• 한국유체기계학회 논문집
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• 제2권4호
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• pp.40-47
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• 1999

A hot water layer (HWL hereinafter) was installed at the depth of 1.2 m from the pool surface to reduce the radiation level at the pool top. After the HWL system was improved by the replacement of the filter with the Ion Exchanger to capture the Na-24, to purify the pool water of HWL and finally to reduce the radiation at the pool top. It was confirmed by the performance test of the pump and the measurement of the pressure difference through the Ion Exchanger and the strainer, that the flow characteristics of HWL system was not adversely affected after the system modification. Also the flow analysis using the pressure loss coefficients of the Ion Exchanger and strainer, calculated by the Darcy formula, could predict the flow variations by pressure changes within $10\%$ error in comparison with the field test results. It was also confirmed that HWL was maintained with the depth of 1.2 m from the pool surface because each electric water heater was electrically and thermodynamically maintained at 30 kW and the temperature of HWL was maintained with $5^{\circ}C$ higher temperature than that of pool water. Finally, it was confirmed that the pool top radiation was saturated and stabilized below 10000 nG/hr within 24 hours as the ion exchanger captured the main nucleus, Na-24 and purified the pool water of HWL.

• 한국제4기학회지
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• 제13권1호
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• pp.53-65
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• 1999

기후변화와 이에 따르는 식생변화, 인위적인 토지이용 변화 등 '지역환경생태시스템의 변화'에 대한 '지역 물수지변화' 추정은 오직 필자가 개발한 BROO $K_{TOP}$과 같은 '물리기반 물수지 모델(Physical based Water Balance Model)'류에 의해서만 가능하다. 본 연구에서는 독일 중북부 농업지대와 산림지대에 대해서 $BROOK_{TOP}$ 소프트웨어를 이용하여 정립된 물리기반 지역물수지모델에 독일 포츠담 기후변화연구소(PIK) 시나리오와 체코 프라하대학에서 개발한 중부유럽 대상 GCM 기후변화 시나리오를 적용하여 물수지변화를 추정하였다. 이와 같은 기후와 지표.지하조건을 고려 한 지구온난화에 따른 수자원변화 예측시스템 개발은 하천수$\cdot$지하수 개발 및 수질 관리, 농업경작관리, 환경생태계 관리, 자연 재해 관리, 토지이용계획 및 지역개발계획 등을 위한 시스템개발의 기반이 된다

• 디지털융복합연구
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• 제15권10호
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• pp.525-535
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• 2017

본 연구는 최근 워터파크와 관련된 키워드를 통해 소비자 인식, 워터파크 현황을 살펴보고자 한다. 본 연구는 네이버와 다음을 수집채널로 선정하였으며, 키워드는 '워터파크'를 사용하였다. 자료 분석기간은 2015년 1월 1일부터 2016년 12월 31일까지 총 2년간을 연구기간으로 한정하였다. 분석결과 첫째, 빈도수를 살펴본 결과, 2015년 몰래카메라, 롯데워터파크, 검거, 용의자, 김해 2016년 롯데워터파크, 물놀이, 여름, 개장, 입장권 순으로 나타났다. 둘째, 연결정도 중심성 분석결과, 2015년 몰래카메라, 검거, 용의자, 여성, 샤워실 2016년 물놀이, 롯데워터파크, 여름, 원마운트, 입장권 순으로 나타났다. 셋째, N-GRAM 네트워크 그래프를 실시한 결과, 2015년 워터파크/몰래카메라, 몰래카메라/몰래카메라, 용의자/검거, 김해/롯데워터파크, 워터파크/용의자, 2016년 원마운트/워터파크, 김해/롯데워터파크, 워터파크/입장권, 워터파크/워터파크, 워터파크/개장 순으로 나타났다. 넷째, CONCOR분석을 실시한 결과, 2015년 3개의 그룹과 2016년 2개의 그룹이 형성되었다.

• 대한조선학회논문집
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• 제42권6호
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• pp.559-565
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• 2005

As the wave impinges on and overtops the structure, a large highly aerated region is created in front of the structure and water splashs on top of the structure. The broken wave in front of the structure and associated green water on top of the structure are highly aerated containing not only a large number of bubbles but also very large sizes of bubbles. In this paper, the velocity field of the highly aerated region and the splashing water on the top is measured using a modified PIV method incorporating the traditional PIV method with the shadowgraphy technigue by correlating the ' texture ' of the bubble images. The velocity fields of a plunging wave impacting on a structure in a two-dimensional wave flume is measured. It is found that the maximum fluid particle velocity in flout of the structure during the impinging process is about 1.5 times the phase speed of the wave, while the maximum horizontal velocity above the top is less than the phase speed, It is also found that the dam breaking solution does not work well in predicting the green water velocity.

