 Authors: Nenad Šimunović Franziska Hesser Tobias Stern Normative judgments on sustainability underpin concepts that shape the supply scenarios of timber consumption. The modern understanding of sustainable forest management is shaped by a diverse spectrum of social demands, going beyond the principle of sustainable yield management. Rival stakeholders compete to incorporate their ideas and interpretations of sustainable forest management into policy institutions. Environmental non-governmental organizations (ENGOs) have emerged as one of the dominant stakeholders in the forest-based sector. We set out to explore ENGO-specific conceptualizations of sustainable forest management and investigate differences in understanding among various ENGOs. By conducting a frame analysis of ENGO press releases, we identified two master frames: environmental justice and environmentalist frames. A difference in the emphasis placed on procedural and distributive justice as well as a different standpoint in the commons versus commodity debate emerged as the main divergences between the master frames. The results of our study demonstrate how the differences between the master frames underpin different conceptualizations of sustainable forest management. On the one hand, the ENGOs associated with the environmental justice master frame advocate for the broader implementation of community forest management based on power-sharing. On the other hand, the ENGOs associated with the environmentalist master frame promote a wide range of approaches associated with ecosystem management and social forestry paradigms. Moreover, the ENGOs associated with the environmentalist master frame challenge the concept of sustainable forest management as defined by the Helsinki and Montreal process by advocating for ecosystem management. The ENGOs associated with the environmental justice master frame reject the mainstream concept of sustainable forest management in any guise. Future research on ethical issues underlying forestry concepts may provide more conceptual and operational clarity for both forest managers and policy-makers.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 49
    Publication Date: 2018-09-05
    Description: Sustainability, Vol. 10, Pages 3158: Critical Behavioral Risk Factors among Principal Participants in the Chinese Construction Industry Sustainability doi: 10.3390/su10093158 Authors: Pengcheng Xiang Fuyuan Jia Xiaohui Li The main participants in construction projects are the client, contractors, material suppliers, and consultants such as the project supervisor. They play the most important roles in implementing construction projects, and their behavior has a significant impact on the project’s performance. Because each participant has their own particular interests, by virtue of proprietary information advantage, each individual participant is driven to achieve maximum benefit, which can result in improper behavior with respect to each other. The risk of this resulting in moral hazard and adverse selection based on information asymmetry is called behavioral risk among principal construction participants. Behavior is affected by various risk factors; successful implementation of construction projects depends on effective management of the key risk factors. This paper identifies and ranks the critical behavioral risk factors from the perspective of principal construction participants in the Chinese construction industry. The data used for analysis is based on an interview and questionnaire survey. Factor analysis is conducted with the assistance of SPSS17.0. Forty-one potential behavioral risk factors are identified, with 30 of those being critical, including “client changes project objective or investment direction”, “designer uses technological capability advantage to obtain profit”, and others. These findings contribute to the understanding of risk management in the construction industry in China. They also serve as a useful reference for further studies on the subject.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 50
    Publication Date: 2018-09-05
    Description: Sustainability, Vol. 10, Pages 3149: Innovative Blockchain-Based Approach for Sustainable and Credible Environment in Food Trade: A Case Study in Shandong Province, China Sustainability doi: 10.3390/su10093149 Authors: Dianhui Mao Zhihao Hao Fan Wang Haisheng Li Agri-food trade has a profound impact on social stability and sustainable economic development. However, there are several technological problems in current agricultural product transactions. For example, it is almost impossible to improve the efficiency of transactions and maintain market stability. This paper designs a novel Food Trading System with COnsortium blockchaiN (FTSCON) to eliminate information asymmetry in the food trade, in order to establish a sustainable and credible trading environment, the system uses consortium blockchain technology to meet the challenge of different authentications and permissions for different roles in food trade. Meanwhile, we have used the online double auction mechanism to eliminate competition. We also have designed a improved Practical Byzantine Fault Tolerance (iPBFT) algorithm to improve efficiency. In addition, a case study based on a series of data from Shandong Province, China indicate that the FTSCON can achieve profit improvement of merchants. Therefore, the proposed system proved to have high commercial value.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 51
    Publication Date: 2018-09-05
    Description: Symmetry, Vol. 10, Pages 380: The Weighted Arithmetic Mean–Geometric Mean Inequality is Equivalent to the Hölder Inequality Symmetry doi: 10.3390/sym10090380 Authors: Yongtao Li Xian-Ming Gu Jianxing Zhao In the current note, we investigate the mathematical relations among the weighted arithmetic mean–geometric mean (AM–GM) inequality, the Hölder inequality and the weighted power-mean inequality. Meanwhile, the proofs of mathematical equivalence among the weighted AM–GM inequality, the weighted power-mean inequality and the Hölder inequality are fully achieved. The new results are more generalized than those of previous studies.
