• Journal of Electrical Engineering and Technology
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• 제13권1호
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• pp.168-180
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• 2018

In order to achieve the high quality output voltage of single-phase voltage source inverters, in this paper an Adaptive Complementary Sliding Mode Control (ACSMC) is proposed. Firstly, the dynamics model of the single-phase inverter with lumped uncertainty including parameter variations and external disturbances is derived. Then, the conventional Sliding Mode Control (SMC) and Complementary Sliding Mode Control (CSMC) are introduced separately. However, when system parameters vary or external disturbance occurs, the controlling performance such as tracking error, response speed et al. always could not satisfy the requirements based on the SMC and CSMC methods. Consequently, an ACSMC is developed. The ACSMC is composed of a CSMC term, a compensating control term and a filter parameters estimator. The compensating control term is applied to compensate for the system uncertainties, the filter parameters estimator is used for on-line LC parameter estimation by the proposed adaptive law. The adaptive law is derived using the Lyapunov theorem to guarantee the closed-loop stability. In order to decrease the control system cost, an inductor current estimator is developed. Finally, the effectiveness of the proposed controller is validated through Matlab/Simulink and experiments on a prototype single-phase inverter test bed with a TMS320LF28335 DSP. The simulation and experimental results show that compared to the conventional SMC and CSMC, the proposed ACSMC control strategy achieves more excellent performance such as fast transient response, small steady-state error, and low total harmonic distortion no matter under load step change, nonlinear load with inductor parameter variation or external disturbance.

• 산업융합연구
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• 제21권3호
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• pp.57-64
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• 2023

기술의 발전과 융복합화가 진행되면서 전유 메커니즘에 대한 기업들의 관심이 나날이 증가를 하고 있다. 이에 본 연구에서는 국내 IT기업의 전유 메커니즘 효과성에 대해 파악을 하고자 하였다. 이를 위해 선행연구 검토와 전문가를 통해 최종적으로 7개의 전유 메커니즘을 도출하고 이를 실증분석하였다. 분석결과, SW기업에서는 리드타임, 특허, 영업비밀, 보완적 판매 및 서비스, 디자인 등록, 보완적 제조, 학습곡선효과 순으로 그 중요도가 나타났다. HW 기업에서는 특허, 영업비밀, 리드타임, 디자인 등록, 보완적 판매 및 서비스, 학습곡선효과, 보완적 제조 순으로 그 중요도가 나타났다. 또한 공통적으로 특허, 영업비밀, 리드타임이 중요한 요인으로 선정이 되었다. 본 연구의 결과는 기업에서 전유 메커니즘 전략을 수립하는데 있어 유용한 가이드라인으로 활용이 가능할 것으로 보인다.

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2014년도 춘계 종합학술대회 논문집
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• pp.239-240
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• 2014

Researchers in KISTI have been participating in the WISET Fellow Mentoring program since 2009 [1]. We describe the history and future of WISET Fellow Mentoring program from KISTI. We have communicated with mentees more freely and effectively using complementary online and offline system. In addition, we designed a automated matching process in order to help mentors and mentees to begin mentoring with satisfaction [2-6]. In the future, we plan to use our automated matching process for matching candidate mentors and mentees in order to obtain more satisfaction in mentoring.

• Steel and Composite Structures
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• 제20권5호
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• pp.1043-1066
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• 2016

A new analytical solution based on a third order shear deformation theory for the problem of static analysis of cross-ply doubly-curved shells is presented. The boundary-discontinuous generalized double Fourier series method is used to solve highly coupled linear partial differential equations with the mixed type simply supported boundary conditions prescribed on the edges. The complementary boundary constraints are introduced through boundary discontinuities generated by the selected boundary conditions for the derivation of the complementary solution. The numerical accuracy of the solution is compared by studying the comparisons of deflections, stresses and moments of symmetric and anti-symmetric laminated shells with finite element results using commercially available software under uniformly distributed load. Results are in good agreement with finite element counterparts. Additional results of the symmetric and anti-symmetric laminated and sandwich shells under single point load at the center and pressure load, are presented to provide data for the unsolved boundary conditions, benchmark comparisons and verifications.

• 한국음향학회지
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• 제32권6호
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• pp.525-531
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• 2013

본 논문은 파워 상호보완 윈도우를 이용한 지연 감소 알고리즘을 IntMDCT(Integer Modified Discreate Cosine Transform)에 적용하고자 제안한다. 기존에 사용하는 변환 방식인 MDCT는 정수 입력에 대해 실수 값을 출력하므로 데이터의 확장을 야기 시킨다. 이에 정수 대 정수 변환인 IntMDCT 기술이 등장했다. 하지만 IntMDCT는 MDCT(Modified Discreate Cosine Transform)처럼 알고리즘 지연을 갖는 문제점을 가지고 있다. 지연은 실시간 통신을 목표로 하는 환경에 있어 중요한 이슈로 자리 잡고 있다. 이러한 샘플의 지연을 최소화하기 위해 제안하는 알고리즘을 적용하고 성능을 평가한 결과, IntMDCT에서 발생하는 샘플 지연이 절반으로 감소하는 것을 확인 할 수 있었다.

