• Journal of Korean Society of Coastal and Ocean Engineers
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• v.29 no.6
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• pp.389-398
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• 2017

The re-analysis on the stable weight of the concrete armor unit (CAU) at the roundhead and the suggestion of the covering range at the roundhead with the increased weight of CAU were conducted. Tetrapods were applied to the tests and the three dimensional hydraulic tests were performed. The test results for the stable weight at the roundhead area were similar to the guides from Korean Design Standard for Harbour and Fishery Port (MOF, 2014) and Coastal Engineering Manual (USACE, 2005). The investigation of covering range at the roundhead of rubble mound structures armoured with Tetrapods was suggested that the length of five times of the design wave height from the tip of the superstructure was needed and appropriate. Both sides of the superstructure should be covered with increasing weighted CAU to satisfy the stability at roundhead area.

• Journal of Life Science
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• v.13 no.5
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• pp.604-617
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• 2003

Candida albicans is one of the most common etiological agents in fungi-associated skin infections. There is an increase of candidiosis especially in the patient of acquired or induced immunodeficiency syndromes or in the event of long-term antibiotics and immuno-suppressor or cytotoxic therapies. To screen out reliable and effective anti-candidiosis agent, in this study, we have evaluated antifungal activity of 298 plant extracts against C. albicans. Based on the results of disc-paper method and determination of minimal inhibitory concentration, fifteen extracts were finally selected as possible sources of anti-candidiosis agent. Especially, six different plant extracts, such as Rubus parvifolius, Euphorbia pekinensis, Coptis chinensis, Eugenia aromaticum, Paeonia lactiflora var. hortensis and Paeonia suffruticosa showed strong antifungal activity against C. albicans, not to S. cerevisiae. These results suggested that medicinal and wild plants could be the potential source of antifungal agent.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.105-105
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• 2021

본 연구에서는 2차원 비선형 천수모형과 수심평균된 스칼라 이송모형을 해석하는 수치모형에 대해 기술하였다. 수치모형의 정확성을 보장함과 동시에 안정성을 높이기 위해 유한체적법, 플럭스 재구성 및 minmod 제한자를 사용하였다. 비선형 천수방정식의 이송항과 바닥 경사항은 계산된 수심의 양수 보존과 흐름의 정상 상태를 보장하기 위한 second order well-balanced positivity preserving central-upwind method를 이용하여 수치적으로 이산화되었다. 마찬가지로, 이송-확산 방정식 내 이송항은 동일한 2차 풍상차분법을 통해 수치적으로 풀이하였다. 격자점 경계면에서의 불연속으로 인한 수치진동을 방지하기 위해 이송항의 계산에 포함된 보존항의 차이로 인해 발생하는 스칼라의 수치확산을 최소화하기 위해 무차원의 비소산함수를 도입하였다. 또한, 확산항은 유한차분법을 이용하여 이산화하였다. 제안된 수치모형은 시간미분항의 계산을 위해 오일러 기법을 적용하여 계산된 수심 및 스칼라의 양수 보존여부와 함께 정지된 흐름의 정상 상태의 보존여부를 확인하였다. 제안된 수치모형의 해석 정확성을 평가하기 위해 1, 2차원 공간 내 다양한 흐름 조건에서의 해석해를 이용한 3개의 벤치마크 테스트를 수행하였다. 평균 제곱근 오차(Root Mean Squared Error, RMSE)를 산정하여 수치모형의 성능을 정량적으로 평가하였으며, 비소산함수를 적용함에 따라 스칼라의 수치확산이 감소하게 되었음을 확인하였다. 또한, 세 차례의 벤치마크 테스트 결과는 공통적으로 수치모형에 의해 계산된 결과값이 비소산함수를 고려함에 따라 해석해와 잘 일치함을 확인하였다.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.218-218
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• 2021

최근 환경 문제과 관련하여 건설 분야에서 발생하는 환경적인 부담을 줄이고자 다양한 재활용 소재들에 대한 연구에 대한 관심이 증가하고 있다. 특히 폐기물 중 생활계에서 발생하는 폐플라스틱은 '쓰레기 대란'이라는 사회적 문제로 대두된 사례가 있다. 생활계에서 발생하는 폐비닐은 다양한 조성으로 이루어져 재활용 대상에서 제외되기 때문에 매립 또는 소각되는 플라스틱의 양을 줄이고 재활용율을 늘릴 수 있는 연구가 필요하다. 본 연구는 생활계에서 발생하는 폐비닐을 융용시켜 무기첨가제 등을 한 복합 Alloy를 생산한다. 또한 재생이 가능한 복합 Alloy를 압출 또는 사출 과정을 통해 테트라포드의 형태를 만들 수 있는 Preform으로 가공하는 공정연구 하였으며 이러한 Preform을 해안 및 항만에서 사용되는 콘크리트 피복재에 적용하였을 때 플라스틱 소재와 콘크리트 소재의 비중의 차이로 인해 발생하는 안정성을 정량적으로 평가하는 수리모형 실험를 수행하였다.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.1436-1437
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• 2015

