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Nonequilibrium work equalities in isolated quantum systems 被引量:1
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作者 柳飞 欧阳钟灿 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第7期53-60,共8页
We briefly introduce the quantum Jarzynski and Bochkov-Kuzovlev equalities .in isolated quantum Hamiltonian sys- tems, including their origin, their derivations using a quantum Feynman-Kac formula, the quantum Crooks ... We briefly introduce the quantum Jarzynski and Bochkov-Kuzovlev equalities .in isolated quantum Hamiltonian sys- tems, including their origin, their derivations using a quantum Feynman-Kac formula, the quantum Crooks equality, the evolution equations governing the characteristic functions of the probability density functions for the quantum work, and recent experimental verifications. Some resultsare given here for the first time. We particularly emphasize the formally structural consistence between these quantum equalities and their classical counterparts, which are useful for understanding the existing equalities and pursuing new fluctuation relations in other complex quantum systems. 展开更多
关键词 nonequilibrium isolated quantum systems work equality probability density function of quantumwork quantum Feynman-Kac formula
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Adaptive coupled synchronization of non-autonomous systems in ring networks 被引量:1
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作者 过榴晓 徐振源 胡满峰 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第3期836-841,共6页
The adaptive coupled synchronization method for non-autonomous systems is proposed. This method can avoid estimating the value of coupling coefficient. Under the uniform Lipschitz assumption, we derive the asymptotica... The adaptive coupled synchronization method for non-autonomous systems is proposed. This method can avoid estimating the value of coupling coefficient. Under the uniform Lipschitz assumption, we derive the asymptotical synchronization for a general coupling ring network with N identical non-autonomous systems~ even when N is large enough. Strict theoretical proofs are given. Numerical simulations illustrate the effectiveness of the present method. 展开更多
关键词 non-autonomous system adaptive synchronization chaotic synchronization ring net-works
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MY R&.D WORK IN THE FIELD OF HF RADAR SYSTEMS
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作者 Liu Yongtan(Harbin Polytechnic) 《Bulletin of the Chinese Academy of Sciences》 1995年第1期104-105,共2页
Since 1958. I bave been doing research and teaching work at Harbin Polytechnic on the theories of radar,navigational guidance,and signal processing & information treatment by developing new radar systems. In 1979,... Since 1958. I bave been doing research and teaching work at Harbin Polytechnic on the theories of radar,navigational guidance,and signal processing & information treatment by developing new radar systems. In 1979, I went to England in the status of an honorary research fellow and stayed there for two years.probing into HF radar systems under the guidance of the world-famous British marine telemetrist Professor Shearman at Birmingham University.Here.I briefly 展开更多
关键词 HF MY R D work IN THE FIELD OF HF RADAR systems
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Robot Position Control Using Force Information for Cooperative Work in Remote Robot Systems with Force Feedback
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作者 Satoru Ishikawa Yutaka Ishibashi +1 位作者 Pingguo Huang Yuichiro Tateiwa 《International Journal of Communications, Network and System Sciences》 2021年第1期1-13,共13页
This paper proposes robot position control using force information for cooperative work between two remote robot systems with force feedback in each of which a user operates a remote robot by using a haptic interface ... This paper proposes robot position control using force information for cooperative work between two remote robot systems with force feedback in each of which a user operates a remote robot by using a haptic interface device while observing work of the robot with a video camera. We also investigate the effect of the proposed control by experiment. As cooperative work, we deal with work in which two robots carry an object together. The robot position control using force information finely adjusts the position of the robot arm to reduce the force applied to the object. Thus, the purpose of the control is to avoid large force so that the object is not broken. In our experiment, we make a comparison among the following three cases in order to clarify how to carry out the control effectively. In the first case, the two robots are operated manually by a user with his/her both hands. In the second case, one robot is operated manually by a user, and the other robot is moved automatically under the proposed control. In the last case, the object is carried directly by a human instead of the robot which is operated by the user in the second case. As a result, experimental results demonstrate that the control can help each system operated manually by the user to carry the object smoothly. 展开更多
