초고속 치과용 핸드피스 개발

한명철,김정관,최명욱,이왕근,김헌주 한국공작기계학회 2008 한국공작기계학회 춘계학술대회논문집 Vol.2008 No.-

The dental high-speed handpiece is one of the most popular and important devices that has been widely used as the main means of cutting tooth structure and restorative materials in dentistry, In consideration of usage and marketability of the dental handpiece, it is obviously worthy of investigating it. In this paper, a high speed dendal handpiece is developed through reverse engineering with 3D X-Ray CT equipment and wire cutter for the Mark II model in NSK. The demension of the handpiece parts is obtained through this process, and 3D modeling is performed with CATIA V5. The interference between parts can be examined through the part assembly in CATIA, and the performance is finally compared with Mark II model in NSK.

일부 생산직 근로자의 소음과 사회심리적 요인이 혈압에 미치는 영향

박종구,강명근,차봉석,고상열,장세진,고상백 大韓産業醫學會 1997 대한직업환경의학회지 Vol.9 No.2

This study was conducted to assess the effects of noise exposure and psychosocial factor on blood pressure in manufacturing workers. The study subjects are 414 workers(243 males, 171 females) employed at the noisy department. The mean age of low exposed group(<85dB) was 34.65±9.53 years, and that of high exposed group(≥85dB) was 36.37±11.15 years. The difference in mean age was not significant. The mean and distribution of working duration, smoking status, drinking status were not significantly different between two groups. The mean systolic blood pressure of the low exposed group was 120.01±12.06 mmHg, and that of high exposed group was 126.27±13.84mmHg. The mean diastolic blood pressure of the low exposed and the high exposed group were 77.18±10.83 mmHg, and 83.46±11.22mmHg respectively. These differences of blood pressure were statistically significant(p<0.05). The workers in noisy department have significantly less work environmental satisfaction, higher job demand, and higher social support. The mean values of psychosocial distress were higher in the workers of the noisy department, but the difference was not statistically significant. This study was to speculate whether the work environmental satisfaction and social support modify the association between the noise exposure level and the blood pressure. The result showed that work environmental satisfaction could not modify the association between the blood pressure and the noise exposure. Social support at work did not modify the association. Furthermore, we evaluated the high job strain from a combination of ratio of the high job strain group for hypertension in diastolic blood pressure were statistically significant, but not in systolic blood pressure. Hierarchical multiple regression analysis was used to determine whither the independent variables contributed to explaining the blood pressure. After controlling for possible confounders, we found that the noise exposure level was a correlated of the diastolic blood pressure. But no association between the noise exposure level and the systolic blood pressure. No significant result was found for psychosocial factor.

POPS 네트워크 구조에서의 Bitonic 정렬 알고리즘에 관한 연구

鄭均樂,宋命根 弘益大學校 科學技術硏究所 2001 科學技術硏究論文集 Vol.12 No.-

The partitioned optical passive stars network (POPS) is an optical interconnection network for a multiprocessor computer. It uses multiple OPS couplers which can receive an optical signal from any one of its source nodes and transmit the received signal to all of its destination nodes. A message can be sent from one processor to the other in a single slot. A POPS(d, g) network partitions the n processors into g groups of size d and the choice of g and d affects the interconnection cost and the bandwidth. Sorting is one of the most important operations performed by a computer and many parallel sorting algorithms have been investigated for various parallel computer architectures. In this paper, we have studied how to implement efficiently the bitonic sort on a POPS network.

