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.     

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.     

Hypercube supercomputers

The architecture and applications of the class of highly parallel distributed-memory multiprocessors based on the hypercube interconnection structure are surveyed. The history of hypercube computers from their conceptual origins in the 1960s to the recent introduction of commercial machines is briefly reviewed. The properties of hypercube graphs relevant to their use in supercomputers, including connectivity, routing, and embedding, are examined. The hardware and software characteristics of current hypercubes are discussed, with emphasis on the unique aspects of their operating systems and programming languages. A sample C program is presented to illustrate the single-code, multiple-data programming style typical of distributed-memory machines in general, and hypercube applications in particular. Two contrasting hypercube applications are presented and analyzed: image processing and branch-and-bound optimization. Current trends are discussed     

Model-based programming of intelligent embedded systems and robotic space explorers

Programming complex embedded systems involves reasoning through intricate system interactions along lengthy paths between sensors, actuators, and control processors. This is a challenging, time-consuming, and error-prone process requiring significant interaction between engineers and software programmers. Furthermore, the resulting code generally lacks modularity and robustness in the presence of failure. Model-based programming addresses these limitations, allowing engineers to program reactive systems by specifying high-level control strategies and by assembling commonsense models of the system hardware and software. In executing a control strategy, model-based executives reason about the models "on the fly," to track system state, diagnose faults, and perform reconfigurations. This paper develops the reactive model-based programming language (RMPL) and its executive, called Titan. RMPL provides the features of synchronous, reactive languages, with the added ability of reading and writing to state variables that are hidden within the physical plant being controlled. Titan executes an RMPL program using extensive component-based declarative models of the plant to track states, analyze anomalous situations, and generate novel control sequences. Within its reactive control loop, Titan employs propositional inference to deduce the system's current and desired states, and it employs model-based reactive planning to move the plant from the current to the desired state.     

An approach to real-time control of robots in task space.Application to control of PUMA 560 without VAL-II

An approach to real-time control is presented that involves the adaption of existing (commercial) hardware and the integration of new hardware and software, such that both feedback control and offline programming using either task or joint-space coordinates are possible. The approach is illustrated in detail through the implementation of a controller that replaces the conventional Victor's assembly language (VAL) II-based controller with the PUMA 560 robot. The controller presents an improvement over the system under VAL in a number of ways, in addition to being able to use either task or joint-space information in the most general form. In particular, the hardware and software of the new controller can accommodate novel sensory systems, robot programming languages, and dynamic models for research and evaluation of advanced control methods     

Software engineering

In this overview of the software engineering industry the following topics are discussed: client server systems; object oriented programming and C++; programming toolkits with application frameworks; and visual programming languages     

Computer architecture for digital signal processing

In this paper, a comprehensive overview of Computer Architecture for Digital Signal Processing is given. Such architectures are seen as the result of constraining influences from the nature of digital signal processing algorithms, architectural techniques including appropriate choice of primitive elements, the underlying digital system technology, and programming languages for digital signal processing. Following a consideration of these influences, several examples are given ranging from chips through board level processors, to attached support processors with very high throughput. Trends for the future are discussed throughout the paper.     

软件进程监控系统及其实现

为了有效地控制软件进程的运行,需要开发一个软件进程监控系统。进行了需求分析,介绍了几种软件开发关键技术,包括软件开机自启动技术、程序运行隐藏技术、进程管理技术和窗口的子类处理技术。针对每种技术都给出了具体的实现方法,并结合以上技术提出了软件进程监控系统的程序设计方案,利用Visual Basic 6.0程序设计语言进行了实现,增强了微机安全管理功能。     

单片机系统多任务实现方法

考虑到成本等因素,大多数单片机系统的开发还是基于处理器直接编写,但开发者经常会面临同时处理多个任务的要求.提出了一种单片机多任务程序设计方法,并以通信设备告警集中监控系统告警指示器(上位机)为例进行了讨论.     

Supercomputers-software on the brink

Prospects for operating systems and languages that will make supercomputers more widely usable are examined. Requirements for supercomputer software and the problems that need to be solved are described. Migration to Unix, which is unifying the operating system environment for supercomputing, is discussed. Languages and dialects are also discussed, and nontraditional languages are considered     

Developing wireless sensor network applications in a virtual environment

We describe our “holistic” platform for developing wireless ad hoc sensor networks and focus on its most representative and essential virtualization component: VUE² (the Virtual Underlay Emulation Engine). Its role is to provide a vehicle for the authoritative emulation of complete networked applications before physically deploying any wireless nodes. The goal is to be able to verify those applications exhaustively before programming the hardware, such that no further (field) tests are necessary. We explain how VUE² achieves this goal owing to several facilitating factors, most notably the powerful programming paradigm that our platform adopts. As implied by the holistic nature of the discussed system, our work touches upon operating systems, simulation, network protocols, real-time systems, and programming methodology.     

