Redundancy Allocation for Series-Parallel Systems Using Integer Linear Programming

We consider the problem of maximizing the reliability of a series-parallel system given cost and weight constraints on the system. The number of components in each subsystem, and the choice of components are the decision variables. In this paper, we propose an integer linear programming approach that gives an approximate feasible solution, close to the optimal solution, together with an upper bound on the optimal reliability. We show that integer linear programming is a useful approach for solving this reliability problem. The mathematical programming model is relatively simple. Its implementation is immediate by using a mathematical programming language, and integer linear programming software. And the computational experiments show that the performance of this approach is excellent based on a comparison with previous results.      

可编程控制器的梯形图语言与语句表语言的互换算法

当代可编程控制器对多种语言的编程支持使可编程控制器为广大工程的技术人员和操作人员所广泛使用。而众多的编程语言中,梯形图语言和语句表语言最为受欢迎。文章介绍了梯形图语言与语句表语言之间的互换算法。并以ＯＭＲＯＮ Ｃ系列可编程控制器为例做以说明。     

Real-time schedulability-analyzable mechanisms in Ada9X

The paradigm of computing defined by real-time applications places significant requirements on programming languages, among them (1) interfacing to hardware devices, (2) maintainability, portability, reliability, and safely, (3) fault tolerance, and nonstop operation; (4) concurrency, and (5) achieving correct timing predictably (and the consequent paramount schedulability analyzability requirement). We trace how these requirements affect various mechanisms of a typical programming language. Ada9X-a new emerging standard for Ada-is then illustrated as an example of a serious attempt to address these requirements in a programming language standard. While Ada9X is far from perfect, it is a significant step, and we are hopeful for the trend of schedulability analyzable languages to gain momentum and continue     

High-level protocols

High-level protocols (HLP's) are the high-level languages of distributed systems. In a resource-sharing network, HLP's link processes working on a conmmn application. The design of an HLP is decomposed into three components: language, coding, and transport. The language expresses the commands and data passed between processes. It is designed to provide standardization and device independence, in order to use a small number of HLP's to address a range of applications implemented on a variety of computer systems. Coding converts the language into digital messages. Finally, a transport system is used to transmit the messages from one process to another-experience with HLP's has shown that different HLP's require different transport behaviors. This paper describes some examples of HLP's (ARPA network voice and graphics protocols), and argues that modern techniques for expressing structure and control in programming languages should be applied to analogous problems in communication among application processes in a network.     

A note on solving a system reliability problem involving nonlinear constraints

This paper is concerned with maximizing a system reliability function subject to nonlinear constraints. Numerical examples from the literature are handled by a general nonlinear programming algorithm, which can deal with the positive-integer variables of this reliability problem without special difficulties. The computational results presented in this paper suggest that the computer program listed here can be useful as a model for maximizing the system reliability function subject to the nonlinear constraints used here. In addition, because of the general applicability of the nonlinear programming algorithm, other system reliability functions and nonlinear constraints different from the ones used in this paper can also be accommodated.     

面向对象程序设计语言研究现状

面向对象程序设计已成为一种重要的程序设计范型，被广为接受和使用，数量众多的程序设计语言提供了对这种范型的支持，本文综述了面向对象程序设计语言的研究现状，着重讨论了如下几方面的问题：语义研究、类型系统、语言特性、分布性、语言的变种及Ｓｍａｌｌｔａｌｋ等。     

面向对象语言BDOL及其支撑环境

本文介绍一种面向对象语言ＢＤＯＬ，它既是系统规范设计语言，又是系统实现编程语言，ＢＯＤＬ语言支持多种面向对象程序设计语言，如Ｃ＋＋、Ｓｍａｌｌｔａｌｋ、ＣＬＯＳ等的混合编程，从而使语言表达能力增强，更加灵活，同时也能达到更有效的软件复用。     

数据信息动态生成图表的方法

为了使各种编程语言都可以编写符合OLE DB标准的应用程序,微软在OLE DB API之上,提供了一种面向对象、与语言无关的应用程序接口,这就是ADO（ActiveX Data Objects）控件.本文介绍利用Visual Basic中ADO（ActiveX Data Objects）与Chart控件结合将数据库的数据信息动态生成图表的方法,他有效地解决了将数据转化为直观图表这一在实际中经常遇到的问题.     

