전력전자 PSPICE 컴퓨터 시뮬레이션을 위한 스위치 모델

元忠淵,金淵俊,金世燦,金德憲 成均館大學校 科學技術硏究所 1990 論文集 Vol.41 No.2

PSPICE is widely used in analysis of general circuit and simulation in electric and electrical field is applied to power electronics circuit. The circuits used with thyristors will add significant complexity to PSPICE analysis, it is important that the thyristor model be as simple as possible. In order to solve this problem, an ideal voltage controlled switch and an ideal current controlled switch were added as circuit elements. Two typical power electronics circuits simulation using PSPICE program presented.

전류제어형 PWM 인버어터―유도전동기 위치제어의 신경회로망 응용

元忠淵,梁承浩,金世燦,金德憲 成均館大學校 科學技術硏究所 1991 論文集 Vol.42 No.1

이 논문은 전력변환기 시스템 모델링에 대한 신경회로망 사용을 기술하였다. Bp 알고리즘은 PWM 인버어터에 의해 구동되는 유도전동기의 on-off 패턴제어를 모델화하기 위해 처음으로 사용되었다. 신경회로망의 한 잇점은 본질적으로 병렬처리 이어서 그 결과 직렬인 디지털 컴퓨터보다 훨씬 빠르다. 게다가 신경회로망은 인버어터에 대해 학습능력이 있다. 제안된 방법의 타당성을 디지털 컴퓨터 시뮬레이션을 통하여 확인하였다. This paper discribes the use of neural networks for modeling power converter system. A back propagation(BP) algorithm is used firstly to model on-off pattern control of PWM inverter fed induction motor and, as a result, can solve problems much faster than a serial digital computer. Furthermore, neural networks have ability to learn for inverter. The validity of proposed method is confirm through the digital computer simulation.

초퍼제어-직류전동기의 PSPICE 컴퓨터 시뮬레이션

元忠淵,梁承浩,金德憲,金世燦 成均館大學校 科學技術硏究所 1992 論文集 Vol.42 No.2

In this paper, the authors describe the equivalent circuit for a DC motor in consideration of both magnetic saturation and armature reaction phenomena. To develop DC motor model in PSPICE is to eliminate the gap between drive electronics and models of driven machine. On the basis of these results the dynamic characteristics of a MOSFET chopper controlled DC series motor are investigated by PSPICE simulation and experiment.

신경회로망을 이용한 정현파 밴드 히스테리시스 전류 제어기

元忠淵,梁承浩,金世燦,金學成 成均館大學校 科學技術硏究所 1993 論文集 Vol.44 No.1

Current-controlled PWM inverter offers substantial advantages in improving motor system dynamics in high-performance ac drive systems under vector control. Among the various current control techniques, fixed band hysteresis current control has been widely used. A hysteresis controller employing sinusoidal bands has been reported in recent years. In this paper new current control schemes based on neural network for PWM inverter are described, Four types of controllers have been studied and their performance compared with each other. Finally, relevant simulation results are shown to prove the effectivness of the proposed current control scheme.

규조토로부터 β-Sialon의 합성

배원태,전병세,최태현,문종수 慶南大學校 附設 工業技術硏究所 1989 硏究論文集 Vol.7 No.-

카올린에 비하여 Al₂O₃의 함량이 낮은 규조토로부터 β-Sialon을 합성하였다. 불순물의 함량을 저하시키고, 반응을 증대시키기 위하여 규조토를 산처리하였다. 산처리하므로써 알카리 함량이 저하되고, 비표면적은 증가하며, 또한 Al₂O₃의 함량이 낮은 규조토를 사용한 β-Sialon에서는 미반응 Al₂O₃가 존재하지 않았다. β-Sialon was synthesized from diatomaceous earth which had the lower content of Al₂O₃ than kaolin. Diatomaceous earth was treated by acid in order to reduce impurity level and to increase reactivity. Contents of alkali were reduced and specific surface area was increased in acid treated samples. Free Al₂O₃ did not exist in the final samples which were synthesized from the low Al₂O₃ contented diatomaceous earth.

