• 한국통신학회논문지
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• 제42권1호
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• pp.268-278
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• 2017

본 논문에서는 동시 무선 정보 및 전력 전송 시스템에서 전송률-에너지 영역 관점에서의 근본적인 트레이드오프를 최소화하기 위해 제안되었던 새로운 수신기 구조를 기반으로 복잡도가 낮은 새로운 검출 기법들을 제안한다. 첫 번째로 에너지 하베스팅을 위한 정류된 신호로부터 얻을 수 있는 진폭 정보를 통해 유클리드 거리 기반으로 부호의 진폭을 먼저 검출한 후 기존의 정보 복호화 과정에서 얻을 수 있는 위상 정보를 통해 유클리드 거리를 기반으로 최종 부호를 검출하는 이단 검출 기법을 제안한다. 두 번째로 기존의 정보 복호화 과정을 통해 얻을 수 있는 진폭과 위상 정보를 포함한 유클리드 거리와 에너지 하베스팅을 위한 정류된 신호로부터 얻을 수 있는 진폭정보를 포함한 유클리드 거리를 결합하여 부호를 검출 할 수 있는 유클리드 거리 결합 검출 기법을 제시한다. 모의실험을 통해 부호 에러율과 부호 성공률-에너지 영역, 달성 가능한 전송률-에너지 영역 측면에서 기존의 정보 복호화 기법보다 우수한 성능을 얻음을 확인하였다.

• 한국의류학회지
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• 제15권2호
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• pp.211-227
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• 1991

The purpose of this study was to investigate the effects of design modification, decoration and color scheme of traditional Korean women's clothing on impression formation by 2 age groups of women. The instruments developed for the study were 2 sets of stimuli and a response scale. Stimuli I (design stimuli) consisted of 6 line drawings of female figures in Korean clothing and modified Korean style clothing, whereas stimuli II (color stimuli) consisted of 6 colored drawings of female figures in different color schemes. The 7-point semantic differential scale of 14 bipolar adjectives were used for the response scales. 144 female college students and 144 middle·aged women subjects were randomly assigned to one of 6 drawings from each set of stimuli. The data were analyzed by factor analysis, ANOVA and t-test. 1) There factors emerged to account for dimensions of design and color scheme, respectively. The first factor was interpreted as Evaluation/prestige both in design (stimuli I) and color scheme (stimuli II), the second factor was Modernity for stimuli I, and the third factor for stimuli I was Practicality. On the other hand, the Luxuriousness/Individuality was factor 2 and Modernity was factor 3 for stimuli ll. 2) Modification had the largest effect on impressions regarding design and decorated designs had a partial effect on the impression of Modernity and Practicality. The female figures in modified Korean style clothing were perceived as more prestigious, modern and practical than those in traditional Korean clothing. 3) Color schemes had little effect on impressions, while perceiver's age had a larger effect. Middle·aged women formed more positive impressions toward Korean clothing of various color schemes than female college students.

• 대한전기학회논문지:전력기술부문A
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• 제54권9호
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• pp.427-433
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• 2005

In DC tracking power supply system, ground faults are currently detected by the potential relay, 64P. Though 64P relay detects ground fault, it cannot Identify the faulted region which causes long traffic delays and safety problem to passengers. Two new ground fault protective relay schemes that can identify the faulted region are presented in this paper. One is bus differential protective relay and the other is ground overcurrent protective relay. Both type of relays is similar in principle to the ordinary bus differential protective relay and the ground overcurrent relay used in other power system. In DC traction power supply system, since it is ungrounded, ground fault current is not big enough to operate those relays. To solve the problem, a current control device, called device 'X', is newly introduced in both system, which enables large amount of ground fault current flow upon the positive line to ground fault. Algorithms for these relays are developed and their validity are verified by EMTP simulation.

• The Journal of Asian Finance, Economics and Business
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• 제8권4호
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• pp.193-200
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• 2021

This study investigates the impact of managerial ability and managerial incentives on firm performance. In particular, it studies how managerial ability factor can exert significant influence on the profitability and the risk of firms. By doing this, the study can provide several policy implications about how managerial ability can influence firm decisions and its corresponding business policies. Data of the study was collected from the Annual Enterprises Survey (AES), which is conducted by the General Statistics Office of Vietnam (GSO) during the 2009-2013 period. After removing firms with insufficient financial information, our final dataset includes over 50,000 firms in Vietnam. The main result of the study shows that there is a significant and positive relationship between managerial ability and firm leverage. This finding indicates that managerial ability significantly plays an important role in making financial decisions. In addition, our study provides empirical evidence about the causal relationship between managerial compensation and firm risk-taking behavior. Specifically, we find that firm risks are significantly associated with compensation schemes including lower delta and higher vega. In other words, our study implies that the sensitivity of CEO wealth to stock volatility can positively affect both delta and vega or managerial incentives schemes.

