DSP 소프트웨어에 의한 전력변환기 게이팅 신호 발생

이해춘,박태열,김기택 江原大學校 産業技術硏究所 2001 産業技術硏究 Vol.21 No.A

Power converters are widely used in the applications of servo drives of ac and dc motors and power supplies. For the control of the converters carious control algorithms hate been proposed and realized by gating signal generation. Software control shemes are being applied to implement the control algorithms, but analog circuits are still used fort the gating signal generation because it requires verb fast and precise timing. In this paper the gating signal generation with DSP software are proposed for the three phase to three phase PWM converter. Design procedures and software flowcharts are presented and some experimental waveforms are also presented to verify the proposed algorithms.

韓國中小企業의 國際競爭力 强化方案

李春基 건국대학교 1982 商經論叢 Vol.- No.17

기독교신앙이 대기업 사무직 직장인의 스트레스 과정에 미치는 완충효과

이정호,전성일,이기철,최영민 大韓神經精神醫學會 1998 신경정신의학 Vol.37 No.5

연구목적 : 기독교 신앙이 직장인의 스트레스지각과 대처 및 스트레스로 인한 우울과 불안에 미치는 완충영향들을 조사하고자 하였다. 연구방법 : 대기업 직장인 545명을 대상으로 피검자 단독 보고형 설문지를 작성하게 하였다. 설문지는 연구 목적에 대한 설명과 인구학적 조사를 포함하여, 2개의 신앙척도, 직장 스트레스척도, 일상생활 스트레스 지각척도, 대처 방식 척도, 그리고 우울과 불안 척도로 구성하였다. 결 과 : 생활 스트레스와 직장 스트레스를 지각하는 면에서는 신앙을 가지지 않은 사람들과 기독교 신앙인 사이에 차이가 없었다. 그러나 스트레스 대처에서는 기독교 신앙을 가지지 않은 사람들과 기독교 신앙인 사이에 차이가 있었다. 정서중심대처를 제외한 문제중심대처, 소망적 사고, 사회지지 추구 대처에서 모두 의미있는 차이가 있었다. 스트레스의 최종적인 결과로서 기독교 신앙 집단이 비기독교 집단에 비해 우울감정과 상태불안 그리고 기질불안 모두가 다 낮았다. 기독교 신앙을 '기독교적 사고'와 '기독교적 생활'로 구분하여 스트레스 완충기능을을 구체적으로 살펴보면, '기독교적 사고'는 직장인이 스트레스를 지각하는 데에는 아무런 영향을 주지 못하였고. 대처방식에서도 정서중심적 대처를 강화시킴으로써 오히려 스트레스에 기인하는 불안을 증가시킬 수 있음을 나타내었다. 반면에 '기독교적 생활'은 직장스트레스를 덜 지각하게 하였고, 문제중심적 대처를 강화시킴을써 결과적으로 스트레스에 의한 우울과 불안을 감소시키는 것으로 나타났다. '기독교적 생활'은 소망적 사고라는 정서중심적 대처도 강화시켰는데, 이 경우는 문제중심적 대처와 정서중심적 대처가 서로의 기능을 촉진하는 것으로 볼 수 있다. 결 론 : 기독교 신앙은 직장인의 스트레스 대처를 강화시킴으로써 스트레스로 인한 불안을 감소시켰다. Objectives : The purpose of this study was to clarify the buffering effects of Christian belief on the interactional stress process of the white-collars. Methods : The sample of this study was 545 white-collars working in the large enterprise. The questionnaire was composed of demographic data, job stress questionnaire, global assessment of recent stress, the ways of coping checklist, Beck depression inventory, stait-trait anxiety inventory, and Shepherd Scale for differentiate Christians from non Christians. Christianity was divided into 'Christian way of thinking' and 'Christian way of living' for deep survey and analysis. Results : In recognizing life stress and job stress, there was no difference between Christians and non Christian atheist. But in coping stress, there was difference between Christians and non Christians. 'Christian way of thinking' strengthened emotion focused coping, but didn't play a buffering role in reducing stress-induced depression and anxiety of the white-collars But 'Christian way of living' increased challenge-appraisal and strengthened problem focused coping as a consequence. Also, Christian way of living had a influence on hoping thought and seeking social support. As a result, Christian belief reduced depression and anxiety. Conclusion : Christian belief had a buffering effect on the interactional stress process of the white-collars of large enterprises.

평판 및 쉘 구조물의 유한 요소해석을 위한 프로그램 개발

이기천,이태원 國立金烏工科大學校附設生産技術硏究所 1997 産業技術開發硏究 Vol.13 No.-

The original Mindlin-type degenerated plate and shell elements perform reasonably well for moderately thick shell structure. However, for thin shells when full integration is used to evaluate the stiffness matrix, overstiff solutions are often produced due to shear and membrane locking. To overcome the locking phenmena of the degenerated shell element, the assumed strain method is introduced. Using this approach, the finite element analysis program has been developed for the plate and shell under elastic conditions. The program are accommodated in a simple and effective manner by using a layered approach, where in two Gauss point integration scheme is adopted for each layer. Numerical tests for linear elastic problems show an improved performance of this program.

