PWM을 이용한 전압형 D급 (ZCS) 고주파 인버터의 특성해석 및 회로 설계

이봉섭,김종해 三陟大學校 1998 論文集 Vol.31 No.1

This paper presents operating characteristics of the main power conversion for voltage-fed type D(ZCS) class high frequency inverter using PWM. Recently, when the switch is turn on and off, make the current or voltage resonant, the ZVS(Zero Voltage Switching) and ZCS(Zero Current Switching) method to make the voltage or current into zero publicated actively read a paper. This papr was described about principle and form of proposed circuit made use of soft switching technology ZCS (Zero Current Switching) to reduce turn on and off loss at switching. Also, the analysis of the proposed circuit is described generally by using normalized parameter and basic operating principle and driving characteristics have been evaluated as to switching frequency and load parameter. The experimental results shown that the proposed Inverter can be used practically such as power source system for induction cooker etc.

중학교축구선수의 집단응집력과 성원만족 및 팀성공과의 관계

이창섭,임종은,석원웅 忠南大學校體育科學硏究所 1998 體育科學硏究誌 Vol.16 No.1

The purpose of this study was to verify the hypothetical method by identifying the influence of cohesiveness on member satisfaction and team success in middle school soccer players. Subjects for this study were 183 soccer players from 10 soccer teams at middle school level in Taejon city, Chungnam and Chungbuk Province. For the data analysis multiple regression and correlation method was calculated. The major findings of this study were as follows: 1. In the subfactor of cohesiveness. the significant influence showed in the feeling of social group attachment on the satisfaction to game, the subjective group unification or social group unification on the satisfaction of the position. and the subjective group unification on the satisfaction of the position. and the subjective attachment on the satisfaction of belonging. 2. The subjective group attachment and the subjective group unification showed significant influences on the team scoring. and subjective group attachment showed significant effect on the loss of score and the percentage of victories.

2-염화안트라퀴논카르보닐과 메타-치환아닐린과의 친핵성치환반응

李鍾八,嚴泰燮 東亞大學校 大學院 1983 大學院論文集 Vol.7 No.-

Pseudo-first order rate constants k ???. were determined for the reaction of Anthrauqinone-2-carbonylchoride with meta-substituted Anilines (m-CH₃,H, m-CL, m-NO₂) in acetone, The second rate constants k²were then determined from k???. The slopes β of Bronsted plot and ρ of Hammett plot have been calculated (β=0.41∼0.47)(ρ=-0.83∼1.18) and studied the transition state variation caused by the effect of substituents. These results suggest that transition state variation which has developed more bond cleavage than bond formation. As isokinetic temperature β values appeared all higher than experiment temperature from isokinetic relationship, reactions proceed entrope control. It was concluded that the reaction proceed via the dissociative S??2 mechanism.

N-테노일 이미다졸 유도체의 가수분해반응

이종팔,성대동,엄태섭 東亞大學校 大學院 1994 大學院論文集 Vol.19 No.-

The oseudo first order rates for hydrolses of N-thenoylimidazole(N-TI), N-thenoylbenzimidazole and N-thenoyl-2-phenylimidazole(N-TPI) have been determined at over all pH range with the ionic strength of 0.5M KCl at 40℃ by spectrometry. Hydronium ion and hydroxide in catalyzed reaction observed. The reaction of the diprotonated species occured at pH=3.5 in N-TI and at less than pH=6 in N-TPI. Metal ion catalyses were observed very weakly in hydrolyses of these compounds in the presence of divalent metal ions Cu², Ni², or Zn². We have observed that metal ion promoted hydronium ion catalyzed reaction. Saturation effects were observed only in the metal ion catalyzed hydrolysis of N-TI.

氣合소리와 筋力과의 관계

李鍾虎,李昌燮 충남대학교 자연과학연구소 1983 忠南科學硏究誌 Vol.10 No.1

The purpose of this study was to see the effect and to understand the general tendency of shouting for concentration of spirit to strength during exercise. Randomly sampled 16 male college students were measured grip strength and back strength and 2 male college students were measured electromyogram according to the shouting for conentration of spirit. And 123 male and female college students answered the questionaire for this study. The following conclusions were obtained. 1. A large part of people shout oneself for concentration of spirit and mental stability and think that shouting for concentration is effective during exercise. 2. Many people shout oneself specially during lifting, pushing and pulling of heavy something. 3. There was no significant difference of grip and back strength according to the shouting for concentration of spirit. 4. There was no significant change of electromyogram according to the shouting for concentration of spirit measuring grip and back strength.

