• JSTS:Journal of Semiconductor Technology and Science
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• 제9권1호
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• pp.29-36
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• 2009

Power supply noise is fundamentally caused by large current peaks. Since large current peaks are induced by simultaneous switching of many circuit elements, power supply noise can be minimized by deliberate clock scheduling which utilizes nonzero clock skew. In this paper, nonzero skew clock scheduling is used to avoid the large peak current and consequently reduce power supply noise. While previous approaches require extra characterization efforts to acquire current waveform of a circuit, we approximate it only with existing cell library information to be easily adapted to conventional design flow. A simulated annealing based algorithm is performed, and the peak current values are estimated for feasible clock schedules found by the algorithm. The clock schedule with the minimum peak current is selected for a solution. Experimental results on ISCAS89 benchmark circuits show that the proposed method can effectively reduce the peak current.

• Bulletin of the Korean Chemical Society
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• 제29권7호
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• pp.1386-1390
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• 2008

Artemisinin, the effective ingredient of Chinese herb Artemisia annua L (Qinghao in Chinese), has been proved to be effective to antimalarial. Herein, a reliable, sensitive and convenient electrochemical method was developed for the determination of artemisinin utilizing the excellent properties of multi-wall carbon nanotube (MWNT). The electrochemical behavior of artemisinin was investigated. It is found that the reduction peak current of artemisinin remarkably increases and the peak potential shifts positively by 240 mV at the MWNT film-modified electrode. These phenomena indicate that the MWNT film exhibits efficient catalytic activity to the electrochemical reduction of artemisinin. The effects of pH value, amount of MWNT, scan rate and accumulation time were examined. The limit of detection (S/N = 3) is as low as 10 $\mu$ g $L^{-1}$. Finally, this newly developed method was used to determine the content of artemisinin in Artemisia annua L.

• 교육시설 논문지
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• 제27권3호
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• pp.25-31
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• 2020

The reasons for studying the case of Japan are as follows. First, the increases in the aged population is similar to the case of Korea, and consumers are aging as the population ages. Second, the structure of industry in Japan is very similar to Korea, which describes the fact that the share of the manufacturing industry decreases but the service industry (e.g., medicine, finance, and insurance) increases. Third, Japan is considered as the best predictive model for forecasting the future of closed schools in Korea because the GNI gross income per capita is relatively close to the one of Korea among the several neighboring countries. The purpose of this study is to analyze the current extent of utilizing closed schools in Japan and, based on the analysis, to provide basic data on the use of closed schools in Korea in the future. The types of closed schools can be classified into education facilities, social welfare facilities, cultural facilities, public sports facilities, income growing facilities, and others. Based on the classification, the analyses of the characteristics of each type for the facilities are presented. and When the utilization status of closed schools in Japan is analyzed, 363 schools were utilized (51.4%) in 2003, means the lowest utilization rate of the target year, after that 4198 schools (70.6%) were utilized in 2015. The utilization ratio is steady increased.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2002년도 춘계 학술대회지
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• pp.28-37
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• 2002

• 콘크리트학회지
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• 제24권6호
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• pp.28-30
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• 2012

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2004년도 요약집 춘계학술발표대회
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• pp.378-378
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• 2004

• 전력전자학회:학술대회논문집
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• 전력전자학회 2006년도 전력전자학술대회 논문집
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• pp.25-27
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• 2006

This paper proposes a new full ZVS-range asymmetrical half bridge converter. It uses the variable transient current build-up technique with the load variations. The current build-up is accomplished by using the secondary synchronous switch control. Due to the blocking capacitor in secondary side, the voltage applied to leakage inductor varies with the load variations during current build-up period. Therefore, the unnecessary current build-up of leakage inductor current in heavy load condition is prevented and more current build-up in medium and light load condition is achieved for ZVS operation. That is, the variant current build-up with the load variation is accomplished for the ZVS operation. Furthermore, the DC offset of the transformer magnetizing current is also eliminated and the utilization of magnetic core is maximized.

