Trusted path is one of the crucial features that operating systems must provide for fundamental security support. In order to explore the possibility of implementing a trusted path mechanism with the support of truste...Trusted path is one of the crucial features that operating systems must provide for fundamental security support. In order to explore the possibility of implementing a trusted path mechanism with the support of trusted platform module （TPM） technologies, and to support TPM capabilities in operating systems, the paper extended the scope of the conventional trusted path to cover the situation in which a user communicates with software residing on a remote host. The paper combined the concept of operating system support for trusted path with that for TPM platforms, and proposed the architecture of an extended trusted path mechanism in operating system with considerations on TPM-capable platforms support. As part of the author＇s research in secure operating systems, the work of the paper was carried out with Linux as an experimental prototype system. The research result shows that TPM capabilities can strengthen extended trusted path mechanisms of operating systems.展开更多
In this paper, we combine the nonmonotone and adaptive techniques with trust region method for unconstrained minimization problems. We set a new ratio of the actual descent and predicted descent. Then, instead of the ...In this paper, we combine the nonmonotone and adaptive techniques with trust region method for unconstrained minimization problems. We set a new ratio of the actual descent and predicted descent. Then, instead of the monotone sequence, the nonmonotone sequence of function values are employed. With the adaptive technique, the radius of trust region △k can be adjusted automatically to improve the efficiency of trust region methods. By means of the Bunch-Parlett factorization, we construct a method with indefinite dogleg path for solving the trust region subproblem which can handle the indefinite approximate Hessian Bk. The convergence properties of the algorithm are established. Finally, detailed numerical results are reported to show that our algorithm is efficient.展开更多
Software systems in distributed environment are changing from a close and relatively static form, whose users are familiar with each other, to an open and highly dynamic mode, which can be visited by public. In such c...Software systems in distributed environment are changing from a close and relatively static form, whose users are familiar with each other, to an open and highly dynamic mode, which can be visited by public. In such circumstance, trust evaluation model becomes focus of intense research at current time. Trust evaluation model establishes a management framework of trust relationship between entities, involving expression and measurement of trust, comprehensive calculation of direct trust value and recommended trust value, and recognition of malicious entities and recommendations. Based on the analysis of several typical trust evaluation models, the classification of trust evaluation ideas and modes is discussed, the questions existing in current research and the directions of future research are pointed out.展开更多
为了弥补AODV(Ad Hoc on Demand Distance Vector)路由协议安全方面的缺点,同时获取基于该优化协议下的最短路径,文中采用信任机制模型方法,在原始AODV路由协议上改进TAODV(Trusted Ad Hoc on Demand Distance Vector Routing Algorithm...为了弥补AODV(Ad Hoc on Demand Distance Vector)路由协议安全方面的缺点,同时获取基于该优化协议下的最短路径,文中采用信任机制模型方法,在原始AODV路由协议上改进TAODV(Trusted Ad Hoc on Demand Distance Vector Routing Algorithm)路由协议。该协议以各个节点的信任值为基础进行相关运算,从而判断在路由协议运作过程中的路径信任值。通过在MATLAB平台中对相关参数进行设置,对改进后的TAODV协议进行模拟。仿真结果表明,改进后的TAODV路由协议在归一化路由开销、最小跳数和最优路径方面均优于传统的AODV路由协议,同时增强了网络的鲁棒性和抗毁性。展开更多
针对社交网络中协同过滤推荐算法的推荐速度计算问题,提出了一种基于最近邻方法的改进计算方法,并对算法有效性进行了分析。该算法对用户的相似性度量采用基于最短路径的信任关系,用分层图和动态规划的方法进行计算,并在社交网络的应用...针对社交网络中协同过滤推荐算法的推荐速度计算问题,提出了一种基于最近邻方法的改进计算方法,并对算法有效性进行了分析。该算法对用户的相似性度量采用基于最短路径的信任关系,用分层图和动态规划的方法进行计算,并在社交网络的应用中对关系链的深度进行限制。对该算法基于KDD Cup 2012 Track 1的数据进行了仿真,并与其他方法做了性能比较。实验表明,改进算法可以很好地平衡推荐效率和准确率指标。展开更多
基金Supported by the National Natural Science Foun-dation of China (60373054)
文摘Trusted path is one of the crucial features that operating systems must provide for fundamental security support. In order to explore the possibility of implementing a trusted path mechanism with the support of trusted platform module （TPM） technologies, and to support TPM capabilities in operating systems, the paper extended the scope of the conventional trusted path to cover the situation in which a user communicates with software residing on a remote host. The paper combined the concept of operating system support for trusted path with that for TPM platforms, and proposed the architecture of an extended trusted path mechanism in operating system with considerations on TPM-capable platforms support. As part of the author＇s research in secure operating systems, the work of the paper was carried out with Linux as an experimental prototype system. The research result shows that TPM capabilities can strengthen extended trusted path mechanisms of operating systems.