"국가를 당사자로 하는 계약에 관한 법률" 시행령 제9조 1항 제3호 및 같은 법 시행규칙 제5조 제2항에 근거 전기공사의 예정가격의 결정기준은 (1)거래실례가격 (2)표준품셈 (3)표준시장단가 (4)견적가격 등 4가지 방법을 사용하고 있다. 특히 표준시장단가제도는 이미 수행한 공사의 계약단가만을 고려하여 발표하는 "실적공사비"제도를 계약단가, 입찰단가, 시공단가 등을 고려한 "표준시장단가"제도로 2015년 3월 1일부로 개정되었다. 제도는 시행되었으나 표준시장단가의 산정기준, 절차 및 방법 등 세부적인 제도가 미흡한 상황이다. 따라서 과거 실적공사비 산정방식을 검토하되, 계약단가, 입찰단가, 시공단가 등을 고려한 합리적인 표준시장단가의 산정방식을 제시함으로써, 예정가격결정시 적정공사비를 확보하고, 원 하도급간의 거래가격 투명성 및 객관성을 통해 전기공사의 품질 및 안정성이 확보될 것으로 사료된다.

• Journal of Navigation and Port Research
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• v.45 no.3
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• pp.87-94
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• 2021

The IMO has adopted emission standards that strictly restrict the use of bunker C oil for vessels. Accordingly, research and bunkering pilot projects for LNG fueled ships are being actively carried out, which is expected to substantially reduce environmental pollution. In this study, we have adopted the turret moored Floating LNG Bunkering Terminal (FLBT) designed to receive the LNG from LNGCs and to transfer LNG to LNG bunkering shuttles in ship to ship moored condition. Numerical simulations have been performed with a 1-year return period of wind, wave, and current. Damping values of numerical model were adjusted from the results of model tests to obtain accurate simulation results. The results confirm safe berthing operation during the 1-year return period of environmental condition. Safety depends on the direction of environment, with increasingly stable operation facilitated by the application of heading-control function of FLBT to avoid beam-sea conditions.

• Journal of Korea Port Economic Association
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• v.25 no.3
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• pp.303-320
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• 2009

Korea has achieved a remarkable growth by pursuing externally-oriented growth policy since 1960s. That is, we imported raw materials and spare parts, manufactured them into products and exported them, which led to successful economic development. Therefore, our marine business has played an important roles as one of key industries. The development of marine business has contributed to efficient distribution and cost reduction in addition to production of added value and creation of employment creation, which improved external competitive power. In spite of economic importance of marine business, national perception on it is in general low and its developmental conditions are considerably poor. Therefore, this study aims to speculate the effect of Port-related business on regional economy using regional input-output tables.

• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.2
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• pp.111-118
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• 2013

This paper suggested the improvement of marine environmental impact assessment in eastern coast as analyzing consultation on the coastal area utilization for development of ports and fishing harbors for 3years in the east coast. The results of survey are only 3cases, 12cases and 16cases each for ocean currents, wave and sounding data. However, for development of ports and fishing harbors in eastern coast, ocean characteristics in eastern coast different than in the West Sea, South Sea is considered to marine environmental impact assessment. For development of ports and fishing harbors in east coast where the influences of ocean currents, wind-driven current and waves are dominant, the effect of the current should be considered to improve the reproducibility of tidal current. The wave should also be considered as an assessment criteria to obtain the validity of project such as harbor tranquility, functionality of breakwaters and stability. In addition, sediment inflow in river and exact water depth data of the ocean should be applied to numerical modeling and set wave-induced current to external force of sediment transport to predict the problems such as the harbor siltation and the coastal erosion considering ocean characteristics in the east coast.

• Korean Journal of Psychosomatic Medicine
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• v.29 no.2
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• pp.86-94
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• 2021

Objectives : The risk of weight gain is high when using antipsychotic drugs, and the prevalence of obesity in people with mental illness is high. Obesity management in psychiatric patients is important because obesity causes various complications and lowers treatment adherence and quality of life. Methods : In this review, we summarized the management strategies for obesity that can occur when using antipsychotic drugs through a web search. Results : Evaluate obesity-related risk factors and related indicators from the beginning of treatment, and conduct regular monitoring. If an antipsychotic drug is used and obesity is induced, a change to a drug with a low metabolic risk may be attempted. Sufficient interventions are also needed on the need to manage obesity, a healthy diet, and exercises in patients and their families. If weight loss is not achieved and obesity-related complications are associated, the use of anti-obesity drugs may be considered. Pharmacological treatment approaches should be carefully considered. Conclusions : Non-pharmacological and pharmacological therapies can be applied to manage weight gain and obesity caused by the use of antipsychotic drugs. When using anti-obesity drugs, the characteristics of mental disorders, drug safety, and drug interactions should be considered.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.5
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• pp.651-655
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• 2018

In this paper, based on an augmented Lyapunov-Krasovskii functional(LKF) with time-delay product quadratic terms, the stability result in the form of linear matrix inequality(LMI) is proposed. In getting an LMI result, the free matrix based integral inequality is used. Finally, two well-known numerical examples are given to demonstrate the usefulness of the proposed result.