An interactive electronic book approach for teaching computer implementation of industrial control systems

There is an overall consensus on the importance of laboratory work that exposes the students to broader and more practical issues of industrial control systems, such as their implementation by distributed computer systems (DCSs) and programmable logic controllers (PLCs). However, setting up appropriate laboratory facilities to serve this purpose is expensive. For this reason, an interactive learning environment has been developed around the concept of the electronic book. The architecture of the environment allows the integration of hypertext with simulators of DCS, PLC, and process operation. The simulators are specially designed to serve an application-oriented teaching approach, which involves the student in the simulation setup and the running of the application. They are able to simulate not only the execution of the software that realizes the regulatory control algorithms but also the start-up and emergency control strategies of an industrial process, the manual, automatic, and cascade modes of controller operation, and the man-machine interface of a DCS- or PLC-based control system. The applications on which the teaching of DCS and PLC-based control system implementation is based are the interactive advanced control of a distillation column and the pH control of a reactor solution.     

The case for assembly language programming

A successful educational course on assembly language programming at the University of Illinois is described with particular emphasis on its pedagogical innovations, including the treatment of multitasking and the provision of library versions of subroutines. The course reinforces fundamental concepts of both data and control structures by illustrating their machine-level implementations. The machine problems provide experience with the design of large programs and with real-time data acquisition and control graphic devices     

Introducing DSP with an electronic book in a computer classroom

A first course in digital signal processing is being taught with an electronic book in a computer classroom. The electronic book is a set of Mathcad documents bound with hyperlinks and with navigation, full text search, annotation, and special pasting facilities. The documents consist of interactive text, graphics, and mathematics regions. The computer classroom consists of 20 student personal computer (PC) workstations and an instructor's podium with PC workstation, lighting, and projection (computer screen, overhead, and video) controls. The electronic book, the computer classroom, experience with student-selected content and pacing, portfolio and project evaluation, and other instructional methods are discussed     

Sinusoidal current‐tracking control for utility interactive inverter with an LCL filter

A voltage source inverter with an LCL filter is often used for a utility interface to control its output current to a grid side because of its harmonic reduction advantages. The integral compensator is often used to reduce the steady‐state errors. However, there is always a control delay due to sinusoidal variations. This paper proposes a digital sinusoidal compensator which is based on the internal model principle to realize a fast sinusoidal response with no delay. It is based on the internal model principle to realize a response with no deviation for a periodic sinusoidal reference input. It has a simple numerator and a denominator z² ? 2z cosωT + 1 of a transfer function which is equal to the z function of a sinusoidal waveform of the angular frequency ω and the sample time T. Compensator and feedback gains of the inverter are determined by the deadbeat or the optimal control principle. The proposed method is investigated for performances and it is validated through simulation and experimental results by a DSP control system. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 183(2): 22–28, 2013; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.22339     

不确定性环境下园区风光储互动运行的PPO强化学习策略

随着能源结构的不断升级,部署有新能源发电的新型园区将在未来新型电力系统中扮演重要的角色。需求的随机性、风光出力的间歇性、电力市场电价的波动性等不确定性因素耦合在一起,使得风光能源与电池储能系统的合理互动运行变得十分困难。考虑到传统优化方法的局限性,提出了一种基于PPO算法的深度强化学习方法,用于解决不确定环境下园区风光储互动运行问题。基于强化学习的理论框架,为园区互动运行构建了一个具有连续状态空间和连续动作空间且转移概率未知的马尔可夫决策模型,通过与新型负荷控制系统对接的能源管理系统控制园区微电网中的电池储能系统及柔性资源,在充分考虑电池退化成本的基础上,实现园区经济运行。     

An automated learning system for Java programming

The increase in the numbers enrolling in university computer courses makes huge demands on resources, and maintaining standards of teaching and tutorial support is almost impossible without a massive increase in staff. To overcome this situation, the authors have developed RoboProf, an automated learning environment which, as well as generating and assessing programming exercises, provides ongoing assistance and feedback to students without extra demands on lecturer and tutors' time. This system also contains a technique for detecting plagiarism, an increasing problem in computing courses worldwide. For this research, RoboProf was used to teach Java programming to a class containing nearly 300 students in the first year of a computing degree. Use of the system by students was monitored and recorded on log files in order to investigate the extent to which usage patterns influence achieved programming skill. An analysis shows that students who complete the set of RoboProf exercises perform significantly better than those who do not. The timeliness in which these exercises are completed relative to other students is significant: early solvers get higher marks, and students solving the problems with fewer attempts get higher marks. Not surprisingly, plagiarists achieve a lower score than those who do their own work. Other factors that were found to influence programming performance included entry standards and gender. Entry qualifications impacted positively on performance, and males performed significantly better than females. There was a significant positive correlation between the score achieved in the RoboProf course and the performance in a subsequent computing course administered in the traditional manner.     

