共查询到18条相似文献,搜索用时 171 毫秒
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为提高制造网格环境下用户代理签名的安全性和性能,构建了一种密钥进化的基于身份的签名方案.在该方案中,使用前向安全来解决用户代理的私钥泄漏问题,并在随机Oracle模型下,基于计算Diffie-Hellman假设,形式化证明其安全性;引入基于身份密码学来改进效率,并基于完全二叉树构建,计算复杂度最多是总时间周期的对数;由用户代理自身来更新签名密钥,真正避免了网格用户必须经常在线;而且私钥更新具有前向安全性,当前的私钥泄漏,不会影响以前时间段签名的安全. 相似文献
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制造网格环境下项目的自组织协商与协调 总被引:4,自引:0,他引:4
针对制造项目的协商与协调,分别提出了制造网格的宏观控制结构与制造项目多层次资源配置原则。建立了项目代理与资源代理之间交互作用的一般框架,并嵌入博弈学习模型来控制代理双方的协商过程。基于同样的理由,对于制造项目的进程监控结构,也嵌入合作博弈的策略模型来加以控制。提出了基于包含Holonic过程模型的开放式Holonic制造系统体系结构,利用企业间互可操作性的统一企业建模语言,建立制造网格环境下多项目运行的仿真系统,用于评价前述的制造项目协商调度、运行协调结构和运行机制的实际效能。 相似文献
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基于椭圆曲线离散对数困难性假设和Gap Diffie—Hellman问题,提出了一个适用于制造网格环境下的基于身份的指定多接收者签密方案。新方案不仅能够在一个逻辑步骤内实现加密和认证,提高系统效率,而且能够实现一次签密,指定多个特定的接收者解签密并验证,为处在不同信任域的制造网格节点之间的交互认证提供了一种方法。最后基于这个特点,构造了一种适合于制造网格的高效的多信任域交互认证模型。 相似文献
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为提高制造网格环境下认证协议的安全性和性能,构建了标准模型下基于身份的认证协议.该协议紧密结合制造网格环境,可在托管模式、无托管模式和不同信任域模式下工作.通过引入伪随机函数集,新认证协议在标准模型下实现了显式双向认证,与其他标准模型下基于身份的认证协议比较,该协议的计算复杂度较低,适用于资源受限的制造网格环境.最后,基于困难性假设,在标准模型下证明了新认证协议的安全性. 相似文献
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《计算机集成制造系统》2014,(8)
为了满足虚拟企业资源在异构域间的安全有效共享,提出一个基于访问授权票据的跨异构域认证及密钥协商方案。利用基于公钥认证机制的分布式信任模型,在公钥基础设施域的认证中心证书授权与Kerberos域的认证服务器之间建立起第一级信任关系;在此基础上,由认证中心(或认证服务器联合票据授予服务器)生成并分发外域用户U访问本域资源S的授权票据,并通过设计基于对称密钥密码体制的双向跨域认证及密钥协商协议,建立U与S之间的第二级信任关系,协议的安全性通过SVO逻辑得到证明。分析表明,在满足各级安全需求的前提下,所提方法有效降低了终端计算量与通信量,可完全避免Kerberos域终端的公钥加解密运算,在虚拟企业跨异构域身份认证过程中具有良好的可实施性。 相似文献
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提出了一个基于可变权限集的广义虚拟企业信任交互方案,该方案能够根据虚拟企业的不同组织模式灵活设置成员权限集,并在成员结构发生变化时,对其进行动态调整.通过设计相应的虚拟认证中心来创建和颁发虚拟认证中心证书,在成员增减阶段变更参与方协议,有效解决了虚拟企业在各种组织模式下的信任交互问题.此外,该方案还实现了基于Pedersen可验证秘密共享技术的分布式密钥生成,既防止了密钥分发和更新过程中成员的不诚实行为,又克服了盟主单独行使密钥分发权利所带来的安全隐患.分析表明,该方案不但安全性大大增强,而且能够更好地适应虚拟企业复杂多变的动态环境. 相似文献
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在公钥基础设施(PKI)体制的安全认证系统中,签发服务器使用一对密钥中的私钥对所签发的证书进行签名,保证此证书的不可伪造性,通常采用专用加密机进行根密钥的生成、使用,密钥对存放于加密机中不可导出,因此加密机的加密性能将影响签发服务器签发证书的性能.设计了一种对签发服务器加密机加密性能进行测试的方案,采用此方案对某型号专用加密机进行了实际测试,得出了可供整个安全认证系统设计、参考的实用数据. 相似文献
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以ANSYS为平台的塔式起重机臂架有限元分析与关键技术研究 总被引:1,自引:0,他引:1
为了解决在传统设计方法下塔式起重机试制样机成本高、设计效率低等弊端,应用CAE软件ANSYS对QTZ40型塔式起重机的臂架进行建模与有限元分析,通过对臂架的强度校核和各阶模态的计算,验证了该型塔式起重机设计方案的合理性,也证实了有限元分析法的可行性.总结了建模时的等效简化处理以及约束、载荷施加等关键技术的经验,从而为塔式起重机产品的设计、生产和制造提供理论依据. 相似文献
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John P. Shewchuk Colin L. Moodie 《International Journal of Flexible Manufacturing Systems》1998,10(4):325-349
Flexibility is one of the most sought-after properties in modern manufacturing systems. Despite this interest, flexibility remains poorly understood in theory and poorly utilized in practice. One reason for this is the lack of general agreement on how to define flexibility: over 70 terms (types and measures) can be found in the literature. This paper concerns developing a framework and classification scheme for use in defining and classifying the various terms regarding flexibility found in manufacturing. The framework consists of six attributes: level of manufacturing requirements specification, manufacturing system specification, manufacturing environment specification, flexibility dimension, flexibility measurement approach, and time frame. A six-field hybrid classification scheme is developed based on this framework. The framework serves as a guide for