• 지구물리와물리탐사
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• 제14권2호
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• pp.158-163
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• 2011

소형루프 전자탐사는 폐기물 매립지로부터 발생되는 오염원의 범위 및 경로를 추적하기 위한 개략적인 조사에 효과적인 방법이다. 본 연구에서는 매립물 분포 범위 및 침출수 발생 범위 파악을 위하여 다중주파수를 이용한 소형루프 전자탐사를 수행하였으며, 탐사 결과를 24곳의 트렌치 조사와 12개소의 시추조사에서 확인된 오염범위와 비교한 결과 매립지의 규모 및 침출수 범위 추정이 가능한 것으로 밝혀졌다. 그러나 본 매립지가 해안지역 삼각주에 위치함에 따라 약10 m 이하 심도에서 나타나는 10 ohm-m 이하의 낮은 전기비저항의 원인을 규명하기 위해서는, 10 m 이하 심도까지 시추조사를 병행하는 것이 바람직할 것으로 판단된다.

• 토지주택연구
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• 제2권4호
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• pp.397-406
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• 2011

본 연구는 지속 가능한 주거환경을 구현하기 위한 실천전략의 하나로서 100년의 내구성과 가변성을 갖는 장수명 공동주택 표준모델에 실질적으로 적용할 수 있는 다양한 가변요소 시스템 개발을 주된 목적으로 한다. 연구방법으로는 장수명 공동주택 표준모델을 적용한 '실험주택'을 대상으로 개발한 각종 가변요소 시스템과 기술들을 통합하고 단계별 현장 적용성 평가, 전문가 의견조사 및 설문조사 등을 실시하였다. 본 연구는 총 3단계로 구분하여 수행하였다. 1단계에서는 고정요소인 전체 구조체와 가변요소인 건식외벽, 창호 등을 시공함과 동시에, 전용면적 $84m^2$에 가변요소 시스템을 시공하면서 현장 적용성을 평가하였다. 2단계에서는 전용면적 $50m^2$ 3세대를 대상으로 국내 최초로 수직통합형 세대(전용$50m^2$+전용$40m^2$)와 수평확장형 세대(전용$50m^2$+전용$10m^2$)를 대상으로 다양한 가변요소시스템의 현장 적용성 평가를 실시하였다. 3단계에서는 본 연구에서 개발한 건식 온돌의 현장검증을 위한 각종 성능평가 실험과 기 사용한 주택부품의 해체, 이동 및 재시공을 통한 3R 구현 정도 파악 등 실용성 제고를 위한 다양한 검증 작업도 함께 실시하였다.

• 환경영향평가
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• 제10권3호
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• pp.223-234
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• 2001

In this study, we conducted a survey to examine the runoff characteristics of nonpoint sources, which wash off pollutants from the surface of basin during rainfall and affect water pollution of streams. An Anyangchun basin in the region Ewiwang City was selected as a study site. The basin divided into several subbasins such as Wanggokchun, Ojeonchun, and Anyangchun based on the tributaries, which confluence to the main stream of Anyangchun. Four times of field examination had been carried out between July and August of 2000, and water quality data collected from the surveys had been analysed. The survey includes in-situ flow, DO and PH measurements in the outlet of catchment. Laboratory analysis includes BOD, TN, TP. From the result, pollutant by runoff of nonpoint sources were washed out along with stormwater in the beginning of rainfall, and flowed into streams resulted in stream pollution. In case of BOD, the load from Ojeonchun catchment, most of which included urban areas, took up 50% of the total load from the entire watershed. Thus, by the results, it is clear that runoff load by urban nonpoint sources plays an important role in the control and management of nonpoint sources for the watershed.

• 방사성폐기물학회지
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• 제21권4호
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• pp.543-558
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• 2023

Currently, Japan is undertaking a nationwide project to measure and map radioactive contamination around Fukushima, as part of the efforts to restore normalcy following the nuclear accident. The Japan Atomic Energy Agency (JAEA) manages the Fukushima Environmental Safety Center, located approximately 20 km north of the Fukushima Daiichi nuclear power plant in Minamisōma City, Fukushima Prefecture. In collaboration with the JAEA, this study involved conducting comparison experiments and analyses with radiation detectors in high radiation environments, a challenging task in Korean environments. Environmental radiation surveys were conducted using three types of detectors: CZT, NaI(Tl), and LaBr₃(Ce), across two contaminated areas. Dose rate values were converted using dose rate conversion factors for each detector type, and dose rate maps were subsequently created and compared. The detectors yielded similar results, demonstrating their feasibility and reliability in high radiation environments. The findings of this study are expected to be a crucial reference for enhancing the verification and supplementation of procedures and methods in future radiation measurements and mobile surveys in high-radiation environments, using these three types of radiation instruments.

