• 조명전기설비학회논문지
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• 제28권1호
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• pp.57-68
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• 2014

This paper propose a development of squirrel-cage induction motor(IM) for 5-phase 1.5kW, 220V, 60Hz in order to study a polyphase ac machinery that keep hold of advantages more than traditional three-phase a IM, such as reducing a amplitude of torque pulsation, decreasing electric noises, and increasing the reliability. Designed methods of the motor use a development tools with Maxwell 2D and Simplorer program. There are designed drawing of manufactured frames of the IM. amplitude and waveform of the generated electromotive force, FFT analysis of harmonics within output voltages and current, and reviewing a experiment results are shown by variable output. We are presenting a design and manufacture methods for the 5-phase squirrel-cage IM.

• Journal of Power Electronics
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• 제19권3호
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• pp.714-726
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• 2019

This paper proposes a hybrid-boost Modular Multilevel Converter (MMC) for the Medium-Voltage (MV) Variable Speed Drives (VSDs) employed in subsea applications, such as oil and gas recovery. In the presented architecture, a hybrid-boost MMC with a reduced number of semiconductor devices driving a multiphase Induction Machine (IM) is investigated. The stepped output voltage generated by the MMC reduces or eliminates the filtering requirements. Moreover, the boosting capability of the proposed architecture eliminates the need for bulky low-frequency transformers at the converter output terminals. A detailed illustration of the hybrid-boost MMC operation, the expected limitations/constraints, and the voltage balancing technique are presented. A simulation model of the proposed MV hybrid-boost MMC-based five-phase IM drive has been built to investigate the system performance. Finally, a downscaled prototype has been constructed for experimental verification.

• 조명전기설비학회논문지
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• 제28권5호
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• pp.52-59
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• 2014

This paper presents an improved operating characteristics of squirrel-cage induction motor(IM) for 5-phase 1.5kW, 220V, 60Hz in order to study a polyphase AC machinery that keep hold of advantages more than traditional three-phase a IM, such as reducing a amplitude of torque pulsation, decreasing electric noises, and increasing the reliability. The developed manufacturing motor was necessary to do improvement of speed regulation, efficiency, operating characteristics, and so on at rated load. There are remake a redesigned and distributed stator winding connection without changing the frames of stator and rotor core in previous established the motor by a repeat tests. There are shown a experiments results of no-load test, locked rotor test, operating characteristics at variable load, FFT analysis of harmonics within output voltages and current waveform, decided motor parameters.

• 동의생리병리학회지
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• 제25권2호
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• pp.359-364
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• 2011

The purpose of this research is to propose the range of five phases which need to be essentially included in the introductory course of Korean medicine, its significance and the relationship with applied subjects. The students in School of Korean Medicine participated in a survey to figure out the response rate and status of the five phases described in the textbooks. In the preparatory survey, 43 items in the phases were selected; in the main one, there were differences only in the response rate to respective items, not in the grade level. In addition, the survey for the present condition of the textbooks was conducted with six categories to see if there is description of the five phases. Based on the two results, the importance of 43 five phases items was classified into low, medium, and high levels. It is expected that the efficiency of education can be increased if 14 items included in high significance and 11 in medium, which are classified according to the findings of this study, must be instructed in the introductory course of Korean medicine, and if 18 items in low significance are used as reference materials.

• 한국전문물리치료학회지
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• 제25권2호
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• pp.44-52
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• 2018

Background: The deep cervical flexor (DCF) muscles have a crucial role in the management of neck pain. For preventing neck pain by activation of the DCF, craniocervical flexion (CCF) is an effective exercise. However, sternocleidomastoid (SCM) muscle is considered to affect negatively the activation of the DCF. SCM muscle which is an accessory muscle for respiration is activated differently depending on types of breathing patterns. It's not certain that breathing patterns affect the SCM and DCF muscles thickness during CCF exercise. Objects: The purpose of this study was to investigate the influence of breathing patterns on the SCM and DCF muscles thickness during CCF exercise. Methods: Forty-five subjects participated in this study, and they were classified according to their breathing pattern, as follows: costodiaphragmatic breathing (CDB) and upper costal breathing (UCB) groups. Ultrasonographic imaging of the SCM and DCF muscles was performed during five incremental levels of CCF during tidal breathing and expiration. Results: There was a significant interaction between the breathing pattern and the phase of CCF for percentage of SCM muscle thickness changes (p<.05). In phase 1 CCF, a percentage of SCM muscle thickness changes was increased in the UCB group than in the CDB group (p<.05). There was an increase in DCF muscles thickness with each additional CCF phase (p<.05). Conclusion: Recruitment of SCM muscle was increased in the UCB group while performing CCF with a low intensity. There were no significant differences on DCF recruitment between the breathing pattern groups. Higher CCF exercise intensities elicited a higher DCF recruitment.

• 문화기술의 융합
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• 제9권6호
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• pp.813-825
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• 2023

본 연구는 혼종 모형 방식을 사용하여 정신 간호사의 공감적 의사소통역량에 대한 개념을 명확히 하기 위해 분석되었다. 이론적 단계에서 2000년부터 2022년까지 출판된 문헌을 수집하여 최종 38편의 논문을 분석하였다. 현장 작업단계를 위하여 2022년 12월 1일부터 12월 28일까지 8명의 정신 간호사를 대상으로 심층 면담을 진행하였다. 최종 분석 단계를 통해 정신 간호사의 공감적 의사소통역량의 차원과 속성을 도출하여 개념을 분석하였다. 이론적 단계와 현장 작업단계에서 파악된 속성을 바탕으로 정신 간호사의 공감적 의사소통역량을 정의하면 5개의 차원과 12개의 속성으로 종합되었다. 이에 따라서 정신 간호사의 공감적 의사소통역량은 정신 간호사가 대상자에 대한 공감과 이해를 바탕으로 효과적인 의사소통을 위해 적극적 경청과 공감적 스킬을 사용하고, 대상자의 생각과 감정에 민감하게 반응하여 대상자가 표현하고자 하는 바를 정확하게 전달하고 대상자를 존중하며 대상자에게 힘을 실어주는 기술과 능력을 의미한다.

