基于粒度的访问控制冲突分析及解决办法

访问控制规范了安全域中合法用户访问与操作资源的行为,保证资源不被非授权用户使用,从而起到保护资源的作用。访问控制粒度指明系统为用户授权的层次,如目录级授权与文件级授权等。当不同粒度安全域的用户进行资源互访时,则易造成访问权限的缩放以及授权的冲突等问题。分析不同粒度访问控制的特点,指出冲突产生的原因。同时,提出跨域资源访问应遵守的规则。根据这些原则,给出因访问控制粒度而引起的冲突解决方法。     

角色访问控制在分布式环境下的一种实现

介绍自主访问控制、强制访问控制和角色访问控制三种主流的访问控制策略,并对这三种访问控制策略进行了比较.在基于角色的访问控制模型中引入域的概念,使基于角色的访问控制模型更加适合分布式访问控制的特点.     

基于稀疏索引和哈希表的访问控制策略检索方法

在云计算场景下想要实现细粒度的访问控制需要设置大量的访问控制策略,针对策略条目大量增加导致的策略检索效率低下的情况,提出了一种基于稀疏索引和哈希表的访问控制策略检索方法,通过策略表生成的哈希缓存表,稀疏索引哈希表,稠密索引表构建了一个多级检索体系,从而缩减策略的检索范围,提高策略的检索效率.实验结果表明:相较于现有的检索方法,基于稀疏索引和哈希表的访问控制策略检索方法具有更高的检索效率.     

舰船信息共享服务平台的安全策略

舰船信息共享服务平台中存在大量机密信息,一旦泄露,将造成不可估量的后果。为此,针对当前基于任务、属性以及角色的安全访问策略漏洞问题,提出一种新的舰船信息共享服务平台的安全策略。该策略结合信任值理论,利用网络爬虫技术获取用户行为数据,通过计算用户行为信任值判断用户是否可信,从而以此为基础判断用户是否可以访问平台。结果表明,与上述3种传统安全访问策略相比,所提安全策略控制下,非法成功访问率只有0.2%,因此能更为精准的对非法访问进行阻拦,保证了信息共享服务平台中信息的安全。     

一种改进的信任链模型

基于BIBA模型,对TCG规范中信任链传递过程中的完整性进行了分析,指出信任链传递写入过程中存在的完整性问题,提出了一种改进的信任链传递模型,实现了系统上电到系统装载过程可信校验和访问控制的方法,有效阻止了恶意代码植入和运行.     

船舶信息无线传输网络的用户访问安全性算法研究

对船舶信息无线传输网络进行访问控制是实现船舶信息安全保护的重要手段,但是随着权限管理复杂程度的增长和用户量的增加,基于角色的用户访问安全性算法安全性不足,不能有效控制非法用户的访问请求。针对上述问题,提出基于信任值的用户访问安全性算法。首先计算用户与船舶信息无线传输网络之间的直接信任值;然后通过二者之间的直接信任值获得用户间接信任值;最后在直接信任值和间接信任值的基础上,求得用户的综合信任值,评估用户的信任等级,实现对船舶信息无线传输网络的安全访问。结果表明:与基于角色的用户访问安全性算法相比,基于信任值的用户访问安全性算法的成功访问率降低了13%,表明前者的安全性要好于后者,能有效控制非法用户的访问请求。     

基于Agent的信息融合系统研究与设计

传感器资源分配是传感器管理中的核心问题,在未来海上战争的网络中心战的背景下,对如何完成多种传感器之间有效协同作战,使资源能够合理分配到各个传感器,具有十分重要的意义.论文介绍了一种基于Agent的信息融合系统结构,对该系统中各传感器Agent的协商机制进行了研究,并重点研究了基于合同网协议的分布式分配策略,最后用Repast仿真软件对其进行了仿真,证明了该方法的有效性与实用性.     

