This paper theoretically analyzes a deficiency of the existing scheme, and proposes a distributed multi-hop certification authority scheme for mobile Ad Hoc networks. In our design, we distribute the certification aut...This paper theoretically analyzes a deficiency of the existing scheme, and proposes a distributed multi-hop certification authority scheme for mobile Ad Hoc networks. In our design, we distribute the certification authority functions through a threshold secret sharing mechanism, in which each node holds a secret share and multiple nodes jointly provide complete services. Certification authority is not limited in a local neighborhood but can be completed within multi-hop location. In addition, we replace broadcast by multicast to improve system performance and reduce communication overhead. This paper resolves some technical problems of ubiquitous certification authority services, and presents a wieldy multi-hop certification authority algorithm. Simulation results confirm the availability and effectiveness of our design.展开更多
Distributed certification via threshold cryptography is much more secu re than other ways to protect certification authority (CA) 's private key,and c an tolerate some intrusions. As the original system such as IT...Distributed certification via threshold cryptography is much more secu re than other ways to protect certification authority (CA) 's private key,and c an tolerate some intrusions. As the original system such as ITTC,etc.,is unsaf e ,inefficient and impracitcal in actual network environment,this paper brings u p a new distributed certification scheme,which although it generates key shares concentratively,it updates key shares distributedly,and so,avoids single-po in t failure like ITTC. It not only enhances robustness with Feldman verification and SSL protocol,but can also change the threshold (t,k) flexibly and robu stly,and so,is much more practical. In this work,the authors implement the prototype sy stem of the new scheme and test and analyze its performance.展开更多
随着分布式新能源和电动汽车等虚拟储能的广泛接入,电力系统的不确定性和低惯量特性变得更加显著,系统的频率运行风险增加,并且主动配电网内部的供需关系呈现出更加灵活多样的特征,导致其与输电网之间的功率交互关系也更加复杂。为此,...随着分布式新能源和电动汽车等虚拟储能的广泛接入,电力系统的不确定性和低惯量特性变得更加显著,系统的频率运行风险增加,并且主动配电网内部的供需关系呈现出更加灵活多样的特征,导致其与输电网之间的功率交互关系也更加复杂。为此,构建了一种基于主动配电网灵活性支撑机制的电-碳-绿证分布式协同优化方法,以充分挖掘输配系统中分布式资源的支撑能力及其碳减排效益。首先,建立了与输配协同系统匹配的动态频率安全约束和基于双向调节模型的主动配电网灵活性支撑机制,提出了输配系统间的电-碳-绿证协同交互框架。为应对新能源出力的不确定性,将两侧子系统中涉及不确定变量的约束建模为联合机会约束。采用交替方向乘子法(alternating direction of multipliers algorithm,ADMM)进行输配系统的分布式协同。仿真结果表明,所提模型能够有效挖掘配电网中分布式资源的支撑潜力,灵活体现主动配电网的向外支撑能力或被支撑需求。与传统方法相比,系统动态频率安全性和输配协同调节灵活性显著提升,总运行成本较输电网单独调度模型降低13.42%,新能源减载量较忽略多市场耦合模型减少16.76%,系统运行经济性和低碳性明显改善。此外,所提出的求解方法比基于传统的样本平均近似方法减少约98%的计算时间,能够实现输配系统的快速分布式协同优化。展开更多
Considering the secure authentication problem for equipment support information network,a clustering method based on the business information flow is proposed. Based on the proposed method,a cluster-based distributed ...Considering the secure authentication problem for equipment support information network,a clustering method based on the business information flow is proposed. Based on the proposed method,a cluster-based distributed authentication mechanism and an optimal design method for distributed certificate authority( CA)are designed. Compared with some conventional clustering methods for network,the proposed clustering method considers the business information flow of the network and the task of the network nodes,which can decrease the communication spending between the clusters and improve the network efficiency effectively. The identity authentication protocols between the nodes in the same cluster and in different clusters are designed. From the perspective of the security of network and the availability of distributed authentication service,the definition of the secure service success rate of distributed CA is given and it is taken as the aim of the optimal design for distributed CA. The efficiency of providing the distributed certificate service successfully by the distributed CA is taken as the constraint condition of the optimal design for distributed CA. The determination method for the optimal value of the threshold is investigated. The proposed method can provide references for the optimal design for distributed CA.展开更多
