• Title/Summary/Keyword: Underground

Search Result 7,636, Processing Time 0.029 seconds

Design of Fault Location System for High Voltage Underground Power Cable (지중송전선 고장점 탐색 장치 설계)

  • Lee, Jae-Duck;Ryoo, Hee-Suk;Choi, Sang-Bong;Nam, Kee-Young;Jeong, Seong-Hwan;Kim, Dae-Kyeong
    • Proceedings of the KIEE Conference
    • /
    • 2006.10c
    • /
    • pp.603-605
    • /
    • 2006
  • To reduce inference of any power delivery failures in underground power cable, power system operators are trying to find effective way of finding fault location as soon as possible. But it is very difficult to find fault location exactly for underground power cable. We are developing fault location system for underground power cable which can detect its fault location exactly. This new system monitors current and voltage of underground power cable by using low voltage and current sensors and if there are any accidents, it records its transient signal. Fault location is calculated by analyzing recorded signal. To develop fault location system for power cable, we needed fault simulation system and we installed it physically and tested. In this rapers, we describe on describe of fault location system for underground power cable.

  • PDF

A Case Study on the Utilization of Underground Building (지중건축의 활용에 관한 사례연구)

  • Suh, Eung-Chul;Lim, Sang-Hoon;Jang, Moon-Seok;Yoo, Heon-Hyung
    • KIEAE Journal
    • /
    • v.1 no.1
    • /
    • pp.17-26
    • /
    • 2001
  • The purpose of this study is to develop an underground Building. Population tends to concentrate in large cities. In result, the cities lacks housings. Underground space may be a attractive space by being able to gain alternative energy and get a cheap site, protect environment at the same time. The earth or ground is a useful medium for a long-term heat source and storage of it's heat. Also the underground space has the status of stabilization, the lower heating load and the similar heat transfer coefficient of the inside wall surface comparing to that of residential space. Utilization of underground space has many advantages to cope with lack of building sites and energy conservation, etc. As a result, it is expected to provide a useful information for the practical use of Underground building.

  • PDF

Verification of Underground Distribution Line Modeling with Field Test (실증시험을 통한 지중배전선로 모델링 기법 검증 연구)

  • Yun, Chang-Sub;Lee, Jae-Bong;Kim, Byong-Suk;Lee, Jong-Beom
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.56 no.12
    • /
    • pp.2091-2097
    • /
    • 2007
  • This paper described the verification of modeling technique of underground distribution from comparison between field test and simulation. It needs more exact transient phenomenon analysis model to establish lightning protection of underground distribution line. Although, there were a lot of transient phenomenon researches, nobody could has verified the confidence of modeling from field tests in interior until now. So, simulation model verified field test is needed to analyse transient phenomenon of underground distribution system. The examination must be accomplished in many different condition before suggesting these verified analysis model. In this paper, the conditions were examined and the various data results on the different line composition was compared with the EMTP simulation, when the lightning impulse test was accomplished at underground distribution line. Also the value between field test and simulation was very closed and the method of modeling has demonstrated confidence, when the method is used to analyse domestic transient phenomenon of underground distribution.

Estimation of Risk from Air Pollution in the Underground Highway Proposed to Construct in Seoul, Korea

  • Lee, Ki-Young;Yukio-Yanagisawa
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.9 no.E
    • /
    • pp.397-400
    • /
    • 1993
  • The possible air pollution problems in a proposed underground highway are discussed using carbon monoxide (CO) as an indicator. Carbon monoxide concentrations in the underground highway depend on several factors, including the size of tunnel, the number of automobiles, the CO emission rate, and the tunnel ventilation rate. Using the estimated values, CO concentrations in the underground highway can be predicted. Without proper ventilation system, CO concentration in the underground highway can be dangerous level. However, the cost of operating the mandatory mechanical ventilation system may be tremendouslyy high and may be technically unrealistic to implement. If the underground highway is constructed with proper ventilation system, a continuous air pollution monitoring system with alarming function must be installed to alert personnel of serious air pollution built up in the underground highway. Traffic must be restricted, whenever the inside air pollution levels exceed agreed values. Short distances between evacuation exits are necessary for emergency situations or malfunction of ventilation system.

