• 한국농공학회지
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• 제24권2호
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• pp.49-55
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• 1982

The purpose of this study is to classify the factors influenced on the damages of head works suffered from the storm flood occurred on July 22 1980 in both Musim and Bochong rivers and to find out an integral counter measures against the causes influenced on the disaster of head works in the engineering aspect of planning, design, construction and maintenance. In this survey, number of samples was taken 25 head Works, and the counter measures against the causes of their disasters summarized was as follows, 1. In the aspect of planning a. As the flood water level after the establishment of head works is more increased than the level before setting of head works owing to having more gentle slope of river bed between the head works than nature slope of river bed. Number of head works should be reduced for the appropriate annexation of them b. In the place where head works is established on the curved point of levee, the destruction of levee becomes severe by the strong deflective current. Therefore the setting of head works on the curved point should be kept off as long as possible and in case of unavoidable circumstances the construction method such as reinforced concrete wall or stone wall filed with concrete and anchored bank revetments should be considered. 2. In the aspect of design a. As scoring phenomena at up stream is serious around the weir Where the concentration of strong current is present in such a place, up stream apron having impermeability should be designed to resist and prevent scoring. b. As the length of apron and protected bed is too short to prevent scoring as down stream bed, the design length should be taken somewhat more than the calculated value, but in the case the calculated length becomes too long to be profitable, a device of water cushion should be considered. c. The structure of protected river bed should be improved to make stone mesh bags fixed to apron and to have vinyl mattress laid on river bed together with the improvement for increasing the stability of stone mesh bags and preventing the sucked sand from the river bed. d. As the shortage of cut-off length, especialy in case of the cutoffs conneting both shore sides of river makes the cause of destruction of embankment and weir body, the culculation of cut-off length should be taken enough length based on seepage length. 3. In the aspect of design and constructions a. The overturing destruction of weir by piping action was based on the jet water through cracks at the construction and expansion joints. therefore the expansion joint should be designed and constructed with the insertion of water proof plate and asphalt filling, and the construction joint, with concaved shape structure and steel reinforcement. b. As the wrong design and construction of the weep holes on apron will cause water piping and weir destruction, the design and construction of filter based on the rule of filter should be kept for weep holes. c. The wrong design and construction of bank revetment caused the severe destruction of levee and weir body resulting from scoring and impulse by strong current and formation of water route behind the revetment. Therefore bank revetment should be designod and constructed with stone wall filled with concrete and anchored, or reinforced concrete wall to prevent the formation of water flow route behind the wall and to resist against the scoring and impulse of strong stream. 4. In the aspect of maintenance When the damaged parts occurred at head works the authorities and farmers concerned should find and mend them as soon as possible with mutual cooperation, and on the other hand public citizen should be guided for good use of public property.

• 한국환경보건학회지
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• 제32권5호
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• pp.469-477
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• 2006

When denitrification was connected with a single stream process by using biofilter and sulfur-limestone, it was found that such connection enabled highly efficient nitrification without special unit operation of microorganisms or injection of external carbon sources which is being shown in general biological treatment processes. It was observed that in the trickling filter bed, decomposition of organic substances and highly efficient nitrification by both the forced pressure feed trickling and the air fan were simultaneously done. In the denitrification tank where sulfur-limestone was mixed at a certain ratio, limestone was used by autotrophic microorganisms as a source of supply for alkalinity, and nitrate $NO_{3}^{-}$-N was denitrified into nitrogen gas. And in the sulfur-limestone autotrophic denitrification, $NO_{3}^{-}-N\;or\;NO_{2}^{-}-N$ was denitrified as a sulfur compound in reduction state was oxidized into a final output of $SO_{4}^{-2}$. The mean concentration of the discharge water was 8.6 mg/l for T-N and 0.8 mg/l for T-P, respectively, and their mean treatment efficiency was 79.2% and 80.8%, respectively. Implementing highly efficient denitrification without injection of an external organic carbon source or internal return, it is concluded that the proposed process is suitable for a sewerage in a small village with the merits of low power consumption and easy maintenance.

• 환경생물
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• 제36권2호
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• pp.174-179
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• 2018

Clithon retropictus has been protected by the Ministry of Environment as an endangered species since 1998 and has been listed on the state red list of endangered species category II. It is viewed as a representative for all endangered species in the northeastern coastal waters of Korea. Most of the habitats of C. retropictus have been found to be in an unstable state because of development projects such as road construction, small stream development, irrigation for securing agricultural water, and flood prevention. These habitats are damaged by small stream maintenance projects and development, and the risk of damage is increasing and active efforts are needed in order to protect them. Although the Ministry of Environment is striving to preserve this endangered species, the habitat of C. retropictus is still facing external threats because it spreads to only a small area at high densities. Therefore, in order to protect the habitat of C. retropictus, a level II endangered species, it is urgent to make an effort to minimize habitat damage and to take measures for its protection.