• 대한간호학회지
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• 제38권3호
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• pp.445-453
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• 2008

Purpose: This paper analyzed the historical origins of the Qi concept and assesses its possible contribution to the development of complementary therapy and new nursing practices. Methods: In order to clarify the Qi concept measure its theoretical/clinical potentials, this study analyzed both historical data and experimental research that adopt and apply the concept. These include modern/contemporary research measuring its effects in promoting mental and physical health. Using the method of cross-cultural comparison, this study analyzed diverse approaches to the Qi concept and sought to find common features among the approaches. Results: A historical, cross-cultural analysis revealed several fundamental similarities between Qi theories that have developed in the east and the holistic concepts that have evolved in the western traditions. Especially, the analysis of the more recent research on the Qi concept shows ample possibilities of its future contributions to the development of new diagnostic applications and the promotion of overall human health. Conclusion: The historical study of the Qi concept found some key common factors in the diverse philosophical traditions in the east and the west. Considering the growing popularity of complementary therapy among health professionals and the general public, the Qi concept and its clinical applications are expected to promote human health. In this context, this research contributes to developing new nursing practices based on the concept by clarifying its philosophical origins and theoretical backgrounds.

• 한국정보통신학회논문지
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• 제8권7호
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• pp.1453-1463
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• 2004

기존의 레벨셋을 이용한 이미지 분할 방법은 화소값의 기울기를 이용하기 때문에 지역적 형태에 좌우되는 문제점을 지니고 있다. 본 논문에서는 평활한 구동력을 위하여 레벨 셋 함수와 새로운 보상 평활화 함수를 결합시키는 하이브리드 방법을 이용한 방법이 소개된다. 대부분의 경우에 3 교점을 가지고 있지 않다는 가정하에 보상함수를 얻는 방법을 대안으로 고려하였다. 보상함수의 주요 역할은 원보상 함수와 평균 보상함수의 차가 새로운 레벨셋 함수의 합리적인 구동력으로 소개될 수 있다. 본 논문에서 제안한 하이브리드 방법은 기존 레벨셋을 이용한 방법의 단점을 최소화시키는 방법이다.

• 동서간호학연구지
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• 제21권2호
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• pp.110-118
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• 2015

Purpose: This study aimed to provide a basic resource for developing nursing interventions and educational programs for complementary and alternative therapies (CAT) by examining nursing students' perception, experience, and attitudes toward CAT. Methods: Data were collected targeting 230 nursing students from October 20 to November 10, 2014, and analyzed by using descriptive statistics, t-test, ${\chi}^2$-test, and ANOVA with SPSS/WIN 18.0. Results: Results showed that CAT were performed by CAT specialists in combination with hospital treatments for individuals suffering from chronic pain and musculoskeletal diseases. Nursing students obtained information on and experience of CAT through the Internet. CAT were used for psychological and mental stability as a supplementary treatment. The majority of the participants used Yoga followed by massage as a sub-therapy of the program. They said that openness of medical staff and active communication are important for having a positive attitudes toward CAT. There are differences in attitudes toward CAT according to gender, student levels, and previous experience on CAT. Conclusion: It is crucial for nursing students to have right perception, experience, and attitudes toward CAT in order to apply CAT to the clinical field.

• Preventive Nutrition and Food Science
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• 제18권3호
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• pp.196-202
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• 2013

Citron seed extracts (CSEs) were made using distilled water (CSEW), ethanol (CSEE), and n-hexane (CSEH), to measure the total polyphenol contents, DPPH and ABTS radical scavenging activities, and anti-complementary activity. The total polyphenol content was observed the highest in CSEE (188.71 ${\mu}g/mL$), and occurred in the following order: CSEE>CSEW (141.11 ${\mu}g/mL$)>CSEH (26.19 ${\mu}g/mL$) at 10 mg/mL. CSEE (63.56%) and CSEW (56.61%) showed significantly higher DPPH radical scavenging activities when compared with CSEH (28.57%). ABTS radical scavenging activities of CSEE (45.53%) and CSEW (40.02%) were also observed to be higher, whereas CSEH did not show ABTS radical scavenging activity. Anti-complementary activity of CSEE (26.85%) showed a greater activity than that of CSEW (7.84%) at 1,000 ${\mu}g/mL$. Limonin and nomilin contents had the highest values (1.882% and 2.089%) in CSEE, and with 0.327% and 0.139% in CSEW; however, CSEH showed relatively very low values at 0.061% and 0.026%, respectively. Among the CSEs tested, CSEE as a by-product from citron may provide an important source of dietary antioxidant compounds with rich polyphenol and limonoid contents, and immunopotentiating activity, including the complement activation factor.

• Preventive Nutrition and Food Science
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• 제17권2호
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• pp.136-140
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• 2012

Trifoliate orange seed extracts (TSEs) were made using either distilled water (TW), ethanol (TE), or n-hexane (TH), to measure total polyphenol contents, DPPH and ABTS radical scavenging activities, and anti-complementary activity. The results showed that the total polyphenol content showed higher value at TE (235.24 ${\mu}g/mL$, p<0.05) than those of TW (132.65 ${\mu}g/mL$) and TH (165.44 ${\mu}g/mL$) at 10 mg/mL and TE exerted the highest DPPH radical scavenging activity (61.77%, p<0.05), which occurred in the following order: TE TW (56.87%)>TH (39.78%). The results of ABTS radical scavenging activity showed that TW (34.26%) and TE (31.81%) showed similar activities, which were higher than TH (12.74%, p<0.05). Anti-complementary activity of TE (61% at 500 ${\mu}g/mL$) showed a higher activity when compared with the positive control (60% at 1,000 ${\mu}g/mL$) polysaccharide-K (PSK), a known immuno-active polysaccharide from Coriolus versicolor. Consequently, among TSEs, TE is a byproduct from trifoliate orange and could be an important source of dietary polyphenolic antioxidant compounds and immunopotentiating activity, including complement activation.