保护私有信息的范围搜索算法

合作计算的任务可能发生在彼此互不完全信任的各方之间,此时各方参与运算只是想知道最终的结果,而不希望自己的隐私信息被别人获取.安全多方计算所要解决的正是合作计算的隐私保护问题,它能够在保证各方输入的隐私数据安全性的同时获得正确的计算结果.本文考虑学术界一直悬而未决的保护私有信息的范围搜索问题,并且基于安全多方计算的理论和方法实现两类范围搜索协议,同时对它们的安全性、时间复杂性和通讯复杂性进行详细的分析讨论.在本文最后,我们将范围搜索协议应用到保护私有信息的DBSCAN算法中.     

保护私有信息的两多边形相交面积计算

保护私有信息的计算几何是一类特殊的安全多方计算问题,在军事、商业等领域具有重要的应用前景。在半诚实模型下,利用点线叉积协议设计一个保护私有信息的点包含于多边形判定协议;基于该协议,提出保护私有信息的两多边形相交面积计算协议;分析和证明上述协议的正确性、安全性和复杂性。     

基于Skyline计算的社交网络关系数据隐私保护

随着社交软件的流行，越来越多的人加入社交网络产生了大量有价值的信息，其中也包含了许多敏感隐私信息。不同的用户有不同的隐私需求，因此需要不同级别的隐私保护。社交网络中用户隐私泄露等级受社交网络图结构和用户自身威胁等级等诸多因素的影响。针对社交网络数据的个性化隐私保护问题及用户隐私泄露等级评价问题，提出基于Skyline计算的个性化差分隐私保护策略（PDPS）用以发布社交网络关系数据。首先构建用户的属性向量；接着采用基于Skyline计算的方法评定用户的隐私泄露等级，并根据该等级对用户数据集进行分割；然后应用采样机制来实现个性化差分隐私，并对整合后的数据添加噪声；最后对处理后数据进行安全性和实用性的分析并发布数据。在真实数据集上与传统的个性化差分隐私方法（PDP）对比，验证了PDPS算法的隐私保护质量和数据的可用性都优于PDP算法。     

H-PCPIR-V：基于Huffman编码的PCPIR-V优化算法

隐私问题受到越来越多的关注,基于计算的私有信息检索(CPIR)的隐私保护技术允许用户从服务提供商检索数据并且不会泄露查询信息。但是,对于大规模应用,隐私保护技术与可用性之间存在较大差距。针对CPIR算法计算量大、计算时间长而不适合应用于大规模数据隐私保护的问题,提出了基于Spark和Huffman编码的CPIR最近邻查询隐私保护算法(H-PCPIR-V)。H-PCPIR-V算法主要是在数据预处理阶段将最近邻矩阵使用Huffman编码进行压缩减少计算位数,然后通过压缩后矩阵中元素的最大位数对其他元素进行补位,在服务端使用Spark并行框架对查询网格进行并行计算。通过对比实验及实验结果分析发现,相比PCPIR-V算法,H-PCPIR-V算法在服务端的计算代价下降30%左右,客户端的计算代价下降10%左右,通信代价下降40%左右。     

Graham算法求解凸包问题中的隐私保护

凸包问题是构造其他几何形体的有效工具。保护私有信息的凸包求解问题是一个特殊的安全多方计算问题。基于安全多方计算的基础协议,设计了一个保护私有信息的凸包求解协议,解决了基于隐私保护的凸包求解问题,并讨论和分析了其安全性和正确性。     

一种新的在线社交网络的隐私保护方案

针对用户数据隐私容易被截取的问题,提出了一种新的用户在线社交网络隐私保护方案.传统解决方案依赖于公共密钥基础设施或传统密钥分布技术,而新的方案则充分利用朋友和用户的私有属性熵之间的信任.通过重新构建密码模块建立安全协议,对在线社交网络提供安全信息服务、安全信息匹配和安全通信三种服务,最终使用户能够安全地存储自己的私有数据,并建立一个会话密钥的安全通信.     

