• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 한국소음진동공학회 2007년도 춘계학술대회논문집
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• pp.1027-1032
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• 2007

For the description of the elastic properties of linear objects a convenient parameter is the ratio of the stress to the strain, a parameter called the Young's modulus of the material. Young's modulus can be used to predict the elongation or compression of an object as long as the stress is less than the yield strength of the material. Conventional method for estimating Young's modulus measured the ratio of stress to corresponding strain below the proportional limit of a material using a tensile testing machine. But the method needs precision specimens and expensive equipment. In this paper, we proposed method for estimating Young's modulus using accelerometer. The basic idea comes from that the wave velocity is different as the Young's modulus. To obtain Young's modulus, a group velocity is obtained. It is difficult to measure group velocity. This is because plate medium has a dispersive characteristics which has different wave speed as frequency. In this paper, we used Wigner-Ville distribution to measure group velocity. To verify the proposed method, steel and acryl plate experiments have been performed. Experimental results show that the proposed method is powerful for estimating Young's modulus.

• Journal of Korean Medical classics
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• 제29권1호
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• pp.1-15
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• 2016

Objectives : The purpose of this study is to investigate the method of setting up logic and estimate Fang Youzhi's work through Shanghanluntiaobian. Methods : Wang Shuhe's old edition Shanghanlun and Fang Youzhi's Shanghanluntiaobian were compared and several essential provisions were analyzed and addressed the positive and negative aspects of Fang Youzhi's revising old edition Shanghanlun mixed bamboo tablets. Results : Fang Youzhi's changing Bianmaifa("辨脈法") and Pingmaifa("平脈法") and placement Bianchishiyemaizhengbingzhi chapter after Liujingbingmaizhengbingzhi for discriminating convulsion dampness summer heat stroke from febrile diseases is appropriate. Fang Youzhi's deletion Shanghanli("傷寒例") chapter that has a guiding characteristics shows his editorial policy. Fang Youzhi's addition Bianwenbingfengwenzabingmaizhengbingzhi chapter is for discriminating febrile disease from epidemic febrile disease wind warmth syndrome miscellaneous disease and it indicates Shanghanlun is a book of treatment after differentiation of syndromes containing epidemic febrile disease and miscellaneous disease. Through Fang Youzhi's revising method I can see several positive aspects. First he tried to refine the logic of the content of Shanghanlun and accord with an actual situation. Second he shows Shanghanlun is a book of treatment after differentiation of syndromes containing epidemic febrile disease and miscellaneous disease and tried to see Shanghanlun clearly. A criticism of the Preserving Old Edition Shanghanlun group could interrupt flexibility and creative thinking reading Shanghanlun and a criticism to the Sangangdingli Principles of the several exegetists is a productive criticism because medicine treats human being so it cannot be completed by a logic. Conclusions : All of these processes are Fang Youzhi's endeavour for strengthening the system and logicality of the old edition Shanghanlun and it is meaningful to show a method to read Shanghanlun to beginners.

• 대한생식의학회:학술대회논문집
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• 대한불임학회 2001년도 제40차 춘계학술대회
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• pp.80.1-80.1
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• 2001

• Journal of computational fluids engineering
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• 제15권2호
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• pp.35-40
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• 2010

In the present work, LES with new variational multiscale method is conducted on the fully developed channel flow with Reynolds number, 180 based on the friction velocity and the channel half width. Incompressible Navier-Stokes equations are integrated using finite element method with the basis function of NURBS. To solve space-time equations, Newton's method with two stage predictor multicorrector algorithm is employed. The code is parallelized using MPI. The computational domain is a rectangular box of size $2{\pi}{\times}2{\times}4/3{\pi}$ in the streamwise, wall normal and spanwise direction. Mean velocity profiles and velocity fluctuations are compared with the data of DNS. The results agree well with those of DNS and other traditional LES.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2009년 추계학술대회논문집
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• pp.56-59
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• 2009

In the present work, LES with new variational multiscale method is conducted on the fully developed channel flow with Reynolds number is 180 based on the friction velocity and the channel half width. Incompressible Navier-Stokes equations are integrated using finite element method with the basis function of NURBS. To solve space-time equations, Newton's method with two stage predictor multicorretor algorithm is employed. The code is parallelized using MPI. The computational domain is a rectangular box of size $2{\pi}{\times}2{\times}4/3{\pi}$ in the streamwise, wall normal and spanwise direction. Mean velocity profiles and velocity fluctuations are compared with the data of DNS. The results agree well with those of DNS and other traditional LES.

• Journal of the Korea Institute of Military Science and Technology
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• 제10권4호
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• pp.38-51
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• 2007

This paper describes research results for the measurement and analysis method of magnetic signatures generated from the ship's magnetic mock-up model. In this paper, we present the theoretical and experimental techniques for the separation of the permanent and the induced magnetic field from the measured magnetic signature of the mock-up model. Also, we describe the prediction method of the induced magnetic field generated from mock-up model using the Magnet s/w, one of the FEM analysis tools for the electro-magnetic field and the magnetic dipole modelling method based on the least square techniques. The proposed modelling and analysis methods can be used for the prediction and the analysis of the static magnetic field generated from the real naval ship as well as the mock-up model.

• Communications of the Korean Mathematical Society
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• 제17권2호
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• pp.363-370
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• 2002

We show that G(x) = $e^{(x}$(1-x))/ -1 is the exponential generating function for the labeled digraphs whose weak components are transitive tournaments and derive both a recursive formula and an explicit formula for the number of them on n vertices. Moreover, we investigate the asymptotic behavior for the coefficients of G(x) using Hayman's method.d.

• 전기의세계
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• 제25권2호
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• pp.40-45
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• 1976

유도전동기의 고주파진동토오크의 산정법에 대하여는 Morrill, Chang, Puchstein Kimball 및 Veinott씨 등에 의한 불평형공간자속분포의 대칭좌표법 또는 2회전자계법해석으로 많은 연구가 거듭되어 기계정수가 고주파토오크에 미치는 영향의 관계를 풀이하고 있다. 또한 Jordan과 Lax씨에 의하여 편심 및 기계적진동에 따른 전자력파의 분포력 mode수 및 그 주파수를 개발함으로서 소음방지대책에 많은 진전을 보았다. 소음진동측정방법으로는 원래 진동측정이 정밀한 장치에 의존하여야 하며 그 방법 또한 어려운 점이 많아 method of 1-point measurement of electromagnetic-force waves로 처리되어 왔으나 요즈음에는 anechoic chamber와 같은 장치에서의 특별한 조작에 의하여 method of resultant measurement of accoustic noise powers에 의하여 보다 합리적인 소음측정 및 해석이 가능하게 되었다.

• Proceedings of the KIEE Conference
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• 대한전기학회 1998년도 하계학술대회 논문집 C
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• pp.935-938
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• 1998

This paper presents the method of load management to measure the winter season's load characteristics of distribution pole transformers. The proposed load model constructed used by the quadratic load correlation coefficients. To verify the estimated model, we compared with linear model by calculation results. The results can contribute an improvement of conventional load management method.

• Proceedings of the KIEE Conference
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.1506-1507
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• 2007

For GPR applications, accurate analysis of the scatterered field is necessary to identify the unknown target. Dyadic Green's Function of the multilayered medium is developed and applied to analyse of underground conduting object. We used method of moment(MOM) with dyadic Green's function, and Discrete Complex Image Method(DCIM).