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Programmable Logic Controller Block Monitoring System for Memory Attack Defense in Industrial Control Systems
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作者 Mingyu Lee Jiho Shin Jung Taek Seo 《Computers, Materials & Continua》 SCIE EI 2023年第11期2427-2442,共16页
Cyberattacks targeting industrial control systems(ICS)are becoming more sophisticated and advanced than in the past.A programmable logic controller(PLC),a core component of ICS,controls and monitors sensors and actuat... Cyberattacks targeting industrial control systems(ICS)are becoming more sophisticated and advanced than in the past.A programmable logic controller(PLC),a core component of ICS,controls and monitors sensors and actuators in the field.However,PLC has memory attack threats such as program injection and manipulation,which has long been a major target for attackers,and it is important to detect these attacks for ICS security.To detect PLC memory attacks,a security system is required to acquire and monitor PLC memory directly.In addition,the performance impact of the security system on the PLC makes it difficult to apply to the ICS.To address these challenges,this paper proposes a system to detect PLC memory attacks by continuously acquiring and monitoring PLC memory.The proposed system detects PLC memory attacks by acquiring the program blocks and block information directly from the same layer as the PLC and then comparing them in bytes with previous data.Experiments with Siemens S7-300 and S7-400 PLC were conducted to evaluate the PLC memory detection performance and performance impact on PLC.The experimental results demonstrate that the proposed system detects all malicious organization block(OB)injection and data block(DB)manipulation,and the increment of PLC cycle time,the impact on PLC performance,was less than 1 ms.The proposed system detects PLC memory attacks with a simpler detection method than earlier studies.Furthermore,the proposed system can be applied to ICS with a small performance impact on PLC. 展开更多
关键词 programmable logic controller industrial control system attack detection
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The Impact of Optimizing Details in the Operating Room on the Level of Knowledge, Attitude, and Practice of Hospital Infection Prevention and Control by Surgeons, as Well as the Effectiveness of Infection Control
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作者 Yuanyuan Zhang 《Surgical Science》 2024年第7期421-429,共9页
Objective: This paper aims to explore the impact of optimizing details in the operating room on the level of knowledge, attitude, and practice of hospital infection prevention and control by surgeons, as well as the e... Objective: This paper aims to explore the impact of optimizing details in the operating room on the level of knowledge, attitude, and practice of hospital infection prevention and control by surgeons, as well as the effectiveness of infection control. Methods: From January 2022 to June 2023, a total of 120 patients were screened and randomly divided into a control group (routine care and hospital infection management) and a study group (optimizing details in the operating room). Results: Significant differences were found between the two groups in the data of surgeons’ level of knowledge, attitude, and practice in hospital infection prevention and control, infection rates, and nursing satisfaction, with the study group showing better results (P Conclusion: The use of optimizing details in the operating room among surgeons can effectively improve surgeons’ level of knowledge, attitude, and practice in hospital infection prevention and control, reduce infection occurrence, and is worth promoting. 展开更多
关键词 Optimizing Details in the operating Room Infection Level of Knowledge ATTITUDE and Practice Infection Control
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Operating Parameters of the District Heating Substation Cooperating With the Installation of Technological Air Conditioning With High Efficiency of Heat Recovery
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作者 Żarski Kazimierz Kryża Mariusz 《Chinese Business Review》 2024年第1期1-12,共12页
The article analyses the problem of determining the operating parameters of the district heating substation cooperating with the air heating system in technological air conditioning systems equipped with heat exchange... The article analyses the problem of determining the operating parameters of the district heating substation cooperating with the air heating system in technological air conditioning systems equipped with heat exchangers with high efficiency of heat recovery.Attention was paid to the correct selection of heat exchangers for the heat output balance depending on the heat recovery protection algorithms against a drop in the temperature of the heat transfer surface below 0℃.Critical parameters were determined in Polish climatic conditions,at which the operation of the heat recovery exchanger in the air conditioning system is switched off or limited.It has been proven that the proper functioning of the district heating substation cooperating with the installation of air conditioning with high heat recovery efficiency requires the use of two heat exchangers with different characteristics,equipped with properly selected temperature control systems.The optimal model of cooperation between the technological air conditioning system and the heating substation was also indicated. 展开更多
