• 대한치과기공학회지
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• 제33권4호
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• pp.517-528
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• 2011

Purpose: In this study, we aim to provide fundamental database for the development of programs that will enhance the satisfactions of the dental technicians' daily life. To this end, we examined various factors that affect the subjects' social and emotional life satisfactions and their overall daily lives. Methods: Out of the random selection of the registered dental offices of Dental Technicians in Seoul, Gyeonggido, and Gangwon-do districts. Four hundred working dental technicians were asked to fill out the questionnaire from the 1st of June to the 25th of August, 2011. We collected the 355 sheets of the questionnaire and took frequency analysis, t-test, analysis of variance and structural equation modeling using SPSS Win 12.0 program. Results: The results of this study is as follows; Firstly, social satisfaction of the subjects turned out 3.71 on average, emotional satisfaction and daily life satisfaction in general were shown 2.77 and 3.19 respectively. Secondly, Age(p<.05), Career(p<.001), Working environment satisfaction(p<.001) showed significant differences in social life satisfaction area, whereas monthly earning(p<.05), working environment satisfaction(p<.001) revealed meaningful differences in the domain of emotional life satisfaction. Thirdly, in the overall satisfaction of daily lives, monthly earning(p<.05), career(p<.01), working environment satisfaction(p<.001) indicated significant difference. Conclusion: Seen from the results of this study, we purport to develop a variety of programs for better working conditions and to further research on the variables affecting the dental technicians' satisfaction of daily lives.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.665-666
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• 2006

In precision laser microfabrication, focusing is essential to acquire good machining precision and uniform machining quality. If it does not perform, laser machining cannot be realized. So, confocal scanning method with high depth resolution is used for focus detection technique. This paper is concerned with a procedure for design, analysis and performance test of an autofocus fine actuating stage, which is composed of flexure-hinge type lever mechanism and piezoelectric actuator. Through series of analytical design, the stage is simplified as a rigid bodies(lever and main body) and springs(flexure hinges). The simplified model was applied to determine the dimension of flexure hinges and lever. After structural analysis confirmed design requirement, an actual stage was made and verified through an experiment on the static and dynamic characteristics(maximum stroke and 1st natural frequency). The fabricated stage was satisfied with the design requirement.

• 한국소음진동공학회논문집
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• 제16권2호
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• pp.183-189
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• 2006

In mobile phones of multimedia era, microspeakers of high qualify sound are essential parts to generate human voice in speaker phone and MP3 song player. In this paper, two types of microspeakers, outer permanent magnet (PM) and combined PM type, are analyzed using electromagnetic, mechanical and their coupling analysis. For performance comparison, voice coil diameter is chosen as a design parameter to change excitation position and magnet volume for both types. For combined PM type, sound pressure level (SPL) is improved due to increased PM volume compared to outer PM type. Also, with the decreased voice coil diameter for combined PM type, the 1st resonant mode of the diaphragm is more efficiently excited due to concentrative excitation, resulting in lower and broader frequency range. Therefore, it can be said that the combined PM type microspeakers are more advantageous for high performance microspeaker which are essential for multimedia era.

• 한국소음진동공학회논문집
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• 제14권10호
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• pp.999-1006
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• 2004

Recently, the ride comfort problem becomes increasingly important because of today's needs for train speedup. The railway has the track irregularities which cause vibrations, such as rail joints, turnout, level crossing, transition corves and super-elevation ramps, and variations in the track level(z-axis) and the gauge(y-axis). In Korea, the service run of the high speed train has been made since the 1st of April, 2004. The commercial high-speed trains must be run on the compound lines which are composed of high-speed line and conventional line. The high speed lines in both Kyoungbu line and Honam line have 57.5％ and 33.8％, respectively In this Paper, the ride comfort has been reviewed by the various experimental methods when the high-speed trains are operated on both Kyoungbu line and Honam line. The results show that the high-speed train has no problems from the viewpoint of the comfort ride during the operation on the high speed line and conventional line.

• 한국임상수의학회지
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• 제5권2호
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• pp.61-71
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• 1988

This study was performed to compare the antagonistic effects of intravenous(0.125mg / kg) and subcutaneous(0.25mg /kg) administration of yohimbine on xylazine-induced immobilized(4.5mg/ kg) dog and to investigate the effectiveness of yohimbine compound(0.25mg / kg) in clinical practice. Mean arousal time(MAT), mean walk time(MWT), and time to return to normal electroencephalograms were remarkably decreased in all yohimbine-treated groups compared with the control. In electroencephalograms(A-B$\sub$I/ lead), there were no significant alteration, except RR interval. RR interval was decreased in all yohimbine-treated groups compared with the control. Second-degree heart blocks(41.7%) shown after xylazine administration disappeared within 2 min after yohimbine administration. The frequency of electroencephalograms(RO-RF trace) was recovered faster to normal in yohimbine-treated groups than that of the control. In histopathological changes of ICR mice given yohimbine compound subcutaneously, edema with inflammatory cells of hypodermis was slightly shown on the 1st day, but this findings were not observed on the 5th day. It was considered that no difference in the antagonistic effects of intravenous and subcutaneous administration of yohimbine on xylazine- induced immobilized dog were observed and yohimbine compound was usable in clinical practice for antagonistic agent to the xylazine.

