• 전자공학회논문지
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• 제52권2호
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• pp.7-17
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• 2015

본 논문에서는 터보 등화기를 결합한 단일 안테나 구조의 동일 대역 동시 전 이중 통신 시스템을 제안한다. 본 논문에서 제안하는 시스템은 단일 안테나를 사용하기 위하여 Balanced Feed Network회로를 이용하여 송신 신호와 수신 신호를 격리시킨다. 또한 추가적으로 자기 간섭 신호를 감쇄시키기 위하여 RF Cancellation과 Digital Cancellation을 사용한다. 마지막으로 상대국에서 자국으로의 채널 상황이 열악할 경우와 Digital Cancellation이후에도 남은 잔류 자기 간섭 신호에 의한 상대국에서 보낸 수신 신호에 오류가 발생할 경우에도 통신의 신뢰도를 보장할 수 있도록 터보 등화기를 결합한다. 본 논문에서 제안하는 시스템의 성능을 확인하기 위하여 Simulink 시뮬레이션 프로그램을 이용하여 시스템을 설계하였다. 시뮬레이션 결과, 본 논문에서 제안하는 시스템은 단일 안테나를 사용하며 동일 대역에서 Balanced Feed Network, RF(radio frequency) Cancellation, Digital Cancellation 그리고 터보 등화기를 통해 자기 간섭 신호를 효과적으로 제거하고 열악한 채널 상황에서도 전 이중통신을 할 수 있다.

• 전자공학회논문지SC
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• 제47권3호
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• pp.1-4
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• 2010

다수의 노드(node)를 갖는 네트워크 시스템에 있어서 Ethernet 등의 방식을 이용한 LAN 기반의 시스템이 아닌 작은 규모의 제품에서는 RS-485 통신방식을 적용하는 것이 보통이다. 다수의 제품이 RS-485 버스에 결속되어 있을 때 각각의 제품(노드)은 Dip-Switch를 이용하여 개별 Address를 설정 한 후 전체 시스템은 소정의 작동을 하게 된다. 통신의 안정성 때문에 1:n Polling 방식을 사용 할 수 있으나 속도 문제와 Master Node의 부담으로 인하여 다자간 n:n Multi 통신방식을 선호한다. 이 경우 Master 없이 각 Node는 상대 Node의 Address로 직접 송신하게 되는데, 여기서 충돌을 막기 위하여 몇 가지 방법을 사용하긴 하지만 결국 충돌 발생률을 낮출 뿐이지 충돌은 존재 한다. 따라서 재송신 방법에 따라 시스템의 안정성이 좌우 된다. 이는 적정 지연 후 재송신 하는 것인데 이때의 지연시간 결정이 매우 모호하다. 대부분의 경우 유사 난수를 발생하여 이를 해결하곤 하는데 마이콤 기반의 작은 시스템에서의 난수 발생은 의외로 어려운 과제이므로 이 모든 것을 해결하는 방안으로 카오스난수 발생기를 마이콤에서 구현하고자 한다. 카오스 난수를 발생시키면 난수의 안정적인 결과를 기대 할 수 있으며 카오스 난수 지연으로 인하여 시스템의 안정성도 높아진다.

• 한국해양공학회지
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• 제29권4호
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• pp.317-321
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• 2015

Many kinds of generation systems have been developed to use ocean energy. Among these, with the use of an oscillating water column (OWC) for power generation is attracting attention. The OWC-type wave power generation system converts wave energy into electricity by operating a generator turbine with the oscillating water level in a column of water. There are two ways to convert wave power into electricity using an OWC. One uses a cross-flow turbine using the water level inside the OWC. The other method uses the flow of air in a Wells turbine, which depends on the water level. An experiment was carried out using a 2-D wave tank in order to minimize the number of empirical tests. The design factors were taken from Koo et al. (2012) and the experimental environment assumed by free surface motion. This paper deals with characteristics of two types of wave energy conversion systems combine with a breakwater. One model uses an air-driven Wells turbine and a cross-flow water turbine. The other type uses a cross-flow water turbine. Wave energy converters with OWCs have mostly been studied using air-driven Wells turbines. The efficiency of the cross-flow turbine was about 15% higher than that of the other model, and the water level of the OWC internal chamber for the cross-flow water turbine and air-driven Wells turbine was less than about 40% lower than the one using only the cross-flow water turbine.

