• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.456-456
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• 2015

최근 집중호우 및 돌발홍수로 인한 물관련 피해가 늘어감에 따라 도시화된 유역의 물관리 연구에 많은 초점이 모아지고 있다. 도시 유역의 물순환에 대한 하나의 해결방법으로 각광받고 있는 LID(Low Impact Development)에 관한 많은 연구가 이루어지고 있다. 본 연구에서는 법정행정구역도를 따라 온천천 유역을 각 동별로 나누어 LID를 설치하였을 때 적용 효과가 가시적으로 나타나는 소유역을 확인하기 위하여 SWMM 모형을 통해 시뮬레이션을 실시하였다. LID 요소기술로는 토지피복에 따라 주택지에는 옥상녹화, 도로에는 투수성포장을 설치하여 각 동별로 LID 적용 전 후에 대한 유출량, 침투량, 첨두유량, 유출계수 등을 비교 및 분석하는 연구를 수행하였다. 온천천 유역 14개 동에 대한 분석을 실시한 결과, 유출량 감소율의 경우 수민동(85.24%), 거제동(83.23%), 명장동(82.81%), 침투량 증가율은 수민동(162.8%), 안락동(105.1%), 복산동(71.03%) 순으로 하천 주변의 거주지가 밀집된 지역에 가시적인 효과가 나타났으며, 첨두유량 감소율은 청룡동(81.82%), 장전동(80.37%) 부곡동(79.39%) 순으로 소유역의 경사가 급한 지형에 효과가 좋은 것으로 나타났다. 유출계수 감소율은 유출량 감소율의 경우와 마찬가지로 나타났다. 도시 유역에 보다 나은 물순환을 위하여 LID 요소기술을 설치할 때 저감시키거나 증가시키려는 매개변수를 확실히 선정하는 것이 LID 효과를 극대화 할 수 있다는 점을 확인하였다.

• Journal of the Korean Society of Propulsion Engineers
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• v.11 no.6
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• pp.9-17
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• 2007

This experimental study has been conducted to investigate the effect of the recirculation zone on the multi-slot film cooling in the ramjet combustor. The recirculation zone which is generated by the protrusion tip on the entrance of the coolant flow path affects on the first slot. Velocity fields, dimensionless temperature fields and adiabatic film cooling effectiveness on the downstream wall of the slot exit are measured. The results show that the film cooling performance is rapidly decreased after the slot exit by shear layer and high turbulence intensity between separated flows and coolant flows.

• 한국해양학회지
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• v.29 no.1
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• pp.64-81
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• 1994

The trend of physical oceanography research in Korea till 1992 is briefly described. Research papers and activities are reviewed and classified according to the research field and geographic area. so this work ca be served as a reference in planning future researches and surveys. Most of the research areas are confined to the nearshore around the Korean Peninsula and the research field do not extend far beyond the classic subjects of physical properties of water masses and tides. etc. Future researches should thus be oriented to the basin-scale circulation aiming at the national oceanographic tasks such as the formation of the Tsushima Warm current, circulation in the Yellow-East china Seas, and three dimensional circulation of the East (Japan) Sea.

• Journal of the Korean Recycled Construction Resources Institute
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• v.1 no.1
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• pp.67-75
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• 2013

Recently, the interest is increasing about the exposed concrete, accordingly, exposed concrete is expanding the use. However, concrete structures is difficult to apply the general concrete for exposed concrete, due to complex section and compact reinforcement, increasingly. Therefore, in this paper, for application of high fluidity concrete as exposed concrete, exposed high fluidity concrete using fly ash and lime stone powder was manufactured and observed quality property(fluidity properties, mechanical properties and Surface Properties) of exposed high fluidity concrete. The experiments are based on the OPC and LSP10, was evaluated Impact on the quality of concrete according to mixing ratio of FA(0, 10, 15 and 20). As a result, fluidity properties, mechanical properties and Surface Properties of exposed high fluidity concrete were satisfied to requirement conditions, fluidity and surface finishability was improved depending on mix of fly ash and limestone powder. Through this, we utilize of basic research data for development of high fluidity concrete for exposed concrete.