나리류 養液栽培時 培地種類 및 養掖濃度가 球根肥大와 切花品質에 미치는 影響

이춘용,이기환 公州大學校 資源科學硏究所 1998 資源科學硏究論文集 Vol.6 No.-

By studing on selection of optimal media and nutrient concentration in selected media so that carried out the influnance of bulb enlargment and quality of cut flower of hydroponicsis of lily. The result is following. 1. The sprouting was relatively fast in husk+peatmoss, perlite+peatmoss and, according to cultivars its rank was cv.Cherry Blossom, cv. Nove Cento, cv. Snow queen. The peroid of growing was short appromaxitively forty day in cv. nove cento, twenty day in cv.Snow Queen than that of spring planting. The quality of cut flower, that is plant height and number of flowers was excellent in fermented husk+fermented saw dust(7:3). 2. In the case of growing late, not only fresh weight increased remarkable but also degree of bulb enlargement revelaed greatly, when growing point of new bulb was differentiation. 3. The rate of bulb enlargement was remarkable difference between treatment according to nutrient concentration ; bulb weight , bulb diameter, bulb height, bulb width, number of scale and scale weight were very excellent in twofold standard soultion of Horticultural Experiment (N,30-P,6-K,12-Ca,16-mG,8me/1). 4. The quality of cut flower according to nutrient concentration, that is cut flower weight, cut flower height and leaf area were good when cv. Casa blanca was treated by standard soultion of H.E (N,15-P,3-K,6-Ca8-Mg,4me/l),cv. Elite was 1/2standard soultion of H.E.(N,7.5 -P, 1.5-K,3-Ca,4-Mg, 2ME/L) Gelria treated with twofold standard soultion of Horticultural Experiment was excellent in all of them above, but revealed bad for hardness of stem in the cv. casa blanca cultivars. 5. As a result of leaf analysis, all of cultivars revealed highly in rate of absorbance of nitrogen and potassium, when nutrient of high-concentration was treated Amount of absorbance of them remarkable increased in caseof cv. Elite cultivar, especilly absorbance of calcium was higher than other component. Amount absorbance of nitrogen in cv.casa blanca, according to high-concentration nutrient was much better but rate of absorbance of potassium weakly increased. Conseqencelly we know that nitrogen and potassium play an imporitant role in bulb enlargement and quality of cut flower. 6. The quality of bulb like bulb weight, bulb diameter, bulb width, bulb height, number of scale, scale weight were execellent as it cut thestem at 10 cm above the ground to reuse a bulb after cut flower.

GIS와 RS를 이용한 생태지도 작성기법에 관한 기초연구

이기철,이원화,윤해순,남춘희,김구연,김승환,서상현 한국지리정보학회 2004 한국지리정보학회지 Vol.7 No.3

본 연구는 낙동강 하구 일대의 생태계 변화와 생태 관련자료를 GIS DB로 구축하고 생태지도를 작성하였다. 생태지도 작성을 위해 1984년 11월 21일, 1997년 5월 17일에 촬영된 공간해상도 30m의 Landsat TM 위성영상과 국립지리원에서 발행된 1:25,000 수치지형도, 부산시에서 조사한 생물현황 자료를 바탕으로 DB를 구축하였다. 생태지도를 작성하기 위해, 첫째, 낙동강 하구 생태계 조사 보고서와 현재까지 진행된 생태지도에 대한 문헌 연구, 둘째, 시계열적 토지피복분류도 제작, 셋째, 동·식물상, 수질 등 생태계 항목별 BB 구축과 3단계 방식에 의한 생태계 평가, 최종적으로는 이러한 분석 결과를 바탕으로 생태계 관리를 위한 생태지도를 작성하였다. This study developed an ecological mapping technique with GIS database using the analyses of existing ecological survey reports and the change detection on the Nakdong river estuary. The data which are used to establish GIS DB include 2 Landsat TM images on Nov. 31, 1984 and May 17, 1997, 1:25, 000 topographical maps established by National Geography Institution and various ecological survey reports published by Busan metropolitan city government. The details for producing ecological map are as follows. At first, the current methods of ecomapping efforts and previous ecological surveys of Nakdong river estuary were carefully examined. Secondly, the land cover maps were created from the classified Landsat images of 1984 and 1997 for the spatiotemporal ecosystem analysis. Thirdly, the ecosystem was evaluated by using GIS ecological database based on the criteria of botany, zoology and water quality etc. Each criteria was reclassified into 3 stages which describe the overall quality of ecological condition. At last, the comprehensive ecological map was suggested as a prototype of ecosystem assesment and management tool with the discussion of further study. The findings of this study would be a milestone for preserving and managing the ecosystem.