Simulation of power electronic and motion control systems-anoverview

This paper presents a users' perspective of simulation in power electronic and motion control systems. The rationale for simulation in research, education and in the design process, and the details of how simulation is carried out are discussed. Characteristics of a reliable simulation program are outlined and the hierarchical approach to simulation is stressed. Numerical solution issues in the simulation of “stiff” systems such as power electronics and motion control are discussed in general terms. A brief overview of the widely used simulation programs is provided along with the challenges in modeling the semiconductor devices. In conclusion, observations are made with respect to the future role and nature of computer simulations     

Scalable parallel computers for real-time signal processing

We assess the state-of-the-art technology in massively parallel processors (MPPs) and their variations in different architectural platforms. Architectural and programming issues are identified in using MPPs for time-critical applications such as adaptive radar signal processing. We review the enabling technologies. These include high-performance CPU chips and system interconnects, distributed memory architectures, and various latency hiding mechanisms. We characterize the concept of scalability in three areas: resources, applications, and technology. Scalable performance attributes are analytically defined. Then we compare MPPs with symmetric multiprocessors (SMPs) and clusters of workstations (COWs). The purpose is to reveal their capabilities, limits, and effectiveness in signal processing. We evaluate the IBM SP2 at MHPCC, the Intel Paragon at SDSC, the Gray T3D at Gray Eagan Center, and the Gray T3E and ASCI TeraFLOP system proposed by Intel. On the software and programming side, we evaluate existing parallel programming environments, including the models, languages, compilers, software tools, and operating systems. Some guidelines for program parallelization are provided. We examine data-parallel, shared-variable, message-passing, and implicit programming models. Communication functions and their performance overhead are discussed. Available software tools and communication libraries are also introduced     

基于支持向量机的克隆代码有害性评价方法

克隆代码是软件中彼此相似的代码片段。传统观点认为克隆代码是有害的，会降低软件质量，但最近研究发现克隆代码不一定是有害的。如何评估克隆代码的有害性是一个值得研究的问题。本文提出了一种基于支持向量机的克隆代码有害性评价方法，可以以较高的准确性和查准率评价其有害性。为验证方法有效性，本文在6个系统上进行实验，结果表明本文方法可以有效地评价克隆代码的有害性，并且所提出的静态度量和演化度量对评价克隆代码有效性具有积极意义。     

A tutorial on protocols

Protocols are common tools for controlling information transfer between computer systems. The concept of a protocol, which grew out of experimental computer networking, is now fundamental to syatem design. In this paper, basic protocol functions are explained and discussed. Then, the concept of a distributed system architecture is presented. It provides the framework for layers and protocols to operate across heterotgeneous systems. The purpose and functions of each protocol layer such as, transmission, transport, virtual terminal, are described. Interactions between design and performance are discussed, and typical mechanisms are reviewed. CCITT and ISO relevant standards are summarized. Finally, the similarity between protocols and programming languages is emphasized as it points to the major impact brought about by protocols in system design.     

Self-Configuring Applications for Heterogeneous Systems: Program Composition and Optimization Using Cognitive Techniques

This paper describes several challenges facing programmers of future edge computing systems, the diverse many-core devices that will soon exemplify commodity mainstream systems. To call attention to programming challenges ahead, this paper focuses on the most complex of such architectures: integrated, power-conserving systems, inherently parallel and heterogeneous, with distributed address spaces. When programming such complex systems, new concerns arise: computation partitioning across functional units, data movement and synchronization, managing a diversity of programming models for different devices, and reusing existing legacy and library software. We observe that many of these challenges are also faced in programming applications for large-scale heterogeneous distributed computing environments, and current solutions as well as future research directions in distributed computing can be adapted to commodity computing environments. Optimization decisions are inherently complex due to large search spaces of possible solutions and the difficulty of predicting performance on increasingly complex architectures. Cognitive techniques are well suited for managing systems of such complexity, citing recent trends of using cognitive techniques for code mapping and optimization support. Combining these, we describe a fundamentally new programming paradigm for complex heterogeneous systems, where programmers design self-configuring applications and the system automates optimization decisions and manages the allocation of heterogeneous resources.