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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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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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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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Research on rapid development platform of PLC control system 被引量:3
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作者 王兴 Tang Xianwei +1 位作者 Dong Zengshou Zhen Liaomo 《High Technology Letters》 EI CAS 2021年第2期210-217,共8页
In the field of industrial process control,a fast-development platform for programmable logic controller(PLC)systems is designed in order to solve two main problems of rapid development of PLC control system and progr... In the field of industrial process control,a fast-development platform for programmable logic controller(PLC)systems is designed in order to solve two main problems of rapid development of PLC control system and programmability of controlling software.In the aspect of design,the platform is composed of hardware controlling and software monitoring and is taking industrial computer as the core.Under the Windows environment,the platform establishes the control instruction set,develops the configuration function and visual programming function of the monitoring software and it integrates PLC controller based on Visual Basic software.In order to achieve the function of data monitoring,it has realized the serial communication between computer and PLC by using RS-485 and RS-232 serial ports line communication.The platform designs the intelligent instruction scheduling strategy by studying the encoding and decoding rules of the communication instruction set.It proposes a method for rapidly developing control programs by adopting the expert control mode,which enables clients to develop and modify programs conveniently by importing instructions in a non-coded manner.After experimental testing,the platform is proved successful achieving both the rapid development of PLC control system and the rapid modification of monitoring software. 展开更多
关键词 programmable logic controller(PLC) rapid development instruction set instruction scheduling expert control
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The Designed Operation of the Machine Control System on HL-2A Tokamak 被引量:1
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作者 李强 樊明杰 +4 位作者 宋显明 王明红 唐芳群 罗萃文 袁保山 《Plasma Science and Technology》 SCIE EI CAS CSCD 2005年第5期2985-2988,共4页
The Ethernet and field-bus communications are used in the machine control system (MCS) of HL-2A. The control net, with a programmable logic controller (PLC) as its logic control master, an engineering control mana... The Ethernet and field-bus communications are used in the machine control system (MCS) of HL-2A. The control net, with a programmable logic controller (PLC) as its logic control master, an engineering control management station as its net server, and a timing control PC connected to a number of terminals, flexibly and freely transfers information among the nodes on it with the Ethernet transmission techniques. The PLC masters the field bus, which carries small pieces of information between PLC and the field sites reliably and quickly. The control net is connected into the data net, where Internet access and sharing of more experimental data are enabled. The communication in the MCS guarantees the digitalization, automation and centralization. Also provided are a satisfactory degree of safety, reliability, stability, expandability and flexibility for maintenance. 展开更多
关键词 COMMUNICATION programmable logic controller (PLC) machine control system HL-2A tokamak
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Automation Forage Burdening System Based on PLC
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作者 LIU Da-ming YU Cai HE Ping 《Animal Husbandry and Feed Science》 CAS 2011年第6期38-41,共4页
According to the demands for rapid and accurate burdening system, an automation forage burdening system was designed using a programmable logic controller (PLC) as the main controller. The communication between PLC ... According to the demands for rapid and accurate burdening system, an automation forage burdening system was designed using a programmable logic controller (PLC) as the main controller. The communication between PLC and force control was achieved by485 bus. This system have many functions such as recipe setup, burdening control, feed mixture, report printing, and remote alarm. The remote surveillance and control of burdening system were realized. The practice shows that the system had high precision and short cycle, and great control effect was obtained. 展开更多
