Digital Converter로 구동되는 크레인용 직류전동기 속도제어 시스템의 안정도 해석

변성태,김종훈,정태동,구태만 울산대학교 1996 공학연구논문집 Vol.27 No.1

크레인 구동용으로 antiparallel converter의 반도체 전력회로에 마이크로 제어기를 사용한 직류전동기의 속도제어 시스템에 대한 안정영역을 해석한다. 먼저 불연속 전류인 경우 converter의 비선형특성으로 인하여 전동기 속도제어 능력이 저하되므로 이를 보상하는 방식을 제안한다. 이 converter와 직류전동기를 포함한 전체 속도제어 시스템을 이산형 상태방적식으로 모델링 한 후, 각 제어기 이득에 대한 안정영역을 해석한다. The stability regions for microcontroller-based dc motor speed control system driven by antiparallel converter, which has been used as the crane drive, are analyzed, first as the performance of motor speed control is deteriorated due to nonlinear characteristics of the converter in the discontinous current state, the method to compense for nonlinear characteristics of the converter is suggested. The overall dc motor speed control system including the converter and dc motor is represented by a discrete-time state equation, and then the stability regions for gains of controllers are dervied.

공구 수명의 신뢰성 예측 프로그램 개발

이수훈,김봉석,강태한,송준엽,강재훈,서천석 한국공작기계학회 2004 한국공작기계학회 춘계학술대회논문집 Vol.2004 No.-

This paper deals with a prediction method of tool life in view of the reliability assessment. In this study, the flank wear was studied among multi-factors deciding the tool wear state. Firstly, tool life was predicted by correlation between flank wear and cutting time, based on the extended Taylor tool life equation of turning data, including parameters of cutting speed, feed rate, and cutting depth. Secondly, each of cutting conditions of endmilling was equivalently converted to apply ball endmill data to the extended Taylor equation. The web-based reliability prediction program for tool life is being developed as one of reliability assessment programs to for the machine tools.

Prochiral 탄소를 갖는 화합물에서 광학활성체 합성(Ⅱ)

鄭泰明,朴基勳 慶尙大學校 1987 論文集 Vol.26 No.1

The chiral heterocycle groups as an auxiliary use for asymmetric synthesis, Especially C-4chiral thiazolidine -2-thione has been shown to most effective for the regioselectivity of asymmetric synthesis. In order to increase the differentiation of regioselectivity between to idential groups in prochiral symmetric dicarboxylic acids. I selected 4(S)-isopropy1-1, 3-thiazolidine-2-thione [4(S)-IPTT which was synthesized from L-valine as an auxiliary. The 3-methy[ glutaric acid was reacted with 4(S)-IPTT in presence of DCC in pyridne, to give 1,5-di[4(S)-isoprony1-2-thione-1,3-thiazolidinyl]-3-methyl-1,5-pentanedione. This diamide was subjected to aminolysis with 1 molar equivalent of piperidine in CH₂Cl₂at low temperature. As resutl, very nigh regioselectivity of the reaction was observed in case.

人蔘이 햄스터의 血色素와 A/G率에 미치는 영향에 관하여

孔泰勳 동국대학교 농림과학연구소 1969 農林科學 論文集 Vol.3 No.-

Giving unprocessed ginseng to the hamster(Mesocricetus auratus) a gram per day for 25 days, I obtained the following results : 1. A significant increase in hemoglobin has been registered as a result of the supply of ginseng. 2. A significant increase in the serum-total protein has also been recorded after 15th day of the supply of ginseng. 3. Outwardly, it shows A/G rotio gradully increasing from the 10th day following the supply of ginseng. But the significant increase in shown ofter 25th day of ginseng supply. This means that the component of allumin has increased more than that of globutin. In short, the Hb and total protein and albumin in serum increase as a results of 25 days of giving ginseng to the hamsters.

FMEA를 이용한 기계류 시스템의 신뢰도 분석

진도훈,우태수,이치우 한국공작기계학회 2002 한국공작기계학회 추계학술대회논문집 Vol.2002 No.-

This paper dealt with FMEA, which is a method of the analysis to secure safety and confidence coming up to customers' expectation in consideration of the environment of the corporation, the industrial environment, and the functional improvement. And by using FMEA, We showed the example analyzed the confidence of the Air Supply System. It was proved by the result of the analysis that the rate of the breakdown which is usually regarded as the first important point to reform can't satisfy the selecting basis to improve. Also the result said that it is not right to depend on only the rate of the failure in making the list of the reform. Through the analysis of the breakdown, FMEA can present the important factors of the reform to improve the confidence of the system. In this study would show the important factors of the improvement in order to product the goods guaranteed confidence through the method of FMEA.

가토에서 흡수성 차폐막 Biomech®의 골재생 효과

김태훈,유선열 전남대학교 치의학연구소 2001 구강과학 Vol.13 No.3

The purpose of the present study was to investigate the effect of absorbable membrane (BioMesh®) on bone regeneration in the rabbit by evaluating biodegradability, biocompatibility and bone regenerative capacity. Eight rabbits, weighing about 2kg, were used. Two bone defects, 8 mm in diameter and 7 mm in depth, were made. In the experimental group, the bone defect was covered with BioMesh® absorbable membrane. In the control group, induced spontaneous healing. The rabbits were sacrificed at 2, 4, 6, and 8 weeks after the operation. Radiographic and microscopic examination were performed. Results obtained were as follows: After 2 weeks, proliferation of the fibrous tissue was observed in the control group, but the newly formed cartilage and more active bone formation were noted in the experimental group. After 4 weeks, the new bone formation appeared in the control group, and in the experimental group, the bone trabeculi were densely aligned and matured. After 6 weeks, complete resorption of the BioMesh® membrane occurred in the experimental group. Both experimental and control group acquired dense osseous coverage, after 8 weeks. These results suggest that the BioMesh® absorbable membrane contributes new bone formation by guiding bone regeneration in the early stage.

