Narrow Results

Despite the promising characteristics of Dielectric Elastomel Actuator (DEA) as a practical soft actuator, the need of high voltage for its operation prevents the successful fabrication of a practical DEA, that is, the high voltage generation takes a bulky and costly power supply. Induction of complex shape change motion of DEA such as oscillatory shape change takes even a more bulky and costly multipurpose power supply. It is a serious practical issue to be overcome. In our latest study, however, we could build a simple DEA system which exhibited a relatively complex and autonomous oscillatory shape change merely under a constant voltage, though the voltage needed was high. This successful outcome must broaden the potential usefulness of DEA as a practical soft actuator.

In recent years, as the international community pays increasing attention to disaster prevention and reduction, study on vulnerability has become a new focus in the science of disaster, and it gradually becomes a consideration in strategy-making for sustainable social development. Understanding of vulnerability has become a prerequisite for grasping the nature of disasters, and it is also an area where humans can make a difference in disaster prevention and mitigation. Based on historical disasters and the concepts of vulnerability, this study applies the CCR model, one of the most basic Data Envelopment Analysis (DEA) models, to analyze the pattern of variation regarding agricultural vulnerability to floods in Shanghai suburban areas. The results prove the following: chronologically, the overall vulnerability degrees of Shanghai suburbs listed in the descending order are $1991>1983>1984>1981>1985>1979>1986>1990>1980>1989>1987>1988$; spatially, based on the averages recorded in 2013, the vulnerability levels of Shanghai suburban districts are Nanhui $>$ Jinshan $>$ Songjiang $>$ Baoshan $>$ Qingpu $>$ Pudong $>$ Jiading $>$ Fengxian. The results are basically consistent with the fact. Based on the characteristics of each district’s vulnerability to floods, some suggestions for flood prevention and mitigation are provided. The assessment models of flood vulnerability are simple and can be used for vulnerability analysis of natural disasters at regional or national levels. The assessment method adopted in this paper contributes to a deeper understanding of agricultural vulnerability to floods in Shanghai and provides a scientific base for the decision-making of related departments.

The leisure agriculture in suburban towns provides important space for citizens to carry out leisure activities. This paper takes Xinkou town in Tianjin city as an example to analyze the development efficiency of leisure agriculture in suburban towns. On the premise of establishing the indicators for evaluating the development efficiency of leisure agriculture in Xinkou town, this paper first uses the data envelopment analysis (DEA) to measure the input and output indicators of leisure agriculture in 18 natural villages in Xinkou town, and calculates the comprehensive technical efficiency, target values, redundancy and returns to scale of leisure agriculture, and then evaluates the development efficiency of leisure agriculture in Xinkou town. Furthermore, by using the high/low clustering tool under the ArcGIS spatial statistics module, this paper conducts a high/low clustering analysis of the development efficiency of leisure agriculture in 18 natural villages of Xinkou town, and figures out the reasons for the high/low clustering of natural villages in Xinkou town spatially. After the research and analysis, the following conclusions are drawn: From the input–output perspective, except for Zhengzhuangzi village, Diliubu village, Yuejiakai village, and Dangcheng village, the development efficiency of leisure agriculture in other villages is relatively low due to their poor resource foundations, or deficiencies in management experience and transportation location. The development of leisure agriculture in Xinkou town is unbalanced, showing a pattern of polarized clusters: Diliubu village and Shuigaozhuang village form the most obvious high-value cluster, while Xiaoshawo village, Bijia village and Xuanjiayuan village form the most obvious low-value cluster, where the southeast corner of Xinkou town registers the lowest development efficiency value of leisure agriculture because it is far away from the town center and the main transportation arteries, and falls short of high-quality pastoral scenery. For the future development of leisure agriculture in Xinkou town, it is supposed to optimize the land use policy, provide active support to the competitive industrial and commercial capital, non-governmental capital, rural collective economic organizations, farmers’ cooperatives, and family farms, strengthen the in-depth integration of industries, improve the support system for new-type leisure agriculture, and build leisure agriculture brands with local features.