• 말소리와 음성과학
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• 제7권2호
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• pp.29-38
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• 2015

This study explores reading fluency among elementary school students considering language level and family income(low SES). Forty eight students from 1st to 3rd grades participated in two paragraph reading tasks. Half of the children were from low income family and half of the children had low lexical knowledge. Reading fluency as in the number of correctly read syllables per minute, the total error frequency and error types were used to compare group differences. There were significant differences in the number of correctly read syllables per minute between two income groups and two language groups. There was a significant difference between low income group and non-low income group in total number of errors only when children's lexical knowledge were low. There were no group differences in error types of repetition and omission. Substitution and insertion error seemed to reflect the total error pattern. These results imply the importance of early screening and early involvement for children with low lexical knowledge from low income family. Monitoring and early intervention will support these children's reading development.

• 한국전자파학회논문지
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• 제13권10호
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• pp.998-1004
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• 2002

본 논문은 하나의 파일롯 신호를 이용하여 다중 캐리어를 수용하는 IMT-2000 전 대역에서 동작하는 중계기용 Feedforward 선형증폭기의 설계 및 제작에 관한 것이다. 본 논문에서 제시한 방법은 기존에 나와있는 파일롯 신호 인가 방법과는 달리 하나의 파일롯 신호를 분기하여 첫번째 루프(혼변조 신호 추출 루프)와 두번째 루프(혼변조 신호 제거 루프)에 인가함으로써, 증폭기에 입력되는 입력신호의 주파수와 레벨의 변화에 따라 자동 적응적으로 혼변조 신호들을 제거하도록 설계하였다. 제작 결과 2110 MHz - 2170 MHz 주파수 범위에서 최종 출력이 20 W$_{avg}$ 일 때 임의의 20 MHz에서 IMD 특성이 -60 dBc 이하가 됨으로써 20 dB 이상을 개선시켰으며 제안된 선형증폭기는 중계기의 다중캐리어 선형증폭기로서 적합함을 확인하였다.

• Korean Journal of Acupuncture
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• 제22권3호
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• pp.175-197
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• 2005

Objective : The purpose of this study is to review the acupuncture therapy and moxibustion on itching Method : We searched and reviewed chinese journals of and books of the acupuncture therapy and moxibustion on itching. Results & Conclusions : 1. Dermatopathy of itching is described as eczema, neurotic-dermititis, itching in orient medical text. 2. According to text, itching causes were wind symptom produced by deficiency of blood, deficiency syndrom of the spleen, and damp-heat. 3. Frequently used acupoints were LI10(41 frequency), SP10(29), ST36(27), SP6(22), GB20(19), Asi point(18), BL(17), back Su acupoints(13), LI4(13), SP9(10), PC6(7), HT7(7). etc 4. The practice of acupuncture was used by body acupuncture, auriculo-theraphy, loss of bleeding with needle, blum-blosson needle, dermal needle, fire needle. etc. 5. Moxibustions are mild moxibustion, non-scar producing moxibustion, herb- moxibustion. etc.

• 대한한방부인과학회지
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• 제18권4호
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• pp.144-152
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• 2005

Purpose : The purpose of this study is to identify the clinical effects of acupuncture and herbal medication in the treatment of primary dysmenorrhea during five or seven days before menstruation. Methods : This study was carried out to the 17 female students in kyungwon university without pelvic or other systemic disease and its history. We investigated general and menstrual characteristics through questionnaires and treated sample patients with crossover acupuncture treatment(Sojangjeonggyeok & $SP_6$) and herbal medication(Hyunburikyungtang-gagam) during five or seven days before menstruation two times. And the change of pain was measured by the method of VAS after menstration monthly two times. Results : The improvement frequency of pain after treatment according to VAS all got better after one, two months of treatment. Especially, the mean${\pm}$S.E. of VAS score after 2nd month treatment was decreased significantly compared with that of 1st month treatment(p<0.05). And Between acupuncture treatment and herbal medication groups had no significant differences on the efficacy of treatment. Conclusion : The acupuncture treatment or herbal medication during five or seven days before menstruation will be efficacious against primary dysmenorrhea.

• Journal of Advanced Marine Engineering and Technology
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• 제20권4호
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• pp.50-58
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• 1996

The torsional vibration of the propulsion shafting system equipped with viscous damper is investigated. The equivalent system is modeled by a two mass softening system with Duffing's oscillator and the vibratory motion is described by non-linear differential equations of second order. The damper casing is fixed at the front-end of crankshaft and the damper's inertia ring floats in viscous silicon fluid inside of the camper casing. The excitation frenquency is proportional to the rotational speed of engine. The steady state response of the equivalent system is analyzed by the computer and for this analyzing, the harmonic balance method is adopted as a non-linear vibration analysis technique. Frequency response curves are obtained for 1st order resonance only. Jump phenomena are explained. The discriminant for the solutions of the steady state response is derived. Both theoretical and measured results of the propulsion shafting system are compared with and evaluated. As a result of comparisions with both data, it was confirmed that Duffing's oscillator can be used in the modeling of the propulsion shafting system attached with viscous damper with non-linear stiffness.