关键词 ventilation of operating theatre air conditioning flow control in heating circuit
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Teaching Reform and Exploration of Practical Courses Based on Programmable Control
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作者 Hang Xu 《Journal of Contemporary Educational Research》 2024年第6期211-215,共5页
As the country continues to promote the development of intelligent manufacturing,all industries are carrying out enterprise automation upgrading,the Pearl River Delta Intelligent Manufacturing Conference held in March... As the country continues to promote the development of intelligent manufacturing,all industries are carrying out enterprise automation upgrading,the Pearl River Delta Intelligent Manufacturing Conference held in March 2024 provides a direction guide for each enterprise on how to integrate the intelligent manufacturing technology into each link and provide direction guidance for enterprises to create new models and new business formats.College teachers,in focusing on the teaching process,should closely match the enterprise and social needs and cultivate excellent students.As the core controller of automation control,the application of programmable controllers in teaching is particularly important.In practical classes,by setting progressive difficulty,project guidance,team collaboration,and other links,students can master the automation equipment design of programmable control in repeated practice. 展开更多
关键词 programmable controller Practical course Project guidelines TEAMWORK
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Dawning-1000 PROOS Distributed Operating System
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作者 孙凝晖 刘文卓 +3 位作者 刘宏 王川宝 陆雪琳 张浩 《Journal of Computer Science & Technology》 SCIE EI CSCD 1997年第2期160-166,共7页
PROOS is a distributed operating system running on the computing nodes of massively parallel processing computer Dawning-1000. It is an efficient and easily extendible micro kernel operating system. It supports the in... PROOS is a distributed operating system running on the computing nodes of massively parallel processing computer Dawning-1000. It is an efficient and easily extendible micro kernel operating system. It supports the intel NX message passing interface for communication. 展开更多
关键词 Dawning-1000 distributed operating system message passing flow control
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Design of 32 kbit one-time programmable memory for microcontroller units 被引量:1
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作者 JEON Hwang-gon CHOI In-hwa +1 位作者 HA Pan-bong KIM Young-hee 《Journal of Central South University》 SCIE EI CAS 2012年第12期3475-3483,共9页
A 32 kbit OTP(one-time programmable)memory for MCUs(micro-controller units)used in remote controllers was designed.This OTP memory is used for program and data storage.It is required to apply 5.5V to BL(bit-line)and 1... A 32 kbit OTP(one-time programmable)memory for MCUs(micro-controller units)used in remote controllers was designed.This OTP memory is used for program and data storage.It is required to apply 5.5V to BL(bit-line)and 11V to WL(word-line)for a OTP cell of 0.35μm ETOX(EEPROM tunnel oxide)type by MagnaChip.We use 5V transistors on column data paths to reduce the area of column data paths since they require small areas.In addition,we secure device reliability by using HV(high-voltage)transistors in the WL driver.Furthermore,we change from a static logic to a dynamic logic used for the WL driver in the core circuit.Also,we optimize the WD(write data)switch circuit.Thus,we can implement them with a small-area design.In addition,we implement the address predecoder with a small-area logic circuit.The area of the designed 32 kbit OTP with 5V and HV devices is 674.725μm×258.75μm(=0.1745mm2)and is 56.3% smaller than that using 3.3V devices. 展开更多
关键词 one-time programmable memory micro controller unit EEPROM tunnel oxide small-area
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A novel fuzzy logic direct torque controller for a permanent magnet synchronous motor with a field programmable gate array 被引量:1
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作者 陈永军 《Journal of Chongqing University》 CAS 2008年第3期228-233,共6页
A high-performance digital servo system built on the platform of a field programmable gate array (FPGA),a fully digitized hardware design scheme of a direct torque control (DTC) and a low speed permanent magnet synchr... A high-performance digital servo system built on the platform of a field programmable gate array (FPGA),a fully digitized hardware design scheme of a direct torque control (DTC) and a low speed permanent magnet synchronous motor (PMSM) is proposed. The DTC strategy of PMSM is described with Verilog hardware description language and is employed on-chip FPGA in accordance with the electronic design automation design methodology. Due to large torque ripples in low speed PMSM,the hysteresis controller in a conventional PMSM DTC was replaced by a fuzzy controller. This FPGA scheme integrates the direct torque controller strategy,the time speed measurement algorithm,the fuzzy regulating technique and the space vector pulse width modulation principle. Experimental results indicate the fuzzy controller can provide a controllable speed at 20 r min-1 and torque at 330 N m with satisfactory dynamic and static performance. Furthermore,the results show that this new control strategy decreases the torque ripple drastically and enhances control performance. 展开更多
