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基于角色的访问权限控制在电力MIS中的应用 总被引:2,自引:0,他引:2
本文在研究RBAC访问控制模型的基础上,设计了一种应用于电力MIS系统的RBAC模型.在该模型的设计工程中,详细讨论了安全控制中的资源对象、权限划分与角色定义,并引入了组织结构、业务流程和子任务等概念对RABC基本模型进行扩展.根据电力企业的组织结构,建立了电力MIS软件的权限划分方法,并设计了访问控制数据库的结构.通过调用存储过程对安全信息库进行操作,实现了系统资源的安全访问,并完成了基于RBAC的管理软件的设计. 相似文献
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广域测量系统WAMS(Wide Area Measurement System)是新一代智能电网的重要组成部分,访问控制对于维护WAMS的系统安全十分重要。针对传统RBAC模型在复杂业务权限控制中的不足及WAMS中设备的特点,引入了被访问对象类型的属性和权限约束模块,对传统的RBAC模型进行改进。该模型使WAMS的访问控制更加灵活,角色管理更加方便。 相似文献
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基于角色的访问控制(RBAC)是目前研究得最多、思想最成熟的一种面向企业安全需求的访问控制策略。文中在核心RBAC基本模型的基础上,将角色集和权限集进行细分。细分后的核心RBAC在权限设置上更加细致,每一级管理员可以按照实际需要,对角色的功能、权限从数据周期、数据对象、数据类别、操作功能、操作级别5个维度上进行明细设置,并灵活、深入地控制角色的功能及其访问的数据内容,从而达到精确管理的目的。将细粒度化的RBAC模型应用于供电企业资源计划(ERP)系统的权限管理模块的开发中,并取得了良好的应用效果。 相似文献
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电力信息系统中基于属性的访问控制模型的设计 总被引:1,自引:0,他引:1
电力信息系统构成一个复杂的多域环境,它为电力行业进行信息交换和协作带来便捷的同时,也带来了极大的安全隐患。由于多域环境下存在多种应用系统,且用户数目众多、来源广泛,给传统的基于角色访问控制(RBAC)模型带来了用户 — 角色赋值工作量大、多域间映射困难等问题。文中针对多域环境设计了一种基于属性的访问控制模型,属性是在角色的基础上扩展得来的,并提出利用元属性和元策略分别对域内的属性和策略进行描述,充分满足电力信息系统所处的异构环境和所有者对资源进行自主管理的需求,保证了域内、域外用户对系统资源进行访问的安全。 相似文献
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文中提出在电力企业资源计划ERP系统中引入RBAC模型,将角色作为用户和权限的中间体,为用户指派不同的角色,对每个角色分配权限,降低用户直接对权限操作的风险.利用最小授权和角色继承概念,根据业务职责对角色分级划分,实现对系统资源的安全存取,使权限管理变得简单而高效,节省了系统维护的开销. 相似文献
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为了提高电力营销系统用户访问控制效果,提出基于RBAC模型的电力营销系统用户权限分配方法。利用信任度属性扩展访问策略表达式,通过监控用户的访问行为,获得电力营销系统信息资源的全局信任度,控制访问权限;根据访问权限控制结果,在分析自主型访问控制模型和强制型访问控制模型的基础上,基于RBAC模型,引入角色的概念,通过量化计算用户中不同的访问行为在分配权限时彼此的信任度,获取用户权限访问等级,完成电力营销系统用户权限分配。实验结果表明,所提方法的电力营销系统用户访问权限控制时间较短,用户权限分配误差率较低,提高了用户满意程度。 相似文献
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ABSTRACT The paper addresses the design of a power system, stabilizer using an optimal reduced order model whose state variables are torque angles and speeds. System damping can be improved using eigenvalue assignment, and the coordination of stabilizers can be achieved through eigenvector assignment by maintaining system mode shape. The proportional-integral PSS is derived via the optimal reduced order model instead of via the whole system model. The effectiveness of this stabilizer is evaluated, and this study reveals that the result of eigenstructure assignment is more stable and much better than in the assignment method based on the whole system model. A one-machine infinite-bus system and a multimachine system are given as examples to illustrate the advantages and effectiveness of the proposed approach. Results based on the whole system model are included for comparison. 相似文献
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Power system stabilizer (PSS) design is addressed using an optimal reduced order model whose state variables are torque angles and speeds. System damping can be improved by using eigenvalue assignment, and the coordination of stabilizers can be achieved through eigenvector assignment by maintaining system mode shapes. The proportional-integral PSSs are derived by the optimal reduced order model. The effectiveness of the stabilizer is evaluated. By using the output feedback only, the result of eigenstructure assignment is more stable and much better than the assignment method based on the whole system model. Examples, a single-machine to infinite bus system and a multimachine system, are given to illustrate the advantages and effectiveness of the proposed approach. Results based on the whole system model are included for comparative analyses 相似文献
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Liga Xia J. B. Moore M. Gevers 《International Journal of Adaptive Control and Signal Processing》1987,1(2):143-160
In this paper a first step is taken to avoid ill-conditioning in adaptive estimation and pole assignment schemes for the case when there is a signal model overparametrization. Such a situation can occur in practice when an unknown model order is guessed too high so as to be on the ‘safe’ side. The methods proposed in the paper are relatively simple compared with on-line order determination, being based on introducing suitable excitation in the ‘regression’ vectors of the parameter estimation algorithms to ensure parameter convergence. For the case when the models are non-unique in that pole-zero cancellations can occur, the algorithms seek to estimate the unique model where the cancellations occur at the origin. Applying estimates of this (unique) model turns out to avoid ill-conditioning in central tendency adaptive pole assignment. For the case of one pole-zero cancellation the convergence theory of the algorithm is complete. For the more general case algorithms are readily devised which appear to work well but for which a complete theory is not available. 相似文献
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直流电场计算校核是换流变压器设计的重要环节。研究表明直流电压下油纸界面电荷积聚分布与传统阻容模型计算结果之间存在很大差异,基于理想模型的电场校核方法失效。该文提出一种基于油纸界面电荷特性、直接在换流变压器实际结构中进行电荷分段赋值的外推方法。首先,对于均匀场区域,用离子迁移模型计算出各个油纸界面的电荷密度,进行均一化赋值。其次,对于非均匀场区域,从均匀场区域向非均匀场区域推算,根据具体赋值部位的界面电荷分布曲线,划分区间并分段赋值。最后,将电荷场与外施电场叠加合成,获得全域内直流电场分布情况。在换流变压器阀侧出线结构模型中的实测验证表明,电荷分段映射叠加外推方法得到的电场计算值与电场实测值之间偏差较小。该方法解决了传统方法依赖材料宏观参数、无法准确计算和反映大尺寸油纸绝缘系统电场分布真实情况的问题。 相似文献
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M. G. Persova Yu. G. Soloveichik Z. S. Temlyakova M. V. Abramov D. V. Vagin M. V. Gamadin 《Russian Electrical Engineering》2011,82(6):292-297
The method of modeling three-dimensional magnetic fields in electrotechnical devices based on extracting the two-dimensional
part of the field is described in the present paper. Two techniques for extracting the field depending on the type of the
device and the approaches to both realization of computer model assignment for the electrotechnical device and automatic control
of the process of building finite element mashes are described. 相似文献
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基于CARMA模型的自校正预测PID调节器的应用 总被引:1,自引:0,他引:1
本文分析了用于离散控制系统常规PID调节器的两种典型算法,提出了基于CARMA模型自校正极点配置预测PID调节器新结构。并在电阻加热炉温度控制系统中获得了成功应用。取得了令人满意的控制效果。 相似文献
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