제30회 전국소년체육대회 경남 선수단 성적분석

이강헌,김태진 창원대학교 체육과학연구소 2001 경남 체육연구 Vol.6 No.2

본 연구는 제30회 전국소년체육대회에서의 경남선수단 성적을 분석한 것이다. 제21회 대회 이후 메달 수에 의하여 시도별 순위를 비공식적으로 산출한 경남의 경기력은 22회 대회부터 제 25회 대회까지 연속 4년 동안 종합 3위를 기록하는 좋은 성적을 기록하였다. 울산의 광역시 승격으로 분리된 후 개최된 제27회 대회에서 7위를 기록하여 중위권을 기록하였으나 1999년도에 개최된 제28회 대회에서 다시 종합 3위를 기록하는 등 일반적으로 고등부와 성인들의 대회인 전국체전에 비하여 좋은 성적을 보여왔으나, 29회 대회에서는 9개 종목에서 금메달 16개만을 획득하여 금메달 순위 11위에 머무는 등의 부진한 성적을 거두었다. 그러나 2001년 제30회 소년 체전에서는 지난해 보다 향상된 금메달 21개로 종합 7위를 차지하는 등 경남체육에 있어 회생의 발판을 마련하였다. 특히, 양궁에서 16개의 금메달중 7개를 획득하였고, 단체경기 총 42개팀이 참가하여 17개팀이 입상하는 퀘거를 이룩하였다. 그러나 예년과 마찬가지로 경남은 종목별 경기력 편차 문제를 극복하지 못하였고, 그 심각성을 여실히 드러내었다. 육상, 수영, 체조 등 기본종목(총 금메달 148개)에서 금메달을 1개도 획득하지 못하였고, 개인 다 메달 종목인 레슬링, 역도, 유도, 태권도(총 금메달 106개)에서 4개의 금메달(레슬링 2개, 역도 1개, 태권도 1개) 밖에 획득하지 못하는 부진을 보였다. 이러한 측면에서 본 연구에서는 경남체육의 경기력 향상을 위한 몇 가지 방안을 제시하고자 한다. 첫째, 기본 종목인 육상, 수영, 체조와 다 메달 종목인 레슬링, 역도, 유도, 태권도 종목에 역점을 두고 근본적인 대책수립과 선수저변확대가 필요하다. 둘째, 각 시·군 교육청은 학교별 육성종목을 재검토하도록 하고 육성종목은 교육장 책임하에 전국소년체육대회에서 필히 입상할 수 있도록 장·단기 계획을 수립·추진하여야 할 것이다. 셋째, 장기적이고 안정적인 경기력 향상 방안으로 교육청별 특정 종목을 연계육성을 위하여 해당 지역 내에서 팀 창단을 유도하고 지속적인 신인선수 발굴을 위한 제도적 장치 마련하여야 할 것이다. 넷째, 도교육청, 체육회, 경기단체는 전국소년체전을 대비하여 지속적인 상호 유대관계를 강화하여야 할 것이다.

마그레브 地域의 무슬림 宣敎를 위한 基督敎敎會의 狀況化에 관한 硏究

장훈태 기독신학대학원대학교 2002 기독신학저널 Vol.3 No.-

가상공간의 가공 공정과 상태 구현에 관한 연구

이수훈,김봉석,홍민성,김종민,JUN NI,박상호,송준엽,이창우,하태호 한국공작기계학회 2005 한국공작기계학회 춘계학술대회논문집 Vol.2005 No.-

This paper presents virtual machining system in order to realize turning process in virtual space. A reliable virtual turning process simulation was developed based on the surface shaping system which is capable of considering geometric model, thermal error model, and vibration model. Accuracy of surface shape resulting from proposed machining simulator was verified experimentally. This paper also developed the watchdog agent that continuously assessed, diagnosed, and predicted performance of products and machines in machining. The Watchdog agent extracted feature signal using time-frequency analysis among various signals from multi-sensor and evaluated machining condition using performance confidence value.

공작 기계의 신뢰성 평가를 위한 웹 기반 해석 프로그램 개발

강태한,김봉석,이수훈,송준엽,강재훈 한국공작기계학회 2004 한국공작기계학회 추계학술대회논문집 Vol.2004 No.-

Web-based analysis programs for reliability assessment of machine tools were developed in this study. First, the reliability data analysis program was developed to search for failure rate using failure data and reliability test data of mechanical part. Second, failure mode analysis was developed through performance tests like circular movement test vibration test for machine tools. This analysis program shows correlation between failure mode and performance test result. Third, tool life was predicted by correlation between flank wear and cutting time, using the extended Taylor tool life equation in turning data and the equivalently converted equation in order to apply ball endmill data to Taylor tool life equation in milling data. All the information related to input and result data can be stored in theses programs.