ALBERT

Description: Energies, Vol. 11, Pages 2539: Mine Strata Pressure Characteristics and Mechanisms in Gob-Side Entry Retention by Roof Cutting under Medium-Thick Coal Seam and Compound Roof Conditions Energies doi: 10.3390/en11102539 Authors: Xingen Ma Manchao He Jiong Wang Yubing Gao Daoyong Zhu Yuxing Liu Coal is among the most important energy sources, and gob-side entry retention by roof cutting (GERRC) is an innovative non-pillar mining technique that can effectively increase coal recovery rates and avoid coal wastage. To investigate the characteristics of mine strata pressure using the GERRC technique, a field case study under conditions involving a medium-thick coal seam and a compound roof was performed, and the mine strata behavior mechanisms were studied by theoretical analysis. Field monitoring shows that the distributions of the weighting step and strength along the longwall working face are asymmetrical. The periodic weighting length on the entry retaining side is longer than that on the other sides of the longwall working face, and the average increase is appropriately 4 m. Compared to the other sides of the longwall, on the entry retaining side, the periodic weighting strength is weaker, the average pressure is reduced by 2.1 MPa, and the peak pressure is reduced by 10.2 MPa. The lateral distance affected by roof cutting along the longwall is approximately 29.75 m, and the closer to the cutting slit, the more significant the roof cutting effect is. The retained entry becomes stable when it is more than 230 m behind the mining face, and the final cross section of the retained entry can meet the reuse demand of the next mining face. Theoretical analysis shows that the roof pressure mechanism in GERRC can be explained using cantilever beam theory. Within the area affected by roof cutting, the thickness of the immediate roof increases, and the suspension plate length of the roof immediately behind the longwall decreases. Then, the gangue pile in the goaf behind the longwall formed by the immediate roof’s collapse and expansion can support the main roof and other overlying strata much better. Therefore, the rotational breaking angle of the main roof is smaller, the periodic weighting step strength increases, and the periodic weighting decreases. According to the structural state of the surrounding rocks during the entire entry retaining process, the retained entry can be divided into coal support, dynamic pressure and stable entry areas.

Description: Energies, Vol. 11, Pages 2536: Application of Wind as a Renewable Energy Source for Passive Cooling through Windcatchers Integrated with Wing Walls Energies doi: 10.3390/en11102536 Authors: Payam Nejat Fatemeh Jomehzadeh Hasanen Mohammed Hussen John Kaiser Calautit Muhd Zaimi Abd Majid Generally, two-third of a building’s energy is consumed by heating, ventilation and air-conditioning systems. One green alternative for conventional air conditioner systems is the implementation of passive cooling. Wing walls and windcatchers are two prominent passive cooling techniques which use wind as a renewable resource for cooling. However, in low wind speed regions and climates, the utilization of natural ventilation systems is accompanied by serious uncertainties. The performance of ventilation systems can be potentially enhanced by integrating windcatchers with wing walls. Since previous studies have not considered this integration, in the first part of this research the effect of this integration on the ventilation performance was assessed and the optimum angle was revealed. However, there is still gap of this combination; thus, in the second part, the impact of wing wall length on the indoor air quality factors was evaluated. This research implemented a Computational Fluid Dynamics (CFD) method to address the gap. The CFD simulation was successfully validated with experimental data from wind tunnel tests related to the previous part. Ten different lengths from 10 cm to 100 cm were analyzed and it was found that the increase in wing wall length leads to a gradual reduction in ventilation performance. Hence, the length does not have a considerable influence on the indoor air quality factors. However, the best performance was seen in 10 cm, that could provide 0.8 m/s for supply air velocity, 790 L/s for air flow rate, 39.5 1/h for air change rate, 107 s for mean age of air and 92% for air change effectiveness.

Description: IJERPH, Vol. 15, Pages 2089: Seroprevalence and Determinants Associated with Mumps Antibodies after 20 Years of MMR Vaccination in Urban Area of Shanghai, China International Journal of Environmental Research and Public Health doi: 10.3390/ijerph15102089 Authors: Hong Pang Yibiao Zhou Wensui Zhao Qingwu Jiang A resurgence of the mumps epidemic in highly vaccinated populations has occurred in recent years in many countries. This study aimed to evaluate the seroprevalence to mumps in urban areas of Shanghai, where a measles-mumps-rubella (MMR) vaccination had been implemented for 20 years. Mumps IgG antibodies were tested in 2662 residual sera from all ages in an urban area of Shanghai. A linear regression method was performed to assess the persistence of mumps antibodies after MMR vaccination. A logistic regression method was used to analyze the variables associated with seronegative sera. The overall age- and gender-adjusted seroprevalence of mumps antibodies reached 90% (95% CI: 90.0–90.2). The antibody concentration declined significantly in the first eight years after the second dose of MMR. The multivariate analysis identified that males, age groups, especially 17–19 years and no dose of vaccination, as well as one dose of vaccination, as factors associated with an increased risk of seronegative sera. A high seroprevalence to mumps has been achieved in the urban areas of Shanghai. A declining antibody level of mumps after the second dose of MMR may put a potential risk of recurrence of mumps. The two-dose MMR vaccine schedule is superior to one-dose schedule for mumps control.

