Data race avoidance and replay scheme for developing and debugging parallel programs on distributed shared memory systems

Distributed shared memory (DSM) allows parallel programs to run on distributed computers by simulating a global virtual shared memory, but data racing bugs may easily occur when the threads of a multi-threaded process concurrently access the physically distributed memory. Earlier tools to help programmers locate data racing bugs in non-DSM parallel programs are not easily applied to DSM systems. This study presents the data race avoidance and replay scheme (DRARS) to assist debugging parallel programs on DSM or multi-core systems. DRARS is a novel tool which controls the consistency protocol of the target program, automatically preventing a large class of data racing bugs when the parallel program is subsequently run, obviating much of the need for manual debugging. For data racing bugs that cannot be avoided automatically, DRARS performs a deterministic replay-type function on DSM systems, faithfully reproducing the behavior of the parallel program during run time. Because one class of data racing bugs has already been eliminated, the remaining manual debugging task is greatly simplified. Unlike previous debugging methods, DRARS does not require that the parallel program be written in a specific style or programming language. Moreover, DRARS can be implemented in most consistency protocols. In this paper, DRARS is realized and verified in real experiments using the eager release consistency protocol on a DSM system with various applications.     

基于单片机的小型程控交换机

本文介绍单片机在程控交换机中的应用,使用一个ATMEL公司的AT89C51作为主控制器,分时控制,结构简单,模块化程序结构。     

基于单片机的程控交换机多机通信应用

本文介绍单片机在程控交换机中的应用,使用五个ATMEL公司的AT89C52和AT89C51作为主控制器和从控制器,多机通讯,硬件结构清晰,模块化程序结构.     

支持多种并行程序设计模式的可移植并行调试器设计与实现

MPDG是为高性能并行巨型机系统设计的调试工具,其设计指导思想是：1．采用Client/Server结构,实现系统的可移植性,具体表现为将用户界面,并行调试管理与调试监控服务分离,调试监控采用目标系统支持的调试器;2．以同一的使用方式支持多种并行程序设计模式应用,针对共享内存的并行目标应用（如OpenMP程序)和基．于水息传递的分布式目标应用（如PVM或MPI程序）,提供风格完全一致的调试手段;3．实现图形用户界面,MPDG的GUI分为3级,即主界面,进程集,单个进程,进程集控制特别适合具有相同执行流和用户视图的并行进程的调试。     

Microprocessor techniques for energy conservation in computer rooms

Computers, particularly large ones used by finance bodies and government, are heavy users of electricity both to power the computer and to provide the environment recommended by the computer manufacturer. The power used by the environmental control equipment can be higher than that used by the computer itself. Both capital costs and running costs are high. Some cooling plants consume of the order of a megawatt of power. Recently, very expensive systems have been developed to recover waste heat from computers for use elsewhere in buildings either for hot water supplies or for space heating.This approach can only be easily applied to new custom designed installations, whereas in future most computers will be installed in existing buildings. Most heat is available from such systems in the summer when the demand is at a minimum. At best they are a palliative for an energy design which is wrong in concept.This article advocates an integrated approach to the total computer system design where all the factors, including energy consumption, are considered from the outset and their interactions considered. A working example is described designed on these principles which uses a fresh air ventilation system controlled by a microprocessor. Other advantages include automatic condition monitoring of the equipment, improved security and fire protection. The microprocessor-based environment controller is an order of magnitude cheaper, both in capital and running costs, than conventional designs. There is no evidence to suggest that it is less effective, because the computer installations concerned show higher than average reliability.     

Artificial intelligence techniques and their application in oil and gas industry

Artificial Intelligence Review - Data are being continuously generated from various operational steps in the oil and gas industry. The recordings of these data and their proper utilization have...     

