• Title/Summary/Keyword: Field protection

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Field Test on IEC60364-4-44 for the Application in Korean distribution system (IEC60364-4-44의 국내 배전계통 적용을 위한 실증시험)

  • Nam, Kee-Young;Choi, Sang-Bong;Jeong, Seong-Whan;Lee, Jae-Duck;Ryoo, Hee-Suk;Kim, Dae-Kyeong
    • Proceedings of the KIEE Conference
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    • 2006.07a
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    • pp.486-487
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    • 2006
  • The authors have studied on the application of IEC 60364-4-44 to Korean electrical installations of buildings from 2004 sponsored by Korean ministry of commerce, industry and energy and the test field is established in K.E.R.I. (Korea Electrotechnology Research Institute). This paper presents the summary results of establishment of test field and analysis for the application of IEC 60364 in Korea. IEC 60364-4-44 provides rules for the protection against the effects of conducted and radiated disturbances on electrical installations. Especially this standard deals with the protection of low voltage facility against the ground fault in the high voltage side of power distribution system. Many countries define the regulations on the use and production of electrical facilities based on their own power system and technical references which are considered to be suitable for them. The background of circuit of IEC 60364-4-44 is based on the ungrounded system as most of European countries. However, since Korean electric power distribution system is based on multi-grounding system different from European system, it is necessary to evaluate or prove the effect of the IEC 60364-4-44 for introducing and applying it to the domestic grounding system as a Korean standard. This paper presents the establishment of test field to get background data to introduce the IEC 60364-4-44 and to evaluate the standard is applicable to domestic rule for the protection against ground fault through the related test

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Field Investigation of Scour-Protection Methods for Bridges in Small Size Streams of Central Region of Korea (중부 지역 중.소하천 교량의 세굴보호공에 관한 조사연구)

  • Kim, Byoung-Il;Yoon, Ki-Yong;Lee, Seung-Hyun
    • Journal of the Korean Society of Hazard Mitigation
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    • v.5 no.1 s.16
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    • pp.45-53
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    • 2005
  • Scour plays a principal role in maintaining stability and durability of bridges. Especially, in case of severe flood events, flow rate getting increase in a short time, scour can impede the functioning of bridges to the extent that they must be taken out of operation, and even can imperil their stability and structural integrity. In Korea, about 100 bridges were collapsed or damaged every you. Sufficient field investigation, however, was not made and, therefore, no adequate countermeasure for scouring is available. In this study, literature on scour-protection methods are reviewed and data on countermeasures of scouring which were collected through field investigation in central region of Korea are analyzed.

Differences in Field Sign Abundance of Mammal Species Around the Roads in Baekdudaegan Mountains

  • Hur, Wee-Haeng;Lee, Woo-Shin;Choi, Chang-Yong;Park, Young-Su;Lee, Chang-Bae;Rhim, Shin-Jae
    • Journal of Korean Society of Forest Science
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    • v.94 no.2 s.159
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    • pp.112-116
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    • 2005
  • This study was conducted to obtain the information of distribution, protection and management for mammal species in fragmented forest areas around the road from June 2002 to May 2003 in 9 study sites of Baekdugdaegan mountains, Korea. Field signs of twelve mammals, moles Molera robusta, Korean hares Lepus coreanus, Manchurian chipmunk Tamias sibiricus, red squirrels Sciurus vulgaris, Korean racoon dogs Nyctereutes procyonoides, Siberian weasels Mustela sibirica, badgers Meles meles, otters Lutra lutra, Bengal cats Felis bengalensis, wild boars Sus scrofa, water deer Hydropotes inermis and roe deer Capreolus pygargus were recorded in this study. There were no differences in total number of species between 50 m areas and 50-100 m areas from road in snow and non-snow season. Number of mammals' field signs were different in non-snow season between both areas. Red squirrels and Siberian weasels were more abundant in 50 m areas, and Korean hares and Manchurian chipmunks were in 50-100 m areas. Habitat using pattern of mammal species may be affected by the road. Reasonable road construction and maintenance would be needed for protection and management of wildlife and their habitats.