• 한국수산과학회지
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• 제47권6호
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• pp.1055-1062
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• 2014

Hydroacoustic surveys were conducted for spatio-temporal distribution and size estimation of fish in the Yongdam reservoir, Korea, from April to July 2014. Acoustic data were collected along acoustic transects using a 120 kHz scientific echosounder. The received acoustic data were the in situ acoustic target strength (dB) and nautical area scattering coefficient ($m^2/mile^2$). Data on fish behavioral patterns and size were collected using a DIDSON acoustic camera at stationary stations. Fish were mainly distributed in the center channel and close to the outer Yongdam reservoir. Acoustic density of fish in the summer season were higher than in the spring season. The seasonal vertical distribution pattern of fish aggregations may be strongly related to the vertical temperature structure. The size distribution of fish obtained from an acoustic camera correlated well with the acoustic size of fish from an echosounder.

• Ocean and Polar Research
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• 제30권2호
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• pp.181-191
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• 2008

This study aims at assessment of spatio-temporal distribution of demersal fish aggregations near the west coast of Jeju Island using hydroacoustic survey. A 200 kHz split beam transducer attached to a small towed body was used for all acoustic investigations. The received acoustic data were in situ acoustic target strength (TS, dB) for all pings and nautical area scattering coefficient(NASC, $m^2/mile^2$) for 0.1 mile along 12 acoustic transects. Demersal fish aggregations are distributed around the coastal slope having 20 to 30 m depth throughout all seasons. The concentration is higher during the summer season. With regard spatial distribution, higher demersal fish aggregations have been detected near the West coast of Shinchang and especially near Chagwi-do. Pelagic fish aggregations were higher to the south of Chagwi-do during the spring season. Additionally, standing stock of demersal fish aggregations from the NASC data, TS function, and length-weight function of dominant species was estimated as follows: 3.2 ton (CV 21.8%) in December 2006, 17.9 ton (CV 21.6%) in April 2007, 30.8 ton (CV 17.8%) in June 2007, and 22.5 ton (CV 24.2%) in October 2007. The application of hydroacoustic methods offers a new approach to understanding spatiotemporal structure and estimate the biomass of demersal fish aggregations in the coastal area. And the results can be made up limitations of qualitative analysis through net and diving for fisheries resources survey in coastal area.

• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2007년도 공동학술대회 논문집
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• pp.307-312
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• 2007

Seawater intrusion in estuarine regions is an important issue in protecting groundwater against salinity increase as well as in protecting construction materials against corrosion. For example, drain water ejected during accelerated consolidation for the improvement of soft ground can cause damages to farm land because the drain water from seawater intrusion zones contains salinity. In this study, we have employed correlation analysis between resistivity value and salinity of in situ pore water. The correlation analysis indicates that resistivity and salinity are in exponential relationship with good correlation. Therefore we suggest that rapid estimation of spatial distribution of NaCl is possible using resistivity data.

• 천문학회보
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• 제44권1호
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• pp.68.4-68.4
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• 2019

It is inferred that many stars in the Galactic halo or bulge were once members of globular clusters (GCs), which are now dissolved. To distinguish the GC-originated stars, which can provide valuable information on the origin of the bulge and halo, from the in situ field stars, the Na abundance plays an important role. However, the interstellar Na in certain directions can unnecessarily enhance the estimate of the Na abundance from stellar spectra due to blended Na D lines unless the spectral resolution is very high, which allows to resolve the lines from the interstellar Na. In this study, we present a means of correcting the Na abundance affected by the interstellar Na in the low-resolution of the Sloan Digital Sky Survey stellar spectra.

• 한국표면공학회지
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• 제37권3호
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• pp.137-145
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• 2004

This study surveys the microscopic wear of CVD TiN coatings in repeated sliding, using the SEM Tribosystem as in-situ system. According to the research, the depth of wear groove and the specific wear amount are changed by the transition of the microscopic wear mode. This investigation leads to the fact that the change of wear characteristics produces the transition of the wear mode. In this survey, four modes are observed for CVD TiN coatings with the thickness of 1.6$\mu\textrm{m}$: ploughing, powder formation, flake formation and coating delimitation. The microscopic wear properties is quantitatively evaluated in terms with the microscopic wear mode and the specific wear amount. These relationships prove that the observation of wear modes with a SEM Tribosystem is useful to evaluate wear properties.

• 한국지반공학회논문집
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• 제36권9호
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• pp.5-20
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• 2020

2017년 발생한 포항지진에서는 계기지진 이래 처음으로 액상화 현상이 목격되었다. 본 연구에서는 액상화 현상이 목격된 포항시 (1) 송림공원, (2) 흥해읍 망천리, (3) 흥안리를 대상으로 다양한 지반조사 및 실내실험을 수행하였다. 액상화 발생위치의 동적특성을 파악하기 위해 지반조사 항목으로는 표준관입시험(SPT), 콘관입시험(CPT), 표면파탐사(MASW), 밀도검층, 다운홀테스트, 전기비저항탐사를 수행하였고, 현장에서 채취한 시료를 바탕으로 진동삼축압축 시험기를 통해 액상화실험을 수행하였다. 그 결과 세 곳 모두 지하수위가 높고 얕은 심도에 연약한 모래층이 존재하며, 송림공원에서 채취한 모래는 주문진 표준사, Toyoura 모래, Ottawa 모래에 비해 액상화 저항강도가 작은 것을 확인하였다.