스크램제트 연소기내에서의 연료제트 분사 및 혼합에 관한 수치모사

학위논문(석사)--서울대학교 대학원 :항공우주공학과,1996.Maste

A Study on the Mechanical Properties of EMC and Thermal Stress Analysis in Electronic Packaging

In this study, as a part of basic study for developing the simulation program for the assemssment of reliability of electronic EMC packaging which covers from EMC mixing step to thermal analysis, comparison between a measured and predicted values of material properties of EMC and finitde element analysis of thermal stress are performed. For the experimental testing specimens of fifty, sixty hive and eighty percent filler($13\mu m$, spherical silica) weight fraction are fabricated using tranfer molding. Coefficient of thermal expansion, elastic modulus and thermla conductivity are measured using these specimens and then these measured values are compared with the predicted values by various equations ( such as dilute suspension method. self consistent method, generalized self consistent method, Hashin-Shtrikmans bounds. Shaperys bounds, Nielsens method and others). Measured values are distributed within the upper and lower bounds of equations. Measured elastic modulus and coefficient of thermal expansion approaches closely the perdicted values with self consisten mehtod and upper bound of Shaperys equation respectively. However small differences of thermal conductivity between the different filler volume fraction are obserbed. FEM analysis indicates that firstly stress is concentrated at the corner section of EMC and secondly EMC with eighty percent filler weight fraction shows less thermal stress when package is cooling down and relatively high thermal stress when package is heating up

Tolerance allocation of gears using Monte Carlo Simulation and taguchi method

학위논문(석사) - 한국과학기술원 : 기계공학과, 1994.2, [ iv, 67 p. ]한국과학기술원 : 기계공학과

A study on the dynamic energy release rate and T stress of bimaterial interfacial crack

학위논문(박사) - 한국과학기술원 : 기계공학전공, 2001.2, [ x, 130 p. ]한국과학기술원 : 기계공학전공