• Journal of Electrical Engineering and Technology
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• 제8권3호
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• pp.499-506
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• 2013

The accurate estimation of a fault location is desired in distance protection schemes for transmission lines in order to selectively deactivate a faulted line. However, a typical method to estimate a fault location by calculating impedances with voltages and currents at relaying points may have errors due to various factors such as the mutual impedances of lines, fault impedances, or effects of parallel circuits. The proposed algorithm in this paper begins by extracting the fundamental phasor of the positive sequence currents from the three phase currents. The second-order difference of the phasor is then calculated based on the fundamental phasor of positive sequence currents. The traveling times of the waves generated by a fault are derived from the second-order difference of the phasor. Finally, the distance from the relaying point to the fault is estimated using the traveling times. To analyze the performance of the algorithm, a power system with EHV(Extra High Voltage) untransposed double-circuit transmission lines is modeled and simulated under various fault conditions, such as several fault types, fault locations, and fault inception angles. The results of the simulations show that the proposed algorithm has the capability to estimate the fault locations with high speed and accuracy.

• 한국산학기술학회논문지
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• 제17권7호
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• pp.92-102
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• 2016

본 연구는 국내 외 가설기자재 관련 제도 및 기준 등을 비교 분석하여 가설기자재 안전인증제도 개선방안을 제시하며 건설 산업에서 사용 중인 가설기자재의 안전성을 확보하고자 한다. 현재 사용되는 가설기자재 안전인증제도 이행실태를 파악하기 위하여 생산 임대 사용의 가설기자재 관련 종사자에 대해 인터넷 설문조사 및 현장방문 인터뷰를 실시하여 통계분석을 수행하고 안전인증제도 실태조사 및 개선방안을 제시하였다. 안전인증제도는 2009년부터 시행되고 있지만 한국산업안전보건공단의 '건설중대재해 사례와 대책'을 확인하면 건설재해는 매년 증가하는 추세이다. 가설기자재 관련 종사자의 안전인증품목 적절성에 대한 응답은 '예(36%)', '아니오(30%)', '잘 모르겠음(35%)'으로 현행 안전인증제도 적합성에 대한 긍정적인 응답률이 절반에도 미치지 못하는 것을 알 수 있다. 현재의 가설기자재 안전인증제도는 건설 환경의 변화를 따라가지 못하고 있다는 의견이 많았다. 또한 국외 가설기자재 및 신소재 신제품에 대한 인증 방안 모색과 재사용가설기자재 자율등록제 제도 보완 및 안전성 증대 방안이 필요할 것으로 나타난다. 본 연구를 통하여 현행 안전인증제도의 인증대상 품목, 인증규격의 현실 적합성 및 인증방법 등을 검토한 후 안전인증제도 개선방향을 제시 하였다.

• Asian Pacific Journal of Cancer Prevention
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• 제16권14호
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• pp.6055-6059
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• 2015

Background: Medication policy development in Thailand is continually promoting rational drug use. Letrozole, an endocrine therapy drug, is usually prescribed for post-menopausal status early and advanced stage breast cancer. After Ministry of Public Health announced Letrozole as compulsory licensed drug in 2009, more breast cancer patients can access to this drug at low cost especially those within universal coverage schemes. To ensure that Letrozole is rationally prescribed, the drug utilization study was conducted. Objectives: The aim of this study was to describe the appropriate use of Letrozole in breast cancer and the relationship between appropriate use and health benefit schemes. Materials and Methods: A retrospective study to evaluate use of Letrozole in breast cancer patients was performed for six months between January - June 2010 in seven regional cancer hospitals, Thailand. All prescriptions of Letrozole were identified from pharmacy dispensing databases and prescription papers. A medical record review was also performed to evaluate appropriate use referring to the drug use evaluation criteria. The approved criterion of this study was referred from the guideline of Thai National Formulary version 2010. Results: There were 681 prescriptions of Letrozole for 254 breast cancer patients with an average age of $58.6{\pm}10.0years$. The patients in universal coverage scheme (UCS), civil servant medication benefit scheme (CSMBS) and social security scheme (SSS) were 77.7%, 18.5% and 8.7% respectively. 10.6% were prescribed Letrozole for the first time. Letrozole were prescribed by oncologists (82.8%). The average number of tablets per prescription was $58{\pm}10$. Calcium supplements were prescribed concomitant with Letrozole for 19.4%. To assess drug use evaluation criteria, 45 prescriptions were excluded because of uncompleted clinical data, 636 prescriptions were evaluated. The study showed 86 prescriptions (13.5%) with inappropriate use including 6 (0.9%) not prescribed for estrogen receptor (ER) and/or progesterone receptor (PR) positive, 31 (4.9%) not prescribed for post-menopausal and 49 (7.7%) not prescribed for an appropriate duration. Appropriate use percentages in different health benefit schemes were similar, 85.7% of CSMBS, 86.4% of SSS and 86.7% of UCS. The relationship between health benefit scheme and appropriate use of Letrozole was not significantly different, ${\chi}^2$ (2, N = 636) = 0.081, p > 0.05. Conclusions: The study showed inappropriate use in breast cancer patients because of non-compliance with duration, menopausal status and hormone receptor requirements. To prescribe appropriate indication did not referred to the appropriate practice along the treatment. Drug use evaluation proved very useful for detecting the sign of inappropriate use and allows immediate feedback to the stakeholder for developing medication policy in the future. Importantly, there was no significantly difference in appropriate use of Letrozole across health benefit schemes.

