非線形 理論에 依한 채터 解析

이형식,정준기,박태형 연세대학교 산업기술연구소 1983 논문집 Vol.15 No.2

The chatter analysis has been studied by many authors using non-linear. In this study, the stability chart obtained from experimental work with a lathe was qualitatively compared with the result of chatter analysis by non-linear theory. Experimental results verify that the stability of the machining process is affected by the width of cut in the following manner. As the chip width is increased from zero with the rotational speed of the workpiece kept constant, three ranges are distinguished; (a) unconditionally stable range, (b) conditionally stable range, (c) unstable range. In the conditionally stable range the system is stable for small disturbances but unstable when these exceed a certain level. When the chatter occurs, the amplitude initially increases and stabilizes itself at a finite level. This phenomenon agrees well with the analysis of non-linear theory qualitatively.

Centerless Feeder 장치의 개발

강형모,권경우,김기길,정의식,허영환 한밭대학교 산업과학기술연구소 1994 논문집 Vol.2 No.-

This paper presents results of the development of centerless feeding system which are applicable to bearing metal processes. As a result, the feeding system can be applied to automatic surface finishing on the bearing metal process such as bush, and has greatly effects on the increase of the prodnctiving and the decrease of the man power an effect on increase the productivity and decrease the man power and effect on increase the productivity and decrease the man power of the bush machining process.

댐퍼붙이 거위목바이트를 使用하는 切削系의 動的 安定性에 關한 硏究

李炯植,鄭準基,盧光春 연세대학교 산업기술연구소 1982 논문집 Vol.14 No.2

The effect of the damped goose-neck tool upon the dynamic stability of machine tool was investigated. The dynamic stability of machine tool is directly related to the chatter in the metal cutting process. By the test of the dynamic characteristics for the damped goose-neck tool, theoretical approach of dynamic stability of machine tool is identified. It's results are compared with the results of actual cutting test. And the dynamic stability of machine tool is improved by the higher elasticity and the increase of damping coefficient for the damped goose-neck tool.

누두흉 환자에서 Nuss 금속막대 제거 전 · 후 폐 역학 변화

강규식,백남순,김천숙,안기량,권진형,김지은,유시현 순천향의학연구소 2003 Journal of Soonchunhyang Medical Science Vol.9 No.1

Nuss operation is one of the surgical procedure for pectus excavatum and it's method is the insertion of convex steel bar under the sternum through small bilateral thoracic incision. As the patients is growing, the thorax can be compressed gradually by steel bar. So Nuss bar needs to be removed two years after Nuss operation. This study was undertaken to assess the effect on the repiratory mechanics before and after the removal of the Nuss bar. Twenty patients with previous Nuss operation were allocated for the removal of Nuss bar. Lung mechanics (dynamic lung compliance, static lung compliance, and airway resistance), hemodynamic change (heart rate, systolic pressure, and diastolic pressure), and pulmonary gas exchange (arterial oxygen tension, arterial carbon dioxide tension, pulse oximeter saturation, and end tidal carbon dioxide tension) were measured before and after removal of Nuss bar. Respiratory mechanics (dynamic and static lung compliance, inspiratory airway resistance), pulmonary gas exchange and hemodynamic parameter were unchanged before and after the removal of Nuss bar. We concluded that lung mechanics were not changed before and after the removal of Nuss bar in the patients with pectus excavatum and the 95% patients were satisfied with operation.

한의진단명과 진단요건의 표준화 연구 III : 3차년도 연구결과 보고

최선미,양기상,최승훈,박경모,박종현,심범상,김성우,노석선,이인선,정진홍,이진용,김달래,임형호,김윤범,박성식,송태원,김종우,이승기,최윤정,신순식 한국한의학연구원 1997 한국한의학연구원논문집 Vol.3 No.1

The diagnostic requirements were suggested and explained regarding the systems of differentiation of symptoms and signs in the third year study of standardization and unification of the terms and conditions used for diagnosis in oriental medicine. The systems were as follows : - analyzing and differentiating of epidemic febrile disease - analyzing and differentiating in accordance with the Sasang constitution medicine based on four-type recognition - differentiation of disease according to pathological changes of Chong and Ren channels - standards for diagnosis of women's disease - standards for diagnosis of children's disease - standards for diagnosis of motor and sensor disturbance (-muscle. born, joint, etc.) - standards for diagnosis of neuropsychiatric disease - standards for diagnosis of five sense organ disease - standards for diagnosis of external disease The indivisual diagnosis pattern was arranged by the diagnostic requirements in the following order : another name, notion of diagnosis pattern, index of differentiation of symptoms and signs, the main point of diagnosis, analysis of diagnosis pattern, discrimination of diagnosis pattern, prognosis, a way of curing a disease, prescription, herbs in common use, disease appearing the diagnosis pattern, documents. The standards for diagnosis of each disease was arranged by the diagnostic requirements in the following order : another name, notion of disease, the main point of diagnosis, analyzing and differentiating of disease, analysis of disease, discrimination of disease, prognosis, a way of curing and prescription of disease, disease in western medicine appearing the disease in oriental medicine, documents.

