• 대한토목학회논문집
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• 제32권1B호
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• pp.1-7
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• 2012

본 연구에서는 준 2차원 수치모형인 GSTARS를 이용하여 형산강의 하상변동모의에 적합한 최적 유사량공식을 산정하고자 하였다. 모형의 검보정을 위한 유사량, 하상재료 및 하천지형자료를 현장조사를 통해 취득하였다. 현재까지 널리 적용되는 유사량 공식들에 대하여 장기하상변동 모의결과의 실측치에 대한 평균오차, 상대오차, 평균제곱오차, 상대제곱근오차, 불일치율, 그리고 Nash-Sutcliffe 효율계수를 비교한 결과, Laursen(1958)공식이 형산강의 장기하상 변동을 모의하기 위한 가장 적합한 유사량공식으로 판단되었다.

• 대한한방내과학회지
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• 제27권3호
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• pp.572-578
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• 2006

Objectives : This study investigated whether taking herbal medicine over the long-term had any side effects of liver damage. Methods : We checked LFT levels of the 58 admitted patients. Results : When we compared admission LFT levels with discharge LFT levels, we found the levels of AST, ALT and LDH had decreased. This test showed statistically significant decrease. When we compared admission LFT levels with discharge LFT levels, we found the increases of discharge LFT levels fell within the standard deviation. When we compared admission LFT levels with discharge LFT levels, we found the levels of LFT did not increase as much as two standard deviations. Conclusions : According to the above results, taking herbal medicine over a long-term did not have any side effects of drug-induced liver damage.

• 지역사회간호학회지
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• 제32권3호
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• pp.382-395
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• 2021

Purpose: The purpose of this qualitative study was to explore the transition experiences of the elderly from long-term care hospitals to their homes. Methods: The participants were eight elderly medicaid beneficiaries, who had been the subjects from the community care project in Korea. The data were collected with one-on-one interviews from April to November in 2020, and analyzed by phenomenological steps. Results: The seven themes derived in this study were 'Space to escape', 'Reliable supporter opened the way to discharge', 'Comfortable life at home', 'Obstacles to independent life', 'Struggling to live alone', 'Fence for community life', and 'Energizing in daily life' Conclusion: The results revealed the positive aspects of Community Care program in Korea. However, it is suggested that active communication between hospitals and community care institutions, and improvement of home environment to live in the community before discharge should be required. And system revision is needed to adjust activity in their home and support health problems of the elderly in the early stage of discharge. The results of this study can be referred to as the foundation of transitional care for the elderly.

• 한국환경과학회지
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• 제24권12호
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• pp.1691-1703
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• 2015

When constructing tunnels, it is important to understand structural, geological and hydrogeological conditions. Geumgeong tunnel that has been constructed in Mt. Geumjeong for the Gyeongbu express railway induced rapid drawdown of groundwater in the tunnel construction area and surroundings. This study aimed to analyze groundwater flow system and baseflow using long-term monitoring and groundwater flow modeling around Geumgeong tunnel. Field hydraulic tests were carried out in order to estimate hydraulic conductivity, transmissivity, and storativity in the study area. Following the formula of Turc and groundwater flow modeling, the annual evapotranspiration and recharge rate including baseflow were estimated as 48% and 23% compared to annual precipitation, respectively. According to the transient modeling for 12 years after tunnel excavation, baseflow was estimated as $9,796-9,402m^3/day$ with a decreasing tendency.

• 한국항해항만학회지
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• 제44권2호
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• pp.128-135
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• 2020

Long-term shipping contracts represent the cooperative and coexisting relationships between the shipping and steel industries. Yet, differences between the contract forms for iron ore and steel products have emerged. Specifically, the large proportion of consecutive voyage charters (CVC) is being applied in the iron ore trade, whereas the contract of affreightment (COA) is proportionally higher for shipping steel products. The literature review and in-depth interviews in this study identified through the research model, the characteristics of the shipping and market structure in both markets have significantly contributed to the preference of different long-term contracts. It has been determined that the mutual oligopoly market structure and the characteristics of shipping such as, the small number of suitable vessels in the market, the single fixed load/discharge ports, the long-distance voyages, and the potential risks for fatal accidents because of cargo liquefaction, for the iron ore trade, provide higher contribution to the preference of CVC contracts. In contrast, the consignor oligopoly market structure and the shipping characteristics, such as the greater number of suitable vessels available in the market, the variation in ports, the cargo quantity per shipment, the various load/discharge ports, and the need for experienced carriers for steel product loading in the steel product trade has shown higher preference on the COA contracts as the consignors with superiority over the shipowners, resulting in favorable contract types and conditions for the consignors.