关键词 Programmable controller Burden system Configuration software Automation control
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A Control System of Material Handlingin FMS
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作者 何永义 郭锡章 《Advances in Manufacturing》 SCIE CAS 1997年第1期55-58,共4页
The design of a control system for the material transport as used in gear-box flexible manufacturing system is presented in this paper. The scope of investigation covers material transport control, automatic vehicle, ... The design of a control system for the material transport as used in gear-box flexible manufacturing system is presented in this paper. The scope of investigation covers material transport control, automatic vehicle, material exchange station, multi-storeyed warehouse system, NC and CNC machines and host computer etc. The paper describes the transport control system and its design, and briefly describes the communication among devices and warehouse access principles. 展开更多
关键词 flexible manufacturing system (FMS) VEHICLE computer integrated manufacturing (CIM) programmable logic controller (PLC)
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FLOOD CONTROL PROGRAMME IN BANGLADESH
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作者 Wu Bingfang, Xia Fuxiang (National Lab. of Environmental & Resources Information System) (Institute of Geography, Chinese Academy of Sciences) 《遥感信息》 CSCD 1990年第A02期49-50,共2页
Bangladesh locates in lower reach of Ganges-Brahmaputra-Meghma, Bengal delta. Bangladesh is a land of rivers and heavy monsoon rains. Every year during monsoon period (May-September)the country floods of verying magni... Bangladesh locates in lower reach of Ganges-Brahmaputra-Meghma, Bengal delta. Bangladesh is a land of rivers and heavy monsoon rains. Every year during monsoon period (May-September)the country floods of verying magnitude, it causes damages to crops, properties, infrastructures, etc. and ultimately affects the economy development of the country. Banglandesh flood has some features given below: 1. The excessive rainfall over the vast catchment area of the river is the main cause of flood in Bangladesh, but 90% of the flood carried by rivers come from outside the country, i.e. regional countries, India, Nepal, 展开更多
关键词 FLOOD BA GIS FLOOD CONTROL programme IN BANGLADESH
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Identifying and Verifying Vulnerabilities through PLC Network Protocol and Memory Structure Analysis 被引量:2
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作者 Joo-Chan Lee Hyun-Pyo Choi +4 位作者 Jang-Hoon Kim Jun-Won Kim Da-Un Jung Ji-Ho Shin Jung-Taek Seo 《Computers, Materials & Continua》 SCIE EI 2020年第10期53-67,共15页
Cyberattacks on the Industrial Control System(ICS)have recently been increasing,made more intelligent by advancing technologies.As such,cybersecurity for such systems is attracting attention.As a core element of contr... Cyberattacks on the Industrial Control System(ICS)have recently been increasing,made more intelligent by advancing technologies.As such,cybersecurity for such systems is attracting attention.As a core element of control devices,the Programmable Logic Controller(PLC)in an ICS carries out on-site control over the ICS.A cyberattack on the PLC will cause damages on the overall ICS,with Stuxnet and Duqu as the most representative cases.Thus,cybersecurity for PLCs is considered essential,and many researchers carry out a variety of analyses on the vulnerabilities of PLCs as part of preemptive efforts against attacks.In this study,a vulnerability analysis was conducted on the XGB PLC.Security vulnerabilities were identified by analyzing the network protocols and memory structure of PLCs and were utilized to launch replay attack,memory modulation attack,and FTP/Web service account theft for the verification of the results.Based on the results,the attacks were proven to be able to cause the PLC to malfunction and disable it,and the identified vulnerabilities were defined. 展开更多
关键词 Industrial control system programmable logic controller CYBERSECURITY network protocol VULNERABILITY
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基于PLC和变频器技术在制冷压缩机电机正反转寿命试验装置的应用 被引量:2
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作者 王晓光 袁旭东 +3 位作者 昝世超 周俊海 孙云 黄静 《制冷与空调》 2022年第5期47-52,72,共7页
制冷压缩机电机正反转寿命试验是压缩机电机出厂前所必需的环节。为解决传统压缩机电机正反转试验装置中设备易损坏,数据采集易出现误差以及功能单一,不易控制的不足,文章设计了基于PLC、触摸屏和变频器技术的制冷压缩机电机正反转寿命... 制冷压缩机电机正反转寿命试验是压缩机电机出厂前所必需的环节。为解决传统压缩机电机正反转试验装置中设备易损坏,数据采集易出现误差以及功能单一,不易控制的不足,文章设计了基于PLC、触摸屏和变频器技术的制冷压缩机电机正反转寿命试验装置,详细介绍了该装置的PLC控制原理及程序流程。并将其进行了实际应用对比,测试结果表明:该试验装置具备能够长期运行,采集数据稳定良好,功能多样,操控简单等优势,并提高了此类试验装置的安全性。 展开更多