憂鬱病의 發病前 社會環境的 要因에 대한 考察

오세원,엄용섭 大韓神經精神醫學會 1980 신경정신의학 Vol.19 No.3

This clinical study was made to investigate the socio-environmental stressors occurring prior to the onset of severe depression in 85 patients who were hospitalized in the Neuro-Psychiatric Department of Chosun University Hospital from September, 1976 until December, 1979. The result were as follows: 1. According to the diagnostic distribution, 54 were cases of "nonendogenous" depression and 31 were cases of "endogenous" depression. Among them, 71% of the endogenous depressives and 28% of the nonendogenous depressive had a past history of deprission. 2. Frequency of the socio-environmental stressors prior to the onset of depressive illness were (1) financial problems(55.3%) (2) conflict among family members(42.4%) (3) failure of patient's children to meet parental expectations(27.1%) (4) failure in job performance or increased responsibities(27.1%) (5) made to face denied reality(25.9%) (6) threat to sexual identity(23.5%) (7) physical illness(22.4%) (8) change in marital relationship(22.4%) (9) damage to social status(12.9%) (10) death of important person(12.9%). 3. Of the patient, 27 cases were male and 58 were fomale. Most of the cases were distributed in the late adulthood range. The more frequent stressors in male patients were financial problems aned failure in job performance or increased responsibilities. In female patients, financial problems, conflict among family members and failure of patient's children to meet parental expectations were the most frequent stressors. 4. The frequency and type of socio-environmental stressors were similar in both the endogenous and nonendogenous groups. Frequency of stressors in the endogenous group was in the order of financial problems(58.0%), failurein job performance or increased reaponsibilities(38.7%), made to face denied reality(35.5%), conflict among family members(25.8%), failure of patient's children to meet parental expectations(25.8%), physical illness(25.8%), threat to sexual identity(25.8%). The frenquency of stressors in the nonendogenous group was in the order of financial proplems(53.7%), conflict among family members(51.8%), failure of patient's children to meet parental expectations(29.4%), threat to sexual identity(22.2%), change in marital relationship(22.2%). 5. Internal psychological reactions to socio-enviromrntal exteranl events seemed to be determined by individual psychopathology and internally-underlying psychological conflict.

