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81.
介绍一种利用数据挖掘技术开发金融数据分析模块的设计和实现,使用Microsoft SQL Server Analysis Services服务技术进行分析和预测。该模块的运行可以有效提高金融分析员的工作效率。  相似文献   
82.
提出一个新的P2P网络研究问题,即BitTorrent类型对等网络(采用了相似的多源文件传输机制的P2P网络)的位置知晓性问题.设计了BT类型网络使用的具有理想位置知晓性的多源文件传输机制,进行了数学建模,分析证明了该机制具有良好的位置知晓性、下载性能、网络公平性和扩展性.  相似文献   
83.
开放性高校信息系统中Web Services的研究与应用   总被引:1,自引:1,他引:0  
在分析了现存高校信息系统的应用现状和Web服务技术的基础上,针对现存主流的高校信息系统中存在的问题和Web服务的技术特点,提出了着重应用Web服务技术提升高校信息系统的对外服务的开放性的开发思路,使得企业等社会机构能更充分利用其科研资源.此外还对应用的具体开发平台.NET中相关技术进行了相应的分析.  相似文献   
84.
随着构建系统的复杂性日益增强,基于原有的基础层次结构的构建方式将逐渐不能满足扩展的需求变化,因此,在原有的层次结构中进行一步抽象,建立一种新的层次结构;它是在J2EE框架下采用3款轻量级开源件Struts、Spring和ibatis进行构建,并把相应的开源件以及Web服务标准的相关技术和Ajax技术融合到各层中去,然后包装成一种基于Web的通用框架,同时结合一个高校评估系统(Hsvs)来使用该框架.这样,就可以实现数据与业务逻辑无缝访问,业务逻辑与表现逻辑高松散低耦合分离,以及降低开发人员的繁琐编码,增强软件的可扩展性和增长生命周期.  相似文献   
85.
刘雅娟 《计算机时代》2009,(7):48-49,52
目前高校内各部门的管理信息系统都拥有独立的记录登录日志和读取登录日志的模块,从而造成了业务逻辑的重复和数据的冗余。针对这种情况提出了一种基于WebServices的系统登录日志技术,使各异构系统能够统一调用登录日志的WebServices。这种方案充分利用了现有的网络资源,有效地避免数据与业务逻辑的冗余,实现了模块和数据的重用。  相似文献   
86.
出行信息服务关键技术研究进展与问题探讨   总被引:2,自引:1,他引:1       下载免费PDF全文
随着城市交通出行需求的不断增长.出行信息服务应运而生.介绍了出行信息服务产业的国内外发展状况,提出了出行信息服务技术平台的体系结构.分析了通讯平台、定位平台和地图平台的地位、作用及其发展趋势.从交通信息采集与处理、空间数据模型、路径规划算法、短时交通预测、信息可视化和服务标准规范等方面评述了关键技术的研究进展,分析了出行信息服务产业发展需要重点解决的科学与技术问题.以促进出行信息服务技术研究的进一步深化.  相似文献   
87.
针对基于Web的有色金属物性数据库的访问特点,分析了有色金属物性数据库在多层架构体系中存在的非法入侵、越权访问、信息重放攻击等安全性问题,提出了适应其软件架构要求的安全访问控制模型.并对所提出的安全模型分别进行了访问性能和安全性测试,测试结果表明,访问模型安全性较好,性能稳定.  相似文献   
88.
Interest in the Web services (WS) composition (WSC) paradigm is increasing tremendously. A real shift in distributed computing history is expected to occur when the dream of implementing Service-Oriented Architecture (SOA) is realized. However, there is a long way to go to achieve such an ambitious goal. In this paper, we support the idea that, when challenging the WSC issue, the earlier that the inevitability of failures is recognized and proper failure-handling mechanisms are defined, from the very early stage of the composite WS (CWS) specification, the greater are the chances of achieving a significant gain in dependability. To formalize this vision, we present the FENECIA (Failure Endurable Nested-transaction based Execution of Composite Web services with Incorporated state Analysis) framework. Our framework approaches the WSC issue from different points of view to guarantee a high level of dependability. In particular, it aims at being simultaneously a failure-handling-devoted CWS specification, execution, and quality of service (QoS) assessment approach. In the first section of our framework, we focus on answering the need for a specification model tailored for the WS architecture. To this end, we introduce WS-SAGAS, a new transaction model. WS-SAGAS introduces key concepts that are not part of the WS architecture pillars, namely, arbitrary nesting, state, vitality degree, and compensation, to specify failure-endurable CWS as a hierarchy of recursively nested transactions. In addition, to define the CWS execution semantics, without suffering from the hindrance of an XML-based notation, we describe a textual notation that describes a WSC in terms of definition rules, composability rules, and ordering rules, and we introduce graphical and formal notations. These rules provide the solid foundation needed to formulate the execution semantics of a CWS in terms of execution correctness verification dependencies. To ensure dependable execution of the CWS, we present in the second section of FENECIA our architecture THROWS, in which the execution control of the resulting CWS is distributed among engines, discovered dynamically, that communicate in a peer-to-peer fashion. A dependable execution is guaranteed in THROWS by keeping track of the execution progress of a CWS and by enforcing forward and backward recovery. We concentrate in the third section of our approach on showing how the failure consideration is trivial in acquiring more accurate CWS QoS estimations. We propose a model that assesses several QoS properties of CWS, which are specified as WS-SAGAS transactions and executed in THROWS. We validate our proposal and show its feasibility and broad applicability by describing an implemented prototype and a case study.  相似文献   
89.