    Electronic ISSN: 2073-8994
    Topics: Mathematics , Physics
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  • 52
    Publication Date: 2018-09-05
    Description: Sustainability, Vol. 10, Pages 3154: Design Methodology for Street-Oriented Block Housing Considering Daylight and Natural Ventilation Sustainability doi: 10.3390/su10093154 Authors: Ho-Jeong Kim Jin-Soo Kim This study presents a design methodology for street-oriented block housing, as a model for gradual small-scale block-unit development, that can secure two hours of continuous access to daylight on the winter solstice at azimuth angles of 0° and 60° in Seoul, South Korea, and, in addition, developed a methodology for wind path planning for existing types of developed housing. The results of this study have confirmed the feasibility of a housing design that can secure two hours of continuous access to daylight along with no less than 200 percent of development density, achieved through the elimination of self-shadows by using distances between residential buildings and shadow characteristics according to azimuth angles. In addition, the study identified an air flow stagnation section by assessing the air flow of the exterior space of street-oriented block housing in consideration of day-lit environments, and examined a planning model that can enhance natural ventilation potential by activating the air flow of the exterior space. Wind path planning was conducted for 24 alternatives that were produced based on the developed design methodology, and the wind velocity ratio of street-oriented block housing ranged from 0.34 to 0.59. In terms of disadvantages of street-oriented block housing in securing wind paths, this study confirmed that air flow could be strengthened by adjusting the form of the lower-part opening, which is open in the direction of incoming wind, designing a staggered mass layout in high-rise masses, and combining building floor heights. The above findings of this study suggest that a performance-based approach is necessary for the improvement of environmental performance in street-oriented block housing, in consideration of azimuth angles and the prevailing wind direction from the initial phase of planning.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 53
    Publication Date: 2018-09-05
    Description: Sustainability, Vol. 10, Pages 3150: Multi-Criteria Group Decision Making for Green Supply Chain Management under Uncertainty Sustainability doi: 10.3390/su10093150 Authors: Hepu Deng Feng Luo Santoso Wibowo This paper presents a multi-criteria group decision making model for effectively evaluating the performance of green supply chain management (GSCM) practices under uncertainty in an organization. The subjective assessments of individual decision makers are appropriately represented with the use of intuitionistic fuzzy numbers for better tackling the uncertainty existent. An algorithm is developed to assist individual decision makers in evaluating the performance of alternative GSCM practices across all the evaluation criteria. An example is presented for demonstrating the applicability of the proposed model in solving similar problems in the real-world setting.
    Electronic ISSN: 2071-1050
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  • 54
    Publication Date: 2018-09-05
    Description: Sustainability, Vol. 10, Pages 3152: InSAR Monitoring of Italian Coastline Revealing Natural and Anthropogenic Ground Deformation Phenomena and Future Perspectives Sustainability doi: 10.3390/su10093152 Authors: Marco Polcari Matteo Albano Antonio Montuori Christian Bignami Cristiano Tolomei Giuseppe Pezzo Sergio Falcone Carmelo La Piana Fawzi Doumaz Stefano Salvi Salvatore Stramondo In this work, we use X and C-band SAR data provided by the COSMO-SkyMed and ENVISAT missions to detect and measure some ground deformation phenomena along six coastal areas of Italy. In particular, we exploit multi-temporal interferometric synthetic aperture radar (InSAR), i.e., small baseline subsets (SBAS) and interferometric point target analysis (IPTA) methods, to retrieve the deformation rate maps and time series for each investigated area. Multi-temporal InSAR analysis revealed local subsidence and uplifting effects in Ravenna Coastal Areas, Fiumicino, Campi Flegrei, Sibari Plain, Augusta Bay, and Taranto Gulf. Our work is meant as a demonstrator to show how InSAR-based analysis can provide a detailed understanding of the coastal hazards. Such analysis also opens up new monitoring scenarios such as the possibility of designing a near real-time surveillance service based on Sentinel-1 SAR data.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 55
    Publication Date: 2018-09-05
    Description: Sustainability, Vol. 10, Pages 3151: Foreign Monitoring and Audit Quality: Evidence from Korea Sustainability doi: 10.3390/su10093151 Authors: Sang Cheol Lee Mooweon Rhee Jongchul Yoon This study investigates the effects of both foreign majority shareholders and foreign investors’ participation in the board of directors on audit quality, as reflected by auditor size and audit fees. In addition, the study examines the moderating effect of an agency problem on the relationship between foreign investors and the monitoring of audit quality. Using 1574 non-financial firm-year observations listed on the Korea Stock Exchange from 2000 to 2003, we find that the presence of foreign investors such as foreign block shareholders and foreign outside directors increases audit quality. At the same time, the monitoring role of foreign block shareholders is more powerful than that of foreign external directors. Moreover, the foreign block shareholders in professional management-controlled firms exert a more profound influence on audit quality than do those in owner-controlled ones. These test results imply that foreign investors with independence, expertise, and monitoring incentives could play an important role in improving the corporate governance system in Korea, which in turn would not only enhance firm value, but also strengthen the sustainability of Korean companies.
    Electronic ISSN: 2071-1050
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  • 56
    Publication Date: 2018-09-05
    Description: Symmetry, Vol. 10, Pages 381: Time-Dependent Behavior of a Circular Symmetrical Tunnel Supported with Rockbolts Symmetry doi: 10.3390/sym10090381 Authors: Wei Han Gang Wang Chuanzheng Liu Hengjie Luan Ke Wang Under the effect of initial stress and excavation disturbance, there exists interaction between rock mass and rockbolt in deeply buried tunnels. In order to fully explore the mechanism of rock mass supported with rockbolts, this article studied the time-dependent behavior of the rock mass supported with discretely mechanically or frictionally coupled (DMFC) rockbolts. The interaction model elastic solutions under distributed force model were analyzed, then the viscoelastic analytical solutions were conducted to describe the rheological properties of the coupling model, and the solutions were acquired by setting the constitutive models of the rockbolt and rock mass in terms of a one-dimensional Kelvin model and a three-dimensional Burgers model based on material properties and dimension. Several examples were performed and the influence of initial stress σ0, the viscosity parameters η1 and η2 of the three-dimensional Burgers model as well as the pre-tension T0 on reinforcement effect were analyzed. According to the proposed model, the smaller η2 is or the larger the pre-tension T0 is, the more effective the support effect. However, when the pre-tension is too large, the support effect is no longer significantly enhanced. In addition, the early reinforcement effect is controlled by the first creep stage in the Burgers model while the ultimate support effect is mainly influenced by the viscosity coefficient of the second creep stage in the Burgers model. This research can provide an important theoretical reference to guide the parameter design of rockbolt reinforcement engineering in a circular symmetrical tunnel.