다발성 대장암 간전이 환자의 간절제를 위한 새로운 시도

주종우,김형철,임철완,신응진,조규석,유기원,송옥평,홍대식,박성진,조준희,이혜경,김희경,권계원,고은석 순천향의학연구소;Soonchunhyang Medical Research Institute 2004 Journal of Soonchunhyang Medical Science Vol.10 No.2

Multiple bilobar liver matastases (MBLM) are the main cause of low resectability in the colon cancer liver metastases. The authors experienced one case of initially non-resectable colon cancer liver metastases. He was curatively and safely treated with a two-stage hepatectomy using the new method of future remnant liver volume growing. A 54-year-old man was referred to our department with the sigmoid colon cancer combined with MBLM, which were checked in two small metastatic lesions in the left lobe and five large sized lesions in the right lobe in the computed tomogram (CT). A laparoscopic assisted anterior resection was primarily performed. We performed the 1^(st) stage hepatectomy 3 weeks after the colon resection. Intra-operative Ultrasonogram (US) found 9 small superficial metastatic lesions in the left lobe. All that lesions were completely removed by non-anatomical wedge resection. An occlusion ballon catheter was placed in the right portal vein through a small branch of the inferior mesenteric vein at that time. The future remnant liver volume was sufficiently increased 3 weeks after the 1^(st) hepatectomy. A right hepatectomy was safely performed 22 days after the 1^(st) hepatectomy. The patient received a regional chemotherapy (interleukin2 based immuno-chemotherapy through hepatic artery) for 4 months, then received 9 cycles of systemic chemotherapy (biweekly Oxaliplation, leucovorin, plus 5-fluorouracil) without any recurrence evidence.

고유 불안정한 도립진자 시스템의 최적 안정화 제어에 관한 연구

최부귀,박영식,안기형,이취중 동아대학교 공과대학 부설 한국자원개발연구소 1990 硏究報告 Vol.14 No.1

This paper proposes a design techinque of dynamic stabilization controller for the intrinsic unstable inverted pendulum system. Mathematical modelling with the more complex nonlineaity and the stabilized control theory presented by C.D. Johnson are adapted to this system by using the stage-space approach. And the stabilized controller with the designed optimal regulator type which can be fastly tracked and can be accurately counteracted against all effects of the constant disturbances and the parameteric variations is sumulated and is implemented successfully on the microcomputer.

敎科課程을 中心으로 한 韓日農學系(園藝·食品·獸醫)大學의 敎育現況 調査

李愚升,孫泰華,尹衡植,毛麒喆 경북대학교 1982 새마을 硏究論叢 Vol.2 No.-

The authors studied on the curicullum between Korea and Japan in the deaprtments of horiculture, food technology and veterinary. The results are as follows. 1. In the department of horticulture, professional education period was 3 years in Korea while 2 or 2.5 years in Japan. These results were compared among 3 colleges of Korea and Japan. Credits for graduation was 48-52% for propessional education with submajoring subjects and 45% when majoring subject in Korea, but 54-61% in Japan. Credits for required subjects were 17-29% among credits for graduation in Korea while 28-29% in Japan. 2. Cultural education period is almost 1 year in Korea, but different in Japan. Credits for graduation are as follows; Cultural education is 36-37%, majoring fields 15% and the others 12-13% in Korea while 43-46% for cultural education, 54-57% for majoring field in Japan. Differences were shown among 3 colleges dealt with the department of food technology by locational characteristics in Japan. 3. In the department of Veterinary, collage curicullums were not fixed for the students because of transitional period. Required subjects among 4 colleges were shown as the same tendency in Korea.

골격성 Ⅱ급 부정교합자의 악교정 수술 후 설골의 위치와 상기도 변화에 관한 연구

배진성,김경호,박형식,허종기,박광호 大韓顎顔面成形再建外科學會 2001 Maxillofacial Plastic Reconstructive Surgery Vol.23 No.6

OSAS(obstructive sleep apnea syndrome) is becoming more and more of importance nowadays. Therefore the study concerning OSAS is very important. Most of the studies which have been reported were comparison of upper airway size and change of skeletal class Ⅰ group and skeletal class Ⅲ group respectively. But, most of the showing OSAS have pharyngeal narrowing combined with more or less distinct maxillary and mandibular deficiency. Therefore the aim of this study is to see posterior airway space and hyoid bone position in patients affected by class Ⅱ malocclusion and treated with orthognathic surgery. we measured the lines between selected upper air way landmarks on lateral cephalometric x-ray films of skeletal class Ⅱ 30 persons who had not been operated yet, were within 2 weeks after operation, were 6 months after operation. And we compared them respectively and analyzed them with pairing t-test, pearson correlation coefficient and multiple regression analysis. The results were as follows. First of all, skeletal class Ⅱ group was increased in all the level of PAS, especially PAS(MK) and PAS related to hyoid bone(H-phW, H-PhW(Me-H)) was significantly decreased within 6 months after operation but that was larger than preoperation. And then the PAS was increased after mandibular advancement surgery. While there was no significant correlation between PAS and surgical methods, there was statistical significance between PAS and a number of surgical movement. At last, the hyoid bone was advanced within 2 weeks after operation but relapsed within the follow up period. In the end of the study, it was turned out that PAS was always wider without distinction of the region after the operation and that there was significant correlation between the moving volume of hard tissues and the changing quantity of PAS( ; how much PAS was changed according to the moving degree of hard tissues). After this, to be based on the study, I consider that OSAS demands further study and that it is necessary to do more practical applications to the patients.

A2024와 SM45C 마찰용접의 열전달 해석

이상윤,고준빈,명태식,김기길,강형모 大田産業大學校 2001 한밭대학교 논문집 Vol.18 No.-

The heat transfer mechanism initiating the friction welding is examined and a transient three dimensional heat conduction model for the welding of two dissimilar cylindrical metal bars is investigated. The cylindrical metal bars are made of materials made of A2024 and SM45C. Numerical simulations of heat flow are performed using the finite volume method. Respectively, Commercial FLUENT code is used in the heat flow simulation and maximum temperature and distribution of temperature are calculated. Temperature of friction welded joining face is compared with the temperature distribution measured by experiment and numerical simulation. The maximum temperature of friction welded joining face is lower than melting point of A2024-T6 aluminum alloy using insert metal. The temperature distribution of friction welded joining face with insert metal is more uniform than that of without insert metal