A programming learning system for beginners-a completion strategyapproach

The purpose of this research is to develop a programming learning system for beginners using the completion strategy. The completion strategy uses well-designed programs to let students engage in completing, modifying, and extending their programs. The completion strategy is a paradigm of learning by examples with learning enforcement. In this paper, learning theories of the completion strategy are investigated. A template technique is employed to realize the strategy. An educational experiment was made to show the learning impact of the proposed system. The experimental result shows that the completion strategy is benefit to the programming learning for beginners     

用C语言调用汇编语言的方法与实现

<正> 近年来,C语言作为当今最流行的程序设计语言,已经越来越受到计算机工程技术人员的青睐。它兼顾了多种高级语言的特点,具有处理功能强、使用灵活、有良好的移植性。而汇编语言则是计算机能提供给用户的最快而又最有效的语言,也是能够利用计算机所有硬件特性并能直接控制硬件的唯一语言。因而在对于程序的空间和时间要求很高的场合,汇编语言是必不可少的;而对于需要直接存取、控制硬件的应用场合,则更是非汇编语言莫属。     

Java-based distance learning environment for electronic instruments

Computer-assisted instruction has been used to assist both teachers and students. Recently, the rapid emergence of the World Wide Web (WWW) and its associated tools have provided educators with an opportunity to incorporate this technology into their courses. The undergraduate students in the Mechanical Engineering Department utilize electronic instruments or mechanical instruments frequently. They learn how to use these instruments primarily through a teacher's oral instructions and demonstration. In this paper, the authors developed a computer-aided instruction (CAI) system consisting of four modules: information module, instrument module, examination module, and frequently asked question (FAQ) module. These four modules were arranged to implement a CAI system for electronic instruments. This system is used to teach students how to use oscilloscopes, function generators, and logic analyzers. The CAI system can be used for distance learning.     

Fuel restricted short term economic dispatch using evolutionary programming for utility system

The objective of the paper is to minimize the production cost of the thermal power generation. An elegant approach is presented in order to obtain the equivalent cost function of the participating non-fuel restricted units and the Economic Dispatch Calculations (EDC) are carried out along with fuel restricted units. The Evolutionary Programming (EP) technique is used for real power optimization with fuel restricted units. The optimal solution is obtained neglecting losses. The Fast Decoupled Load Flow (FDLF) analysis is conducted to find the losses by substituting the generation values. Then the loss is participated among all generating units using participation factor method. The load flow is conducted again and the voltage limit violation is checked. The Algorithm is tested on IEEE 6-bus system IEEE 30-bus system and a 66-bus utility system. The results obtained by this new approach are compared with those obtained using classical method. It is observed that the proposed method is more reliable and efficient.     

Development of an interactive CDROM-based tutorial for teachingMATLAB

This paper describes the development of an interactive computer-based tutorial for MATLAB. This tutorial has been developed for undergraduate or graduate students who have had little or no exposure to MATLAB. Students are guided through new concepts and syntax with useful aids such as audio, video and interactive exercises. The exercises, implemented in a specially designed exercise window, give the students an opportunity to use MATLAB to solve problems immediately after covering new concepts. The exercise window has a background interface to MATLAB and thus all commands entered in the window are executed by MATLAB. Hints, example solutions, multiple choice quizzes and test problems, requiring the use of proper MATLAB structure and syntax, add to the learning experience. This project was initially undertaken to investigate student response to alternate computer-based teaching methods. Thus student input has played an important part in the development of this tutorial. Subjective feedback from students, which is presented in the paper, indicate great promise for this alternate approach to teaching MATLAB     

Autoconnected-electronic-transformer-based multipulse rectifiersfor utility interface of power electronic systems

In this paper, an autoconnected electronic transformer (ACET) for 12- and 24-pulse rectifier systems is proposed. Considerable reduction in size and weight is achieved by operating the transformer core at a higher frequency. The rating of the autotransformer is a fraction of the output power. Utility line currents are multipulse in nature with the cancellation of several lower order harmonic currents. Furthermore, the magnetic components on the rectifier DC side are also exposed to higher frequency and can be reduced in size and weight. With an operating frequency of 990 Hz and utilizing conventional grain-oriented steel, a size reduction of 1/3 is achieved compared to a conventional 60 Hz design. Finer grades of steel or alternatives, such as amorphous material, would increase the performance advantage even further. Another unique feature of the proposed concept is that the switching frequency components are neutralized at the input side of the rectifier system. A second configuration using an open delta ACET is also presented. The proposed concept is suitable for higher power rectifier systems, which demand clean input power characteristics. This paper presents analysis, simulations, design example and experimental results for a 208 V 10 kVA prototype system     

A suitable single-phase pulse width modulation current source inverter for utility interactive photovoltaic generation system

A suitable single-phase inverter for the utility interactive photovoltaic generation system is proposed. The single-phase Pulse Width Modulation (PWM) current source inverter has a novel circuit configuration in which an auxiliary branch is added to the normal single-phase bridge circuit. To reduce the size and weight of the dc reactor, a double frequency parallel resonance circuit (LC tank circuit) is inserted in the dc side of the inverter. As a result, the double frequency voltage appearing in the dc side of the inverter due to the pulsation of the single-phase instantaneous power is perfectly suppressed by the tank circuit. The constant dc current without pulsation is supplied from PV array to the inverter. The inverter provides a sinusoidal ac current for domestic loads and the utility line with unity power factor. The virtual maximum power of the PV array can be obtained without any feedback control. In the system, the PV array can play an important role as a current-limiter due to its V-I characteristics. Computed waveforms by simulation are shown. Excellent inverter equipment will be realized that is smaller in size and lighter in weight than is usual for a conventional inverter.     

