• Journal of Power Electronics
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• v.10 no.6
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• pp.587-594
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• 2010

The paper reports about methodology at design of interactive e-learning modules that are suitable both for teaching and learning. They cover special topics of electrical engineering, starting from the fundamentals, through electrical machines, power electronics to the fields of controlled electromechanical energy conversion, like electrical drives, complex drive systems, application of drives, mechatronic systems, telemanipulation, and robotics. In the paper, the emphasis is devoted in detail to philosophy and realization of the modules from fields of Power Electronics and Electrical Drives. On several examples there are explained main principles and specialties at their development.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.51 no.6
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• pp.321-329
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• 2002

A protection scheme for series active compensator is presented and analyzed in this paper. The proposed series active compensator operated as a high impedance K($\Omega$) to the fundamentals when short-circuit faults occur in the power distribution system, and two control strategies are proposed in this paper The first is the method by detecting the fundamental source current through the p-q theory, the second is the method by detecting the fundamental component of load current in Synchronous Reference Frame(SRF). When the short-circuit faults occur in the power distribution system, the proposed scheme can protect the series active compensator without additional protection circuits. The validity of the Proposed Protection scheme was investigated through experimental results.

• Journal of Power System Engineering
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• v.9 no.1
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• pp.5-13
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• 2005

Acoustic emission(AE) is defined as the transient elastic waves thar are generated by the rapid release of energy. The advantage of AE is that very early crack growth can be detected well before a highly stressed component may fail. At present, an exact diagnosis is the most reliable means for determining the soundness of structures during power plant operations. AE monitoring has been applied successfully in power plants to determine mechanical problems, pressure vessel integrity and external valves leaks, vacuum leaks, the onset of cavitation in pumps and valves, the presence of flow(or no flow) in piping and heat exchange equipment, etc. Acoustic emission(AE) technology has recently strengthened its application base, and practitioners' understanding of the technique's fundamentals. This paper introduces the methods of a survey and assessment on AE monitoring applications in nuclear, fossil and hydraulic power plant. The main objective of this paper was to obtain information on various applications of AE technology in power plant.

• Journal of the Korean Society for Nondestructive Testing
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• v.24 no.4
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• pp.396-409
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• 2004

Diagnosis f structural integrity is the basis for correct treatment of and countermeasures against progressive structural abnormalities. An exact diagnosis is at present the most reliable means for determining the soundness of structures during power plant operations. Acoustic emission(AE) technology has recently strengthened its application base, and practitioners' understanding of the technique's fundamentals. This paper presents the results of a survey and assessment on AE monitoring applications in nuclear, fossil and hydraulic power plant. The main objective of this paper was to obtain information on various applications of AE technology in electric power plant.

• Journal of Power Electronics
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• v.2 no.4
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• pp.250-257
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• 2002

This paper introduces the Interactive Power Electronics Seminar - iPES - a new software package for teaching of fundamentals of power electronic circuits and systems. iPES is constituted by HTML text with Java applets for interactive animation, circuit design and simulation and visualization of electromagnetic fields and thermal issues in power electronics. It does comprise an easy-to-use self-explaining graphical user interface. The software does need just a standard web-browser, i.e. no installations are required. iPES can be accessed via the World Wide Web or from a CD-ROM in a stand-alone PC by students and professionals. Due to the underlying software technology iPES is very flexible and could be used for on-line learning and could easily be integrated into an e-learning platform. The aim of this paper Is to give an introduction to the iPES-project and to show the different areas covered. The e- learning software is available at no costs at $\underline{www.ipes.ethz.ch}$ in English, German, Japanese, Korean, Chinese and Spanish. The project is still under development and the web page is updated in about 4 weeks intervals.

• Journal of Advanced Marine Engineering and Technology
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• v.28 no.2
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• pp.163-184
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• 2004

Vortex flow fundamentals have been investigating for about hundred years and many distinguished features had been discovered and comprehensively studied over that time. Due to unique hydrodynamic features vortex flows are now widely used in many industrial applications, including energy and power systems. combustion chambers. fuel sprayers. heat exchangers. clean-up systems. drying chambers. Up to recently aerospace engineers employed vortex flow only in combustion systems to stabilize a flame zone or in advanced heat exchangers to enhance heat transfer processes. This paper provides an overview of some recently developed aerothermal vortex technologies applied to aerospace engineering.

• Proceedings of the KIEE Conference
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• 1987.11a
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• pp.150-153
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• 1987

This paper describes the fundamentals, system configuration, existing situation and future prospect of the cogeneration system and valuation of its economic effects. Especially, increasing this system should be evaluated for national energy management deeply, because KEPCO has generation units eneugh which can be met demend currently and in the near future and nuclear power generation has been more than 50% of total generation.

• Transactions of The Korea Fluid Power Systems Society
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• v.5 no.4
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• pp.10-16
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• 2008

In this paper, the authors benchmark a servo valve model for the fuel supply system of Auxiliary Power Unit (APU) in the KHP helicopter. This valve is directly driven with a torque motor, and the size of small gap controlled by a flapper can make change of flow rate under given pressure drop between inlet and outlet. CFD analyses using a commercial code, ANSYS-CFX 10 are performed for the series of three-dimensional models at various openness conditions. The computational results on simplified models show that CFD can play a fine roll in the design of flow path as well as in the estimation of flow force due to its precision and good repeatability. Consequently, the CFD analysis helps valve designers to understand its flow characteristics from the basis of physical fundamentals.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.14 no.3
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• pp.270-279
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• 2007

Purpose: In this study, the effects of meridian massage and hand massage on the affected upper extremity of patients with a stroke were identified. Method: A nonequivalent control group non-synchronized design was used. Participants were 84 (Experimental. 1: 28, Experimental. 2: 28, Control.: 28) patients with a stroke who were hospitalized in K oriental medical center. Experimental treatment for patients in experimental group 1 was the meridian massage for 10 minutes daily for 2 weeks, and for those in experimental group 2, hand massage for 2 minutes, 30 seconds each, daily for 2 weeks. Outcome variables were upper extremity function (grip power, shoulder pain, edema, ROM), ADL, and depression. Data were analyzed using SPSS PC+ version. Results: The score for upper extremity functions and ADL were significantly higher in experimental group 1 who had meridian massage than for experimental group 2 or the control group. Experimental group 1 showed less depression than experimental 2 or the control group. Conclusion: Meridian massage can be an effective nursing intervention to improve upper extremity function and ADL, and to decrease depression in patients stroke who have had a stroke.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.15 no.4
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• pp.457-466
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• 2008

Purpose: The purpose of this study was to determine the effects of low intensity exercise program with telephone coaching on the physical fitness of elderly people who are receiving home visiting nursing care. Method: This study was conducted using a non-equivalent control group pretest-posttest design. The participants were 61 elders. Elders (34) in the experimental group performed low intensity exercise and of these 16 received telephone coaching. The low intensity exercise program consisted of stretching, muscle strengthening with an elastic band, massage, and ball exercise, five days a week, for sixteen weeks. Data were collected from July 2007 to December 2007. $x^2$-test, ANCOVA with SPSS WIN 11.0 program were used to analyse the data. Results: There were statistical differences in the right grasping power in the right hand (p=0.021), Raising behind of right arm (p=0.006), Raising behind of left arm (p=0.007). Conclusion: These results indicate, that a low intensity exercise program with telephone coaching can help improve physical fitness in elders receiving served home visiting nursing care.