多测试仪表数据采集与控制系统的设计与实现

为满足工业现场中对多种不同类型仪表进行集中监视、统一控制要求,设计一种多测试仪表数据采集与控制系统,该系统基于TCP／IP协议进行通信,使用VC进行编程,采用select模型、多线程技术以及扫描技术,实现对多种不同类型的测试仪表的动态接入和并发控制,并介绍一种面向对象的设计方案,以实现对多种不同类型仪表的兼容。     

基于UML语音发票查询系统的研究及应用

UML建模是面向对象技术的一个重要应用，也是近代软件工程环境中对象分析和设计的重要工具。本文首先介绍了UML的建模原理，然后结合海口地税语音发票查询系统项目的分析设计过程，对UML技术的具体应用作了详细的描述。     

基于公理系统的面向对象自动测试研究

文章提出了一个基于公理系统的面向对象自动测试框架.该框架首先从XML文件中提取被测类的代数规格说明和公理描述,然后使用‘term rewriting'技术生成‘消息对'形式的测试用例,最后使用velocity模板引擎使测试用例可以在Junit单元测试工具上自动执行和验证.     

Kanga(ROO): Handling the micro-DST of the BaBar experiment with ROOT

A system based on ROOT for handling the micro-DST of the BaBar experiment is described. The purpose of the Kanga system is to have micro-DST data available in a format well suited for data distribution within a world-wide collaboration with many small sites. The design requirements, implementation and experience in practice after three years of data taking by the BaBar experiment are presented.     

基于BP的NC凸轮轴磨床磨削参数优化软件设计

为提高凸轮轴的加工精度和表面质量、提高加工效率 ,针对开放式数控凸轮轴磨床 ,以实际的凸轮轴加工为例 ,运用BP神经网络对磨削参数和其各种影响因素进行建模。并利用面向对象的编程语言VC ,开发了基于BP神经网络的磨削参数选择模块。该程序具有良好操作性、扩展性和通用性     

Object-oriented approach applied to ANFIS modeling and control of a distillation column

Neurofuzzy networks are hybrid systems that combine neural networks with fuzzy systems, and the Adaptive Neuro-Fuzzy inference system (ANFIS) is a particular case in which a fuzzy system is implemented in the framework of an adaptive neural network. This neurofuzzy approach represents an effective structure to the modeling of plant dynamics, and the oriented-object programming environments offer an intuitive way to address this task. In this paper the MODELICA object-oriented environment has been applied to the ANFIS modeling and indirect control of the heavy and light product composition in a binary methanol-water distillation column by using the adaptive Levenberg–Marquardt approach. The results obtained demonstrate the potential of the adaptive ANFIS scheme under MODELICA for the dual control of composition both for changes in set points with null stationary error even when disturbances are present.     

A graph-theoretic model for optimizing queries involving methods

Traditional algorithms for optimizing the execution order of joins are no more valid when selections and projections involve methods and become very expensive operations. Selections and projections could be even more costly than joins such that they are pulled above joins, rather than pushed down in a query tree. In this paper, we take a fundamental look at how to approach query optimization from a top-down design perspective, rather than trying to force one model to fit into another. We present a graph model which is designed to characterize execution plans. Each edge and each vertex of the graph is assigned a weight to model execution plans. We also design algorithms that use these weights to optimize the execution order of operations. A cost model of these algorithms is developed. Experiments are conducted on the basis of this cost model. The results show that our algorithms are superior to similar work proposed in the literature. Received 20 April 1999 / Accepted 9 August 2000 Published online 20 April 2001     

形式化描述语言B的面向对象机制研究

在分析B语言和面向对象方法的基础上,提出一种具有面向对象特性的形式化描述语言B ,该语言克服原有B语言没有机制形式描述一系列实例变量和不确定的行为的缺点。     

Delphi常见文件操作

介绍Delphi编程中传统文件操作与面向对象的流文件操作的方法,并举例说明面向对象的流文件操作的优势。     

Model-based cache-aware dispatching of object-oriented software for multicore systems

In recent years, processor technology has evolved towards multicore processors, which include multiple processing units (cores) in a single package. Those cores, having their own private caches, often share a higher level cache memory dedicated to each processor die. This multi-level cache hierarchy in multicore processors raises the importance of cache utilization problem. Assigning parallel-running software components with common data to processor cores that do not share a common cache increases the number of cache misses. In this paper we present a novel approach that uses model-based information to guide the OS scheduler in assigning appropriate core affinities to software objects at run-time. We build graph models of software and cache hierarchies of processors and devise a graph matcher algorithm that provides mapping between these two graphs. Using this mapping we obtain candidate core sets that each software object can be affiliated with at run-time. These affiliations are determined based on the idea that software components that have the potential to share common data at run-time should run on cores that share a common cache. We also develop an object dispatcher algorithm that keeps track of object affiliations at run-time and dispatches objects by using the information from the compile-time graph matcher. We apply our approach on design pattern implementations and two different application program running on servers using CFS scheduling. Our results show that cache-aware dispatching based on information obtained from software model, decreases number of cache misses significantly and improves CFS’ scheduling performance.