• 한국지하수토양환경학회지:지하수토양환경
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• 제22권5호
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• pp.13-22
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• 2017

Accurate assessment of agricultural groundwater usage is an essential task to cope with drought that occurs irregularly in time and location. In this study, the agricultural groundwater usage was calculated in nationwide public wells (1,386 bedrock wells) during 5-year period (2010-2014) by using electric power consumption and well specification data. National average of agricultural groundwater usage per each well was estimated as $66.2m^3/day$, corresponding to 21.6% of total permitted volume of groundwater in each well. Chungcheong Nam-do had the highest usage with 38-55.6%. The value increased to 58.1% when the total permitted volume was based upon the supply standard against drought, and the value reached 100% in Chungcheong Nam-do. In Ganghwa distirct that suffered from severe drought in recent years, the average groundwater usage was 61.4%. In 2014, when the drought was the most severe with 45% precipitation of the average annual rainfall, the nationwide usage was turned out to be 25.6%, indicating about 4% higher than average agricultural groundwater usage 21.6%. Therefore, the quantitative assessment of groundwater usage in this study signifies that adequate use of groundwater is crucial to cope with agricultural drought.

• 지질공학
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• 제27권4호
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• pp.383-392
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• 2017

하천 인근에서 농경지 경작 및 생공용수 등의 이용을 위한 과도한 지하수의 취수는 하천수량 감소의 주요 원인으로 인식되고 있다. 따라서 수자원 관리에 있어서 하천 인근 지하수 관리는 매우 중요하며, 이를 위해서는 하천 인근 지하수 정보 파악이 우선되어야 한다. 본 연구에서는 하천으로부터의 이격거리에 따른 지하수 관정의 비율과 하천 인근에 포함된 관정의 분포 특성을 파악하기 위해 안성천 유역을 대상으로 지하수 취수계획량 현황을 조사하였다. 안성천 수계 전체 관정 중 하천 인근에 포함된 허가관정의 취수계획량 비율은 20.6%, 하천 인근에 포함된 신고관정의 경우는 31.3%로 나타났다. 하지만 하천 인근 관정의 전체 취수계획량 중 허가관정은 11.4%, 신고관정은 88.6%에 해당하는 것으로 나타나 하천인근에서 신고관정의 취수비율이 월등히 높은 것으로 분석되었다. 현재까지는 지하수법에 의해 하천 인근 지하수 개발시 단지 허가관정에 대해서만 의무적으로 지하수영향조사서를 작성하도록 되어있으나 하천 인근의 이용관정 중 신고관정의 양이 훨씬 많은 것을 감안하면 신고관정에 대한 적극적이면서도 신중한 관리가 필요할 것으로 판단된다.

• Steel and Composite Structures
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• 제35권2호
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• pp.261-278
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• 2020

In steel-concrete composite beams, to improve the cracking resistance of the concrete slab in the hogging moment region, a new type of connector in the interface, named uplift-restricted and slip-permitted screw-type (URSP-S) connector has been proposed. This paper focuses on the behavior of steel-concrete composite beams with URSP-S connectors. A total of three beam specimens including a simply supported beam with URSP-S connectors and two continuous composite beams with different connectors arrangements were designed and tested. More specifically, one continuous composite beam was equipped with URSP-S connectors in negative moment region and traditional shear studs in other regions. For comparison, the other one was designed with only traditional shear studs. The failure modes, crack evolution process, ultimate capacities, strain responses at different locations as well as the interface slip of the three tested specimens were measured and evaluated in-depth. Based on the experimental study, the research findings indicate that the larger slip deformation is allowed while using URSP-S connectors. Meanwhile, the tensile stress reduces and the cracking resistance of the concrete slab improves accordingly. In addition, the overall stiffness and strength of the composite beam become slightly lower than those of the composite beam using traditional shear studs. Moreover, the arrangement suggestion of URSP-S connectors in the composite beam is discussed in this paper for its practical design and application.

• Journal of Chest Surgery
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• 제19권2호
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• pp.358-362
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• 1986

Esophageal atresia and tracheoesophageal fistula may occur as separate entities but usually occur in combination. Recently we were experienced a case of esophageal atresia with distal tracheoesophageal fistula in infant patient who presented the symptoms of projectile vomiting and dyspnea. The diagnosis was made by the esophagography and the Haight`s operation was performed transpleurally through 4th intercostal space after gastrostomy. Operative patient tolerated all the operative procedures well in spite of postoperative respiratory complication and recovered uneventfully, permitted feeding on 10th postoperative day. On follow up study after 5th months, Patient reveals good health without other problem.

• International Journal of Naval Architecture and Ocean Engineering
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• 제5권3호
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• pp.325-332
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• 2013

Diffuse interface model for numerical analysis was used to compute supercavitating flows around various cavitators. The ambient pressures of 2 atm permitted cavitation studies in a range of cavitation number, ${\sigma}=0.1$ to 1.0 on selected conical and disk-headed cavitors. The computed results were compared with relation by Reichardt. Drag coefficient obtained from pressure forces acting on the cavitator also compared well with those obtained from analytical relations.