• 한국사회정책
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• 제25권4호
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• pp.265-299
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• 2018

2015년부터 보건복지부는 지역자활센터 법인 형태를 사회적협동조합으로 전환하여 지역자활센터의 자활근로사업 위주 사업에 다양성 및 자율성을 부여하고, 자활사업 대상자 확대 및 근로빈곤층의 일자리 창출에 기여하고자 지역자활센터 유형다변화 시범사업을 시작하였다. 본 연구는 지역자활센터 유형다변화 사업이 점차 확대되는 상황에서 지역자활센터의 사회적협동조합의 전환과정과 변화 분석을 통해 긍정적인 요소를 강화하고 부정적인 요소는 제거하는데 도움이 되는 정책적 제언을 하고자 하였다. 분석 결과, 지역자활센터가 시범사업 참여, 즉 사회적협동조합으로의 전환은 지역자활센터의 주도적인 변화라기보다 조직의 지속 가능성을 모색하는 하나의 선택이었다. 그리고 이사회와 조합원 구성에서 생산자나 소비자의 참여는 저조하였고, 사회적협동조합으로의 전환은 종사자의 적극성과 책임성의 증가라는 긍정적 효과를 보였다. 또한 사회적협동조합 지역자활센터에 대한 운영비 활용의 자율성 확대로 매출 증가를 위한 적극적인 영업 활동과 전문성 제고의 결과를 낳았다. 사회적협동조합 설립 후 지역자활센터의 가장 큰 변화는 지역사회 내에서 자활사업의 인지도 향상과 지역사회 협력의 증가였다. 지역사회 네트워크를 통해서 지역자활센터가 새로운 사업에 참여하고 지자체의 우선 지원사업 대상이 되는 기회가 확대되었다. 그렇지만 사회적경제 조직이 활성화되지 않은 지역에서는 큰 변화가 없는 한계도 있었다. 지역자활센터의 사회적협동조합으로의 전환은 긍정적인 요소도 있지만 자활사업 참여자의 감소와 근로능력이 저하되는 상황을 고려한 유형다변화 사업의 방향과 내용 설계에 대한 고민이 필요하다.

• Structural Engineering and Mechanics
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• 제73권3호
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• pp.353-365
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• 2020

In the previous studies, the authors proposed the use of laminated veneer lumber - carbon fiber reinforced polymer (LVL-CFRP) composite beams for structural application. Bond strength of the LVL-to-CFRP interface and flexural strengthening schemes to increase the bending capacity subjected to positive and negative moment were discussed in the previous works. In this article, theoretical models are proposed to predict the moment capacity when the LVL-CFRP beams are subjected to negative moment. Two common failure modes - CFRP fracture and debonding of CFRP are considered. The non-linear model proposed for positive moment is modified for negative moment to determine the section moment capacity. For the debonding based failure, previously developed bond strength model for CFRP-to-LVL interface is implemented. The theoretical models are validated against the experimental results and then use to determine the moment-rotation behaviour and rotational rigidity to compare the efficacy of various strengthening techniques. It is found that combined use of bi- and uni-directional CFRP U-wrap at the joint performs well in terms of both moment capacity and rotational rigidity.

• 응용통계연구
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• 제22권6호
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• pp.1289-1300
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• 2009

표본추출 비용의 절감을 위해 흔히 사용되는 이중표본추출방법은 대부분의 표본들이 2종류의 오류에 의해 오염이 되어 있어 통계적 분석이 상대적으로 용이하지 않다. 특히, 비율의 추론을 위한 중요한 분석 도구인 구간추정은 현재까지 우도추정량의 정규근사에 의존하는 Wald 방법만이 알려져 있으나 Wald 신뢰구간은 포함확률의 근사성 등에서 많은 문제가 있다는 것이 여러 연구에서 확인되고 있다. 본 연구에서는 이중표본추출에서 Wald 신뢰구간의 문제점을 파악하고 이에 대한 대안으로 Agresti-Coull 유형의 신뢰구간을 제시한다.