Sustainability2015, 7(2), 1542-1557; doi:10.3390/su7021542 (registering DOI) - published 30 January 2015 Show/Hide Abstract
Abstract: Although the regional differences of rural economic development can be easily determined, a challenging problem for research studies regarding rural economic development has been the inter-relatedness between different areas, and this challenge has been noted remarkably little in research data to date. As an empirical investigation, this study analyzes the spatio-temporal characteristics of rural economic development from a period beginning in 1978 to the year 2012, in the eastern coastal region of China. In order to determine the special differentiation characteristics of rural economic development, three indexes, namely the Gini coefficient (G), Tsui–Wang index (TW) and Theil index (T), were employed. To explore the inter-relatedness among the different areas, we selected a spatial autocorrelation model. The results indicated that, to a large extent, rural economic development from 1978 to 2012 in the eastern coastal region of China was greatly influenced, and the per capita annual net income changed significantly, due to the process of rapid urbanization and industrialization. Generally speaking, the annual net income constantly increased, from 87.7 USD in 1978 to 1628.1 USD in 2012. However, the calculation results indicated that the per capita income gap in the same province decreased, while the gap between the provinces presented an aggregate trend. The regional polarization widened continuously. It was also found that the spatial positive autocorrelation for the regional economy was significant, with a waving and ascending trend, and the neighbor effect of regional economic growth was continuously strengthened. Qualitative analysis of the driving mechanism was applied, and it was determined that there are three primary factors affecting the development of the rural regions, namely resource endowments, economic location and policies.
Sustainability2015, 7(2), 1516-1541; doi:10.3390/su7021516 (registering DOI) - published 30 January 2015 Show/Hide Abstract
Abstract: Companies have been aware of the benefits of developing Cluster Supply Chains (CSCs), and they are spending a great deal of time and money attempting to develop the new business pattern. Yet, the traditional techniques for identifying CSCs have strong theoretical antecedents, but seem to have little traction in the field. We believe this is because the standard techniques fail to capture evolution over time, nor provide useful intervention measures to reach goals. To address these problems, we introduce an agent-based modeling approach to evaluate CSCs. Taking collaborative procurement as research object, our approach is composed of three parts: model construction, model instantiation, and computational experiment. We use the approach to explore the service charging policy problem in collaborative procurement. Three kinds of service charging polices are compared in the same experiment environment. Finally, “Fixed Cost” is identified as the optimal policy under the stable market environment. The case study can help us to understand the workflow of applying the approach, and provide valuable decision support applications to industry.
Sustainability2015, 7(2), 1503-1515; doi:10.3390/su7021503 (registering DOI) - published 30 January 2015 Show/Hide Abstract
Abstract: This paper introduces the concept of apparent motion, and by examining the characteristics of apparent motion and of velocity vectors, puts forward a new speed reduction method in tunnels. Finally, we verify this effect through a simulation experiment. The experiment first used 3DMAX to make simulation videos with apparent motion grating installed on the tunnel wall, and then took the “stable same, direction movement” proportion of perception responses as the index to determine the optimal form of apparent motion. Using the observations of six males and two females, the experiments show that, with a space layout of two bright, two dark or four bright, four dark, a stimulus separation (SS) of 2 or 4 m, and stimulus onset asynchrony (SOA) of 60, 120, 180 or 240 ms, participants tended to perceive apparent motion as “stable same, direction movement”. Based on the above, 16 combinations of grating were adopted as optimal forms. By using the Forced-Choice Method, the experiments showed that the best parameters of apparent motion grating for speed reduction are: two bright, two dark, SS as 4 m and SOA as 60 ms. Under these conditions, the average perceived speed of eight observers reaches the maximum; meanwhile, the standard deviation is lower than that of the four dark, four bright case.
Sustainability2015, 7(2), 1483-1502; doi:10.3390/su7021483 - published 29 January 2015 Show/Hide Abstract
Abstract: The main objective of this paper is to present the factors with influence on the sustainable university management and the relationships between them. In the scientific approach we begin from a graphical model, according to which the extracurricular activities together with internal environmental factors influence students’ involvement in such activities, the university attractiveness, their academic performance and their integration into the socially-economic and natural environment (components related with sustainable development). The model emphasizes that individual performances, related to students’ participation in extracurricular activities, have a positive influence on the sustainability of university management. The results of the study have shown that the university sustainability may be influenced by a number of factors, such as students’ performance, students’ involvement in extracurricular activities or university’s attractiveness and can in turn influence implicitly also the sustainability of university management. The originality of the paper consists in the relationships study using the modeling method in general and informatics tools of modeling in particular, as well as through graphical visualization of some influences, on the sustainability university management.
Sustainability2015, 7(2), 1459-1482; doi:10.3390/su7021459 - published 28 January 2015 Show/Hide Abstract
Abstract: Despite the unprecedented rate of urbanization throughout the world, human society is still facing the challenge of coordinating urban socioeconomic development and ecological conservation. In this article, we integrated socioeconomic data and spatial metrics to investigate the coupling relationship between intensive land use (ILU) system and landscape ecological security (LES) system for urban sustainable development, and to determine how these systems interact with each other. The values of ILU and LES were first calculated according to two evaluation subsystems under the pressure-state-response (PSR) framework. A coupling model was then established to analyze the coupling relationship within these two subsystems. The results showed that the levels of both subsystems were generally increasing, but there were several fluctuation changes in LES. The interaction in each system was time lagged; urban land use/cover change (LUCC) and ecosystem transformation were determined by political business cycles and influenced by specific factors. The coupling relationship underwent a coordinated development mode from 1992–2012. From the findings we concluded that the coupling system maintained a stable condition and underwent evolving threshold values. The integrated ILU and LES system was a coupling system in which subsystems were related to each other and internal elements had mutual effects. Finally, it was suggested that our results provided a multi-level interdisciplinary perspective on linking socioeconomic-ecological systems. The implications for urban sustainable development were also discussed.
Sustainability2015, 7(2), 1446-1458; doi:10.3390/su7021446 - published 28 January 2015 Show/Hide Abstract
Abstract: The environmental crisis and the need to find renewable fuel alternatives have made production of biofuels an important priority. At the same time, the increasing production of food waste is an important environmental issue. For this reason, production of ethanol from food waste is an interesting approach. Volumes of food waste are reduced and ethanol production does not compete with food production. In this work, we evaluated the possibility of using source-separated household food waste for the production of ethanol. To minimize the cost of ethanol production, the hydrolytic enzymes that are necessary for cellulose hydrolysis were produced in-house using the thermophillic fungus Myceliophthora thermophila. At the initial stage of the study, production of these thermophilic enzymes was studied and optimized, resulting in an activity of 0.28 FPU/mL in the extracellular broth. These enzymes were used to saccharify household food waste at a high dry material consistency of 30% w/w, followed by fermentation. Ethanol production reached 19.27 g/L with a volumetric productivity of 0.92 g/L·h, whereas only 5.98 g/L of ethanol was produced with a volumetric productivity of 0.28 g/L·h when no enzymatic saccharification was used.