• Journal of Electrical Engineering and Technology
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• 제12권3호
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• pp.1245-1249
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• 2017

Recently, unusual transformer failures have been reported in 25kV power systems connected with a VCB and transformer. In this study, performance of the protection system, dielectric strength of the transformers, characteristics of switching surges and resonance phenomena were analysed and assessed. All investigations regarding the insulation breakdown of the transformers were carried out by simulations, laboratory tests, factory tests and on-site measurements in order to thoroughly investigate the root causes. Furthermore, experimental methods for investigating the resonance phenomenon were derived and tests were conducted applying the derived method to recreate the phenomenon in the transformer. It is found that resonance between the transformer and switching surge generated by closing a VCB can initiate the breakdown of internal windings of a transformer.

• Journal of the Korean Institute of Landscape Architecture International Edition
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• 제2호
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• pp.9-13
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• 2004

After UNECD(United Nations Conference of Environment and Development) in 1992, ESSD (Environmental Sound and Sustainable Development) is an important concept of urban planning in Korea. The introducing environmental assessment system of urban planning and the district unit planning system were representative cases. In this process, Landchaftplanung(ecological landscape planning) was introduced from Germany. This study was executed for applying ecological landscape planning to Eunpyung New Town in Seoul city, and analyzing the problem to apply this system. The process of ecological landscape planning was followed to (1) the site survey, (2) the analysis and assessment of survey data, (3) the establishing ecological landscape planning. Three master architects participated in all investigations. The major fields of them were landscape architecture, architecture, and urban planning. Master Architects helped many aspects. In conclusion, ecological landscape planning was feasible to be applied to develop other New Town in Korea. However the mediation system is very weak, if different situations are confronted with ecological landscape plan and land use plan in the operative legal framework of Korea. Thus, the legislation of mediation system is necessary for an establishment of ecological landscape planning.

• 한국환경생태학회지
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• 제23권5호
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• pp.418-430
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• 2009

두루미류 취식무리의 미소 취식지 선호에 대한 특성을 밝히기 위하여 철원지역에서 월동기인 2005년 12월에서 2006년 2월, 2007년 1월에서 2월까지 총 12회 실시하였다. 두루미와 재두루미가 먹이로 하는 쌀 낙곡의 밀도는 논의 중앙보다 가장자리에 많았다. 하지만, 두루미류는 논의 중앙보다는 논둑 인근 지역을 취식장소로 이용하는 경우가 많았다. 상대적으로 재두루미는 두루미에 비하여 논의 중앙 지역을 취식장소로 이용하는 비율이 높았다. 두루미의 경우 논둑이 높고 논둑 식생의 높이가 높은 경우와 논둑 높이와 식생의 높이를 합한 높이가 높은 경우를 취식위치로 선호하였다. 재두루미는 논둑, 식생, 논둑과 식생의 높이 합이 키에 비하여 높은 경우를 선호하지 않았다. 또한, 두루미와 재두루미에서 모두 은폐지역에서 취식하는 비율이 날씨요인과 관계가 없었다. 이러한 결과는 두루미류가 개방된 취식지(수평가시권이 넓은 지역)를 선호한다는 기존 가설과는 달리 은폐된 취식지를 선호하는 것으로 나타났다. 또한 종간의 비교에서는 두루미가 재두루미에 비하여 은폐된 지역을 선호하는 것으로 나타났다. 무리크기별 은폐지역과 비은폐지역 취식비율은 두루미와 재두루미 모두 무리크기를 고려하지 않은 취식비율과 차이가 없었다. 결과적으로 두루미가 은폐지역을 선호하고 재두루미가 은폐지역에 상관없이 취식지를 선택하는 경향은 취식무리의 크기에 좌우되지 않는 종 특이적인 성향을 보였다.

