关于飞机液压系统的几个问题

为了完成飞机的预定功能,机上配置各种不同的系统,诸如操纵系统,液压系统、燃油系统、动力系统、空调系统、防冰防雨系统、氧化系统、电源系统、导航系统等等。其中液压系统是属于关键系统之一。该系统的工作情况直接与飞行安全密切相关。一般来说,它要承担飞机起落架的收放、刹车,各操纵活动面(副翼、方向     

锻造操作机液压系统设计与仿真

锻造操作机是核电、火电、轨道交通等重大装备制造的关键设备。针对锻造操作机高速、高精度以及可靠性的要求,对锻造操作机液压系统进行功能分析,在此基础上设计锻造操作机液压系统回路。锻造操作机液压控制系统包括夹持系统、提升俯仰系统、水平移动系统、缓冲系统、大车行走系统和夹钳旋转系统。采用平均流量法对液压泵站进行节能设计。在数学模型的基础上对液压系统的关键控制性能(快速性、准确性、起动性)和可靠性进行仿真分析研究。结果表明,通过对液压系统回路的合理设计,改善了液压系统的控制性能,提高了液压系统的可靠性,可为大流量液压系统的设计提供理论指导,实现锻造操作机的快速、精确、稳定、智能控制。     

某地下综合管廊的弱电与火灾报警系统设计

介绍了某地下综合管廊安防系统、火灾自动报警系统、通信与信息化系统的设计,其中,安防系统包括入侵报警系统、视频监控系统、电子巡更系统、出入口控制系统。     

高速公路机电工程运行管理和维护研究

高速公路机电系统被划分为六大系统,即监控系统、通信系统、收费系统、低压供配电系统、照明系统、隧道机电工程系统。在高速公路的建设和发展过程中,监控、收费、通信三大系统是同步进行,协调发展的。高速公路机电维护和管理中经常会出现一些问题,本文就对这些问题以及加强高速公路机电工程维护和管理的对策进行分析,以供参考。     

基于EMS的智能辅助系统研究及应用

基于EMS系统设计了智能辅助系统,该系统由辅助检查系统、自动化仿真系统、自动化验收系统三个模块组成,各个模块围绕EMS系统进行数据共享。系统首先通过仿真系统实现了对EMS系统的数据进行监听,然后通过验收系统对监听到的数据进行合理性检查而后验收,最后通过辅助检查系统对EMS系统的硬件状态、系统信息、电网模型等方面进行检查和分析,确保用户对EMS系统存在的风险进行及时管控。     

模拟仿真器在工业控制中的应用

随着仿真技术的发展,仿真技术应用目的趋于多样化、全面化。最初仿真技术是作为对实际系统进行试验的辅助工具而应用的,而后又用于训练目的,现在仿真系统的应用包括：系统概念研究、系统的可行性研究、系统的分析与设计、系统开发、系统测试与评估、系统操作人员的培训、系统预测、系统的使用与维护等各个方面。     

浅谈汽车各系统传热

在汽车发动机的两大机构五大系统,以及底盘的传动系统、行驶系统、制动系统、转向系统中,涉及传热学的系统较多,这些系统中的传热问题,会影响到各部件工况。本文着重讲述发动机、变速器、轴承、制动盘的传热情况。     

提高液压系统的效率

本文举例分析定量泵溢流阀系统、高低压泵卸荷阀系统、压力适应系统、压力补偿变量泵系统、功率适应系统及蓄能器系统的传动效率,借以说明提高液压系统效率的方法。     

大型电子洁净工厂弱电系统设计简述

结合液晶面板工厂、集成电路芯片工厂工程实例,简述大型电子洁净工厂弱电系统的设计方案及工程做法,包含电话/网络系统和安防系统(门禁、考勤、一卡通系统,闭路电视监控系统,巡更系统,入侵报警系统,周界报警系统,残疾人报警系统等)。     