档案信息资源开发与单位知识产权保护

随着我国社会经济的不断发展以及档案信息资源开发与利用的不断深入,利用法律保护这些创造性的结晶成果(如某单位开发的高新技术产品、专利、专著等),将成为我国现代社会得以迅速发展的关键。在信息化时代的推动下,受单位知识产权保护的档案信息资源开发将面临严峻威胁。本文通过简要介绍目前档案信息资源开发与单位知识产权保护的状况及两者间的联系,对档案信息资源开发对实施单位知识产权保护的影响进行了详细分析,提出相应完善的策略来加强档案信息资源开发中的单位知识产权保护。     

云存储环境下的船舶航行数据访问控制方法

对船舶航行数据进行访问控制是实现数据机密性和进行隐私保护的重要手段,但是由于用户对数据密钥的获取权限完全由数据属主控制,权限管理的复杂程度将随数据量和用户量的增长显著提高,影响数据访问控制效果。针对上述问题,提出一种新型船舶航行数据访问控制方法——AB-ACCS。AB-ACCS对数据访问的安全性进行假定,并以此为出发点进行AB-ACCS基本设计,在设计过程中对访问用户的身份进行测定,授予或取消用户的访问能力,如果用户身份合理,则对用户读写数据过程进行再次控制,保证数据的安全性。控制方法设计完成后,对其进行实验分析,结果表明:AB-ACCS方法显著降低了数据访问控制的复杂性。     

基于PMI的Web安全访问控制系统设计

针对Web资源得安全控制问题,设计了一个基于授权管理基础设施PMI技术的安全访问控制系统。系统依据匿名证书对用户进行身份认证,使用属性证书为用户授予角色,通过角色访问策略控制对Web资源的访问。该系统对Web资源的安全访问控制提供了一种有效的解决方案。     

全流通下的财务报告与信息披露

我国资本市场股权分置改革基本完成。这就要求上市公司在全流通后的财务报告及信息披露将更为完善。本文分析了目前我国上市公司的财务报告及信息披露存在的问题,对规范上市公司会计信息披露提出了对策:上市公司不仅需要提供公司的财务信息,而且需要提供公司治理、内部控制、风险控制、社会责任等相关情况,并从企业内部监管、法律监管、社会监管等方面规范上市公司的会计信息披露。     

基于ADRMS的数字内容权限管理

数字内容的受控访问管理正在成为用户业务正常进行的重要条件。文章研究了基于Windows AD RMS服务的信息授权保护的原理,阐述了信息受控发布和访问的过程,部署了一个AD RMS演示网络,并在这个演示网络上进行了信息授权服务的试验。AD RMS可以用来构建功能完善且强大的信息权限保护系统。     

A Participatory Approach to Marine Habitat Mapping in the Grenadine Islands

Increasing interest in implementing an ecosystem-based management approach has made stakeholder involvement vital and has highlighted the need for an effective participatory framework. In this study we used a participatory geographic information systems (PGIS) framework to collaboratively map the marine resources of the transboundary Grenadine Islands with a broad range of stakeholders from the two sovereign nations. We found the application of PGIS allowed the collective resolution of an appropriate mapping scale and a locally relevant habitat classification scheme that would not only serve the needs of resource managers, but could also be understood by resource users. Furthermore, multi-level stakeholder involvement in the mapping process captured resource use profiles and other fishing-related attributes, gave credibility to local knowledge and ownership of information, and was instrumental in building capacity to access and use the produced information. Lessons learned included the importance of investing considerable time early in the participatory process, which was later rewarded by stakeholder buy-in and led to financial and in-kind support. Furthermore, hosting the information in multiple formats on a project website has resulted in easy access and use by a wide range of stakeholders over a cross-country scale. We believe our experiences will be valuable to other practitioners considering using PGIS, particularly for those working in similar resource-limited, developing nation contexts.     

