• Proceedings of the KIPE Conference
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• 2007.07a
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• pp.500-502
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• 2007

In case Power Line Communication (PLC) method is applied to a rainwater monitoring system, PLC module should be utilized. In this paper, PLC module using ST7538Q is implemented. The design rules of the IC peripheral circuit are explained in detail. The operation of the implemented PLC module is verified through the experimental results.

• Proceedings of the KIEE Conference
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• 2005.07b
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• pp.1550-1552
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• 2005

본 논문은 건설교통부의 국도 ITS에 도로변의 현장설비와 센터간 교통정보 수집체계에 전력선통신(Power Line Communication, PLC)망 적용에 관한 연구이다. 지능형교통시스템(Intelligent Transport System, ITS)에서 사용하고 있는 기존의 유 무선 통신망과 PLC망과의 통신 용량 및 속도, 구축 및 운영비용, 데이터 신뢰성 등을 비교하여 적용 가능성을 분석하였다.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.48-48
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• 2000

We developed a wireless communication system for multiple instrumentation system. The developed system has a function of remote instrumentation and PLC(Programmable Logic Controller) control. The system consists of CC(Control and Communication) protocol, wireless media access and physical media system. For multiple wireless communication, we propose a hub polling protocol based on master-slave control concept. To show the validity of the developed system, several experiments are illustrated.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.29 no.2
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• pp.365-375
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• 2019

A PLC (Programmable Logic Controller) is a highly-reliable industrial digital computer which supports real-time embedded control applications for safety-critical control systems. Real-time operating systems such as uC/OS have been used for PLCs and must meet real-time constraints. As PLCs have been widely used for industrial control systems and connected to the Internet, they have been becoming a main target of cyberattacks. In this paper, we propose an execution code sanitizer to enhance the security of PLC systems. The proposed sanitizer analyzes PLC programs developed by an IDE before downloading the program to a target PLC, and mitigates security vulnerabilities of the program. Our sanitizer can detect vulnerable function calls and illegal memory accesses in development of PLC programs using a database of vulnerable functions as well as the other database of code patterns related to pointer misuses. Based on these DBs, it detects and removes abnormal use patterns of pointer variables and existence of vulnerable functions shown in the call graph of the target executable code. We have implemented the proposed technique and verified its effectiveness through experiments.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.40 no.4
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• pp.282-290
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• 2003

AMR(Automatic Meter Reading) and RC(Remote Control) System have been researched from former several decade for a various power rate system, a efficient power service and rising of personal expenses, etc. But the existing AMR and RC System have disadvantage which are complex and high cost to install an individual communication network of electricity company. This paper proposed a new type of AMR and RC System using PLC with Web. and made components for proposal system. Most customer who live in apartment have an internet cable in the Republic of Korea. Therefore there is no more installation component for communication in proposal system at the apartment, except Web server system and PLC modem. so we made the PLC modem the digital watt-hour meter with a build in PLC modem and the software on server computer for establishing the proposal system.

• Journal of Institute of Control, Robotics and Systems
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• v.2 no.1
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• pp.53-59
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• 1996

An automatic verification method has been studied to determine the safety and operability of programmable logic controller (PLC) based systems. For the systematic and efficient verification, we have developed a conversion method from relay ladder logic (RLL) to the verification system description. RLL is a common representation used to document PLC programs for the sequential logic of the system such as the safety interlocks and the startup/shutdown procedures. Once the modules are developed, complex RLLs can be represented by the combination of modules. As a result we can verify complex PLC systems using the verification method including RLL modules. The developed modules are used to verify alarm systems and show that the method is valid.

