Web开发中高效安全的数据持久层研究

本文阐述了企业数据的重要性,分析了当前流行的持久层解决方案的优缺点,并给出了基于XML的设计模式,建立一个高性能、高安全性、有弹性、可拓展性的数据持久层的方法.同时用一个信息查询的完整业务流程解释了持久性框架的主要设计思想.     

对象序列化技术在HLA仿真数据处理中的应用

在仿真数据的处理过程中,数据的持久存储以及在不同应用间的交互是需解决的关键问题。在面向对象领域,对象持久能力是使对象具备持久保存和动态恢复自身的能力,这一特点可用于构建仿真数据的持久存储和交互格式。对象序列化技术是支持对象实现持久性的重要机制,对此研究了一种将对象序列化技术改造用于高层体系结构（HLA）仿真数据处理的方法。该技术方法已经应用在作战仿真领域的实际系统中,结果表明基于对象序列化的仿真数据持久存储和交互格式使用起来更加方便并使数据处理效率得到提高。     

基于J2EE多层架构的Web开发框架研究*

在经典的J2EE四层体系结构的基础上增加数据持久层,提出了基于J2EE五层体系结构的Web开发框架;分析了基于Struts框架的J2EE架构中实现对象持久性的局限性,从中分离出对象持久层,并将Hibernate这个面向对象的轻量级对象持久性技术集成到该架构中;应用DAO设计模式在业务逻辑层与持久层之间设计了多源数据访问组件,抽象和封装了对不同数据源的数据访问操作,实现对不同类型、结构、环境、用法的异构数据库的统一访问。     

面向通用HPC的高性能DSP设计权衡

GPU由于其计算能力高达数TFLOPS,被高性能计算领域用于加速并行运算.但GPU较低的峰值性能利用率和功耗效率,已经成为了系统性能进一步提升的瓶颈.为了解决这个问题,作者开始研究将高性能DSP用于通用高性能计算领域.为了高效支撑通用高性能计算,文中提出了高性能DSP的结构框架,并通过映射GotoBLAS库到该结构上,建立了GEMM在该结构上的性能模型.作者研究了影响GEMM效率的主要因素,包括性能、存储层次、核的大小以及核的数量.文中总结了一些有指导意义的结论用于构建面向通用高性能计算的高效DSP.实验结果表明,通过尽可能少的硬件代价,可以在TFLOPS DSP上获得接近峰值的性能.     

OODB的支撑技术—持久程序设计语言（O＋＋和E的探讨）

持久程序设计语言是实现当前很有发展前途的面向对象数据库的一种支撑技术。这种技术是通过面向对象程序设计语言的扩充，使之具有持久存储的设施，从而能够用来构造出关系数据库中任意复杂的持久的数据结构。本文主要介绍了Ｏ＋＋和Ｅ这两种具有代表性的持久程序设计语言，并描述了如何解决在实现面向对象数据库过程中所遇到的诸如隐蔽指针、持久性和数据类型的无关性等几种困难问题。文章还比较了这两种语言的优缺点，希望能对面向     

基于OMNet＋＋的主从式异构物联网仿真平台的研究

本文分析并研究了融合GPRS和WLAN网络协议的主从式异构网络的物联网的系统性能,通过在OMNet＋＋框架内进行建模,搭建仿真平台。在这种网络模型中,传感器网络的主节点同时作为局域网网关工作。通过仿真实际异构物联网场景的性能测试,研究网络延时、正确送达率与节点数量、报文长度等的关系,以实现在大规模搭建传感器网络前根据具体的网络性能和通信质量要求进行整体部署。     

Hibernate对象管理研究

该文分析了Hibernate框架在应用程序持久层的位置、原理和重要意义。深入研究了Hibernate对象生命周期中的三种状态及其转化关系,并用实际开发中的典型程序段进行了直观形象地说明。阐明了Hibernate的Session缓存对数据持久性能的优化机制[1]。对准确、高效地操作Hibernate对象,编写高质量的持久层应用程序具有重要的参考价值。     

Hibernate对象管理研究

该文分析了Hibernate框架在应用程序持久层的位置、原理和重要意义。深入研究了Hibernate对象生命周期中的三种状态及其转化关系,并用实际开发中的典型程序段进行了直观形象地说明。阐明了Hibernate的Session缓存对数据持久性能的优化机制[1]。对准确、高效地操作Hibernate对象,编写高质量的持久层应用程序具有重要的参考价值。     

持久性操作系统及其相关技术

在正交持久性系统中，所有数据都是持久的，并可用相同的方式访问。程序设计语言层面的持久性支持具有性能低下、功能重复等缺点，操作系统级别的持久性支持才是更好的解决方案。本文首先介绍正交持久性的概念，然后分析持久性操作系统的需求并给出它的定义，接下来讨论持久性地址空间、影式分页和日志式分页等技术，最后研究一个持久性操作系统一GIrasshopper的设计。     

基于HLA/RTI的供配电仿真系统设计

针对传统供配电仿真系统的不足,本文提出基于HLA／RTI设计仿真系统框架,同时使用VegaPrime软件和Creator完成实时视景的开发,综合Visual C＋＋编程最终实现了一个具有一定先进性的供配电综合仿真系统。实践表明该仿真系统不仅可以用作电力运营的辅助工具,还可以为决策人员提供数据支持和决策建议,同时,还可用于对电力人员进行培训。     

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。