The power-supply of X-ray machine adopting PID control and high-frequency inverter technology

To solve the problem of low control accuracy and low stability of current X-ray machines, a kind of digital power supply for X-ray machine is introduced. In the digital power supply, some key technologies are used to improve the output stability of the high frequency inverter, including improved BUCK circuit for voltage regulating circuit, high frequency inverter and soft switching technology for the high-voltage generator. The PWM control technology is used to control the switch transistor of voltage regulating circuit and inverter circuit, which makes the drive waveform output stable and easy to control. In order to improve the control accuracy, reduce the volume and change high voltage consecutively, the software PID of the microcomputer is used to control the feedback circuit. The high-accuracy power chip is used for the filament power supply to make the filament electric current stable. Through the analysis of the circuit, the parameters of the circuit are calculated and the circuit is simulated by PSPICE software. The results show that the theoretical analysis is consistent with the practical simulation results. The design can meet the requirement of the technology indices of the power supply of the X-ray machines.     

A power distributed computing system model based on services-oriented architecture

Process communication based power distributed computing model satisfies the demand on real time monitoring and analysis for the economical operation of power grid based on power distributed computation methods, but there are some problems on complexity in common basic functions development and lack of system extendibility. An extendable services-oriented power distributed computation system model is designed and implemented. Software design patterns are applied to design low coupling and extendable system framework. Windows Communication Foundation (WCF) technology is used to implement the services-oriented distributed data communication functions. Windows Workflow Foundation (WWF) technology is used to design the business logic of power distributed computation visually. Data integration functions are implemented by combining the ADO.NET technology. The services-oriented system architecture enhances the integration ability and extendibility. The use of WCF and WWF technology reduces the complexity of the system development.     

农业双向视频诊断系统的设计与研究

农业信息化服务是实现中国农业现代化的重要手段。随着基于3G的多路音频视频传输技术的逐渐成长、完善,迫切需要满足农业技术交流的音视频通信工具和远程专家诊断系统。笔者利用开源的Open Meetings系统进行设计和二次开发,实现了农户、农技员与专家之间的远程视频交流,并将该系统应用于全国基层农技推广信息化平台,为服务三农及农业信息化提供了有力的支持。系统实施后的实际的效果表明,该系统有效地促进了新技术的推广和信息资源的整合。     

一种基于PLC的高速远程控制果蔬智能分选技术研究

果蔬分选是农业果蔬产后不可缺少的重要环节,以可编程逻辑控制技术为核心的自动化生产线为现代农业的智能化发展提供了新途径.为提高果蔬的分选效率,减少本地分选的人工成本,将数据采集、数据处理、无线通讯、智能控制等技术深度融合,研究一种可远程控制的果蔬智能分选机制,并通过可编程逻辑控制器(PLC)自动化数据采集与机械控制和.NET Core架构的分布式网络控制方法两方面对远程控制分选方案进行研究,配合合适的糖度-质量等果蔬品质模型,实现高速远程在线果蔬智能分选.基于该分选技术的软硬件方案进行试验,对控制策略和分选精确度进行仿真.结果表明,与传统的果蔬分选技术相比,该系统从系统成本、反应速度、分拣精度、管理效率等方面均有优势,果蔬分选精度能达93％以上,可以实现远程故障排查,节省了人工成本,具有推广应用价值.     

基于无线传感器网络的鱼塘监控系统

本文设计了基于无线传感器网络的鱼塘实时在线智能监控系统,有效解决了传统的鱼塘观测手段存在的问题,例如：费时费力、步骤复杂、成本高等。该系统在鱼塘的监测区域中利用无线传感器节点,测得该区域中的温度和溶氧量,并通过Zigbee网络将数据传输到终端控制系统,控制系统作出判断并发出报警信号和控制增氧机的状态。系统中以MSP430和XBEE模块为核心芯片,能够实时在线监测鱼塘中的一些参数,例如温度、溶氧量等。同时该系统还可以进一步扩展使用GPRS或3G网络实现远程监控。     

Remote Test Method of Relay Protection

Considering the limitation of the field test for relay protection in power system, the paper studies and discusses the remote test method of relay protection in power system. It provides the technology requirements, the technology problems and restricted factors to build the protection test and analysis center. It proposes the method of building the protection test and analysis center. Considering the practice for the transmission of test data, the paper introduces the technology requirements of utilizing dispatching automation system data network to transmit the protection test data. Considering the requirements of microcomputer protection devices for remote test method, the paper presents that there are remote test function and synchronization test function in the field microcomputer protection devices.     

