ALBERT

Description: Simultaneously protecting the environment and promoting the economy are two critical dimensions for sustainable development. Carbon productivity is popularly used in assessing the environmental and economic efficiency over time, and is deemed as the appropriate indicator of sustainable development. Given the prominent contribution of energy consumption to sustainable development, this study incorporates energy consumption into the Log Mean Divisia Index (LMDI) decomposition model to explore the main factors influencing carbon productivity change. Based on the data from 19 industries in Beijing from 2013 to 2016, this study then reports the carbon productivities and their changes. Energy productivity change is the main cause of carbon productivity changes, and its correlation with carbon productivity change is significantly positive, whereas there is a weak correlation and no significant difference in energy consumption per unit of carbon emissions. Although the average carbon productivities in all 19 industries increased year over year in Beijing, the average level could be further promoted by improving energy productivity. The carbon productivities of the primary and secondary industries are less than the average, and far below the tertiary industry level. For the primary industry, increasing economic levels is conducive to improving carbon productivity; for secondary industry, reducing energy consumption and enhancing energy efficiency are most effective; and for tertiary industry, maintaining an outstanding performance will guarantee sustainable development in Beijing. This study has defined carbon productivity change from the energy consumption perspective and for the first time, comprehensively measured it for all industries in Beijing. The results are expected to assist these industries to essentially improve productivity performance and thus improve development sustainability.

Description: Sustainable development has become the biggest concern of the semiconductor industry, which plays a vital role not only in technology breakthroughs, but also by serving as an enabler for sustainability. This study combines Analytic Hierarchy Process (AHP) and additive network Data Envelopment Analysis (DEA) to measure the sustainable performance which are derived from business growth stage and energy utilization stage through the parametric linear program. Meanwhile, this method makes up the disadvantage of the weighting technique used additive decomposition approach to the two-stage network and avoids biasing toward the second stage. The findings demonstrate that Taiwan’s semiconductor manufacturing sector has exhibited a steady increase in its overall trend of sustainability performance. According to the stage-level performance results, the performance of business growth is better than energy utilization. However, the changing trend of overall sustainability performance is through a steady increase from environmental efficiency and not from economic efficiency.

Description: The Brushless Doubly Fed Induction Generator (BDFIG) has huge potential for wind power systems due to its high reliability and low maintenance cost. To add inertia for system stability enhancement, as well as to maintain the uninterrupted operation during symmetrical grid faults, this study proposes a Virtual Synchronous Control (VSC) with a transient current compensation strategy for BDFIG. The proposed VSC is realized by regulating the virtual inner electrical potential and angular velocity of BDFIG under Control Winding (CW) current oriented vector control, and compensating for the transient CW current to weaken the transient inner electrical potential under symmetrical grid faults. Modeling and analysis of such a VSC strategy are presented in this paper, and a simulation is also made to compare the performances of existing and proposed VSC strategies. It is shown that the merits of the proposed VSC can enhance the fault ride through the ability of the BDFIG system and support the recovery of grid voltage.

Description: Due to the fast electric control of the doubly-fed induction generator (DFIG) when experiencing power grid disturbance or turbulent wind, the flexible drive chain of the wind turbine (WT) generates long-term torsional vibration, which shortens the service life of the drive chain. The torsional vibration causes fatigue damage of the gearbox and affects power generation. In this paper, a two-channel active damping control measure is proposed. The strategy forms a new WT electromagnetic torque reference value through two channels: one is a proportion integration differentiation (PID) damping term with frequency difference, which is used to reduce torsional vibration caused by frequency difference between fan and shafting; the other adopts the torsional vibration angle (θs) as the feedback signal, and an additional damping term is formed by bandpass filter (BPF) and trap filter (BRF). The strategy can increase the electromagnetic torque and suppress the torsional vibration of the drive chain. Finally, modeling and simulation using MATLAB/Simulink show that the method can effectively suppress the torsional vibration of the drive chain without affecting power generation.

