• 한국전기전자재료학회논문지
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• 제30권4호
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• pp.253-257
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• 2017

Nowadays, it is increasingly important to detect whether cables are live for the operator's safety if there is a sudden power failure. It is especially hard to detect the electrical field of an underground line because of shielding. This paper on detection of live-line states in cables studied the detection characteristics of the change in the magnetic field and axis as the frequency, voltage, and distance at the same load are changed using 3 axes. A search coil type was used as a magnetic field sensor with non-contact. We found that magnetic fields decrease proportionally to the square of the distance and the decrease of rated voltage with load effected to magnetic field. The magnetic field was detected by 3-axis sensors given correct proximity, but appeared as noise components beyond a distance of 2 cm.

• 한국GIS학회:학술대회논문집
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• 한국GIS학회 2008년도 공동춘계학술대회
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• pp.227-231
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• 2008

최근 국내에서 USN(Ubiquitous Sensor Network) 연구가 활성화 되면서 GIS 분야에서도 USN을 연동한 실시간 GIS 시스템이 구축되고 있다. GIS 분야 중 지하시설물은 그 중요성에 비해 관리 감독의 어려움에 의해 정량적 분석이 어려운 실정이다. 본 연구에서는 지하시설물을 획기적으로 정밀하게 관리 감독할 수 있는 UFSN(Underground Facility Sensor Network) 기반 지하시설물 관리시스템을 구축하기에 앞서 요구되는 지하시설물 관리데이터를 분석하였다. 또한 이 관리데이터를 구조화하는데 필요한 메타데이터를 USN 메타데이터 표준과 국토해양부 3차원 공간정보 메타데이터 표준을 조합하여 지하시설물 관리시스템에 필요한 메타데이터로 분류하였고, 분류된 메타데이터를 작성할 수 있는 지하시설물 메타데이터 편집도구를 개발하였다. 본 연구에서 제시한 UFSN 기반 지하시설물 메타데이터는 개발된 편집도구에 의해 작성되어 실제 관리시스템에 적용될 예정이며, 향후 USN 기반 GIS 시스템 개발에 크게 기여할 수 있을 것으로 기대된다.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2001년도 춘계학술대회 논문집
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• pp.213-218
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• 2001

These days, corrosion condition of a underground objects is measured by the electric potential between the subject and ground. But this method is implemented by means of manual work with analog voltmeter, which is uneconomic and inefficient. So, We developed real-time On-Line cathodic protection monitoring system that is able to detect corrosion potential conditions of metal objects or various steel structures in the ground continuously, display them with the graphic screen, construct a database, and analyze them simultaneously. Since the data of corrosion and corrosion protection of all underground objects is processed automatically, not manually in this system, It is possible to reduce the manipulated error, and perform precise safety management, maintenance and inspection. As as result, this system can not only guarantee long-life operation, reduction of manpower and cost, but prevent large accidents in advance.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1997년도 봄 학술발표회 논문집
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• pp.79-86
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• 1997

In this study, pre-postprocessing toolbox is developed to perform elasto-plastic analyze of underground structures with transient ground water flow. This toolbox is composed of three modules. The first is the data input processor for the structural analysis. The preprocessing Is using GUI (Graphic User Interface), which is consist of dialog box, pull down, and short-cut icon, etc. The second is the structural analysis module. The analysis is based on the elasto-plastic finite element method involving additional options such as ground excavation effect, transient ground water flow, and rock bolts behavior. The last is the postprocessing module. The postprocessing is able to verify the result of the structural analysis by the graphical simulation which visualizes the element mesh, the node displacements, the element stress states, the stress contour, the ground water surface, and the rock bolt stresses. Since various options are considered separately in this toolbox, it is easy to modify the module of each processing, and to update other functional modules for the given analysis conditions.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제55권12호
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• pp.597-600
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• 2006

