• Title/Summary/Keyword: Database Management Systems

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A Study on the Design of the Operator Training Simulator for Power Monitor and Control System in the Railway System (철도 전력관제시스템을 위한 운영자 훈련용 시뮬레이터 설계에 관한 연구)

  • Cho, Yoon-Sung
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.64 no.11
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    • pp.1631-1638
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    • 2015
  • This paper describes the design methodology of the operator training simulator for power monitor and control system in the railway system. In power system, the purpose of energy management system was to monitor, control, and analyze the performance of generation and transmission system based on H/W and S/W. Network analysis applications provide a clear picture of power system characteristics using state estimation, power flow and short circuit analysis. In this respect, the operator training system in the railway system should be equipped with the methodology of these systems. First, the proposed database structure in the railway system was introduced. Then the overall structure of operator training system based on railway analysis applications was proposed. Finally, a methodology to verify the performance of the developed applications was described.

Double-Version Graph Validation Scheme for Security Management in Database Systems (자료기지 보안 관리를 위한 이판 그래프 검증 기법)

  • 김남규;손용락;문송천
    • Proceedings of the Korean Information Science Society Conference
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    • 1999.10a
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    • pp.287-289
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    • 1999
  • 다등급 보안 자료기지 관리체계는 하위 등급의 자료에 대한 쓰기 연산 및 상위 등급의 자료에 대한 읽기 연산을 불허하여, 상위 등급의 자료가 하위 등급의 거래에 노출되는 것을 방지한다. 하지만, 전통적인 다등급 보안 자료기지 관리체계는 서로 상이한 등급간 거래의 공모로 생성될 수 있는 비밀 경로는 차단할 수 없다. 이러한 비밀 경로의 생성을 막기 위한 여러 연구가 다중 버전의 환경 및 제한된 버전의 환경 하에서 수행되어 왔다. 하지만 다중 버전에 기반한 기법은 상위 등급의 거래가 지나치게 오래된 버전의 자료를 읽을 뿐 아니라 버전 관리를 위하여 추가적인 부담이 요구된다는 단점이 있고, 제한된 버전에 기반한 기법은 항상 상위 등급 거래의 지연 및 철회를 강요한다는 단점이 있다. 본 논문에서는 제한된 버전 하에서 직렬화 가능성 그래프 검사 기법을 사용하여, 각 보안 등급간의 형평성을 높일 수 있는 비밀경로 생성 방지 기법을 제안한다.

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A Study on the Application of Virtual Manufacturing Technology for an Automotive Plant

  • Sohn, Chang-Young;Noh, Sang-Do;Hahn, Hyung-Sang;Lee, Chang-Ho;Hong, Sung-Won;Kim, Duck-Young
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.73.2-73
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    • 2001
  • Nowadays, one of the major technical issues in manufacturing is how to implement an virtual plant as an well-designed, integrated environment for sharing information and engineering collaboration among diverse engineering activities. The systematic approaches to make a virtual plant based on a 3-dimensional CAD, cell and line simulation, database and internet technologies are proposed in this paper. To do that, measuring and 3D CAD modeling technologies of many equipments, facilities and structures of the building are developed, effective management of information including models and related files in WWW environment is implemented, and precise simulations of unit cell and whole structured plant are performed. For the beginning of implementing a Virtual Automotive Plant, the Virtual Plant for the Body Shop of a Korean automotive company is constructed and implemented, Using this Virtual Plant ...

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Development for Database Synchronization Program Between Different Systems (전력계통 자료연계 DB동기화 프로그램 개발 활용)

  • Kim Kwang Ho;Cho Young Min;Lee Yun Ki;Lee Jin Su;Kim Tae Eon;Kim Yong Soo
    • Proceedings of the KIEE Conference
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    • summer
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    • pp.180-182
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    • 2004
  • 최근 전력산업은 전통산업으로 인식되었던 기존의 틀을 과감히 벗고 IT, NT 테크놀러지와의 기술융합을 통해 혁신과 발전으로 진일보하고 있다. 이와 함께 북미지역을 비롯하여 유럽에서 발생한 광역정전의 영향은 전력계통 안정운영의 중요성을 한층 고조시키고 있다. 이러한 패러다임의 변화로 이기종 전력시스템들이 네트워크로 상호 연결되어 전력계통 데이터의 시스템간 자료교환이 활발해 지고 있으며, 이에 따라 신속하고 정확한 데이터 연계의 중요성이 요구되고 있다. 본 논문에서는 현재 한국전력거래소에서 운영하고 있는 EMS(Energy Management System) 시스템의 데이터베이스와 이기종 시스템과의 데이터 송 수신시 필수요소인 자료연계 DB의 작성을 위해 자체 개발하여 활용중인 전력계통 자료연계 DB 동기화 프로그램을 통한 자동화 사례에 관해 소개하고자 한다.

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Petri Nets Modeling Using Relational Algebra (관계 대수를 이용한 페트리 네트의 모델링)

  • Young Chan Kim
    • Proceedings of the Korea Society for Simulation Conference
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    • 1992.10a
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    • pp.12-12
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    • 1992
  • This paper proposes an analysis method of Petri nets (PNs) using the relational algebra (RA). More specifically, we represent PNs in relations of the relational model. Based on such representation, we first develop an algorithms for analyzing properties of PNs, such as boundedness, conservation, coverability, reachability, and liveness. The advantage of this approach is as follows: First, the algorithms represented by RA can be easily converted to a query language such as SQL of the widely used, commercial relational database management systems (DBMSs). Second, we can alleviate the problem of state space explosion because relational DBMSs can handle large amounts of data efficiency. Finally, we can use the DBMS's query language to interpret the Petri nets and make simulation.

