• Structural Engineering and Mechanics
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• 제89권6호
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• pp.549-556
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• 2024

A serial pendulum dynamic vibration absorber (DVA) was designed to suppress the vibration of two degrees of freedom (Two-DOF) structure model. The optimal DVA parameters are selected using a genetic algorithm (GA) by minimizing the fitness function formulated from the system's frequency response function (FRF). Two fitness function criteria, using one and two target frequency ranges, were utilized to calculate the optimal DVA parameters. The optimized serial pendulum DVA parameters were used to reduce structural vibration under free and forced excitation conditions. The simulation study found that the serial pendulum DVA can effectively reduce the vibration response for a small excitation amplitude. However, the DVA performance decreases for a large excitation amplitude due to the nonlinearity of pendulum motion, and the percentage of vibration response attenuation is smaller than that obtained using a small excitation amplitude.

• 물과 미래
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• 제18권4호
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• pp.317-325
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• 1985

본 연구에서는 낙동강, 한강 및 금강의 중요관측지점의 월평균 유출량을 분석에 사용하였으며, 먼저 일정유량(Truncation level) 별로 Run-length와 Run-sum에 대한 2-변수 Gamma 분포 및 대수정규분포의 적합성 여부를 검토하였던 바 Gamma 모델이 적합한 것으로 판명된 자료와 실측치와 비교하였다. 그리고 Run-length 및 Run-sum에 대한 일정유량별로 평균치의 변화에 대한 성질을 구명하였다.

• 간호행정학회지
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• 제15권4호
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• pp.593-600
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• 2009

Purpose: This study was to examine the relation of nurses' job stress and knowledge, attitude and care behavior for elderly patient in hospitals. Method: One hundred ninety one nurses caring the elderly patients in hospitals in Ilsan, Busan and Gyeongsangnam-do were subjects. The data was collected between Sept. 21 and 31, 2009. Data was analyzed using t-test, ANOVA, Pearson correlation with SPSS/Win 17.0 and the fitness of pathway models with AMOS 5.0. Results: The mean scores of job stress and knowledge were in middle range, and attitude and care behavior were in a little higher range. The fitness of hypothetical model was excellent. Job stress had direct effects on attitude and care behavior, knowledge had direct effect on attitude and attitude had direct effect on care behavior. But the pathways related to job stress and attitude and job stress and care behavior were not significant. In modified model deleted the pathway between job stress and attitude, the pathway related to job stress and behavior also was not significant. Conclusion: Education related to the elderly for nurses to improve care behavior is needed continuously.

• 한국지능시스템학회논문지
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• 제21권4호
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• pp.442-448
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• 2011

이동 로봇의 위치인식 기술을 위하여 SLAM(Simultaneous Localization and Mapping)에 관한 많은 연구가 진행되고 있다. 본 논문에서는 시야각이 넓은 어안렌즈를 장착한 단일 카메라를 사용하여 천장의 특징점을 이용한 자기위치 인식에 관한 방안을 제시한다. 여기서는 어안렌즈 기반의 비전 시스템이 가지는 왜곡 영상의 보정, SIFT(Scale Invariant Feature Transform) 기반의 강인한 특징점을 추출하여 이전 영상과 이동한 영상과의 정합을 통해 최적화된 영역 함수를 도출하는 과정, 그리고 기하학적 적합모델 설계 등을 제시한다. 제안한 방법을 실험실 환경 및 복도 환경에 적용하여 그 유용성을 확인한다.