Runoff of Azoxystrobin Applied in Pepper Field-lysimeter (고추 재배 포장 라이시메타를 이용한 Azoxystrobin의 유출 평가)

  • Kim, Chan-Sub;Lee, Hee-Dong;Son, Kyeong-Ae;Gil, Geun-Hwan;Ihm, Yang-Bin
    • The Korean Journal of Pesticide Science
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    • v.20 no.3
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    • pp.228-235
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    • 2016
  • To investigate runoff losses of azoxystrobin from the field by rainfall, the influence of slope degree and length on runoff rate of azoxystrobin from the pepper field were measured. The SC type formulation was applied at the pepper field lysimeter in 2004 and 2005. The azoxystrobin washed down from plant were from 21% to 68% of what the applied. Concentrations of azoxystrobin in the first runoffs were less than $50{\mu}gL^{-1}$. Runoff losses were from 0.26% to 0.59% for 10% slope-plots, from 0.66% to 0.96% for 20% slope-plots, and from 0.84% to 1.78% for 30% slope-plots. Then they decreased with increasing slope-length. Runoff loss of azoxystrobin was closely related to volume of runoff, it was reduced by the ridge and the mulching effect.

Field evaluation of conidia of Beauveria bassiana (Balsamo) Vuillemin strain CS-1 against diamondback moth larvae (포장에서 배추좀나방에 대한 백강균 CS-1의 방제효과)

  • Yoon, Cheol-Sik;Yoon, Tae-Joong;Park, Hyun-Soo;Lee, Sang-Guei;Yoo, Jai-Ki;Lee, Jeang-Oon
    • The Korean Journal of Pesticide Science
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    • v.2 no.2
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    • pp.113-118
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    • 1998
  • The efficacy of conidia of Beauveria bassiana (Balsamo) Vuillemin strain CS-1 that showed high mortality in laboratory and net house was examined against diamondback moth larvae in the field. Conidia ($4{\times}10^{7}$ conidia/ml) were applied to larvae on chinese cabbage in a 1.5% emulsifiable oil-emulsion amended with 4% clay at a volume of 0.55 L/3.3 $m^{2}$. There were no significant differences among plants and replicates in the deposition of spray droplets on water-sensitive papers or of conidia on leaves and larvae. Weather conditions were rainy and cool during first few days, and then hot and dry. Persistence of conidia was equally short on both leaves and larvae. Nevertheless, treatment of B. bassiana potentially reduced larval populations. But the field efficacy was lower than the laboratory efficacy. This reduced efficacy was ascribed to unfavorable environmental conditions.

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Development and Performance Evaluation of the Expanded Metal Rockfall Protection Fence

  • Hwang, Young-Cheol;Kim, Bum-Joo;Noh, Heung-Jae
    • Journal of the Korean GEO-environmental Society
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    • v.6 no.3
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    • pp.35-45
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    • 2005
  • The rockfall protection fence is one of the most common rockfall protection methods in Korea. The typical rockfall protection fence consists mainly of three parts ; H-beam supports, wire meshes, and wire ropes. The design of the rockfall protection fence is made such that the total energy absorbing capacity of the fence. Therefore, resulting from the combined energy absorbing capacity of the three parts is larger than the falling energy of rocks. In present study, a new rockfall protection fence, constructed using expanded metals instead of the existing wire rope and wire mesh for the typical type of rockfall protection fence, was evaluated on its performance by conducting both laboratory and field tests. Also, for a comparison, the same tests were performed on the typical rockfall protection fence. The test results revealed that the expanded material is an economic alternative to the existing protection materials and the expanded metal rockfall protection fence exhibits the higher energy absorbing capacity compared to that of the typical rockfall protection fence.