基于物联网的集成化粮食供应链管理研究

摘要：本文首先依托物联网技术及网络对粮食供应链进行优化,根据“拉式”供应链理论集成现代物流及供应链功能,利用信息技术集成粮食供应链涉及的企业及粮食流通环节,然后基于射频识别技术构建集成化粮食供应链模型及整体架构,依托射频技术提供的大量数据及处理能力进行计算求解,获得精确的预测,在物联网的支撑下研究集成化粮食供应链的管理。研究构建粮食及其加工品的质量跟踪、控制及追溯,确保粮食及其加工品的食用安全;依据物联网技术支持下集成化粮食供应链管理信息系统的精确预测,建立粮食供需安全预警系统;通过基于物联网对粮食供应链进行集成化管理,降低粮食及其加工品物流费用,提高流通效率及效益。     

Hybrid Power Supply Based on One Cycle Control

A hybrid power supply is composed by both a linear and a switching source connected in parallel and it can improve the dynamic response. But the hybrid power supply cant not effectively reject the perturbations in the power supply. A hybrid power supply based on one cycle control theory is proposed in order to improve the capability and the control precision. A switching source based on one cycle control is adopted in the hybrid power supply. The analysis results indicate that the hybrid power supply can effectively reject the perturbations in the power supply. And the analysis results also show that not only the control precision is improved, but also the control circuit is simple. The simulation resuits given verify the correctness and effectiveness of the proposed method.     

Serial Communication System Between PC and PLC Based on Visual C++

It is usually need to supervise and control gathering data and working status of PLC in industry control.There are some ways such as VB,DELPHI,PB to carry out the requirement.Visual C++ is an exploiture tool for Windows application program and has quite strong function in the aspect of image processing and database managing etc.It has faster speed to realize bottom communication control.Using Visual C++ and MFC,the authors implement the serial communication system between PC and PLC.The paper introduces the communication protocol and software design method and realizes data's sending and incepted rapidly,real-time auto-control accurately and quickly.This system is simple,economical,and reliable and has an application value,which has been applied successfully in real system.     

基于嵌入式Linux-ARM的储粮监测技术的研究

设计了一个基于ARM技术的粮库嵌入式监测系统.该监测设备由两部分结构组成:一个是上位机电脑控制端对粮食信息的监测和处理,另一个是在下位机实现对粮仓粮食数据的采集,信号的处理以及通讯的功能.通过工业以太网或GPRS网络可以将数据从一方传给另一方.在此基础上展开以S3C2410处理器来实现粮食相关信息监测的研究,其中人机交互界面终端通过Qt/E来设计.试验测试结果证明了该系统的可靠性和稳定性.     

Fuzzy PID Power Adjustment of Computer Monitor and Control System for Hydropower Station

The computer monitor and control system for hydropower station is always a structure system of laminate distribution and open style. The system can adjudge active power and inactive power of water turbine according to the requirement. The operators in active-control level give the value of active power and inactive power for water turbine by computer workstation. PLC of LCU run the power control procedure by net communication in order to realize power adjust. The power adjust of water turbine mainly by speed control system and magnetization system. The 2-D Fuzzy PID Control Model is proposed in order to carry out power adjust of water turbine . In this new method the parameter of PID can self-neaten on line according to power deviation and power deviation rate. By means of this procedure the machine unit can obtain given power value rapidly, exactly and stably. It can make the power adjust of monitor and control system obtain good control characteristic and robust, and it is benefit to extend the work life of machine unit.     

Application of Web Service in Remote Report Printing System

Aiming to the problems in designing report under B/S pattern condition the paper presents, a kind of remote report solution based on Web Service. It also presents the system design principle and reviews the related technology of Web Service. The key technology of specific implement to remote report-printing system based on Web Service is presented at last.     

基于双模定位的冷链物流实时监测系统

为加强冷链物流监管,实现冷链物流的全程温度和定位监测,设计了基于双模定位的冷链物流实时监测系统。本系统除了集成嵌入式技术、卫星定位技术和GPRS无线通信技术等以实现温度采集、数据远程传输和定位等功能,还使用融合数据的双模定位取代单GPS定位以提高复杂环境下的定位精度,并提出使用改进的扩展卡尔曼滤波算法进行定位解算以实现双系统下定位数据融合,在静态时对水平精度和三维精度分别提高了37.5%和28.6%。测试结果表明,本系统提高了冷链物流监测能力,为未来研究冷链无人配送的定位问题提供基础。     