Description: A new carbon-coated nickel sulfides electrode material (NST/CNTs@C) has been synthesized through an easy-to-operate process: NiS2/CNTs which was prepared by a hydrothermal method reacted with BTC (1,3,5-benzenetricarboxylic acid) under the condition of water bath heating to obtain the precursor, and then the precursor was calcined in 450 °C under a nitrogen atmosphere to obtain NST/CNTs@C. The electrochemical performance of NST/CNTs@C has been greatly improved because the formation of a carbon-coated layer effectively increased the specific surface area, reduced the charge transport resistance and inhibited the morphological change of nickel sulfides in the charge–discharge process. Compared with pure NiS2 and NiS2/CNTs, NST/CNTs@C presented great specific capacitance (620 F·g−1 at a current density of 1 A·g−1), better cycle stability (49.19% capacitance retention after 1000 cycles) and more superior rate capability (when the current density was raised to 10 A·g−1 the specific capacitance remained 275 F·g−1).

Description: Tourism has rapidly developed into one of the world’s largest industries, and represents a new growth point for stimulating a region’s economic and social development. Therefore, a clear understanding of the interactive relationship between the tourism industry, the economy and the environment, as well as the potential mechanisms involved, can play an important role in improving the coordination between these three elements and forming a sustainable development policy. By utilizing quantitative analysis methods and models, this study uses Qingyang City, Gansu Province, as a case study, and tests the relationship between the development of the tourism industry, the economy and the environment. This study makes a number of important conclusions: (1) a mutually promoting relationship does not exist between the development of the tourism industry and economic growth; instead, a unidirectional relationship is found between the two elements. Similarly, a mutually promoting relationship does not exist between the development of the tourism industry and environmental quality; rather, a unidirectional relationship is found between the two elements. (2) The “curse effect” on economic growth imposed by the development of the tourism industry is found to exist. The development of the tourism industry not only exerts a direct negative influence on economic growth, but also adversely affects it in an indirect way through its influence over some transmission factors. Additionally, the curse effect on the environment imposed by the development of the tourism industry is also found to exist. The development of the tourism industry not only imposes a direct negative influence on the environment, but also adversely affects it in an indirect way through its influence over some transmission factors. (3) During the process of regional development, the relationship between the tourism industry, the economy and the environment needs to be correctly addressed. Through effective policies, it should be possible to realize the coordination of and sustainable development between the tourism industry, the economy and the environment.

Description: In a city, housing price varies with location. Thus, housing price plays an important role in detecting the spatial pattern of the city. Spatial interpolation methods have been widely used for simulating and predicting urban housing prices. In this paper, the Ordinary Kriging interpolation method is used for producing the digital elevation model (DEM) of urban housing prices. Based on the three-dimensional DEM of urban housing price, this paper develops a novel approach for geo–visual analytics of urban housing prices. To investigate and visualize the spatial morphology of housing price, we design the Water-flooding, Section-cutting and Belt-floating methods, and implement these methods with the 3D-analyst module in GIS environment. Then, we take Wuhan City as a case, apply this approach to analyze the complex spatial morphologic characteristics of the DEM for housing price and visualize the results from the multidimensional perspectives. The results show that the Water-flooding method effectively supports the investigation of the top areas of surface changes; Section-cutting method performs well in examining the profile or cross-section of the urban housing surface; and Belt-floating method is helpful for detecting the spatial variance of the urban housing surface through the routes of specific lines. The results demonstrate that the proposed approach works better than traditional methods in describing the complex spatial morphology of urban housing prices, and has an advantage in visualizing the analysis results.

Description: In this paper, we present a convenient and economical method to fabricate a silver (Ag)-film semi-coated polystyrene (PS) nanosphere array substrate for surface-enhanced Raman spectroscopy (SERS). The SERS substrate was fabricated using the modified self-assembled method combined with the vacuum thermal evaporation method. By changing the thickness of the Ag film, the surface morphology of the Ag film coated on the PS nanospheres can be adjusted to obtain the optimized localized surface plasmonic resonance (LSPR) effect. The 3D-finite-difference time-domain simulation results show that the SERS substrate with an Ag film thickness of 10 nm has tens of times the electric field intensity enhancement. The Raman examination results show that the SERS substrate has excellent reliability and sensitivity using rhodamine-6G (R6G) and rhodamine-B (RB) as target analytes, and the Raman sensitivity can reach 10−10 M. Meanwhile, the SERS substrate has excellent uniformity based on the Raman mapping result. The Raman enhancement factor of the SERS substrate was estimated to be 5.1 × 106. This kind of fabrication method for the SERS substrate may be used in some applications of Raman examination.