• Title/Summary/Keyword: earth systems

Search Result 1,295, Processing Time 0.032 seconds

Evaluation on the Performance of Design Parameters in Earth Tube System (지중튜브시스템 주요 설계 변수의 성능 평가)

  • Hwang, Yong-Ho;Hwang, Seok-Ho;Choi, Jeong-Min
    • Journal of the Korean Solar Energy Society
    • /
    • v.36 no.3
    • /
    • pp.87-94
    • /
    • 2016
  • Earth tube system can be installed in many ways. However, performance data on earth tube system is still insufficient. Therefore, in this study seven design parameters of earth tube systems were chosen such as underground earth tube length, depth, tube thermal conductivity, thickness, radius, soil conditions, and fan type. And the change effects in the values of the seven parameters on earth tube exit temperatures and heat transfer rate were examined through Energyplus simulations.

Interference Coefficient of X axis for Electrodes using Variation of Plural Earth Electrodes (복수접지극의 변화에 따른 전극의 X축 간섭계수)

  • Kim Sung Sam;Kim Ju Chan;Song Won Pyo;Koh Hee Seog
    • Proceedings of the KIEE Conference
    • /
    • summer
    • /
    • pp.449-451
    • /
    • 2004
  • In the building, there are a lot of electricity, electrodes, and communication equipment. Many of those equipment needs to earthing. Naturally, the earth electrodes are constructed in the site of a building. In such a situation, when electric current flows into a certain earthing system the potential of other earthing systems rises. That is, the potential interference will take place between the earth electrodes. The conventional study has been considered by only the relation of the distance between the earth electrodes using the potential distribution formula of earth surface. However, it is necessary to inquire strictly, taking the surface potential of electrodes by electrode form into consideration. In this paper, basic formula is deduced on the basis of both electrodes surface potential of earth electrode as a source of the potential interference and earth electrode which receives the potential interference.

  • PDF

Analysis on Coring Earth Electrode in Progress of Time (코아링 접지전극의 경년변화 해석)

  • Oh, Seong-Bo;Kim, Se-Ho;Kim, Ho-Chan;Boo, Chang-Jin;Ahan, Jae-Hyun;Ko, Seoung-Min;Ko, Young-Soo
    • Proceedings of the KIEE Conference
    • /
    • 2006.07e
    • /
    • pp.89-90
    • /
    • 2006
  • Recent earth systems not only make earth resistance decreased by installing earth electrode but also are demanded by earth construction for the protection of human life and equipments through total investigation about circumstances. Layer constructions in Jeju island consist of multi-layer of scoria, rocks and shale except clay layers on the surface, which needs the construction of the coring earth electrode suitable in the condition of the area. For this reason, we've used the coring earth electrode. But the coring earth electrode is expected to slow down the performance of this equipment according to the progress of time changing the effects. It is also applied for the stability of earth system construction and management after the construction work analyzing the condition of the earth system. Therefore, this is actually focused on the analysis on measuring the earth resistance and the soil resistivity that cover the range where the remarkable contrast can be expected to be seen in the layer structures.

  • PDF

Palaeodepositional Environment of the Cretaceous Hampyeong Basin, Southwestern Korea (한반도 남서부 중생대 백악기 함평퇴적분지의 고퇴적환경연구)

  • You, Hoan-Su;Kenrick, Paul;Koh, Yeong-Koo;Yun, Seok-Tai;Kim, Joo-Yong;Kim, Hai-Gyoung;Chung, Chul-Hwan;Ryu, Sang-Ock
    • Journal of the Korean earth science society
    • /
    • v.21 no.6
    • /
    • pp.683-694
    • /
    • 2000
  • Abstrace: The palaeodepositional environment and age of the Cretaceous Hampyeong Basin (southwestern Korea) are reassessed based on new geochemical, lithological, sedimentological, and palaeobotanical data. Results indicate that the Hampyeong Basin was a tectonically active basin comprising predominantly fluvial and lacustrine sediments. Four distinctive facies types have been identified (acidic tuff, black shales/sandstones, red beds, intermediate tuff with tuffaceous conglomerate) and these reflect periods of significant environmental change within the basin and its neighbouring terrains. Volcanism driven by tectonic events provides a source for much of the sediment. The sedimentary sequences compare well with those in the neighbouring Haenam Basin. Sediments of volcanic origin are similar to those of the Neungju Formation of the Yuchon Group. The widespread occurrence of black shales is indicative of extended periods of deposition under anoxic conditions. Measurements of total organic carbon show that the values for the black shales (0.81% to 1.75%) are the average for petroleum source shales. Fossil plants occurred in the black shales and sandstones. The occurrence of platanoid leaves places these sediments in Oishi's angiosperm series, which is consistent with an Aptian/Albian or younger age.