    Electronic ISSN: 2073-8994
    Topics: Mathematics , Physics
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  • 57
    Publication Date: 2018-09-05
    Description: Water, Vol. 10, Pages 1189: Optimization of China Sponge City Design: The Case of Lincang Technology Innovation Park Water doi: 10.3390/w10091189 Authors: Nan Li Chengxin Qin Pengfei Du China launched the sponge city (SPC) initiative in 2013 to reduce municipal stormwater runoff. The design criteria are mainly the annual comprehensive runoff coefficient (ACRC) regulated in a design guideline. Numerous SPC alternatives with varied low-impact development (LID) measures can be designed to meet the ACRC. Obviously, the optimization of SPC design is significant. This study provides an approach to SPC design optimization that applies an optimized module of SUSTAIN to simulate SPC performance over a 10-year period. The targeted volume reduction was derived from the SWMM model and corresponded to the ACRC criteria. Based on the reduction, the minimal cost and cost-effectiveness analyses were conducted. The proposed approach was applied to the Lincang Technology Innovation Park (LCTIP) as a test case. Three scenarios were analyzed: The original design implemented on the site, the landscape improved design, and the most economical design. The results indicated that the optimized alternative may save up to 12.3% of the cost while meeting that ACRC value. The approach improves upon SPC design, particularly with regards to flood control. The present research will help decision makers to develop and select the most appropriate SPC design that is most cost-effective.
    Electronic ISSN: 2073-4441
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  • 58
    Publication Date: 2018-09-05
    Description: Water, Vol. 10, Pages 1190: A Copula-Based Bayesian Network for Modeling Compound Flood Hazard from Riverine and Coastal Interactions at the Catchment Scale: An Application to the Houston Ship Channel, Texas Water doi: 10.3390/w10091190 Authors: Anaïs Couasnon Antonia Sebastian Oswaldo Morales-Nápoles Traditional flood hazard analyses often rely on univariate probability distributions; however, in many coastal catchments, flooding is the result of complex hydrodynamic interactions between multiple drivers. For example, synoptic meteorological conditions can produce considerable rainfall-runoff, while also generating wind-driven elevated sea-levels. When these drivers interact in space and time, they can exacerbate flood impacts, a phenomenon known as compound flooding. In this paper, we build a Bayesian Network based on Gaussian copulas to generate the equivalent of 500 years of daily stochastic boundary conditions for a coastal watershed in Southeast Texas. In doing so, we overcome many of the limitations of conventional univariate approaches and are able to probabilistically represent compound floods caused by riverine and coastal interactions. We model the resulting water levels using a one-dimensional (1D) steady-state hydraulic model and find that flood stages in the catchment are strongly affected by backwater effects from tributary inflows and downstream water levels. By comparing our results against a bathtub modeling approach, we show that simplifying the multivariate dependence between flood drivers can lead to an underestimation of flood impacts, highlighting that accounting for multivariate dependence is critical for the accurate representation of flood risk in coastal catchments prone to compound events.
    Electronic ISSN: 2073-4441
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 59
    Publication Date: 2018-09-05
    Description: Water, Vol. 10, Pages 1188: Spatial Pattern Oriented Multicriteria Sensitivity Analysis of a Distributed Hydrologic Model Water doi: 10.3390/w10091188 Authors: Mehmet Cüneyd Demirel Julian Koch Gorka Mendiguren Simon Stisen Hydrologic models are conventionally constrained and evaluated using point measurements of streamflow, which represent an aggregated catchment measure. As a consequence of this single objective focus, model parametrization and model parameter sensitivity typically do not reflect other aspects of catchment behavior. Specifically for distributed models, the spatial pattern aspect is often overlooked. Our paper examines the utility of multiple performance measures in a spatial sensitivity analysis framework to determine the key parameters governing the spatial variability of predicted actual evapotranspiration (AET). The Latin hypercube one-at-a-time (LHS-OAT) sampling strategy with multiple initial parameter sets was applied using the mesoscale hydrologic model (mHM) and a total of 17 model parameters were identified as sensitive. The results indicate different parameter sensitivities for different performance measures focusing on temporal hydrograph dynamics and spatial variability of actual evapotranspiration. While spatial patterns were found to be sensitive to vegetation parameters, streamflow dynamics were sensitive to pedo-transfer function (PTF) parameters. Above all, our results show that behavioral model definitions based only on streamflow metrics in the generalized likelihood uncertainty estimation (GLUE) type methods require reformulation by incorporating spatial patterns into the definition of threshold values to reveal robust hydrologic behavior in the analysis.
    Electronic ISSN: 2073-4441
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 60
    Publication Date: 2018-09-05
    Description: Water, Vol. 10, Pages 1191: Sustainable Water Resources Management: A Bibliometric Overview Water doi: 10.3390/w10091191 Authors: Amador Durán-Sánchez José Álvarez-García María de la Cruz del Río-Rama While global water demand continues increasing, the quantity and quality of water resources is decreasing in many regions. Conflicts over competition in the use of water are likely to increase as societies face social, economic and political challenges, especially aggravated by climate change. In this scenario, sustainable management of water resources is a key priority to meet the growing demand for water and to achieve a safe and environmentally sustainable future supply. The main objective of this article was to show an image of the international scientific production related to “Sustainable Water Resources Management” by using the comparative bibliometric study of the documents indexed in the WoS(Web of Science) and Scopus databases as a tool; and to analyze relevant aspects such as their coverage, correlation, overlap, growth, citation, dispersion or concentration, among others. For this purpose, and by means of an advanced search of terms, a representative set of 160 articles in WoS and 210 in Scopus were selected (with a time limit that limited the results to anything published before 2017, including 2017), which form the ad-hoc basis of the analysis. Their significant increase in both the number of articles and citations received in the last 10 years demonstrates the growing interest of the scientific community in its study. Regarding the analysis of the databases, although WoS and Scopus differ in terms of scope, volume of data and coverage policies, both information systems are complementary and non-exclusive. Despite their similarities, Scopus performs better coverage in the specific area of Sustainable Water Resource Management by collecting a greater number of articles and receiving a greater number of citations.