Traditionally, direct marketing companies have relied on pre-testing to select the best offers to send to their audience. Companies systematically dispatch the offers under consideration to a limited sample of potential buyers, rank them with respect to their performance and, based on this ranking, decide which offers to send to the wider population. Though this pre-testing process is simple and widely used, recently the industry has been under increased pressure to further optimize learning, in particular when facing severe time and learning space constraints. The main contribution of the present work is to demonstrate that direct marketing firms can exploit the information on visual content to optimize the learning phase. This paper proposes a two-phase learning strategy based on a cascade of regression methods that takes advantage of the visual and text features to improve and accelerate the learning process. Experiments in the domain of a commercial Multimedia Messaging Service (MMS) show the effectiveness of the proposed methods and a significant improvement over traditional learning techniques. The proposed approach can be used in any multimedia direct marketing domain in which offers comprise both a visual and text component.
Giuseppe TribulatoEmail:

Sebastiano Battiato   was born in Catania, Italy, in 1972. He received the degree in Computer Science (summa cum laude) in 1995 and his Ph.D in Computer Science and Applied Mathematics in 1999. From 1999 to 2003 he has lead the “Imaging” team c/o STMicroelectronics in Catania. Since 2004 he works as a Researcher at Department of Mathematics and Computer Science of the University of Catania. His research interests include image enhancement and processing, image coding and camera imaging technology. He published more than 90 papers in international journals, conference proceedings and book chapters. He is co-inventor of about 15 international patents. He is reviewer for several international journals and he has been regularly a member of numerous international conference committees. He has participated in many international and national research projects. He is an Associate Editor of the SPIE Journal of Electronic Imaging (Specialty: digital photography and image compression). He is director of ICVSS (International Computer Vision Summer School). He is a Senior Member of the IEEE. Giovanni Maria Farinella   is currently contract researcher at Dipartimento di Matematica e Informatica, University of Catania, Italy (IPLAB research group). He is also associate member of the Computer Vision and Robotics Research Group at University of Cambridge since 2006. His research interests lie in the fields of computer vision, pattern recognition and machine learning. In 2004 he received his degree in Computer Science (egregia cum laude) from University of Catania. He was awarded a Ph.D. (Computer Vision) from the University of Catania in 2008. He has co-authored several papers in international journals and conferences proceedings. He also serves as reviewer numerous international journals and conferences. He is currently the co-director of the International Summer School on Computer Vision (ICVSS). Giovanni Giuffrida   is an assistant professor at University of Catania, Italy. He received a degree in Computer Science from the University of Pisa, Italy in 1988 (summa cum laude), a Master of Science in Computer Science from the University of Houston, Texas, in 1992, and a Ph.D. in Computer Science, from the University of California in Los Angeles (UCLA) in 2001. He has an extensive experience in both the industrial and academic world. He served as CTO and CEO in the industry and served as consultant for various organizations. His research interest is on optimizing content delivery on new media such as Internet, mobile phones, and digital tv. He published several papers on data mining and its applications. He is a member of ACM and IEEE. Catarina Sismeiro   is a senior lecturer at Imperial College Business School, Imperial College London. She received her Ph.D. in Marketing from the University of California, Los Angeles, and her Licenciatura in Management from the University of Porto, Portugal. Before joining Imperial College Catarina had been and assistant professor at Marshall School of Business, University of Southern California. Her primary research interests include studying pharmaceutical markets, modeling consumer behavior in interactive environments, and modeling spatial dependencies. Other areas of interest are decision theory, econometric methods, and the use of image and text features to predict the effectiveness of marketing communications tools. Catarina’s work has appeared in innumerous marketing and management science conferences. Her research has also been published in the Journal of Marketing Research, Management Science, Marketing Letters, Journal of Interactive Marketing, and International Journal of Research in Marketing. She received the 2003 Paul Green Award and was the finalist of the 2007 and 2008 O’Dell Awards. Catarina was also a 2007 Marketing Science Institute Young Scholar, and she received the D. Antonia Adelaide Ferreira award and the ADMES/MARKTEST award for scientific excellence. Catarina is currently on the editorial boards of the Marketing Science journal and the International Journal of Research in Marketing. Giuseppe Tribulato   was born in Messina, Italy, in 1979. He received the degree in Computer Science (summa cum laude) in 2004 and his Ph.D in Computer Science in 2008. From 2005 he has lead the research team at Neodata Group. His research interests include data mining techniques, recommendation systems and customer targeting.   相似文献   
90.
This study presents a new Y-channel design for measuring the zeta potential and surface conductance of a solid-liquid pairing using the current monitoring technique. The new design improves the throughput and reliability of the testing apparatus since the displacement between two solutions can be repeated many times without interfering with the experiments. It also increases the accuracy of the measurement by producing sharper start and end transitions for the current–time plot of the solution displacement process. In this design, efforts have been made to minimize the effects of electrolysis, Joule heating and undesired pressure driven flow on the measurements. An improvement on the current–time slope analysis is also presented. The Y-channel design was validated by comparing zeta potential measurements to published results. The zeta potential of several biological buffers relevant to the microfluidic community in plasma treated PDMS/PDMS and PDMS/Glass microchannels are presented. Preliminary studies of surface conductivity measurements using the Y-channel design were also conducted and are briefly discussed.  相似文献   
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