关键词 Remote Robot system Haptic Interface Device Force Feedback Cooperative work Robot Position Control EXPERIMENT
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THE VARIATIONAL PRINCIPLES OF COUPLED SYSTEMS IN PHOTOELASTICITY 被引量:1
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作者 付宝连 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1994年第1期37-48,共12页
This paper presents an energy principle, zero different principle of coupledsystems in photoelasticity, from which the potential energy, the complementary energy,generalized potential energy and generalized complemen... This paper presents an energy principle, zero different principle of coupledsystems in photoelasticity, from which the potential energy, the complementary energy,generalized potential energy and generalized complementary energy variationalprinciples of the coupled systems in photoelasticity are derived What is called the coupled systems means that two deformational bodies, forwhich figures, sizes,loads and boundary conditions are the same and they are all inactual states but they are made of different materials.Prototype body and model body in photoelasticity are essentially the coupledsystems, therefore the above principles become the theoretical basis of defining theinflunce of Poissons ratio v on accuracy of the frozen-stress method. 展开更多
关键词 PHOTOELASTICITY coupled systems zero different work principle coupled variational principle
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A method to refine the start-up scheme of compression and refrigeration systems in ethylene plants via dynamic simulation 被引量:2
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作者 Shengfu Zhang Yongchen Zhao +2 位作者 Tong Qiu Guang Song Jinsong Zhao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第8期1007-1012,共6页
Starting the cracking gas compressor and precooling the refrigeration system are keys to start-up of an ethylene plant and accounts for up to 50% of the total start-up time and plant flare emissions. Premature feeding... Starting the cracking gas compressor and precooling the refrigeration system are keys to start-up of an ethylene plant and accounts for up to 50% of the total start-up time and plant flare emissions. Premature feeding of cracking furnaces can be avoided if the cracking gas compressor is started and the refrigeration system is precooled in advance using mixed gas as the start-up working medium(SWM). Start-up scenario with mixed gas as SWM could significantly reduce the emission loss and shorten the precooling time. Research shows that making appropriate start-up scheme is important not only to ensure operational safety and feasibility, but also to reduce energy consumption. In this paper, a method is proposed to select suitable start-up operational parameters of compression and refrigeration system with sufficient safe operating ranges and short precooling time. The complex interrelation among key parameters of start-up is analyzed. It is found that higher energy consumption, especially for super high-pressure steam(SS), can promote operational safety and shorten the precooling time during start-up.Based on steady-state and dynamic simulation, appropriate operating parameter ranges are determined with reasonable SS consumption. A real case study demonstrates that an appropriate start-up scheme will optimize the operation. 展开更多
关键词 START-UP ETHYLENE PLANT START-UP working MEDIUM MIXED gas RUN Compression system
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Power Generation Systems Using Continuous Blowdown Waste Heat from Drum Boilers Driving an Organic Rankine Cycle 被引量:2
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作者 LIU Qiang DUAN Yuanyuan WAN Xucai 《中国电机工程学报》 EI CSCD 北大核心 2013年第35期I0001-I0014,共14页
提出了一种利用汽包锅炉排污系统余热的有机朗肯循环发电系统,有机工质回收扩容器疏水的热量,并通过气轮机发电。建立了系统的热力性能分析模型,并对R227ea、RC318、R236ea、R245fa、R245ca、R123和R113等7种工质的热力性能进行了优化... 提出了一种利用汽包锅炉排污系统余热的有机朗肯循环发电系统,有机工质回收扩容器疏水的热量,并通过气轮机发电。建立了系统的热力性能分析模型,并对R227ea、RC318、R236ea、R245fa、R245ca、R123和R113等7种工质的热力性能进行了优化。结果表明,临界温度高的工质,其o2循环的最佳主气温度(蒸发温度)反而低;亚临界循环采用干流体时,过热不利于余热的利用;超临界循环可以改善热源与工质间的温度匹配,有利于增大系统输出功,但是其运行压力高、大比热区的传热恶化等问题是实际运行和设计需要考虑的因素;R236ea的热力性能优于其余6种工质。 展开更多
关键词 朗肯循环 余热驱动 连续排污 发电系统 锅炉 燃煤电厂 标准煤耗率 发电量
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Security for Industrial Communication Systems
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《可编程控制器与工厂自动化(PLC FA)》 2006年第7期29-31,共3页
B. Network Architectures This section describes the main types of industrial and utility communication network topologies and protocols, in preparation for the discussion of specific security issues in the later secti... B. Network Architectures This section describes the main types of industrial and utility communication network topologies and protocols, in preparation for the discussion of specific security issues in the later sections. Communication networks for industrial automation are typically built in hierarchi- 展开更多
关键词 Security for Industrial Communication systems work PRO NODE
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IT Asset Management of Industrial Automation Systems
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《可编程控制器与工厂自动化(PLC FA)》 2005年第12期29-31,共3页