直齿轮传动系统特征分析与静强度可靠性模型

齿轮传动系统是一个串联系统,但在系统与零件之间的关系、系统实现功能的方式、以及系统的时间属性等方面与传统意义上的串联系统有明显不同。从可靠性分析的角度,详细分析了齿轮传动系统在系统构型、载荷传递及失效等方面的特点。鉴于可靠性分析的需要,细化了机械系统分类,把串联系统划分为简单(空间或空域)串联系统(常构串联系统)和时域串联系统(变构串联系统)。根据在功能、结构、载荷等方面不同的系统,有针对性地研究可靠性分析与可靠性建模方法。以单级齿轮传动系统为例,建立了不同系统结构参数、不同服役条件下的系统可靠性模型,展示了系统可靠性变化规律,以及所建模型与传统串联系统模型之间的差异。     

PROFIBUS-DP从站在表格印刷机控制系统中的应用

针对印刷机外围设备分散、数据传输信息量大、实时性和可靠性要求高等问题,设计一种基于PROFIBUS-DP协议的I/O从站,用于表格印刷机的分布式控制系统.控制系统由监控计算机运行的软件PLC程序,通过PROFIBUS通信卡与现场I/O从站进行通信,形成分布式控制网络.介绍分布式控制系统的整体结构、工作原理及特点,分析PROFIBUS-DP协议,详细说明采用微控制器C8051F020和协议芯片SPC3开发I/O从站的硬件电路、软件设计流程,给出基于PRO-FIBUS现场总线的分布式控制系统网络组态与调试的方法.经系统测试和实际运行表明,I/O从站与监控计算机通信可靠、准确,实时性满足了印刷机控制系统的要求,具有一定的参考价值和广阔的应用前景.     

基于分布式智能控制技术的烟草制丝线集成系统研究

基于分布式智能控制技术的烟草制丝线集成系统是以分布式自动控制技术为基础,实现精细化的过程控制与生产执行。通过制丝线生产管理系统和柔性化的生产组织调度仿真系统,对制丝线生产的资源调配,企业核心竞争力都有着积极的推动作用。     

分布式系统环境下一种读写同步控制模型的实现

读写同步控制是分布式系统中的一个重要问题。给出了分布式系统环境下的一种读写同步控制模型,将多个读操作和写操作分布在不同主机上,基于ProActive提供的同步机制、XML部署描述器和SSH配置及图形监控工具IC2D仿真实现该模型。实验结果表明尽管多个读操作和写操作分布于多个计算节点上,他们也能协同读写共享数据,且能在不停顿正读或写的情况下为读操作或写操作指派不同的同步策略。     

Robust control of saturating systems with Markovian packet dropouts under distributed MPC

In this work, a robust control methodology is presented for saturating systems with packet dropouts under distributed model predictive control framework. The sequence of time instants when data dropout happens is modeled by a Markov chain. A packet dropout compensation strategy and an augmented Markov jump linear model are considered simultaneously. To design distributed model predictive controllers, the entire system is decomposed into coupled subsystems. Considering the influences of neighbor subsystems, a distributed predictive control synthesis involving packet dropouts and Markovian probabilities is developed by minimizing the worst-case performance index at each time instant. The input saturation constraints are also incorporated into the robust controller design under distributed model predictive control framework. Furthermore, both the recursive feasibility of the proposed robust control under distributed model predictive control and the closed-loop mean-square stability are proved. To show the effectiveness, the proposed methodology is validated by simulations on a continuous stirred tank reactor process and a DC control system.     

A Multi-Agent-Based Agile Shop Floor Control System

The ability of an enterprise to deliver new products quickly and efficiently to market is often the chief determinant of competitive success. The shop floor control system must be an open dynamic system with the capability of adapting and accepting radical unpredictable changes in its structures and industrial practices. This paper presents a new architecture for an agile shop floor control system. The architecture is based on the methodology of multi-agent systems in distributed artificial intelligence (DAI). The multi-agent system has some common characteristics such as: distribution, autonomy, interaction, and openness, which are helpful for transferring traditional architecture to a distributed, cooperative architecture for a shop floor control system. A bidding method based on the required production cost and processing time is also proposed. Using a distributed object-oriented technique, a CORBA-based multi-agent framework for an agile shop floor control system is constructed to integrate all the activity of the shop floor into a distributed intelligent open environment. To implement the framework, a coordination model between agents and behavioural models of some representative agents are established.     

