http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
방수재료의 거동대응성능 시험시 비 구속조건에서의 구조물 거동 대응성능 평가의 한계와 향후 개선 방안 제안
안기원 ( An¸ Ki-won ),오규환 ( Oh¸ Gyu-hwan ),김수연 ( Kim¸ Soo-yeon ),오상근 ( Oh¸ Sang-keun ) 한국건축시공학회 2021 한국건축시공학회 학술발표대회 논문집 Vol.21 No.2
As structure and the waterproofing material are compressed through the backfilling process after the waterproofing material is installed on the underground structure at the actual site, there is a difference between the behavioral response force of the waterproofing material in the compressed state and the behavioral response force in the non-constrained state. In this regard, we will analyze the limitations of the current structural behavioral response evaluation and suggest an improvement plan so that the future test and evaluation environment can be evaluated under conditions similar to the field.
강체전차선로 고속화를 위한 설계파라미터 민감도 분석 연구
이기원(Kiwon Lee),조용현(Kiwon Lee),권삼영(Sam-Young Kwon),박영(Young Park) 대한전기학회 2017 전기학회논문지 Vol.66 No.2
R-Bar (Overhead Rigid Conductor system) has been lately used for the speed of over 200 ㎞/h in Europe, while it has been developed and used for the max. speed of 120 ㎞/h in Korea. Because R-Bar has advantages of reduction of tunnel cross sectional area and maintenance, its development for more high-speed is urgent in Korea having many mountain area. Therefore a sensitivity analysis of design parameters for the speed-up of R-Bar has performed in this study. For the analysis, we have developed a program for the prediction of dynamic characteristics between a pantograph and R-Bar. The program was evaluated with the actual test result and a current collection performance according to the parameters such as a distance between brackets, a stiffness of bracket and of R-Bar rail was predicted with the program.
Ultrasonic Bonding Using Anisotropic Conductive Films (ACFs) for Flip Chip Interconnection
Kiwon Lee,Hyoung-Joon Kim,Myung-Jin Yim,Kyung-Wook Paik IEEE 2009 IEEE transactions on electronics packaging manufac Vol.32 No.4
<P>In this paper, a novel anisotropic conductive film (ACF) flip chip bonding method using ultrasonic vibration for flip chip interconnection is demonstrated. The curing and bonding behaviors of ACFs by ultrasonic vibration were investigated using a 40-kHz ultrasonic bonder with longitudinal vibration. In situ temperature of the ACF layer during ultrasonic (U/S) bonding was measured to investigate the effects of substrate materials and substrate temperature. Curing of the ACFs by ultrasonic vibration was investigated by dynamic scanning calorimetry (DSC) analysis in comparison with isothermal curing. Die adhesion strength of U/S-bonded specimens was compared with that of thermo-compression (T/C) bonded specimens. The temperature of the ACF layer during U/S bonding was significantly affected by the type of substrate materials rather than by the substrate heating temperature. With room the temperature U/S bonding process, the temperature of the ACF layer increased up to 300degC within 2 s on FR-4 substrates and 250degC within 4 s on glass substrates. ACFs were fully cured within 3 s by ultrasonic vibration, because the ACF temperature exceeded 300degC within 3 s. Die adhesion strengths of U/S-bonded specimens were as high as those of T/C bonded specimens both on FR-4 and glass substrates. In summary, U/S bonding of ACF significantly reduces the ACF bonding times to several seconds, and also makes bonding possible at room temperature compared with T/C bonding which requires tens of seconds for bonding time and a bonding temperature of more than 180degC.</P>
Electronic structures and relevant physical properties of Ni2MnGa alloy films
Kiwon Kim,Jinbae Kim,Jooyull Rhee,Meidong Huang,Nina Lee,이영백,Yurie Kudryavtsev 한국물리학회 2004 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.45 No.1
The electronic structures and physical properties of the ordered and disordered Ni2MnGa alloy lms were investigated in this study. Ordered and disordered Ni2MnGa alloy lms were prepared by ash evaporation onto substrates maintained at 720 K and 150 K, respectively. The results show that the ordered lms behave in nearly the same way as the bulk Ni2MnGa ferromagnetic shape-memory alloy, including the martensitic transformation at 200 K. It was also revealed that the lm deposition onto substrates cooled by liquid nitrogen leads to the formation of a substantially-disordered or an amorphous phase which is not ferromagnetically ordered at room temperature. An annealing of such an amorphous lm restores its crystallinity and also recovers the ferromagnetic order. It was also claried how the structural disordering in the lms in uences the physical properties, including the loss of ferromagnetism in the disordered lms, by performing electronic-structure calculations and a photoemission study.