http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
이동우,홍순혁,조석수,주원식,Lee, Dong-U,Hong, Sun-Hyeok,Jo, Seok-Su,Ju, Won-Sik 대한기계학회 2002 大韓機械學會論文集A Vol.26 No.9
Fatigue fracture in machine components is produced by surface micro-crack from stress concentration area such as notch and material defect. It is difficult to predict the remaining fatigue lift of mechanical components because the surface micro-crack on critical area initiates and grows with statistical distribution. Plane bending fatigue tests were carried out on the plain specimen of Al 2024-T3 and the initiation and growth behavior of surface micro cracks were observed. The statistical distribution of surface length of multiple micro cracks and their maximum length were investigated. The maximum surface crack length distributions were analyzed on the basis of the statistics of extremes in order to examine the prediction of remaining life.
실험계획법과 수리적방법을 이용한 이산설계 공간에서의 다목적 최적설계
이동우,백석흠,이경영,조석수,주원식,Lee, Dong-Woo,Baek, Seok-Heum,Lee, Kyoung-Young,Cho, Seok-Swoo,Joo, Won-Sik 대한기계학회 2002 大韓機械學會論文集A Vol.26 No.10
A recent research and development has the requirement for the optimization to shorten design time of modified or new product model and to obtain more precise engineering solution. General optimization problem must consider many conflicted objective functions simultaneously. Multi-objective optimization treats the multiple objective functions and constraints with design change. But, real engineering problem doesn't describe accurate constraint and objective function owing to the limit of representation. Therefore this study applies variance analysis on the basis of structure analysis and DOE to the vertical roller mill fur portland cement and proposed statistical design model to evaluate the effect of structural modification with design change by performing practical multi-objective optimization considering mass, stress and deflection.
소아 환아에서 분리된 Vancomycin 내성 장구균에 대한 임상적 고찰
이동우,이경재,장광천,김동수,이경원,박은숙,Lee, Dong Woo,Lee, Kyung Jae,Jang, Gwang Choen,Kim, Dong Soo,Lee, Kyung Won,Park, Eun Suk 대한소아감염학회 2001 Pediatric Infection and Vaccine Vol.8 No.2
목 적 : 1986년 vancomycin 내성 장구균(이하 VRE)이 보고된 이후 10여년간 빈도는 급격한 증가 추세에 있다. 이에 저자 등은 본 병원에 입원한 소아환자들의 임상검체에서 분리된 VRE의 양상과 해당 환자들의 사용형태에 대한 조사를 시행하여 VRE의 증가양상에 적절히 대처할 수 있는 방안을 모색하고자 본 연구를 시행하였다. 방 법 : 1998년 1월부터 2000년 12월까지 연세의료원 세브란스병원에 입원한 소아 환자에서 분리된 VRE 36주를 대상으로 하여 검체 종류 및 균종, 항균제 감수성과 사용양상을 조사하였고, ICU 환자군과 Non ICU 환자군으로 분류하여 두 군간에 있어서 수술이나 중재적 시술을 시행한 경우와 내과적인 투약처치만을 시행한 경우 등의 분리 전 처치형태를 조사하였고 항균제 감수성을 파악하였으며 중복감염의 여부가 ICU군과 Non ICU군간에서 차이를 보이는지 조사하였다. 결 과 : 본 연구에서, VRE가 분리된 수가 급속히 증가함을 알 수 있었고, ICU 환아군과 수술이나 중재적 시술을 한 경우에서 높은 빈도를 보였으며, E. faecium이 E. faecalis 보다 많이 분리되었다. VRE 항균제 감수성 검사에서 tetracyclin을 제외한 항생제에 높은 내성을 지니고 있었고, 검출된 cephalosporin의 투여비율이 가장 높았으며 검출 후에는 teicoplanin의 투여비율이 증가함을 볼 수 있었고, teicoplanin에 대한 항균제 감수성 결과에 따른 투여비율의 차이는 없었다. 또한, ICU 환자군이 Non ICU 환자군에 비해 중복감염의 경우가 많았다. 결 론 : 증가하고 있는 VRE의 집단 발생과 전파에 이은 합병증을 막기 위해서, 본 연구에서 ICU 단위로 분류하였던 병동과 같은 병원내 VRE의 상재 위험지역에 대한 집중 감시조사와 이의 관리를 위한 여러 행정적 문제의 해결, 적절한 항생제의 사용과 철저한 관리가 필요하리라 사료된다. Purpose : Since the first report of vancomycin-resistant enterococci(VRE) in 1986, the resistance to vancomycin in enterococci has been increasingly rapidly. In this study, we investigated the clinical manifestations of pediatric patients with VRE and the pattern of the antibiotic use with increasing the rate of VRE in pediatrics Methods : We studied retrospectively 36 pediatric patients who were isolated VRE from January 1998 to December 2000. We classified patients into ICU and non ICU groups and reviewed species of VRE, specimens in which VRE were first detected and procedures performed before VRE detected. Results : We have found that the number of pediatric patients isolated VRE is increasingly annually in this study. In addition, the number of VRE-isolation in the ICU group and in patients who were operated or who underwent active procedures is much higher than that of in the non ICU group and in patients who were taken medication only. Enterococcus faecium is the main species of VRE. VRE showed high resistance to almost all antibiotics except tetracycline, and resistance was closely related to the duration of hospitalization and history of the antibiotic use. The proportion of the cephalosporin use was higher than any other antibiotic before VRE detection. In contrast, that of teicoplanin was higher than any other antibiotic after VRE detection(P<0.05). The cases of superinfection is higher in the ICU group than in non ICU group. Conclusion : In the hospital level, prevention of nosocomial infection through proper administrative policies, through surveillance of high risk VRE regions and prudent antibiotic use can prevent VRE outbreaks and corresponding side effects.
이동우(Dong Woo Lee),홍순혁(Soon Hyeok Hong),이경영(Kyoung Young Lee),조석수(Seok Swoo Cho),주원식(Won Sik Joo) 대한기계학회 2003 대한기계학회 춘추학술대회 Vol.2003 No.4
The vertical roller mill is the important machine grinding and mixing various crude materials in the manufacturing process of portland cement. Table liner is one of grinding elements of vertical roller mill and is subjected to the eyelic bending stress by rollers load and the centrifugal foree by rotation of table. It demands 4×10^7 cycle but has 4×10^6 clcle. It fractures at the edgc of grinding path of outside roller. The repair expense for it amounts to 30% of total maintenance of vertical toller mill. Therefore, this study shows the racture mechunism of teble liner for vertical roller mill using HDM and latigue analysis.