    Electronic ISSN: 2073-4441
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  • 61
    Publication Date: 2018-09-06
    Description: Energies, Vol. 11, Pages 2345: Methane Desorption Characteristics of Coal at Different Water Injection Pressures Based on Pore Size Distribution Law Energies doi: 10.3390/en11092345 Authors: Dong Zhao Tao Gao Yulin Ma Zengchao Feng Methane desorption characteristics of coal under definite water pressure comprises a complex two-phase flow process. A series of mercury intrusion porosimetry (MIP) and desorption experiments at different water injection pressures are reported in this study. Three lumpy coal samples were used in desorption experiments at three different water injection pressures and at natural desorption for comparison. Samples comprising two ranks of coal were used for MIP measurements including the distribution of porosity and pore sizes. The results of this study enable the establishment of a new model that encompasses a critical theoretical pore size that is most effective for water injection into coalbeds and that can be related to water injection pressure, the length of residual water, and gas adsorption capacity. Data show that the use of different water injection pressures leads to different gas desorption capacities as well as variable time effects and degree of gas desorption. Critical pore size is therefore proposed as a new parameter that can be employed to describe high pressure water effects in the context of gas desorption and can be calculated using pore size and the volume distribution law, as well as via the moisture ratio that remains after experiments and the permanent desorption percentage.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 62
    Publication Date: 2018-09-06
    Description: Energies, Vol. 11, Pages 2344: Improved Fuzzy C-Means Clustering for Transformer Fault Diagnosis Using Dissolved Gas Analysis Data Energies doi: 10.3390/en11092344 Authors: Enwen Li Linong Wang Bin Song Siliang Jian Dissolved gas analysis (DGA) of the oil allows transformer fault diagnosis and status monitoring. Fuzzy c-means (FCM) clustering is an effective pattern recognition method, but exhibits poor clustering accuracy for dissolved gas data and usually fails to subsequently correctly classify transformer faults. The existing feasible approach involves combination of the FCM clustering algorithm with other intelligent algorithms, such as neural networks and support vector machines. This method enables good classification; however, the algorithm complexity is greatly increased. In this paper, the FCM clustering algorithm itself is improved and clustering analysis of DGA data is realized. First, the non-monotonicity of the traditional clustering membership function with respect to the sample distance and its several local extrema are discussed, which mainly explain the poor classification accuracy of DGA data clustering. Then, an exponential form of the membership function is proposed to obtain monotony with respect to distance, thereby improving the dissolved gas data clustering. Likewise, a similarity function to determine the degree of membership is derived. Test results for large datasets show that the improved clustering algorithm can be successfully applied for DGA-data-based transformer fault detection.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 63
    Publication Date: 2018-09-06
    Description: Energies, Vol. 11, Pages 2340: Primary Frequency Controller with Prediction-Based Droop Coefficient for Wind-Storage Systems under Spot Market Rules Energies doi: 10.3390/en11092340 Authors: Shengqi Zhang Yateendra Mishra Bei Yuan Jianfeng Zhao Mohammad Shahidehpour Increasing penetration levels of asynchronous wind turbine generators (WTG) reduce the ability of the power system to maintain adequate frequency responses. WTG with the installation of battery energy storage systems (BESS) as wind-storage systems (WSS), not only reduce the intermittency but also provide a frequency response. Meanwhile, many studies indicate that using the dynamic droop coefficient of WSS in primary frequency control (PFC) based on the prediction values, is an effective way to enable the performance of WSS similar to conventional synchronous generators. This paper proposes a PFC for WSS with a prediction-based droop coefficient (PDC) according to the re-bid process under real-time spot market rules. Specifically, WSS update the values of the reference power and droop coefficient discretely at every bidding interval using near-term wind power and frequency prediction, which enables WSS to be more dispatchable in the view of transmission system operators (TSOs). Also, the accurate prediction method in the proposed PDC-PFC achieves the optimal arrangement of power from WTG and BESS in PFC. Finally, promising simulation results for a hybrid power system show the efficacy of the proposed PDC-PFC for WSS under different operating conditions.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 64
    Publication Date: 2018-09-06
    Description: Energies, Vol. 11, Pages 2346: Environmental Impacts of Solar-Photovoltaic and Solar-Thermal Systems with Life-Cycle Assessment Energies doi: 10.3390/en11092346 Authors: M. Mahmud Nazmul Huda Shahjadi Farjana Candace Lang The demand for clean energy is strong, and the shift from fossil-fuel-based energy to environmentally friendly sources is the next step to eradicating the world’s greenhouse gas (GHG) emissions. Solar energy technology has been touted as one of the most promising sources for low-carbon, non-fossil fuel energy production. However, the true potential of solar-based technologies is established by augmenting efficiency through satisfactory environmental performance in relation to other renewable energy systems. This paper presents an environmental life-cycle assessment (LCA) of a solar-photovoltaic (PV) system and a solar-thermal system. Single crystalline Si solar cells are considered for the solar PV system and an evacuated glass tube collector is considered for the solar thermal system in this analysis. A life-cycle inventory (LCI) is developed considering all inputs and outputs to assess and compare the environmental impacts of both systems for 16 impact indicators. LCA has been performed by the International Reference Life Cycle Data System (ILCD), Impact 2002+, Cumulative Energy Demand (CED), Eco-points 97, Eco-indicator 99 and Intergovernmental Panel on Climate Change (IPCC) methods, using SimaPro software. The outcomes reveal that a solar-thermal framework provides more than four times release to air ( 100 % ) than the solar-PV ( 23 . 26 % ), and the outputs by a solar-PV system to soil ( 27 . 48 % ) and solid waste ( 35 . 15 % ) are about one third that of solar-thermal. The findings also depict that the solar panels are responsible for the most impact in the considered systems. Moreover, uncertainty and sensitivity analysis has also been carried out for both frameworks, which reveal that Li-ion batteries and copper-indium-selenium (CIS)-solar collectors perform better than others for most of the considered impact categories. This study revealed that a superior environmental performance can be achieved by both systems through careful selection of the components, taking into account the toxicity aspects, and by minimizing the impacts related to the solar panel, battery and heat storage.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 65