• Journal of Electrical Engineering and Technology
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• 제10권2호
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• pp.574-585
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• 2015

This paper aims to improve the performance of conventional direct torque control (DTC) drives proposed by Takahashi by extending the idea for 5-level inverter. Hybrid cascaded H-bridge topology is used to achieve inverter voltage vector composed of 5-level of voltage. Although DTC is very popular for its simplicity but it suffers from some disadvantages like- high torque ripple and uncontrollable switching frequency. To compensate these shortcomings conventional DTC strategy is modified for five levels voltage source inverter (VSI). Multilevel hysteresis controller for both flux and torque is used. Optimal voltage vector selection from precise lookup table utilizing 12 sector, 9 torque level and 4 flux level is proposed to improve DTC performance. These voltage references are produced utilizing a hybrid cascaded H-bridge multilevel inverter, where inverter each phase can be realized using multiple dc source. Fuel cells, car batteries or ultra-capacitor are normally the choice of required dc source. Simulation results shows that the DTC drive performance is considerably improved in terms of lower torque and flux ripple and less THD. These have been experimentally evaluated and compared with the basic DTC developed by Takahashi.

• 한국환경농학회지
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• 제29권2호
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• pp.165-175
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• 2010

A gas chromatographic (GC) method was developed to determine residues of captan, folpet, captafol, and chlorothalonil, known as broad-spectrum protective fungicides for the official purpose. All the fungicide residues were extracted with acetone containing 3% phosphoric acid from representative samples of five agricultural products which comprised rice, soybean, apple, pepper, and cabbage. The extract was diluted with saline, and dichloromethane partition was followed to recover the fungicides from the aqueous phase. Florisil column chromatography was additionally employed for final cleanup of the extracts. The analytes were then determined by gas chromatography using a DB-1 capillary column with electron capture detection. Reproducibility in quantitation was largely enhanced by minimization of adsorption or thermal degradation of analytes during GLC analysis. Mean recoveries generated from each crop sample fortified at two levels in triplicate ranged from 89.0~113.7%. Relative standard deviations (RSD) were all less than 10%, irrespective sample types and fortification levels. As no interference was found in any samples, limit of quantitation (LOQ) was estimated to be 0.008 mg/kg for the analytes except showing higher sensitivity of 0.002 mg/kg for chlorothalonil. GC/Mass spectrometric method using selected-ion monitoring technique was also provided to confirm the suspected residues. The proposed method was reproducible and sensitive enough to determine the residues of captan, folpet, captafol, and chlorothalonil in agricultural commodities for routine analysis.

• Composites Research
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• 제26권5호
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• pp.322-327
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• 2013

탄소섬유강화 SiC기지상 복합재는 우수한 산화저항성과 우수한 열충격저항성을 가진다. 그리고 이런 특성들은 탄소섬유강화복합재가 고온구조재로서 응용케하였다. 본 연구에서는 $C_f/SiC$ 복합재가 전구체 함침과 액상 함침이 동반된 열분해공정, Cyclohexene을 사용한 화학기상 경화공정을 통해 제조되었다. 최종 제조된 $C_f/SiC$ 복합재는 5회 함침을 통해 $0.43g/cm^3$ 밀도를 갖는 탄소섬유 프리폼에서 $1.76g/cm^3$의 밀도값을 나타내고 있다. 그리고 산화저항성 특성면에서 $C_f/SiC$ 복합재의 무게가 공기중 $1400^{\circ}C$에서 6시간 유지 후에 81%가 남았다. 결과적으로 Cyclohexene을 사용한 화학기상 경화공정은 효과적으로 높은 치밀화와 증가된 산화저항성을 보이고 있다.

• 동의생리병리학회지
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• 제26권6호
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• pp.855-863
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• 2012

The organic and holistic recognition method about nature in east asian philosophy is also applied to the study of the human body in Korean medicine. In Korean medicine, the human body is being understood from a holistic point of view rather than a mechanical or reductive one. The main east asian philosophies are the heavens thought and the Yin-yang/Five Phase Theory. This study will explore the influence the general flow of heavens thought has on explaining the human body in Korean medicine and the formation of how the human body is perceived in "Huangdineijing"(黃帝內經). First, the primitive meaning of heaven was developed to include the natural heaven of Xia (夏), the lord heaven of Shang(商) and the moral heaven of Zhou(周) dynasties. Among these, the natural heaven notion of the Xia(夏) dynasty which recognized heaven as the one with the power to create everything. This was followed by Taoism which established the contrasting system of heaven and earth. Based on this, "Huangdineijing"(黃帝 內經) developed the perception of the human body, taking into account, heaven as the original substance to generate the human body through the mutual sympathy between heavenly energy and earthly form. The perspective of the correspondence between nature and human in "Huainantzu"(淮南子) and "L$\breve{u}$shichunqiu"(呂氏春秋) was succeeded by Tung Chung-Shu(董仲舒). Based on this development, the perception of the human body in "Huangdineijing"(黃帝內經) is related to the seasonal cycle and the notion of night and day to balance the physiology of the human body. It recognizes that its structure, shape, emotional state and physiological actions are correlated with heaven.