一种新的社会化相似度计算方法

基于社交网络的推荐算法引入社交网络信息到协同过滤算法中来, 使得用户朋友的偏好能够影响用户本身的偏好 。这些算法需要用到用户之间的相似度信息。目前有两个流行的基于共同评分项目集的相似度计算函数（VSS、PCC）。在很多情况下, 由于用户间没有共同评分项目集, 故无法计算他们之间的相似度。为了解决这个问题, 提出了一种基于矩阵分解的新的社会化相似度计算方法。在真实的包含社交网络的数据集上进行实验验证, 该方法的性能优于几个经典的基于社交网络的协同过滤算法, 而且能够解决新用户的冷启动问题。     

一种新的社会化相似度计算方法

基于社交网络的推荐算法引入社交网络信息到协同过滤算法中来,使得用户朋友的偏好能够影响用户本身的偏好。这些算法需要用到用户之间的相似度信息。目前有两个流行的基于共同评分项目集的相似度计算函数(VSS、PCC)。在很多情况下,由于用户间没有共同评分项目集,故无法计算他们之间的相似度。为了解决这个问题,提出了一种基于矩阵分解的新的社会化相似度计算方法。在真实的包含社交网络的数据集上进行实验验证,该方法的性能优于几个经典的基于社交网络的协同过滤算法,而且能够解决新用户的冷启动问题。     

一种基于耦合对象相似度的项目推荐算法

推荐系统根据用户的偏好为用户推荐个性化的信息、产品和服务等,能够帮助用户有效解决信息过载问题。基于内容的协同过滤算法缺少合适的度量指标用来计算项目之间的相似度。提出一种基于耦合对象相似度的项目推荐算法,即通过耦合对象相似度捕获项目特征频率分布相似性和特征依赖聚合相似度。首先从项目文本中抽取项目的关键特征,然后利用耦合对象相似度构建项目相似度模型,最后使用协同过滤的方法为活动用户推荐用户可能感兴趣的项目。在真实数据集上的实验结果表明,基于耦合对象相似度的推荐算法可以有效解决基于内容推荐系统的项目相似度度量问题,在缺失大量项目特征数据的情况下改进传统基于内容推荐系统的推荐质量。     

基于社交关系的可信群体推荐

针对当前群体推荐技术只单独考虑用户-项目评分,而没有较好考虑相关上下文信息的问题,提出基于社交关系的可信群体推荐。该方法在相似度计算中考虑群体特性,首先通过两种方式计算单个用户与目标群体之间的可信度,一种是基于距离的社交可信因子,另外一种是基于影响力的社交可信因子;然后将可信因子用于群体与单个用户之间的相似度计算中,使得在后续的群体邻居选取中融入可信度的考虑,从而提升群体邻居的质量,进一步提升推荐的准确度。基于真实数据的仿真实验表明,两种可信度计算方法与已有方法相比在准确性和准确率方面表现更好。     

基于用户兴趣和社交信任的聚类推荐算法

个性化推荐系统中使用最广泛的算法是协同过滤算法,针对该算法存在的数据稀疏和扩展性差问题,提出了一种基于用户兴趣和社交信任的聚类推荐算法。该算法首先基于聚类技术根据用户评分信息将具有相同兴趣的用户聚为一类,并建立基于用户兴趣相近的邻居集合。为了提高兴趣相似度计算的准确性,采用了修正余弦计算公式来消除评分标准的差异问题。然后,引入信任机制,通过定义直接信任、间接信任、传递路径和计算方法来度量社交网络用户之间隐含的信任值,将社交网络转换为信任网络,依据信任程度来创建基于社交信任的邻居集合。通过加权的方式将基于两种邻居集合的预测值融合起来为用户产生项目的推荐。在Douban数据集上进行仿真实验,确定了最优的协调因子值和分类数值,并与基于用户的协同过滤算法和基于信任的推荐算法进行对比,实验结果表明,所提算法的平均绝对误差(MAE)减少了6.7%,准确率(precision)、覆盖(recall)和F1值分别增加了25%、40%和37%,有效提高了推荐系统的推荐质量。     

融合本体语义与用户属性的协同过滤算法

传统协同过滤推荐算法在处理海量数据时存在数据稀疏性和项目长尾效应,导致推荐精度较低。针对该问题,结合本体语义和用户属性,提出一种改进的协同过滤算法。利用本体计算项目之间的语义相似度,构建项目相似度矩阵,同时引入用户属性计算用户相似度矩阵。通过融合本体语义和用户属性形成用户-项目评分矩阵,并对该矩阵的预测评分进行加权处理,生成TOP-N推荐结果。实验结果表明,相比传统皮尔逊相似度计算协同过滤算法、基于本体语义的协同过滤算法和基于评分矩阵填充与用户兴趣的协同过滤算法,该算法的平均绝对误差较低,准确率较高,综合性能及新颖度较优。     

基于事件本体的新闻个性化推荐

针对传统推荐系统中存在的冷启动、数据稀疏、语义缺乏、推荐精度较低等问题,提出一种基于事件本体的推荐算法。结合新闻的分类结构和新闻语料构建事件本体,对用户浏览的新闻进行要素抽取并构建用户兴趣模型。基于事件本体的分类结构计算新闻事件之间的相似度,通过用户兴趣模型计算用户兴趣相似度,根据事件本体非层次结构的语义半径寻找相关新闻事件。综合事件本体相似度、用户兴趣相似度和非层次结构相似度3个方面得出新闻个性化推荐结果。实验结果表明,该算法的推荐结果优于协同过滤推荐算法和基于内容的推荐算法。     

基于融合相似度和层次聚类的冷启动推荐算法

为了缓解协同过滤推荐算法中的用户冷启动问题,提出一种基于融合相似度和层次聚类的冷启动推荐算法.首先,基于用户的人口统计学信息、用户对项目的评分信息和项目种类信息,提出一种融合相似度计算方法;其次,基于用户的人口统计学信息,利用层次聚类确定冷启动用户的初始近邻用户集;最后,基于初始近邻用户集,利用融合相似度为目标用户进行...     

基于社交和地理信息的兴趣点推荐

目前基于用户的协同过滤兴趣点推荐模型认为两个用户之间对彼此的影响是相同的；同时，在计算社交用户相似度时仅仅考虑了用户的朋友集合，未考虑用户住所的地理信息。针对上述问题，提出了一种融合用户、社会和地理信息的兴趣点推荐（Fuse Users、Social and Geographic，FUSG）模型。将非对称用户影响和PageRank算法融入到基于用户的协同过滤算法中，挖掘用户偏好对兴趣点推荐系统的影响；结合社交用户之间的居住距离和用户的共同好友计算用户之间的相似度；利用地理信息挖掘用户签到的地理特征；将改进的协同过滤算法、社交信息与地理信息融合成FUSG模型，进行兴趣点推荐。在真实的数据集上的实验结果表明，FUSG模型不仅能够缓解冷启动问题，且与其他模型相比具有更高的推荐结果。     

基于用户兴趣度和特征的优化协同过滤推荐

协同过滤技术目前被广泛应用于个性化推荐系统中。为了使用户的最近邻居集合更加精确有效,提出了基于用户兴趣度和用户特征的优化协同过滤推荐算法。首先通过计算用户对项目的兴趣度来对用户进行分组;然后采用贝叶斯算法分析出用户具有不同特征时对项目的喜好程度;最后采用一种新的相似度度量方法计算出目标用户的最近邻居集合。实验表明该算法提高了最近邻居集合的有效性和准确度,推荐质量较以往算法有明显提高。     

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     

煤矿井下安全监控分站的设计及其仿真实现

为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.     

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。