앤더슨 모형을 이용한 우리나라 일부 대학생의 구강진료이용행태에 관한 연구

정기천,이흥수,김수남 대한구강보건학회 2003 大韓口腔保健學會誌 Vol.27 No.3

The purpose of this study is to provide framework for understanding university students' dental services utilization. In this paper Andersen model is applied to the analysis of dental services utilization. This model consists of predisposing, enabling, and need components that describe a person's decision to use dental health services. Questionnaire surveys were conducted for 521 university students. The number of independent variables used in the analysis was 36 in total, ie 25 predisposing components, 8 enabling components, and 3 need components. For statistical analyses of collected data, the multiple regression and the path analysis were adopted, The results obtained were as follows; 1. The proportion of student' dental visits was 41.5%, and the average of the dental visits was 2.33. 2. The purpose of most important recent utilization was dental caries treatment in university student. Also 4.4% of student visited dental clinic for oral disease prevention. 3. The amount of variance of the Andersen model for university student's dental visits was 16%. And of predisposing, enabling and need factors, which are components of the Andersen model, the need factors showed the largest amount of variance for university student's dental visits. 4. Number of restricted activity days caused by oral disease, having a regular dental care, socioeconomic status and perception on oral disease prevention were found to have significant major effects on dental services utilization of university student. Number of restricted activity days was most important factor affecting dental services utilization of student.

쑥갓의 생리활성 연구(Ⅱ)-STZ에 유도된 흰쥐에서의 과산화지질 생성계에 미치는 영향

정운용,천현욱,최종원,이용범,황기욱 慶星大學校 環境問題硏究所 1998 環境硏報 Vol.8 No.1

Chrysanthemum coronarium L. has long been used the appetite and constipation in oriental countries. We was investigated the effect on changes in serum and hepatic free radical generatin enzymes and free radical scavenging enzymes as well as detoxification mechanism of each fraction from Chrysanthemum coronarium by examining the induction of streptozotocin.(STZ) Male Sprague-Dawley rats(190∼210g), with free access to commercial rat chow (Cheil Foods & Chemical Inc.) and water, were divided into six groups : Group 1 served as normal; Group 4 received ethyl acetate fraction in STZ animal; Group 5 received butanol fraction in STZ animal; Group 6 received water fraction in STZ-induced rat. In the STZ-induced diabetic group, the serum superoxide dismutase activity decreased and formation of hydroxyl radical increased when dompared to normal. STZ caused increase hepatic lipid peroxide content was inhibited by treatment with Chrysanthemum coronarium butanol fraction and STZ decreased the hepatic glutathione compared to normal, but this was inhibited Chrysanthemum coronarium butanol fraction treatment.STZ induced change in hepatic microsomal cytochrome P-450 activity was inhibited by treatment with Chrysanthemum coronarium butanol fraction. STZ caused a significant rise in hepatic aniline hydroxylase and xanthine oxidase, decrease in aminopyrine N-demethylase when compared to normal. Activities of hepatic superoxide dismutase, catalase and glutathione peroxidase were significant rised by treatment with Chrysanthemum coronarium butanol fraction when compated to STZ. These results suggest that Chrysanthemum coronarium butanol fraction treatment suppressed STZ induced changes in serum and hepatic metabolizing enzymes system.