• 한국습지학회지
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• 제18권4호
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• pp.448-455
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• 2016

환경부는 비점오염원 관리를 위해 시범사업으로 12개의 비점오염 저감시설을 경안천 유역에 설치하였으며, 2006년부터 모니터링이 시작되었다. 본 연구는 비점오염 저감시설의 오염부하량, 저감효율, 유지관리 활동 등의 장기간 수행된 모니터링 결과를 바탕으로 각 시설의 경제성을 평가하기 위해 수행되었으며, 생애주기비용(Lifecycle cost, LCC)을 분석하였다. 비점오염 저감시설의 유지관리는 시설경관을 향상시키기 위한 심미적 관리가 중점적으로 수행된 것으로 나타났으며, 저류형 시설(Retention Pond, RP)이 년간 8,483$, 침투형 시설(Infiltration System, IS)이 8,888$로 대부분 비슷한 비용이 발생한 것으로 분석되었다. LCC는 인공습지(Constructed Wetland, CW)가 가장 높은 것($418,324)으로 나타났으며, 반면에 식생형 시설(Vegetated System, VS)이 가장 낮은 것($210,418)으로 분석되었다. 본 연구에서 조사된 비점오염 저감시설의 LCC와 하수처리장 등 수질처리시설의 LCC를 비교한 결과 비점오염 저감시설이 낮은 것으로 나타났다. 한편, 처리용량 대비 생애주기비용이 높아질수록 TSS와 TN의 저감효율은 높아지는 것으로 나타났다. 이러한 연구결과는 비용효율적인 비점오염 저감시설을 설계하는데 유용하게 활용될 것으로 기대되며, 향후 LCC 모델의 기초자료에도 활용될 수 있을 것으로 판단된다.

• 한국환경복원기술학회지
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• 제13권6호
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• pp.25-38
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• 2010

This study focused on the analysis of satisfaction and preference of residents' for water space as a environmental friendly facility in residential complex. The purpose of this study is to serve design data of water space in residential complex, in order to make water space that residents' satisfaction are high. In this study, residents' satisfaction and preferences of water space in 5 residential complex were analyze through a questionnaire survey of residents. The major findings of the study are as follows. First, in terns of the need of the water space, 60.4% of the respondents answered that water space are need to improve the amenity. Secondly, in terms of satisfaction, 57.3% of the respondents have been satisfied with location of water space in the residential complex, and the maintenance satisfaction degree is above average level. Overall satisfaction degree is above average level too, but it is are not high as compared construction cost. Thirdly, in terms of preference, 26.5% of respondents have been prefer to the combined type of water space, and 25.9% of respondents prefer to dropping water type, and 25.9% of respondents prefer to flowing stream type. It appeared that the preference levels of 3 type is high similarly, so we can assume that residents prefer to moving water type because of having a feeling refreshed through the sound of water. The results of this study can be used as the design data of water space in residentialcomplex and expected to contributed in making the water space that residents' satisfaction are high.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2005년도 학술발표논문집
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• pp.102-107
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• 2005

All concrete structure in agricultural improvement project must satisfied durability, serviceability, safety. It is important for structure that satisfied these natures to good quality at design and construction step, and must continuous maintenance. Most of the concrete structures is construct at winter season, is contacted with water, has various type and sporadic in wide area. The objective of this study is to make the Concrete-Quality-Control diagram for agricultural infrastructure project using GIS. And, analyze the diagram with external factor(terrain, stream, economic etc.) to know the factor of concrete quality control.

• 한국수자원학회논문집
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• 제36권2호
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• pp.315-324
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• 2003

하천유지유량 설정에 최소한의 기준이 되는 갈수량을 결정하기 위하여 하천유량 자료를 검토하고 확률갈수량을 추정하였다. 확률갈수량은 모수적 방법과 비모수적 방법을 사용하여 산정하였으며, Monte Carlo 모의실험을 통하여 비교·분석하였다. 한강유역 13개 지점의 갈수량에 대한 빈도 해석을 실시한 결과, 유역 전체에 대한 확률분포 형은 3가지 분포형, 즉 2모수 gamma, 2모수 lognormal, 그리고 2모수 Weibull 분포가 한강 전지점의 주요 분포형으로 나타났다. 모집단과 같은 확률분포형의 상대편의와 상대평균제곱근오차가 가장 작게 나타났으며, 내삽범 위에서 비모수적 방법이 통계적 거동특성(상대편의와 상대평균제곱근오차)이 좋은 것으로 나타났다. RRMSE에 있어서 비모수적 방법중에서 PM 기법이 가장 작게 나타났으며, SJ 기법이 비모수적 방법 가운데 가장 크게 나타났다.