关键词 fuzzy control direct torque control field programmable gate array permanent magnet synchronous motor
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Application of Programmable Controller in a Rail Welding Machine
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作者 Dai Hong Department of Materials Engineering, Southwest Jiaotong University, Chengdu 610031, China Xiang Junjie Long Zhuohong Chengdu Rail Welding Factory, Chengdu 610037, China 《Journal of Modern Transportation》 1997年第1期80-85,共6页
An innovation is conducted on a K190πK rail auto welding machine because of its poor stability in quality of welding joints. A new control system based on a programmable controller is designed to replace the old o... An innovation is conducted on a K190πK rail auto welding machine because of its poor stability in quality of welding joints. A new control system based on a programmable controller is designed to replace the old one. The new control system is of higher accuracy in controlling sequence and good ability in anti disturbance, and is convenient to operate. The comparison tests are carried out. The experimental results show that the quality of welded joints is greatly increased by the improved welding mechine. 展开更多
关键词 rail welding maching programmable controller control system quality of welding joint
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Embedded Programmable Single Point Multiple Output Intelligent Data Acquisition and Transmission System
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作者 Guoli QU Yun WU +1 位作者 Gaihua XU Lin CHEN 《Asian Agricultural Research》 2016年第11期54-60,共7页
To effectively solve the problems of inconsistent communication protocols in automatic monitoring equipment,and limited data acquisition transmission and monitoring equipment,this paper developed programmable single p... To effectively solve the problems of inconsistent communication protocols in automatic monitoring equipment,and limited data acquisition transmission and monitoring equipment,this paper developed programmable single point multiple output intelligent data acquisition and transmission system. It made an in-depth elaboration of the data acquisition and transmission system from hardware design,software architecture and principle,main functions and technical parameters. Finally,it came up with four innovation points:(i) intelligent(automatic)matching a variety of communication protocols for environmental monitoring equipment,(ii) realizing multi-protocol and multi-target parallel data transmission,(iii) realizing remote dynamic input of control instructions through wired or wireless network,and(iv) supporting configuration(process) simulation of field equipment DCS operating conditions. 展开更多
关键词 programmable Single point multiple output Intelligent matching multi-protocols Reverse remote control
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Application of PLC programmable control technology in the mine pit transportation system
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《International English Education Research》 2013年第12期44-46,共3页
This paper summarizes the definition, function, and characteristics of the programmable conlrol technology, and especially analyzes the operation mode of the 750V DC traction power supply system, the protection settin... This paper summarizes the definition, function, and characteristics of the programmable conlrol technology, and especially analyzes the operation mode of the 750V DC traction power supply system, the protection setting the defects of the original system and the factors influencing the safety of power supply. Aimed at the equipment of the PLC programmable control system used in the mine transportation system in recent years, combining parts of the PLC programmable control system equipment used and installed in Tong Ting Coal Mine, this paper introduces the role of the PLC programmable control system and the economic benefits and safety effect. 展开更多
关键词 PLC programmable controller mine transportation
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Application of Programmable Logic Controller in Hydraulic Spring Eye Machine
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作者 Yan Zhao Linzhi Cheng 《通讯和计算机(中英文版)》 2006年第1期97-101,共5页
关键词 编程人员 编程逻辑 管理程序 操作系统
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Programmable Control System with Applications in Alternating Current Motors Control
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作者 Andrei Cozma Dan Pitica 《通讯和计算机(中英文版)》 2011年第9期771-779,共9页
关键词 可编程控制系统 交流电动机 电动机控制 高速数字信号处理器 电流控制器 三相异步电动机 应用 信号采集模块
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Real Time Control System for Metro Railways Using PLC & SCADA
