• 대한조선학회논문집
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• 제41권4호
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• pp.77-84
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• 2004

Active control is regarded as one of the most efficient and economic countermeasures to reduce excessive vibration of ship superstructure. However, it is difficult to find its practical application in real ships in spite that many studies on such systems have been done. In this study, for the practical use of an active control system to reduce ship superstructure vibration, we have developed an active vibration compensator consisting of a mechanical actuator having compact size and expected lifetime over 20 years, its control panel including exclusive signal processing and computing board, sensors to detect phase and vibration, and its operation software providing various user-interface functions. From the performance verification test of the system at a 5,500 TEU container carrier, we have confirmed the system could reduce ship superstructure vibration of a harmonic component of main engine rotating frequency up to 0.1 mm/s.

• 한국정보전자통신기술학회논문지
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• 제10권6호
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• pp.587-593
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• 2017

본 논문에서는 로봇제어분야의 이론적인 내용에 대해서 실제 실습교육이 가능한 환경을 구축하는데 따른 애로를 해결하기 위한 하나의 방안을 제시하기 위해서 세그웨이 구조의 양바퀴 이동로봇을 레고(LEGO) 블록을 사용하여 제작하고, 제작된 로봇이 로봇공학 교육의 동적시스템이나 비선형 시스템과 같은 고급제어 이론기술을 적용하는 실습용으로 활용하는 것에 대한 타당성을 제시하기 위하여 로봇이 주행 중에 중력의 변화에 대해서도 균형을 유지하면서 안정된 자세를 취하도록 하는 자세제어에 대한 실험을 수행하고 그 결과를 제시하였다. 로봇의 자세제어 주행 실험은 평면과 경사로에서 각각 수행하였으며, 평면 주행실험에서는 장애물을 인식하고 회피하는 실험을 병행하여 그 결과도 함께 제시함으로써 로봇공학의 고급제어 이론의 실습교육용으로 레고(LEGO) 블록을 이용해서 제작한 로봇이 효과적인 실습도구로 활용될 수 있음을 확인하였다.

• PNF and Movement
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• 제17권2호
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• pp.223-236
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• 2019

Purpose: This research was to develop a module for problem-based learning(PBL) and to enhance the problem-solving abilities of physical therapy students in a neurological physical therapy course and to evaluate the effects of the module using quantitative and qualitative data. Methods: The PBL module was applied to 55 third-year physical therapy students who participated in a neurological physical therapy course at S university in Seoul. Anonymous self-report questionnaires and reflection journals were collected, and the data were analyzed. Results: The results of the analysis showed that the academic achievements of the students who participated in the first PBL class improved compared to the academic achievements of the students who had participated in the same class in the previous semester. Second, the students who participated in the PBL class evaluated the PBL as a very effective learning method for developing clinical practical ability. Third, the students of the PBL class showed increased cooperation and communication abilities between team members. Conclusion: The results of this study indicated that, if PBL class case studies and various types of teaching and learning methods appropriate for theoretical and practical fields are continuously studied, then it is expected that teaching models will be developed that can develop flexibility and creativity among preliminary physical therapists in a rapidly changing medical environment.

• 교육시설
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• 제13권3호
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• pp.37-47
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• 2006

The conservation or practical use of a lot of closed schools which occurred from 1982 all over the country by governmental policy has been becoming important concerns to local resident and community with economical and administrative interest. A lot of examples, sold or rented to public institutions or a person, which have been using by welfare facilities for inhabitants, facilities for education, youth, company, culture and art, and other use, could be found. It could be said that the process of user's participation of these examples is very high, that is, a lot of examples of our surrounding is applied with ecological concept have participated by most users and local residents directly to architectural repair and renewal process, and practical use. In this background, I choose total five examples more than one by Chungbuk, Chungnam, Jeonbuk, Jeonnam district to investigate examples of closed schools applied ecological architectural concept and I researched reconfiguration of site, change of exterior or interior material, application of ecological system, and role as local community.

