Constant divisions of rural land rights and contract renegotiations are the hallmark of China’s collective ownership system.Rural land ownership,property and operation systems in China have experienced four stages of...Constant divisions of rural land rights and contract renegotiations are the hallmark of China’s collective ownership system.Rural land ownership,property and operation systems in China have experienced four stages of evolution:(i)The People’s Communes,which served administrative and economic functions,exercised integrated collective land ownership,property,and operation rights.(ii)Under the system of“threetier ownership with production teams as basic accounting units,”production teams exercised the ownership right over land plots with greater autonomy and were responsible for organizing farm work.(iii)The household contract system has entitled farmers to claim surplus products and turned farm households into the basic unit of agricultural production.Subsequently,the reform of collective ownership has further enhanced farmers’contract rights and separated their operation rights from contract rights.The separation of rural land ownership,contract and operation rights marks a top-down design of the structure of China’s rural land rights after the collective ownership system and the reform of household contract system.By recognizing separate contract and operation rights without changing collective ownership,the separation aims to protect rural land contract and operation rights in accordance with the law.As in the four case studies,Chongzhou,Songjiang,Meitan and Liupanshui have experienced a restructuring of collective ownership,contract and operation rights.Their experience foretells complexities in the future evolution of rural land rights in China.展开更多
Quantum authorization management(QAM)is the quantum scheme for privilege management infrastructure(PMI)problem.Privilege management(authorization management)includes authentication and authorization.Authentication is ...Quantum authorization management(QAM)is the quantum scheme for privilege management infrastructure(PMI)problem.Privilege management(authorization management)includes authentication and authorization.Authentication is to verify a user’s identity.Authorization is the process of verifying that a authenticated user has the authority to perform a operation,which is more fine-grained.In most classical schemes,the authority management center(AMC)manages the resources permissions for all network nodes within the jurisdiction.However,the existence of AMC may be the weakest link of the whole scheme.In this paper,a protocol for QAM without AMC is proposed based on entanglement swapping.In this protocol,Bob(the owner of resources)authenticates the legality of Alice(the user)and then shares the right key for the resources with Alice.Compared with the other existed QAM protocols,this protocol not only implements authentication,but also authorizes the user permissions to access certain resources or carry out certain actions.The authority division is extended to fin-grained rights division.The security is analyzed from the four aspects:the outsider’s attack,the user’s attack,authentication and comparison with the other two QAM protocols.展开更多
文摘Constant divisions of rural land rights and contract renegotiations are the hallmark of China’s collective ownership system.Rural land ownership,property and operation systems in China have experienced four stages of evolution:(i)The People’s Communes,which served administrative and economic functions,exercised integrated collective land ownership,property,and operation rights.(ii)Under the system of“threetier ownership with production teams as basic accounting units,”production teams exercised the ownership right over land plots with greater autonomy and were responsible for organizing farm work.(iii)The household contract system has entitled farmers to claim surplus products and turned farm households into the basic unit of agricultural production.Subsequently,the reform of collective ownership has further enhanced farmers’contract rights and separated their operation rights from contract rights.The separation of rural land ownership,contract and operation rights marks a top-down design of the structure of China’s rural land rights after the collective ownership system and the reform of household contract system.By recognizing separate contract and operation rights without changing collective ownership,the separation aims to protect rural land contract and operation rights in accordance with the law.As in the four case studies,Chongzhou,Songjiang,Meitan and Liupanshui have experienced a restructuring of collective ownership,contract and operation rights.Their experience foretells complexities in the future evolution of rural land rights in China.
文摘Quantum authorization management(QAM)is the quantum scheme for privilege management infrastructure(PMI)problem.Privilege management(authorization management)includes authentication and authorization.Authentication is to verify a user’s identity.Authorization is the process of verifying that a authenticated user has the authority to perform a operation,which is more fine-grained.In most classical schemes,the authority management center(AMC)manages the resources permissions for all network nodes within the jurisdiction.However,the existence of AMC may be the weakest link of the whole scheme.In this paper,a protocol for QAM without AMC is proposed based on entanglement swapping.In this protocol,Bob(the owner of resources)authenticates the legality of Alice(the user)and then shares the right key for the resources with Alice.Compared with the other existed QAM protocols,this protocol not only implements authentication,but also authorizes the user permissions to access certain resources or carry out certain actions.The authority division is extended to fin-grained rights division.The security is analyzed from the four aspects:the outsider’s attack,the user’s attack,authentication and comparison with the other two QAM protocols.