• Journal of the Korean Data and Information Science Society
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• 제24권6호
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• pp.1141-1148
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• 2013

가정용수의 용도별 사용량은 주거형태, 거주자 생활양식, 주택구조 등의 내부적인 요인과 온도, 날씨, 수도요금 등과 같은 외부요인들의 영향을 받게 된다. 장기적으로는 거주민의 생활양식, 주거형태, 수도관련 시설의 변화에 따라 사용량이 점진적으로 변화하게 되며, 단기적으로는 기온이나 가뭄과 같은 기후조건이나 절수정책과 같은 인위적인 영향에 의해 사용량이 크게 변화하기도 한다. 본 연구에서는 가정에서 사용하고 있는 변기 및 세탁기 용수의 물 사용량 특성을 파악하기 위하여 전국을 대상으로 실측자료를 모니터링하고 각 사용량의 기준이 되는 원단위 (${\ell}pcd$; liter per capita day)를 도출하였으며 향후 가정용수 사용량 예측을 위하여 변기 및 세탁기 용수를 대상으로 오차항이 자기상관을 따르는 시계열 회귀모형을 이용하였다. 분석결과, 자기회귀오차 모형으로 변기 및 세탁기 용수의 사용량을 71% 정도 설명할 수 있다.

• 보건행정학회지
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• 제26권4호
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• pp.305-314
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• 2016

Background: The purpose of this study is to examine the characteristics of and factors associated with long-term care (LTC) utilization under public long-term care insurance (LTCI) among end-of-life older adults in Korea. Methods: Using a 5% sample of older people aged 65 or older and their health and LTC insurance data, two-part model analyses were conducted. We compared LTC uses and their determinants during the last year of life among decedents in the year 2010 with those of survivors. We also compared the medical uses of the same sample with their LTC uses. Results: The end-of-life elderly were more likely to use LTC, and their expenditure on LTC was higher than their counterparts. Whether or not older people used LTC during their last year of life was significantly affected by age, sex, health insurance, household income, and living alone; however, LTC costs of the decedents were only affected by functional status, which may have been due to the reimbursement scheme of the current LTCI, which is mainly based on functional dependency level. For the survivors, having chronic diseases significantly increased the likelihood of LTC use, which was not the case for the decedents. End-of-life elderly with relatively low social economic status were more likely to use the LTC other than medical services, while the health conditions affected their medical uses most significantly. Conclusion: The study findings provide key information for predicting demand related to the increasing LTC needs of Korean older people at the end of life.

• 인문언어
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• 제5권
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• pp.75-92
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• 2003

One of the distinctive features of Korean language is that it has a fine hierarchical regimentation of language uses, perhaps finer than English, Chinese or Japanese. If English language uses have a hierarchical structure they are to be thick. You may respond to any of your male colleagues often by saying either "Yes, Sir" or "Yes, John". But Korean speakers attend to the One grades of differences of social positions of a speaker and a hearer and they show the respect of the difference by adding or dropping relevant suffixes of verbs which Korean language has developed. For example, one yew difference would affect how you choose a suffix of verbs you use to speak to your hearer and two year difference often leads to the adoption of still another fitting suffix of the same verb. One year criterion works not only in 3my barracks, school dormitories but also in government offices. business sectors. Korean speaking people have been taught to use this finely regimented hierarchical language. I try, in this paper, to develop the idea that hierarchical regimentation of Korean language uses is not humane. 1 of for the main argument for the thesis as what follows: How could one justify the hierarchical regimentation of a language like Korean\ulcorner Only if there is an essential structure in which the fine grades of differences of social positions of all the people are distinct; The essentialism here involved is not plausible. And I may add that language is to be used fur the purposes of communication, rationalization and expression. If true, language use is a genuine art of liberation or humanization. Any overt hierarchical language tends to damage those purposes and more to enforce those oppressive elements already existing in the community. Then, a hierarchical language is to defeat its own purpose.

• 한국언론정보학보
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• 제40권
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• pp.45-79
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• 2007

본 연구는 이용과 충족 접근을 통해 동영상 UCC의 이용 행태와 이용 동기를 파악하기 위해 수행되었다. 요인분석을 실시한 결과 '자기표현', '사생활 영유', '참여', '정보추구', '휴식', '오락'의 총 6개 요인이 도출되었으며, 이들 중 '자기표현'의 요인의 설명력이 높게 나타났다. 동영상 UCC 이용 후 만족도를 요인 분석한 결과 역시 '자기표현', '휴식', '정보추구', '사회의식', '오락'의 총 5개 요인이 추출되었다. 추출된 이용 동기의 요인 항목 중에서는 오락과 휴식 요인의 평균값이 높게 나타남을 알 수 있었다. 동영상 UCC의 이용 행태에 따른 만족도를 살펴보기 위하여 동영상 UCC 이용 시간과 동영상 UCC 제작 경험 여부를 변인으로 하여 추출된 각 만족 요인의 평균값을 비교하였다. 동영상 UCC의 이용 시간에 따른 만족도는 '자기표현', '휴식', '정보추구' 요인에서 유의미한 차이가 나타났다. '자기표현' 요인의 경우 전반적으로 동영상 UCC의 이용 시간이 증가할수록 만족도 역시 증가하는 경향을 보였으나 2시간 이상 동영상 UCC를 이용하는 경우 오히려 만족도가 줄어드는 것을 볼 수 있었다. 마찬가지로 '휴식'과 '정보추구' 요인에서도 동영상 UCC의 이용 시간이 증가함에 따라 만족도 역시 증가하는 경향을 보였다.

