리니어 모터로 이송되는 탄성체의 진동 최소화를 위한 이송속도 최적화 연구

최영휴,홍대선,최응영,최국진 국립7개대학공동논문집간행위원회 2005 공업기술연구 Vol.5 No.-

Linear motor feed drive systems have been broadly used in machine tools or precision automatic systems. Recently, modern machine tools require high speed and high precision feed drive system to achieve high productivity. Unfortunately, a feed drive system, even though it was designed optimally, may experience severe transient vibrations during high-speed operation if its feed rate control is unsuitable. A rough feed rate curve having discontinuity in its acceleration profile causes serious vibrations in the feed slides system. This paper presents a feed rate optimization of a machine tool feed slide system, which is driven by a linear motor, for its minimum vibrations. Firstly, a 4-degree-of-freedom lumped parameter model is proposed for the vibration analysis of a linear motor driven machine tool feed drive system. Next, a feed rate optimization of the feed slide is carried out for minimum vibrations. The feed rate curve optimization strategy is to find out the most appropriate acceleration profile with jerk continuity. Of course, the optimized feed rate should approximate to the desired one as possible. A genetic algorithm with variable penalty function was used in this feed rate optimization.

지방공사의료원의 수익성 추이 및 관련요인 분석

최만규,이준협,이태로,이현실,임국환 高麗大學校 倂設 保健大學 保健科學硏究所 2003 保健科學論集 Vol.29 No.1

This study was attempted to identify trends and determinants of the profitability of Korean Provincial Hospitals different. Data used in this study were chosen from provincial hospitals that passed the standardization audit undertaken by the Korean Hospital Association from 1998 to 2001 for the purpose of accrediting training hospitals. There were collected from 19 provincial hospitals with complete general data of present conditions as well as financial statements(balance sheets, income statements). The dependent variables in this study were used net profit to total assets and operating profit to gross revenue as a proxy indicator for profitability. The independent variables were classified by general factors(location, teaching status, number of beds, period of establishment), operating and financial factors(current ratio, fixed ratio, liabilities to total assets, total asset turnover, average length of stay, bed occupancy rate, admission ratio of outpatients, patients per specialist, personnel costs per adjusted inpatient, material costs per adjusted inpatient, administrative costs per adjusted inpatient), in addition time leg effect(fiscal years). As a result of hierarchical multiple regression analyzation of net profit to total assets and operating profit to gross revenue, with general factors, operating and financial factors, adjusted R² of operating and financial factors is very powerful. The factors had significant positive effect on net profit to total assets were period of establishment, current ratio, admission ratio of outpatients. The factors had significant negative effect on net profit to total assets were average length of stay, personnel costs per adjusted inpatient, fiscal years. The factors had significant positive effect on operating profit to gross revenue were teaching status, fixed ratio, total asset turnover. The factors had significant negative effect on operating profit to gross revenue were location, liabilities to total assets, personnel costs per adjusted inpatient.

의료환경 변화에 대비한 의학기술부문의 교육방향

최종학,윤범철,조경진,이준협,임국환,고성진,최경호 高麗大學校 倂設 保健大學 保健科學硏究所 2003 保健科學論集 Vol.29 No.1

Under the pressure to open the service market as proposed by World Trade Organization, we can easily expect our educational systems for allied health professions will experience a lot of changes in near future. Accordingly, we compared our current educational systems for allied health professions with the foreign ones and mapped out some strategies predicting the forthcoming enormous changes. Major investigations and analysis are summed up as follows, The educational programs for allied health professions which was started in 1963 in Korea are stilled remained as 2 to 3 school years, while the systems in advanced countries have already been changed or been changing from 2 year to 4 year college levels. We can hardly find the uniform educational system or school years for the allied health professions in the world except for Korea. Fortunately, university level four-year programs for the profession was established in 1979 in Won-joo for the first time in Korea. However, there are still only few four-year programs in this country. To meet the rapidly changing needs we have faced in the health areas we should supply appropriate health personnel through various efforts. Now we would like to suggest followings, <Educational goals for the allied health professions> 1) reconfirming characteristics for the educational goals of health professions 2) extending school years for the allied health professions 3) strengthening clinical training and internship 4) expanding opportunities for the continuing education through lifelong education 5) upgrading from old-fashioned technologies to advanced technologies 6) cultivating competencies of health professionals for the global competition <Suggestions for the Development of Allied Health Professions> 1) reforming the school years of educational programs for the allied health professions to meet the global standards 2) expanding the role of junior college programs for the allied health professions through the development of intensive courses in the professions. 3) diversifying and specializing the allied health professions mainly through 4 year B.S. degree programs.

시판 요구르트의 비피더스균수 및 유산균수의 비교

최선규,김경민,강국희 성균관대학교 생명과학자원연구소 1996 生命資源科學硏究 Vol.3 No.1

This study was carried out to count of the number of lactic acid bacteria and bifido bacteria in commercial yogurts during transportation. Yogurts were collected from supermarkets in Suwon area and were stored at 10℃. Titratable acidity, pH, bifidobacteria count, and lactic acid bacteria count of commercial yoghurts. Titratable acidity was slowly increased from 0.8% to 1.2% and pH decreased from 3.88 to 4.5 at 10℃ during 12 days. Total range of lactic acid bacteria of the yogurts were 10^8-10^9 cfu/ml. For the bifidobacteria, some samples of B, N, P, S indicated 103.8-106 cfu/ml and products H, M, Y showed 10^7.8-10^8.8 cfu/ml during storage for 10 days. The number of lactic acid bacteria in all the sample products were contained over than 10^7 cfu/ml with regal level during transportation.

