반경하중을 받고있는 결함 볼베어링의 진동분석

강병용,이우섭,장호경,김예현,Kang, Byoung-Yong,Lee, Woo-Seop,Chang, Ho-Gyeong,Kim, Ye-Hyun 한국음향학회 1997 韓國音響學會誌 Vol.16 No.4

본 연구에서는 빈경하중과 축회전 속도를 변화시켜 가며 하중으로 인한 베어링의 부하-변위량 특성을 Harris 이론과 비교분석하였다. 실험결과 결함이 없는 경우 하중이 적을 때는 Harris이론과 비교적 잘 일치하나, 하중이 증가할 수록 구동축의 변곡, 볼베어링 하중의 불균형 등의 영향을 받아 이론값과 차이를 보였다. 반경방향 하중이 있는 단일결함과 다중결함의 경우 하중이 증가함에 따라 변위량의 변화는 축심변위량 보다 반경변위량이 더욱 커지게 된다는 것을 알았다. 베어링의 결함상태에 따라 하중과 변위량의 기울기인 부하-변위량 특성을 구함으로써 볼베어링의 결함유무를 검출하였다. In this study, comparison between Harris-theoretical values and experimental data of load-deflection characteristics in bearing was made. The experiments are conducted under the conditions of the various radial loads and speed of shaft. In the case of non-defective ball bearing, the experimental data agreed well with the Harris-theoretical values for the small steady radial load but not for the large steady radial load. For the radial load bearing, the experimental results show that the stiffness of bearing at the single and multiple defective bearing are bigger in the radial defectiion than in the axial deflection. Load-deflection characteristics for the bearing defect part make it possible to detect the presence of a defect in bearing.

Genetic Polymorphisms of t-PA and PAI-1 Genes in the Korean Population

강병용,Kang Oh Lee 한국통합생물학회 2003 Animal cells and systems Vol.7 No.3

Abnormalities in fibrinolysis system is associated with risk of hypertension. In this report, the Alu repeat insertion / deletion (I / D) polymorphism of tissue plasminogen activator (t-PA) and the Hind III RFLP of plasminogen activator inhibitor-1 (PAI-1) genes were investigated in 115 normotensives and 83 patients with hypertension, and their association with anthropometrical data and plasma biochemical parameters were analyzed. There were no significant differences in the gene frequencies of the two candidate genes between normotensives and hypertensives, respectively. Our results indicate lack of associations between the two polymorphisms in t-PA and PAI-1 genes and risk of hypertension in the population under study. However, the Hind III RFLP of PAI-1 gene was significantly associated with plasma glucose level, suggesting its role in glucose metabolism. It needs to be tested whether this RFLP of PAI-1 gene is associated with insulin resistance syndrome or non-insulin dependent diabetes mellitus (NIDDM) in the Korean population.

The Mitochondrial DNA 5178 A/C Polymorphism inElite Korean Male Athletes

강병용,강친양,김재현,김기태,이강오 한국유전학회 2003 Genes & Genomics Vol.25 No.3

In view of the important role of human mitochondrial DNA (mtDNA) as candidate for athletic performance, we investigate the mt5179=8 A/C polymorphism of the mtDNA in the elite Korean male athletes and sedentary male controls. Total genomic DNA was isolated from 100 elite Korean male athletes and 64 sedentary male controls. The mt 5178 A/C polymorphism was analyzed by polymerase chain reaction (PCR) and Alu I restriction fragment length polymorphism (RFLP) method. This polymorphism was not significantly associated with Vo2max index in elite male athletes under this study. However, the excess of A allele in marathon runners was also observed among our sporting disciplines, although no statistical significance. Further studies using larger sample size wlill be required to clarify the relatihiionship between this genetic variation of mtDNA and athletic performance

Genetic Analysis of Kallikrein-Kinin System in the Korean Hypertensives

강병용,배준설,Kang Oh Lee 한국통합생물학회 2004 Animal cells and systems Vol.8 No.1

The kallikrein-kinin system affects regulation of blood pressure, and genes encoding for the components of this system have been considered as good candidates for hypertension. To evaluate the relationship between genetic polymorphisms of candidate genes involved in this system and hypertension, we performed case-control studies using genetic markers in Korean normotensives and hypertensives, respectively. By association study, there was a marginal association with hypertension in AA genotype distribution of A1789G polymorphism in the hKLK1 gene (P = 0.0754). Thus, this genetic polymorphism may weakly contribute to the susceptibility to hypertension in Koreans. We also observed that significant linkage disequilibrium exists among three polymorphic sites in the hKLK1 gene studied, suggesting that the three genetic polymorphisms can be useful as genetic markers in clinical association studies. Further studies using larger sample sizes and more genetic markers will be needed to clarify genetic influence of kallikrein-kinin system for hypertension.

