• Journal of the Korean Society of Safety
• /
• v.11 no.2
• /
• pp.150-159
• /
• 1996

In this paper, an A-team(Asynchronous Team ) based approach for Reactive power and volage control considering static security assessment in a power system with infrastructural deficiencies is proposed. Reactive power and voltage control problem is the one of optimally establishing voltage level given several constraints such as reactive generation, voltage magnitude, line flow, and other switchable reactive power sources. It can be formulated as a mixed-integer linear programming(MILP) problem without deteriorating of solution accuracy to a certain extent. The security assessment is to estimate the relative robustness of the system in Its present state through the evaluation of data provided by security monitoring. Deterministic approach based on AC load flow calculations is adopted to assess the system security, especially voltage security. A security metric, as a standard of measurement for power system security, producting a set of discrete values rather than binary values, is employed. In order to analyze the above two problems, reactive power/voltage control problem and static security assessment problem, in an integrated fashion for real-time operations, a new organizational structure, called an A-team, is adopted. An A-team is an organization for agents which ale all autonomeus, work in parallel and communicate asynchronously, which is well-suited to the development of computer-based, multi-agent systems for operations. This A-team based approach, although it is still in the beginning stage, also has potential for handling other difficult power system problems.

• The Plant Pathology Journal
• /
• v.20 no.1
• /
• pp.52-57
• /
• 2004

Sclerotinia sp. (isolate BWC98-105) causes stem blight and root rot in Leghum sp., and is presently being evaluated as a potential mycoherbicide for the control of Trifoliorium repens. Bioassays have shown that Sclerotinia sp. produces phytotoxic substance which is biologically active against T. repens. Two biologically active compounds, designated as compoundsI and II, were produced in vitro from the culture filtrate of BWC98-105 isolate Sclerotium sp. Compounds I and II were purified by means of liquid-liquid extraction and $C_{18}$ open column chromatography (300 ${\times}$ 30 mm, i.d). To determine the purity, the purified compounds were analyzed by RP-HPLC. The analytical RP-HPLC column was a TOSOH ODS-120T (150 ${\times}$ 4.6 mm i.d, Japan), of which the flow rate was set at 0.7 mL/min using the linear gradient solvent system initiated with 15 % methanol to 85 % methanol for 50 min with monitoring at 254 nm. Under these RP-HPLC conditions, compounds I and II eluted at 3.49 and 4.13 min, respectively. Compound II was found to be most potent and host specific. However, compound I had a unique antibiotic activity against phytopathogenic bacteria like bacterial leaf blight (Xanthomonas oryzae) on rice, where it played a less important role in producing toxicity on T. repens. No toxin activity was detected in the water fraction after partitioning with several organic solvents. However, toxin activity was detected in the ethyl acetate and butanol fractions. In the leaf bioassay using compound II, the disease first appeared within 4-5 h as water soaked rot, which subsequently developed into well-defined blight affecting the whole plant.

• Journal of the Korean Society of Industry Convergence
• /
• v.20 no.2
• /
• pp.177-186
• /
• 2017

With the latest developments in ICT(Information Communication Technology) technology, research on Intelligent Car, Connected Car that support autonomous driving or services is actively underway. It is true that the number of inputs linked to external connections is likely to be exposed to a malicious intrusion. I studied possible security issues that may occur within the Connected Car. A variety of security issues may arise in the use of CAN, the most typical internal network of vehicles. The data can be encrypted by encrypting the entire data within the CAN network system to resolve the security issues, but can be time-consuming and time-consuming, and can cause the authentication process to be carried out in the event of a certification procedure. To resolve this problem, CAN network system can be used to authenticate nodes in the network to perform a unique authentication of nodes using nodes in the network to authenticate nodes in the nodes and By encoding the ID, identifying the identity of the data, changing the identity of the ID and decryption algorithm, and identifying the cipher and certification techniques of the external invader, the encryption and authentication techniques could be detected by detecting and verifying the external intruder. Add a monitoring node to the CAN network to resolve this. Share a unique ID that can be authenticated using the server that performs the initial certification of nodes within the network and encrypt IDs to secure data. By detecting external invaders, designing encryption and authentication techniques was designed to detect external intrusion and certification techniques, enabling them to detect external intrusions.

• Journal of the Korea Society of Computer and Information
• /
• v.14 no.6
• /
• pp.33-40
• /
• 2009

In this thesis, for the assessment of software development process for project complexity and project size : one of digital watermarking algorithm is selected and examined. Digital watermarking provides a solution to illegal copying of digital contents and has many other useful applications, including web broadcast monitoring, transaction tracking, authentication, copy control and device control. This thesis focused on the method for customizing software development path, considering the project environments and characteristics. The selection standard of software development path is composed of process items, based on the ISO/IEC 15721 Information Technology Guide for ISO/IEC 12207 (Software Life Cycle Process) and ISO/IEC 15504 Information technology - Process assessment. To evaluate the algorithm, a system for selecting development path, which reflected algorithm, was examined.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2015.10a
• /
• pp.20-23
• /
• 2015

In ports of Korea, the marine traffic flow is congested due to a large number of vessels coming in and going out. In order to improve the safety and efficiency of these vessels, South Korea is operating with a Vessel Traffic System, which is monitoring its waters 24-7. However despite these efforts of the VTS (Vessel Traffic System) officers, marine accidents are occurring in their assigned districts. VTS Officers are controlling subjectively based on their experience due to no VTS guideline. On this paper, we listened to Busan VHF channel for 3days and applied to collision risk model. With collision risk model, We deducted a moment which advise or recommend to vessel in encounter situation, VTSO's career, day&night.. We suggested a collision risk value as guide line of VTSO's control time.