입학성적이 수학관련학과군의 학업성취도에 미치는 영향 분석

최국렬 인제대학교기초과학연구소 1999 자연과학 Vol.3 No.-

대학의 학생 선발 지표인 입학성적과 대학의 학업성취도를 나타내는 평점평균과의 관련성은 입시관계자는 물론 많은 대학관계자들의 연구대상이 되어 왔다. 본 논문은 현행 입시제도하에서 입학성적이 수학관련 학과군의 학업 성취도에 어떠한 영향을 미치는지를 통계적으로 분석·평가하고자 한다. 여기서 얻어진 결과는 요즈음 활발히 논의되고 있는 대학교육제도나 입시제도의 개혁에 적으나마 도움이 되는 기초자료를 제공할 수 있으리라 믿어진다. 분석자료는 1996, 97학년도 인제대학교 수학관련 학과군에 입학한 학생들의 입학성적과 96, 97년도의 평점평균을 대상으로 삼았다. The Predictive validity if two admission indices, HSG(High School Grade), SAT(Scholastic Aptitude Test)and social-demographic features, was evaluated by an ANCOVA model with the GPA(Grade Point Averge)for departments of mathmatics-related field at the JIJE university. The results was obtained from the students obtained admission in 1996 and 1997.

獨逸浪漫主義

崔國鉉 청주대학교 1966 論文集 Vol.5 No.1

평균 배기 압력 구배 지수를 이용한 실화 검출 방법

심국상,최민호,김세웅 金烏工科大學校 2000 論文集 Vol.21 No.-

This paper proposes a method to detect the misfired cylinder using a new misfire detection index. The new method of misfired cylinder is a comparison of pressure gradient during the blowdown period of exhaust stroke. If a misfire occurs, the engine will be lost some power and consumes the more fuel and the torque will be unsteady. Most of all, the misfire affects a bad influence of the 3-way catalyst and emits unburned hydrocarbon in the air. To prevent these unusual phenomena and eliminate the factor of the environmental pollution, it is important to detect the misfired cylinder. To do the experiment, set up the assist device on the conventional exhaust manifold. This assist device is not deformed for conventional exhaust manifold and installed in the end of the exhaust manifold. Experimental results showed that the method using the mean gradient pressure index is proven to be effective in the detection of misfired cylinder on gasoline engine regardless loads and revolutions of the engine

배기 다기관 형상 변경에 따른 배기계에서의 배기 압력 특성에 관한 연구

심국상,최민호,김세웅 금오공과대학교 산업기술개발연구원 2000 産業技術開發硏究 Vol.16 No.-

Exhaust pressure characteristics was described by change of exhaust manifold configurations in the exhaust system. Exhaust manifolds for analysis of exhaust pressure characteristics in this experiments were made and were single, double and conventional type of manifold. The pressure characteristics in the exhaust system were compared and analyzed according to exhaust manifold configurations, measuring positions, engine revolutions and loads. The results show that the peak pressure in exhaust system was decreased as the number of accessories in the exhaust manifold increased and the measuring position of sensor estranged from exhaust valve. And the accumulation of exhaust gas occurred in exhaust manifold was decreased by formulation of pulsating pressure wave than formulation of high pressure wave.

수종 수산화칼슘 Sealer의 근관폐쇄효과에 관한 전기화학적연구

신동훈,최국렬,홍찬의 大韓齒科保存學會 1995 Restorative Dentistry & Endodontics Vol.20 No.1

AbstractThe purpose of this electrochemical study was to determine and compare the sealing effect of three commonly used calcium hydroxide-based sealers (Sealapex, Apexit, and CRCS) with that of Roth 801 which is a ZOE-based sealer.64 single rooted teeth were used in this experiment. After removing the crown, the teeth were devided into 4 groups of 15 in each and obturated with gutta-percha and experi- mental sealers. 4 teeth were as controls(2 positive and 2 negative).The results were as follows : 1. During the observation period, all sealers showed varying degree of microleakage. 2. The mean leakage currents according to the electrochemical study of each group showed 0.418??0.006mV for Roth 801, 2.03??0.035mV for Sealapex, 3.33??0.069mV for Apxit and 6.48??0.097mV for CRCS group. The positive control group showed 600mV. 3. There were statistically significant difference in mean leakage among experimental groups. ZOE-typed Roth 801 sealer was the lowest, and Sealapex, Apexit, CRCS group in that order showed increased leakage (P<0.05). 4. Roth 801, Sealapex and Apexit group showed increasing leakage with time, but CRCS group showed stable or decreasing leakage tendency.

인터넷 광고효과에 관한 조사연구

이태로,최만규,임국환 高麗大學校 倂設 保健大學 保健科學硏究所 2003 保健科學論集 Vol.29 No.1

As internet becomes very important communication means for numerous people, a variety of advertisement are beginning to appear on the internet. People can get information about various things and do shopping via internet. This study was carried out to investigate the effect of internet advertisement on various groups. For this study, 200 people were surveyed. The results obtained were as follows: 1. Among the various advertisement types, since most people use e-mail and check e-mail very often, the advertisement through e-mail turned out the most effective advertisement means. 2. The type of advertisement using animation and moving pictures were preferred for most consumers. 3. As for the age groups, young people had the preference for the banner style and old age groups were interested in advertisements including free gift or discount events. 4. As for the favorite hours, the people in the twenties and the thirties preferred evening time(18:00 to 24:00) and people in the forties and fifties afternoon(12:00-18:00). 5. Male consumers showed preference (or the advertisement including free service programs and female consumers preferred the advertisement including discount programs or gifts.