• 한국화재소방학회논문지
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• 제30권6호
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• pp.43-47
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• 2016

공판중심주의 강화와 법률시장 개방 등 사법제도의 변화로 인해 화재현장의 해석은 과학적인 증거를 통해 철저한 실체적 진실의 구현을 지향하고 있다. 화재에 대한 실체적 진실 규명의 근거가 되는 물적 증거물에 대한 적정한 수집이 선행되지 않으면 법정에서 증거능력 부정 또는 증명력이 배척되어 조사결과에 대한 신뢰도는 추락하게 된다. 엄정하게 관리된 현장에서 물리적, 화학적으로 변형 우려가 높은 화재 증거물의 특성상 최대한 원형을 보존하도록 채취되어야 하고 채취부터 분석 감정에 이르는 모든 과정이 사진 및 기록으로 유지되어야 하며 이런 과정들에 대한 세부적인 매뉴얼 또는 지침이 규정화 될 필요가 있다. 이런 절차들이 정립되고 조사 기관간 협업 관계가 구축된다면 신뢰도 높은 화재감식 체계가 될 것이다.

• 한국환경농학회:학술대회논문집
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• 한국환경농학회 2009년도 정기총회 및 국제심포지엄
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• pp.220-227
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• 2009

For last about 10 years, the Republic of Korea experienced 3 times of outbreaks of highly pathogenic avian influenza (HPAI) from 10 December 2003 to 30 April 2004 (a total number of 19 outbreaks), 22 November 2006 to 6 March 2007 (a total number of 7 outbreaks), and 1 April 2008 to 12 May 2008 (a total number of 33 outbreaks). Among the totally 59 outbreaks, the infected premises included 35 chicken farms, 17 duck farms, 1 quail farm, and 6 farms rearing mixed species. Control measures were applied according to the HPAI standard operation procedure including depopulation of all infected and suspected flocks, movement restrictions, and disinfection of the infected farms within a 500-meter radius. Including movement restrictions, stringent control measures were additionally applied to two designated zones: the protection zone was an area within a 3-kilometer radius of the outbreak farm, and the surveillance zone was an area between a 3- to 10-kilometer radius of the outbreak farm. Farms with dangerous contacts and/or all of poultry within the protection zone was subjected to preemptive culling. Epidemiological investigations were also carried out including trace-back and trace-forward investigations to identify possible sources of spread and dangerous contact farms. Investigation teams conducted on-site examination of farm premises and facilities, interview with farm owner and staff, and review of records. Genetic and pathogenic characteristics of the virus isolates, and the results of the various surveillance activities were also analyzed. HPAI surveillance conducted in Korea includes passive surveillance of investigating notified cases, and active surveillance of testing high risk groups and areas. HPAI is a notifiable disease in Korea and all suspect cases must be reported to the veterinary authorities. Cases reported for other poultry diseases that require differential diagnosis are also tested for HPAI. Active surveillance includes annual testing of breeder duck farms, broiler duck farms and wild bird surveillance, which is concentrated during the autumn and winter. Surveillance activities conducted prior to the outbreaks have shown no evidence of HPAI infection in Korea.

• 대한토목학회논문집
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• 제31권5B호
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• pp.459-466
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• 2011

본 연구에서는 경상북도 북부지역 5개 지점의 소수력발전 후보지점에 대한 소수력발전 자원조사를 실시하였다. 소수력발전 자원조사는 각각 평 갈수기, 및 홍수기에 유량조사, 수위-유량관계곡선식의 유도, 유량지속곡선의 작성, 발전용량의 산정 및 경제성분석 등으로 구성되었다. 본 연구를 통하여 경상북도 북부지역의 최적 소수력 발전지점 선정을 위한 기초자료를 제시하였으며, 경상북도 예천군 형호리와 경상북도 영주시 문수면 권선리 후보지가 가장 경제성이 높은 것으로 분석되었다. 그러나 소수력발전소 후보지점중 설비용량 500 kW 이하의 경우 개발시 소용량으로 인해 개발효과가 없을 것으로 판단되며, 설비용량 500 kW 이상인 최적 개발 후보지는 경상북도 영양군 입암면 후보지 1개소인 것으로 나타났다.