• 간호행정학회지
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• 제19권3호
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• pp.361-371
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• 2013

Purpose: This study was done to investigate the factors affecting organizational commitment and turnover intention of hospital nurses. Empirical analysis on the mediating effect of the person-environment fit of organizational commitment and turnover intention and factors affecting this relationship were also examined. Methods: Participants were nurses working in 4 university hospitals in Seoul or Busan. Data were collected between July 27 and Aug. 10, 2012 and for the final analysis, 393 data sets were used. The fitness of models were tested using AMOS 19.0. Results: The fitness of the modified model showed high compatibility with the empirical data. In the modified model, organizational climate, professional self-concepts and person-organization fit were found to have significant effects on hospital nurses' organizational commitment. Professional self-concepts, personality, person-organization fit and person-job fit significantly affected hospital nurses' turnover intention. There was the mediating effect of person-organization fit between organizational commitment and turnover intention and factors affecting the relationship. But person-job fit was not found to have a mediating effect. Organizational commitment accounted for 49.8% and turnover intention for 39.9% of covariance in these factors. Conclusion: Nursing strategy for enhancing professional self-concepts and person-organizational fit should be planned by nursing managers.

• 한국의상디자인학회지
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• 제9권3호
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• pp.35-46
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• 2007

The purpose of this study was to modify a Flared Skirt for women according to the somatotype of lower body. The subjects for the wear test were 3 students, who were in mean${\pm}1{\sigma}$ each somatotype. As seen in the study, it was found out that there was a difference in three dimensional shape of the lower part of the body even in the group of whom the body heights, measured by Martin's system, are alike. Due to such a difference in the three dimensional shape of the lower part of the body, it was found out to be a difference in drapability of the flare skirts. In order to have better fitness of the lower part of the body and to raise the visual effect, therefore, it is suggested that there need to develop a new model of the flare skirts considering three dimensional shape of the lower part of the body for the wearer or to take complementary measures for each body shape in case of applying traditional model.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제15권2호
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• pp.442-460
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• 2021

Nowadays, recommendation systems (RSs) are applied to all aspects of online life. In order to overcome the problem that individuals who do not meet the constraints need to be regenerated when the many-objective evolutionary algorithm (MaOEA) solves the hybrid recommendation model, this paper proposes a many-objective particle swarm optimization algorithm based on multiple criteria (MaPSO-MC). A generation-based fitness evaluation strategy with diversity enhancement (GBFE-DE) and ISDE⁺ are coupled to comprehensively evaluate individual performance. At the same time, according to the characteristics of the model, the regional optimization has an impact on the individual update, and a many-objective evolutionary strategy based on bacterial foraging (MaBF) is used to improve the algorithm search speed. Experimental results prove that this algorithm has excellent convergence and diversity, and can produce accurate, diverse, novel and high coverage recommendations when solving recommendation models.

• 한국군사과학기술학회지
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• 제24권4호
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• pp.401-407
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• 2021

To confirm the change of muzzle velocity and the most suitable probability distribution model of the 155 mm K9 howitzer barrel with chrome plating and changed rifling. Using a statistical program, the muzzle velocity were plotted on a normal distribution, a 2-parameter and 3-parameter Weibull distribution on a probability paper. Also, statistical parameters were estimated and muzzle velocity fitness test and probability of K676 charge were plotted. In both the chrome-plated with standard rifling and changed rifling for K9 barrel, the 2-parameter and 3-parameter Weibull distribution were skewed to the left compared to the normal distribution. It was confirmed that the muzzle velocity of the K9 barrel with chromium-plated is suitable for the normal distribution and 3-parameter Weibull distribution model.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.93.1-93
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• 2001

An evolutionary approach for the design of Fuzzy Logic Systems(FLSs) is proposed. Membership functions(MFs) in Takagi-Sugeno type fuzzy logic system is optimized through evolutionary process. Output singleton values are obtained through pseudo-inverse method. The proposed technique is unique for that, to prevent overfilling phenomenon, limited-level RBF membership functions are used and the new fitness function is invented. To show the effectiveness of the proposed method, some simulations results on model identification are given.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 추계학술대회 논문집
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• pp.425-430
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• 2002

An automatic transmission model using the bond graph techniques is developed for analyzing shift characteristics of vehicles. Bond graph models can be systemically manipulated to yield state space equations of standard form. Bond graph techniques are applied for modeling overall automatic transmission systems and shift models. A fuzzy controller is synthesized for the verification of a shifting model in the ${1^st} gear to the {2^nd}$ gear. Simulation results show the fitness of models by the bond graph techniques.