• Journal of the Society of Naval Architects of Korea
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• v.41 no.4
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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.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.10 no.6
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• pp.587-593
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• 2017

In this paper, we propose a method to solve the difficulties in constructing an environment capable of practical training on the theoretical contents of robot control field. We make a two-wheeled mobile robot with Segway structure using LEGO block. In order to demonstrate the validity of using the developed robot as a practical application of advanced control theory of robotics education such as dynamic system and nonlinear system, the robot takes a stable posture while balancing the change of gravity during running. The results of the experiment are shown. By presenting the results, the robots made using the LEGO block are used for practical training of advanced control theory of robotics. It can be used as a tool.

• PNF and Movement
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• v.17 no.2
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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.

• Journal of the Korean Institute of Educational Facilities
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• v.13 no.3
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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.

• The Journal of Korean Institute for Practical Engineering Education
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• v.1 no.1
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• pp.38-43
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• 2009

In the study of differential equation the most obstacle is that you have to spend lots of times and the plots of solutions are not easy by hand. If we do not solve these kinds of problem, it is difficult to achieve the goal of the object which is the understanding and the practical use of the differential equation. In this paper we explain what should be Maple's usefulness in the method of removing these obstacles, and introduce the stepwise executing codes of Maple which is developed for student's easy application.

• Journal of the Ergonomics Society of Korea
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• v.5 no.2
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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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• v.30 no.1
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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.

• Journal of Institute of Control, Robotics and Systems
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• v.9 no.11
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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.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2002.03a
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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.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.28 no.2
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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.