직업적 관현악 연주자의 근골격계 증상 유병률과 관련요인

김성수,박종,류소연,강명근,홍강식 朝鮮大學校 統計硏究所 2007 統計硏究所論文誌 Vol.9 No.1

Objectives: This study was performed to find out the prevalence and factors that are related to the musculoskeletal disorders. Methods:Questionnaire were distributed from September 15th to 30th. 2000 to 156 musicians in two orchestras in Gwangju and Chonnam areas. Results: Considering a symptom prevalence of the musculoskeletal system, 97 (92.4%) string musicians. 17 (56.7%) woodwind musical instruments, and (100.0%) brass musicians have symptoms. The result of stepwise multiple logistic regression analysis. those who stretch before practice have 0.09 times (95% confidence interval : 0.01-0.66) less risk of symptoms than those who do not. Those who practice daily for three hours have 0.08 times (95% confidence interval : 0.01-0.71) less risk of symptoms than those who practice for two hours a day. Those who has stress at work have 2.66 times (95% confidence interval : 1.36-119.83) as many symptoms as those who has little stress. Those who have much stress at work has 64.19 times (95% confidence interval : 6.22-598.73) as many symptoms as those who have little stress at work. Those who answered that they would join the company again have 0.06 times (95% confidence interval : 0.02-0.17) less risk of symptoms than those who answered that they do not want to join the company again. Conclusion: The various factors have an effect on symptoms of the musculoskeletal systems among musicians of professional orchestras. It is considered that job-related factors such as stretching before practice, personal practice hours and satisfaction and stress at work are the related factors of systems.

일부 의과대학생의 음주 실태와 관련 요인

류소연,윤혜은,김기순,박종,강명근,박계남 朝鮮大學校 附設 醫學硏究所 2004 The Medical Journal of Chosun University Vol.29 No.2

Objectives : This study was performed to investigate the drinking status and the related factors with problem drinking in some medical students. Methods : The study subjects were 345 premedical students (freshmen and sophomore) and medical students (sophomore) in a medical school who replied to the self-administered questionnaire survey during March 2002. The questionnaire was composed of general characteristics, drinking status, social value about drinking, health status, satisfaction of life and alcohol use disorders identification test (AUDIT) . Results : The experience rate of drinking was 88.8% in male and 88.3% in female and it was tended to increase with going up the grade. Prevalence of hazardous, dependence, harmful and problem drinking classified by AUDIT score criteria were 66.2%, 3.0%, 7.0% and 5.1% in male and 34.9%, 0.9%, 1.9%, 1.9% in female. In male, the statistically significant related factors to Al JDIT scores were grade, religion, maternal drinking status, social value about drinking, affectionate feelings of those around one and satisfaction of life. Only social value about drinking was statistically significant correlated factor with AUDIT scores in female. As a result of multiple regression analysis, the related factors with AUDIT scores were sex, maternal drinking status, satisfaction of life and social value a bout drinking. Conclusion : The experience rate of drinking in medical students was higher than that in other college students. Grade, family drinking history, negative psychological feelings, social value about drinking were risk factors to problem drinking.

초소형 쎄레이션 볼트의 체결성능 분석

장명근(Myung Guen Jang),정진환(Jin Hwan Jeong),장연희(Yeon Hui Jang),김희철(Hee Cheol Kim),김종봉(Jong-Bong Kim) 대한기계학회 2017 大韓機械學會論文集A Vol.41 No.4

최근 스마트 폰, 스마트 와치 등과 같은 전자기기의 크기가 작아지면서, 그에 사용되는 체결 볼트의 크기 또한 작아지고 있다. 초소형 나사는 제품을 체결하는 데 있어 충분한 체결 토크나 풀림 방지효과를 갖지 못한다. 그래서 초소형 나사의 체결력과 풀림방지 효과를 유지 및 강화하는 연구가 필요하다. 본 연구에서는 초소형 나사의 풀림방지 효과를 강화하기 위해 나사의 머리 밑 면에 쎄레이션 형상을 추가하여 그 효과를 분석하였다. 쎄레이션 볼트는 풀림과정에서 피체결체 윗면을 변형시켜 풀림 방지 턱을 생성해 풀림을 방지하는 역할을 한다. 쎄레이션 개수와 체결 깊이를 변수로 하여 그 영향을 분석하고 풀림 방지 성능에 미치는 영향을 확인하였다. As the size of electric products such as mobile phones and smart watches decrease, the bolts used to assemble these products should also be miniaturized. A miniature-sized bolt has to provide sufficient joining torque and anti-releasing torque to keep the components together. We studied a serrated bolt as a candidate for a miniature-sized fastener to increase the anti-releasing torque. In a serrated bolt, a serrated shape is formed on the bottom surface of the bolt head to create an obstacle to releasing. In this study, finite element analyses for the joining and releasing of bolts were carried out, and the anti-releasing performance was predicted. Based on the results of analyses using various numbers of serrations and fastening depths, the effects of the number of serrations and fastening depth on the anti-releasing performance were investigated.