CAI in digital logic design,debugging, and programming

This paper describes design techniques for generative computer-assisted instruction (CAI) systems. These are systems which are capable of generating problems for students and deriving and monitoring the solutions to these problems. The difficulty of the problem, the pace of instruction, and the depth of monitoring are all tailored to the individual student. Parts of the solution algorithms can also be used to analyze an incorrect student response and determine the exact nature of the student's error in order to supply him with meaningful remedial comments.A generative CAI system which teaches logic design and machine-language programming will be discussed. This CAI system covers the material in an introductory course in digital systems aimed at electrical engineering juniors. It does not replace classroom lectures or the textbook, but instead serves to provide practice and instruction in applying this material to solve problems.In addition, a companion system to teach laboratory principles has been designed. This system teaches a student how to construct a combinational or sequential logic circuit using standard integrated circuits. The student's logic circuit is automatically interfaced to the computer and tested; the computer then aids the student in debugging his circuit. In addition to teaching the student how to use integrated circuits to realize a paper design, the system also teaches the student good debugging techniques.     

Unix进程文件系统及其在调试器设计中的应用

进程文件系统比传统的ptrace系统调用具有效率高、功能强的优点,该文介绍了它的主要功能,并以调试器的设计为例,详细描述了进程文件系统的应用情况。     

New decision-making techniques and their application in the selection of financial products

We develop a new approach that uses the ordered weighted averaging (OWA) operator in the selection of financial products. In doing so, we introduce the ordered weighted averaging distance (OWAD) operator and the ordered weighted averaging adequacy coefficient (OWAAC) operator. These aggregation operators are very useful for decision-making problems because they establish a comparison between an ideal alternative and available options in order to find the optimal choice. The objective of this new model is to manipulate the attitudinal character of previous methods based on distance measures, so that the decision maker can select financial products according to his or her degree of optimism, which is also known as the orness measure. The main advantage of using the OWA operator is that we can generate a parameterized family of aggregation operators between the maximum and the minimum. Thus, the analysis developed in the decision process by the decision maker is much more complete, because he or she is able to select the particular case in accordance with his or her interests in the aggregation process. The paper ends with an illustrative example that shows results obtained by using different types of aggregation operators in the selection of financial products.     

Tactile displays: guidance for their design and application

OBJECTIVE: This article provides an overview of tactile displays. Its goal is to assist human factors practitioners in deciding when and how to employ the sense of touch for the purpose of information representation. The article also identifies important research needs in this area. BACKGROUND: First attempts to utilize the sense of touch as a medium for communication date back to the late 1950s. For the next 35 years progress in this area was relatively slow, but recent years have seen a surge in the interest and development of tactile displays and the integration of tactile signals in multimodal interfaces. A thorough understanding of the properties of this sensory channel and its interaction with other modalities is needed to ensure the effective and robust use of tactile displays. METHODS: First, an overview of vibrotactile perception is provided. Next, the design of tactile displays is discussed with respect to available technologies. The potential benefit of including tactile cues in multimodal interfaces is discussed. Finally, research needs in the area of tactile information presentation are highlighted. RESULTS: This review provides human factors researchers and interface designers with the requisite knowledge for creating effective tactile interfaces. It describes both potential benefits and limitations of this approach to information presentation. CONCLUSION: The sense of touch represents a promising means of supporting communication and coordination in human-human and human-machine systems. APPLICATION: Tactile interfaces can support numerous functions, including spatial orientation and guidance, attention management, and sensory substitution, in a wide range of domains.     

安阳炉卷新增2号加热炉接口设计及调试

在基础自动化系统中,不同系统间的网络通讯和接口是很重要的内容,特别是对于改造项目,需要考虑和解决的问题更复杂。安钢炉卷新增2号加热炉工程是一个典型的例子,既要考虑不同系统间通讯的技术问题,还要考虑调试和生产的关系问题。本文以此为例,介绍了处理这方面问题的经验。     

