In this paper, we introduce and study the generalized frame in a separableHilbert space H. Using operator-theoretic-methods, we give some conditions for a gen-eralized frame to be a tight frame, a dual frame, or an in...In this paper, we introduce and study the generalized frame in a separableHilbert space H. Using operator-theoretic-methods, we give some conditions for a gen-eralized frame to be a tight frame, a dual frame, or an independent frame in H. We alsoprove some results concerning generalized frame operators.展开更多
Sustainable Livelihood Security(SLS)remains a rarely considered yet important issue for rural sustainability and natural resource management.Particularly in China,rural SLS research in a typical area is urgently neede...Sustainable Livelihood Security(SLS)remains a rarely considered yet important issue for rural sustainability and natural resource management.Particularly in China,rural SLS research in a typical area is urgently needed,but insufficient under the background of National Rural Revitalization and Ten-year Fishing Ban of Yangtze River.Focusing on the policy-targeted inland lake area,we proposed a Livelihood Security Analysis(LSA)framework by establishing an adaptive indicator system and integrating multiple econometrical and geographical methods.This study aims to evaluate the SLS in Poyang Lake Eco-economic Zone comprehensively from the three aspects of ecology,economy and society,analyze their spatial patterns,identify the main constraints,and finally give specific suggestions for improving rural sustainability management.The results showed that rural SLS in the inland great lake area tended to be vulnerable mainly due to the lagging economic efficiency and unbalanced social equality,and mediated by regional ecological characteristics.The overall SLS and Ecological Security Index(ESI)were higher in the north and lower in the south,while Economic Efficiency Index(EEI)and Social Equality Index(SEI)were at the middle level and circularly distributed around Nanchang City.The dominating factors which have greatly shaped the spatial pattern of SLS include rural per capita electricity consumption,fishery breeding area,population dependency ratio,urbanization rate,and fishery population.The obstacle degree is ranked as economic system>social system>ecological system.An outdated economy and incomplete social services are the main constraints,characterized by weak electricity consumption,limited beds in hospitals,low urbanization rate,deficient agricultural machinery power,and a small agricultural output value.Therefore,one urgent need is to activate the rural economy by reinforcing rural electric power facilities and promoting agricultural mechanization.In addition,transforming the peasants/fishermen to the non-agricultural sector should be accelerated,which will help to reduce ecological pressure,boost urban-rural integration and narrow the income gap.展开更多
Due to the coexistence and coupling of continuous variables and discrete events, the vehicle height adjustment process of electronic air suspension system can be regarded as a typical hybrid system. Therefore, the hyb...Due to the coexistence and coupling of continuous variables and discrete events, the vehicle height adjustment process of electronic air suspension system can be regarded as a typical hybrid system. Therefore, the hybrid system theory was applied to design a novel vehicle height control strategy in this paper. A nonlinear mechanism model of the vehicle height adjustment system was established based on vehicle system dynamics and thermodynamic theory for variable-mass gas charge/discharge system. In order to model both the continuous/discrete dynamics of vehicle height adjustment process and the on-off statuses switching of solenoid valves, the framework of mixed logical dynamical(MLD) modelling was used. On the basis of the vehicle height adjustment control strategy, the MLD model of the adjustment process was built by introducing auxiliary logical variables and auxiliary continuous variables. Then, the co-simulation of the nonlinear mechanism model and the MLD model was conducted based on the compiling of HYSDEL. The simulation and experimental results show that the proposed control strategy can not only adjust the vehicle height effectively, but also achieve the on-off statuses direct control of solenoid valves.展开更多
基金Supported by National Natural Science Foundation of China (19971056)
文摘In this paper, we introduce and study the generalized frame in a separableHilbert space H. Using operator-theoretic-methods, we give some conditions for a gen-eralized frame to be a tight frame, a dual frame, or an independent frame in H. We alsoprove some results concerning generalized frame operators.
基金The National Natural Science Foundation of China(41861036)The China Postdoctoral Science Foundation(2018M630738)+5 种基金The NaturalScience Foundation of Jiangxi Province(20192BAB213023)The Young Doctor Fund of Jiangxi Social Science Plan(17BJ38)The Humanitiesand Social Sciences Research Project of Jiangxi Universities(GL18238)The Postdoctoral Daily Fund of Jiangxi Province in 2018(2018RC29)The Jiangxi Provincial Postdoctoral Science Foundation(2019KY11)The Science and Technology Project of Education Department of Jiangxi Province(GJJ200504).
文摘Sustainable Livelihood Security(SLS)remains a rarely considered yet important issue for rural sustainability and natural resource management.Particularly in China,rural SLS research in a typical area is urgently needed,but insufficient under the background of National Rural Revitalization and Ten-year Fishing Ban of Yangtze River.Focusing on the policy-targeted inland lake area,we proposed a Livelihood Security Analysis(LSA)framework by establishing an adaptive indicator system and integrating multiple econometrical and geographical methods.This study aims to evaluate the SLS in Poyang Lake Eco-economic Zone comprehensively from the three aspects of ecology,economy and society,analyze their spatial patterns,identify the main constraints,and finally give specific suggestions for improving rural sustainability management.The results showed that rural SLS in the inland great lake area tended to be vulnerable mainly due to the lagging economic efficiency and unbalanced social equality,and mediated by regional ecological characteristics.The overall SLS and Ecological Security Index(ESI)were higher in the north and lower in the south,while Economic Efficiency Index(EEI)and Social Equality Index(SEI)were at the middle level and circularly distributed around Nanchang City.The dominating factors which have greatly shaped the spatial pattern of SLS include rural per capita electricity consumption,fishery breeding area,population dependency ratio,urbanization rate,and fishery population.The obstacle degree is ranked as economic system>social system>ecological system.An outdated economy and incomplete social services are the main constraints,characterized by weak electricity consumption,limited beds in hospitals,low urbanization rate,deficient agricultural machinery power,and a small agricultural output value.Therefore,one urgent need is to activate the rural economy by reinforcing rural electric power facilities and promoting agricultural mechanization.In addition,transforming the peasants/fishermen to the non-agricultural sector should be accelerated,which will help to reduce ecological pressure,boost urban-rural integration and narrow the income gap.
基金supported by the National Natural Science Foundation of China(Grant Nos.51375212 and 51105177)the Specialized Research Fund for the Doctoral Program of Higher Education of China(Grant No.20133227130001)the China Postdoctoral Science Foundation(Grant No.2014M551518)
文摘Due to the coexistence and coupling of continuous variables and discrete events, the vehicle height adjustment process of electronic air suspension system can be regarded as a typical hybrid system. Therefore, the hybrid system theory was applied to design a novel vehicle height control strategy in this paper. A nonlinear mechanism model of the vehicle height adjustment system was established based on vehicle system dynamics and thermodynamic theory for variable-mass gas charge/discharge system. In order to model both the continuous/discrete dynamics of vehicle height adjustment process and the on-off statuses switching of solenoid valves, the framework of mixed logical dynamical(MLD) modelling was used. On the basis of the vehicle height adjustment control strategy, the MLD model of the adjustment process was built by introducing auxiliary logical variables and auxiliary continuous variables. Then, the co-simulation of the nonlinear mechanism model and the MLD model was conducted based on the compiling of HYSDEL. The simulation and experimental results show that the proposed control strategy can not only adjust the vehicle height effectively, but also achieve the on-off statuses direct control of solenoid valves.