    Publication Date: 2018-09-06
    Description: Energies, Vol. 11, Pages 2342: Effects of Electric Circulation on the Energy Efficiency of the Power Split e-CVT Hybrid Systems Energies doi: 10.3390/en11092342 Authors: Cheng-Ta Chung Chien-Hsun Wu Yi-Hsuan Hung This paper aims at investigating the fundamental characteristics of energy efficiency for power split electronic-continuously-variable-transmission (e-CVT) hybrid systems under the operation of electric circulation, i.e., circulating part of the engine power through the generator and motor in form of electric energy to improve system efficiency as well as perform the continuously-variable-transmission (CVT) functionality. The relations of kinematics and energy conservation for each power component are constructed and analyzed to classify how the operating points of the engine in term of torque and rotational speed may vary under different degrees of electric circulation indicated by a parameter called ratio of circulating power. Thereby, power split e-CVT hybrid systems can be classified into three types: upward circulation, downward circulation, and neutral circulation. Accordingly, two power split e-CVT hybrid systems, one of input split type and the other of output split type, are selected to be analyzed regarding their operating characteristics and simulated on their performances of energy efficiency. As a result, the former is a type of downward circulation in favor of driving at low speed and high driving load, while the latter is a type of upward circulation with an advantage of driving at high speed and low driving load. Thereby, applying this analysis to investigate the effects of electric circulation on power split e-CVT systems may help the developers implement suitable energy management and control strategy in accordance with their corresponding operating characteristics of energy efficiency.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 66
    Publication Date: 2018-09-06
    Description: Energies, Vol. 11, Pages 2338: Physical Activation of Waste-Derived Materials for Biogas Cleaning Energies doi: 10.3390/en11092338 Authors: Davide Papurello Massimo Santarelli Sonia Fiorilli Biogas produced from biomass is carbon neutral. In fact, the carbon feedstock of biomass is converted into gas phase. Biogas use in high efficient energy systems, such as Solid Oxide Fuel Cells is a viable choice. One of the most important drawbacks for such systems is related to the interaction between trace compounds and anode section. Gas cleaning through physical removal mechanisms is the simplest and cheapest method adopted in the literature. Coupled with this solution, the recovery of waste materials is an efficient application of the circular economy approach. In this work, a physical activation process was investigated experimentally for waste-derived materials at a temperature of 700 °C. The removal of H2S was considered as the most abundant trace compound. Activated biochar showed an adsorption capacity comparable to commercial sorbents, while the performance of ashes are still too poor. An important parameter to be considered is the biogas humidity content that enters in competition with trace compounds that must be removed.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 67
    Publication Date: 2018-09-06
    Description: Energies, Vol. 11, Pages 2343: Visualization Investigation of the Influence of Chamber Profile and Injection Parameters on Fuel Spray Spreading in a Double-Layer Diverging Combustion Chamber for a DI Diesel Engine Energies doi: 10.3390/en11092343 Authors: Yao Fu Liyan Feng Hua Tian Wuqiang Long Dongsheng Dong Xianyin Leng The double-layer diverging combustion chamber (DLDC chamber) aims to improve the fuel–air mixing formation and promote in-cylinder air utilization by changing fuel spray spreading characteristics. In order to investigate how the DLDC chamber profile and injection parameters affect the fuel spray spreading, visualization of fuel injection and impingement tests were carried out on two different DLDC chambers with different fuel injection parameters. The visualization test results showed that double-layer fuel spray spreading was obtained in the two DLDC chambers and the peripheral top clearance of each chamber was utilized efficiently. The DLDC chamber with a 50% upper layer volume provided a larger fuel spray distribution region after the start of injection. The DLDC chamber with a 70% upper layer volume obtained a larger fuel spray distribution region with better top clearance utilization at the later stage of injection. The injection parameters mentioned in this research showed significant effects on the fuel spray spreading in the DLDC chamber. Increasing the injection pressure provided a larger fuel spray distribution area at the beginning of injection. Decreasing the nozzle hole diameter had a positive influence on obtaining a larger fuel spray distribution. Advancing the injection timing enabled the enlarging of the fuel distribution region.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 68
    Publication Date: 2018-09-06
    Description: Energies, Vol. 11, Pages 2339: Dynamic Simulations of Adaptive Design Approaches to Control the Speed of an Induction Machine Considering Parameter Uncertainties and External Perturbations Energies doi: 10.3390/en11092339 Authors: Kamran Zeb Waqar U. Din Muhammad Adil Khan Ayesha Khan Umair Younas Tiago Davi Curi Busarello Hee Je Kim Recently, the Indirect Field Oriented Control (IFOC) scheme for Induction Motors (IM) has gained wide acceptance in high performance applications. The IFOC has remarkable characteristics of decoupling torque and flux along with an easy hardware implementation. However, the detuning limits the performance of drives due to uncertainties of parameters. Conventionally, the use of a Proportional Integral Differential (PID) controller has been very frequent in variable speed drive applications. However, it does not allow for the operation of an IM in a wide range of speeds. In order to tackle these problems, optimal, robust, and adaptive control algorithms are mostly in use. The work presented in this paper is based on new optimal, robust, and adaptive control strategies, including an Adaptive Proportional Integral (PI) controller, sliding mode control, Fuzzy Logic (FL) control based on Steepest Descent (SD), Levenberg-Marquardt (LM) algorithms, and Hybrid Control (HC) or adaptive sliding mode controller to overcome the deficiency of conventional control strategies. The main theme is to design a robust control scheme having faster dynamic response, reliable operation for parameter uncertainties and speed variation, and maximized torque and efficiency of the IM. The test bench of the IM control has three main parts: IM model, Inverter Model, and control structure. The IM is modelled in synchronous frame using d q modelling while the Space Vector Pulse Width Modulation (SVPWM) technique is used for modulation of the inverter. Our proposed controllers are critically analyzed and compared with the PI controller considering different conditions: parameter uncertainties, speed variation, load disturbances, and under electrical faults. In addition, the results validate the effectiveness of the designed controllers and are then related to former works.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 69
