• 한국추진공학회지
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• 제15권1호
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• pp.19-28
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• 2011

본 연구에서는 속도 복합형 초음속 충동형 터빈의 최적 동익 오버랩을 선정하기에 앞서, 사전연구차원에서 동익 오버랩에 따른 터빈 성능특성을 분석하였다. 축대칭 노즐과 환형 노즐 대신에 사각단면 초음속 노즐이 적용된 속도 복합형 터빈에 대해 연구를 수행하였다. 상용 유동해석 프로그램을 이용한 터빈의 3차원 전산해석을 통해 익근보다는 익단에 오버랩을 적용한 경우가 터빈의 성능을 향상시키는데 더 효과적이며, 익근과 익단 모두 오버랩을 적용한 경우가 터빈의 성능 향상 가장 큰 것으로 나타났다. 2단 동익 오버랩의 경우, 전체 터빈에서 2단이 발생시키는 출력이 약 22~23%에 지나지 않으므로 2단 동익 오버랩에 의한 터빈 성능 향상은 크지 않은 것으로 파악되었다.

• 산업경영시스템학회지
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• 제39권2호
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• pp.88-102
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• 2016

This paper considers the allocation and engagement scheduling problem of interceptor missiles, and the problem was formulated by using MIP (mixed integer programming) in the previous research. The objective of the model is the maximization of total intercept altitude instead of the more conventional objective such as the minimization of surviving target value. The concept of the time window was used to model the engagement situation and a continuous time is assumed for flying times of the both missiles. The MIP formulation of the problem is very complex due to the complexity of the real problem itself. Hence, the finding of an efficient optimal solution procedure seems to be difficult. In this paper, an efficient genetic algorithm is developed by improving a general genetic algorithm. The improvement is achieved by carefully analyzing the structure of the formulation. Specifically, the new algorithm includes an enhanced repair process and a crossover operation which utilizes the idea of the PSO (particle swarm optimization). Then, the algorithm is throughly tested on 50 randomly generated engagement scenarios, and its performance is compared with that of a commercial package and a more general genetic algorithm, respectively. The results indicate that the new algorithm consistently performs better than a general genetic algorithm. Also, the new algorithm generates much better results than those by the commercial package on several test cases when the execution time of the commercial package is limited to 8,000 seconds, which is about two hours and 13 minutes. Moreover, it obtains a solution within 0.13~33.34 seconds depending on the size of scenarios.

• 한국콘텐츠학회논문지
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• 제10권7호
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• pp.81-87
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• 2010

본 논문에서는 현재 생물정보학 연구에서 가장 많이 사용하고 있는 BLAST의 문제점을 분석하고 이에 따른 해결책을 제시하기 위하여 그리드 컴퓨팅을 이용한 G-BLAST(Grid Computing을 이용한 Basic Local Alignment Search Tool)를 제안한다. 본 연구에서 제안하고 있는 G-BLAST을 이용한 시스템은 이기종 분산 환경에서 수행이 가능한 서열분석 통합 소프트웨어 패키지이며 기존 서열분석 서비스의 취약점인 검색 성능을 개선하여 BLAST 검색 기능을 강화 하였다. 또한, BLAST 결과를 사용자가 관리 및 분석이 용이하도록 데이터베이스 및 유전체 서열분석 서비스 시스템을 구현하였다. 본 논문에서는 G-BLAST시스템의 성능확인을 위하여 병렬컴퓨팅 성능테스트 기법을 도입하여 구현된 시스템을 기존 BLAST와 속도 및 효율부분에서 비교하여 성능개선을 확인하였으며 서열결과 분석에 필요한 자료를 사용자관점에서 제공해주고 있다.

• 대한한의학회지
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• 제45권1호
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• pp.203-214
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• 2024

Objectives: In the context of competency-based education emphasized in Korean Medicine, this study aimed to develop a pilot version of a CPX (Clinical Performance Examination) Practicing Chatbot utilizing large language models with prompt engineering. Methods: A standardized patient scenario was acquired from the National Institute of Korean Medicine and transformed into text format. Prompt engineering was then conducted using role prompting and few-shot prompting techniques. The GPT-4 API was employed, and a web application was created using the gradio package. An internal evaluation criterion was established for the quantitative assessment of the chatbot's performance. Results: The chatbot was implemented and evaluated based on the internal evaluation criterion. It demonstrated relatively high correctness and compliance. However, there is a need for improvement in confidentiality and naturalness. Conclusions: This study successfully piloted the CPX Practicing Chatbot, revealing the potential for developing educational models using AI technology in the field of Korean Medicine. Additionally, it identified limitations and provided insights for future developmental directions.

