• The Transactions of the Korean Institute of Power Electronics
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• v.12 no.1
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• pp.89-97
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• 2007

This paper describes a load simulator with power recovery capability, which is based on the voltage source converter-inverter set. The load simulator can save the electric energy that should be consumed to test the operation and performance of the power quality compensator and the power equipment. The load simulator consists of a converter-inverter set with a DSP controller for system control and PWM pulse generation. The converter operates as a universal load to model the linear load and the non-linear load, while the inverter feed the energy back to the power source with harmonic compensation. the performance of proposed load simulator was analyzed with scaled-model experiment, interconnected with the active power filter. The experimental results confirms that the proposed load simulator can be utilized to test the performance of active power filter.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.19 no.1
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• pp.9-14
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• 2019

A small millimeter-wave tracking radar is a pulse-based radar that searches, detects, and tracks a target in real time through a TWS (Track While Scan) method for a traps target on the sea with a large RCS running at low speed. It is necessary to develop a board equipped with a high-speed CPU to acquire and track target information through LPRF, DBS, and HRR signal processing techniques for a trap target operating various kinds of dexterous objects such as chaff and decoy, We designed a signal processor structure including DFT (Discrete Fourier Transform) module design that can perform real - time FFT operation using FPGA (Field Programmable Gate Array) and verified the signal processor implemented through performance test.

• Journal of Korean Academy of Nursing
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• v.36 no.4
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• pp.630-636
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• 2006

Purpose. To determine the effects of music therapy on pain, discomfort, and depression for patients with leg fractures. Methods. Data were collected from 40 patients admitted in an orthopedic surgery care unit. The subjects included 20 intervention group members and 20 control group members. Music therapy was offered to intervention group members once a day for 3 days for 30-60 minutes per day. Pain was measured with a numeric rating scale and by measuring vital signs. Discomfort and depression were measured with self-administered questionnaires. Results. Patients who received music therapy had a lower degree of pain than patients who did not receive music therapy as measured by the numeric pain score (p < 0.001), systolic blood pressure (p < 0.01), diastolic blood pressure (p < 0.001), pulse rate (p < 0.001) and respiration (p < 0.001). Patients who were provided with music therapy also had a lower degree of discomfort than patients who were not provided with this therapy (p < 0.01). Effects of Music Therapy on Pain, Discomfort, and Depression for Patients with Leg Fractures Conclusions. These results demonstrate that music therapy is an effective method for decreasing pain and discomfort for patients with leg fractures.

• Journal of the Korean Home Economics Association
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• v.37 no.7
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• pp.83-94
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• 1999

The purpose of this study was to explore musical development of 3- to S-year-old children and their musical home environment. The subjects were one hundred ninety-four children and their mothers enrolled in four kindergartens in Seoul. Each child sang the birthday song with peers in a birthday play setting. It was audiotaped for the children to sing the song. Questionnaire of musical home environment developed by the researchers was used for the mothers. The children's rhythm and pitch development were coded by the scoring categories of Project Spectrum(Krechevsky, 1994). The data were analyzed by t-test, ANOVA, Scheffe, and Pearson correlation. The results of this study were as follows: Firstly, there was no a significant difference in the children's rhythm development among three age-groups as well as between boys and girls. Among rhythm subcategories, the unit of note was ranked in the highest score and the pulse the next. Secondly, there were significant differences in children's pitch development among three age-groups and between boys and girls. The older children significantly achieved higher scores than the younger. Among pitch subcategories, the contour was ranked in the highest score and the interval the next. Thirdly, the children's musical development and their physical home environment related to music were correlated positively. The children's pitch development was significantly related to the mothers' musical attitude and the children's rhythm development to the mothers' educational levels.

• Journal of Korean Academy of Nursing
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• v.48 no.4
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• pp.465-474
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• 2018

Purpose: This study aimed to determine the effect of hand massage in patients who underwent transradial percutaneous coronary intervention. Methods: This was a quasi-experimental study with a nonequivalent control group and non-synchronized design. The study included 30 patients in the experimental group and 30 in the control group. Hand massage was performed 2 times for 5 minutes each in the experimental group and the control group only received usual nursing interventions. Pain, level of discomfort, and vital signs were defined as key outcome measures, and the data were analyzed using the chi-square test, an independent t-test, Mann-Whitney U test, repeated-measures analysis of variance, and Friedman test. Results: Significant differences were observed between the 2 groups in the pain score (F=7.91, p=.003), discomfort score (F=18.15, p<.001), pulse (F=12.92, p<.001), and respiration rate (${\times}^2=19.35$, p<.001). Conclusion: Hand massage can be a helpful nursing intervention for transradial percutaneous coronary intervention by reducing pain and discomfort to a considerable degree.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.35 no.3
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• pp.328-334
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• 1999