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2016.07a
• /
• pp.29-32
• /
• 2016

본 논문에서는 나로호(KSLV-I) 비행상태의 실시간 감시를 목적으로 국내에서는 처음 개발된 우주센터 원격수신자료전시시스템(EDS)의 구축과 운용을 소개한다. EDS는 우주센터 발사통제시스템의 주요 시스템 중 하나이고 그 역할은 위성발사체의 비행에 중대한 영향을 주는 주요정보(QLM)와 궤적정보(TSPI)를 수신하여 실시간으로 처리함으로써 탑재 서브시스템별 전문가들이 위성발사체의 비행 상태를 감시할 수 있도록 지원하는 것이다. EDS는 3회에 걸친 나로호 비행시험에서 그 역할에 따라 매회 8대가 운영되었으며 임무를 성공적으로 수행하였다. 본 시스템을 기반으로 추후 발전된 형태의 한국형발사체(KSLV-II) 비행상태의 실시간 감시시스템의 구축이 가능할 것으로 예상된다.

• Proceedings of the KIPE Conference
• /
• 2004.07b
• /
• pp.728-732
• /
• 2004

기존의 지하 공동구 감시 시스템은 광케이블, 누설 동축케이블(LCX), 각종 제어케이블을 사용하여 통신 선로를 구축하기 때문에 시설비가 대단히 고가이며, 여러 가지 통신선로의 이용에 따른 유지보수가 어렵고 시공기간이 길어 시설 확대에 어려움이 있었다. 따라서 통신케이블의 설치 없이 기존에 설치된 공동구의 전등용 저압 전력선을 통신선로로 그대로 이용할 수 있는 전력선 통신 기술을 적용하여 유지보수가 용이한 저비용의 지하 공동구 감시제어시스템을 개발하는 것이 바람직하다. 본 논문에서는 공동구에서의 전력선 통신의 특성을 조사, 시험시스템 설계${\cdot}$제작, 현장실증시험을 통한 성능시험 및 분석을 수행하여 전력선 통신을 적용한 안정적인 공동구 감시제어 시스템을 제안하고자 한다.

• Proceedings of the Korean Society for Agricultural Machinery Conference
• /
• 2002.02a
• /
• pp.389-394
• /
• 2002

1) HTST공정에 적합한 공정감시 및 제어알고리즘을 개발하였고, 일련의 모든 프로그램은 G언어의 일종인 Labview 5.1을 사용하였다. 프로그램상에는 온도, 압력, 유량을 표시하는 아날로그 및 디지털 창을 마련하여 장치내부의 상태를 쉽게 파악학 수 있도록 하였다. 2) 살균온도를 9$0^{\circ}C$로 설정하였을 때 온도제어 오차는 0.05$^{\circ}C$였으며 이것은 Negiz와 Cinar(1995)의 온도제어 오차 0.22$^{\circ}C$보다 정밀한 제어가 이루어짐을 알 수 있었다. 3), 운전중 원료의 과살균을 방지하지 하기 위해 각 각의 경우에 스팀온도를 제어하였고 목표온도까지 가열하기 위한 각 유량과 초기온도별 스팀온도를 구하였다. 4) 본 연구의 이 후 과제로는 유량의 변화에 따른 홀딩튜브의 길이와 살균시간의 상관관계를 규명하여 실제 HTST공정에 적용될 수 있는 수학적 모델링을 구현해야 할 것으로 생각된다.

• Proceedings of the KIEE Conference
• /
• 2007.07a
• /
• pp.973-974
• /
• 2007

최근 전기용품 안전기준(이하 K 기준)의 국제규격(이하 IEC 규격) 부합화에 따라 온도퓨즈(thermal-links)에 대한 노화시험(ageing test)이 중요한 성능평가항목으로 부각되고 있다. 특히, 50일 이상 소요되는 온도퓨즈의 노화시험을 하기 위해서는 규격에 적합한 온도상승률을 가지고, 용단시간 및 용단온도를 정확하게 측정할 수 있는 시스템이 구축되어야 하므로, 그 성능평가설비 또한 매우 중요하다고 할 수 있다. 본 논문에서는 온도퓨즈의 K 기준 및 IEC 규격을 분석하여 노화시험항목을 고찰하였으며, 온도퓨즈 노화시험설비 자동화시스템을 개발하여 국제적 수준의 성능평가기술 기반을 구축하였다. 이러한, 시험설비의 자동화시스템 개발은 성능평가기술을 향상시킬 뿐만 아니라 향후 시험기관의 국제적 위상 제고(提高)에 중요한 역할을 할 것으로 기대된다.

• Proceedings of the KIEE Conference
• /
• 2007.07a
• /
• pp.794-795
• /
• 2007

정부의 소형 열병합 보급정책의 확대에 따른 가스엔진 소형 열병합 시스템이 아파트 단지를 중심으로 보급되고 있으나 시스템 전체가 해외기술에 의존하고 있는 실정이며 기기의 국산화가 시급한 과제로 대두되고 있다. 본고는 에너지관리공단이 지원하는 소형 열병합 발전시스템 실용화 기술개발의 한 분야로 개발된 소형 열병합 발전시스템과 전체 설비를 감시 및 제어하기 위해 개발된 감시제어 시스템의 개발에 대해서 간략히 소개 하고자 한다.