http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
연료의 옥탄가 변화에 따른 스파크 점화기관의 노킹특성의 변화
이홍철(H.C.Lee),전광민(K.M.Chun) 한국자동차공학회 1992 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-
Knock phenomenon is an abnormal combustion originated from autoignition of unburned gas in the end-gas region during the later stage of combustion process and it accompanys a high pitched metallic noise. Engine Knock is accompanied with a vibration of engine cylinder and when it is severe. it can cause major engine demage. Engine Knock is characterized in terms of knock crank angle. knock pressure, pressure jump and knock intensity.<br/> In this study,a 4-cylinder spark ignition engine was used for experiment and eighty consecutive cycles were analyzed statistically. The purpose of this study is to characterize spark ignition engine knock as a function of ingition timing and fuel research octane number.The result of this study can be summerized as follows. Knockoccurrence angle gradually approached TDC as ignition timing is advanced. Pressure and knock intensity gradually increased as spark timing is advanced. Mean knock occurence angle gradually approached TDC as fuel research octane number is decreased for identical spark timing. Knock intensity increased linearly as RON is decreased.<br/>
국내 시판 육제품의 이화학적, 조직적 특성 및 미생물의 성상
진구복,김경훈,이홍철,Chin Koo-B.,Kim Kyung-H.,Lee Hong-C. 한국축산식품학회 2006 한국축산식품학회지 Vol.26 No.1
본 연구는 시중에 유통되고 있는 육가공품들을 구입하여 이화학적 및 조직적 특성 및 미생물 검사를 통해서 소비자들의 기호성과 적합한 육가공품을 개발하기 위한 기초 자료를 제시하고자 실시하였다. 측정한 19가지 육제품은 소시지와 햄으로 pH는 $5.46{\sim}6.69$, 수분은 $47.6{\sim}65.3%$, 지방은 $14.2{\sim}34.7%$, 그리고 단백질은 $9{\sim}20%$에 이르기까지 다양하였고 햄의 단백질 함량이 소시지에 비하여 높았다. 진공감량은 $2.40{\sim}7.44%$ 범위로 나타났고 원심분리에 의한 유리수분의 함량은 $6.10{\sim}28.3%$의 범위로 독일형 소시지의 보수력이 비교적 낮았다. 육색은 명도가 $59.6{\sim}75.7$, 적색도는 $11.6{\sim}21.1$, 그리고 황색도는 $2.30{\sim}11.4$로 나타났으며 조직감은 각 제품 별로 다양한 수치를 보여 부서짐성, 경도, 탄력성은 계육으로 제조한 Frank A가 가장 높은 반면 응집성, 검성, 저작성은 로인햄과 Beershinken이 비교적 높아 단백질 함량과 상관관계를 보였다. 미생물 검사 결과 총균수는 대부분에서 3.00 log CFU/g 이하이었고 대장균군은 검출되지 않았다(< 2.00 log CFU/g). 이러한 결과로 볼 때 시중에서 판매되는 육제품은 매우 다양하고 비교적 위생적이지만 현대 소비자들의 용구를 충족시키기 위한 기능성 저지방, 저염 기능성 웰빙 육제품의 개발이 필요로 된다. This study was performed to investigate the product characteristics of meat products sold in Korean markets and determine if these products meet the comsumer demands. The total nineteen meat produce were evaluated the physico-chemical, textural properties, and microbial counts of total bacteria and Enterobacteriaceae. pH values were ranged from 5.46 to 6.69, moisture $47.6{\sim}65.3%,\;fat\;14.2{\sim}34.7%,\;and\;9{\sim}20%$ and the pH values of ham products were higher than those of sausages. Purge loss(%) and expressible moisture(%) were ranged $2.40{\sim}7.44\;and\;6.10{\sim}21.2%$ respectively. Varied hunter color values (Lightness $59.6{\sim}75.7$, Redness $11.6{\sim}21.1$, Yellowness $2.30{\sim}l1.4$) were observed. Texture profile analysis values were observed and Frank A sausages made with chicken had highest fracturability, hardness and springiness, whereas loin ham and beershinken had highest cohesiveness, gumminess and chewiness. Most meat products had the total microbial counts of less than 3 log CFU/g and Enterbacteriaceae were not detected (< 2 log CFU/g) in this study. These data suggested that the meat products sold in Korean market were various and relatively safe. In addition, well-being meat products, such as low-fat, salt and containing functional ingredient, should be developed to meet the consumer needs these days.
NHPP 기반의 신뢰성 성장 예측 모델에 대한 민감도 분석
조강훈(K. H. Cho),이홍철(H. C. Lee),장중순(J. S. Jang),박상철(S. C. Park) 한국신뢰성학회 2016 신뢰성응용연구 Vol.16 No.4
Purpose: The purpose of this study is to provide a sensitivity analysis of system reliability for recognizing effectiveness of changing of BD mode failures using reliability growth projection model based on NHPP. Methods: Crow extended reliability projection model (CERPM) is used to analyze the changing of two factors 1) the number of BD mode failures, 2) fix effectiveness factor (FEF) values. Results: The system reliability has increased in accordance with the number of BD mode failures and FEF values have increased. Conclusion: It is necessary to design failure modes and FEF values to supervise the reliability
원샷 시스템의 저장 신뢰성 추정 정확성에 대한 샘플링 시점의 영향 분석
정용호(Yong H. Chung),오봉식(Bong S. Oh),이홍철(Hong C. Lee),박희남(Hee N. Park),장중순(Joong S. Jang),박상철(Sang C. Park) 한국신뢰성학회 2016 신뢰성응용연구 Vol.16 No.1
Purpose: The purpose of this study is to analyze the effect of sampling points on accuracy of storage reliability estimation for one-shot systems by assuming a weibull distribution as a storage reliability distribution. Also propose method for determining of sampling points for increase the accuracy of reliability estimation. Methods: Weibull distribution was divided into three sections for confirming the possible to estimate the parameters of the weibull distribution only some section’s sample. Generate quantal response data for failure data. And performed parameter estimation with quantal response data. Results: If reduce sample point interval of 1 section, increase the accuracy of reliability estimation although sampling only section 1. Even reduce total number of sampling point, reducing sampling time interval of the 1 zone improve the accuracy of reliability estimation. Conclusion: Method to increase the accuracy of reliability estimation is increasing number of sampling and the sampling points. But apply this method to One-shot system is difficult because test cost of one-shot system is expensive. So propose method of accuracy of storage reliability estimation of one-shot system by adjustment of the sampling point. And by dividing the section it could reduce the total sampling point.
조강훈(K. H. Cho),이홍철(H. C. Lee),장중순(J. S. Jang),박상철(S. C. Park) 한국신뢰성학회 2016 신뢰성응용연구 Vol.16 No.3
Purpose: The purpose of this study is to provide a comparison of reliability prediction models between MIL-HDBK-217F and Telcordia SR-332 and to analyze the reliability prediction results. Methods: The reliability of industrial tablet PC was predicted using MIL-HDBK-217F and Telcordia SR-332. To analyze the results, sensitivity analysis was conducted. Results: The reliability of MIL-HDBK-217F was predicted lower than the one of Telcordia SR-332. Considering the factors such as temperature, quality and environment, those provided reliability change of a particular part which highly contribute to the system failure. Conclusion: It is necessary to design the industrial tablet PC that consists of integrated circuits such as microprocessor and memory considering the operating temperature and quality factors.