一个点与矩形区域包含关系的安全判定协议

点与矩形区域包含关系的安全判定是指两个用户基于各自的输入信息,共同完成矩形区域是否包含点的判定,并且双方都不能获得对方的输入信息,该问题是一个安全两方计算问题,广泛应用于竟标、拍卖等不泄露信息的商业领域.通过对点与矩形区域位置关系的分析,得到一个判定点与矩形区域位置的公式,然后基于点积协议设计了一个点与矩形区域包含关系的安全判定协议,并且分析了协议的正确性、安全性和复杂性.在保护用户私有输入信息的条件下,解决了点与矩形区域的位置关系判定问题.     

隐私保护的四方判定线段是否相交协议

鉴于目前已有的隐私保护的线段相交判定协议的参与方都是两方,不能解决多方之间判定线段是否相交的问题,因此提出了一个隐私保护的四方相互合作判定线段是否相交的协议.4个参与方各自拥有线段的一个端点,采用安全多方计算中的一些基础运算协议,通过两两计算,判定由这4个端点构成的两条线段是否相交,同时确保不会向其它的参与方泄漏线段以及端点的信息.最后给出了该协议在现实中的一个应用.     

空间几何对象相对位置判定中的私有信息保护

保护私有信息的计算几何是一类特殊的安全多方计算问题，它是指在一个互不信任的多用户网络中，几个用户基于各自输入的几何信息共同协作来完成某项可靠的计算任务，但任何一个用户都不愿意向其他用户暴露自己的输入，该问题在协作进行太空开发等领域有着重要的应用前案．秘密判定两组数据是否对应成比例是安全多方计算的一个基本问题，在判定空间几何对象相对位置关系中起着重要作用．设计了判断两组数据是否对应成比例的秘密判定协议；分析了该协议的正确性、安全性及复杂性；在保护用户私有输入信息的条件下，解决了空间中点、直线、平面等几何对象之间的相对位置判定问题．     

普适计算认证过程基于粗糙集的隐私保护策略

在普适计算环境中,用户要获得需要的服务,需要向对应的服务提供商提供一定的认证信息,而这些认证信息中往往包含有用户不希望泄漏的隐私信息。为了对这些隐私信息进行保护,本文提出了认证过程中基于粗糙集的隐私保护策略：用户将认证信息扩展成粗糙集提供给服务提供商;服务提供商根据策略从粗糙集中提取用户的真实认证信息对用户请求进行认证。该策略充分利用了粗糙集合的不确定性,能够有效地防止用户隐私泄漏。     

Only connect: teaching, technology and telesis

Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.     

European Community policy and the market

Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.     

一种自适应子融合集成多分类器方法

融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。     

Avoiding semantic and temporal gaps in developing software intensive systems

Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.     

Designing economic np control charts: A programmed simulation approach

This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.     

The development of robot art

Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008     

Explanation and prediction: an architecture for default and abductive reasoning

Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.     

Three Process Perspectives: Organizations, Teams, and People

This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)^SM and Team Software Process (TSP){^SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.     

基于复小波噪声方差显著修正的SAR图像去噪

提出了一种基于复小波域统计建模与噪声方差估计显著性修正相结合的合成孔径雷达(Synthetic Aperture Radar,SAR)图像斑点噪声滤波方法。该方法首先通过对数变换将乘性噪声模型转化为加性噪声模型,然后对变换后的图像进行双树复小波变换(Dualtree Complex Wavelet Transform,DCWT),并对复数小波系数的统计分布进行建模。在此先验分布的基础上,通过运用贝叶斯估计方法从含噪系数中恢复原始系数,达到滤除噪声的目的。实验结果表明该方法在去除噪声的同时保留了图像的细节信息,取得了很好的降噪效果。     

基于QTE的蒙古文显示机制研究与实现

蒙古语言是中国蒙古族使用的通用语言,由于蒙古文区别于其他文字的书写方式和其自身变形机制等特点,在很多通用的文字处理引擎中都不被支持。在嵌入式产品开发与应用领域中Linux加QTE已经成为流行方式。该文给出了一种在QTE环境上实现基于标准Unicode的蒙古文点阵显示和变形算法, 并自定义了支持蒙古文的QTE组件,扩展了QTE功能,为在Linux加QTE方式的嵌入式体系结构中处理蒙古文提供了一种解决方法。