Java多线程编程中线程生存期和优先级的探讨

在Java多线程编程中,理解线程的生存期和优先级是编制多线程程序的基础。本文主要介绍了Java多线程机制的线程生存期和优先级的原理,线程的生存期和优先级决定着整个线     

多线程技术基于VB．NET的实现

多线程技术是实现需要并发执行的应用程序的较好选择,具有不可替代的作用。文中介绍了进程、线程以及应用程序域的概念及其相互之间的关系,讨论了VisualBasic.NET对多线程的支持。并从线程的创建与管理、线程取消、线程的优先级、线程的状态、线程池、线程的同步等方面展示了如何使用多线程编程技术来创建多线程应用程序。每个线程都需要资源,创建的线程过多,反而会降低应用程序的性能。在设计多线程应用程序时,应慎重对待,建立合理的系统模型,才能使应用程序获得最佳的性能。     

多线程技术基于VB.NET的实现

多线程技术是实现需要并发执行的应用程序的较好选择,具有不可替代的作用.文中介绍了进程、线程以及应用程序域的概念及其相互之间的关系,讨论了Visual Basic.NET对多线程的支持.并从线程的创建与管理、线程取消、线程的优先级、线程的状态、线程池、线程的同步等方面展示了如何使用多线程编程技术来创建多线程应用程序.每个线程都需要资源,创建的线程过多,反而会降低应用程序的性能.在设计多线程应用程序时,应慎重对待,建立合理的系统模型,才能使应用程序获得最佳的性能.     

Java多线程下载技术

线程可以理解为下载的通道,一个线程就是一个文件的下载通道,多线程也就是同时开起好几个下载通道.当服务器提供下载服务时,使用下载者是共享带宽的,在优先级相同的情况下,总服务器会对总下载线程进行平均分配.线程越多,下载速度越快.当前的下载软件都支持多线程技术.     

基于Windows CE平台的多线程编程

windows CE是一个支持多线程的操作系统。本文介绍了基于Windows CE平台的多线程编程方法，主要包括多线程的创建，线程的优先级，多线程同步问题等，最后给出了多线程技术在双输入双输出控制模拟系统中的一个应用实例。     

多线程在CCD测量系统中的应用

介绍了在Windows NT系统中如何创建多线程并提升线程优先级.文章针对一个具体的CCD(charge-coupled device)测量系统进行了详细地论述,并就该测量系统软件中各线程之间的关系及它们的优先级进行了讨论.最后对此系统中使用的多线程技术进行了分析.以上的设计思路在该CCD测量系统课题中得到了很好的应用,具有广泛的实际应用价值.     

lwThread：轻量级通用多线程

针对嵌入式系统开发中多线程技术可移植性较差的问题,提出一种通用的轻量级多线程模型——lwThread,采用标准C语言实现,在源程序级实现线程的切换。与同类技术相比,lwThread不但可以实现线程的优先级,还可以为每个线程动态分配独立的栈空间,同时介绍确定共享栈池大小的理论依据。实验结果表明,lwThread模型可以有效提高开发效率,并降低资源消耗。     

基于二型模糊逻辑的多线程数据竞争检测方法研究

多线程机制以其诸多优势在程序开发中被广泛使用,然而随着多线程软件规模的增长,程序中潜存着许多并发缺陷,最常见的并发缺陷是数据竞争和死锁。目前,针对这些并发缺陷的检测手段都无法处理线程时序的不确定性,无法处理运行时环境对线程时序的影响,同时也不能计算这些并发缺陷发生的概率并根据概率生成其处理优先级。针对以上问题,提出了一种基于二型模糊逻辑的多线程数据竞争检测方法。该方法将传统的多线程时序分析和缺陷检测方法作为预处理,考虑程序运行时环境因素对线程时序的影响,利用二型模糊逻辑和隐马尔科夫模型对待检测程序建模,计算待检测程序在某一系统负载下的时序概率,并根据时序概率生成时序缺陷处理优先级列表供软件开发人员参考。     

一种具有QoS特性的同时多线程处理器取指策略

同时多线程处理器通过每时钟周期从多个运行的线程取指令执行,从而极大地提高了处理器的性能．建议了一种具有QoS特性的同时多线程处理器取指策略,并讨论了其在QoS管理方面的问题．该策略的核心思想是利用线程的优先级和流速来同时控制线程的取指过程,从而满足线程在执行速度上的QoS需求．与传统的基于纯优先级的取指策略相比,该策略不但具有QoS特性,同时还可以更加有效地分配取指带宽,从而能获得更高的处理器性能．该策略的物理实现非常简单．模拟实验的结果表明,该策略在提供Qos支持的基础上,可以在传统的基于优先级的取指策略ICOUNT的基础上提高15％的系统性能．     

基于线程流水线的多核线程调度策略

针对多核环境中操作系统的线程调度问题,提出一种基于线程流水线的线程调度策略。基于片上多线程处理器,借鉴流水线技术的并行优势,引入线程流水线的概念。通过确定线程特征指标,计算线程流水线的聚合度及对应线程的吻合度,从而完成线程调度,并在此基础上对其进行嵌入式方向的优化。模拟真实环境的实验结果表明,与基于静态优先级的调度策略相比,该策略消耗时间较少。     

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。