1. Introduction The installation and administration of large heterogeneous IT infrastructures, for enterprises as well industrial automation systems, are becoming more and more complex and time consuming. The growing ... 1. Introduction The installation and administration of large heterogeneous IT infrastructures, for enterprises as well industrial automation systems, are becoming more and more complex and time consuming. The growing number of interconnections between networks, the development of new intelligent IT devices, and increasingly sophisticated computer hard- 展开更多
关键词 In Man work ABB NDS SNMP WMI NODE IT Asset Management of Industrial Automation systems DMTF
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Middleware Architecture Interoperation of Synchronized Collaborative Design upon Heterogeneous CAD Systems 被引量:2
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作者 Wanfeng Dou Xiaodong Song Tao Peng 《通讯和计算机(中英文版)》 2010年第10期14-24,共11页
关键词 异构CAD系统 同步协同设计 中间件架构 互操作 Solidworks 国家气象中心 参数化特征 建模方法
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Constructing Index System for Evaluating Work Level in Rural Endowment Insurance
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作者 ZHAO Zhigang WANG Yalin 《Journal of Northeast Agricultural University(English Edition)》 CAS 2008年第3期90-96,共7页
This paper used fuzzy math principles, analyzed different aspects of the work of the current rural endowment insurance and formed the indices to assess the work level of the rural endowment insurance. After selecting ... This paper used fuzzy math principles, analyzed different aspects of the work of the current rural endowment insurance and formed the indices to assess the work level of the rural endowment insurance. After selecting the indices of the work level scientificly, constructed the index system to evaluate the work level of the rural endowment insurance and the index system was expressed in the form of math equation. In this way, an objective standard used to evaluate the work level of rural endowment insurance was establised. 展开更多
关键词 rural endowment insurance work level index system
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Assessment of Multiple Working Condition System Reliability with Agent-Based Simulation Method
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作者 曹军海 邢彪 申莹 《Journal of Donghua University(English Edition)》 EI CAS 2015年第6期974-978,共5页
The mission reliability assessment plays a great role in logistics planning and supporting resource optimization of complex system.But the current problem,which is difficult to solve,is how to model and analyze the ch... The mission reliability assessment plays a great role in logistics planning and supporting resource optimization of complex system.But the current problem,which is difficult to solve,is how to model and analyze the characters of system reliability under the complex mission profile.In order to solve the problem,an agentbased simulation method was used to assess reliability for complex systems with various random working conditions.A multi-working condition simulation agent(MA)was designed and used to simulate the random transferring process of working conditions of system,and it cooperated with system simulation agents(SAs)and unit simulation agents(UAs)to realize system mission reliability(MR)simulation.Through simulation experiments,effect of multiple working conditions mission on the reliability of system was analyzed by comparing with the basic reliability condition.Feasibility and efficiency of the method were proved through simulation experiments of the case system.The research result provides a viable and useful method and a solution for MR analysis and assessment of complex systems in multi-working conditions,which can help to evaluate the reliability of operating system orienting to the practical mission and environment,and it is meaningful for the reliability analysis and the design of complex systems. 展开更多
关键词 system reliability multi-working condition system agentbased simulation mission profile reliability assessment
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An Improved Worktable and Guide System for a Handshearing Machine
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作者 Mogaji Pius Bamidele 《材料科学与工程(中英文B版)》 2012年第1期64-69,共6页
关键词 工作台 系统 指南 生产成本 金属切削 生产过程 优化使用 镀锌钢板
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Disease, Death and <i>Dhandha: Gharwali’s</i>Perspectives on the Impact of AIDS on <i>Devadasi</i>System and the Sex Work in South India
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作者 Kaveri Gurav James Blanchard 《World Journal of AIDS》 2013年第1期26-32,共7页