实时操作系统信号量机制的设计与实现

信号量是用来控制共享资源互斥访问和线程同步通信的协议机制，它是操作系统中的重要部分。基于广泛使用的高性能数字信号处理器ADSP—TS201，从线程创建、调度策略和信号量操作这三个方面，设计并实现实时操作系统中的信号量机制，为下一步开发完整的实时操作系统奠定了基础。     

On a clear day in Ogunquit,Maine

Abstract

Winning a court case against a federal agency may seem to be the sweetest success for an environmental group, but losing litigation is not total failure. In the case of Ogunquit Village Corporation et al., vs. R. M. Davis the plaintiff lost the legal skirmish against the Soil Conservation Service, but in doing so significantly aided the struggle within the agency to implement more environmentally sensitive planning and engineering procedures. This paper describes the court case in terms of the Soil Conservation Service's procedural and policy responses including the agency's modus operandi and the internal paths/pitfalls involved with the implementation of visual resource management. The author also speculates as to the visual resource understanding of the evidence presented by the plaintiff and a possible but unstated visual basis for the original complaint.     

政府投资项目代建制下的信息沟通与披露机制

政府投资项目实施的各个阶段中,不同参与方之间的信息沟通可能存在信息不充分、信息不对称、信息不准确以及信息成本高的问题。这不仅会增加项目实施的成本,而且可能使项目实施与既定目标发生偏差,并可能给某些主体违法牟利以可乘之机。为抑制这些信息失灵问题,文章分析了代建项目各阶段的信息沟通关系及存在的信息失灵,探讨了解决信息失灵问题的措施,最后归纳出了代建制下的十类信息沟通与披露机制。     

Spatially Prioritizing Seafloor Mapping for Coastal and Marine Planning

Coastal and marine areas provide vital services to support the economic, cultural, recreational, and ecological needs of human communities, but sustaining these benefits necessitates a balance between growing and often competing uses and activities. Minimizing coastal zone conflict and reducing human-induced impacts to ecological resources requires access to consistent spatial information on the distribution and condition of marine resources. Seafloor mapping provides a detailed and reliable spatial template on the structure of the seafloor that has become a core data need for many resource management strategies. The absence of detailed maps of the seafloor hinders the effectiveness of priority setting in marine policy, regulatory processes, and marine stewardship. For large management areas, the relatively high cost of seafloor mapping and limited management budgets requires careful spatial prioritization. In order to address this problem, a consensus based approach, aided by decision-support tools, and participatory geographic information systems (GIS), was implemented in Long Island Sound to spatially prioritize locations, define additional data collection efforts needed, and identify products needed to inform decision-making. The methodology developed has utility for other states and regions in need of spatially prioritizing activities for coastal planning, and organizations charged with providing geospatial services to communities with broad informational needs.     

Exploring Participants' Views of Participatory Coastal and Marine Resource Management Processes

It is generally accepted that stakeholders, including resource users, scientists, conservationists, government and nongovernment organizations, and the general public, can contribute positively to management processes and may even benefit from such processes. However, we continue to struggle with how to design processes that effectively involve these stakeholders. To illuminate potential improvements to traditional processes, this study examines participants’ perceptions of coastal and marine resource management processes. Through semi-structured interviews, respondents describe how they feel about various elements of participatory processes. Responses offer insight into the multiple dimensions of participatory process elements described in the literature, such as influence on decisions, exchange of information, access to the process, transparent decision making, and others. Responses also identify additional elements that have received limited attention in the public-participation literature: hosting meetings at various scales, recognizing differences within interest groups, and considering the context of a process. Results from this study will help to inform the design of participatory coastal and marine resource management processes.     

基于B/S架构态势原型系统实现及性能优化

C/S（客户机-服务器）模式软件存在客户端资源消耗大、部署繁杂、升级困难等问题。论文设计了一种基于Java平台的B/S（浏览器-服务器）架构态势原型系统,解决了体系结构、信息规范、网络通信及态势显示等关键技术,实现了实时目标信息接入、图上显示及综合查询等功能。论文还讨论了Java平台性能优化技术,优化后的原型系统运行结果良好,在指挥控制系统领域具有应用价值。