When the energy of the nanoseconds high voltage pulse with hundreds picoseconds of the pulse rise time is emitted into the free space via an antenna, an ultra wide band electromagnetic wave is generated. This electromagnetic wave is expected to be used in transmitting vast amount of informations to far distance, high performance radars, post-packaging pasteurization of food, the detection of underground buried objects, searching of underground water veins or caves, the treatment of waste water or polluted gases and so forth. Additionally, this technology can be used in EMI(electromagnetic interference) evaluation of measuring instruments or printed circuit boards.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 1997년도 추계학술발표회논문집
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• pp.74-77
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• 1997

As underground distribution systems to be operated in downtown have more merits than overhead distribution system, underground distribution systems are being increased. But when pad-mounted transformers have troubles, reptures and fires can be occurred. We think that this makes accidents and power failures of bulidings and generates malaise and a great economic loss. In order to increase the reliability of pad-mounted transformers, we have investigated transformers and understood their failure mechani는. Therefore, we would have objectives and necessities of this study to improve quality and operating condition and install switches to be able to check and maintain transformers and optimize protection devices and increase cooling effect in pad-mounted transformers.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집
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• pp.52-56
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• 2001

Experiments of 2 type on insulating compounds accomplished to change PVC using in URD(Underground) power cable jacketing. one was DB(Dielectric Breakdown) test on the pure base resins and the others were WVT(Water Vapor Transmission) test on the compounds which contained C/B(Carbon Black), anti-oxidant to base resin. a kind of specimens made by pressing to resin of pellet or lump form was HDPE(High Density Polyethylene), MDPE(Medium Density Polyehylene), LDPE(Low Density Polyethylene), LLDPE(Linear Low Density Polyethylene), PVC(Polyvinyl Chloride). As a results of AC DB and WVT test, we saw that strength of Insulation was HDPE> LLDPE = MDP E> LDPE and WVT ratio was HDPE

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 A
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• pp.394-396
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• 2004

In order to reduce the sheath circulating current, same arrangement and balanced length of cable are required for the underground cable system. But practically, changing the whole arrange of cable which is already constructed is impossible. Therefore, It is necessary to apply the restraining-unit of sheath circulating current at the cross-bonding wire of insulated joint because the impedance of restraining-unit is able to reduce sheath circulating current at a normal condition. Even at a transient state, the restraining-unit must maintain electrical and mechanical characteristics. In this paper, the features of restraining-unit developed by LG Cable as well as the electrical test results are described. It proves that the restraining-unit is applicable to the underground cable system where sheath circulating current rises.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2019년도 추계 학술논문 발표대회
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• pp.237-238
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• 2019

As part of the development of building technology to improve the living performance closely related with lifestyle to Realize the Housing Welfare, the standard manual for the prevention and maintenance of water leaks in the underground structures of apartment buildings consists of Part 1 and Part 2. This study further covered the maintenance plan and inspection carried out in Part 1.

• 한국터널지하공간학회 논문집
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• 제15권6호
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• pp.613-623
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• 2013

현재 국내 석회석광산은 개발 방식 및 특성에 따라 환경적, 사회적, 경영적 측면에서 다양한 문제 등을 내포한 채 운영되고 있다. 따라서 최근에는 이 같은 문제점들을 저감하고 지속가능한 광산개발을 위하여, 갱내채광 혹은 시설물 갱내화 등 다양한 노력이 계속되고 있다. 이러한 노력은 기존의 광산개발 공간 외에 새로운 지하대형공간의 생성을 유발하기 때문에, 작업자 및 시설물의 안전성확보를 위하여 발생 가능한 다양한 종류의 리스크에 대한 재난관리 필요성이 제기되고 있다. 본 연구에서는 지하대형공간을 구축하고 시설물을 갱내화하여 본격가동을 앞둔 석회석광업현장의 작업자들을 대상으로 설문조사를 실시하여 리스크 위험도평가 및 업무영향력분석 후 재난관리를 위한 업무우선순위를 도출하였다. 그 결과, 대상 현장의 경우 파분쇄 및 분립선별공정에서 안전수칙 불이행으로 인한 리스크에 대하여 위험도가 가장 높은 것으로 나타났다. 또한, 이 리스크에 대한 재난발생시 업무연속성 유지를 위한 영향력을 분석결과 우선적으로 갱내외의 연계작업이 원활하게 이루어지도록 해야 하는 것으로 나타났다.