• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2021년도 학술발표회
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• pp.145-145
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• 2021

Water distribution networks (WDNs) are designed to satisfy water requirement of an urban community. One of the central issues in human history is providing sufficient quality and quantity of water through WDNs. A WDN consists of a great number of pipelines with different ages, lengths, materials, and sizes in varying degrees of deterioration. The available annual budget for rehabilitation of these infrastructures only covers part of the network; thus it is important to manage the limited budget in the most cost-effective manner. In this study, a novel pipe replacement scheduling approach is proposed in order to smooth the annual investment time series based on a life cycle cost assessment. The proposed approach is applied to a real WDN currently operating in South Korea. The proposed scheduling plan considers both the annual budget limitation and the optimum investment on pipes' useful life. A non-dominated sorting genetic algorithm is used to solve a multi-objective optimization problem. Three decision-making objectives, including the minimum imposed LCC of the network, the minimum standard deviation of annual cost, and the minimum average age of the network, are considered to find optimal pipe replacement planning over long-term time period. The results indicate that the proposed scheduling structure provides efficient and cost-effective rehabilitation management of water network with consistent annual budget.

• BMB Reports
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• 제39권4호
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• pp.406-411
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• 2006

Signaling lymphocyte activation molecule (SLAM; also known as CD150) is a newly identified cellular receptor for measles virus (MV). The interaction between MV Haemagglutin (MVH) and SLAM is an initial step for MV entry. We have identified several novel SLAM binding sites at residues S429, T436 and H437 of MVH protein and MVH mutants in these residues dramatically decrease the ability to interaction with the cell surface SLAM and fail to co-precipitation with SLAM in vivo as well as malfunction in syncytium formation. At the same time, K58, S59 and H61 of SLAM was also identified to be critical for MVH and SLAM binding. Further, these residues may be useful targets for the development of measles therapy.

• Journal of Power Electronics
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• 제17권5호
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• pp.1288-1297
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• 2017

The estimation of the remaining useful life (RUL) of lithium-ion (Li-ion) batteries is important for intelligent battery management system (BMS). Data mining technology is becoming increasingly mature, and the RUL estimation of Li-ion batteries based on data-driven prognostics is more accurate with the arrival of the era of big data. However, the support vector machine (SVM), which is applied to predict the RUL of Li-ion batteries, uses the traditional single-radial basis kernel function. This type of classifier has weak generalization ability, and it easily shows the problem of data migration, which results in inaccurate prediction of the RUL of Li-ion batteries. In this study, a novel multi-kernel SVM (MSVM) based on polynomial kernel and radial basis kernel function is proposed. Moreover, the particle swarm optimization algorithm is used to search the kernel parameters, penalty factor, and weight coefficient of the MSVM model. Finally, this paper utilizes the NASA battery dataset to form the observed data sequence for regression prediction. Results show that the improved algorithm not only has better prediction accuracy and stronger generalization ability but also decreases training time and computational complexity.

• 응용통계연구
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• 제26권3호
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• pp.531-547
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• 2013

연생모형(multiple life model)은 보험계약에서 두 명 또는 그 이상의 피보험자들의 사망 또는 생존의 상태에 따른 보험금을 지급하는 보험 상품의 보험료 결정 및 리스크 관리를 위한 모형이다. 본 논문에서는 부부 가입자 중 마지막 사망자가 발생할 때까지 연금이 지급되는 연생보험의 대표적인 상품인 역모기지를 살펴보고자 한다. 역모기지 상품은 만 60세 이상의 고령자가 소유주택을 담보로 거주하면서 일정액을 대출받지만 대출금을 다시 상환하지 않는 금융상품으로 부부 가입의 경우 대출 기간의 확률분포를 적용하기 위해서는 연생모형을 적용해야만 한다. 그러나 현행 역모기지 상품에 있어서 대출한도 및 월지급금 산출 시 연생모형이 적용되지 않고 있으며 우리나라의 경우에는 국민 생명표 상의 여자 사망률을 대출 종료(연금지급종료)확률로 활용하고 있다. 여자의 사망률을 이용하는 이유는 보수적인 관점에서 대출 종료 시점을 예측하기 위해 일반적으로 남자보다 여자가 더 수명이 길다는 점 때문이다. 고령화로 인해 수명이 점점 길어지는 추세이기 때문에 역모기지와 같이 계약기간이 확정되어 있지 않은 보험 상품의 경우 특히 더 계약 종료 시점에 대한 확률분포가 리스크 관리를 위하여 중요하다. 본 논문의 의의는 역모기지의 발행기관 및 보증기관의 적정한 월지급금 지급과 차후 월지급금의 과대지급으로 인한 지급불능을 방지하기 위해 현행 사용하고 있는 모형의 위험률에서 연생 모형으로 변경할 필요성을 실증분석을 통하여 제시한다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 C
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• pp.1408-1410
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• 1997

Arrhenius plots are useful in predicting long-term use temperatures of organic materials and in choosing parameters for accelerated aging. The effects of antioxidant on the heat resistance and temperature index of EPDM rubber used for electrical insulation were investigated. The short-time points were obtained by 50% retention of elongation at break.