• 한국물환경학회지
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• 제24권5호
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• pp.543-549
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• 2008

Human activities and land-use practices are intensely widening the urban areas. High impervious surface areas cover much of urban landscapes and are the primary pollutant sources which can lead to water quality and habitat degradation in its watershed. As the urban areas expand, transportation land-use such as parking lots, roads, service areas, toll-gates in highways and bridges also increase. These land-uses are significant in urban pollution due to high imperviousness rate and vehicular activities. To regulate the environmental impacts and to improve the water quality of rivers and lakes, the Ministry of Environment (MOE) in Korea developed the Total Pollution Load Management System (TPLMS) program. The main objective is to lead the watershed for a low impact development. On a local scale, some urban land surfaces can be emitting more pollution than others. Consequently, in urban areas, the unit loads are commonly employed to estimate total pollutant loadings emitted from various land-uses including residential, commercial, industrial, transportation, open lands such as parks and golf courses, and other developed land like parking areas as a result of development. In this research, unit pollutant loads derived specifically from transportation land-uses (i.e. branched out from urban areas) will be provided. Monitoring was conducted over 56 storm events at nine monitoring locations during three years. Results for the unit pollutant loads of transportation land-use are determined to be $399.5kg/km^2-day$ for TSS, $12.3kg/km^2-day$ for TN and $2.46kg/km^2-day$ for TP. The values are higher than those of urban areas in Korean MOE and US highways. These results can be used by MOE to separate the pollutant unit load of transportation landuses from urban areas.

• 약학회지
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• 제58권2호
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• pp.112-124
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• 2014

This study aimed to develop a regulation system for off-label drug use to secure the safe use of marketed drugs. We searched governmental documents for national and global regulating systems of off-label drug uses and a body of academic literature to explore current regulating trends. We included European Union, United Kingdom, United States of America, Australia and Japan, and critically reviewed the regulation of off-label drug use in four issues, which were a regulatory structure, safety control before and after off-label use, and information management. The findings of the present investigation called for several measures in off-label drug uses: enhancing prescribers' self-regulation, providing up-to-date information to prescribers for evidence-based practice and to patients for their informed consent, making evidence with scientific rigor, building an official registering process for off-label use in good quality and extending the role of pharmaceutical industry in pharmacovigilance. At last, we proposed a new system so as to regulate and evaluate off-label drug uses both at national and institutional level. In the new system, we suggested a clear-cut definition for clinical evidence that applicants would submit. We newly introduced an official 'Off-Label Drug Use Report' to evaluate the safety and clinical efficacy of a given off-label drug use. In addition, we developed an algorism of the regulation of off-label drug use within an institution to help set up the culture of evidence-based practices in off-label drug uses.

• 한국태양에너지학회 논문집
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• 제25권4호
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• pp.37-44
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• 2005

An experimental study was conducted to analyze performance of a heating system with variation of control logic of the system. The system uses a solar as heat source and composed with heat pump that uses R-22 as working fluid. The difference between the developed system and the commercially available heating system is working fluid. The solar assisted heating system which was widely distributed in the market uses water as a working fluid. It could be freezing in case of the temperature drops down under freezing point. The anti-freezing fluids such as methyl-alcohol or ethylene-glycol are mixed with the water to protect the freezing phenomena. However, the system developed in this study uses a refrigerant as a working fluid. It makes the system to run under zero degree temperature conditions. Another difference of the developed system compare with commercial available one is auxiliary heating method. The developed system has removed an auxiliary electric heater that has been used in conventional solar assisted heating system. Instead of the auxiliary electric heater, an air source heat exchanger which generally used as an evaporator of a heat pump was adapted as a backup heating device of the developed system. As results, an efficiency of the developed system is higher than a solar assisted heat pump with auxiliary electric heater. The merit of the developed system is on the performance increment when the system operates at a lower solar energy climate conditions. In case of the developed system operates at a normal condition, COP of the solar collector driven heat pump is higher than the air source heat exchanger driven heat pump's.