    Publication Date: 2018-09-06
    Description: Energies, Vol. 11, Pages 2337: Economic Advantages of Dry-Etched Black Silicon in Passivated Emitter Rear Cell (PERC) Photovoltaic Manufacturing Energies doi: 10.3390/en11092337 Authors: Chiara Modanese Hannu S. Laine Toni P. Pasanen Hele Savin Joshua M. Pearce Industrial Czochralski silicon (Cz-Si) photovoltaic (PV) efficiencies have routinely reached >20% with the passivated emitter rear cell (PERC) design. Nanostructuring silicon (black-Si) by dry-etching decreases surface reflectance, allows diamond saw wafering, enhances metal gettering, and may prevent power conversion efficiency degradation under light exposure. Black-Si allows a potential for >20% PERC cells using cheaper multicrystalline silicon (mc-Si) materials, although dry-etching is widely considered too expensive for industrial application. This study analyzes this economic potential by comparing costs of standard texturized Cz-Si and black mc-Si PERC cells. Manufacturing sequences are divided into steps, and costs per unit power are individually calculated for all different steps. Baseline costs for each step are calculated and a sensitivity analysis run for a theoretical 1 GW/year manufacturing plant, combining data from literature and industry. The results show an increase in the overall cell processing costs between 15.8% and 25.1% due to the combination of black-Si etching and passivation by double-sided atomic layer deposition. Despite this increase, the cost per unit power of the overall PERC cell drops by 10.8%. This is a significant cost saving and thus energy policies are reviewed to overcome challenges to accelerating deployment of black mc-Si PERC across the PV industry.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 70
    Publication Date: 2018-09-06
    Description: Energies, Vol. 11, Pages 2341: Influence of NaCl Concentration on Food-Waste Biochar Structure and Templating Effects Energies doi: 10.3390/en11092341 Authors: Ye-Eun Lee Jun-Ho Jo I-Tae Kim Yeong-Seok Yoo Food-waste-derived biochar structures obtained through pyrolysis and with different NaCl concentrations were investigated. Increased NaCl concentration in the samples inhibited cellulose and lignin decomposition, ultimately increasing the biochar yield by 2.7% for 20%-NaCl concentration. NaCl added in solution state exhibited templating effects, with maximum increases in the Brunauer–Emmett–Teller (BET) surface area and pore volume of 1.23 to 3.50 m2∙g−1 and 0.002 to 0.007 cm3∙g−1, respectively, after washing. Adding a high concentration (20%) of NaCl reduced the BET surface area. In contrast, the mean pore diameter increased owing to the increased NaCl clustering area. Increased NaCl clustering with increased added NaCl was shown to have positive effects on NaCl removal by washing. Furthermore, as the NaCl adhered to the KCl scattered in the food waste, a high NaCl concentration also had positive effects on KCl removal. This study reports on an investigation on the effects of varying NaCl concentrations injected in solution form on the structure of food-waste biochar during pyrolysis. The templating effect was considered using both added NaCl and NaCl already contained in the food waste, with implementation of a desalination process essential for food-waste treatment for recycling.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 71
    Publication Date: 2018-09-06
    Description: Entropy, Vol. 20, Pages 675: Optimal Channel Design: A Game Theoretical Analysis Entropy doi: 10.3390/e20090675 Authors: MHR. Khouzani Pasquale Malacaria This paper studies the problem of optimal channel design. For a given input probability distribution and for hard and soft design constraints, the aim here is to design a (probabilistic) channel whose output leaks minimally from its input. To analyse this problem, general notions of entropy and information leakage are introduced. It can be shown that, for all notions of leakage here defined, the optimal channel design problem can be solved using convex programming with zero duality gap. Subsequently, the optimal channel design problem is studied in a game-theoretical framework: games allow for analysis of optimal strategies of both the defender and the adversary. It is shown that all channel design problems can be studied in this game-theoretical framework, and that the defender’s Bayes–Nash equilibrium strategies are equivalent to the solutions of the convex programming problem. Moreover, the adversary’s equilibrium strategies correspond to a robust inference problem.
    Electronic ISSN: 1099-4300
    Topics: Chemistry and Pharmacology , Physics
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  • 72
    Publication Date: 2018-09-06
    Description: Entropy, Vol. 20, Pages 673: Molecules and the Eigenstate Thermalization Hypothesis Entropy doi: 10.3390/e20090673 Authors: David M. Leitner We review a theory that predicts the onset of thermalization in a quantum mechanical coupled non-linear oscillator system, which models the vibrational degrees of freedom of a molecule. A system of N non-linear oscillators perturbed by cubic anharmonic interactions exhibits a many-body localization (MBL) transition in the vibrational state space (VSS) of the molecule. This transition can occur at rather high energy in a sizable molecule because the density of states coupled by cubic anharmonic terms scales as N3, in marked contrast to the total density of states, which scales as exp(aN), where a is a constant. The emergence of a MBL transition in the VSS is seen by analysis of a random matrix ensemble that captures the locality of coupling in the VSS, referred to as local random matrix theory (LRMT). Upon introducing higher order anharmonicity, the location of the MBL transition of even a sizable molecule, such as an organic molecule with tens of atoms, still lies at an energy that may exceed the energy to surmount a barrier to reaction, such as a barrier to conformational change. Illustrative calculations are provided, and some recent work on the influence of thermalization on thermal conduction in molecular junctions is also discussed.
