• 국제초고층학회논문집
• /
• 제4권3호
• /
• pp.219-226
• /
• 2015

By the end of 2014, the number of completed and under-construction supertall buildings above 250 meters in China reached 90 and 129, respectively. China has become one of the centers of supertall buildings in the world. Supertall buildings in China are getting taller, more slender, and more complex. The structural design of these buildings focuses on the efficiency of lateral resisting systems and the application of energy dissipation. Furthermore, the research, design, and construction of high-performance materials, pile foundations, and mega-members have made a lot of progress. Meanwhile, more and more challenges are presented, such as the improvement of structural system efficiency, the further understanding of failure models, the definition of design criteria, the application of high-performance materials, and construction monitoring. Thus, local structural engineers are playing a more important role in the design of supertall buildings.

• 한국디자인학회:학술대회논문집
• /
• 한국디자인학회 2001년도 Bulletin of The 5th Asian Design Conference International Symposium on Design Science
• /
• pp.28.1-28
• /
• 2001

• 전자공학회논문지
• /
• 제51권8호
• /
• pp.148-155
• /
• 2014

본 연구에서는 Xilinx의 Zynq SoC(system on chip)를 이용하여 초음파신호의 포락선을 검출하기 위한 신호처리 시스템을 설계하였다. 설계 툴로 Vivado IDE(integrated design environment)를 이용하여, 초음파 신호처리를 위한 전체 과정을 계층적 블록의 형태로 설계하였다. 제안된 시스템은 Zynq-7010의 내장 ADC, FIR(finite impulse response) 밴드패스 필터, 절대값 계산모듈, FIR 로우패스 필터 및 Kalman 필터 등으로 구성되며, 최종 단으로서 FIR 로우패스 필터를 사용하는 HW design 방식과 Kalman 필터를 사용하는 HW/SW co-design 방식에 대해 성능과 유효성을 비교하였다. 비교결과, 포락선 검출 성능에 있어서는 두 방식이 서로 유사한 특성을 갖지만, 시스템 개발에 소요되는 시간 측면에서는 HW/SW co-design 방식이 HW design 방식에 비해 훨씬 더 효율적임이 확인되었다.

• International Journal of Control, Automation, and Systems
• /
• 제5권5호
• /
• pp.515-525
• /
• 2007

In this paper, we develop a co-design methodology of stochastic optimal controllers and network parameters that optimizes the overall quality of control (QoC) in networked control systems (NCSs). A new dynamic model for NCSs is provided. The relationship between the system stability and performance and the sampling frequency is investigated, and the analysis of co-design of control and network parameters is presented to determine the working range of the sampling frequency in an NCS. This optimal sampling frequency range is derived based on the system dynamics and the network characteristics such as data rate, time-delay upper bound, data-packet size, and device processing time. With the optimal sampling frequency, stochastic optimal controllers are designed to improve the overall QoC in an NCS. This co-design methodology is a useful rule of thumb to choose the network and control parameters for NCS implementation. The feasibility and effectiveness of this co-design methodology is verified experimentally by our NCS test bed, a ball magnetic-levitation (maglev) system.

• 한국정보디스플레이학회:학술대회논문집
• /
• 한국정보디스플레이학회 2000년도 제1회 학술대회 논문집
• /
• pp.11-12
• /
• 2000

An 18.1" Thin Film Transistor Liquid Crystal Display (TFT LCD) monitor adopting high brightness In Plane Switching (IPS) technology was realized. While conventional IPS structure used a Chromium (Cr) and Molybdenum (Mo) for a drain electrode, Indium Tin Oxide (ITO) was proposed and verified in this paper. Black sticky micropeal spacers were introduced for the reduction of light scattering phenomena, which was observed at dark room with the conventional micropeal spacers. With the proposed method, more than 10 % aperture ratio was increased and the excellent image quality was obtained.

• Bulletin of the Korean Chemical Society
• /
• 제27권2호
• /
• pp.273-276
• /
• 2006

Three dimensional quantitative structure-activity relationship studies for a series of isatin derivatives as a nonpeptidyl caspase-3 enzyme inhibitor were investigated using comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA). The first approach of non-peptidyl small molecules by 3D QSAR may be useful in guiding further development of potent caspase-3 inhibitors.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2007년도 춘계학술대회B
• /
• pp.2085-2090
• /
• 2007

This paper describes the possible way to improve the capacity, the efficiency and the pressure drop of $CO_2$ system. It is considered the use of an internal heat exchanger (IHX) to improve the performance of the $CO_2$ system. Experiment was performed by changing a tube shape, a tube number and a tube length of IHX to investigate the performance of IHX for $CO_2$ system. The focus of the present study is to obtain the concept on IHX optimal design. Experimental results show that design parameters are closely related with the capacity and the pressure drop of $CO_2$ system. In the transcritical $CO_2$ cycle, the system performance is very sensitive to the IHX design. System performance on operation condition and shape of IHX is also introduced.

• 한국CDE학회논문집
• /
• 제5권3호
• /
• pp.263-275
• /
• 2000

Multidisciplinary design optimization(MDO) can yield optimal design considering all the disciplinary requirements concurrently. A method to implement the collaborative optimization(CO) approach, one of the MDO methodologies, is developed using a pre-compiler “EzpreCompiler”, a design optimization library “EzOptimizer”, and a common object request broker architecture(CORBA) in distributed computing environment. The CO approach is applied to a mathematical example to show its applicability and equivalence to standard optimization(SO) formulation. In a realistic engineering problem such as optimal design of a two-member hub frame, optimal design of a speed reducer and initial design of a bulk carrier, the CO yields better results than the SO. Furthermore, the CO allows the distributed processing using the CORBA, which leads to reduction of overall computation time.

• 한국표면공학회:학술대회논문집
• /
• 한국표면공학회 2002년도 춘계학술발표회 초록집
• /
• pp.39-39
• /
• 2002

In order to improve wear and fatigue resistance of the structural materials, especially cold work roller for 304 stainless steel, an eco-super-finishing and surface hardening treatment using ultrasonic vibration energy was developed and applied to the SKD-ll roller. The eco-super-finishing machine was designed and fabricated by DesignMecha Co, by its own technology. It was observed that the surface roughness, hardness and residual stress were changed from $Ra{\;}={\;}O.25\mu\textrm{m}$, Hv=710 and ${\sigma}$={\;}+400{\;}MPa{\;}to{\;}Ra{\;}={\;}0.165\mu\textrm{m}$, Hv = 1200 and ${\sigma}=-610$ MPa after 20 KHz micro-cold forging, which means almost equal to the 300 % improvement of life-time.

• 한국원자력학회:학술대회논문집
• /
• 한국원자력학회 2005년도 춘계학술발표회
• /
• pp.857-858
• /
• 2005