A fish pump makes very important roles in an automation system of an aquaculture farm, thus it has been used widely in order to transfer fishes from one place to the other place automatically. In spite of its significant roles, the efforts for developing performance and promoting efficiency of the fish pump are not sufficient yet. In this paper, a method which makes the fish pump automation system is suggested. Automation of the fish pump can be accomplished by using variable voltage and variable frequency inverter system including induction motors. Especially, very simple logic to generate Pulse width Modulation(PWM) wave to control induction motor efficiently and three steps speed control method to regulate liquid quantity of the fish pump simply are suggested. Owing to the simplifies speed control and PWM wave generation technique, a cheaper microprocessor, 80C196KC, than a digital signal Processor(DSP) can be used to operate control algorithm in induction motor systems for real time control Also, a new idea of remote control for the simplifies novel inverter system by Programmable logic Controller(PLC) without special output unit, digital to analog converter(D/A), is suggested in this paper. Consequently the function of reliability, availability and serviceability of the fish pump system are developed. It will be expected to contribute expanding of application of the fish pump in aquaculture farms because the system can reduce energy consumption and some difficulties according to manual operation prominently.

• Journal of Korean Biological Nursing Science
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• v.13 no.2
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• pp.94-101
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• 2011

Purpose: The purpose of this study is to examine effects of Recorded Mother's Voice on weight and physiological reactions to the premature infants. Methods: This study was conducted on the nonequivalent control group pre-posttest quasi-experimental design and the subject group was the premature infants who were admitted in Neonatal Intensive Care Unit in Pusan National University Hospital. Total 50 infants, divided into two groups 25 experimental and control were participated in the study. The data were analyzed using frequency, %, chi-square test, t-test between the two groups. Results: The results of this study were as followingsfollowings; In the physical response(heart rate, respiration rate, pulse oximetry saturation), there were significant statistical difference between two groups. Conclusion: In short, it turned out that the intervention of the recorded mother's voice had some significance as nursing intervention with positive impacts. Such as improving infant's growth and stablizing their physical response. By providing the effectiveness of such intervention, the study will further provide the evidence-based information in developing the practice of pediatric nursing.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.3
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• pp.632-640
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• 2007

The low force estimation method of skeletal muscle was proposed by using ICA(independent component analysis) and neuro-transmission model. An EMG decomposition is the procedure by which the signal is classified into its constituent MUAP(motor unit action potential). The force index of electromyography was due to the generation of MUAP. To estimate low force, current analysis technique, such as RMS(root mean square) and MAV(mean absolute value), have not been shown to provide direct measures of the number and timing of motoneurons firing or their firing frequencies, but are used due to lack of other options. In this paper, the method based on ICA and chemical signal transmission mechanism from neuron to muscle was proposed. The force generation model consists of two linear, first-order low pass filters separated by a static non-linearity. The model takes a modulated IPI(inter pulse interval) as input and produces isometric force as output. Both the step and random train were applied to the neuro-transmission model. As a results, the ICA has shown remarkable enhancement by finding a hidden MAUP from the original superimposed EMG signal and estimating accurate IPI. And the proposed estimation technique shows good agreements with the low force measured comparing with RMS and MAV method to the input patterns.

• Journal of Advanced Navigation Technology
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• v.6 no.2
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• pp.97-103
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• 2002

A recent technology trends in synthetic aperture radar(SAR) requires the ultra high resolution performance in detecting and precisely identifying the targets. In this paper, as a technique for enhancing the radar range resolution, the wide band chirp connection algorithm is presented by stitching the several chirp modules with unit bandwidth based on the linear frequency modulated chirp signal waveform. The principles of the digital chirp signal generation and its architecture for implementation is described with the wide band chirp signal generator, modulator, and demodulator. The performance analysis for the presented algorithm is given with the simulation results.

• Proceedings of the KIEE Conference
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• 2000.07a
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• pp.357-359
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• 2000

This paper is to introduce the R&D project called "Improvement of Automatic Gene-ration Control Related Systems for New Energy Management system". The principal objective of this project is to demonstrate AGC operation capabilities that are suitable to new EMS environment and to show the validity of Set-Point Control Method. A number of developments and enhancements have been made to the generator's Remote Terminal Unit in which new ASTC is being developed and installed. The so-called ACC Signal Transfer Card(ASTC) will include RTU's Set-Point Control capabilities. It is expected that over next few months both RTU & DCS software modifications will be given and a relatively new Set-Point Control Method will be chosen instead of those from more conventional method, pulse control method.