关键词 PLC(Programmable Logic Controller) 电机正反转 试验装置 触摸屏 变频器
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Synchro Controller of Radar on FPGA
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作者 Jiang Tie-zhen, Shi Zhen-hua, Wu Shi-caiSchool of Electronic Information, Wuhan University, Wuhan 430072,Hubei, China 《Wuhan University Journal of Natural Sciences》 EI CAS 2003年第02A期409-413,共5页
This paper mainly represents the realization of synchro controller based on the programmable logic devices FPGA by request of HF ground wave radar synchro controller under the instance of making the best of the virtue... This paper mainly represents the realization of synchro controller based on the programmable logic devices FPGA by request of HF ground wave radar synchro controller under the instance of making the best of the virtues of FPGA. This design introduces the data communication between PC and synchro controller by PC Bus, which can carry the synchronous signals parameters to RAM of synchro controller, then according to the theory that the result of comparing counter value with signals parameters is the needed wave, we produce all waves HF ground wave radar needs, moreover all waves are produced time-sharing in order to save resources. 展开更多
关键词 Data communication systems Field programmable gate arrays Programmable logic controllers SYNCHRONIZATION
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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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Design and Development of Mechatronic Application in Agricultural Irrigation Device
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作者 Mohd Hudzari Razali Syazili Roslan +1 位作者 Abdul Ssomad Mohd Abd Halim Hayan Basit 《World Journal of Engineering and Technology》 2016年第3期450-459,共11页
In order to help the small-scale farmer, an automatic irrigation control system was proposed. This system will provide an irrigation system that will ease the burden of the citizen to take care of the plant. This syst... In order to help the small-scale farmer, an automatic irrigation control system was proposed. This system will provide an irrigation system that will ease the burden of the citizen to take care of the plant. This system will run automatically by referring to the time set by the user. As the name itself is a water control system, this system will only start irrigating when the time set triggered the water control level for the plant to grow healthily. It will automatically stop when the timer is off (1 hour). The brain of the system is the PLC (Programmable Logic Controller). This is the place where all the activities are done. The irrigation will be provided by a pump that is also connected to the microcontroller. The pump will be activated until the timer has reached its time set. This system will continue running until the user presses the OFF button. 展开更多
关键词 Irrigation system Water Control system PLC (Programmable Logic Controller)
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一种用于精密铸造工艺的树脂模具高效多功能固化设备的开发与应用
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作者 潘浩星 《模具技术》 2022年第5期1-5,共5页
开发了一种基于stereo lithography appearance(SLA)光固化增材制造技术的、用于精密铸造领域树脂模具制作的后处理高效多功能固化设备。通过对核心机械结构的全新设计和加工工艺的深入探究,实现了可变循环散热、可变紫外功率、可变速... 开发了一种基于stereo lithography appearance(SLA)光固化增材制造技术的、用于精密铸造领域树脂模具制作的后处理高效多功能固化设备。通过对核心机械结构的全新设计和加工工艺的深入探究,实现了可变循环散热、可变紫外功率、可变速固化、可变固化时间、舱门互锁等多项新功能。以programmable logic controller(PLC)和human machine interface(HMI)为中央控制器和人机交互平台,通过图形化界面编程实现了一键固化、个性化参数匹配、温差限值安全锁定等控制功能。最后通过多组目标件测试及数据对比,验证了设备具有固化目标高质量、固化过程高效率、界面操作简便、使用过程高安全等特性。其作为高效多功能的SLA光固化树脂模具后处理核心设备,具有很高的使用和推广价值。 展开更多
关键词 精密铸造 programmable logic controller(PLC) human machine interface(HMI)
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Multifunction Plasma Arc Equipment
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作者 Li Jinglong, Tian Li, Lin Qiansheng Department of Material Science and Engineering Northwestern Polytechnical University, Xi′an 710072, P.R.China 《International Journal of Plant Engineering and Management》 1997年第3期36-40,共5页
A new type of plasma arc equipment with four functions including plasma arc welding, cutting, spraying and a surfacing process was designed and manufactured. To obtain good processing stability and multifunction integ... A new type of plasma arc equipment with four functions including plasma arc welding, cutting, spraying and a surfacing process was designed and manufactured. To obtain good processing stability and multifunction integration, a silicon controlled rectifier (SCR), and the programmable controller (PC) were introduced. The operation of this new machine shows that it has the advantage of simple circuit design, flexible control pattern, low fault rate and easy maintenance. 展开更多
