大型生活垃圾中转站设备及作业流程改进分析

大型生活垃圾中转站是城市垃圾处理的枢纽,其设备组成以及作业流程是高效完成垃圾压缩中转工作的重要前提。大型垃圾中转站设备主要由检查计量设备、进料设备、压装设备、除尘除臭设备、污水处理设备、自动控制设备、运输设备等组成,各组设备相互联系共同完成进料、压缩装箱、转运等流程阶段。     

VertexRSI地球站伺服系统

卫星通信地球站组成卫星通信地球站主要由:天线、射频设备、终端设备、天线跟踪伺服设备、电源设备组成。跟踪伺服设备的作用由于卫星的漂移、大气折射等原因,天线的指向常常偏离理论方向,而地球站天线波束一般较窄,因而真正在     

多媒体教学设备故障判断及维护

随着多媒体技术的不断发展,使黑板加粉笔的教学模式进入到多媒体教学时代,多媒体教学设备是由多种设备的综合组成,主要包括计算机设备、投影仪、实物展示台等软硬件组成。如果在教学过程中,某一设备出了问题,会影响正常的教学工作。本文根据本人多年来的多媒体管理和维护经验,谈一谈多媒体设备的故障判断及维护、维修方法。     

JC-3196测试系统检修分析

在设备维修中分析的过程就是查找故障的过程,因此设备维修的关键就是懂得对设备故障如何进行分析,但是要想准确的对设备故障进行分析,就必须详细了解设备的硬件组成及各部分的工作原理。因此文章从简单介绍JC-3196测试系统的硬件组成及各部分的工作原理开始,然后再介绍几种设备常见故障,并通过这些故障的现象对其进行详细的检修分析。文章从四个方面对其进行说明:JC-3196测试系统的硬件组成、各部分源的主要功能及工作方式、故障分析、维修的注意事项。     

ADSL接入技术(2)

主要描述了组成ADSL系统的局端设备、用户设备和分离器。     

中波发射台发射机音频前段系统的应用探析

中波广播数字调幅发射机音频前端设备由很多繁杂的部件组成,包括光纤接收机、调频接收机、平衡转换器、切换器、分配器等等很多设备组成。其中有部分设备在整个系统中发挥着非常重要的作用。为了加深相关工作人员对这些设备的了解,本人组织了这篇文章的撰写,主要就接收设备、音频增益调节器、音频切换器、音频处理器以及音频分配器这五个重要部件的应用进行了研究,希望相关工作人员看过后能够有所裨益。     

一种实用的电声设备:多功能舞台监督工作台

一、前言为适应我国舞台监督工作发展的需要,我们开发研制了一种多功能舞台监督工作台。它具有多路音频信号转换、灯光联络、有线电话通信与电视监视等功能,是一种新型的舞台监督控制设备。现场运行表明,性能稳定可靠,用户反映良好。现将本设备的组成、功能、工作原理与主要技术指标介绍如下。二、设备的组成与功能本设备由四部分组成。第一部分是4×16路     

浅谈背景音响系统

背景音响作为音响的新时尚,广泛地应用在娱乐场所。本文浅谈其组成和设备选择。一、组成背景音响系统一般是由声源设备、放大器、控制电路、传输电缆及扬声器等组成。信号的传输方式有声一电直接传输方式和调频、解调传输方式两种。二、设备的选择背景音乐要求信噪比高,频响宽。声源早期采用AM/FM收音头、录音机,但噪声较大,尤其是录音机磁带磨     

恒压供水系统的维护及维修

<正>全自动变频恒压供水系统广泛应用于厂矿、机关等重要场合,具有起动平稳,运行噪声小,供水压力恒定和节能等优点,并可根据用户的需要及对设备保护的要求,对运行中的多台供水设备进行合理、科学、有序地组合轮换,以延长设备的使用寿命。一、设备组成及特点全自动变频恒压供水系统由电源、变频器、水泵、储气罐、供水管道以及各种控制阀门等组成。电源柜作为整套供水设备的电源控制,具备双电源自动切换功能,确保设备的电源供     

卫星直播车使用和保养应该注意的几个问题

本文简要介绍卫星直播车的组成、特点及优点，阐述卫星直播车的设备情况、设备维护和保养。     

A Development Environment for OSA-Based Applications over the Interworked WLAN and Cellular Networks