基于机器学习与高光谱数据的湿地植被物种识别研究

为了探索利用高光谱高空间分辨率遥感数据进行湿地植被物种识别，笔者在分析6 种湿地植被原反射光谱、二阶微分及连续统去除光谱的基础上，利用马氏距离法和相关系数法提取特征波段，并将其作为特征参数参与C5.0 决策树分类与信息提取。结果显示：（1）基于机器学习的C5.0 决策树法总体分类精度为79.87%，Kappa 系数为0.765，与监督分类最大似然法相比，植被信息提取总体精度提高9.95%，Kappa系数提高0.114；（2）机器学习C5.0 决策树法与最大似然法相比，其独特的优势在于对藻类的信息提取精度大大提升，狐尾藻和水蕴草的用户精度提升最大，分别提升了18.67%和15.86%。该方法能够实现湿地植被物种信息的高精度提取，为同类研究提供借鉴，为湿地生态健康评价提供科学与技术上的支持。     

Research and Development of the Network Virtual Instrument

This paper introduces a basic concept of network virtual instrument and presents a solving scheme based on the .net framework for web network virtual instrument in which the component technology are used to construct UI component, data-service component, signal-processing component, DB-component, controlling component and data-acquiring component, in accordance to demand these component above can be flexibly put on the right place to realize remote test and control. In the light of the scheme, a set of network oscilloscope based on web is designed to remotely sampling data, and the technology of data base is successfully used to administer the saving and taking of signals in network virtual instrument .     

Twisted Blade Virtual Design for Steam Turbine

Due to lack of estimation during initial stage of traditional physical design process for industry product, the efficiency of conduct development is low with high cost. A basic framework of twisted blade virtual design is set up based on the theory and method of product virtual design, and aiming at the thermodynamic process of middle or lower stage of steam turbine. The molding rule of twisted blade is found by thermodynamic computation program. The study of blade virtual design is carried through from 3-dimensional modeling to simulation test. The combination of thermal power theory, computer simulation technology and CAD system forms a kind of design method with the superiority such as high efficiency, low cost and good decidability is represented in the virtual design of turbine blade.     

Hidden Dangers on Linkage Control of Electrical Devices and Design Installation and Debugging of Power Supply and Distribution Underground Space

Linkage control of fire-fighting electrical equipment effectively and reasonable design, installation and debugging of power supply and distribution are increasingly important to ensure the safety of underground space. As the linkage control systems associated with the fire control electrical equipment are very complicated, and the distribution of installation and debugging are very professional, there are many hidden troubles of safety in the whole life cycle process. On the basis of analysis of characteristics of underground space of fire, underground fire-fighting electrical equipment and the requirement of power supply system are expounded, hidden dangers on linkage control of electrical devices and design installation and debugging of power supply and distribution underground space are analyzed, and some suggestions and countermeasures are provided for relevant departments as decision-making reference.     

Design of Information Terminal in the Water Supply Industry

A information terminal is designed , which is applied to administration and service management in the water supply industry of city. The situation of administration, service management and demand of reform about tradition technology are researched. Combining the advantages of information-processing and movable operation of the pocket PC, a communication model of terminal which can collect data in the field and a processing software are developed . It has the characteristics such as acquisitioning data , service , management, movable operation to traditional water meters, smart card water meters and remote water meters. It has been applied to housing estate and water supply industry at present ,with the widely used ,it improves the situation of management in the water supply .     

管控一体化在粮库中的应用

管控一体化是控制领域中的一个热门技术。在信息、电子、通讯、控制等技术的快速推动下，管理网络和控制网络的一体化技术取得了长足进步，管控一体化在工业控制系统中的应用也十分广泛。本文以中央储备粮赤壁直属库为例，介绍了直属库管理监控系。统的总体设计和具体实现，展现了一种结合Internet、Intranet和Infranet的应用模式。     

山东省农情遥感监测平台构建研究

[目的]准确及时的农情信息是各级政府制定农业政策、管理指导农业生产的重要依据。遥感技术在山东省农业资源调查、农情监测、灾害预警等领域发挥着越来越重要的作用,亟需建立一个服务于农业生产管理需求的省级农情遥感监测业务化运行平台。[方法]利用地理信息系统（GIS）、遥感技术(RS)和网络技术,基于MapGIS平台,提出了山东省农情遥感监测平台建设的重要意义、设计原则、总体架构、建设内容以及系统的总体部署。[结果]平台的建立,将实现山东省主要粮食作物面积、长势、产量、灾害等农情信息的动态监测与及时发布,同时为公众提供专题遥感监测产品服务。[结论]推动农情遥感监测的广泛应用和产业化发展,为保障粮食安全、强化农业生产科学管理和建设现代农业提供强大的支撑。