• 자원환경지질
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• 제32권2호
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• pp.189-201
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• 1999

Paleomagnetic and rock magnetic investigations have been carried out for the Cretaceous Hanyang Group, exposed in the Yongyang Sub-Basins within the Kyeongsang Basin, eastern South Korea. A total of 452 oriented core samples was drilled from 31 sits for the study. The in-situ site mean direction is more dispersed than the mean direction after bedding correction, indicating that the fold test is positive at 95% confidence level. In addition, the stepwise unfolding of the characteristic remanent magfold test is positive at 95% confidence level. In addition, the stepwise unfolding of the characteristic remanent magnetization reveals that a maximum value of k is observed at 90% unfolding. Furthermore, the rock magnetic investigations and electron microscope observations of the representative samples show that the main magnetic carrier of the Hayang Group is the detrital specular hematite of single and pseudo-single domain sizes with negligible contribution of pigmentary hematite grains. These results collectively imply that the ChRM direction is the primary component acquired at the time of the formation of the strata. Provided the primary nature of the ChRM, a magnetostratigraphic correlation between polarities of the studied formation and the Geomagnetic Time Scale indicates that the Hayang Group in the Yongyang Sub-Basin can be correlated to the Cretaceous Long Normal superchron. The paleomagnetic pole position from this study is significantly different from those of the Hayang group in the Euiseong the Milyang sub-Basins. Rather the paleomagnetic pole position of the Hayang Group of the study area is closer to that of the Quaternary period or present time of the Korean Peninsula. It is hypothesized that the study area might be rotated about 25$^{\circ}$ aticlockwise with respect to the Euiseong and Milyang Sub-Basins after the formation of the strata and aquisition of the ChRM, although there is not enough geologic evidence supporting the rotation hypothesis.

• 한국생활과학회지
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• 제20권5호
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• pp.1075-1091
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• 2011

The purposes of this study were to investigate the actual state of indoor air quality in semi-underground multi-family housing units in early summer, to analyze the influencing factors, and to make suggestions for improvement. A series of field investigations were conducted in four target units between June 22, 2010, and June 28, 2010. The field investigations included measurements of indoor air quality as well as the observation of architectural characteristics and living conditions. In addition to the field investigation, on-site questionnaire surveys were administrated to residents in 90 units. The findings are summarized as follows: (1) The average $CO_2$ levels in each of the four units ranged from 759ppm to 1885ppm. $CO_2$ levels in three units exceeded the evaluation standard (1000ppm), and one unit was lower than the standard. This unit had smaller number of staying person and a large amount of ventilation than others; (2) the average CO levels in each unit were almost 0ppm, but 0.1~1.1 levels of CO were revealed at several times; (3) the average PM-10 levels ranged from $8{\mu}g/m^3$ to $40{\mu}g/m^3$, which distributes within the standard ($150{\mu}g/m^3$). The influencing factors of PM-10 levels were analyzed as inflow from outside, the use of a gas range, and the residents' activities; (4) therefore, it was evaluated to be necessary to improve ventilation for the indoor air quality of semi-underground housing in aspect of $CO_2$ levels.

• 한국산학기술학회논문지
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• 제21권12호
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• pp.411-416
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• 2020

산림 현장조사는 현장에서 측정된 데이터를 야장에 수기로 기입하는 방법으로 이루어지고 있으며, 현장 조사 후 결과를 다시 정리해야하는 번거로움이 있다. 이에 본 연구에서는 객체 모델링과 AR을 활용한 방법을 적용하여 시험림에 대한 수목조사에 효율성을 제고하고자 하였다. 3D 레이저 스캐너를 이용하여 연구대상지 1ha 면적의 387개 수목에 대한 데이터를 취득하였으며, 수목 객체의 추출 및 모델링을 통해 수목에 대한 좌표, 수고 및 흉고직경을 산정하였다. 이 방법은 현장에서 데이터 취득에 소요되는 시간을 감소시킬 수 있으며, 디지털화 된 성과물 생성이 가능하기 때문에 관련 시스템 구축을 위한 기초자료로 활용이 가능하다. 또한 수목에 대한 모델링 결과와 GNSS 및 AR 기법을 이용한 조사는 현장에서 조사하는 수목에 대한 좌표와 수고 및 흉고직경 등의 속성정보를 확인할 수 있어 특정 객체의 위치와 속성값을 현장에서 확인하기 어려웠던 기존 조사 방법의 단점을 개선할 수 있었다. 향후 포인트클라우드와 AR 기술을 활용한 방법은 현장조사에 소요되는 인력과 시간을 감소시킬 수 있어 수목조사 및 모니터링의 효율성을 크게 향상시킬 것이다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2000년도 추계학술대회
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• pp.44-63
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• 2000

