• Title/Summary/Keyword: radial

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Study of the radial Turbine for Wave Energy Conversion (파력발전용 레이디얼터빈성능에 관한 연구)

  • Kim Tae-Ho;Kim Heuy-Dong;Setoguchi Toshiaki
    • Proceedings of the KSME Conference
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    • 2002.08a
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    • pp.549-552
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    • 2002
  • The objective of this study is to clarify the detailed performances of the impulse type radial turbine and to present an optimum configuration of the turbine. The impulse type radial turbine has been manufactured and investigated experimentally under steady and sinusoidally oscillating flow conditions by model testing. Then, the starting characteristics under sinusoidally flow conditions have been evaluated by a numerical simulation using a quasi-steady analysis. As a result, the running and starting characteristics of the impulse type radial turbine for wave energy conversion have been clarified. Furthermore, the recommended configuration is presented, especially for setting angles of inner and outer guide vanes.

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Radial basis collocation method for dynamic analysis of axially moving beams

  • Wang, Lihua;Chen, Jiun-Shyan;Hu, Hsin-Yun
    • Interaction and multiscale mechanics
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    • v.2 no.4
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    • pp.333-352
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    • 2009
  • We introduce a radial basis collocation method to solve axially moving beam problems which involve $2^{nd}$ order differentiation in time and $4^{th}$ order differentiation in space. The discrete equation is constructed based on the strong form of the governing equation. The employment of multiquadrics radial basis function allows approximation of higher order derivatives in the strong form. Unlike the other approximation functions used in the meshfree methods, such as the moving least-squares approximation, $4^{th}$ order derivative of multiquadrics radial basis function is straightforward. We also show that the standard weighted boundary collocation approach for imposition of boundary conditions in static problems yields significant errors in the transient problems. This inaccuracy in dynamic problems can be corrected by a statically condensed semi-discrete equation resulting from an exact imposition of boundary conditions. The effectiveness of this approach is examined in the numerical examples.

Acoustic Radiation from Radial Vibration Modes of a Thick Annular Disk (후판 환형 디스크 래디얼 모드에 의한 음향방사에 관한 연구)

  • Lee, Hyeongill
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.15 no.4 s.97
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    • pp.412-420
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    • 2005
  • This article proposes analytical solutions for sound radiation from radial vibration modes of a thick annular disk. Structural eigensolutions are calculated using the transfer matrix method. The far-field sound pressure distribution is obtained using two alternate methods. In the first method, pressure is calculated using the Rayleigh integral technique. The second method treats sound radiating radial surfaces as cylindrical radiators of finite length. The Sinc function approach is employed for calculations. Acoustic powers and radiation efficiencies of radial modes are also determined from the far-field sound pressure calculations. Analytical predictions match well with measured data as well as computational results from a finite element code in terms of structural eigensolutions and from a boundary element code in terms of sound pressure, directivity etc.

Dimensions of Structural Elements in Fusiform Ray of Sitka Spruce (Picea sitchensis (Bong.) Carr.) Affecting Radial Permeability

  • Usta, Ilker
    • Journal of the Korean Wood Science and Technology
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    • v.33 no.5 s.133
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    • pp.1-6
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    • 2005
  • The anatomical structure of fusiform ray was examined by scanning electron microscopy (and microscopic images were analysed by image analyser) to explain the differences in radial fluid uptake between the extremes in the radial treatment data, i.e. between the selected trees of QCI (Queen Charlotte Islands in Rhondda, South Wales) and SO (South Oregon in Dalby, North-East England) planted in the UK. The ray structure of these two seed origins was examined microscopically and different patterns of ray composition were observed. The most important anatomical features influencing radial permeability were the nature of fusiform ray, and the condition of the resin canals, epithelial cells and intercellular spaces in particular.

Radial distribution of blue straggler stars in Magellanic Cloud clusters

  • Hong, Jongsuk
    • The Bulletin of The Korean Astronomical Society
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    • v.43 no.1
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    • pp.46.2-46.2
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    • 2018
  • Using the high-resolution observational data obtained by the Hubble Space Telescope, we found that there is the diversity of the radial trends of blue straggler stars (BSSs) in young massive clusters (YMCs) in the Large Magellanic Cloud unlike BSSs in old globular clusters usually showing the segregated radial distributions. To understand the dynamical processes that lead to the none-segregated or even inversely-segregated radial distribution of BSSs, we performed direct N-body simulations for YMCs. Our numerical simulations show that the presence of black hole subsystems inside the cluster centre can significantly affect the dynamical evolution of BSSs and eventually lead to none- or inversely-segregated radial distribution of BSSs.