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Development and Evaluation of Loop-Mediated Isothermal Amplification Assay for Rapid Detection of Tylenchulus semipenetrans Using DNA Extracted from Soil

  • Song, Zhi-Qiang;Cheng, Ju-E;Cheng, Fei-Xue;Zhang, De-Yong;Liu, Yong
    • The Plant Pathology Journal
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    • v.33 no.2
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    • pp.184-192
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    • 2017
  • Tylenchulus semipenetrans is an important and widespread plant-parasitic nematode of citrus worldwide and can cause citrus slow decline disease leading to significant reduction in tree growth and yield. Rapid and accurate detection of T. semipenetrans in soil is important for the disease forecasting and management. In this study, a loop-mediated isothermal amplification (LAMP) assay was developed to detect T. semipenetrans using DNA extracted from soil. A set of five primers was designed from the internal transcribed spacer region (ITS1) of rDNA, and was highly specific to T. semipenetrans. The LAMP reaction was performed at $63^{\circ}C$ for 60 min. The LAMP product was visualized directly in one reaction tube by adding SYBR Green I. The detection limit of the LAMP assay was $10^{-2}J2/0.5g$ of soil, which was 10 times more sensitive than conventional PCR ($10^{-1}J2/0.5g$ of soil). Examination of 24 field soil samples revealed that the LAMP assay was applicable to a range of soils infested naturally with T. semipenetrans, and the total assay time was less than 2.5 h. These results indicated that the developed LAMP assay is a simple, rapid, sensitive, specific and accurate technique for detection of T. semipenetrans in field soil, and contributes to the effective management of citrus slow decline disease.

Performance Assessment Model for Fire Safety Protection of Office Building (사무소 건축물의 화재안전 성능 평가모델)

  • Yang, Eun-Bum;Hwang, Young-Sam;Lee, Chan-Sik
    • Journal of the Korean Society of Safety
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    • v.19 no.2
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    • pp.69-74
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    • 2004
  • This study is to suggest a performance assessment model for fire safety protection of office building 34 asessment elements were chosen by interviewing with experts, reviewing several codes and existing relevant models, assessment elements included in this model are comprised of five categories which are 'performace of protected area', 'performance of fire partition', 'safety performance of fire escape', 'performace of smoke control system' and 'performace of fire fighting equipment'. The weight of each element was computed by systematic approach like an AHP (analytical hierarchy process), which was conducted by experts who work in the field of fire protection. This model would be utilized as a part of assessment model for the overall performace of domestic office building.

The Construction of distribution test facilities of lightning protection equipment (배전급 내뢰설비 시설효과 분석 실증시험설비 구축에 관한 연구)

  • Kang, Moon-Ho
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2004.11a
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    • pp.301-303
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    • 2004
  • In distribution system about 5% of total outage is due to the lightning stroke. In order to reduce the rate of outage occurrence, distribution lightning protection equipments such as a secondary arrester, arching horn and various ground electrodes are developed and installed in the inside and outside of the county. Therefore it is needed to construct the test facilities to analyze the effect of these equipments. In this paper we describe the main content of the test facilities of lightning protection equipments. We have completed the field test of distribution lightning protection equipments for example lightning arrester, secondary arrester and arching horn etc.

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The consumer policies for the electronic transaction (선진국의 전자거래 소비자정책)

  • Park, Ho-Yong
    • International Commerce and Information Review
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    • v.4 no.2
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    • pp.57-76
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    • 2002
  • This paper surveys consumer policies for the internet transaction in the developed countries. Recently the internet transaction has been witnessing a remarkable change represented by the rapid spread of "revolution of distribution". It cannot be, however, stated that internet transaction will dominates all the market places without enhancing consumer's reliability in the internet transaction. Many countries made an efforts to the consumer protection in order to develop infra-structure of information industry. We will soon discover a new paradigm that consumer protection is not a tool for development of cyber market but the goal itself. We survey the process of consumer policies discussed in the developed countries and study the point of prevailing arguments of the consumer protection in the internet transaction. The arguments discussed in OECD meetings are debatable, especially, to the degree of government intervention in the field of consumer protection between EU and US. In contrast of US insisted on the minimum intervention of the government, EU suggest the opinion of more aggressive role of government in consumer policy in the cyber market. This paper attempts to provide several guide lines of Korean consumer policy in the cyber market.

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