Global Trends of Reliability-based design (LRFD)

본 연구는 건설교통부 2005 건설기술기반구축 연구과제 LRFD 기초구조물 설계를 위한 저항계수 결정 연구 및 서울대학교 SIR BK21 (안전하고 지속가능한 사회기반건설)사업단의 연구비 지원에 의해 수행되었으며 이에 감사드립니다

GaAs/AlGaAs 다중양자우물 pin 구조의 부저항 특성을 이용한 광전 소자 연구

학위논문(박사) - 한국과학기술원 : 재료공학과, 1999.2, [ xv, 159 p. ]This thesis demonstrates novel optical logic operations with symmetric self electro-optic effect devices (S-SEEDs), and discusses the physics related to the optical logic operations and studies the feasibility of a novel optical information and processing system. Using an impulse photocurrent response function one can theoretically derive the minimum switching energy for various S-SEED structures. This approach provides a way to determine the optimum structure for the implementation of the devices such as a low drive-voltage, high operation power, device electrical parameters (resistance, inductance and capacitance) and simple device geometry. An impedance-matched asymmetric Fabry-Perot SEED with high power performance is investigated in terms of absorption saturation and ohmic heating problem. Although the operation power is one of the key parameters, the signal properties are degraded mainly by thermal and saturation effect. In order to lessen the problem, the most important condition was to reduce the drive-voltage. However, other parameters such as the signal difference, the contrast ratio, and the operation power have to be improved in terms of bit rate and noise characteristics for a practical switching scheme of various device structures. Utilizing multiple shallow quantum wells (MSQWs) instead of conventional MQWs structures improved the performance of the devices and exploited the fast sweep-out time and high absorption saturation power. A pin diode with stacked structure was constructed and the device showed optimized electric field swing and reduced driving voltage. This structure also showed a low switching energy and reduced thermal problem while maintaining signal properties, which were comparable with other conventional devices. An asymmetric Fabry-Perot (AFP) cavity was employed in the stacked pin-structure to obtain large contrast ratio comparable to that of the conventional pin-structure. A new device scheme without external bias voltage was d...한국과학기술원 : 재료공학과

Load-displacement Behavior of Cast-in-situ Concrete Pile by O-cell test

본 연구는 SISTeC의 연구비 지원에 의해 이루어졌습니다

Electrical and optical properties of CdS films prepared by electrodeposition

학위논문(석사) - 한국과학기술원 : 재료공학과, 1991.2, [ [ii], 56 p. ]한국과학기술원 : 재료공학과