• 한국실천공학교육학회논문지
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• 제1권1호
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• pp.38-43
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• 2009

미분방정식의 학습에서 최대의 장애요소는 "풀이에 많은 시간이 소요된다는 점"과 "미분방정식의 해를 수작업으로 시각화하기 어렵다는 점"이다. 이러한 장애요소를 해결하지 않는다면, 교과목의 목표인 "미분방정식의 이해와 활용"을 달성하기 곤란하다. 본 연구에서는 이러한 장애요소를 제거하기 위한 방편으로 Maple의 활용에 대한 당위성을 설명하고, 또한 Maple을 보다 쉽게 사용할 수 있도록 개발된 단계별 Maple 실행코드를 소개한다.

• 대한인간공학회지
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• 제5권2호
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• pp.3-9
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• 1986

The present paper deals with obtaining the proper application criteria for the control mode, by using computer graphic simulation, in order to recover the error effectively occurring in the practical supervisory contol work of hyman-robot system. In these experiments the opteations by human and by control program are performed as control modes for recovering the error. And then we compare and analyze tow control modes taking task error and task time as performance measures and task difficulty as a variable factor. Consequently as the task difficulty increases, the task error in the operation by hyman tends to be less than in the operation by control program and the task time is superior in the operation by control program. Therefore, we suggest that two control modes should be used jointly for recovering the error and the operation by control program should be applied in major fraction of control and the operation by human in minor fraction of control.

• ETRI Journal
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• 제30권1호
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• pp.81-88
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• 2008

The security threat posed by worms has steadily increased in recent years. This paper discusses the application of the optimal and sub-optimal Internet worm control via Pontryagin's maximum principle. To this end, a control variable representing the optimal treatment strategy for infectious hosts is introduced into the two-factor worm model. The numerical optimal control laws are implemented by the multiple shooting method and the sub-optimal solution is computed using genetic algorithms. Simulation results demonstrate the effectiveness of the proposed optimal and sub-optimal strategies. It also provides a theoretical interpretation of the practical experience that the maximum implementation of treatment in the early stage is critically important in controlling outbreaks of Internet worms. Furthermore, our results show that the proposed sub-optimal control can lead to performance close to the optimal control, but with much simpler strategies for long periods of time in practical use.

• 제어로봇시스템학회논문지
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• 제9권11호
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• pp.963-968
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• 2003

A feedback control implementation for a high speed train pressurization system is proposed based on CAN (Controller Area Network). Firstly, system model including network latencies by CAN arbitration mechanisms is proposed, and an analytical compensation method of control parameters based on the system model is proposed for the network latencies. For the practical implementation of the control, global synchronization is adopted for controller to measure network latencies and to utilize them for the compensation of the control parameters. Simulation results are shown with practical tunnel data response. The proposed method is evaluated to be the most effective for the system through the control performances comparing among a controller not considering network latencies, other two off-line compensation methods, and the proposed method.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2002년도 춘계 학술발표회 논문집
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• pp.135-142
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• 2002

This paper introduces the technologies related to seismic resistance assessment of nuclear power plant structures by seismic fragility analysis(SFA). The inelastic energy absorption factor is considered in SFA to represent the effects due to the nonlinear behavior of structures and has a significant effect on the seismic fragility that is a probability of failure of structures by earthquake. Several practical methods to evaluate the inelastic energy absorption capacity of structures are investigated. The capacities determined by those methods are compared with each other. And an improved method that uses the inelastic demand capacity diagram is presented. Conclusively, some comments on each method for practical application are made.

• 산업경영시스템학회지
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• 제28권2호
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• pp.60-68
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• 2005

ISO 9000 quality standards families were established in 1987 and have been started to implement Korean industry since early 1990s. ISO 9000 standards families of 1987 were revised in 1994 and 2000, respectively, by request of world wide certification bodies and industry quality experts. This article reviews the necessity of ISO 9001 :2000 revision, quality management principles behind it, and benefits that ISO 9001: 2000 could bring. We summarize responses of foreign industry that ISO 9001: 2000 has been implemented. Survey questionnaire for 23 requirements of ISO 9001: 2000 from manufacturing companies of Busan and Kyungnam provinces are collected. Research hypotheses that there is any difference in quality management system practical application due to company size and implementation motivation are tested using SPSS. Finally, recommendations are provided for operating successful quality management system.