• 한국패류학회지
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• 제27권4호
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• pp.299-306
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• 2011

This paper examines relation between growth of adult top shell and their selectivity over different marine algae. For the study the top shell density and the algal species in different depth were surveyed by SCUBA. To test selectivity over different types of algae, five algal species including Ecklonia cava, Undaria pinnatifida, Ulva spp, Gelidium amansii and Sargassum spp were provided to top shells in indoor water tank condition. In the field survey, the wet weight of Ecklonia cava was significantly (r = 0.612, p < 0.05) correlated to the shell length (SL) of top shell. In the indoor water tank experiment conducted over 12 hours after sunrise, adult top shell (SL > SL 4.5 cm) tended to select Ecklonia cava and Undaria pinnatifida, which are common and abundant algal in the subtidal waters in Jeju Island. Our field survey and the indoor experiment suggest that E. cava and U. pinnatifida could be food preferred by adult top shell in its habitat.

• 농촌계획
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• 제23권4호
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• pp.111-126
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• 2017

This study analyzes the impacts of agricultural water shortages in Korea using a combined top-down and bottom-up model. A multi-region multi-output agricultural sector model with detailed descriptions of production technologies and water and land resource constraints has been combined with a standard CGE model. The impacts of four different water shortage scenarios were simulated. It is shown that an active adaptation of crop choices occurs in even the regions with relatively abundant water resources in order to respond to the change in relative output prices caused by water shortages. We found that although the losses in production values are not quite large despite water shortages due to the price feedbacks, the loss in GDP is substantial. We show that our combined approach has advantages in deriving region and product specific production effects as well as the overall GDP loss effect of water shortages.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 봄 학술발표회 논문집
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• pp.799-804
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• 2000

The joint treatment of concrete is one of the technical problems in top down construction method. Joints created wit the top down construction result in serous weakness from the aspects of both structural and water-barrier function. Several case studies for the insepction of top down construction joints of column in SRC structure using radar and infrared thermography method. The advantages and limitations of these methods for non-destructive inspection in top own construction joints are investigated.

• 한국응용과학기술학회지
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• 제24권4호
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• pp.399-409
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• 2007

Characteristics of polyaniline anti-corrosive coatings with various primer coating resins(epoxy resin, urethane resin, and others) and top coating resins(epoxy and acrylic urethane resins) were investigated through adhesion, acid resistance, alkaline resistance, water resistance, and anti-corrosion tests. As a result, the anti-corrosive properties of the prepared coatings using polyaniline varied with the types of primer and top coating resins. In this condition, the properties of adhesion, chemical resistance, and water resistance were found to be very satisfactory when using emeraldine base (EB) of polyaniline blended with single-packaged urethane and acrylic urethane resins as the primer coatings, and using acrylic urethane resin as the top coatings. Also, the anti-corrosive function of these anti-corrosive coatings was well preserved for 1000 hr in the salt spray experiment.

• 상하수도학회지
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• 제19권2호
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• pp.209-213
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• 2005

Slow sand filtration processes amended with 5 and 10cm GAC layers at top was compared to same process at bottom in a pilot study for humic substances removal. In case of 5cm GAC layer, the process amended at bottom was superior to the process at top in DOC and UV254nm removal and same trends were observed in case of 10cm GAC layer. Head loss developments of the process GAC at bottom were higher than the process GAC at top so that maintenance of the process GAC at top is easier than the process GAC at bottom.

• Journal of Microbiology and Biotechnology
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• 제23권12호
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• pp.1774-1778
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• 2013

Methylotrophs within biological activated carbon (BAC) systems have not received attention although they are a valuable biological resource for degradation of organic pollutants. In this study, methylotrophic populations were monitored for four consecutive seasons in BAC of an actual drinking water plant, using ribosomal tag pyrosequencing. Methylotrophs constituted up to 5.6% of the bacterial community, and the methanotrophs Methylosoma and Methylobacter were most abundant. Community comparison showed that the temperature was an important factor affecting community composition, since it had an impact on the growth of particular methylotrophic genera. These results demonstrated that BAC possesses a substantial methylotrophic activity and harbors the relevant microbes.