• 한국정보통신설비학회:학술대회논문집
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• 2007.08a
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• pp.223-226
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• 2007

This paper first outlines the technology used in Power Line Communications(PLC) systems, and the political support being offered to the technology, from the point of view of its effect on electromagnetic compatibility (EMC). The radio spectrum needs protection from other interferers, and there is a regime in place to provide this interference avoidance/mitigation. Nevertheless, PLC has several features that mean that it is capable of creating such interference. These features are discussed, and some published field trial results are reviewed. Difficulties in achieving compatibility between the requirements for radio protection and the requirements for operation of the PLC system mean that there is no consensus as yet as to how PLC system components can be made compliant with EMC requirements. It is concluded that there is little prospect of an accommodation between the competing demands, so that if PLC is to become widespread it will be at the expense of the radio environment.

• Proceedings of the KIEE Conference
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• 1999.11c
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• pp.609-611
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• 1999

산업현장의 제어기들은 센서들로부터 수집된 다양한 형태의 신호들을 처리한다. 이 신호들은 고정된 값을 가지지 않고 물리적으로 변화하는 특성을 가진다. 이와 같이 변화하는 값을 처리하는 방법으로 다양한 형태의 연구가 진행되고 있고, 그 한 분야로 퍼지(Fuzzy)이론을 바탕으로 한 퍼지 제어 시스템에 대한 연구가 활발하게 진행되고 있다. Fuzzy PLC 시스템은 현재 초기단계 형태로 개발되어 사용되고 있으며 그 응용 방법도 조금씩 보급되고 있는 실정이다. 본 논문은 변화하는 값들에 대해 간결하고 적절한 제어를 수행 할 수 있는 기 개발된 Fuzzy PLC 시스템을 이용한 플랜트 제어에 대한 연구이다. 크레인(Crane) 제어용으로 사용한 Fuzzy PLC 시스템은 Moeller사의 FT4-400-MM2 PLC 모듈이다. 본 시스템을 이용하여 대상 플랜트인 크레인을 제어하는 퍼지 함수 로직을 개발하고, 입 출력 제어 프로그램 기법에 대하여 연구한다. 또한 퍼지 제어 시스템을 이용한 퍼지 제어 기법을 개발하는 과정에 대하여 소개한다. 결론적으로 Fuzzy PLC System 개발 및 응용 모델로서 제안하고자 한다.

• Biomolecules & Therapeutics
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• v.1 no.1
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• pp.121-124
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• 1993

To elucidate the effect of antipsychotics and antidepressants on phosphoinositide(Pl) second massenger system, we studied the dose-dependent inhibition of the phosphoinositide-specific phospholipase C(PLC) isozymes, ${\beta}_1,\;{\gamma}_1$ and${\delta}_1,$ by fluphenazine and haloperidol as antipsychotics, and amitriptyline, maprotiline and mianserin as antidepressants. All the antipsychotics and antidepressants tested showed inhibition on at least one of the PLC isozymes with $IC_{50}$ at the concentration between 25 and $250 {\mu}M.$ Maprotiline, mianserin and amitriptyline inhibited 80 to 90% of the activities of all three PLC isozymes at the concentration of $250{\mu}M,$ while haloperidol and fluphenazine inhibited PLC ${\beta}_1$ and${\gamma}_1$ But baclofen didn't inhibit any PLC isozyme. These results suggested that PLC isozymes are inhibited by antipsychotics and antidepessants even though the concentration is high, and these drugs may affect PI signal transduction system by direct inhibition of PLC isozymes.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.116-119
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• 2004

The existing monitoring and control systems of utility-pipe conduit (power tunnel, cable tunnel etc) have established communication lines using optical fiber, leaky coaxial cable (LCX), and several kinds of control cable. Due to the properties of the used media, the cost of equipment is considerably high and the maintenance of the system is difficult. Also, the term of carrying out is long so that the extension of the system is in difficulty. Now it is desirable to adopt Power Line Communication (hereinafter, PLC) technology in the monitoring and control systems and use the existing low-voltage power-line for lamplight as communication line. This will lead the reduction of the construction cost and the easy maintenance of the system. In this paper, we research the characteristics of PLC in conduit, design and manufacture the field test system, and analyze the performance of the system by field test. Then, we introduce the reliable monitoring and control system of utility-pipe conduit using PLC.