A key solution to urban and global sustainability is effective planning of sustainable urban development, for which geo-techniques especially cellular automata(CA) models can be very informative. However, existing CA ...A key solution to urban and global sustainability is effective planning of sustainable urban development, for which geo-techniques especially cellular automata(CA) models can be very informative. However, existing CA models for simulating sustainable urban development, though increasingly refined in modeling urban growth, capture mostly the environmental aspect of sustainability. In this study, an adaptable risk-constrained CA model was developed by incorporating the social-ecological risks of urban development. A three-dimensional risk assessment framework was proposed that explicitly considers the environmental constraints on, system resilience to, and potential impacts of urban development. The risk-constrained model was then applied to a case study of Sheyang County, Jiangsu Province in the eastern China. Comparative simulations of urban development in four contrasting scenarios were conducted, namely, the environmental suitability constrained scenario, the ecological risk constrained scenario, the social risk constrained scenario, and the integrated social-ecological risk constrained scenario. The simulations suggested that considering only environmental suitability in the CA simulation of urban development overestimated the potential of sustainable urban growth, and that the urbanization mode changed from city expansion that was more constrained by social risks to town growth that was more constrained by ecological risks. Our risk-constrained CA model can better simulate sustainable urban development; additionally, we provide suggestions on the sustainable urban development in Sheyang and on future model development.展开更多
Ionic electroactive polymers (IEAPs) are a category of intelligent soft materials exhibiting large displacement under electric excitation, based on inner ion or solvent transport. Due to their unique advantages such...Ionic electroactive polymers (IEAPs) are a category of intelligent soft materials exhibiting large displacement under electric excitation, based on inner ion or solvent transport. Due to their unique advantages such as flexibility, low driving voltage, large bending displacement and aquatic-environment adaptability, IEAPs have been documented as very promising actuators for the applications in bionic robots. This review presents an analysis to the current research status of IEAPs exploited in bionic robots. According to the specific bionic parts, those robots are divided into four classes: imitation of fins, limbs, joints and trunks. Their dimension, weight, voltage amplitude, frequency and maximum speed were summarized to show the optimum design range. The results show that the approach velocity of the current robots were higher (〉 35 mm· s-1) when the robot weighted 60 g - 180 g and the body was 90 mm - 130 mm long. For voltage from 1 V - 3 V and frequencies from 0.7 Hz - 1.2 Hz, the speed was relatively higher (〉 35 mm·s-1).To some extent, the maximum speed decreases when the area of the IEAP material used in bionic robot increases. For underwater circumstances, IEAP materials are most suitable for designing bionic robots swimming with Body and/or Caudal Fin (BCF). This review provides important guidance for the design of lEAP bionic robots.展开更多
In this review we have summarized some recent results mainly reported by our group that focused on the development of smart gating nanochannels based on polymer films. These nanochannels were prepared using a track-et...In this review we have summarized some recent results mainly reported by our group that focused on the development of smart gating nanochannels based on polymer films. These nanochannels were prepared using a track-etch process. The responsive materials/molecules and modification methods/techniques have also been demonstrated, from which we have obtained a series of smart gating nanochannels that can respond to single/dual external stimuli, e.g., pH, ion, temperature, light, and so on. These studies utilize responsive behaviors to regulate ionic transport properties inside a single nanochannel and demonstrate the fea-sibility of designing other smart nanodevices in the future.展开更多
基金Under the auspices of the Special Research Funds for Public Welfare,Ministry of Land and Resources of China(No.201511001-03)the Open Fund of Key Laboratory of Coastal Zone Exploitation and Protection,Ministry of Land and Resource of China(No.2017CZEPK03)
文摘A key solution to urban and global sustainability is effective planning of sustainable urban development, for which geo-techniques especially cellular automata(CA) models can be very informative. However, existing CA models for simulating sustainable urban development, though increasingly refined in modeling urban growth, capture mostly the environmental aspect of sustainability. In this study, an adaptable risk-constrained CA model was developed by incorporating the social-ecological risks of urban development. A three-dimensional risk assessment framework was proposed that explicitly considers the environmental constraints on, system resilience to, and potential impacts of urban development. The risk-constrained model was then applied to a case study of Sheyang County, Jiangsu Province in the eastern China. Comparative simulations of urban development in four contrasting scenarios were conducted, namely, the environmental suitability constrained scenario, the ecological risk constrained scenario, the social risk constrained scenario, and the integrated social-ecological risk constrained scenario. The simulations suggested that considering only environmental suitability in the CA simulation of urban development overestimated the potential of sustainable urban growth, and that the urbanization mode changed from city expansion that was more constrained by social risks to town growth that was more constrained by ecological risks. Our risk-constrained CA model can better simulate sustainable urban development; additionally, we provide suggestions on the sustainable urban development in Sheyang and on future model development.
基金The authors acknowledge the financial support from the National Natural Science Foundation of China (No. 51605131), National Natural Science Foundation of China (No. 11674354), Natural Science Foundation of Anhui Province, China (No. 1608085QE100), and Fundamental Research Funds for the Central Universities (No. JZ2016HGTB0711).
文摘Ionic electroactive polymers (IEAPs) are a category of intelligent soft materials exhibiting large displacement under electric excitation, based on inner ion or solvent transport. Due to their unique advantages such as flexibility, low driving voltage, large bending displacement and aquatic-environment adaptability, IEAPs have been documented as very promising actuators for the applications in bionic robots. This review presents an analysis to the current research status of IEAPs exploited in bionic robots. According to the specific bionic parts, those robots are divided into four classes: imitation of fins, limbs, joints and trunks. Their dimension, weight, voltage amplitude, frequency and maximum speed were summarized to show the optimum design range. The results show that the approach velocity of the current robots were higher (〉 35 mm· s-1) when the robot weighted 60 g - 180 g and the body was 90 mm - 130 mm long. For voltage from 1 V - 3 V and frequencies from 0.7 Hz - 1.2 Hz, the speed was relatively higher (〉 35 mm·s-1).To some extent, the maximum speed decreases when the area of the IEAP material used in bionic robot increases. For underwater circumstances, IEAP materials are most suitable for designing bionic robots swimming with Body and/or Caudal Fin (BCF). This review provides important guidance for the design of lEAP bionic robots.
基金supported by the National Basic Research Program of China(973 Program,2011CB935703,2010CB934700,2009CB930404 &2007CB936403)National Natural Science Foundation of China(20974113,20920102036)Center for Molecular Science,Chinese Academy of Sciences (CX-201014)
文摘In this review we have summarized some recent results mainly reported by our group that focused on the development of smart gating nanochannels based on polymer films. These nanochannels were prepared using a track-etch process. The responsive materials/molecules and modification methods/techniques have also been demonstrated, from which we have obtained a series of smart gating nanochannels that can respond to single/dual external stimuli, e.g., pH, ion, temperature, light, and so on. These studies utilize responsive behaviors to regulate ionic transport properties inside a single nanochannel and demonstrate the fea-sibility of designing other smart nanodevices in the future.