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Modeling of Petri Nets Using Relatinal Algebra (관계 대수를 이용한 페트리 네트의 모델링)

  • 김영찬
    • Journal of the Korea Society for Simulation
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    • v.1 no.1
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    • pp.37-47
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    • 1992
  • This paper proposes an analysis method of petri nets(PNs) using the relational algebra(RA). More wpecifically, we represent PNs in relations of the relational model. Based on such representation, we first develop an algorithm for generating reachability trees of PNs. we then develop an algorithm for generating reachability trees of PNs. We then develop algorithms for analyzing properties of PNs, such as boundedness, conservation, coverability, reachability, and liveness. The advantage of this approach is as follows: First, the algorithms represented by RA can be easity converted to a query language such as SQL of the widely used, commerical relational database management systems(DBMSs). Second, we can alleviate the problem of state space explosion because relational DBMSs can handle large amounts of data efficiently. Finally, we can use the DBMS's query language to interpret the Petri nets and make simulation.

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A Design of Integrated Manufacturing System for Compound Semiconductor Fabrication (화합물 반도체 공장의 통합생산시스템 설계에 관한 연구)

  • 이승우;박지훈;이화기
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.26 no.3
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    • pp.67-73
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    • 2003
  • Manufacturing technologies of compound semiconductor are similar to the process of memory device, but management technology of manufacturing process for compound semiconductor is not enough developed. Semiconductor manufacturing environment also has been emerged as mass customization and open foundry service so integrated manufacturing system is needed. In this study we design the integrated manufacturing system for compound semiconductor fabrication t hat has monitoring of process, reduction of lead-time, obedience of due-dates and so on. This study presents integrated manufacturing system having database system that based on web and data acquisition system. And we will implement them in the actual compound semiconductor fabrication.

Identification of Partial Discharge Defects based on Back- Propagation Algorithm in Eco-friendly Insulation Gas

  • Sung-Wook Kim
    • Journal of information and communication convergence engineering
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    • v.21 no.3
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    • pp.233-238
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    • 2023
  • This study presents a method for identifying partial discharge defects in an eco-friendly gas insulated system using a backpropagation algorithm. Four partial discharge (PD) electrode systems, namely, a free-moving particle, protrusion on the conductor, protrusion on the enclosure, and voids, were designed to simulate PD defects that can occur during the operation of eco-friendly gas-insulated switchgear. The PD signals were measured using an ultrahigh-frequency sensor as a nonconventional method based on IEC 62478. To identify the types of PD defects, the PD parameters of single PD pulses in the time and frequency domains and the phase-resolved partial discharge patterns were extracted, and a back-propagation algorithm in the artificial neural network was designed using a virtual instrument based on LabVIEW. The backpropagation algorithm proposed in this paper has an accuracy rate of over 90% for identifying the types of PD defects, and the result is expected to be used as a reference database for asset management and maintenance work for eco-friendly gas-insulated power equipment.

Design and implementation of unmanned payment and inventory management systems using RFID technology (RFID 기술을 이용한 무인 결제 및 재고 관리 시스템 설계 및 구현)

  • Jang, Eun-Gyeom;Kang, Eun-Bi;Jung, Gun-Young;Jung, Jee-Hwan;Lee, Tae-Hyun
    • Proceedings of the Korean Society of Computer Information Conference
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    • 2021.07a
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    • pp.515-516
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    • 2021
  • 본 논문은 대형 매장 및 편의점 등과 같은 상품의 구매와 판매가 이루어지는 시스템에서 RFID를 활용하여 무인 결제 서비스를 지원한다. 제안 기술은 사용자가 결제처리, 재고관리 기능을 갖는다. 결재 시스템은 상품 결재와 동시에 재고 관리가 가능하도록 설계하였다. 소비자의 입장에서는 편리하고 쾌적한 스마트 쇼핑 환경을 제공 받을 수 있고, 판매자 입장에서는 인건비 절감효과, 재고관리에 효율성과 편의성을 제공한다.

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Development of a Model for Managing Chemical Substances in Korea with Emphasis on Cleaning Solvents (우리나라의 화학물질 관리모델 개발: 세정용 유기용제를 중심으로)

  • Roh, Young-Man;Kim, Chi Nyon;Kim, Kang Yoon;Han, Jin Gu;Ko, Won Kyung;Yoon, Mi Youn;Park, Seoung-Hyun
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.10 no.1
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    • pp.179-207
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    • 2000
  • Hazardous organic solvents management as prescribed by presidential decree in Korea is reviewed. The status of import, manufacture, and circulation of organic solvents was investigated. Problems inherent in the management of organic solvents in the electroplating, metal degreasing, and dry cleaning industries were discussed. The chemical substance management system in Korea was compared to those of foreign organizations. A walk-through check list was developed and then used to assess the actual conditions and potential hazards of chemical substances in these industries. The questionnaire could be used to develop a chemical management system and protect workers from hazardous substances. Based on the results of the site survey, MSDSs were not integrated appropriately into the workers education and were not readily accessible to employees. In the case of the dry cleaning industry, the new dry cleaning solvent used as a substitute includes a lot of potentially hazardous organic solvents. This research is preliminary. It is recommended that a national survey be performed to better identify the current situation. Because chemical substances are regulated by thirteen laws in seven executive branches, management systems often overlap, resulting in ineffective control. Using the above results, a model for managing chemical substances was developed. This will more efficiently provide MSDS information to workers covered by the presidential decree and allow the construction of a management system database for better cooperation with the executive branches in Korea.

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