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作者 Ishu Tomar Indu Sreedevi Neeta Pandey 《Intelligent Automation & Soft Computing》 SCIE 2023年第2期1403-1421,共19页
This paper proposes to adopt SCADA and PLC technology for the improvement of the performance of real time signaling&train control systems in metro railways.The main concern of this paper is to minimize the failure... This paper proposes to adopt SCADA and PLC technology for the improvement of the performance of real time signaling&train control systems in metro railways.The main concern of this paper is to minimize the failure in automated metro railways system operator and integrate the information coming from Operational Control Centre(OCC),traction SCADA system,traction power control,and power supply system.This work presents a simulated prototype of an automated metro train system operator that uses PLC and SCADA for the real time monitoring and control of the metro railway systems.Here,SCADA is used for the visualization of an automated process operation and then the whole opera-tion is regulated with the help of PLC.The PLC used in this process is OMRON(NX1P2-9024DT1)and OMRON’s Sysmac studio programming software is used for developing the ladder logic of PLC.The metro railways system has deployed infrastructure based on SCADA from the power supply system,and each station’s traction power control is connected to the OCC remotely which commands all of the stations and has the highest command priority.An alarm is triggered in the event of an emergency or system congestion.This proposed system overcomes the drawbacks of the current centralized automatic train control(CATC)system.This system provides prominent benefits like augmenting services which may enhance a network’s full load capacity and networkflexibility,which help in easy modification in the existing program at any time. 展开更多
关键词 Train control system AUTOMATION PLC(programmable logic controller) SCADA(supervisory control and data acquisition)
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Optimization of Control Loops and Operating Parameters for Three-Phase Separators Used in Oilfield Central Processing Facilities
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作者 Zhenfeng Li Yaqiao Li Guangjun Wei 《Fluid Dynamics & Materials Processing》 EI 2023年第3期635-649,共15页
In this study,the Stokes formula is used to analyze the separation effect of three-phase separators used in a Oilfield Central Processing Facility.The considered main influencing factors include(but are not limited to... In this study,the Stokes formula is used to analyze the separation effect of three-phase separators used in a Oilfield Central Processing Facility.The considered main influencing factors include(but are not limited to)the typical size of oil and water droplets,the residence time and temperature of fluid and the dosage of demulsifier.Using the“Specification for Oil and Gas Separators”as a basis,the control loops and operating parameters of each separator are optimized Considering the Halfaya Oilfield as a testbed,it is shown that the proposed approach can lead to good results in the production stage. 展开更多
关键词 Distributed control system(DCS) three-phase separator control loop operating parameter
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A Novel Design Framework for Smart Operating Robot in Power System 被引量:1
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作者 Qiang Wang Xiaojing Yang +4 位作者 Zhigang Huang Shiqian Ma Qiao Li David Wenzhong Gao Fei-Yue Wang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2018年第2期531-538,共8页
This paper proposes the concept and framework of smart operating system based on the artificial intelligence(AI)techniques. The demands and the potential applications of AI technologies in power system control centers... This paper proposes the concept and framework of smart operating system based on the artificial intelligence(AI)techniques. The demands and the potential applications of AI technologies in power system control centers is discussed in the beginning of the paper. The discussion is based on the results of a field study in the Tianjin Power System Control Center in China. According to the study, one problem in power systems is that the power system analysis system in the control center is not fast and powerful enough to help the operators in time to deal with the incidents in the power system. Another issue in current power system control center is that the operation tickets are compiled manually by the operators, so that it is less efficient and human errors cannot be avoided. Based on these problems, a framework of the smart operating robot is proposed in this paper, which includes an intelligent power system analysis system and a smart operation ticket compiling system to solve the two problems in power system control centers. The proposed framework is mainly based on the AI techniques, especially the neural network with deep learning, since it is faster and more capable of dealing with the highly nonlinear and complex power system. 展开更多
关键词 Index Terms-Artificial intelligence deep learning human-in-the-loop power system control center power system operatingrobot machine learning.