Educational Applets for active learning in properties of electronic materials

The traditional lecturer-driven classroom is giving way to a new more active environment, where students have access to a variety of multimedia course materials. The authors created several Java applets (http://www.collage.soe.ucsc.edu) that present concepts related to properties of materials in both active and passive styles. The authors evaluated the use of the applets in a classroom setting, considering student learning preferences, background profiles, and applet preferences.     

Emulation of the occam(TM) parallel programming language

This paper describes emulation of parallel execution of a program written in standard occam^(TM) source code. The occam language is a high-level language specifically designed to accommodate concurrent programming. The emulator checks and executes most instructions in the occam 2 language, providing a useful tool for debugging simple occam programs, and also provides accessibility to allow monitoring of execution. A “user friendly” graphical interface is an integral part of the emulator. The paper describes the emulator and its use in teaching the occam language and parallel programming concepts to final year undergraduates. The teaching context is given and laboratory notes outlined along with sample programs that illustrate features of the language     

某装备外场交互检修设备设计与实现

某机载信息装备体积大、结构复杂,针对其外场快速维修保障需求,设计了外场交互检修设备.基于系统综合集成技术,搭建了便携式辅助维修测试硬件平台,包括便捷式维修辅助设备(PMA)平台和外场原位测试设备两部分.平台读取BIT数据,并利用总线控制外场原位测试设备进行参数采集;开发了交互式电子手册,实现了资料查询、代码下载、电子履历和数据同步等功能.应用表明,设备稳定可靠,性能指标满足该装备原位检测和外场故障诊断需求,提高了维修保障效率.     

Algorithm tuners for PSO methods and genetic programming techniques for learning tuning rules

In recent years, improvements in processing power have allowed the application of optimization methods to complicated large optimization problems. Among these methods, heuristic optimization techniques such as particle swarm optimization (PSO) have been a particular focus of attention because of their simplicity, performance, and easy software implementation. However, there is no solid theoretical foundation for analyzing the convergence of these algorithms, and in practice, their rate of convergence is often determined by the choice of parameters. For this reason, the algorithm's parameters must be tuned appropriately for each new optimization problem we want to solve, and in some cases the parameters must be varied as the algorithm is updated. In this paper, we combine a feedback element as an algorithm tuner with an original algorithm; the resulting algorithm is applied to the optimization problem in question, and we use genetic programming (GP) to generate tuning rules to automatically tune the algorithm, according to its current state, as the algorithm is updated. More specifically, we adopt PSO as a heuristic optimization method, and we augment PSO by using GP as a meta‐algorithm to solve the learning problem of automatically generating tuning rules for the parameters in the PSO algorithm. This leads to the proposed method for generating parameter tuning rules to solve optimization problems more efficiently. © 2014 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

A control scheme for a three‐phase current source inverter in utility interactive photovoltaic system

A novel PWM control scheme for a three‐phase current source inverter of a photovoltaic (PV) generation system connected to a utility is proposed. The PV‐array output power can be adjusted by controlling the modulation factor in the proposed PWM pattern. The harmonic components of the output currents can be decreased sufficiently to satisfy the requirements of the Interactive Guidelines. Furthermore, a new Maximum Power Point Tracking control is proposed. The inverter output current should be detected, and the modulation factor may be controlled so as to obtain the maximum effective current. The inverter output power can be maintained at the maximum power point despite fluctuations of panel temperatures, insolation levels, and system voltages. © 2001 Scripta Technica, Electr Eng Jpn, 135(1): 43–55, 2001     

A novel strategy for a high‐power utility interactive inverter with a series active filter

High‐power utility interactive inverters used for large‐capacity energy storage systems are composed of multiple connected inverters, in order to realize high efficiency and high performance of the harmonic elimination characteristic simultaneously. Some disadvantages of multiple connected inverters, such as harmonic current flowing from an inverter unit to the other one, and increase of the number of inverter units, cannot be overcome easily. This paper presents a novel strategy for a high‐power utility interactive inverter, which is composed of a large power with low‐switching‐frequency PWM inverter (high‐power PWM inverter), an LC passive filter, and a series active filter (series AF). Because harmonic components contained in the utility line current are absorbed by the series AF, the switching frequency of the PWM inverter can be selected to about 1 kHz. In addition because the power capacity and the output voltage of the series AF can be suppressed lower than 10% of the power capacity and the output voltage of PWM inverter, low‐voltage and high‐speed power devices can be applied to the series AF. Consequently, high power, high efficiency, and high harmonics elimination performance can be realized without increasing the number of inverter units. © 2002 Wiley Periodicals, Inc. Electr Eng Jpn, 141(2): 57–66, 2002; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10048