• 한국지형학회지
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• 제18권1호
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• pp.1-13
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• 2011

김해시 대동면 일대에는 자연배수를 위한 승수로, 안정적인 용수 확보를 위한 터널 굴착, 야주하천의 인위적 직강화, 일반적인 형태의 양·배수장 등, 범람원에서 볼 수 있는 각종 양·배수시설이 다양하게 나타나고, 이들 시설의 개발, 유지, 운영에는 범람원 지역의 지형 조건이 크게 작용하고 있음을 확인했다. 특히 운하천 유역의 경우, 운하천 취수문만 열면 자연 경사에 의해 얼마든지 낙동강 본류의 물을 양수할 수 있고, 연구지역에서 가장 큰 양수장인 월당양수장에서 낙동강 본류의 물을 직접 양수할 수 있다. 감내천은 한때 운하천(이전 하동천)의 상류였으며, 현재는 덕산승수로를 통해 낙동강으로 배수된다. 따라서 이러한 배수체계는 운하천 저지대의 홍수 피해 및 배수 부담을 덜어주고 있다.

• 대한환경공학회지
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• 제37권10호
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• pp.551-557
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• 2015

본 연구는 주암댐 유역을 대상으로 구축된 HSPF 결과를 활용하여 각 소유역별 비점오염원 부하량을 산정하여 비교함으로써 비점오염저감시설 우선 설치 대상지점을 평가하였으며 2011~2012년 BOD, TN, TP를 대상으로 모델 재현성을 검토된 결과를 활용하였다. 소유역별 비점오염부하량을 산정하여 비점오염저감시설 우선 설치 대상지점을 평가한 결과, BOD의 경우에는 2011년 평균 $8.8kg/day/km^2$, 2012년 평균 $9.1kg/day/km^2$, TN은 2011년 평균 $9.7kg/day/km^2$, 2012년 평균 $10.1kg/day/km^2$, TP는 2011년 평균 $0.30kg/day/km^2$, 2012년 평균 $0.33kg/day/km^2$으로 산정되었고, 보성강 상류에 위치한 소유역에서 상대적으로 높은 부하량이 유출되는 것으로 분석되었다. 특히, 봉화천 유역이 가장 우선순위가 높게 평가되었으며 미력천, 장평천, 율어천, 구암천, 석교천, 문덕천, 인천천, 봉내천 등의 순서로 평가되었으며 대체적으로 농업지역의 비율이 큰 소유역의 우선순위가 높은 것을 확인할 수 있었다.

• 한국구조물진단유지관리공학회 논문집
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• 제8권1호
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• pp.175-181
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• 2004

본 연구에서는 고속철도 ${\bigcirc}{\bigcirc}$역사 공사구간 중에 굴착구간에 인접하여 하천이 위치하고, 공사구간 좌측에는 항상 만수위 상태의 저수지가 위치하고 있어 지반굴착시 지하 5m 깊이에서 지하수위면이 발생하는 구간에 설치된 부력앵커의 거동특성에 관한 연구이다. 따라서 본 연구는 지하수위면이 발생하는 구간에서 설치된 부력앵커의 현장시험을 통해 시공시 영구적으로 지하수위에 의한 부력을 방지할 수 있는 부력앵커를 이용하여 구조물을 안정적으로 시공하고 지속적인 유지관리를 원활히 하고자 하는데 목적이 있다. 부력앵커 시험은 Bar Type Anchor를 Anchor의 길이와 규격별로 구분하여 인발시험을 실시하였다. 현장시험은 영구 앵커의 길이, Bar의 외경, 천공경을 변화시켜 가며 시험앵커 9본에 대한 시험을 수행하였다. 시험을 통해 앵커의 한계하중, 앵커체 바깥면의 인발저항, 하중 및 부착응력 분포, 앵커의 천공지경의 영향, 정착길이의 영향 및 지표면의 거동에 대하여 알아보았다. 그리고 부력방지용 Bar Type 앵커의 하중전달 및 파괴 메카니즘을 중심으로 앵커의 거동 특성에 대해 알아보았다.