9세 소아에서 나타난 비구개낭의 치험례 : CASE REPORT

이상호,모경희,박종휘,이난영,이창섭,윤정훈 大韓小兒齒科學會 2003 大韓小兒齒科學會誌 Vol.30 No.3

비구개낭은 절치관낭이라고도 불리우며 가장 흔한 비치성낭이다. 발육성으로 비구개관내에서 태생 상피잔사가 증식하여 낭변성을 일으킴으로써 발생한다. 비구개낭은 악골낭의 약 1.7-11.9%를 차지하며 남자에게서 약 3배 정도 호발한다. 연령분포는 매우 광범위하나 대개 40대에서 60대 사이에서 발견되며 10세 이전에 발견되는 경우는 매우 드물다. 비구개낭을 위한 적절한 치료는 적출이며 비구개신경에 손상을 가하지 않도록 해야 한다. 낭이 커서 치아의 생활력에 영향을 주거나 비구강누공이나 구강 상악동 누공을 형성할 우려가 있을 경우에는 조대술로 치료할 수 있다. 본 증례의 환아는 구개부의 무통성 종창을 주소로 내원하여 임상 및 방사선 검사를 실시한 결과 소아에서 매우 드물게 나타나는 비구개낭으로 방사선사진에 32×25.5mm크기를 나타내었으며, 매우 팽창되어 순측 피질골판을 관통하고 상순소대 하방과 전정부위까지 종창되어 있었다. 병소와 인접한 상악 4전치 치근은 심하게 이개되어 있었다. 낭의 크기가 매우 커서 조대술을 시행하였으며 obturator를 장착하고 있으며 향후 계속 관찰이 요한다. Nasopalatine duct cyst(NPDC) is the most common non-odontogenic cyst in the oral area and is thought to be originated from the epithelial remnants of the nasopalatine duct. Many etiologic factors have been proposed for the NPDC; trauma to the region during mastication of from ill fitting dentures, bacterial infection, and spontanious proliferation of tissue. The majority of cases are seen between the ages of 40th and 60th and it is rare in children. Surgical enucleation is the recommended treatment for NPDC, usually under general anaesthesia. A 9-year-old boy was refered to the chosun university pedodontics clinic that this child who has anterior palatal swelling is in routine check. In this case, swelling was presented at the bottom of the anterior nasal cavity as well as in the labial aspect of the upper alveolar ridge. It was so large that we treated it by marsupialization and obturator was put. This patient is on the continuous observation. We treated the child who had NPDC by marsupialization, and got the successful results such as rapid bone regeneration and the consistency of incisor vitality.

運動選手의 징크스 發生 및 所持原因分析

李鍾虎,崔大雨,李昌燮 충남대학교 자연과학연구소 1989 忠南科學硏究誌 Vol.16 No.1

This study was performed to grasp and understand the Cause of possession and origination in Athlete's Jinx that is considered as a affecting psychological factor for peak performance. To characterize the Jinx, 16sports coach and 25male and 13female athletes were interviewed. Then all possible psychological theory and presented study was reviewed. Following conclusions were obtained. 1. Characteristics of Jinx. a)Superstitious behavior or thought is rather negative than positive, b)became more powerful when losing than winning, c)almost Athletes don't know when, where and how the jinx originated with them, d)in general, negative when the jinx is associated with person of living thing, and e)Jinx can affect performance positively or negatively. 2. Causes of possession and origination in Athlete's Jinx. a)Association-reinforcement and blaming someone else and something else, b)negative thought and lack of confidence, c)excessive level of anxiety, arousal and stress, d)fear of failure and success phobia, e)lack of knowledge about sports psychology, f)Sociological and environmental factors such as audience, expentancy and g)poor progress resulted from plateaus, slumps, staleness in performance.