• 디지털융복합연구
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• 제18권9호
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• pp.39-47
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• 2020

본 연구는 교육청 공무원들의 데이터 활용 실태와 빅데이터 활용에 대한 인식을 조사하여 광역시·도교육청 차원에서의 빅데이터 활용을 위한 시사점을 도출하고자 하였다. 이를 위하여 A도교육청 공무원 440명을 대상으로 온라인 설문을 진행하였다. 조사결과 교육청 공무원들이 업무에 활용하는 데이터 유형과 출처는 다양하였으며, 데이터 활용에 있어 데이터 수집 및 정제가 가장 어려운 부분으로 인식하고 있었다. 그러나 데이터 활용을 위한 소속 교육청의 인프라는 부족한 실정으로, 빅데이터 인프라 구축이 가장 필요한 요소인 것으로 나타났다. 빅데이터에 대한 지식수준은 낮지만 빅데이터 활용의 관심과 필요성을 높게 인식하고 있었다. 빅데이터 활용 목적은 현재의 교육 문제점과 해결 대안, 미래 예측에 대한 전망과 해결, 교육 수요자들의 요구 파악 등 교육정책 의제 설정과 관련되어 있었다.

• 한국산학기술학회논문지
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• 제16권11호
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• pp.7463-7473
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• 2015

본 연구는 장기요양 1등급 건강보험가입자를 대상으로 장기요양서비스 이용자와 미이용자의 의료비 지출 차이를 비교하고, 의료비 지출에 미치는 영향 요인을 규명해 보고자 시도하였다. 연구 대상은 건강보험가입자로 2009년 1월 1일부터 12월 31일까지 1등급 판정을 받은 21,213명 전수를 대상으로 국민건강보험공단의 장기요양급여, 건강보험급여 자료를 활용하였다. 연구결과 2007년부터 2009년의 연간 총 진료비 변화량의 경우 서비스 이용자에 비해 미이용자는 5,337천원 증가하였으며, 연간 요양병원 진료비 변화량은 5,449천원 증가하였다. 연간 총 입원일 변화량의 경우 서비스 이용자에 비해 미이용자는 87.31일 증가하였으며, 요양병원 입원일 변화량은 79.47일 증가한 것으로 나타났다. 이 같은 결과는 장기요양 서비스 미이용자의 의료이용, 특히 요양병원의 의료이용이 높게 나타남에 따라 미이용자에 대한 적정의료와 요양서비스 지원 정책을 통해 장기요양과 의료서비스의 효율적 연계가 필요로 된다.

• 한국축산식품학회지
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• 제41권2호
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• pp.224-236
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• 2021

The objective of this study was to investigate the effects of quality grade (QG) on the physicochemical composition and eating quality attributes of pork belly and shoulder butt. Seventy-two growing-finishing crossbred pigs were slaughtered and their carcasses were graded according to the Korean pork carcass grading system. Based on the grading criteria, the carcasses were classified into: QG 1+ (n=23), QG 1 (n=23) and QG 2 (n=26) groups. At 24 h postmortem, belly and shoulder butt cuts were collected from the QG groups and used for analysis of meat quality, flavor compounds and eating quality attributes. Results showed that the variation in fat content among QG was approximately 2% in the both cut types. The QG showed no effects on all the quality traits: cooking loss, pH and color of the belly or shoulder butt (p>0.05). Thirty-five flavor compounds comprising mainly fatty acids oxidation/degradation-derived products (e.g., aldehydes) and only few Maillard reaction-derived products (e.g., sulfur-and nitrogen-containing compounds) were identified. However, the QG showed a minor effect on the flavor profiles in both the belly and shoulder butt. Regarding the sensory quality, no effects of the QG were found on all the eating quality attributes (color, flavor, juiciness, tenderness and acceptability) for both the belly and shoulder butt cuts (p>0.05). Thus, it may be concluded that the current pork carcass grading standards do not reflect the real quality and value of the belly and shoulder butt cuts.