基于CAN总线的900t轮胎式提梁机分布式控制系统

900t轮胎式提梁机是高速铁路建设的重要装备，由于其控制系统具有空间分布散、控制对象多、功能复杂等特点，故其控制系统是整体设计的关键．论述了在提梁机上设计3层网络构架体系的分布式控制系统以及分布式控制系统策略．通过数学建模，针对网络延时，说明了分布式控制系统对比例-积分-微分控制算法（PID）运用的影响．在TrueTime中对所设计的控制系统和策略进行了建模并仿真，得到所设计的控制系统稳定可靠的结果．     

DCOM and MMS–based control software architecture for automated manufacturing system

In this paper, we introduce the manufacturing message specification (MMS) and compare two distributed object approaches–distributed component object model (DCOM) and common object request broker architecture (CORBA), suggest characteristics that DCOM is more suitable for automated manufacturing system (AMS) control software integration. In order to make a control system provided with interoperability and reconfigurability etc., a hybrid control system is built for AMS, then a control software architecture is presented for AMS based on distributed object DCOM middleware and MMS standard. The object-oriented DCOM communication protocol is used to implement the MMS in a distributed object mode. DCOM and MMS combination brings the operating system independent communication capabilities to manufacturing devices such as CNC machine tools and industrial robots in AMS. Control software implementation of MMS concepts in the DCOM environment is particularly discussed. Finally, to verify the control software architecture for AMS, prototype development has been implemented in VC++ 6.0 developer environments.     

Design and implementation of an Internet based effective controlling and monitoring system with wireless fieldbus communications technologies for process automation--an experimental study

The network requirements of control systems in industrial applications increase day by day. The Internet based control system and various fieldbus systems have been designed in order to meet these requirements. This paper describes an Internet based control system with wireless fieldbus communication designed for distributed processes. The system was implemented as an experimental setup in a laboratory. In industrial facilities, the process control layer and the distance connection of the distributed control devices in the lowest levels of the industrial production environment are provided with fieldbus networks. In this paper, the Internet based control system that will be able to meet the system requirements with a new-generation communication structure, which is called wired/wireless hybrid system, has been designed on field level and carried out to cover all sectors of distributed automation, from process control, to distributed input/output (I/O). The system has been accomplished by hardware structure with a programmable logic controller (PLC), a communication processor (CP) module, two industrial wireless modules and a distributed I/O module, Motor Protection Package (MPP) and software structure with WinCC flexible program used for the screen of Scada (Supervisory Control And Data Acquisition), SIMATIC MANAGER package program ("STEP7") used for the hardware and network configuration and also for downloading control program to PLC.     

工业缝纫机电控产品质量在线检测与管理系统

介绍了一种利用计算机对生产线上的电控产品进行质量在线检测和管理的系统。分析了集散控制系统的组成,给出了系统实现方案、工作过程和原理。工业集散控制系统实现产品质量检测的集中管理和分散控制,是提高产品质量的保证。     

协同制造网络中基于知识的风险控制体系研究

为解决协同制造网络在复杂分布环境中的风险管理问题,需要建立一个稳定、集成的风险控制系统.分析了协同生产过程中的风险控制问题,指出基于知识的风险控制机制在协同制造网络中所起的重要作用.建立基于Agent的风险控制过程模型来适应动态分布的协同生产环境,并对模型中风险知识库的构成进行了说明.建立一种基于公共对象请求代理(CORBA)和工作流技术的风险控制体系框架,以一种过程框架的方法很好地解决了协同制造网络中风险的识别以及风险集中与分布控制问题.最后,介绍系统的实现与功能.