• Title/Summary/Keyword: Earth systems

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Investigation for Earth Resistance and Leakage Current of D/L (배전선로 접지저항 및 누설전류 실태조사)

  • Lee, H.G.;Ha, T.H.;Bae, J.H.;Ha, Y.C.;Kim, D.K.
    • Proceedings of the KIEE Conference
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    • 2003.11a
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    • pp.379-381
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    • 2003

  • The sharing of common corridors by electric power transmission lines and pipelines is becoming more common place. However, such corridor sharing can result in undesired coupling of electromagnetic energy from the power lines to the near facilities. This causes induced voltages on underground metallic pipelines due to the power line currents. This could cause AC corrosion in the pipeline, which could in turn lead to disastrous accidents, such as gas explosion or oil leakage. This paper investigates for the limitation of induced voltage on the buried metal structures which is used in the inside and outside of the country. And then we measure the earth resistance and leakage current of 22.9kV distribution lines and pipe to soil potential of near pipelines in Seoul Korea. Hereby we can see the leakage current flowing through the earthing electrode have an effect on near pipelines.

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Microbial population dynamics in constructed wetlands: Review of recent advancements for wastewater treatment

  • Rajan, Rajitha J.;Sudarsan, J.S.;Nithiyanantham, S.
    • Environmental Engineering Research
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    • v.24 no.2
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    • pp.181-190
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    • 2019

  • Constructed wetlands are improvised man-made systems, designed for adopting the principle of natural wetlands for purifying wastewater - the elixir of life. They are used widely as a cost-effective and energy-efficient solution for treating greywater generated from different tertiary treatment sources. It provides an elaborate platform for research activities in an attempt to recycle earth's natural resources. Among the several organic impurities removal mechanisms existing in constructed wetland systems, the earth's active microbial population plays a vital role. This review deals with the recent advancements in constructed wetland systems from a microbiological perspective to (effect/ devise/ formulate) chemical and physical treatment for water impurities. It focuses on microbial diversity studies in constructed wetlands, influence of wetland media on microbial diversity and wetland performance, role of specific microbes in water reuse, removal of trace elements, some heavy metals and antibiotics in constructed wetlands. The impurities removal processes in constructed wetlands is achieved by combined interactive systems such as selected plant species, nature of substrate used for microbial diversity and several biogeochemical effected reaction cycles in wetland systems. Therefore, the correlation studies that have been conducted by earlier researchers in microbial diversity in wetlands are addressed herewith.

  • https://doi.org/10.4491/eer.2018.127 인용 PDF KSCI

Introduction of the Global Geodetic Observing System (지구측지관측시스템(GGOS) 연구동향)

  • Shin, Young-Hong;Park, Jong-Uk;Seo, Ki-Weon
    • Journal of the Korean earth science society
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    • v.30 no.3
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    • pp.381-397
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    • 2009

  • The Modem Geodesy monitors physical and geometrical shape and motion of the Earth and, more importantly, its temporal variations with unprecedented precision. It provides accurate and stable reference frames for Earth observations in the Space era. Furthermore, with an aid of interdisciplinary approaches, it also traces the causes of the variations in shape and motion of the Earth and eventually contributes to a better understanding of the Earth system. The International Association of Geodesy (IAG) has established the Global Geodetic Observing System (GGOS) to integrate the multitude of geodetic tools and tried to contribute to the management of global environmental changes as a partner of the Global Earth Observation System of Systems (GEOSS). Here we introduce the contribution of geodesy to the various fields of Earth Science by focusing on GGOS and encourage interdisciplinary researches.

  • https://doi.org/10.5467/JKESS.2009.30.3.381 인용 PDF KSCI