• 한국정밀공학회지
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• 제23권10호
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• pp.74-79
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• 2006

In this study, the tempering effect on the wear characteristics of induction-hardened SPS5 steel was investigated. For this purpose, three tempering conditions were applied to control the hardness of heat-treated SPS5 steel. Ball-on-disk wear tests have been performed using zircornia balls on the tempered specimens to determine the variation of wear characteristics. The results showed that friction coefficient decreased with increasing hardness for induction hardening conditions. This seems to occur because real contact area between specimen and mating ball was affected by the specimen hardness.

• 대한기계학회논문집
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• 제13권6호
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• pp.1118-1127
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• 1989

본 연구에서는 두 치차사이의 접촉 문제를 해석하기 위하여 마찰을 고려한 수직 하중과 접선 하중이 동시에 작용하는 경우에서의 접촉 문제를 수식화하였다. 그리고 두개의 원통의 접촉으로 가정함이 없이 실제적인 인벌루우트 곡면간의 접촉 문제를 해석하기 위하여 유한 요소법을 사용하였으며 비선형 연립 방정식으로 수식화된 된 접촉 문제를 효과적으로 풀기 위하여 최적화 기법을 이용한 산법을 제시하였다. 이때 마찰을 고려한 치차의 접촉 문제 해석에 필요한 수직 압력 분포는 이 등에 의하여 이루어진 결과를 이용하였다. 제시한 산법에 의하여 마찰을 고려한 두 치차의 접촉 문제를 해석하여 치차 손상의 중요한 원인중의 하나인 피팅(pitting) 현상을 유발하는 실제적인 조건을 고려함으로써 자동화 및 정밀화 되어가는 기계의 중요한 부품으로서 치차의 정밀 설계를 하기 위한 정확한 자료를 제시하였다.

• 한국임상수의학회지
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• 제11권1호
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• pp.479-484
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• 1994

An English Bulldog 4 years old, Queen was hospitalized three weeks after mating as anorexia, decreased activity, hamorrhagic pus like vaginal discharge, and high fever. It was very difficult to diagnose by clinical signs and clinical pathological findings, at the first. Eenlarged uterus cavity, fluid accumulation in uterus was clearly identified by radiography and ultrasonography. The results suggest that X-ray and ultrasound is very important diagnostic method for pyometra to know disease progress.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집A
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• pp.731-736
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• 2000

An optimal design method is adopted for a spacer grid in nuclear power plant. It is made of punched sheet metal process, functioning as springs and dimples supporting fuel rods. For stress analysis of the assembled fuel rod support, a typical cell out of the repeated pattern in the assembly is modeled using 4-node shell elements. A commercial code, ABAQUS, is used for detailed analysis of contacting phenomena with friction. For the optimization, design varibles are taken from geometric parameters representing the shape of the bent leaf spring part and mating contact region with fuel rod. Objective function is considered in relation to mechanical functions and durability. Maximum yon Mises stress is considered in relation to constrained contact stress.

• 한국기계가공학회지
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• 제11권2호
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• pp.55-59
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• 2012

This study performs the bending and contact stress analyses for a pair of mating gears during rotation. The interested gears are used for a railway reducer. In general, the railway reducer needs high speed rotation, which leads to a large gear ratio. Thus, it is not easy to apply finite element method to investigate the strength performance, since the size of a gear is much larger than that of a pinion. In this study, the bending and contact stresses determined from FEM are compared with the values determined from the ISO code.

• 한국미생물·생명공학회지
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• 제22권6호
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• pp.584-592
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• 1994

Several mutation procedures have been compared to obtain an ethanol-tolerant Saccha- romyces diastaticus strain secreting glucoamylase. These procedures include spontaneous mutation, EMS treatment, UV irradiation, and combination of EMS treatment and UV irradiation. All these methods were followed by adaptation of the yeast cells to gradually higher ethanol concentration. Among these procedures, the combined method of EMS treatment and UV irradiation gave the promising result, i.e. the ethanol tolerance of the yeast increased from 11.5%(v/v) to 14.0%(v/v). Respiratory deficient petite mutants of industrial and ethanol-tolerant yeast strains have been isola- ted and hybridized with haploid S. diastaticus strains. The resulting hybrids showed increased ethanol tolerance and starch-fermentability.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.409-410
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• 2006

In this study, the tempering effect on the wear characteristics of induction-hardened SPS5 steel was investigated. For this purpose, three tempering conditions were applied to control the hardness of heat-treated SPS5 steel. Ball-on-disk wear tests have been performed using zircornia balls on the tempered specimens to determine the variation of wear characteristics. The results showed that friction coefficient decreased with increasing hardness for induction hardening conditions. This seems to occur because real contact area between specimen and mating ball was affected by the specimen hardness.

• 대한핵의학회지
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• 제35권4호
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• pp.224-230
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• 2001

EBM is "the conscientious, explicit and judicious use of current best evidence in mating decisions about the care of the individual patient. It means integrating individual clinical expertise with the best available external clinical evidence from systematic research." EBM is the integration of clinical expertise, patient values, and the best evidence into the decision making process for patient care. The practice of EBM is usually triggered by patient encounters which generate questions about the effects of therapy, the utility of diagnostic tests, the prognosis of diseases, or the etiology of disorders. The best evidence is usually found in clinically relevant research that has been conducted using sound methodology. Evidence-based medicine requires new skills of the clinician, including efficient literature-searching, and the application of formal rules of evidence in evaluating the clinical literature. Evidence-based medicine converts the abstract exercise of reading and appraising the literature into the pragmatic process of using the literature to benefit individual patients while simultaneously expanding the clinician's knowledge base. This review will briefly discuss about concepts of evidence medicine and method of critical appraisal of literatures.

• 미생물학회지
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• 제28권3호
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• pp.188-191
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• 1990

The streptococcal plasmid pAM$\beta_{1}$ (erythromycin resistance)was transferred via conjugation from Streptococcus faecalis DS 5 to Lactobacillus casei YIT 9018 by a filter mating method. The transfer frequency depended greatly on the type, pore size and side(front or back) of membrane filter. Water passing through a membrane under reduced pressure induced very tight contact between the cells, increased the transconjugation frequency about 1.3 to 37-fold when Millipore membrane filter (0.45.$\mu$m, front side up) was used.

• 소음진동
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• 제10권1호
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• pp.107-116
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• 2000

The gear whine noise caused by tooth profile, elastic deformation, machining error, wear is directly correlated with the transmission error of mating gear. It is very important to build up the synthesized countermeasure by the modeling of the excitation forces and analyzing the vibratory characteristics. The mathematical models on the elements of vehicle transmission which is composed of helical gears, bearings, shafts and cases are developed. The elements are assembled by the substructure synthesis method. The cases of transmission are modeled by ANSYS. The system model of vehicle transmission is also verified by the experiments.