• Journal of the Korean Recycled Construction Resources Institute
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• v.10 no.2
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• pp.143-151
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• 2022

In this study the relative dynamic modulus and surface rebound hardness measurement methods were used for comparison to predict the occurrence of frost dam age on the concrete. From the test results, it was observed that the initiation of concrete dam age predicted by surface rebound hardness values was 200 cycles quicker than that of the relative dynamic modulus method in the W/C 70 specimens. In addition, it continuously provided data that showed the frost damage development of concrete surfaces according to increasing freeze-thaw cycles. This indicated that the frost dam age of the concrete could be found from the initial point of its occurrence by the surface rebound hardness measurement method. Similar results were also observed in W/C 60 and 50 specimens. Therefore, it is considered that surface rebound hardness method predicted the freeze-thaw damage well, regardless of water-cement ratio.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.20 no.4
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• pp.199-205
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• 2015

Nitrogen and phosphorus are the limiting elements for growth of phytoplankton, which is a major primary producer of marine ecosystem. Incidentally the stoichiometry of N/P of ocean waters, measured by the (nitrate + nitrite)/phosphate ratio converges to a constant of 16. This characteristic ratio has been used widely for the understanding the ecosystem dynamics and biogeochemical cycles in the ocean. In the East Sea, several key papers were issued in recent years regarding the climate change and its impact on ecosystem dynamic and biogeochemical cycles using N/P ratio because the East Sea is a "miniature ocean" having her own meridional overturning circulation with the appropriate responding time and excellent accessibility. However, cited N/P values are different by authors that we tried to propose a single representative value by reanalyzing the historical nutrient data. We present N/P of the East Sea as $12.7{\pm}0.1$ for the year 2000. The ratio reveals a remarkable consistency for waters exceeding 300m depth (below the seasonal thermocline). We recommend to use this value in the future studies and hope to minimize confusion for understanding ecosystem response and biogeochemical cycles in relation to future climate change until new N/P value is established from future studies.

• Journal of Chest Surgery
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• v.30 no.3
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• pp.326-329
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• 1997

Coronary artery bypass grafting(CABG) without cardiopulmonary bypass(CPB) is now an accepted technique of myocardial revascularization in selective cases of coronary arterial occlusive disease. The lesion was total(100%) occlusion of proximal right coronary artery(RCA) without any evidence of dis,Base in the rest of coronary arteries. Percutaneous transluminal angioplasty(PTCA) was tried but unsuccessful. We herein report a case of successful CABG to right coronary artery without CPB on a patient with complete occlusion of RCA and symptomatic wit minimal activity.

• Ocean and Polar Research
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• v.36 no.2
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• pp.111-119
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• 2014

This study examined the spatial and temporal variation of dissolved inorganic radiocarbon in the East Sea. Five vertical profiles of radiocarbon values were obtained from samples collected in 1999 in three basins (Japan Basin, Ulleung Basin, Yamato Basin) of the East Sea. Radiocarbon values decreased from 63- 85‰ at the surface to about -50‰ with increasing depth (up to 2,000 m) and were nearly constant in the layer deeper than 2,000 m in all basins. Radiocarbon values did not show significant basin-to-basin differences in the surface and the bottom layers. In the intermediate layer (200-2,000 m), however, they decreased in the order of Japan Basin > Ulleung Basin > Yamato Basin, which is consistent with the suggested circulation pattern in the intermediate layer of the East Sea. Radiocarbon was found to have decreased at ~2%/year in the surface water of the East Sea. In contrast, in the interior of the East Sea, radiocarbon values have increased with time in all three basins. In the Central Water, the annual increase rate was about 3.3‰, which is faster than the rates in the Deep and Bottom Waters. The radiocarbon in the Deep and Bottom Waters had increased until mid-1990s, after which time it has been almost constant.

• Journal of the Korean Recycled Construction Resources Institute
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• v.2 no.2
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• pp.68-75
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• 2006

The total production of the smelted copper reaches 450,000 tons per year, and the production of copper-related goods grows year by year owing to the extension of facilities and the development of production techniques. On the other hand, the volume of slag discharges by-produced at the time of copper smelting process is also on trend of increase. The by-produced copper smelting slag amounts to 700,000 tons a year, which is one and half times of the total smelted copper production. Accordingly nobody disagrees that comprehensive researches on how to deal with and how to reuse the accumulated smelting copper slag have to be encouraged. Even though the possible uses of the copper smelting slag have being made on various levels at present as materials for iron powder cement, sand-blasting and fire-proofing rock wool, but a considerable volume of the slag is abandoned as unnecessary by burying or piling up in careless in the open ground.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2000.05a
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• pp.94-96
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• 2000