기독교 신앙이 외래 정신분열병 환자의 치료에 미치는 영향

최영민,이정호,이기철,전성일 大韓神經精神醫學會 1998 신경정신의학 Vol.37 No.6

연구목적: 정신의학적 치료과정에서 종교적 논점이 무시되거나 지나치게 적용되는 것에 대한 지적들은 있었으나, 구체적으로 종교적 믿음이 정 신분열병환자들의 치료과정에 어떤 영향을 미치는지에 대한 연구는 거의 없는 상태이다. 그래서 기독교 신앙이 통원치료 중인 정 신분열병 환자들의 치료과정에 어떤 영향을 미치는지를 구체적으로 알아보고자 하였다. 방법: GAF 점수가 41 이상으로 부분적인 병식 혹은 병식을 가지고 있으며 1년 6개월 이상 통원치료를 받고 있던 13명의 개신교일,정신분열병 환자들을 대상으로 전향적인 연구를하였다. 결 과: A. 긍정적 영향: 1) 치료자로서 환자들의 .신앙과 관련된 이야기를 편견없이 진지하게 받아준 것이 치료관계 형성에 매우 도움이 되었다. 2) 신앙이 마치 개인의 불안을 잠재워주는 도구와 같은 기능을 하기도 하였다. 3) 기독교인이라고 하는 사회적 자기정체성. 하나님의 자녀라는 신앙적 자기정체성, 하나님 과의 안전한 둘만의 관계체험.나는 하나님에 의해 언제나 받아들여진다는 느낌 교회에서의 안전한 수용체험 등이 정 신분열병 환자들의 자아정체성이나 자기개념의 발달에 도움을 주었다. 4) 신앙적 체험 흑은 영적인 깨달음을 통해서 알게된 신앙의 내용을 자신의 행동의 지침이나 청사진 처럼 사용하면서 도움을 받았다. 5) 정 신분열병 환자들이 하나님과의 관계에서 느끼는 보호받는 느낌. 수용받는 느낌 등의 둘 만의 관계 체험은 일상생활 속에서 다른 사람들과의 관계에서 경험할수 있는 체험과는 다른 종교의 고유한 심리 경험을 환자들에게 제공해 주었다. 마찬가지로 신앙체험이나 신앙의 내용을 자신의 행동의 지침이나 청사진 처럼 사용하면서 생활해 나가는 정신분열 환자들의 심리는 바람직한 일상생활 규범이나 일반적인 사회관습을 따르는 심리와는 전혀 다른 면이 있었다. 이러한 종교의 고유한 신앙체험이 치유적인 힘을 나타내는 것 같았다. B. 부정적 영향: 1) 교회 목회자나 교인들이 기도원과 같은 종교적 방법의 치유를 강요 혹은 권유함으로써 환자들과 가족들을 혼란시키고 치료과정에도 혼란을 가져오는 경우가 있었다. 2) 증상을 종교적으로 해석함으로써 증상에 대한 병식을 얻는 것을 방해하였다. 3) 신앙을 전체적으로 파악하지 못하고 문자적으로만 이해하는 인지적 결함의 위험성이 있었다. 4)지나치게 죄책감을 느끼며 자신을 징계하는 태도를 보이기도 하였다. 결론 : 기독교 신앙은 안정된 상태로 유지치료 중인 외래 정신분열병 환자의 치료과정에 많은 긍정적 영향과 부정적 영향을 미치는 것을 알 수 있었다. 정신과 의사들은 환자들을 치료할 때 신앙이 갖는 이러한 영향들을 신중하게 고려할 필요가 있겠다. . Objectives : Many psychiatrists ignore the behavioral and attitudinal aspects of religious beliefs of patients with schizophrenia. Therefore, how the Christian belief affects the treatment of schizophrenia was investigated. Methods : The subjects of the study were 13 schizophrenic outpatients with protestant belief having partial or full insight. GAf score of each of the patients was above 41. Results A. positive effects ; 1) Taking the patient's belief seriously without prejudice was helpful to therapeutic relation. 2) Faith fulfilled it's function of silencing the anxiety of the patients. 3) The factors which make schizophrenic patients develop serf-identity and self-concept in their religious lives were as follows : social identity as a Christian, religious identity as a child of God, experiences of safe dyadic relationship with God, feelings of being always accepted by God, and experiences of being accepted safely by the church.4) Faith experiences and spiritual enlightenment itself had a therapeutic impact on the patients as a guiding principle of their lives and blueprints for their actions. 5) Experiences of a safe dyadic relationship with God, feelings of being accepted by God, faith experiences, and spiritual enlightenment provided peculiar religious experiences which can not be found in everyday life. And these peculiar religious experiences seemed to have healing power. B. Negative effects; 1) The clergymen and the members of the church put the patients and their families into the confusion by compelling or recommending religious treatment methods like prayer retreats. 2) They interfered with patients getting insights by interpreting their symptoms religiously. 3) There was a risk of cognitive depfect of gasping faith literally.4) There was a tendency to direct punishment and blame inwards, on to the sef with guilty feelings. Conclusions : Christian belief exerted many influences both good and bad, on the treatment of the schizophrenic outpatients. We suggest that psychiatrists should consider the influence of the patient's faith upon the treatment.

측두하악 관절의 재건을 위한 늑연골 이식의 효과

김태규,정기돈,신상훈,김성길,이성근,박상준,서종천 大韓顎顔面成形再建外科學會 1996 Maxillofacial Plastic Reconstructive Surgery Vol.18 No.3

We performed costochondral grafting in mmandibular reconstruction including condyle replacement in 5 patients which have 4 cases of ameloblastoma, 1 case of resorption of left condyle due to osteomyelitis. We harvested the 6 th costochondral cartilage of unaffected side. No specific complications were appeared with unexpected fracture of costochondral junction and infection of operation site, These patients show 30-45mm at month opening, near normal of affected side, near normal or normal of unaffected side at lateral excursion. Postoperative coureses was uneventful with improved cosmetic and functional results. Our report is indicated that the costochondral graft is satisfactory to reconstruct mandibular defect including condyle replacement, especially in growing patients.