Multithreaded languages for scientific and technical computing

An overview of language support for parallel technical computing is provided. The rationale for multithreaded languages, in which the programmer explicitly specifies what work is to be carried out by multiple processors and how their activities should be coordinated, is described. The discussion begins with an introduction to the general models for manipulating multiple threads and how they are incorporated into programming languages. The wide variety of features for creating multiple threads, scheduling their execution, synchronizing their activities, and sharing data among them are then examined. Examples in a simplified, FORTRAN-like notation are included. It is shown how the language features are distributed among commercial compiler implementations. Some less traditional approaches to multithreaded language support are presented to provide a glimpse at what might be expected in future languages and compilers     

基于FPGA的CRC编解码器实现

循环冗余校验(CRC)是一种广泛应用于通信领域以提高数据传输可靠性的差错控制方法。介绍了CRC码的原理,分析了CRC编码、解码电路设计思路。利用VHDL语言设计CRC(7,3)编解码器并通过QuartusⅡ仿真平台进行仿真验证,最后下载到FPGA芯片实现了CRC(7,3)编解码电路。仿真及实验结果表明采用此方法实现的CRC编解码器具有速度快、可靠性高及易于大规模集成的优点。     

Programming—An introduction

The aim of this paper is to introduce the fundamental ideas of programming, and to show why programming languages are necessary. Various levels of language will be considered and the implmentation of one of them on different microprocessor systems will be discussed. Finally the different stages in software development will be described together with the nature of operating systems.     

Stochastic programming models for general redundancy-optimization problems

This paper provides a unified modeling idea for both parallel and standby redundancy optimization problems. A spectrum of redundancy stochastic programming models is constructed to maximize the mean system-lifetime, /spl alpha/-system lifetime, or system reliability. To solve these models, a hybrid intelligent algorithm is presented. Some numerical examples illustrate the effectiveness of the proposed algorithm. This paper considers both parallel redundant systems and standby redundant systems whose components are connected with each other in a logical configuration with a known system structure function. Three types of system performance-expected system lifetime, /spl alpha/-system lifetime and system reliability-are introduced. A stochastic simulation is designed to estimate these system performances. In order to model general redundant systems, a spectrum of redundancy stochastic programming models is established. Stochastic simulation, NN and GA are integrated to produce a hybrid intelligent algorithm for solving the proposed models. Finally, the effectiveness of the hybrid intelligent algorithm is illustrated by some numerical examples.     

基于大数据的C语言程序设计

C语言作为一种程序设计语言,在大数据组成的物联网和云计算中应用广泛,具有强大的适应性和兼容性,是大数据时代下,在IT行业中起到关键作用的程序设计语言。文章分析了基于大数据的C语言程序设计的必然性和应用策略,为C语言在大数据上的应用方向提供了参考依据。以汉字的应用为例,提出了解决C语言应用问题的思路。     

高职院校“Python语言”课程教学探讨

计算机编程是计算机专业的学生必须掌握的一种重要技能。对于非计算机专业的高职生来说,传统的编程语言如C语言、VB语言等都是比较难学的、枯燥的编程语言。作为当今最流行的编程语言,"Python语言"具有开源、易学等特点。为了提高非计算机专业的高职生的编程兴趣,以更好地培养学生的逻辑思维,调动学生的学习兴趣为目的,文章对高职院校"Python语言"课程教学进行了探讨。     