基金Supported by the NNSF(10231060 and 10501024)of Chinathe Specialized Research Fund(20040319003)of Doctoral Program of Higher Education of China+1 种基金the Natural Science Grant(BK2006214)of Jiangsu Province of Chinathe Foundation(2004NXY20)of Nanjing Xiaozhuang College.
文摘In this paper, we combine the nonmonotone and adaptive techniques with trust region method for unconstrained minimization problems. We set a new ratio of the actual descent and predicted descent. Then, instead of the monotone sequence, the nonmonotone sequence of function values are employed. With the adaptive technique, the radius of trust region △k can be adjusted automatically to improve the efficiency of trust region methods. By means of the Bunch-Parlett factorization, we construct a method with indefinite dogleg path for solving the trust region subproblem which can handle the indefinite approximate Hessian Bk. The convergence properties of the algorithm are established. Finally, detailed numerical results are reported to show that our algorithm is efficient.
基金the National Natural Science Foundation of China (60503020, 60503033, 60703086)the Natural Science Foundation of Jiangsu Province(BK2006094)+2 种基金the Opening Foundation of Jiangsu Key Labo-ratory of Computer Information Processing Technology in Soochow Univer-sity(KJS0714)the Research Foundation of Nanjing University of Posts and Telecommunications (NY207052,NY207082, NY207084)Microsoft Re-search Asia Internet Services Theme 2008
文摘Software systems in distributed environment are changing from a close and relatively static form, whose users are familiar with each other, to an open and highly dynamic mode, which can be visited by public. In such circumstance, trust evaluation model becomes focus of intense research at current time. Trust evaluation model establishes a management framework of trust relationship between entities, involving expression and measurement of trust, comprehensive calculation of direct trust value and recommended trust value, and recognition of malicious entities and recommendations. Based on the analysis of several typical trust evaluation models, the classification of trust evaluation ideas and modes is discussed, the questions existing in current research and the directions of future research are pointed out.
文摘为了弥补AODV(Ad Hoc on Demand Distance Vector)路由协议安全方面的缺点,同时获取基于该优化协议下的最短路径,文中采用信任机制模型方法,在原始AODV路由协议上改进TAODV(Trusted Ad Hoc on Demand Distance Vector Routing Algorithm)路由协议。该协议以各个节点的信任值为基础进行相关运算,从而判断在路由协议运作过程中的路径信任值。通过在MATLAB平台中对相关参数进行设置,对改进后的TAODV协议进行模拟。仿真结果表明,改进后的TAODV路由协议在归一化路由开销、最小跳数和最优路径方面均优于传统的AODV路由协议,同时增强了网络的鲁棒性和抗毁性。
文摘针对社交网络中协同过滤推荐算法的推荐速度计算问题,提出了一种基于最近邻方法的改进计算方法,并对算法有效性进行了分析。该算法对用户的相似性度量采用基于最短路径的信任关系,用分层图和动态规划的方法进行计算,并在社交网络的应用中对关系链的深度进行限制。对该算法基于KDD Cup 2012 Track 1的数据进行了仿真,并与其他方法做了性能比较。实验表明,改进算法可以很好地平衡推荐效率和准确率指标。