Traditional Devadasi system based sex work (dhandha) is practiced inIndia. The communities that practice this system are affected severely by AIDS epidemic. Through this paper we present the views of gharwalis (brothe... Traditional Devadasi system based sex work (dhandha) is practiced inIndia. The communities that practice this system are affected severely by AIDS epidemic. Through this paper we present the views of gharwalis (brothel madams) regarding the impact of AIDS on the traditional system (Devadasi system) of initiating girls as sex workers (Devadasis) and on the practice of sex work (dhandha) associated with that system. Qualitative in-depth interviews were conducted with twelve gharwalis as a follow-up of a cohort study, which investigated the patterns and determinants of sex worker migration from northern Karnataka to southern Maharashtra, in India. According to gharwalis, the disease (AIDS) consequences;death, fear and stigma affected dhandha operations, changed the attitude of the Devadasi community against the practice of dhandha and the Devadasi system, besides, influenced the community to take actions to stop the practice of dhandha and the Devadasi system. The findings suggest that the interplay between the disease consequences and the community’s response to those consequences contribute to transition dhandha and the Devadasi system. We discuss our findings, describe the transition and the consequent risk enhancing conditions. Finally, highlight the need to address these conditions to reduce Devadasis risk and vulnerability to HIV infection. 展开更多
关键词 India Devadasi system Gharwali SEX work HIV/AIDS
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Effects of Spherical Light-weight Aggregates Additions on Workability and Mechanical Properties of Al_2O_3-SiO_2 System Castables
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作者 YU Renhong LIU Pengcheng +1 位作者 DONG Gaofeng DONG Hongqin 《China's Refractories》 CAS 2017年第4期1-6,共6页
In order to clarify the effect of spherical light-weight aggregates addition on properties of A12 07 - Si02 system castables, adopting ATO mullite traditional light-weight aggregates and ATO mullite spherical light-we... In order to clarify the effect of spherical light-weight aggregates addition on properties of A12 07 - Si02 system castables, adopting ATO mullite traditional light-weight aggregates and ATO mullite spherical light-weight aggre- gates, bauxite homogenization powder, microsilica , cal- cium aluminate cement as main raw materials, light- weight Al2 03 - SiO2 system castables were prepared by replacing conventional light-weight aggregate with spherical light-weight aggregates. The effects of spheri- cal light-weight aggregates addition on workability, me- chanical properties of castables after heated at different temperatures were researched; the microstructure of the aggregates was analyzed by SEM. The result shows that the introduction of spherical light-weight aggregates can significantly improve the flowability and reduce the water addition of the castables. Water demand of the castable is reduced from 18% with the conventional light-weight aggregates to 14% with spherical light-weight aggre- gates. In addition, light-weight castables prepared by spherical aggregates can keep the same workability with- in a wider range of water addition. Therefore, spherical aggregates are user-friendly. The introduction of spheri- cal light-weight aggregates is favorable to packing densi- ty and mechanical properties of castables, such as cold crushing strength, cold modulus of rupture, hot modulus of rupture at 1 200℃. 展开更多
关键词 spherical light-weight aggregates ability mechanical properties alumina - silica castables work- system
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Dynamic Simulation of Solid Adsorption Solar Refrigerator System with AC/CH<sub>3</sub>OH as a Working Pair
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作者 Anan Pongtornkulpanich 《Energy and Power Engineering》 2014年第12期459-465,共7页
Solid adsorption system, one of alternative refrigeration systems, is utilized to provide cold for refrigerator or air-conditioner and can be operated by assistance of solar heat. System performance study through comp... Solid adsorption system, one of alternative refrigeration systems, is utilized to provide cold for refrigerator or air-conditioner and can be operated by assistance of solar heat. System performance study through computer usage to develop simulation program and simulate behaviors of system operation can give designed system which suits for user’s need. Also, the present study aims to develop dynamic simulation program of solid adsorption refrigeration system operated by solar assistance to simulate behaviors of system operation and its performance. Flat plate collectror is utilized to provide thermal energy for system’s adsorber and activated carbon/methanol is used to be a suitable working pair. Simulation procedure starts with various solar radiation intensities as input energy on solar collector and water is used as collector working fluid. Behavior of system operation can be considered to be 4 steps as isosteric heating, isobaric desorption, isosteric cooling and isobaric adsorption, respectively. This research studies the effect of varying solar radiation intensity on temperature, pressure of adsorber, adsorption ratio at each steps of system operated ranging from 6:00 am (the first day) to 6:00 am (the next day) and system performance which is defined as coefficient of performance, COP. In addition, the simulation result shows monthly average COP of 0.43 compared to a result of another previous research work under the same operating condition and the percentage error is 7.5%. 展开更多
