基于ATP-ABE的访问控制方案

对访问控制机制中存在的安全性和有效性的问题进行了研究，提出了基于访问树剪枝的属性加密ATP-ABE（Access Tree Pruning Attribute Based Encryption）的访问控制方案。当ATP-ABE算法需要访问它的树型结构访问策略时，通过剪枝处理访问树结构中包含用户ID属性节点的分支，提高了用户所有者DO（Data Owner）管理和控制属性的效率，更加有效地实现了数据共享。还为访问树结构设计了许可访问属性，使DO仍保留共享数据的关键属性，并且能够完全控制它们的共享数据。基于决策双线性密钥交换算法DBDH（Decisional Bilinear Diffie-Hellman）假设分析了ATP-ABE方案的安全性，研究结果表明与两种经典ABE方案比较，ATP-ABE更加有效地减少了算法的系统设置、私钥生成、密文大小、用户属性撤销以及加解密过程中的计算开销，并给出了定量结论。     

An improved attribute reduction scheme with covering based rough sets

Attribute reduction is viewed as an important preprocessing step for pattern recognition and data mining. Most of researches are focused on attribute reduction by using rough sets. Recently, Tsang et al. discussed attribute reduction with covering rough sets in the paper (Tsang et al., 2008), where an approach based on discernibility matrix was presented to compute all attribute reducts. In this paper, we provide a new method for constructing simpler discernibility matrix with covering based rough sets, and improve some characterizations of attribute reduction provided by Tsang et al. It is proved that the improved discernibility matrix is equivalent to the old one, but the computational complexity of discernibility matrix is relatively reduced. Then we further study attribute reduction in decision tables based on a different strategy of identifying objects. Finally, the proposed reduction method is compared with some existing feature selection methods by numerical experiments and the experimental results show that the proposed reduction method is efficient and effective.     

廊坊市地籍信息系统的建立

介绍了廊坊市地籍信息系统的建立过程及系统的功能、组成、运行环境等，并就系统中地籍模型的建立、查询统计功能的实现等问题进行了讨论。     

高程点与高程注记的匹配及其应用

在基于AutoCAD的地形图中,提出解决高程点与高程注记匹配方法,并利用高程注记作为高程点的属性的方法实现高程点与高程注记的组合,以及在高程处理中的一些应用.     

粗集数据挖掘技术在市场营销中的应用

基于粗糙集理论的启发式数据挖掘算法,先量化数据属性的重要性,再对属性排序,并对选择的属性子集进行约简条件判定.在选择若干次后获得满足约简条件的属性子集.利用该算法,通过预处理、数据约减等步骤从商场营销数据库中收集顾客属性数据,消去多余数据属性.并由此预测需求趋势,评估需求倾向的改变,以便进行决策.     

当代城市空间的符号价值

随着中国发达地区城市由生产社会向消费社会的转型,空间呈现商品化的发展态势,空间符号价值的重要性也日益突显出来。一方面,城市空间所象征的个性和品位、身份和地位、生活方式等符号意义逐渐成为大众空间消费过程中所关注的重点;另一方面,空间符号的消费强化了空间的社会属性,并为城市带来新的发展契机。     

Further investigations into the reproducibility of check-all-that-apply (CATA) questions for sensory product characterization elicited by consumers

The purpose of the present research was further investigate the reproducibility of check-all-that-apply (CATA) questions for sensory product characterization. Evaluations obtained when such questions are used by consumers are rarely replicated and therefore reproducibility of the data may be at risk. Results from the present work, which included five studies, each with 100–200 consumers across a range of product categories, revealed that sensory product characterizations obtained using CATA questions with consumers are highly reproducible. Hence, the research confirms previous research by Jaeger, Chheang, et al. (2013) and extends it to the use of CATA terms in randomised presentation order as has been recommended to avoid satisficing response behavior. In the future, if CATA studies are conducted without replication and researches seek to examine the reliability of CATA data, the use of a posterior bootstrapping re-sampling approach is suggested.     

Estimation of the Parameters of the Gamma Distribution by Sample Quantiles

This paper deals with large sample estimation of the location parameter (α₁ and the scale parameter α₂ in the gamma distribution with known shape parameter. Best linear unbiased estimates based on k sample quantiles are used. For a given k, the optimum spacings of the sample quantiles can be replaced by simpler “nearly optimum” spacings at virtually no loss of asymptotic efficiency. The theory behind the nearly optimum spacings is briefly reviewed. The major part of the paper concerns estimation of α₂ when α₂ is known. Nearly optimum spacings together with the coefficients to be used in computing the estimates are presented in a number of tables for k = 1(1) 10, and various values of the shape parameter. The paper also contains brief discussions of estimation of α₁, when α₂ is known, and simultaneous estimation of α₁ and α₂.     

利用.Net4.0的特性实现AOP的方法研究

AOP技术为开发者提供了一种描述横切关注点的机制,现介绍了一种在.Net开发环境下利用.Net4.0的新特性实现的方法拦截,从而实现AOP技术的设计方案,同时给出了动态织入和静态织入.