In this paper, we propose an OSA-based development environment for interworking WLAN and 3G cellular networks. The main goal of our work is to establish and create an environment that can serve as a demonstration of a working network for OSA-based application developers while featuring mobile services over the interworked LAN and 3G cellular networks. The proposed simulating environment has (i) a location update scheme that is used to obtain mobile users' locations and status information over the interworked WLAN and cellular networks, (ii) an instant message gateway (IMG) simulator that is developed to send and receive generic messages over the interworked WLAN and cellular networks, and (iii) a mapping of Parlay APIs onto SIP signaling messages for multiparty call applications over the interworked WLAN and cellular networks. An illustrated OSA-based application that utilizes the corresponding system functions and modules is developed and verified using the proposed simulating environment. Chung-Ming Huang received the B.S. degree in Electrical Engineering from National Taiwan University on 1984/6, and the M.S. and Ph.D. degrees in Computer and Information Science from The Ohio State University on 1987/12 and 1991/6 respectively. He is currently a professor in Department of Computer Science and Information Engineering, National Cheng Kung University, Taiwan, R.O.C. He is the director of The Promotion Center for Network Applications and Services, Innovative Communication Education Project, Ministry of Education, Taiwan, R.O.C. His research interests include broadband Internet and applications, wireless and mobile network protocols, ubiquitous computing and communications, and multimedia streaming. Tz-Heng Hsu received the B.S. degree from Department of Computer Science and Information Engineering, Feng Chia University on 1996/6, and the M.S. degree and Ph.D from Department of Computer Science and Information Engineering, National Cheng Kung University on 1998/7 and 2005/7, Taiwan, R.O.C. He is currently a assistant professor in Department of Computer Science and Information Engineering, Southern Taiwan University of Technology. His research interests are wireless and mobile network protocols, applications over interworked WLAN and cellular networks and communications, and multimedia streaming. Chih-Wen Chao received the B.S. degree from Department of Engineering Science, National Cheng Kung University on 2003/6, and the M.S. degree from Department of Computer Science and Information Engineering, National Cheng Kung University on 2005/7, Taiwan, R.O.C. His research interests are OSA-based applications and distributed multimedia systems.     

Multistandard Analogue Baseband Filters for Software-Defined and Cognitive Radio Receivers

Analogue baseband filters are an important circuit for channel select and anti-aliasing in wireless and mobile communication systems. For software and cognitive radio, they must be widely tunable and reconfigurable to accommodate existing, emerging, and future wireless and mobile standards. In this paper, design considerations of tunable and programmable filters for highly integrated multistandard receivers are presented. General background of multistandard integrated receivers and design challenges of analogue baseband filters are given. Circuit techniques for baseband filter design including the widely used active-RC and Gm-C circuits are described. Filter structures and design methods for high-order baseband filters are reviewed. On-chip tuning issues and methods are discussed. Results and performances of some published design examples are summarized. Future directions are also pointed out.     

基于挑战-应答机制的量子密钥分发协议

基于BB84协议,利用挑战-应答机制,提出了一种量子密钥分发协议。发送方Alice和接收方Bob通过安全信道共享三个不同的Hash函数( , 和 ),以及随机比特串 。在每次密钥分发时,Alice产生随机比特串 （挑战信息）和 （密钥）,结合 和 ,基于BB84协议产生光子串 ;Alice将 和 发送给Bob,Bob接收到对应的 和光子串 ;Bob利用 ,结合 和 ,基于BB84协议对光子串 进行测量得到 。理想情况下共享密钥 。另外,Bob利用 , , 及 产生应答序列 ;Alice和Bob利用各自拥有的序列及 分别产生序列 和 ,并对各自的 做更新。在密钥分发过程中光子的利用率为百分百,该协议既有BB84协议类似的安全性,又有单向身份认证功能。     

Single DDCC Biquads with High Input Impedance and Minimum Number of Passive Elements

Two new configurations for the design of biquad filters with high input impedance are presented. The first configuration can synthesize low-pass and high-pass filter functions according to the passive components used. The second one can synthesize a band-pass filter function. The proposed configurations employ only one differential difference current conveyor (DDCC) as active elements and minimum number of passive elements, namely two resistors and two capacitors. Another filter topology based on DDCC is presented that allows modifying the quality factor without changing its natural frequency. All the filters enjoy low sensitivities. SPICE simulation results are given to confirm the validity of the analysis and to point out the high performance of the filters.Muhammed A. Ibrahim was born in Erbil, Iraq in 1969. He obtained his B.Sc. and M.Sc. degrees from Salahaddin University, Erbil, Iraq and Istanbul Technical University, Istanbul, Turkey in 1990 and 1999, respectively, all in electronics and communication engineering. Between 1992 and 1996 he worked as Research Assistant at Salahaddin University where he was later appointed as Assistant Lecturer in 1999. Since 2000 he has been studying for his Ph.D. degree in Electronics and Communication Engineering Program at Istanbul Technical University. His main research interests are CMOS circuit design, current-mode circuits and analog signal processing applications. He has more than 20 international journal and conference papers in scientific review.H. Hakan Kuntman received his B.Sc., M.Sc. and Ph.D. degrees from Istanbul Technical University in 1974, 1977 and 1982, respectively. In 1974 he joined the Electronics and Communication Engineering Department of Istanbul Technical University. Since 1993 he is a professor of electronics in the same department. His research interest include design of electronic circuits, modeling of electron devices and electronic systems, active filters, design of analog IC topologies. Dr. Kuntman has authored many publications on modelling and simulation of electron devices and electronic circuits for computer-aided design, analog VLSI design and active circuit design. He is the author or the coauthor of 76 journal papers published or accepted for publishing in international journals, 91 conference papers presented or accepted for presentation in international conferences, 99 turkish conference papers presented in national conferences and 10 books related to the above mentioned areas. Furthermore he advised and completed the work of 7 Ph.D. students and 31 M.Sc. students. Currently, he acts as the head of the Electronics and Communication Engineering Department in Istanbul Technical University. Dr. Kuntman is a member of the Chamber of Turkish Electrical Engineers (EMO).Oguzhan Cicekoglu received the B.Sc. and M.Sc. degrees from Bogazici University and the Ph.D. degree from Istanbul Technical University all in Electrical and Electronics Engineering in 1985, 1988 and 1996 respectively. He served as lecturer at the School of Advanced Vocational Studies Electronics Prog. of Bogazici University where he held various administrative positions between 1993 and 1999. He served also as part time lecturer at various institutions. He was with the Biomedical Engineering Institute of the Bogazici University between 1999 and 2001. He is currently Associate Professor at the Electrical and Electronics Engineering Department of the same University.His current research interests include analog circuits, active filters, analog signal processing applications and current-mode circuits. Oguzhan Cicekoglu is the author or co-author of 62 journal papers and about 90 international or local conference papers published or accepted for publishing in journals or conference proceedings.He served as the committee member in various scientific conferences and as reviewer in numerous journals including Analog Integrated Circuits and Signal Processing, IEEE CAS-I, IEEE CAS-II, International Journal of Electronics, Microelectronics Journal, Solid State Electronics and IEE Proceedings Pt.G.Oguzhan Cicekoglu is a member of the IEEE.     