ATM 수요 분석 및 예측

강병용 한국통신학회 1994 한국통신학회 워크샵 Vol.- No.-

선박 대기오염물질 배출량 현황 조사 및 관리대책 방안

강병용,홍승기,이승환,정봉훈,구자영 해양환경안전학회 2019 해양환경안전학회 학술발표대회 논문집 Vol.2019 No.11

Association Study Between Vitamin D Receptor Gene Polymorphism and Adult Periodontitis in Korean

강병용,하남주 한국통합생물학회 2003 Animal cells and systems Vol.7 No.2

Adult periodontitis is a chronic inflammatory disease whose etiology is not well defined. Recent studies have shown that vitamin D receptor gene has been a candidate for the susceptibility of adult periodontitis. The purpose of this study is to investigate the frequency of Taq I restriction fragment length polymorphism (RFLP) in the vitamin D receptor gene in 141 periodontically healthy controls and 28 adult periodontitis patients. Taq I RFLP in the vitamin D receptor gene was detected by PCR amplification, followed by restriction enzyme digestion and 2% agarose gel electrophoresis. There was no significant difference in the distribution of Taq I RFLP between healthy controls and adult periodontitis group (P > 0.05). Thus, Taq I RFLP in the vitamin D receptor gene may not confer the susceptibility to adult periodontitis in Korean population. However, t allele distributions of this RFLP showed various frequencies among ethnic groups studied. Further studies in other ethnic groups will be required.

주변 소음이 휴대폰의 명료도에 미치는 영향에 관한 연구

장호경,박학균,김예현,강병용 嶺南大學校 基礎科學硏究所 1994 基礎科學硏究 Vol.14 No.-

To study the communication quality of mobile telephone, the articulation test was conducted in the anechoic- chamber in the condition of monaural and binaural which are controlled by frequency and sound pressure level. Also the articulation test was done in the traveling car speed with and without window closed. The experimental results showed that the articulation in the anechoic-chamber was decreased with noise level and the frequency was not affected, and the articulation in the traveling car was 50-60%. It was concluded with the experimental result that noise strongly affect mobile telecommunication quality in the big city.

마이크로스트립 패치 안테나의 다중 분해능 웨이블릿 산란해석법

강병용,주세훈,빈영부,김형훈,김형동 한국전자파학회 1998 한국전자파학회논문지 Vol.9 No.5

다중 분해능 웨이블릿 해석법을 마이크로스트립 패치 안테나의 산란해석에 적용하였다. 다충구조에 대한 스펙 트럼 영역 그린 함수(spectral domain Green's dyad)의 특성올 공간-스펙트럼 영역 표현법을 이용하여 살펴보고, 스펙트럼 영역 웨이블릿을 주어진 문제에 적용하는 것이 유용함을 관찰하였다. 적분방정식에 모멘트법을 이 용하여 행렬방정식을 얻고, 그 풀이에 CG(conjugate gradient)법과 스펙트럼 영역 웨이블릿올 결합하여 효율 적으로 문제를 풀이할 수 있다. 단충구조 위에 놓인 정방형 패치에 대하여 기폰의 모멘트법 결과와 다충 분해능 웨이블릿 해석법올 적용한 결과를 비교하였다. Microstrip patch antennas are analyzed by a multiresolution wavelet method. The spectral Green's dyad of the structure is obtained and its joint spatial-spectral domain representations are presented. Based on the joint spatial-spectral domain representation, we show that the spectral-domain wavelets are useful in the analysis of this problem. We obtain the matrix equations of the integral equations of this Green's dyad by using the method of moment(MoM), and efficiently solve the problem using the spectral domain wavelet transform concepts in conjuction with the conjugate gradient method. The results for a single-layered square patch are compared with those of conventional MoM and CG-FFT.

Linkang Disequilibrium of Dopamine D2 Receptor Gene in the Korean Population

강병용,Sang Duk Oh,Kang Oh Lee 한국독성학회 2004 Toxicological Research Vol.20 No.1

The genetic basis of hypertension is complex, and has been considered to be associated with the dopamine D2 receptor gene (DD2R). Because association studies using the candidate gene approach may provide important clues regarding the pathogenesis of hypertension and establish basis for further study, we performed the association study on the relationship between genetic polymorphisms in the DD2R gene and hypertension in Koreans. Eighty nine patients with hypertension and 86 age-matched subjects with normal blood pressure were enrolled. Genomic DNA was extracted from peripheral blood leukocytes. PCR-RFLP analysis was performed to detect the three polymorphic Taq I sites in the DD2R gene. There were no significant differences in genotype, allele and haplotype distributions of any polymorphisms in the DD2R gene between two groups, respectively (P>0.05), although significant linkage disequilibriums among these polymorphic sites were detected by pair-wise analysis (P<0.05). Therefore, our negative result suggest that the three Taq I RFLPs in the DD2R gene were not significantly associated with hypertension in Koreans.