• International Journal of Automotive Technology
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• 제8권2호
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• pp.233-241
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• 2007

A lumped parameter model is proposed for the analysis of dynamic behaviour of a Passive Hydraulic Engine Mount (PHEM), incorporating inertia track and throttle, which is characterized by effective and efficient vibration isolation behaviour in the range of both low and high frequencies. Most of the model parameters, including volume compliance of the throttle chamber, effective piston area, fluid inertia and resistance of inertia track and throttle are identified by an experimental approach. Numerical predictions are obtained through a finite element method for responses of dynamic stiffness of the rubber spring. The experiments are made for the purpose of PHEM validation. Comparison of numerical results with experimental observations has shown that the present PHEM achieves good performance for vibration isolation.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2006년도 춘계학술대회 논문집
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• pp.249-253
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• 2006

Because of the high cost for the active power filter, passive filters have been widly used to absorb harmonic currents of nonlinear loads and can also improve the power factor. They are not often optimal filters because the passive filters are designed with the fixed load conditions. In this paper we proposed the method which only the necessary harmonic filters are operated by detecting the various harmonic current components. By the experimental results using the proposed system for the 500VA rectifier load, we concluded that the researched hybrid filter is cost effective and the performance is better than the passive filter.

• 한국전기전자재료학회논문지
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• 제15권4호
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• pp.344-348
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• 2002

As microelectronics technology continues to progress, there is also a continuous demand on highly integration and miniaturization of systems. For example, it is desirable to package several integrated circuits together in multilayer structure, such as multichip modules, to achieve higher levels of compactness and higher performance. Passive components (i.e., capacitors, resistors, and inductors) are very important fort many MCM applications. In addition, the low-temperature co-fired ceramic (LTCC) process has considerable potential for embedding passive components in a small area at a low cost. In this paper, we investigate a method of statistically modeling integrated passive devices from just a small number of test structures. A set of LTCC inductors is fabricated and their scattering parameters (s-parameters) are measured for a range of frequencies from 50MHz to 5GHz. An accurate model for each test structure is obtained by using a building block based modeling methodology and circuit parameter optimization using the HSPICE circuit simulator.

• 한국소음진동공학회논문집
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• 제12권12호
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• pp.964-969
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• 2002

The flexural vibration of laminated composite beams with passive constrained layer damping has been investigated to design structure with maximum possible damping capacity. The equations of motion are derived for flexural vibrations of symmetrical, multi-layer laminated beams. The damping ratio and modal damping of the first bending mode are calculated by means of Iterative complex eigensolution method. This paper addresses a design strategy of laminated composite under flexural vibrations.

• 대한치과보철학회:학술대회논문집
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• 대한치과보철학회 2000년도 추계학술대회
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• pp.27-28
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• 2000

• 한국항공우주학회지
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• 제42권5호
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• pp.423-429
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• 2014

히스테리시스 댐퍼를 조합한 영구자석과 중력붐을 적용한 수동형 자세제어 안정화 방식은 시스템의 단순화가 가능하여 임무목적에 따라 큐브위성의 자세제어에 용이하게 적용되고 있다. 상기의 자세제어 안정화 방식을 적용한 경우, 큐브위성의 자세 프로파일은 상이하며, 본 논문에서는 각각의 자세제어 방식 적용에 따른 큐브위성의 열적 특성을 궤도 열해석을 통해 분석하였다. 또한, 통신용 안테나 장착 등의 목적으로 태양전지셀이 장착되지 않는 판넬 표면의 상이한 열코팅 적용에 따른 큐브위성의 열적 영향을 분석하였다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.871-875
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• 2003

To detect and avoid obstacles is one of the important tasks of mobile navigation. In a real environment, when a mobile robot encounters dynamic obstacles, it is required to simultaneously detect and avoid obstacles for its body safely. In previous vision system, mobile robot has used it as either a passive sensor or an active sensor. This paper proposes a new obstacle detection algorithm that uses a stereo camera as both a passive sensor and an active sensor. Our system estimates the distances from obstacles by both passive-correspondence and active-correspondence using laser slit. The system operates in three steps. First, a far-off obstacle is detected by the disparity from stereo correspondence. Next, a close obstacle is acquired from laser slit beam projected in the same stereo image. Finally, we implement obstacle avoidance algorithm, adopting the modified Dynamic Window Approach (DWA), by using the acquired the obstacle's distance.

• 한국주거학회논문집
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• 제13권2호
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• pp.73-78
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• 2002

Recently, the energy consumption has been sharply increased and the environmental pollution has been serious, resulted in increased use of fossil fuel. These facts are applied to most fields, and are especially important issues in the field of architecture. The energy consumption rate of building is about 30% of all energy consumption, and the rate of residential is about 20% of the rate of building and is increasing gradually. The purpose of this article is firstly to analyse an actual energy consumption rate of model building and compare it with alternative methods, which are applied passive system to, and secondly to suggest an optimal passive method for saving energy. The conclusion of this study is as follows; 1) As compared with the existing house on actual energy consumption rate, 6% in changing orientation to a south, 9% in using double low-e glazing and 23% in shading is decreased. 2) The change of insulation from 50 to 100mm did not show dramatical difference in energy consumption rate. 3) As changed indoor temperature at 2$0^{\circ}C$ in winter and 27$^{\circ}C$ in summer, the rate shows a reduction of 14% compared with the existing condition.

• 한국항공우주학회지
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• 제33권6호
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• pp.8-14
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• 2005

지면 근처에 존재하는 뭉뚝한 물체의 유동장 이해는 자동차 및 항공 업계에 매우 중요한 분야이다. 이를 위해 비압축성 평균 Navier-Stokes 방정식에 $\varepsilon{-SST}$ 난류 모델을 적용하여 정사각주와 이동 지면의 간극 유동을 해석하였다. 비정상 진동을 억제하기 위하여 사각주 하부에 수직/수평의 펜스 설치 효과를 연구하였다. 지면이 운동할 경우에는 지면의 박리 전단층의 강도가 약화되어 사각주 상/하부의 박리 전단층 상호 작용을 촉진시키므로 고정 지면에 비하여 더 낮은 간극에서도 와류 배출이 발생한다.

• 대한한의학방제학회지
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• 제15권2호
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• pp.147-160
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• 2007

Objectives: This study is carried out to investigate the anti-stress effects of the sihoueokgantang in rats. Methods: we performed the passive avoidance test and the forced swimming test. The degrees of TH were also measured with immunohistochemical method in the regions of VTA and LC. Results: 1. As the results of the passive avoidance test. the sihoueokgantang showed tendency to improvement in compared with control group. 2. As the results of the forced swimming test, immobility of rats was significantly decreased in sihoueokgantang in compared with control group. 3. As the results of TH expression in the region of the LC, TH-immunoreactive cells were significantly decreased in the sihoueokgantang 100 mg/kg. As the results of TH expression in the region of the VTA. TH-immunoreactive cells were significantly decreased in the sihoueokgantang 400 mg/kg. Conclusion: As the results above, it can be considered that sihoueokgantang has the effects of preventing depression and memory decrease caused by stress.