TrustedRBAC is a scalable, decentralized trust-management and access control mechanism for systems that span multiple autonomous domains. We utilize X.509 attri- bute certificates to define trust domains, roles to def...TrustedRBAC is a scalable, decentralized trust-management and access control mechanism for systems that span multiple autonomous domains. We utilize X.509 attri- bute certificates to define trust domains, roles to define controlled activities, and role delegation across domains to represent permissions to these activities. This paper describes the TrustedRBAC model and its scalable design and implementation.展开更多
To meet the authorization administration requirements in a distributedcomputer network environment, this paper extends the role-based access control model with multipleapplication dimensions and establishes a new acce...To meet the authorization administration requirements in a distributedcomputer network environment, this paper extends the role-based access control model with multipleapplication dimensions and establishes a new access control model ED-RBAC(Extended Role Based AccessControl Model) for the distributed environment. We propose an extendable hierarchical authorizationassignment framework and design effective role-registeringi role-applying and role-assigningprotocol with symmetric and asymmetric cryptographic systems. The model can be used to simplifyauthorization administration in a distributed environment with multiple applications.展开更多
Scene graph is a infrastructure of the virtual reality system to organize the virtual scene with abstraction, it can provide facility for the rendering engine and should be integrated effectively on demand into a real...Scene graph is a infrastructure of the virtual reality system to organize the virtual scene with abstraction, it can provide facility for the rendering engine and should be integrated effectively on demand into a real-time system, where a large quantities of scene objects and resources can be manipulated and managed with high flexibility and reliability. We present a new scheme of multiple scene graphs to accommodate the features of rendering engine and distributed systems. Based upon that, some other functions, e.g. block query, interactive editing, permission management, instance response, ＂redo＂ and ＂undo＂, are implemented to satisfy various requirements. At the same time, our design has compatibility to popular C/S architecture with good concurrent performance. Above all, it is convenient to be used for further development. The results of experiments including responding time demonstrate its good performance.展开更多
为提高低碳园区综合能源系统(regional integrated energy system,RIES)的低碳性和可再生能源消纳率,提出一种考虑电转气(power-to-gas,P2G)、碳捕集装置(carbon capture and storage,CCS)和氢燃料电池(hydrogen fuel cell,HFC)协调运行...为提高低碳园区综合能源系统(regional integrated energy system,RIES)的低碳性和可再生能源消纳率,提出一种考虑电转气(power-to-gas,P2G)、碳捕集装置(carbon capture and storage,CCS)和氢燃料电池(hydrogen fuel cell,HFC)协调运行的RIES低碳经济调度方法。首先,根据传统火电机组集中碳排放的特点,加入CCS打造更具灵活性的碳捕集电厂(carbon capture power plant,CCPP)。其次,在两阶段P2G中加入HFC,细化氢能使用,建立P2G-CCS-HFC整体模型,在氢能平衡约束条件下,分析不同设备决策对整体模型优化成本的影响。同时,在供能侧和需求侧分别引入绿证-碳交易和综合需求响应双重市场机制激励。最后,考虑风光不确定性,以风光历史数据为基础,构建考虑场景分析和数据驱动的、以最小化总成本为目标函数的RIES分布鲁棒调度模型。基于算例的仿真结果表明,该方法可有效降低碳排放水平,促进新能源消纳,为区域综合能源系统低碳经济调度等研究提供参考。展开更多
文摘This paper theoretically analyzes a deficiency of the existing scheme, and proposes a distributed multi-hop certification authority scheme for mobile Ad Hoc networks. In our design, we distribute the certification authority functions through a threshold secret sharing mechanism, in which each node holds a secret share and multiple nodes jointly provide complete services. Certification authority is not limited in a local neighborhood but can be completed within multi-hop location. In addition, we replace broadcast by multicast to improve system performance and reduce communication overhead. This paper resolves some technical problems of ubiquitous certification authority services, and presents a wieldy multi-hop certification authority algorithm. Simulation results confirm the availability and effectiveness of our design.
文摘Distributed certification via threshold cryptography is much more secu re than other ways to protect certification authority (CA) 's private key,and c an tolerate some intrusions. As the original system such as ITTC,etc.,is unsaf e ,inefficient and impracitcal in actual network environment,this paper brings u p a new distributed certification scheme,which although it generates key shares concentratively,it updates key shares distributedly,and so,avoids single-po in t failure like ITTC. It not only enhances robustness with Feldman verification and SSL protocol,but can also change the threshold (t,k) flexibly and robu stly,and so,is much more practical. In this work,the authors implement the prototype sy stem of the new scheme and test and analyze its performance.
