为进一步提高RBAC(Role Based Access Control)数据库的安全性,提出构建以角色为基础的误用检测模型.通过对审计日志的形式化定义来实现对原始审计数据的预处理,利用对记录项的支持率、距离值等参数的聚类来生成轮廓文件的方法,并由轮...为进一步提高RBAC(Role Based Access Control)数据库的安全性,提出构建以角色为基础的误用检测模型.通过对审计日志的形式化定义来实现对原始审计数据的预处理,利用对记录项的支持率、距离值等参数的聚类来生成轮廓文件的方法,并由轮廓文件给出了该模型的安全审计规则.研究表明:以角色为基础的误用检测模型可以有效地控制来自数据库内部人员的滥用职权.展开更多
Integrated profile is one of the basic characteristic of X-ray pulsar. Gaussian function fit is used to model the components of X-ray pulsar profile, and it is combined with Poisson distribution model of X-ray pulsar ...Integrated profile is one of the basic characteristic of X-ray pulsar. Gaussian function fit is used to model the components of X-ray pulsar profile, and it is combined with Poisson distribution model of X-ray pulsar to analyze Cramer-Rao low bound （CRLB） of phase, phase rate estimation and relation between CRLB and profile components. Then, a time domain method using minimum entropy is proposed for profile phase and phase rate estimation, and its effectiveness is explained using simulation examples.展开更多
文摘为进一步提高RBAC(Role Based Access Control)数据库的安全性,提出构建以角色为基础的误用检测模型.通过对审计日志的形式化定义来实现对原始审计数据的预处理,利用对记录项的支持率、距离值等参数的聚类来生成轮廓文件的方法,并由轮廓文件给出了该模型的安全审计规则.研究表明:以角色为基础的误用检测模型可以有效地控制来自数据库内部人员的滥用职权.
基金supported by the National Hi-Tech Research and Development Program of China ("863" Project) (Grant No. 2007AA12Z323)the National Natural Science Foundation of China (Grant No. 60772139)
文摘Integrated profile is one of the basic characteristic of X-ray pulsar. Gaussian function fit is used to model the components of X-ray pulsar profile, and it is combined with Poisson distribution model of X-ray pulsar to analyze Cramer-Rao low bound （CRLB） of phase, phase rate estimation and relation between CRLB and profile components. Then, a time domain method using minimum entropy is proposed for profile phase and phase rate estimation, and its effectiveness is explained using simulation examples.