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Research on Active Safety Methodologies for Intelligent Railway Systems
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作者 Yong Qin Zhiwei Cao +6 位作者 Yongfu Sun Linlin Kou Xuejun Zhao Yunpeng Wu Qinghong Liu Mingming Wang Limin Jia 《Engineering》 SCIE EI CAS CSCD 2023年第8期266-279,共14页
Safety is essential when building a strong transportation system.As a key development direction in the global railway system,the intelligent railway has safety at its core,making safety a top priority while pursuing t... Safety is essential when building a strong transportation system.As a key development direction in the global railway system,the intelligent railway has safety at its core,making safety a top priority while pursuing the goals of efficiency,convenience,economy,and environmental friendliness.This paper describes the state of the art and proposes a system architecture for intelligent railway systems.It also focuses on the development of railway safety technology at home and abroad,and proposes the active safety method and technology system based on advanced theoretical methods such as the in-depth integration of cyber–physical systems(CPS),data-driven models,and intelligent computing.Finally,several typical applications are demonstrated to verify the advancement and feasibility of active safety technology in intelligent railway systems. 展开更多
关键词 Intelligent railway system Active safety methodology Prognostics and health management Intelligent surrounding perception Operation and maintenance risk control
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基于5G多接入边缘计算的云化PLC系统架构设计与应用 被引量:3
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作者 冯毅雄 杨晨 +5 位作者 胡炳涛 赖颢善 石莹 宋光敏 汪勇 谭建荣 《计算机辅助设计与图形学学报》 EI CSCD 北大核心 2024年第1期33-46,共14页
随着工业控制系统对柔性化、扁平化的要求不断提升,以PLC为构建基础的传统工业控制网络在大规模接入、算力提升和部署灵活性方面均受到限制.针对这些问题,融合5G网络和边缘计算技术,设计了基于5G多接入边缘计算的云化PLC系统架构,阐述... 随着工业控制系统对柔性化、扁平化的要求不断提升,以PLC为构建基础的传统工业控制网络在大规模接入、算力提升和部署灵活性方面均受到限制.针对这些问题,融合5G网络和边缘计算技术,设计了基于5G多接入边缘计算的云化PLC系统架构,阐述了该架构的运行机制和所涉及的关键技术;在此基础上,进行PLC系统的云化部署和调试,实现了工业现场、企业数据中心、5G网络和边缘网络的集成;最后,通过在某汽车制造公司产线改造过程中的应用,验证了所提架构的有效性. 展开更多
关键词 5G 边缘计算 云化PLC(可编程逻辑控制器) 架构设计
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Research on the cooperative train control method in the metro system for energy saving
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作者 Siyao Li Bo Yuan +1 位作者 Yun Bai Jianfeng Liu 《Railway Sciences》 2023年第3期371-394,共24页
Purpose–To address the problem that the current train operation mode that train selects one of several offline pre-generated control schemes before the departure and operates following the scheme after the departure,... Purpose–To address the problem that the current train operation mode that train selects one of several offline pre-generated control schemes before the departure and operates following the scheme after the departure,energy-saving performance of the whole metro system cannot be guaranteed.Design/methodology/approach–A cooperative train control framework is formulated to regulate a novel train operation mode.The classic train four-phase control strategy is improved for generating specific energy-efficient control schemes for each train.An improved brute force(BF)algorithm with a two-layer searching idea is designed to solve the optimisation model of energy-efficient train control schemes.Findings–Case studies on the actual metro line in Guangzhou,China verify the effectiveness of the proposed train control methods compared with four-phase control strategy under different kinds of train operation scenarios and calculation parameters.The verification on the computation efficiency as well as accuracy of the proposed algorithm indicates that it meets the requirement of online optimisation.Originality/value–Most existing studies optimised energy-efficient train timetable or train control strategies through an offline process,which has a defect in coping with the disturbance or delays effectively and promptly during real-time train operation.This paper studies an online optimisation of cooperative train control based on the rolling optimisation idea,where energy-efficient train operation can be realised once train running time is determined,thus mitigating the impact of unpredictable operation situations on the energy-saving performance of trains. 展开更多