关键词 plasma spraying plasma welding plasma cutting plasma surfacing Programmable Controller (PC) Silicon controlled Rectifier (SCR)
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Design of transfer device for magnetic thin sheet material
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作者 Liu Can Zou Congcong +3 位作者 Huang Blngshun Zhang Li WeiZhenchun Jin Aimin 《Computer Aided Drafting,Design and Manufacturing》 2016年第4期48-51,共4页
In order to realize the processing and retrieval of magnetic thin sheet materials in industrial production, this paper proposed a kind of transfer device for magnetic thin sheet raw material, which uses rodless cylind... In order to realize the processing and retrieval of magnetic thin sheet materials in industrial production, this paper proposed a kind of transfer device for magnetic thin sheet raw material, which uses rodless cylinders as the main motive device and the programmable logic controller (PLC) to achieve the required functions, and applies the finite element analysis method to analyze its main components in the end of the design. 展开更多
关键词 programmable logic controller control material transfer finite element analysis
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PMAC-based Tracking Control System for 8-axis Automated Tape-laying Machine 被引量:11
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作者 Liu Lin Li Yong Wen Liwei Xiao Jun 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2009年第5期558-563,共6页
This article introduces a computer numerical control (CNC)-based open hardware architecture system to realize the special functions of automated tape-laying (ATL) in a numerical control system. It associates a pro... This article introduces a computer numerical control (CNC)-based open hardware architecture system to realize the special functions of automated tape-laying (ATL) in a numerical control system. It associates a programmable multi-axis controller (PMAC) as the motion control unit with programmable numerical controllers (PCL-725, PCL-730) for on-off control. To bring about synchronized movements of the main 5-axis tape-laying head system and the 3-axis ultrasonic tape-cutting sub-system, the tracking-control method associated with time-based mode attributed to PMAC is applied in different cases. In addition, with the goal of realizing real-time tasks in the software system such as synchronizing motion control and on-off control, the real-time Win 2000 system is adopted. As a device driver for PMAC and PCL, a user graphical interface and a numerical control program interpretation module are also designed. This system is helpful to solve complicated problems in designing numerical controls for ATL such as ensuring high requirements for precise machine control and synchronization of motion control and on-off control. 展开更多
关键词 automated tape-laying tape-cutting programmable multi-axis controller on-off control systems tracking control
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The machine protection system for CSNS 被引量:1
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作者 Kang Mingtao Zhang Yuliang +6 位作者 Jin Dapeng He Yongcheng Zhan Mingchuan Zhu Peng Wu Xuan Guo Fengqin Wang Lin 《Radiation Detection Technology and Methods》 CSCD 2021年第2期273-279,共7页
Background The China Spallation Neutron Source(CSNS)accelerator consists of an 80 MeV H-LINAC,a 1.6 GeV rapid cycling synchrotron(RCS)and two beam transport lines.The uncontrolled beam may permanently damage the compo... Background The China Spallation Neutron Source(CSNS)accelerator consists of an 80 MeV H-LINAC,a 1.6 GeV rapid cycling synchrotron(RCS)and two beam transport lines.The uncontrolled beam may permanently damage the components or lead to very high residual radiation dose along the beam line.So the equipment protection must be deliberately designed and implemented.Purpose The machine protection system(MPS)protects components from being damaged by the beam.The response time requirement for the CSNS MPS is less than 20 ms,so the PLC(programmable logic controller)was adopted to implement the interlock logic.Methods The MPS was implemented as a two-tier architecture system,and developed through utilizing PLC and Experimental Physics and Industrial Control System(EPICS)software toolkits.The application logic was taken into careful consideration during the implementation stage.An embedded CPU module can function as an IOC accessing PLC I/O modules through the sequence CPU,with an embedded Linux operation system.Results The interlock logic and heartbeat functions were tested with all functions ok.Time consumption has been measured thoroughly since the important requirement,which is around 15 ms to stop the beam.Conclusions MPS was completed in Sep.2017 and then put into operation.It has been operating smoothly for more than 3 years.MPS has played an important role in every stage of CSNS’s commissioning and operation and achieved high reliability during the user’s experiment operation.The accelerator recently runs stably with low equipment failure. 展开更多