혈액투석중인 만성신부전 환자에서 혈압조절의 양상과 투석적절도가 혈압에 미치는 영향

김명빈(Myung Bin Kim),박규용(Ky Yong Park),김근호(Guen Ho Kim),전노원(Rho Won Chun),김형직(Hyung Jik Kim),채동완(Dong Wan Chae),노정우(Jung Woo Noh),구자룡(Ja Ryong Koo) 대한내과학회 1999 대한내과학회지 Vol.56 No.5

N/A Objective : Volume expansion has been known to be the major factor in the development of hypertenision in chronic hemodialysis(HD) patients. But some HD patients remain hypertensive even with adequate volume control, which suggests the role of undefined uremic toxin in the pathogenesis of hypertension. So we aimed to evaluate the status of blood pressure (BP) control and the effect of Kt/V (as a marker for removal of uremic toxin) on BP in chronic HD patients. Methods : The status of BP control was obtained from records of 8 HD session in 132 patients in November 1996 and 127 patients in November 1997. Of 132 patients studied in 1996, 70 patients underwent a follow-up evaluation in 1997. All patients were dialyzed 3 times a week, 4 hours a session. Postdialytic cyclic 3',5' guanosine monophosphate (cGMP) level was measured in 48 patients as a marker of volume status. Results : The prevalence of postdialytic hypertension (>140/90mmHg) was 73.5 in 1996 and 65.3% in 1997. Normotensive patients (postdialytic mean BP <114 mmHg) had higher Kt/V value than hypertensive patients in both 1996 and 1997. But there was no difference in the degree of ultrafiltration (UF) and cGMP level between two groups. Postdialytic mean BP was inversely correlated with Kt/V level but had no relationship with degree of UF and cGMP level in both 1996 and 1997. The group in which postdialytic mean BP had been decreased during 1 year study period had higher degree of elevation in Kt/V than the group in which postdialytic mean BP had been increased. The changes of postdialytic weight and degree of UF during study period were similar between two groups. The number of antihypertensives used were also inversely correlated with Kt/V but not correlated with degree of UF and cGMP level in both 1996 and 1997. Conclusion : Our study indicate that increasing HD adequacy is associated with improved control of postdialytic mean BP and less use of antihypertensive drugs. UF and antihypertensive drugs may not be adequate form of hypertension treatment as once thought and increasing HD adequacy can be an alternative method.

Wide Range Laser tuning using Incomplete Energy Transfer in Cholesteric Liquid Crystal Structure

Mu Guen Chee,Myung Hoon Song,In Jae Chung Jung 한국고분자학회 2006 한국고분자학회 학술대회 연구논문 초록집 Vol.2006 No.10

SF-36을 이용한 근로자들의 건강수준 평가

강명근,박종구,장세진,고상백,차봉석 大韓産業醫學會 1998 대한직업환경의학회지 Vol.10 No.1

This study was conducted to understand health status by general characteristic, and to find out relationship between social support and worker's health status. Health status was measured using SF-36(Medical Outcome Study Short Form 36), a 36 item self administered instrument. The finding of this study were as follow; Mean scores of health status by sex were higher in male. The younger worker reported good health on physical functioning and role limitation-physical than did the older worker, but the older worker reported good health on social functioning and mental health. Mean scores of health status were higher in high income and white worker. When the relationship between social support and health status, social functioning, role limitation-emotion, mental health, vitality, general health were significantly related. Therefore we reviewed the evidence that socio-economic condition are associated with health status in this study, and that the strength of the social support was a important to maintain health.

包括贈與擬制規定의 違憲性 遡考 : 상속세 및 증여세법 제42조를 중심으로

崔明根 세법연구회 1997 조세법연구 Vol.3 No.-