关键词 Train operation scheme Energy saving Cooperative control Metro system
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Management System Activities of the Operation and Utilization of GHARR-1
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作者 Edward Shitsi Henry Cecil Odoi +10 位作者 Kwame Gyamfi Philip Dordoh-Gasu Isaac Kwasi Baidoo Edward Oscar Amponsah-Abu Emmanuel Kwesi Boafo Samuel Yao Ganyaglo Samuel Boakye Dampare Henry Kwame Obeng William Osei-Mensah Wilfred Sedofia Massiasta Robert Ekow Quagraine 《World Journal of Engineering and Technology》 2023年第4期807-826,共20页
The Ghana Research Reactor-1 (GHARR-1) is a 34 kW low enriched uranium (LEU) Miniature Neutron Source Reactor (MNSR), tank-in-pool type and cooled by natural circulation under atmospheric pressure operating conditions... The Ghana Research Reactor-1 (GHARR-1) is a 34 kW low enriched uranium (LEU) Miniature Neutron Source Reactor (MNSR), tank-in-pool type and cooled by natural circulation under atmospheric pressure operating conditions. GHARR-1 is owned by Ghana Atomic Energy Commission (GAEC) and operated by National Nuclear Research Institute (NNRI), one of the institutes of GAEC. GHARR-1 is housed by Nuclear Reactors Research Centre (NRRC), one of the Centres of NNRI. Management/Administration, Radiation protection, Reactor operation and maintenance, Reactor utilization and Physical protection are the various systems/units that integrate to manage the activities of operation and utilization of GHARR-1 in addition to the quality assurance and quality control management system of the research reactor facility. The GHARR-1 which is currently in operation follows a robust maintenance culture adopted by the management system and this has made it possible to keep the reactor in operation with minimal interruption. The management system activities adopted at the Centre to ensure safety of the workers, public and the research reactor facility include authorization of the operation of the reactor for any experiments/modifications;providing material and financial resources for maintaining the research reactor facility;following standard procedures while carrying out Neutron Activation Analysis;participation in IAEA proficiency test;irradiation sites/positions characterization;following standard procedures while carrying out reactor operation and maintenance including reactor and pool water purification and other related activities;monitoring radiation levels in the controlled, supervised and uncontrolled areas of the research reactor facility as well as during reactor operation and maintenance;controlling the physical entry of the workers and public into the research reactor facility;and ensuring that the security structures provided to protect the reactor facility are functioning properly. The thorough knowledge on the functions of the various components that make up the electrical/electronic and control systems of the reactor has been observed to be important for continuous successful maintenance of the research reactor to keep the reactor in operation. This work provides some management system activities adopted to monitor the activities of the research reactor operation and utilization to guarantee safety of workers, public and the environment as well as to safeguard a continuous operation of the research reactor. These management system activities adopted among others, are in the form of Monitoring Forms provided for monitoring the activities of the research reactor operation and utilization in order to ensure standard procedures and specifications are followed and quality services are rendered to the public. 展开更多
关键词 Management systems Quality Assurance and Quality Control Research Re-actor Operation and Utilization Monitoring Forms Ghana Research Reactor-1 (GHARR-1)
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基于PLC技术的联合收割机电气控制系统设计 被引量:2
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作者 梁吟曦 《农机化研究》 北大核心 2024年第2期221-224,共4页
以联合收割机电气控制系统为研究对象,利用可编程控制器(PLC)对联合收割机电气控制系统进行改进,以提高联合收割机运行效率和可靠性。通过对联合收割机的工作原理和液压作动系统进行分析,基于可编程控制器(PLC)进行联合收割机电气系统... 以联合收割机电气控制系统为研究对象,利用可编程控制器(PLC)对联合收割机电气控制系统进行改进,以提高联合收割机运行效率和可靠性。通过对联合收割机的工作原理和液压作动系统进行分析,基于可编程控制器(PLC)进行联合收割机电气系统整体设计,并对电气系统的运行效果进行测试分析。试验结果表明:系统运行可靠,能够获得良好的收割效果,可将收割损失率控制在2%以内,验证了系统运行过程稳定性。 展开更多
关键词 联合收割机 电气控制系统 可编程控制器 收割损失率
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