developing new flexibility terms, whereas the classification scheme provides a mechanism for summarizing the important aspects of and assumptions behind a given term. The approach is demonstrated by using the classification scheme to classify over 50 existing flexibility terms. The results indicate that the classification scheme is an effective tool to aid in understanding different flexibility terms and how they compare to one another. At the same time, the difficulty of the classification exercise indicates the need for a suitable framework when defining such terms. 相似文献
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调度网格及其关键技术研究 总被引:1,自引:0,他引:1
针对网络化制造的需求,提出了调度网格的概念;建立了调度网格的层次化体系结构,将其划分为应用层、中间件层、接口与协议层、资源层和网络层共5层。基于Multi-Agent技术,对调度网格中的若干个关键技术包括制造资源、全局过程分析、任务调度、服务平台等问题进行了较深入分析;并指出了调度网格应用中急需解决的技术问题。 相似文献
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Dong Tang Udatta S. Palekar 《The International Journal of Advanced Manufacturing Technology》2010,51(5-8):561-573
This paper deals with the planning problem in a nanodeposition manufacturing process, in which a toolbit that consists of a multilayer grid of micro/nanofluidic channels is used to deposit nanoscale liquid materials to desired positions on workparts to form solid patterns. The objective is to obtain a planning procedure that achieves efficient throughput for the studied nanodeposition manufacturing systems. We break down the studied problem into several sub-problems as design pattern decomposition, nanopore assignment, liquid material routing in the multilayer grid fluidic network, and toolbit path planning. Efficient algorithms are proposed to solve these sub-problems individually, and then finally integrated into a framework that systematically plans the nanodeposition manufacturing process. A software tool that plans, simulates, and controls the nanodeposition manufacturing process by implementing the proposed algorithms is reported in this paper. 相似文献
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Hesuan Hu Zhiwu Li 《The International Journal of Advanced Manufacturing Technology》2009,42(5-6):553-568
A manufacturing grid workflow can be viewed as the composition of activities that execute on heterogeneous, distributed, and job-dependent resources in a virtual organization to accomplish a specific manufacturing goal. Scheduling emerges as a key issue in manufacturing grid workflows since it assigns manufacturing resources to perform the required activities such that the optimal service is obtained. However, scheduling problems prove to be NP-hard due to the inherent combination explosion vices adhered to discrete event systems, such as the grid manufacturing. To crack such a hard nut, we focus on the formulation of a heuristic search algorithm based on timed Petri nets. When the activities involved in the manufacturing grid workflow can be executed by more than one resource, this scheduling algorithm selects the optimal one so as to minimize the makespan. Furthermore, the proposed scheduling policy in this paper aims to be dynamic rather than static such that the whole algorithm can be applied in a dynamic manufacturing grid environment. Both the theoretical and experimental results validate the legitimacy of the proposed approach. 相似文献
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Fei Tao Ye Fa Hu Zu De Zhou 《The International Journal of Advanced Manufacturing Technology》2008,37(9-10):1022-1041