• 유기물자원화
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• 제24권4호
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• pp.21-29
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• 2016

서울시 25개 자치구가 운영하는 생활폐기물 적환시설을 대상으로 시설의 기능, 지역 친화성, 규범 순응성 등의 3개 영역에 대해 현황을 분석하고 개선방안을 모색하였다. 65개 적환장 중 46개소는 매일 반출이 필요한 대량폐기물을, 19개소는 3~30일 범위에서 체류 후 반출되는 소량폐기물을 다루었다. 57%의 시설이 주거지역과 상업지역에 설치되어 있었다. 또한 57%의 적환장은 나대지 위에 장비만 두고서 적환작업을 하였다. 79%의 적환장은 재활용선별장 같은 시설과 근접하지 않고 독립적으로 존재했다. 도시계획법의 의한 환경기초시설로 지정된 경우는 17%에 불과했고, 폐기물관리법의 규정대로 허가받은 수집 운반업자가 운영하는 적환장은 31% 수준이었다. 적환장은 그 역할에서 시설 최적화, 자원화 확대 같은 정부의 폐기물관리 정책과 부합하였으나 주거지역이나 상업지역 같은 도심에 입지하기에는 환경대책이 미흡하고 규범과 불일치하는 면이 있었다. 앞으로 적환장이 도심의 환경기초시설로 자리매김하려면 건물 밀폐화, 기능의 종합화 등의 과제를 풀어야 한다.

• Steel and Composite Structures
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• 제36권1호
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• pp.1-16
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• 2020

In steel-concrete composite beams, to improve the cracking resistance of the concrete slab in the hogging moment region, a new type of connector in the interface, named uplift-restricted and slip-permitted screw-type (URSP-S) connector has been proposed. This paper focuses on the behavior of steel-concrete composite beams with URSP-S connectors. A total of three beam specimens including a simply supported beam with URSP-S connectors and two continuous composite beams with different connectors arrangements were designed and tested. More specifically, one continuous composite beam was equipped with URSP-S connectors in negative moment region and traditional shear studs in other regions. For comparison, the other one was designed with only traditional shear studs. The failure modes, crack evolution process, ultimate capacities, strain responses at different locations as well as the interface slip of the three tested specimens were measured and evaluated in-depth. Based on the experimental study, the research findings indicate that the larger slip deformation is allowed while using URSP-S connectors. Meanwhile, the tensile stress reduces and the cracking resistance of the concrete slab improves accordingly. In addition, the overall stiffness and strength of the composite beam become slightly lower than those of the composite beam using traditional shear studs. Moreover, the arrangement suggestion of URSP-S connectors in the composite beam is discussed in this paper for its practical design and application.

• Biotechnology and Bioprocess Engineering:BBE
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• 제8권6호
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• pp.331-337
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• 2003

Unicellular green algae of the genus Dunaliella thrive in extreme environmental conditions such as high salinity, low pH, high irradiance and subzero temperatures. Species of Dunaliella are well known in the alga biotechnological industry and are employed widely for the production of valuable biochemicals, such as carotenoids. Some strains of Dunaliella are cultivated commercially in large outdoor ponds and are harvested to produce dry algal meals, such as polyunsaturated fatty acids and oils for the health food industry, and coloring agents for the food and cosmetic industries. During the past decade, the advances in molecular biology and biochemistry of microalgae, along with the advances in biotechnology of microalgal mass cultivation, enabled this microalga to become a staple of commercial exploitation. In particular, the advent of molecular biology and mutagenesis in Dunaliella has permitted enhancements in the carotenoids content of this green alga, making it more attractive for biotechnological applications. Accordingly, the present review summarizes the recent developments and advances in biotechnology of carotenoid production in Dunaliella.

• 한국통신학회논문지
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• 제36권2B호
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• pp.141-147
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• 2011

본 연구에서는 국내 FM 방송 가용주파수 확보 가능성을 확인하기 위하여 600kHz 채널이격 간격에 대한 동일 송신소 이격실험을 실시하였다. 통일 송신소에서 주파수를 600kHz로 이격할 경우, 수신기를 통한 주관적 음질평가, 전계강도 등의 특성이 비교적 양호한 것으로 평가되어 사전 시뮬레이션 및 충분한 Field Test 등의 사전 분석을 통해 사용할 수 있음을 확인하였다.

• Journal of Chest Surgery
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• 제20권3호
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• pp.565-569
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• 1987

The first description of the pathologic anatomy of esophageal atresia was presented by Duration in 1670, it was not successfully treated until 1939 when the first two survivors of staged correction were described by Ladd and Levin. In 1941 Haight and Towsley performed the first successful primary repair. Recently we were experienced a case of esophageal atresia with tracheoesophageal fistula an infant patient who presented the symptoms of vomiting and dyspnea. The diagnosis was made by the esophagography with Diagnosis. The operation was performed extrapleurally through 4th intercostal space after gastrostomy. The fistula was closed by triple ligation and the upper pouch was then brought into apposition with the presenting surface of the lower esophageal segment and an end to side anastomosis was fashioned with a single layer of sutures. Operative patient tolerated all the operative procedure well in spite of postoperative respiratory complication and recovered uneventfully, permitted feeding on 9th postoperative day after esophagography.