    Electronic ISSN: 1099-4300
    Topics: Chemistry and Pharmacology , Physics
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  • 73
    Publication Date: 2018-09-06
    Description: Energies, Vol. 11, Pages 2326: Dynamic Placement Analysis of Wind Power Generation Units in Distribution Power Systems Energies doi: 10.3390/en11092326 Authors: Mohammad Reza Baghayipour Amin Hajizadeh Amir Shahirinia Zhe Chen The placement problem of distributed generators (DGs) in distribution networks becomes much more complicated in the case of using the DGs with renewable energy resources. Due to several reasons such as, their intermittent output powers, the interactions between DGs and the rest of the distribution network, and considering other involved uncertainties are very vital. This paper develops a new approach for optimal placement of wind energy based DGs (WDGs) in which all of such influences are carefully handled. The proposed method considers the time variations of dynamic nodal demands, nodal voltage magnitudes, and wind speed in the WDG placement process simultaneously. Thereby, an accurate dynamic model of the active and reactive powers injected by the WDG to the system is employed in which the interactions between the WDG and the distribution network are well regarded. Finally, simulation results are given to show the capability of the proposed approach. As it is demonstrated in the numerical analysis of the radial 33-bus distribution test network, the proposed placement algorithm can efficiently determine the optimal bus for connecting the WDG and is suitable for real applications.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 74
    Publication Date: 2018-09-06
    Description: Entropy, Vol. 20, Pages 672: Entropy, Measures of Distance and Similarity of Q-Neutrosophic Soft Sets and Some Applications Entropy doi: 10.3390/e20090672 Authors: Majdoleen Abu Qamar Nasruddin Hassan The idea of the Q-neutrosophic soft set emerges from the neutrosophic soft set by upgrading the membership functions to a two-dimensional entity which indicate uncertainty, indeterminacy and falsity. Hence, it is able to deal with two-dimensional inconsistent, imprecise, and indeterminate information appearing in real life situations. In this study, the tools that measure the similarity, distance and the degree of fuzziness of Q-neutrosophic soft sets are presented. The definitions of distance, similarity and measures of entropy are introduced. Some formulas for Q-neutrosophic soft entropy were presented. The known Hamming, Euclidean and their normalized distances are generalized to make them well matched with the idea of Q-neutrosophic soft set. The distance measure is subsequently used to define the measure of similarity. Lastly, we expound three applications of the measures of Q-neutrosophic soft sets by applying entropy and the similarity measure to a medical diagnosis and decision making problems.
    Electronic ISSN: 1099-4300
    Topics: Chemistry and Pharmacology , Physics
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  • 75
    Publication Date: 2018-09-06
    Description: Entropy, Vol. 20, Pages 674: Study on Mutual Information and Fractal Dimension-Based Unsupervised Feature Parameters Selection: Application in UAVs Entropy doi: 10.3390/e20090674 Authors: Xiaohong Wang Yidi He Lizhi Wang In this study, due to the redundant and irrelevant features contained in the multi-dimensional feature parameter set, the information fusion performance of the subspace learning algorithm was reduced. To solve the above problem, a mutual information (MI) and fractal dimension-based unsupervised feature parameters selection method was proposed. The key to this method was the importance ordering algorithm based on the comprehensive consideration of the relevance and redundancy of features, and then the method of fractal dimension-based feature parameter subset evaluation criterion was adopted to obtain the optimal feature parameter subset. To verify the validity of the proposed method, a brushless direct current (DC) motor performance degradation test was designed. Vibrational sample data during motor performance degradation was used as the data source, and motor health-fault diagnosis capacity and motor state prediction effect ware evaluation indexes to compare the information fusion performance of the subspace learning algorithm before and after the use of the proposed method. According to the comparison result, the proposed method is able to eliminate highly-redundant parameters that are less correlated to feature parameters, thereby enhancing the information fusion performance of the subspace learning algorithm.
    Electronic ISSN: 1099-4300
    Topics: Chemistry and Pharmacology , Physics
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  • 76
    Publication Date: 2018-09-06
    Description: Entropy, Vol. 20, Pages 670: A New Chaotic System with Stable Equilibrium: Entropy Analysis, Parameter Estimation, and Circuit Design Entropy doi: 10.3390/e20090670 Authors: Tomasz Kapitaniak S. Alireza Mohammadi Saad Mekhilef Fawaz E. Alsaadi Tasawar Hayat Viet-Thanh Pham In this paper, we introduce a new, three-dimensional chaotic system with one stable equilibrium. This system is a multistable dynamic system in which the strange attractor is hidden. We investigate its dynamic properties through equilibrium analysis, a bifurcation diagram and Lyapunov exponents. Such multistable systems are important in engineering. We perform an entropy analysis, parameter estimation and circuit design using this new system to show its feasibility and ability to be used in engineering applications.