A Study on the Method to Predict Underground Temperature of the District without the Measured Data (측정 자료가 없는 지역의 지중 온도 예측 방법에 관한 연구)

  • Jeong, Soo-Ill
    • Journal of the Korean Solar Energy Society
    • /
    • v.23 no.2
    • /
    • pp.1-7
    • /
    • 2003
  • Due to the lack of fossil fuel the demand for the development of alternative energy is gradually growing. There are solar energy and underground energy as the alternative energies for housing. To use underground energy, we need some data on the underground temperature but the data are very rare in our country. So we need tools to calculate the underground temperature. In this paper a method to calculate the underground temperature is sought with the latitude, the level, and the distance from sea for the district without the measured data.

A Study of the movement pattern of pedestrian in the underground space and the factor of route choice and preference (지하공간의 보행자 이동패턴과 경로선택 요인에 관한 연구)

  • Park, Myeong-Hee;Jeon, Gyu-Yeob;Hong, Won-Hwa
    • Proceeding of Spring/Autumn Annual Conference of KHA
    • /
    • 2005.11a
    • /
    • pp.311-314
    • /
    • 2005
  • Our city structure is being complicated from the development of industry and the increase in population. It makes the ground space overcrowded, so underground space is systematized for use. Because this underground space has very complicated configuration, people have difficulty in finding the route in the underground space. Therefore It is demanded to comprehend configuration of the various space structure, predict pattern of the moving and analyze induction factor of the moving. When people are in the conflagration or dangerous situation, they are in the habit of using the route which they are used to go to and from. It is needed to analyze moving pattern of the pedestrian who usually use the underground space for the sake of dealing with conflagration in the underground space. Finally, this study suggested that general characteristic, distribution, moving route of the pedestrian and factors influencing that they choose the route which the research finds out.

  • PDF

Underground Storage of Food (농수산물 및 식품의 지하 저장)

  • 신희순;권광수
    • Tunnel and Underground Space
    • /
    • v.4 no.2
    • /
    • pp.192-200
    • /
    • 1994
  • Underground offers many advantages for storing agricultural and marine products. Since it is confined by thick walls of rock it is easy to control temperature and humidity and to achieve air and water tightness. Also, damages by rodents and insects could be avoided. Flexibility in choosing the location is another advantage that underground could offer. Consequently the goods could be stored near the big city to meet the demand change. Because of these advantages, many underground food storage facilities were built and operated successfully in U.S. and many Euroupean countries. On the other hand, there is no underground food storage facilities in Korea despite the need is growing rapidly. This paper describes the case studies of foreigh food storage and technologies related to food storage were analyzed and evaluated. Also performed is analysis of domestic technologies for construction and operation of underground food storage facilities to deduce the fields of studies that have to be conducted.

  • PDF

Improvement of Underground Waterproof for RC Structures (콘크리트 구조물의 지하방수 개선 방향)

  • 민병렬;김성옥;이문환;이장화;권기주
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 1994.04a
    • /
    • pp.249-253
    • /
    • 1994
  • Nowadays, utilization of underground space is increasing due to diversion of industry structures and development of urban transportation. To ensure the underground space as a living space, many problems have to be solved and one of them is ensurance of waterproof. As the foundamental study to improve the underground waterproof system for RC structures. This study investigates the underground environment, waterproof system and factors causing leakage and provides the diredtion of improvements.

  • PDF

The Factors Governing Envlronment and Safety in Underground Spaces (지하공간의 환경 및 안전관리 요소)

  • 김복윤
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 1993.10b
    • /
    • pp.133-162
    • /
    • 1993
  • The environment of underground spaces might be considered in view of working environment during the construction and living environment after completion of the construction work. For controlling environment of underground space, an appropriate measures have to be taken on the governing factors such as air flow, dust, gases, heat, radiation, noise, illumination and water. The more critical matter, in underground environmental point of view, is underground disasters such as fire, gas explosion and water inrush. This paper presents the general introduction of these factors mentioned above and some outcomes of research works as of now.

  • PDF

A Study on Structural Behavior of Underground Openings in Discontinuous Rock Masses (불연속면의 영향을 고려한 암반동굴의 구조거동연구)

  • 김선훈;최규섭;이경진;김진웅
    • Proceedings of the Computational Structural Engineering Institute Conference
    • /
    • 1991.04a
    • /
    • pp.20-25
    • /
    • 1991
  • In order to predict properly the effects of ground motion associated wi th earthquakes on underground radioactive waste disposal facilities, understanding of the structural behavior of an underground opening in discontinuous rook masses subjected to dynamic loadings is essential. Therefore, this paper includes literature review on computational models for discontinuous rook masses and on mathematical models for the structural analysis of underground openings. Then, structural analyses of underground openings using the distinct element computer program written for the static and dynamic analysis of discontinuous rook masses have been performed.

  • PDF