Description: IJERPH, Vol. 15, Pages 2090: Priorization of River Restoration by Coupling Soil and Water Assessment Tool (SWAT) and Support Vector Machine (SVM) Models in the Taizi River Basin, Northern China International Journal of Environmental Research and Public Health doi: 10.3390/ijerph15102090 Authors: Juntao Fan Mengdi Li Fen Guo Zhenguang Yan Xin Zheng Yuan Zhang Zongxue Xu Fengchang Wu Identifying priority zones for river restoration is important for biodiversity conservation and catchment management. However, limited data due to the difficulty of field collection has led to research to better understand the ecological status within a catchment and develop a targeted planning strategy for river restoration. To address this need, coupling hydrological and machine learning models were constructed to identify priority zones for river restoration based on a dataset of aquatic organisms (i.e., algae, macroinvertebrates, and fish) and physicochemical indicators that were collected from 130 sites in September 2014 in the Taizi River, northern China. A process-based model soil and water assessment tool (SWAT) was developed to model the temporal-spatial variations in environmental indicators. A support vector machine (SVM) model was applied to explore the relationships between aquatic organisms and environmental indicators. Biological indices among different hydrological periods were simulated by coupling SWAT and SVM models. Results indicated that aquatic biological indices and physicochemical indicators exhibited apparent temporal and spatial patterns, and those patterns were more evident in the upper reaches compared to the lower reaches. The ecological status of the Taizi River was better in the flood season than that in the dry season. Priority zones were identified for different hydrological seasons by setting the target values for ecological restoration based on biota organisms, and the results suggest that hydrological conditions significantly influenced restoration prioritization over other environmental parameters. Our approach could be applied in other seasonal river ecosystems to provide important preferences for river restoration.

Description: Sustainability, Vol. 10, Pages 3395: Market Segmentation by Travel Motivations under a Transforming Economy: Evidence from the Monte Carlo of the Orient Sustainability doi: 10.3390/su10103395 Authors: Tiantian (Tiana) Shi Xiaoming (Rose) Liu Jun (Justin) Li Macau, the world’s largest casino hub with the largest gambling revenues, has received increasing attention as a research focus. Macau attracts more and more Chinese outbound tourists each year due to its gambling industry monopoly in Greater China. Macau is positioning itself as a ‘world center of tourism and leisure’ and has set out plans to become a broader-based tourist destination with economic diversification. Thus, an understanding of people’s varied motivations plays an important role in the current status of an environment with a moderate diversification of economic development. The objective of this study is to classify the outbound mainland Chinese tourists in Macau into more homogeneous subgroups on the basis of their travel motivations. Thirteen motivation items are extracted into four factors (namely knowledge and culture, relaxation, entertainment and gambling, and prestige) through exploratory factor analysis. Three distinct market segments are identified—freedom seekers, multi-purpose seekers, and fun and special interest in gambling seekers—based on a cluster analysis using k-means methodology. This study also presents the socio-demographic and trip characteristic differences among these three segments.

Description: Sustainability, Vol. 10, Pages 3390: Fiscal Adjustment Programs versus Socially Sustainable Competitiveness in EU Countries Sustainability doi: 10.3390/su10103390 Authors: Cristian Socol Marius Marinas Aura Gabriela Socol Dan Armeanu After implementing harsh austerity measures during 2008–2011, in the period 2012–2014 the fiscal adjustment programs also involved social equity measures, the quantitative fiscal consolidation being changed into a qualitative one—a reduction of the structural budget deficit accompanied by an improvement of social sustainability indicators. The 2015–2017 period shows mixed evolutions in terms of social progress brought by the recovery of the economic potential lost during the crisis. This research analyzes the sustainability of economic competitiveness dynamics from a social viewpoint during 2012–2014. In this paper, we analyze the way in which the economic and social components of fiscal adjustment programs are dynamically balanced in 24 EU member states. We identify four clusters of countries depending on the relationship between fiscal consolidation/fiscal stimulation and the social dynamics of the sustainability adjusted global competitiveness index. We found that under the pressure of “fiscal adjustment fatigue” caused by tough austerity programs in the period 2008–2011, most of the European countries completed the fiscal adjustment packages with measures to improve the social situation between 2012 and 2017. The fiscal consolidation programs have become more balanced from the perspective of the combination of budgetary austerity—social equity measures. Furthermore, we analyze how some countries on the EU periphery (Central and Eastern Europe, Baltic countries and Portugal, Ireland and Greece, countries that have joined the EU with a lower level of development) are experiencing or not an improvement in the social sustainability generated by the measures aimed at stimulating the economic growth implemented during 2012–2017. To conclude, we proposed a few pillars that could be integrated if an “ideal adjustment program” is to be achieved.