정상인과 정신지체인의 치아우식증과 치아우식 원인균, 타액내 면역항체의 비교

최세원,양규호,최남기,강미선,임회순,오종석,김선미 대한소아치과학회 2007 大韓小兒齒科學會誌 Vol.34 No.3

신체운동으로 단련된 사람에서의 운동부하후 심폐기능 회복반응에 관한 연구

심동원,심세홍 순천향대학교 1989 논문집 Vol.12 No.1

This treatise gains the following results, measuring the number and recovery response of heart beats, blood pressure, the frequency and recovery response of breathing and tidal volume through the cardiopulmonary function to the trained persons with long-term and limited physical work load as an object of study on the males of the Middle-and-Mature aged applicable to the fourties and fifties. 1. Heart beats and Blood pressure At the time put in rest form a training group, as for the number of heart beats, its number is an average 69.1 per minute and it shows the lower value by 8% as compard with of 74.7 for normal control group. As for the value of blood pressure, its value is an average 142 mmHg(Systolic Pressure)/103 mmHg(Diastelic Pressure) and it shows the slighily higher value as compared with of 134 mmHg/84 mmHg for normal control group, but its avlue is diffcult to come to conclusion significantly. 2. Frequency of Breathing and Tidal Volume As for the frequency of respiration, when the rest is put in from a training group, its frequency shows an average 14.0 per minute, but the value is lower by about 12.5% than than of 16.1 of normal control person when they put in a rest, the tidal volume for a time shows the value of 594.6 ml more by about 20% when in a trainin group. 3. Recovery response after exercise about Heart Bearts and Blood Pressure As for the number of heart beats, recovery response after exercise is from training group, its number is an average 69.1±6.64 minute(before exercise), 73.6±7.94 per minute(in fiftee minute) and it shows the rapid recovery as compard with of 74.7±3.64 per minute(before exercise). 81.54±4.33 per minute (in fiftee minute) for normal control group. As for the value of Blood Pressure, recovery response after exercise is from training group, its value is an average 142 mmHg(Systolic Pressure)/100mmHg(Diastolic Pressure)(before exercise) 140mmHg(Systolic Pressure)/ 94mmHg(Diastolic Pressure) and, its value shows the same valuation of recovery time as compared with of 134 mmHg/84mmHg(before exercise), 136mmHg/71mmHg(in fiftee minute) for non-training group. 4. Revoerry response after exercise about Frequency of Breathing and Tidal Volume As for the frequency of respiration, recovery after exercise is from training group, its frequency is a average 14.0±1.83(before exercise) 27.0±4.21(immediatly post-exercise) 16.0±5.36(in fiftee minute) and it shows the repid recovery as compared with 16.1±2.04(before exercise) 36.6±3.42(immediatly post-exercise) 246±6.65(fifteen minute) normal control group. As for tidal volume, recovery response after exercise is from training group its volume is an average 2161.6±298.2 ml(immediatly post-exercise) 675.0±61.76 ml(fifteen minute) it shows the slightly rapid recovery as compared with 494.9±29.29 ml(before exercise) 2666.6±458.9 ml(immediatly post-exercise) 780±74.32ml(fifteen inture) for normal control group.

바퀴의 變態에 따른 中腸의 組織學的 硏究

吳世源,趙德炫 광주보건대학 1984 論文集 Vol.9 No.-

The epithelium of the mid-gut of Blattella germanica L. classified cockroaches was observed with light microscope. 1. The mid-gut structure was composed of peritrophic membrane, epithelium cell, basement membrane and muscles. 2. The epithelium of mid-gut was composed of columnar, goblet and regenerative cells. 3. A regenerative cell was taken the place of epithelium cellsecration enzyme by destrctive metabolism. 4. Mid-gut structure does not change during the metamorphosis.

專門大學 齒科衛生科 敎育課程 修正·補完에 關한 硏究

吳世源,鄭萬泰,趙民貞 광주보건대학 1989 論文集 Vol.14 No.-

The purpose of this study is to modify the curriculum of department of dental hygiene. The specific objectives of this study are: 1. To analyze the curriculum of dental hygiene in Korean junior college. 2. To analyze the curriculum of dental hygiene in foriegn junior college. 3. To analyze the questionnaire on the complementary modification of the curriculum of department of dental hygiene. In order to accomplish the above objectives, curriculum of department of dental hygiene in Korean 10 junior colleges and the curriculum of the ministry of education were analyzed varietily also, curriculum of the department of dental hygiene in foriegn some junior colleges were analyzed by the researcher and 56 dentists, 22 professors of the department of dental hygiene and 11% dental hygienists were randomly selected in Korea a s subjects of the study. The instruments such as modification of the curriculum scale developed by Prof. Nam, Prof. Kim and Prof. Ma were used in this study. However, some items of these scales were modified by the researcher. The statistical method employed in this study was a percentage. From this analysis the following conclusions were drawn : 1. In curriculum of the department of dental hygiene in Korean junior college, establishing hours, credits, subjects in a subject of special study turned out to be scant for the curriculum of the ministry of education. 2. In curriculum of the department of dental hygiene in Korean junior college, an overall complection credit, a credit of a subject of special study, turned out torriculum of the department of dental hygiene in Korean junior college, out to be scanty for the American colleges while the completion credit of a general course turned out to be ample and an overall completion hours and subjects of a subject of special study turned out to be scanty for Holland and Japan. 3. In questionnaire analysis Professors hopped that a acquistion of technician qualification subject of specal study increase in completion unit. Dental hygienists hopped increasing of subject of special study, insureing of clinical practice, and insureing of clinical treatment of patients. Dentists hopped dental of patients and occupational moral.