关键词 Lumped Parameter Dynamic Simulation Program SOLID ADSORPTION Refrigeration system SOLAR Energy working Pair
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Social Work Involved in Targted Poverty Alleviation: From Individual Aid to System Change
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作者 Jin Yutong Wu Lingwei 《Contemporary Social Sciences》 2018年第4期57-69,共13页
The development of social work is to some extent a history of the struggle against poverty. Social work enabled targeted poverty alleviation aims to form a two–way force to implement targeted poverty alleviation poli... The development of social work is to some extent a history of the struggle against poverty. Social work enabled targeted poverty alleviation aims to form a two–way force to implement targeted poverty alleviation policies in a bid to create a new situation featuring top–down policy guidance and bottom–up social engagement. Social work enabled targeted poverty alleviation addresses the bureaucratic defects of government dominance, upgrades the narrow conception of targeted poverty alleviation as individual aid, and pays more attention to the interactions between the poor and environmental elements and the interactions within and between systems from the perspective of eco–system. In practice, this type of poverty alleviation is manifested as social work driven integral specialized poverty alleviation. By organically combining the four systems of subjects, service objects, work processes and implementation results, it advances current targeted poverty alleviation from the mid–shallow level to the deep level. It is expected to fulfill the intrinsic policy objectives of targeted poverty alleviation and explore a supporting system for realizing the modernization of national governance system and capacity in rural areas. 展开更多
关键词 targeted poverty alleviation social work eco–system AID social participation
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A Review on Technologies for the Use of CO2 as a Working Fluid in Refrigeration and Power Cycles
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作者 Orelien T. Boupda Hyacinthe D. Tessemo +3 位作者 Isidore B. Nkounda Fongang Francklin G. Nyami Frederic Lontsi Thomas Djiako 《Energy and Power Engineering》 2024年第6期217-256,共40页
The use of carbon dioxide as a working fluid has been the subject of extensive studies in recent years, particularly in the field of refrigeration where it is at the heart of research to replace CFC and HCFC. Its ther... The use of carbon dioxide as a working fluid has been the subject of extensive studies in recent years, particularly in the field of refrigeration where it is at the heart of research to replace CFC and HCFC. Its thermodynamic properties make it a fluid of choice in the efficient use of energy at low and medium temperatures in engine cycles. However, the performance of transcritical CO2 cycles weakens under high temperature and pressure conditions, especially in refrigeration systems;On the other hand, this disadvantage becomes rather interesting in engine cycles where CO2 can be used as an alternative to the organic working fluid in small and medium-sized electrical systems for low quality or waste heat sources. In order to improve the performance of systems operating with CO2 in the field of refrigeration and electricity production, research has made it possible to develop several concepts, of which this article deals with a review of the state of the art, followed by analyzes in-depth and critical of the various developments to the most recent modifications in these fields. Detailed discussions on the performance and technical characteristics of the different evolutions are also highlighted as well as the factors affecting the overall performance of the systems studied. Finally, perspectives on the future development of the use of CO2 in these different cycles are presented. 展开更多
关键词 Refrigeration Cycle Power Cycle system Performance Transcritical CO2 Cycles working Fluid
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基于SolidWorks二次开发的三维实时运动仿真方法 被引量:6
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作者 黄晓辰 张明路 +2 位作者 李满宏 孙凌宇 张小俊 《机械设计》 CSCD 北大核心 2014年第12期12-15,共4页
针对机器人三维实时运动仿真常用方法中不能与控制系统开发平台相融合、缺乏算法支持的问题,以用于检测压力容器的检测机器人为研究对象,设计出针对该机器人的三维实时控制系统软件。此软件将控制系统与三维实时仿真平台相融合,不仅能... 针对机器人三维实时运动仿真常用方法中不能与控制系统开发平台相融合、缺乏算法支持的问题,以用于检测压力容器的检测机器人为研究对象,设计出针对该机器人的三维实时控制系统软件。此软件将控制系统与三维实时仿真平台相融合,不仅能够远程对检测机器人生成并下达控制指令,而且利用Visual C#软件对Solid Works软件二次开发后形成的三维实时仿真平台,对机器人的运动状态进行实时仿真。现场使用结果表明,使用此软件能够安全可靠地对压力容器进行检测,三维实时仿真平台能有效提高仿真的精确度,实现对检测机器人运动状态进行全方位观测。 展开更多
关键词 机器人 控制系统 SOLIDworkS二次开发 三维实时仿真
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LonWorks在电除尘器实验系统中的应用 被引量:2
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作者 王洋 王宁会 《仪器仪表学报》 EI CAS CSCD 北大核心 2001年第z2期280-281,共2页
本文论述了 L onworks现场总线在火电厂电除尘器实验系统中的应用。该系统以研究电除尘器稳态工作的条件为目的 ,要求完成对现场所有设备的监控、以及对现场所有数据的处理等功能。由于 L on Works的应用 ,满足了该实验系统的稳定性、... 本文论述了 L onworks现场总线在火电厂电除尘器实验系统中的应用。该系统以研究电除尘器稳态工作的条件为目的 ,要求完成对现场所有设备的监控、以及对现场所有数据的处理等功能。由于 L on Works的应用 ,满足了该实验系统的稳定性、开放性的要求 。 展开更多
关键词 现场总线控制系统 LONworkS
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