  • PDF

Behavior Analysis of Earth Retaining Walls on the Excavation for Contact Structure (인접 구조물의 터파기로 인한 흙막이 벽체의 거동 분석)

  • Kim, Young-Muk;Jung, Young-Soo;Hong, Chang-Pyo;Shin, Youn-Sub
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2005.03a
    • /
    • pp.1496-1503
    • /
    • 2005
  • The study on the lateral earth pressure is briskly preformed for various conditions such as type of retaining walls, ground condition, and type of supporting systems. It is not simple to determine the distribution of lateral earth pressure accurately, however, because the lateral earth pressure is affected by various factors. This study is performed to analyze the behavior of earth retaining walls for new excavation contacting with existing excavation by comparing with the site measuring values before and after new excavation. On the base of observation, the distribution of strut axial forces is similar to that of ganeral earth retaining walls, but strut axial forces is increased by removal of existing earth anchors. When new excavation is performed contacting with existing excavation, the axial force of strut is decreased because of soil exclusion in the behind walls, but that force is increased after new exeavation. The analysis result show that the installation of strut in middle part makes a effect to not only 1 adjacent strut, but 3-5 adjacent struts. Also during new excavation strut axial forces is decreased by relaxation of total earth retaining wall system.

  • PDF

A Case Study on the Self-Supported Earth Retaining Wall with Different Formations (다양한 형태의 2열 자립식 흙막이 공법 시공사례 연구)

  • Sim, Jae-Uk;Kim, Kyoung-Chul;Son, Sung-Gon;Park, Young-Jin;Im, Jong-Chul
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2010.09a
    • /
    • pp.1039-1049
    • /
    • 2010
  • Excavation support systems are the temporary earth retaining structures that can prevent the lateral movement of soils. The systems are initially performed before other construction operations and have a great impact on the entire construction period. The temporary support system in Korea have been carried out generally along with installing supports, which are struts, tiebacks, and rakers. However, most of existing support systems in application relatively have limitations such as cost increase, construction configuration, and displacement occurred with support systems. Thus, a new retaining support system (referred to as the SSR, New Construction Technology No. 533) was developed to solve the aforementioned problems. This study introduces the design, construction, and maintenance of the SSR system under the different construction conditions. The behavior and characteristics of the SSR system were identified based on the case studies.

  • PDF

Channel Allocation for the Low Earth Orbit Satellite Systems

  • Kim, Soo-Hyun;Kim, Soo-Hyun;Chang, Kun-Nyeong
    • Journal of the Korean Operations Research and Management Science Society
    • /
    • v.22 no.4
    • /
    • pp.37-50
    • /
    • 1997
  • We consider the channel allocation problem for the earth orbit (LEO) satellite systems. This problm is known to be NP-complete and a couple of heuristic algorithms have been developed. In this paper, we convert the problem into a simpler form through the concept of pattern. And we suggest another algorithm based on Simulated Annealing for this simplified problem. The results of performance comparison show that our method works very well. Simulation results are reported.

  • PDF

A Method and System to Compensate Vertical Component of 3-Axes Magnetic Field Sensor Using the Earth's Field (지구자계를 이용한 3축 자계센서의 수직성분 자계 보정방법 및 장치)

  • Jeong Yeong-Yun;Im Dae-Yeong;Yu Yeong-Jae
    • Proceedings of the Korean Institute of Intelligent Systems Conference
    • /
    • 2006.05a
    • /
    • pp.241-244
    • /
    • 2006
  • 본 논문은 지구자계를 이용하여 3축 자계센서의 수직 성분자계를 보정하는 방법과 장치를 제안한다. 자계센서는 설치각도 및 이득오차에 의해 출력 특성이 변화한다. 따라서 자계센서를 사용하기에 앞서 보정이 필요하다. 지구에서 발생되는 지구자계를 이용하여 간편하게 센서의 설치각도 및 이득오차에 의한 영향을 보정하였으며 이를 위한 장치를 설계하였다. 제안한 방법은 실험을 통하여 실용성을 검증하였다.

  • PDF