• 생명과학회지
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• 제14권3호
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• pp.441-444
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• 2004

본 연구는 피브린의 무게를 측정하는 방법에 의하여 간단하고 단순하게 트롬빈활성을 측정하는 방법을 확립하기 위하여 수행되었다. 이 새로운 트롬빈측정 법은 트롬빈이 기질인 피브리노겐과 반응 후 생성된 피브린의 무게를 측정한다. 피브린의 생성은 사용한 트롬빈의 효소활성, 반응온도, 반응시간 및 원심분리의 시간에 의존하였다. 피브린의 생성은 37$^{\circ}C$에서 트롬빈활성이 1.0 unit/ml 이내, 4.0mg/ml의 피브리노겐 농도 및 반응시간이 5분 이내에는 직선적으로 증가하였다. 그리고 생성된 피브린은 3,000$\times$g에서 5분간 원심분리의 경우에 안정하였다. 이 새로운 피브린 측정 법은 트롬빈을 저해하는 천연물질을 탐색하는데 유행하게 사용될 것으로 기대된다.

• 생명과학회지
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• 제16권1호
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• pp.156-161
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• 2006

The essential oil of Nardostachys jatamansi (Valerianaceae), which has been used for a long time in aroma therapy, was investigated after inhalation or oral administration for its analgesic effect, anticonvulsant action, hypnotic effect and in vitro inhibitory activity on monoamine oxidase. This fragrance oil showed a significant analgesic effect in the phenylquinone-induced .writhing test, suppressed the convulsion induced by pentylenetetrazole and lengthened the pentobarbital-induced sleeping time in a time-dependent manner after fragrance inhalation or dose-independently by oral administration. Its inhibitory activity on monoamine oxidase was remarkable, showing $49.4\%$ inhibition at a concentration of 5.0 mg/ml. Six new terpenes with seven known compounds were detected by our GC-MS analytical conditions used. As a result, the essential oil fragrance of Nardostachys jatamansi would be clinically useful for a sedative by either inhalation or oral administration.

• 한국생활과학회지
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• 제22권2호
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• pp.375-389
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• 2013

This survey was conducted to compare the housewife's food habit and food purchase behavior on healthy dietary life. The questionnaires were collected from 151 working housewives and 159 housewives in Daejeon. The average meal time was 20~30 min., 67.6% of respondents ate breakfast and bap with guk(72.9%) was the most favourite foods. Almost half of them ate egg, fruit, vegetable everyday. They concerned highly about less intake of frozen foods(64.2%) and food additives(61.6%) for wellbeing dietary life. Because of close distance and various foods items, big discount store was chosen as food purchase place. The most considering purchase factor was food additives in working housewife and nutrition in housewife(p<0.05). In grocery shopping, working housewife considered children and their husbands(p<0.05). The most important purchase factor was the freshness in vegetables fishes fruits seaweeds eggs. TV or Radio was utilized the most frequently to obtain the useful knowledge on healthy foods. It is suggested that practical information should be offered housewives to purchase proper foods within their income and to manage dietary life according to their family's health condition.

• 한국주거학회논문집
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• 제12권2호
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• pp.181-190
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• 2001

The purpose of this study is to analysis web sites which relate to housing environment on Internet and to suggest guidelines which are needed in digital life. Data are in 53 web sites searched by housing environmental word such as people, living, town and so on. The web sites are analyzed by key words. The results of this study were as follow: The web sites are divided into e-housing community, e-housing management, e-housing workplace and e-housing design. These are the digital life of new type. E-housing community sitess key words are 3D virtual world, chatting, information, service, community etc. E-housing community is related to making new wired community cross time and space. E-housing management sitess key words are guard management, apartment management, building management etc. E-housing management sites provide the useful information of housing management. E-housing workplace sitess key words are virtual office. conference etc. E-housing workplace sites enable us to work in cyberspace. E-housing design sitess key words are design, interior, furniture etc. E-housing design sites provide marketing, consulting and designing in relation to the house. The web life style on cyberspace is common and makes many changes happen in house life and environment.

• Mycobiology
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• 제45권3호
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• pp.204-208
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• 2017

Nosema ceranae is an obligate intracellular fungal parasite that causes mortality in honey bees and enhances the susceptibility of honey bees to other pathogens. Efficient purification of Nosema spores from the midgut of infected honey bees is very important because Nosema is non-culturable and only seasonably available. To achieve a higher yield of spores from honey bees, in this study, we considered that the initial release of spores from the midgut tissues was the most critical step. The use of 2 mm beads along with enzymatic treatment with collagenase and trypsin enhanced the homogenization of tissues and the yield of released spores by approximately 2.95 times compared with the use of common 3 mm beads alone. The optimal time for the enzyme treatment was determined to be 1 hr as measured by the yield and viability of the spores. A one-step filtration using a filter paper with an $8-11{\mu}m$ pore size was sufficient for removing cell debris. This method may be useful to purify not only N. ceranae spores but also other Nosema spp. spores.