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An Experimental Study on the Measurement of Radial Directional Natural Frequency in a Passenger Car Tire Roboting under the Load (하중을 받고 회전하는 승용차 타이어의 반경방향 고규진동수 측정에 관한 실험적 연구)

  • Kim, Byoung-Sam;Hong, Dong-Pyo;Chi, Chang-Heon
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.20 no.1
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    • pp.1-13
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    • 1996
  • The measurement of radial directional natural frequency ina passenger car tire rotating under the load is studied. In order to obtain theoretical matural frequency and mode shape, the ploane vibration of a tire is modeled to that of circular beam. By esing the Tieking method based on Hamiltons's principle, theoretical results are determined by considering tension horce due to tire inflation pressure, retational velocity and tangential, radial stiffness. Radial directional modal parameters varying with the inflation pressure, load, rotational velocity are experimentally determined by using frequency response function method. The results show that experimental conditions canbe considered as the parameters which shift the natural frequency.

Two Cases of Radial Nerve Palsy with Chuna Treatment on Cervical Vertebrae (경추 추나치료를 적용한 압박성 요골신경마비 환자 치험 2례)

  • Heo, Su-Young
    • The Journal of Churna Manual Medicine for Spine and Nerves
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    • v.6 no.1
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    • pp.89-96
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    • 2011
  • Objective : The purpose of this study is to evaluate the korean medical treatment for compressive neuropathy of radial nerve, especially chuna treatment of cervical vertebrae. Methods : Two patients were treated with acupuncture and moxibustion, herbal medication, chuna treatment on cervical vertebrae. To evaluate the wrist drop and numbness of hand, Coding Result of arbitrary values and manual muscle test(MMT), visual analogue scale(VAS) were used. Results : After 2 weeks-treatment(in case 1) & 5 weeks-treatment(in case 2), the movement and power of wrist were restored to nearly normal range, also the numbness of hands was removed. All cases show the improvement in the movement of wrist and the numbness of hands. Conclusions : Korean medical treatment including cervical manual therapy as chuna treatment is remarkably effective for radial nerve palsy. But further studies are required to concretely prove the effectiveness of chuna treatment on central vertebrae for peripheral neuropathy.

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The Classification and Frequency Analysis in Radial Pulse (맥파의 인식상의 분류와 주파수 해석)

  • Kil, S.K.;Han, S.H.;Kwon, O.S.;Park, S.H.;Hong, S.H.
    • Proceedings of the KOSOMBE Conference
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    • v.1998 no.11
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    • pp.263-264
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    • 1998
  • In this paper, we present the result of feature points recognition and classification of radial pulse by the shape of pulse wave. And we analyze radial pulse in frequency domain. The recognition algorithm use the method which runs in parallel with both the data of ECG and differential pulse simultaneously to recognize the feature points. Also fie specified 3-time elements of pulse wave as main parameters for diagnosis and measured them by execution of algorithm, then we classify the shape of radial pulse by existence and position of feature points. lastly we execute frequency analysis on the feature points and get the power spectrum of radial pulse.

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A boundary radial point interpolation method (BRPIM) for 2-D structural analyses

  • Gu, Y.T.;Liu, G.R.
    • Structural Engineering and Mechanics
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    • v.15 no.5
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    • pp.535-550
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    • 2003
  • In this paper, a boundary-type meshfree method, the boundary radial point interpolation method (BRPIM), is presented for solving boundary value problems of two-dimensional solid mechanics. In the BRPIM, the boundary of a problem domain is represented by a set of properly scattered nodes. A technique is proposed to construct shape functions using radial functions as basis functions. The shape functions so formulated are proven to possess both delta function property and partitions of unity property. Boundary conditions can be easily implemented as in the conventional Boundary Element Method (BEM). The Boundary Integral Equation (BIE) for 2-D elastostatics is discretized using the radial basis point interpolation. Some important parameters on the performance of the BRPIM are investigated thoroughly. Validity and efficiency of the present BRPIM are demonstrated through a number of numerical examples.

Analysis of Radial Force Density as a Vibration Source in Brushless DC Motor Using 3D Equivalent Magnetic Circuit Network Method (3차원 등가자기회로망법을 이용한 Brushless DC 모터의 진동원으로서의 Radial Force Density 해석)

  • Chun, Y.D.;Hur, J.;Yoon, S.B.;Hong, J.P.;Hyun, D.S.
    • Proceedings of the KIEE Conference
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    • 1997.07a
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    • pp.171-173
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    • 1997
  • This paper presents analysis of the radial force density in brushless DC motor of which distribution is not uniform in the axial direction. The analysis considering 3D shape of teeth and overhang is not only important but essential to calculate the radial force density that acts on the teeth of stator, because it is frequent source of vibration and changes at the end of teeth. For the analysis, a new 3D equivalent magnetic circuit network method taking into account movement of the rotor without remesh is proposed. The radial force density is calculated by Maxwell stress tensor and analyzed by discrete Fourier transform.

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