关键词 China Spallation Neutron Source Machine protection system Experimental physics and industrial control system Programmable logic controller
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The Electrical Control System PLC Transformation of The XA6132 Milling 被引量:1
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作者 XU Liang-xiong 《International Journal of Plant Engineering and Management》 2013年第4期249-254,共6页
For the electrical control system of XA6132 milling machine circuit complexity, reliability and flexibility, high failure rate. Mitsubishi FX2N-40MR programmable controller is used to improve the performance and effic... For the electrical control system of XA6132 milling machine circuit complexity, reliability and flexibility, high failure rate. Mitsubishi FX2N-40MR programmable controller is used to improve the performance and efficiency of the entire electrical control system by technological transformation. Mitsubishi FX2N-d0MRPLC on electrical control system transformation can expand link to the technological transformation of the similar equipments. 展开更多
关键词 Mitsubishi FX2N-40MR programmable controller XA6132 milling machine Electrical control sys-tem transformation PLC ladder
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Governance of tuberculosis control programme in Nigeria
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作者 Daniel Chukwuemeka Ogbuabor Obinna Emmanuel Onwujekwe 《Infectious Diseases of Poverty》 SCIE 2019年第3期96-96,共1页
Background:The role of governance in strengthening tuberculosis(TB)control has received little research attention.This review provides evidence of how institutional designs and organisational practices influence imple... Background:The role of governance in strengthening tuberculosis(TB)control has received little research attention.This review provides evidence of how institutional designs and organisational practices influence implementation of the national TB control programme(NTP)in Nigeria.Main text:We conducted a scoping review using a five-stage framework to review published and grey literature in English,on implementation of Nigeria's NTP and identified themes related to governance using a health system governance framework.We included articles,of all study designs and methods,which described or analysed the processes of implementing TB control based on relevance to the research question.The review shows a dearth of studies which examined the role of governance in TB control in Nigeria.Although costed plans and policy coordination framework exist,public spending on TB control is low.While stakeholders'involvement in TB control is increasing,institutional capacity is limited,especially in the private sector.TB-specific legislation is absent.Deployment and transfer of staff to the NTP are not transparent.Health workers are not transparent in communicating service entitlements to users.Despite existence of supportive policies,integration of TB control into the community and general health services have been weak.Willingness to pay for TB services is high,however,transaction cost and stigma among patients limit equity.Effectiveness and efficiency of the NTP was hindered by inadequate human resources,dilapidated service delivery infrastructure and weak drug supply system.Despite adhering to standardized recording and reporting format,regular monitoring and evaluation,revision of reporting formats,and electronic data management system,TB surveillance system was found to be weak.Delay in TB diagnosis and initiation of care,poor staff attitude to patients,lack of privacy,poor management of drug reactions and absence of infection control measures breach ethical standards for TB care.Conclusions:This scoping review of governance of TB control in Nigeria highlights two main issues.Governance for strengthening TB control programmes in low-resource,high TB burden settings like Nigeria,is imperative.Secondly,there is a need for empirical studies involving detailed analysis of different dimensions of governance of TB control. 展开更多
关键词 NIGERIA TUBERCULOSIS Control programme GOVERNANCE Scoping review
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