Situated close to Heathrow Airport, and adjacent to the M4 and M25 Motorways, the site at Axis Park is considered a prime location for business in the UK. In consequnce two of the UK's major property development companies, MEPC and Redrew Homes sought the expertise of Intergeo to remediate the contaminated former industrial site prior to its development. Industrial use of the twenty-six hectare site, started in 1936, when Hawker Aircraft commence aircraft manufacture. In 1963 the Firestone Tyre and Rubber Company purchased part of the site. Ford commenced vehicle production at the site in the mid-1970's and production was continued by Iveco Ford from 1986 to the plant's decommissioning in 1997. Geologically the site is underlain by sand and gravel, deposited in prehistory by the River Thames, with London Clay at around 6m depth. The level of groundwater fluctuates seasonally at around 2.5m depth, moving slowly southwest towards local streams and watercourses. A phased investigation of the site was undertaken, which culminated in the extensive site investigation undertaken by Intergeo in 1998. In total 50 boreholes, 90 probeholes and 60 trial pits were used to investigate the site and around 4000 solid and 1300 liquid samples were tested in the laboratory for chemical substances. The investigations identified total petroleum hydrocarbons in the soil up to 25, 000mg/kg. Diesel oil, with some lubricating oil were the main components. Volatile organic compounds were identified in the groundwater in excess of 10mg/l. Specific substances included trichloromethane, trichloromethane and tetrachloroethene. Both the oil and volatile compounds were widely spread across the site, The specific substances identified could be traced back to industrial processes used at one or other dates in the sites history Slightly elevated levels of toxic metals and polycyclic aromatic hydrocarbons were also identified locally. Prior to remediation of the site and throughout its progress, extensive liaison with the regulatory authorities and the client's professional representatives was required. In addition to meetings, numerous technical documents detailing methods and health and safety issues were required in order to comply with UK environmental and safety legislation. After initially considering a range of options to undertake remediation, the following three main techniques were selected: ex-situ bioremediation of hydrocarbon contaminated soils, skimming of free floating hydrocarbon product from the water surface at wells and excavations and air stripping of volatile organic compounds from groundwater recovered from wells. The achievements were as follows: 1) 350, 000m3 of soil was excavated and 112, 000m3 of sand and gravel was processed to remove gravel and cobble sized particles; 2) 53, 000m3 of hydrocarbon contaminated soil was bioremediated in windrows ; 3) 7000m3 of groundwater was processed by skimming to remove free floating Product; 4) 196, 000m3 of groundwater was Processed by air stripping to remove volatile organic compounds. Only 1000m3 of soil left the site for disposal in licensed waste facilities Given the costs of disposal in the UK, the selected methods represented a considerable cost saving to the Clients. All other soil was engineered back into the ground to a precise geotechnical specification. The following objective levels were achieved across the site 1) By a Risk Based Corrective Action (RBCA) methodology it was demonstrated that soil with less that 1000mg/kg total petroleum hydrocarbons did not pose a hazard to health or water resources and therefore, could remain insitu; 2) Soils destined for the residential areas of the site were remediated to 250mg/kg total petroleum hydrocarbons; in the industrial areas 500mg/kg was proven acceptable. 3) Hydrocarbons in groundwater were remediated to below the Dutch Intervegtion Level of 0.6mg/1; 4) Volatile organic compounds/BTEX group substances were reduced to below the Dutch Intervention Levels; 5) Polycyclic aromatic hydrocarbons and metals were below Inter-departmental Committee for the Redevelopment of Contaminated Land guideline levels for intended enduse. In order to verify the qualify of the work 1500 chemical test results were submitted for the purpose of validation. Quality assurance checks were undertaken by independent consultants and at an independent laboratory selected by Intergeo. Long term monitoring of water quality was undertaken for a period of one year after remediation work had been completed. Both the regulatory authorities and Clients representatives endorsed the quality of remediation now completed at the site. Subsequent to completion of the remediation work Redrew Homes constructed a prestige housing development. The properties at "Belvedere Place" retailed at premium prices. On the MEPC site the Post Office, amongst others, has located a major sorting office for the London area. Exceptionally high standards of remediation, control and documentation were a requirement for the work undertaken here.aken here.