文摘随着分布式新能源和电动汽车等虚拟储能的广泛接入,电力系统的不确定性和低惯量特性变得更加显著,系统的频率运行风险增加,并且主动配电网内部的供需关系呈现出更加灵活多样的特征,导致其与输电网之间的功率交互关系也更加复杂。为此,构建了一种基于主动配电网灵活性支撑机制的电-碳-绿证分布式协同优化方法,以充分挖掘输配系统中分布式资源的支撑能力及其碳减排效益。首先,建立了与输配协同系统匹配的动态频率安全约束和基于双向调节模型的主动配电网灵活性支撑机制,提出了输配系统间的电-碳-绿证协同交互框架。为应对新能源出力的不确定性,将两侧子系统中涉及不确定变量的约束建模为联合机会约束。采用交替方向乘子法(alternating direction of multipliers algorithm,ADMM)进行输配系统的分布式协同。仿真结果表明,所提模型能够有效挖掘配电网中分布式资源的支撑潜力,灵活体现主动配电网的向外支撑能力或被支撑需求。与传统方法相比,系统动态频率安全性和输配协同调节灵活性显著提升,总运行成本较输电网单独调度模型降低13.42%,新能源减载量较忽略多市场耦合模型减少16.76%,系统运行经济性和低碳性明显改善。此外,所提出的求解方法比基于传统的样本平均近似方法减少约98%的计算时间,能够实现输配系统的快速分布式协同优化。
基金National Natural Science Foundation of China(No.61271152)Natural Science Foundation of Hebei Province,China(No.F2012506008)the Original Innovation Foundation of Ordnance Engineering College,China(No.YSCX0903)
文摘Considering the secure authentication problem for equipment support information network,a clustering method based on the business information flow is proposed. Based on the proposed method,a cluster-based distributed authentication mechanism and an optimal design method for distributed certificate authority( CA)are designed. Compared with some conventional clustering methods for network,the proposed clustering method considers the business information flow of the network and the task of the network nodes,which can decrease the communication spending between the clusters and improve the network efficiency effectively. The identity authentication protocols between the nodes in the same cluster and in different clusters are designed. From the perspective of the security of network and the availability of distributed authentication service,the definition of the secure service success rate of distributed CA is given and it is taken as the aim of the optimal design for distributed CA. The efficiency of providing the distributed certificate service successfully by the distributed CA is taken as the constraint condition of the optimal design for distributed CA. The determination method for the optimal value of the threshold is investigated. The proposed method can provide references for the optimal design for distributed CA.
文摘TrustedRBAC is a scalable, decentralized trust-management and access control mechanism for systems that span multiple autonomous domains. We utilize X.509 attri- bute certificates to define trust domains, roles to define controlled activities, and role delegation across domains to represent permissions to these activities. This paper describes the TrustedRBAC model and its scalable design and implementation.
文摘To meet the authorization administration requirements in a distributedcomputer network environment, this paper extends the role-based access control model with multipleapplication dimensions and establishes a new access control model ED-RBAC(Extended Role Based AccessControl Model) for the distributed environment. We propose an extendable hierarchical authorizationassignment framework and design effective role-registeringi role-applying and role-assigningprotocol with symmetric and asymmetric cryptographic systems. The model can be used to simplifyauthorization administration in a distributed environment with multiple applications.
基金Supported by National Natural Science Foundation of China(Nos.61173080,61232014,61472010,61421062)National Key Technology Support Program of China(No.2013BAK03B07)
文摘Scene graph is a infrastructure of the virtual reality system to organize the virtual scene with abstraction, it can provide facility for the rendering engine and should be integrated effectively on demand into a real-time system, where a large quantities of scene objects and resources can be manipulated and managed with high flexibility and reliability. We present a new scheme of multiple scene graphs to accommodate the features of rendering engine and distributed systems. Based upon that, some other functions, e.g. block query, interactive editing, permission management, instance response, ＂redo＂ and ＂undo＂, are implemented to satisfy various requirements. At the same time, our design has compatibility to popular C/S architecture with good concurrent performance. Above all, it is convenient to be used for further development. The results of experiments including responding time demonstrate its good performance.
文摘为提高低碳园区综合能源系统(regional integrated energy system,RIES)的低碳性和可再生能源消纳率,提出一种考虑电转气(power-to-gas,P2G)、碳捕集装置(carbon capture and storage,CCS)和氢燃料电池(hydrogen fuel cell,HFC)协调运行的RIES低碳经济调度方法。首先,根据传统火电机组集中碳排放的特点,加入CCS打造更具灵活性的碳捕集电厂(carbon capture power plant,CCPP)。其次,在两阶段P2G中加入HFC,细化氢能使用,建立P2G-CCS-HFC整体模型,在氢能平衡约束条件下,分析不同设备决策对整体模型优化成本的影响。同时,在供能侧和需求侧分别引入绿证-碳交易和综合需求响应双重市场机制激励。最后,考虑风光不确定性,以风光历史数据为基础,构建考虑场景分析和数据驱动的、以最小化总成本为目标函数的RIES分布鲁棒调度模型。基于算例的仿真结果表明,该方法可有效降低碳排放水平,促进新能源消纳,为区域综合能源系统低碳经济调度等研究提供参考。