    Electronic ISSN: 1099-4300
    Topics: Chemistry and Pharmacology , Physics
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  • 77
    Publication Date: 2018-09-06
    Description: Entropy, Vol. 20, Pages 671: Power Law Behaviour in Complex Systems Entropy doi: 10.3390/e20090671 Authors: António M. Lopes J. A. Tenreiro Machado n/a
    Electronic ISSN: 1099-4300
    Topics: Chemistry and Pharmacology , Physics
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  • 78
    Publication Date: 2018-09-06
    Description: Forests, Vol. 9, Pages 545: Landscape Diversity for Reduced Risk of Insect Damage: A Case Study of Spruce Bud Scale in Latvia Forests doi: 10.3390/f9090545 Authors: Endijs Bāders Āris Jansons Roberts Matisons Didzis Elferts Iveta Desaine Spruce bud scale (Physokermes piceae (Schrnk.) has gained attention due to recent outbreaks in the eastern Baltic Sea region—Poland, Lithuania, and Latvia. In the spring of 2010, it spread rapidly across Latvia, affecting large areas of Norway spruce stands. Therefore, the aim of our study was to assess the effects of landscape heterogeneity on the damage caused by spruce bud scale in Norway spruce stands. In this study, we evaluated landscape metrics for middle-aged (40 to 70 years old) Norway spruce-dominated stands (>70% of stand’s basal area) in four of the most affected forest massifs and two unaffected forest massifs. We used a binary logistic generalized linear mixed effects model (GLMMs) to assess the effect of environmental factors on the abundance of the spruce bud scale. Our results show that increased local diversity within 100 m of a forest patch apparently reduced the probability of spruce bud scale presence. We also found that the diversity within 1000 m of a patch was associated with an increased probability of spruce bud scale damage. A quantitative analysis of landscape metrics in our study indicated that greater landscape-scale diversity of stands may reduce insect damages.
    Electronic ISSN: 1999-4907
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
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  • 79
    Publication Date: 2018-09-06
    Description: Geosciences, Vol. 8, Pages 334: Mapping a Subsurface Water Channel with X-Band and C-Band Synthetic Aperture Radar at the Iron Age Archaeological Site of ‘Uqdat al-Bakrah (Safah), Oman Geosciences doi: 10.3390/geosciences8090334 Authors: Frances Wiig Michael J. Harrower Alexander Braun Smiti Nathan Joseph W. Lehner Katie M. Simon Jennie O. Sturm John Trinder Ioana A. Dumitru Scott Hensley Terence Clark Subsurface imaging in arid regions is a well-known application of satellite Synthetic Aperture Radar (SAR). Archaeological prospection has often focused on L-band SAR sensors, given the ability of longer wavelengths to penetrate more deeply into sand. In contrast, this study demonstrates capabilities of shorter-wavelength, but higher spatial resolution, C-band and X-band SAR sensors in archaeological subsurface imaging at the site of ‘Uqdat al-Bakrah (Safah), Oman. Despite having varying parameters and acquisitions, both the X-band and C-band images analyzed were able to identify a subsurface paleo-channel that is not visible on the ground surface. This feature was first identified through Ground Penetrating Radar (GPR) survey, then recognized in the SAR imagery and further verified by test excavations. Both the GPR and the excavations reveal the base of the paleo-channel at a depth of 0.6 m–0.7 m. Hence, both X-band and C-band wavelengths are appropriate for subsurface archaeological prospection in suitable (dry silt and sand) conditions with specific acquisition parameters. Moreover, these results offer important new insights into the paleo-environmental context of ancient metal-working at ‘Uqdat al-Bakrah and demonstrate surface water flow roughly contemporary with the site’s occupation.
    Electronic ISSN: 2076-3263
    Topics: Geosciences
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  • 80
    Publication Date: 2018-09-07
    Description: Energies, Vol. 11, Pages 2356: A Pilot Study on Geothermal Heat Pump (GHP) Use for Cooling Operations, and on GHP Site Selection in Tropical Regions Based on a Case Study in Thailand Energies doi: 10.3390/en11092356 Authors: Sasimook Chokchai Srilert Chotpantarat Isao Takashima Youhei Uchida Arif Widiatmojo Kasumi Yasukawa Punya Charusiri In order to reduce electricity consumption, the vertical loop geothermal heat pump (GHP) system coupled with a normal air conditioner was installed in an experimental room in the Parot Racha Building, Chulalongkorn University, Bangkok, Thailand for a comparative, long-term measurement program. The decrease in electricity consumption was approximately 30%. On the basis of the data derived from our measurements, the underground temperature seemed to be consistent and lower than the average outside air temperature, over two years. The underground system consisted mainly of two 50-m-long drilling wells and pipes with a total length of 170 m. The well performance was not examined, but both soil and groundwater aquifer (Bangkok aquifer) at 25 to 50 m. could be utilized for the cooling operation. Moreover, the major controlling factors of electricity consumption were found to be the outside air temperatures and the underground water circulation temperatures. In addition, we considered the geology, underground temperature, and aquifer of Bangkok concluding that almost all Bangkok areas are suitable for GHP installation, except for those where the subsurface temperature is too high compared with the outside air temperature.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 81
    Publication Date: 2018-09-07
    Description: Energies, Vol. 11, Pages 2357: Simulation of Fluid-Thermal Field in Oil-Immersed Transformer Winding Based on Dimensionless Least-Squares and Upwind Finite Element Method Energies doi: 10.3390/en11092357 Authors: Gang Liu Zhi Zheng Dongwei Yuan Lin Li Weige Wu In order to study the coupling fluid and thermal problems of the local winding in oil-immersed power transformers, the least-squares finite element method (LSFEM) and upwind finite element method (UFEM) are adopted, respectively, to calculate the fluid and thermal field in the oil duct. When solving the coupling problem by sequential iterations, the effect of temperature on the material property and the loss density of the windings should be taken into account. In order to improve the computation efficiency for the coupling fields, an algorithm, which adopts two techniques, the dimensionless LSFEM and the combination of Jacobi preconditioned conjugate gradient method (JPCGM) and the two-side equilibration method (TSEM), is proposed in this paper. To validate the efficiency of the proposed algorithm, a local winding model of a transformer is built and the fluid field is computed by the conventional LSFEM, dimensionless LSFEM, and the Fluent software. Wh