Description: Sustainability, Vol. 10, Pages 3393: Responsible Decision making for Sustainable Motivation Sustainability doi: 10.3390/su10103393 Authors: Martina Blašková Irena Figurska Ruta Adamoniene Kristína Poláčková Rudolf Blaško This article examines motivation and the quality of decision making’s effect on motivation as important preconditions for organizational sustainability. The article is focused on an examination of the content and intensity of perceived motivation, and the forms of decisions that were made while motivating people. Motivation (from a theoretical and empirical point of view) is related to crucial processes of human potential development and motivation. The analysis, synthesis and generalization of knowledge related to sustainability, motivation and decision making in human potential motivation are presented in the theoretical part of the article. The empirical part presents the results of sociological questionnaire, focusing on the area of decision making in motivation that was carried out on sample of respondents in the Slovak Republic (n = 500), Poland (n = 390) and Lithuania (n = 226). The results confirm a strong correlation between the level of the motivation and the quality of key processes of development of human potential (leadership, appraisal, communication, and the creation of an atmosphere of trust). In all examined countries and processes, the calculated values of the chi-square test were significantly higher than the table value (level of significance = 0.05). The section describing the results contains a proposed content-componential model of decision making in affecting and building sustainable motivation.

Description: Water, Vol. 10, Pages 1315: Developing an EFDC and Numerical Source-Apportionment Model for Nitrogen and Phosphorus Contribution Analysis in a Lake Basin Water doi: 10.3390/w10101315 Authors: Hui Bai Yan Chen Dong Wang Rui Zou Huanzhen Zhang Rui Ye Wenjing Ma Yunhai Sun The numerical source-apportionment model is an efficient and useful method for analyzing water-quality responses to nutrient loading in rivers and lakes. In this study, the Environmental Fluid Dynamic Code (EFDC) and numerical source-apportionment model were applied to Lake Bali in Jiujiang City, China to predict the contributions of various pollution sources to the lake at any time and position. We calibrated and validated the model by comparing its predictions with observed hydrodynamic and water-quality parameters from 2014 to 2015. Application of the calibrated model to simulate water-quality responses to a pollution source showed that the contribution of a pollution source to water quality in the lake has strong spatial heterogeneity. The results provide useful information for the optimization of pollution load reduction in Lake Bali and can be used to determine the most effective implementation of its pollution-control plan. The model built in this study can also be used for pollution source-apportionment in other urban lakes and is superior to other traditional source-apportionment models.

Description: Water, Vol. 10, Pages 1316: Greener Method for the Removal of Toxic Metal Ions from the Wastewater by Application of Agricultural Waste as an Adsorbent Water doi: 10.3390/w10101316 Authors: Rabia Baby Shaikh Bullo Saifullah Fawad ur Rehman Ruqia Iqbal Shaikh The presence of inorganic pollutants such as metal ions (Ni2+, Pb2+, Cr6+) in water, probably by long-term geochemical changes and from the effluents of various industries, causes diseases and disorders (e.g., cancer, neurodegenerative diseases, muscular dystrophy, hepatitis, and multiple sclerosis). Conventional methods for their removal are limited by technical and economic barriers. In biosorption, low-cost and efficient biomaterials are used for this purpose. In this study, Brassica Campestris stems from the agriculture waste and has been used for the removal of Ni2+, Cr6+ and Pb2+ ions from an aqueous solution containing all the ions. Effect of different parameters, e.g., pH, contact time, metal ion initial concentration, adsorbent dose, agitation rate and temperature were analyzed and optimized. The adsorbent worked well for removal of the Pb2+ and Cr6+ as compared to Ni2+. The atomic absorption spectrophotometer (AAS) and FTIR investigation of adsorbent before and after shows a clear difference in the adsorbent capability. The highest adsorption percentage was found at 98%, 91%, and 49% respectively, under the optimized parameters. Furthermore, the Langmuir isotherm was found better in fitting to the experimental data than that of the Freundlich isotherm.

Description: Sustainability, Vol. 10, Pages 3389: Linkage Analysis among China’s Seven Emissions Trading Scheme Pilots Sustainability doi: 10.3390/su10103389 Authors: Xuedi Li Jie Ma Zhu Chen Haitao Zheng This paper focuses on the time-varying correlation among China’s seven emissions trading scheme markets. Correlation analysis shows a weak connection among these markets for the whole sample period, which spans from 9 June 2014 to 30 June 2017. The return rate series of the seven markets show the characteristics of a fat-tailed and skewed distribution, and the Vector Autoregression (VAR) residuals present a significant Autoregressive Conditional Heteroscedasticity (ARCH) effect. Therefore, we adopt Vector Autoregression Generalized ARCH model with Dynamic Conditional Correlation (VAR-DCC-GARCH) to capture the time-varying correlation coefficients. The results of the VAR-DCC-GARCH show that the conditional correlation coefficients fluctuate fiercely over time. At some points, the different markets present a significant correlation with the value of the even peaks of the coefficient at 0.8, which indicates that these markets are closely connected. However, the connection between each market does not last long. According to the actual situation of China’s regional carbon emission markets, policy factors may explain most of the temporary, significant co-movement among markets.