The study of mathematical models on information retrieval is an important area in the Information Retrievalcommunity. Because of the uncertainty characteristic of IR,the probability model based on statistical probabil...The study of mathematical models on information retrieval is an important area in the Information Retrievalcommunity. Because of the uncertainty characteristic of IR,the probability model based on statistical probability is apromising model from recent to future. Those models can be classified into classical models and probability networkmodels. Several famous models are introduced and their shortcomings are pointed out in this paper. We also clarifythe relationship of these models and introduce a new models based on statistical language model curtly.展开更多
围绕外包数据的安全性问题与用户隐私性问题,展开对加密数据库方案的研究,提出了一个面向多用户的多层嵌套数据库加密方案.该方案根据洋葱模型多层理论,采用多种不同类型的加密算法对用户的外包数据进行多层嵌套加密,实现了既保证数据...围绕外包数据的安全性问题与用户隐私性问题,展开对加密数据库方案的研究,提出了一个面向多用户的多层嵌套数据库加密方案.该方案根据洋葱模型多层理论,采用多种不同类型的加密算法对用户的外包数据进行多层嵌套加密,实现了既保证数据机密性又满足多种不同SQL查询类型的数据库加密方案.针对用户递交包含敏感信息的查询语句在一定程度上泄露用户自身的隐私这一问题,设计了基于单服务器私有信息检索(private information retrieval,PIR)技术的用户隐私保护机制,实现了用户匿名查询.安全性分析表明,该方案满足数据机密性与用户隐私性. Sysbench基准测试实验分析表明,该方案具有良好的查询处理效率、读写吞吐量以及健壮性.展开更多
文摘The study of mathematical models on information retrieval is an important area in the Information Retrievalcommunity. Because of the uncertainty characteristic of IR,the probability model based on statistical probability is apromising model from recent to future. Those models can be classified into classical models and probability networkmodels. Several famous models are introduced and their shortcomings are pointed out in this paper. We also clarifythe relationship of these models and introduce a new models based on statistical language model curtly.
文摘围绕外包数据的安全性问题与用户隐私性问题,展开对加密数据库方案的研究,提出了一个面向多用户的多层嵌套数据库加密方案.该方案根据洋葱模型多层理论,采用多种不同类型的加密算法对用户的外包数据进行多层嵌套加密,实现了既保证数据机密性又满足多种不同SQL查询类型的数据库加密方案.针对用户递交包含敏感信息的查询语句在一定程度上泄露用户自身的隐私这一问题,设计了基于单服务器私有信息检索(private information retrieval,PIR)技术的用户隐私保护机制,实现了用户匿名查询.安全性分析表明,该方案满足数据机密性与用户隐私性. Sysbench基准测试实验分析表明,该方案具有良好的查询处理效率、读写吞吐量以及健壮性.