计算机软件Java编程特点及其技术运用探讨

随着我国科学技术的快速发展,计算机软件技术也在不断的更新换代,在这样的时代背景下,Java计算机软件编程语言技术的应用范围逐渐变得广泛。与其他的编程语言相比,Java计算机软件编程语言技术具有简单易操作、安全系数高、灵活性强的特点。基于此,Java计算机软件编程语言技术能够有效提高计算机软件研发的质量及效率,极大促进我国计算机软件研发技术的发展。因此,文中探讨了计算机软件Java计算机软件编程语言技术的特点及该技术的实际应用,研究了计算机软件Java计算机软件编程语言技术的未来发展前景,以期为相关人员提供参考。     

Use of hybrid models for testing and debugging control software for electromechanical systems

This paper proposes a hybrid modeling language and its application to a simulator-based testing and debugging environment for the control software for electromechanical systems. The new hybrid modeling language is designed mainly focusing on simulation speed, flexibility in connecting with control software, and model reusability. This language maintains the advantages of existing hybrid modeling languages such as Hybrid cc, including the flexibility of constraint programming and the reusability of the object-oriented approach. A new feature of the language is that it allows combination of compositional constraint programming and sequential procedural programming. The compiled code is executed efficiently by the runtime system, which has a built-in mechanism for communicating with external software, eliminating the complicated setup required for integrating the simulator with the control software. Model components programmed by the object-oriented approach allow designers to use existing components and to concentrate on the task of modeling the newly designed hardware. The runtime system has been integrated with a three-dimensional kinematics simulator and a control software design tool to create a simulator-based testing and debugging environment. The effectiveness of this system has been confirmed through its application to real product design projects.     

计算机软件Java编程特点及其技术分析

计算机技术的快速发展与普及对人们的生产生活方式都产生了巨大的改变,其在提高人们生产生活质量和效率方面发挥着重要的作用。在计算机技术中,软件是尤为重要的组成部分,而Java编程技术则是计算机软件中最为核心的语言之一。Java编程语言具有安全、可靠的特点,对提高软件开发水平,以及提高计算机水平都具有重要的意义。基于此,文章就对计算机软件Java编程特点及其技术进行详细分析。     

SeSFJava harness: service and assertion checking for protocol implementations

Many formal specification languages and associated tools have been developed for network protocols. Ultimately, formal language specifications have to be compiled into a conventional programming language and this involves manual intervention (even with automated tools). This manual work is often error prone because the programmer is not familiar with the formal language. So our goal is to verify and test the ultimate implementation of a network protocol, rather than an abstract representation of it. We present a framework, called services and systems framework (SeSF), in which implementations and services are defined by programs in conventional languages, and mechanically tested against each other. SeSF is a markup language that can be integrated with any conventional language. We integrate SeSF into Java, resulting in what we call SeSFJava. We present a service-and-assertion checking harness for SeSFJava, called SeSFJava harness, in which distributed SeSFJava programs can be executed, and the execution checked against services and any other correctness assertions. The harness can test the final implementation of a concurrent system. We present an application to a data transfer service and sliding window protocol implementation. SeSFJava and the harness has been used in networking courses to specify and test transmission control protocol-like transport protocols and service.     

Times Square – Marriage of Real-Time and Logical-Time in GALS and Synchronous Languages

In this paper we introduce exact and non-exact real-time waits in the reactive Globally Asynchronous Locally Synchronous (GALS) programming languages and synchronous languages as their subset. The language constructs that allow use of real-time waits are illustrated on the SystemJ GALS language. They allow system designers to explicitly use, at the specification level, not only logical time but also real-time in order to control program execution. We transform the real-time constructs into a logical model of time, and statically bound the amount of delay introduced by these constructs. In addition, the introduced concepts utilize execution platforms that allow finding best and worst reaction time of a GALS or synchronous program.     

Application of the surrogate constraints algorithm to optimal reliability design of systems

This paper presents a solution method for the reliability optimization problem of series-parallel systems which is formulated as a mixed integer nonlinear programming problem with multiple constraints. In the solution method, the optimal solution is obtained by solving the surrogate dual problem. Surrogate problems with only one constraint which appear in the optimization process are solved by a technique using dynamic programming. Some computational experiences are shown along with the comparison with an existing approach.