• 대한기계학회논문집
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• 제18권11호
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• pp.3075-3083
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• 1994

The applications of the electrical transmission line theory to the pressure propagation characteristics in the volume loaded fluid transmission line with step and impulse input wave is demonstrated in this paper. The method is based on the premise that the time response is the inverse Fourier transform of frequency spectrum of the wave which spectrum is a product of frequency spectrum of input pressure wave and system transfer function. The frequency response and transient response of step and impulse input wave in the volume loaded fluid transmission line is analysed by the Laplace transform and inverse Laplace transform with FFT numerical algorithm. The numerical solution of the distributed friction model is compared with the average friction model and the infinite product model. And the result is showed that FFT method may have major advantages for the simulation of fluid circuitary.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 하계종합학술대회 논문집(5)
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• pp.99-102
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• 2000

This study analyze of reflection wave to Acoustic stimulation on acupoints and contrast parts for objectification of the meridian substance. In order to verify meridian pathway and channel theory of bio-energy in body. It was analyzed response characteristic of reflection waves after acoustic stimulation by sound wave of 5 specific tones. The response characteristics of reflection are measured by the average current magnitude of meridian. The current variation ratio are Live Meridian(gung) 33.2%, Heart Meridian(sang) 30.7%, Kidney Meridian (gak) 33.1%, Spleen Meridian(chi) 33.9%, Lung Meridian (wo) 30.7% compare with contrast parts (non-acupoint and meridian). Therefore meridian is distinguished to non-meridian and 5 vital meridians have relationship with sound wave of 5 specific tones.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2012년도 추계학술대회 논문집
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• pp.110-114
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• 2012

We studied on the nondestructive evaluation of the elastic wave signal of SiC ceramics and SiC/SiC composite ceramics under monotonic tensile loading. The elastic wave signal of cross and unidirectional SiC/SiC composite ceramics were obtained by pencil lead method and bending test. It was applied for the time-frequency method which used by the discrete wavelet analysis algorithm. The time-frequency analysis provides time variation of each frequency component involved in a waveform, which makes it possible to evaluate the contribution of SiC fiber frequency. The results were compared with the characteristic of frequency group from SiC slurry and fiber. Based on the results, if it is possible to shift up and design as a higher frequency group, we will can make the superior material better than those of exiting SiC/SiC composites.

• 제어로봇시스템학회논문지
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• 제17권3호
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• pp.258-263
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• 2011

In the bilateral tele-operation system, time delay may be a critical problem. Even if system modeling error or time delay occurs, when applied to wave transformation system, the system's stability can be achieved. Using the characteristic b which is an important parameter of wave transformation, the system can display robust performance for time delay. However, since assuming and that the time delay was fixed developing a theory, a stability cannot be guaranteed about the time-varying delay. Therefore, In the paper, Therefore, in this paper, we studied for the method that controls this by applying the fuzzy algorithm which surveyed the timevarying delay characteristics and can adjust the b according to it adaptively.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제55권5호
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• pp.272-277
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• 2006

The present study is devoted to investigate numerically the optical characteristics of multi-layer thin film structures such as $Si/SiO_2\;and\;Ge/Si/SiO_2$ by using the characteristics transmission matrix method. The reflectivity and the absorptivity rate for thin film structures are estimated for different incident angles of rays and various film thicknesses. In addition, the influence of wavelength on optical characteristics related to complex refractive index is examined. It is found that such wave-like characteristics are observed in predicting reflectivities and depends mainly on film thickness. Moreover, the present study predicts the film thickness for ignoring wave interference effects, and it also discusses the fundamental physics behind optical and energy absorption characteristics appearing in multi-layer thin film structures.

• 제어로봇시스템학회논문지
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• 제9권8호
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• pp.600-609
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• 2003

A hybrid stabilization approach involving both Passivity Observer/passivity Controller and wave variables is addressed to stabilize the teleoperation system with time delay. To guarantee the stability of master or slave side, Passivity Observer and Passivity Controller are applied. But Passivity Observer and Passivity Controller technique cannot deal with communication delay and even small communication delay cause the system to be unstable. To cope with this problem, wave variables are additionally employed to have robustness to arbitrary delays. To show the validity of our proposed approach, several computer simulation results are illustrated.

• 한국음향학회지
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• 제20권1호
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• pp.30-35
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• 2001

에밀레 소리 울림의 최대 특징은 맥놀이 파동의 생성이다. 이는 시간영역에서는 간섭 곱셈의 결과로 나타나며 반소파는 억제하면서 신호파가 좌우에 분포하는 대역 억압 양측파대 변조방식이다. 이러한 맥놀이파는 에밀레의 파동 이외도 폴리비닐에 대한 라만 분산신호, 음성신호, 수맥파와 조석파 등에서 관찰된다. 이러한 맥놀이의 발생원인은 대칭구조에서 비대칭 구조로 발생함을 보여주고 있다.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2001년도 춘계 학술대회논문집
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• pp.116-120
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• 2001

The impactive Pressure wave induced by pyro valve in the pressurization system of KSR-III may result in fatal failure or malfunction of valves, so it is important to know the pressure wave characteristic in the pressurization system. An unsteady flow analysis in the simplified pressurization system was peformed by Finite difference method.

• 전기학회논문지P
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• 제58권4호
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• pp.465-468
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• 2009

The dispersion relation and the characteristic of propagation are measured. The measurements of the dispersion relation are observed by a plunger method employed in slow plasma density by pumping microwaves on the axis are observed in plasma loaded slow wave structure. In case of small incident microwave powers the well known plasma density cavity are observed. At the axial positions of minimal radius in the waveguides, the maxima og the electron density, the plasma potential and the RF electric field are observed in cases of high-power microwaves.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 하계종합학술대회 논문집
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• pp.1149-1152
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• 1999

A gain controllable precision full-wave rectifier for the measurements of small-signal voltage is presented. It consists of gain controllable inverter superdiode and noninverter superdiode. The results of simulation with PSpice and experiment on breadboard show that the proposed rectifier has the characteristic of precise rectification and amplification for small signal voltage.