Conditional copulas, association measures and their applications

One way to model a dependence structure is through the copula function which is a mean to capture the dependence structure in the joint distribution of variables. Association measures such as Kendall’s tau or Spearman’s rho can be expressed as functionals of the copula. The dependence structure between two variables can be highly influenced by a covariate, and it is of real interest to know how this dependence structure changes with the value taken by the covariate. This motivates the need for introducing conditional copulas, and the associated conditional Kendall’s tau and Spearman’s rho association measures. After the introduction and motivation of these concepts, two nonparametric estimators for a conditional copula are proposed and discussed. Then nonparametric estimates for the conditional association measures are derived. A key issue is that these measures are now looked at as functions in the covariate. The performances of all estimators are investigated via a simulation study which also includes a data-driven algorithm for choosing the smoothing parameters. The usefulness of the methods is illustrated on two real data examples.     

堆芯核测数据采集系统改造的设计与调试

介绍了秦山核电有限公司堆芯核测数据采集系统改造项目的系统设计与调试,叙述了秦山核电有限公司堆芯核测系统的原理,对改造的原因、范围、主要阶段做了简单的描述,重点介绍了系统的设计和调试,对调试过程中出现的问题及解决过程做了详细的分析。     

CPLD在基于单片机的多入多出控制系统中的应用

本文介绍了一种CPLD芯片在基于单片机控制的多入多出系统中的应用,详细说明了根据实际新型按摩浴缸需求进行CPLD芯片设计的方法,主要突出了CPLD在特定应用下的灵活性、易用性,最后给出了所设计CPLD芯片的实际应用效果。     

Development and applications of an interactive digital filter design program

We have implemented an interactive digital filter design program in the HP 1000 computer at the Department of Electrical Engineering of the University of Washington. This program allows users to design different types of filters interactively with both amplitude and phase responses displayed on graphic devices. The performance of each designed filter can be evaluated conveniently before the best one is chosen and implemented for any particular application. This program can design recursive filters, e.g. Butterworth, Chebyshev and elliptic, or nonrecursive filters with one out of six different windows, i.e. rectangular, triangular, Hann, Hamming, Blackman and Kaiser. The main outputs from this program are coefficients of a transfer function of an analog filter, a digital filter, or both. Therefore, the design of both analog and digital filters is facilitated by using this program. The program is very simple to use and does not require background in analog or digital filter principles in order to run it. The program is written in standard FORTRAN and is about 30 kbytes in size excluding the graphics display routines. Since it uses standard FORTRAN, it can be easily transported to minicomputer and microcomputer systems that have a FORTRAN compiler and minimal graphics capabilities. This program is available for distribution to interested institutions and laboratories.     

Decomposition schemes and acceleration techniques in application to production–assembly–distribution system design

The purpose of this paper is to study several schemes for applying Dantzig–Wolfe decomposition (DWD) to the production–assembly–distribution system design problem (PADS). Each scheme exploits selected embedded structures. The research objective is to enhance the rate of DWD convergence in application to PADS through formulating a rationale for decomposition by analyzing potential schemes, adopting acceleration techniques, and assessing the impacts of schemes and techniques computationally. Test results provide insights that may be relevant to other applications of DWD.     

High or low resolution? conflicts of accuracy,cost, quality,and application in computer mapping

The advent of microcomputer mapping has led to a large number of claims as to its general utility in computer mapping. While discussions take place about high- or low-resolution displays, more fundamental aspects of spatial information processing are being obscured. This paper considers the nature of spatial information in a digital environment and examines institutional and professional influences which impinge upon development.     

Linear fuzzy clustering techniques with missing values and their application to local principal component analysis

In this paper, we propose two methods for partitioning an incomplete data set with missing values into several linear fuzzy clusters by extracting local principal components. One is an extension of fuzzy c-varieties clustering that can be regarded as the algorithm for the local principal component analysis of fuzzy covariance matrices. The other is a simultaneous application of fuzzy clustering and principal component analysis of fuzzy correlation matrices. Both methods estimate prototypes ignoring only missing values and they need no preprocessing of data such as the elimination of samples with missing values or the imputation of missing elements. Numerical examples show that the methods provide useful tools for interpretation of the local structures of a database.