http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
미니밀 공정의 회귀식 모델링에 의한 제품품질향상에 관한 연구
이명학,하성도,Lee, Myung-Hak,Ha, Sung-Do 대한산업공학회 1999 산업공학 Vol.12 No.1
Mini-Mill process has been recently in operation at Pohang steel company, which enables more flexible steel coil production on customer demands. The effects of process parameters in Mini-Mill process need to be analyzed not only to make the process stable but also to improve product quality. This work aims to develop a regression model of Mini-Mill process using accumulated product data such that the process parameter effects on product tensile strength may be analyzed. The analysis shows that tensile strength is influenced mainly by the amount of components such as carbon, manganese, silicon, and sulfur. The effect of temperature is shown to be small. It is concluded that control of the components is much more responsible for both meeting the target and reducing the variation of the product tensile strength. Heat treatment is more useful in compensating tensile strength variations due to thickness differences and improving workability and other quality characteristics. More work is necessary for establishing regression expressions of the process that is reliable and accurate enough to dispense with the off-line inspection of the product tensile strength.
한형석(Han Hyung-Suk),허신(Hur Shin),하성도(Ha Sung-Do) 한국철도학회 1999 한국철도학회 학술발표대회논문집 Vol.- No.-
A wheel/rail contact module for dynamics analysis of railway vehicles is developed. The developed module is based on non-linear contact and FASTSIM algorithm which calculates contact forces. And the module is incorporated into the general purpose program DADS using user-defined subroutines. The simulation results of this developed program is compared to those of the railway vehicle dynamics analysis program AGEM. Since the module is based on DADS, various simulation environments can be considered.
한형석(Han Hyung-Suk),허신(Hur Shin),하성도(Ha Sung-Do Cho),조동현(Cho Dong-Hyun) 한국철도학회 1998 한국철도학회 학술발표대회논문집 Vol.- No.-
Sensitivity analysis of suspension elements of an articulated bogie for light railway vehicles is presented. The ride, stability and safety are used as dynamic performance index. Suspension elements of 10 and a conicity of wheel are used as design variables. To analyze sensitivity of design variables, the railway vehicle dynamics analysis program AGEM is used. The results shows that the secondary suspension elements have a strong effect on ride and the primary suspension elements have a moderate effect on ride. Conicity of wheel has a strong effect on the stability. The safety is not effected by all the design variables.
허신(Hur Shin),박찬경(Park Chan-Kyung),한형석(Han Hyung-suk),하성도(Ha Sung-Do) 한국철도학회 1999 한국철도학회 학술발표대회논문집 Vol.- No.-
In this paper, running performance analyses of an articulated light rail vehicle are carried out using VAMPIRE software package. The stability analysis to determine the critical speed and the safety analysis such as derailment coefficients, lateral forces of wheels and reduction of wheel load are carried for the track conditions of straight, transition and curving range to the operating velocity of 40 Km/h. Also, ride quality is analyzed. As the results of analysis, the safety of light rail vehicle satisfied with the limit values and the ride quality for tare and full load condition was shown to the "not uncomfortable" level in ISO 2631-1(1997) criteria.