• 기본간호학회지
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• 제24권1호
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• pp.39-50
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• 2017

Purpose: The purpose of this study was to identify the effects simulation-based education combined team-based learning (SBE combined TBL) compared to simulation-based education (SBE) on undergraduate nursing students. Methods: A non-equivalent control group design with pre-and posttest measures was used. The participants in the study were 181 students. The SBE combined TBL group consisted of 84 senior students in 2013, and the SBE group consisted of 97 seniors in 2014. Collected data were analyzed using chi-square, independent t-test and ANCOVA with the statistical package SPSS 22.0 for Windows. Results: There was a significant improvement in communication skills, nursing performance confidence, team efficacy, and team performance scores in the SBE combined TBL group compared to the SBE group (t=2.45, p=.015; F=4.30, p=.040; t=3.06, p=.003; t=8.77, p<.001). However, there was no statistically significant difference in self-directed learning between the groups. Conclusion: SBE combined TBL compared to SBE is an effective teaching and learning method to enhance various positive educational outcomes for nursing students. Therefore, we suggest that future studies investigate the development of an integrated course in which team-based learning is applied to theoretical sessions and simulation-based training.

• 한국치위생학회지
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• 제14권5호
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• pp.695-701
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• 2014

Objectives : The purpose of this study was to investigate the relationship between the resilience and organizational commitment of dental hygienists for the improvement of organizational performance. Methods : A self-reported questionnaire was filled out by 323 dental hygienists from May 2 to June 5, 2014. The collected data were analyzed by a statistical package SPSS WIN 12.0. Results : The dental hygienists had the highest score in relationship(4.09), and had the lowest score in communicative competence(3.29). In organizational commitment, they had the highest score in affective commitment(3.20). There were statistically significant differences in that regard according to age(p<0.001), marital status(p<0.05) and career(p<0.001). The organizational commitment varied significantly with age(p<0.05) and career(p<0.01), and normative commitment significantly varied with the number of work days(p<0.05) and career(p<0.05). There was a significant correlation between the resilience and organizational commitment of the dental hygienists(p<0.001). Conclusions : The organizational commitment of the dental hygienists was better when they had a better resilience, and that resilience made a contribution to the improvement of organizational commitment in the clinical dental hygienists.

• 대한영양사협회학술지
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• 제16권3호
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• pp.208-225
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• 2010

Our research consisted of a qualitative study investigating the quality attributes of university foodservices through focus group interviews and a quantitative study evaluating service quality of university foodservices through a survey. Sixteen quality attributes were derived and customer satisfaction questionnaires included these 16 quality attributes with a five-point Likert scale. An Importance-Performance Analysis (IPA) model was applied in order to identify operational strategies necessary to improve service quality. The survey questionnaires were distributed to 600 university students enrolled in a university located in Kwangju and statistical analysis was performed on 555 surveys using an SPSS package. Overall customer satisfaction with the quality of university foodservices was relatively low (under 3.0) while the expectation was inclined to be high (over 4.0). The main reasons for using the university foodservice were given as inexpensive price (67.6%) and time saving (22.9%). A factor analysis of 16 quality attributes revealed two separate factors: food quality (Cronbach's alpha=0.911) and service quality (Cronbach's alpha=0.934). Variety of menu, convenient location, and sanitation of utensils and facilities were identified by an IPA model as factors needing improvement in operational strategies.

• 천문학회보
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• 제42권1호
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• pp.57.1-57.1
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• 2017

As an upgrade we report the current ASTE ultra-wideband corrugated horn design. The length of the feedhorn gets shortened from 12.5 mm to 11 mm, and it shows better side lobe level at the far-field patterns compared with the previous design. We looked into possible quasi-optical solution to match the feedhorn beam to the optics of the current ASTE telescope, starting from frequency-independent solution using two ellipsoidal mirrors to which wideband performance of the feedhorn naturally fits. We used a commercial physical optics package (GRASP) with an user-defined optimizer to give physical constraints to evaluated optical designs for highest efficiency.

• 대한전기학회논문지:전력기술부문A
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• 제51권7호
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• pp.327-332
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• 2002

In this paper, conventional reactive power compensation is defined and instantaneous real control concept for shunt converters is proposed. This equipment incorporates the compensation function of harmonics at the distribution line by nonlinear load. These methodologies are applied to IEEE 13 distribution system with the modeling of nonlinear load using EMTEDC/PSCAD package. Simulation with EMTDC results presented to confirm that the new approach has better performance than those obtained by controllers based on traditional concepts of reactive power compensation.

• 대한기계학회논문집A
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• 제41권2호
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• pp.111-119
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• 2017

본 논문은 자세 제어 장치(ESC)와 후륜 조향 장치(RWS)를 장착한 통합 섀시 제어기의 성능을 향상시키기 위해 후륜 조향각을 결정하는 방법을 제안한다. 차량을 안정화시키기 위해 필요한 제어 요 모멘트는 자세 제어 장치와 후륜 조향 장치를 이용하여 만들어진다. 각 장치의 타이어 힘을 결정하기 위해 의사역행렬 제어할당 방법을 적용한다. 제어기의 성능을 향상시키기 위해 후륜 조향 장치의 조향각을 결정하는 데에 네 가지 방법을 적용한다. 차량 시뮬레이션 패키지인 CarSim에서 시뮬레이션을 수행하여 제안된 방법들이 통합 섀시 제어기의 성능을 향상시킬 수 있음을 검증한다.