冠岳樹木園地域內 荒廢山地土壤의 肥沃化를 통한 綠化促進에 關한 硏究

李宗學,麻鎬燮,李憲浩,權台鎬,禹保命 서울大學校 農科大學 1984 서울대농학연구지 Vol.9 No.2

冠岳樹木園地域의 山復斜面은 地質的으로 대보화강암에서 풍화생성된 거친 돌부수러기가 많은 粗砂質壤土로 구성되었으므로 表土層의 土壤流矢이 심하여 土深이 대단히 얕거나 岩盤露出이 심하여 林木生長이 심히 不良한 地帶로서, 山地의 地力恢復 및 現存하는 散生樹木의 生長力恢復을 通한 山地綠化保全이 시급히 요청되고 있다. 이와같은 요청에 부응하여 荒廢地斜面에 自生하고 있는 주요한 4樹種(소나무, 리기다소나무, 노간주나무, 철쭉)에 대하여 山地施肥效果 試驗을 春期와 秋期로 나누어 실시한 결과 樹高 및 直徑生長量에 있어서 無施肥區에 比하여 현저한 施肥效果가 인정되었다. 따라서 冠岳山地帶의 荒廢地를 조속히 復舊綠化하기 위해서는 砂防土木的 工事方法 및 砂方造林的 播植方法이외에도 현존 수목의 保全 및 生長力恢復을 통한 速成綠化方法도 채용되어야 할 것이다. Hillsides in the Kwanak arboretum area were composed mainly of coarse sandy loam having relatively high proportion of rough weathered debris derived from the Daebo granite geologically. Owing to heavy soil erosion resulted to shallow soil depth and heavy rock exposures, the growing trees in this type of surface soil are very poor in their growth. For woody plant vegetation establishment in this montain area, it is urgent to recover the fertility of soil and the growth of existing trees. For this purpose, in spring and autumn season in 1983~84 the fertilization experiment was conducted with the 4 principal native species(Pinus densifltora, Pinus rigida, Juniperus rigida, Rhododendron schlippenbachii) growing in this denuded forest land, and the effects of fertilized tree plots were more prominent than the control plot in both height and root-collar diameter growth. Therefore, the accelerating measures of vegetation rehabilitation through conservation of existing trees and recovery of tree growth by forest fertilization practices, besides forest engineering measur es and soil erosion control afforestation measures, could be acceptable as the measures for the recovery of denuded forest land in Mt. Kwanak area.

대학생의 정치적 태도에 관한 연구

이창섭,이종호,김헌 충남대학교 체육과학연구소 2000 體育科學硏究誌 Vol.18 No.1

The purpose of this study was to analyze and compare three individual facets of political attitudes by a university student classification and gender, exercise experiences. The subjects were 402 university students randomly chosen from various student classifications 165 students were among physical education department and 237 among general department students. For the purpose of this study, this study used a survey instrument modified by the researcher and based on the various variables identified in an extensive review of related literature. The survey instrument contains three factors; political orientation, political participation and political interest. An independent samples t-test was used to analyze the col1ected data. The results revealed that significant differences were found between the perception of the two types of students on the dimensions political interest : (1) Regarding the comparison of political orientation between university student classification, physical education students showed slightly more progressive than the other university student group ; (2) Pertaining to the comparison of political participation and political interest between university student groups, physical education students showed higher than the other group. According to gender, significant differences were existed in the two factors, political orientation and political participation. No significant differences was existed between athletes and non-athletes in the three facets of political attitudes.

冠岳樹木園地域內 荒廢山地土壤의 肥沃化를 통한 綠化促進에 關한 硏究(Ⅱ)

李峻雨,李宗學,權台鎬,禹保命,麻鎬燮,金景河 서울大學校農業生命科學大學附屬樹木園 1986 서울大學校 樹木園 硏究報告 Vol.- No.7

The shallow soil depth and severe rock exposures on the hillslopes in the Kwanak aboretum area which resulted from the heavy soil erosion have made very poor growth of forest vegetation. In order to establish the forest vegetation in this area, it is urgent to recover the fertility of soil and the productivity of existing trees. For this reason, fertilization experiment (using the briquet compound fertilizer) was conducted on summer and autumn season in 1983 with the 4 main native species (Pinus densiflora, Pinus rigida, Juniperus rigida, Rhododendron schlippenbachii) growing on these eroded hillslopes. Result in 1985 and 1986 of this experiment represented that the fertilization was effective toward both height and root-collar diameter growth of trees and spring fertilization was, relatively, more effective than autumn fertilization. It also represented that effects of fertilization to P. rigida were more than those to other species. Therefore, besides the engineering methods and afforestation measures for soil erosion control, rapid establishment of vegetation through conservation and recovery of existing trees by fertilization is available measures for the rehabilitation of rockily eroded hillslopes like Mt. Kwanak area.