• Nuclear Engineering and Technology
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• 제28권3호
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• pp.257-264
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• 1996

The conventional Equipment Environment Qualification (EEQ) envelope is developed based on the containment responses during the design basis events. The Safety Depressurization System (SDS) design without In-containment Refueling Water Storage Tank (IRWST) adopted in the Ulchin 3&4 challenges the conventional EEQ envelope during long term Feed and Bleed (F&B) operation due to the direct discharge of high mass and energy into the containment. Therefore, it is necessary to confirm that the containment pressure and temperature history during the long term F&B operation does not violate the conventional EEQ envelope. However, this subject has never been quantitatively assessed before. To investigate the success path of long term F&B operation this paper analyzes the thermal hydraulic response of the containment and Reactor Coolant System (RCS) until the completion of depressurization and cooldown of RCS into Shutdown Cooling System (SCS) entry condition. It is found that the SCS entry condition can be reached within 6 hours without violating the EEQ curve by proper operation of SDS valves, High Pressure Safety Injection (HPSI) pumps and active Containment Heat Removal System (CHRS). The suggested strategy not only demonstrates the feasibility of long term F&B operation but also can be utilized in the preparation of Emergency Procedure Guidelines (EPGs)

• 대한임상독성학회지
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• 제18권1호
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• pp.18-25
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• 2020

Purpose: We studied the impact of arterial oxygen tension (PaO₂) on the long term neurologic outcome in patients with acute carbon monoxide poisoning. Methods: The study population included 311 patients who presented to emergency department with acute CO poisoning from January 2015 to January 2018. These patients underwent arterial blood gas testing at the time of presentation. The baseline demographic, clinical, laboratory, and clinical outcome data were recorded. The primary outcome of interest was the long term neurologic status. Results: The normoxia group was significantly older and it had a higher incidence of diffusion weighted MRI abnormality, and this group needed multiple HBO sessions compared to the group with moderate or severe hyperoxia. Also, the incidence of altered mentality at discharge was higher in the normoxia group than that of the moderate hyperoxia group. The incidence of a poor long term neurologic outcome was 11.3%. The incidence of a poor long term neurologic outcome decreased as the PaO₂ increased. The PaO₂ was significantly lower in patients with a poor long term neurologic outcome than that of the patients with a good outcome 198 (165.2 to 231.1) mmHg in the good outcome group vs. 154 (119-162) mmHg in poor outcome, p<0.001). In multivariate logistic regression analysis, PaO₂ was selected as an independent factor of the poor long-term neurologic outcome (OR 0.981 (95% CI: 0.968 to 0.995)) Conclusion: Higher PaO₂ was independently associated with a lower incidence of a poor long-term neurologic outcome.

• 한국물환경학회지
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• 제27권6호
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• pp.841-847
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• 2011

In this study, a method to determine the design capacities of nonpoint source (NPS) pollutant treatment facilities in urban areas was suggested. A facility capacity to treat 80 percent of total SS discharge was estimated by 2-year rainfall - runoff - build-up and wash-off simulation at Goonja drainage district in Seoul. For wash-off simulation, four wash-off models (EMC, RC, EXP, and Joo model) were used. As the results, 80 percent of total SS discharge could be treated with only 7.7~31.4% facility capacity of peak flow. The suggested method and results will provide a guideline to determine design capacities of NPS pollutant treatment facility in urban areas.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2020년도 학술발표회
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• pp.327-327
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• 2020

Increase in Earth's surface temperature, higher rainfall intensity rate, and rapid changes in land cover are just some of the most evident effects of climate change. Flooding, and river sedimentation are two inevitable natural processes in our environment, and both issues poses great risks in the dam industry when not addressed properly. River sedimentation is a significant issue that causes reservoir deposition, and thus causes the dam to gradually lose its ability to store water. In this study, the long-term effects of climate change on the sediment discharge in Yongdam Dam watershed is analyzed through the utilization of SWAT, a semi-distributed watershed model. Based from the results of this study, an abrupt increase on the annual sediment inflow trend in Yongdam Dam watershed was observed; which may suggests that due to the effects of climate change, higher rainfall intensity, land use and land cover changes, the sedimentation rate also increased. An efficient sedimentation management should consider the increasing trend in sedimentation rate due to the effects of climate change.

• 한국수자원학회논문집
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• 제53권5호
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• pp.357-367
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• 2020

미계측 유역의 수문순환이나 수질을 모의하는 것은 매우 어려운 것이 현실이며 특히 장기간에 걸쳐 모의를 해야 하는 경우에는 더욱 그러하다. 본 연구에서는 미계측 유역인 평화의댐 유역을 대상으로 물리적인 과정 기반의 분포형 수문 모형 GSSHA의 장기 유출과 수질 모의에 대한 적용성을 검토하였다. 분포형 유역 모형 GSSHA를 평화의댐 유역에 적용하여 유량과 수질 모의치를 실측치와 비교한 결과 소규모 호우로부터의 첨두유량을 과대하게 모의하거나 실측된 수질 자료와 일부 구간에서 다른 경향성을 보이는 등 일부 불일치하는 사항들이 나타났으나 모의된 주요 호우의 첨두유량과 기저유출의 전반적인 수문곡선 형태는 비교적 양호한 것으로 나타나 실무에서의 적용 가능성이 있는 것으로 판단하였다.