基于MODBUS协议网络的多点火灾测控系统

提出大型测控网络方案,建立基于MODBUS协议的自动测控系统,并通过以太网连接,组建远距离的测控网络;并通过其在火灾测控中的应用,设计了火灾测控预警网络和MODBUS网络系统的电路,制作PCB线路板,进行联网测试,编写了MODBUS协议下的通信程序和上位机火灾监控系统程序,该系统为复杂环境下的火灾预警及测控提供了一定的参考。     

Retinal vascular tree morphology: a semi-automatic quantification

A semi-automatic method to measure and quantify geometrical and topological properties of continuous vascular trees in clinical fundus images is described. Measurements are made from binary images obtained with a previously described segmentation process. The skeletons of the segmented trees are produced by thinning,ff branch and crossing points are identified and segments of the trees are labeled and stored as a chain code. The operator selects a tree to be measured and decides if it is an arterial or venous tree. An automatic process then measures the lengths, areas and angles of the individual segments of the tree. Geometrical data and the connectivity information between branches from continuous retinal vessel trees are tabulated. A number of geometrical properties and topological indexes are derived. Vessel diameters and branching angles are validated against manual measurements and several derived geometrical and topological properties are extracted from red-free fundus images of ten normotensive and ten age- and sex-matched hypertensive subjects and compared with previously reported results.     

雷达通信一体化:共用波形设计和性能边界

很多军事和民用平台都同时具备雷达与通信功能.传统的分立式设计增加了系统的体积、功耗和成本,并降低了系统的电磁兼容性能.雷达通信一体化设计能够让雷达和通信共享硬件平台,从而克服上述缺点,受到了学术界和工业界的广泛关注.总体来看,雷达通信一体化可以通过资源分配和共用波形来实现.共用波形的方式具有更高的频谱效率和功率效率,并...     

一种移动中继拨测系统的设计

设计一种中继拨测系统,模拟MSC交换机、短信SP等设备,通过七号信令与低级信令转接点连接,并与长途汇接局开通直达电路,在核心网上对业务测试和监测,真实地反映网络的质量情况和业务性能,测试表明,该系统加强了业务测试的自动化和规范化,提高了发现和处理问题的能力。从而从提高网络运行性能、改善服务质量、降低成本等多方面为网络运营商创造价值,提高其整体经济效益。     

Web engineering: an introduction

Within a short period, the Internet and World Wide Web have become ubiquitous, surpassing all other technological developments in our history. They've also grown rapidly in their scope and extent of use, significantly affecting all aspects of our lives. Industries such as manufacturing, travel and hospitality, banking, education, and government are Web-enabled to improve and enhance their operations. E-commerce has expanded quickly, cutting across national boundaries. Even traditional legacy information and database systems have migrated to the Web. Advances in wireless technologies and Web-enabled appliances are triggering a new wave of mobile Web applications. As a result, we increasingly depend on a range of Web applications. Now that many of us rely on Web based systems and applications, they need to be reliable and perform well. To build these systems and applications, Web developers need a sound methodology, a disciplined and repeatable process, better development tools, and a set of good guidelines. The emerging field of Web engineering fulfils these needs. It uses scientific, engineering, and management principles and systematic approaches to successfully develop, deploy, and maintain high-quality Web systems and applications. It aims to bring the current chaos in Web based system development under control, minimize risks, and enhance Web site maintainability and quality     

天津网通七号信令集中监测系统

七号信令网是电信网的重要组成部分,其运行质量直接影响到电信网及各种新业务的稳定运行和经济收益。七号信令集中监测系统通过直接采集七号信令的原始数据进行分析处理,提供对七号信令网实时动态监测,以及各种用户信令的各种微观分析。章在分析七号信令集中监测系统框架的基础上,对监测系统的组网结构、系统功能、软件应用做了进一步的研究。