• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2005년도 학술발표회 논문집
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• pp.177-184
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• 2005

Even in moderate to low seismic regions like Korean peninsular where wind loading usually governs the structural design of a tall building, the probable structural impact of the design basis earthquake or the maximum credible earthquake on the selected structural system should be considered at least in finalizing the design. In this study, by using response spectrum analysis and time history analysis method, seismic performance evaluation was conducted for wind-designed concentrically braced steel highrise buildings. Input ensemble was normalized to be compatible with expected peak ground acceleration. The analysis results showed that wind-designed concentrically braced steel highrise buildings possess significantly increased elastic seismic capacity due to the system overstrength resulting from the wind-serviceability criterion and the width-to-thickness ratio limits on steel members. The time history analysis tended to significantly underestimated the seismic response as compared to response spectrum analysis. Further detailed studies regarding selection and scaling scheme of input ground motions is needed.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2012년도 춘계학술발표대회 논문집
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• pp.494-497
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• 2012

A methodology to predict the output performance of small hydro power using treated effluent in wastewater treatment plant has been studied. Existing plant located Kyunggi-Do were selected and the output performance characteristics for these plants were analyzed. As a result, it was found that the developed model in this study can be used to analyze the output characteristics for small hydro power in wastewater treatment plant. Additionally, primary design specifications such as design flowrate, capacity, operational rate and annual electricity production were estimated and discussed.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2012년도 춘계학술발표대회 논문집
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• pp.498-501
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• 2012

A methodology to evaluate the performance analysis for micro hydropower sites has been studied. It consists of two main parts; flow duration function which can describe micro hydropower sites and performance analysis to estimate the output characteristics of micro hydropower plants. The output performance characteristics for Magok stream was analyzed, using developed model. Also, primary design specifications such as design flowrate, installed capacity, operational rate and annual electricity production were estimated and dicussed. Additionally, it was found that the developed model in this study is useful tool to estimate feasibility assessment for micro hydropower sites.

• 전자공학회논문지S
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• 제35S권5호
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• pp.75-82
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• 1998

Conventional vector quantization (VQ) codebook design methods have several drawbacks such as edge degradation and high computational complexity. In this paper, we first made activity coordinates from the horizonatal and the vertical activity of the input block. Then it is mapped on the 2-dimensional interconnected codebook, and the codebook is designed using kohonen self-organizing map (KSFM) learning algorithm after the search of a codevector that has the minumum distance from the input vector in a small window, centered by the mapped point. As the serch area is restricted within the window, the computational amount is reduced compared with usual VQ. From the resutls of computer simulation, proposed method shows a better perfomance, in the view point of edge reconstruction and PSNR, than previous codebook training methods. And we also obtained a higher PSNR than that of classified vector quantization (CVQ).

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2010년도 춘계 학술대회 제22권1호
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• pp.405-406
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• 2010

본 연구에서는 Bayesian 확률법을 이용한 성능기반형 배합설계방법(Perfomance Based Mixture Design, 이하 PBMD)을 고강도 콘크리트 배합설계에 활용하여 요구성능을 만족하는 고강도 콘크리트 배합비를 찾는 것을 목표로 하고 있다. 고강도 콘크리트의 여러 가지 재료 성능 변수들을 구하기 위해 수행한 여러 가지 실험들의 결과를 바탕으로 고강도 콘크리트 배합설계 시 PBMD 방법의 적용가능성에 대해 검토하였으며 지역에 따른 환경조건, 사용 가능한 재료, 적용 가능한 콘크리트생산기술 등을 고려하여 목표성능을 만족시키는 최적의 콘크리트 배합비를 구하는 과정을 PBMD 방법을 적용한 예제를 통해 나타내었다.

• 방재기술
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• 통권28호
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• pp.48-54
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• 2000

The technique detects radiant energy form a flaming fire of fuels contained carbonaceous material can be applied to fast growing fires. This technique applied detectors are ultimately effective when early detecting fire alarm system is required or the smoke and heat detectors can not applied. In Korea Fire regulation, a flame detector should be install in case that the installation height is higher than 20[m], chemical plant, hangar refinery. Therefore it is really necessary that a flame detector has to be developed as soon as possible. With foundation technique of flame detector, ideal sensing element and stable circuit design, a trial UV flame detector is manufactured. The stable and reliable technique of flame detector is established through the repeateed perfomance test and modification. An early detecting fire alarm device is developed through the modification, supplement of the structure and circuit. Results of the R & D for the manufacture of an excellent flame detecting device is carried out with the establishment of technique for the mass production and the qualified manufacturing process.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 추계학술대회논문집
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• pp.439-443
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• 2006

In this paper, a design of milli-gripper using piezoelectric actuator and flexible hinge structure has been suggested, and the dynamic characteristics of the milli-gripper has been analysed and improved. The milli-gripper consists of the operating and amplifier parts, and the perfomance of the gripper be heavily influenced by base excitation disturbances. The dynamic characteristics of milli-gripper has been measured by the FRF based on experimental modal analysis. It has been found by a series of experiments that the performance of the milli gripper using PID control is made a remarkable improvement in terms of gripping forces.

• 전자공학회논문지D
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• 제35D권1호
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• pp.34-40
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• 1998

For applicating to 10-Gbit/s optical transimission systems, we have designed and fabricated a laser driver IC with extremely-high-operation-frequencies using AlGaAs/GaAs heterojunction bipolar transistors (HBTs), and have investigated its performances. Circuits design andsimulation were performed using SPICE and LIBRA. A discrete AlGaAs/GaAs HBT with the emitter area of 1.5*10 .mu.m$^{2}$, used for the circuit fabrication, exhibited cutoff frequency of 63 GHz andmaximum osciallation frquency of 50 GHZ. After fabrication of MMICs, we observed the very wide bandwidth of DC~18 GHz and the S$_{21}$ gain of 17 dB for a laser driver IC from the on-wafer measurement. Metal-packaged laser driver IC showed the excellent eye opening, the modulation currents of 32 mA, the rise/fall time of 40 ps, measured at the data rates of 10-Gbit/s.

• 한국자동차공학회논문집
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• 제4권2호
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• pp.158-165
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• 1996

The knowledge of air flow in an engine room has become more and more important in recent car design. The fluid flow in the engine compartment was investigated by numerical analysis. Due to the complex geometry of the engine compartment, mesh generation is a time-consuming job. In this research, the "ICEM" code was used to generate meshes by the Cartesian mesh model. The Reynolds-averaged Navier Stokes equations, together with the porous flow model for radiator and condenser, were solved. Computation was performed for the steady, incompressible, and high speed viscous flow, adopting the standard K-ε turbulence model. The "STAR-CD" code was used as a solver. The effect of car front openning area on the flow in engine room was also investigated.

• 조명전기설비학회논문지
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• 제24권1호
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• pp.145-151
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• 2010

영구자석의 반발력을 이용한 반송장치에서 캐리어를 받아 다음 스테이션으로 방향을 전환해주기 위한 회전판의 제어를 수행하기 위한 제어기로서 적당한 모터의 선정을 위하여 두 가지 형태의 제어기를 만들고 이를 비교하여 최적의 제어기를 선정하고자 하였다. 즉 스텝모터를 사용한 마이크로스텝방식의 오픈루프 제어와 DC모터를 사용한 폐루프 제어방식의 DC서보 방향제어기를 설계하고 제작하였다. 이 두 방식의 방향제어기의 성능과 제어특성을 비교하였다.