• Title/Summary/Keyword: wave-energy

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Effects of Ultrasonic Energy on Mn-Zn Ferrite Powder Behavior (초음파 에너지가 mn-Zn Ferrite 분체에 미치는 영향)

  • 이경직;이대희;이석기;이병교
    • Journal of the Korean Ceramic Society
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    • v.36 no.7
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    • pp.751-755
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    • 1999
  • Effect of ultrasonic-wave irradiation on the Mn-Zn ferrite powder suspension prepared by solid-state reaction and alcoholic dehydration methods was investigated. Size distribution and morphology of the powders prepared at different temperature were examined as a function of irradiation time. It was observed that the powders were reduced in size by ultrasonic energy through distinct routes.

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Analysis of wave motion in micropolar transversely isotropic thermoelastic half space without energy dissipation

  • Kumar, Rajneesh;Gupta, Rajani Rani
    • Interaction and multiscale mechanics
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    • v.3 no.2
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    • pp.145-156
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    • 2010
  • The propagation of waves in a micropolar transversely isotropic half space in the theory of thermoelasticity without energy dissipation are discussed. After developing the solution, the phase velocities and attenuation quality factor has been obtained. The expressions for amplitudes of stresses, displacements, microrotation and temperature distribution have been derived and computed numerically. The numerical results have been plotted graphically.

A CLOSED-FORM SOLUTION FOR TURBULENT WAVE BOUNDARY LAYERS

  • Larson, Magnus
    • Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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    • 1995.10a
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    • pp.66-70
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    • 1995
  • The oscillatory boundary layer that develops when surface waves propagate over the sea bottom affects many flow-pendent phenomena in the coastal zone. Examples of such phenomena are wave energy dissipation due to bottom friction and the initiation and transport of sediment (Grant and Madsen 1986). In nature the boundary layer under waves will almost always be turbulent (Nielsen 1992). (omitted)

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Motion Analysis of the AWS Wave Energy Device for the Domestic Inshore Environment (국내연안 환경을 고려한 AWS형 파력발전 장치의 움직임 분석)

  • Kim, Jae-Man;Park, Jin-Bae;Choi, Yoon-Ho
    • Proceedings of the KIEE Conference
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    • 2011.07a
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    • pp.1334-1335
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    • 2011
  • 본 논문에서는 국내 연안의 파도특성을 고려한 AWS (Archimedes Wave Swing)형 파력발전 장치의 움직임을 분석한다. 파력발전 장치의 크기 및 설치깊이, 파도 주기에 따른 발전장치의 진폭 변화를 알아보며 최대 진폭을 얻을 수 있도록 발전장치를 모델링한다.

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Load simulation for offshore wind turbine (해상풍력터빈에 대한 하중 모사 방법 연구)

  • Suk, Sangmin;Lee, Sunggun;Chung, Chinhwa;Park, Hyunchul
    • 한국신재생에너지학회:학술대회논문집
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    • 2011.05a
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    • pp.58.1-58.1
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    • 2011
  • In this paper, the purpose is a study on structural analysis for offshore wind turbine using commercial code. Because offshore wind turbine is subjected to great wind and wave force, it is necessary to analyse the dynamics and minimize the response of wind turbine. The offshore wind turbine tower is modelled as a single degree of freedom and multi degree of freedom structure. It is assumed that the blades, nacelle are composed of concentrated masses.

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OBSERVATIONS BY SATELLITE ALTIMETRY OF SHORT SURFACE WAVE ENERGY IN THE DECEMBER 2004 SUMATRA TSUNAMI

  • Gower, Jim
    • Proceedings of the KSRS Conference
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    • v.1
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    • pp.43-46
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    • 2006
  • The main tsunami wave triggered by the December 2004 Sumatra tsunami was detected in the ocean south of India by satellite altimeters on Jason, Topex/Poseidon and Envisat. All three altimeters also detected shorter-wavelength (10 to 100 km), slower-propagating surface waves, spreading from the site of the earthquake. The shorter waves give additional information about the tsunami event, and can be used to better define the generating region in this, and future tsunamis. The properties of the area of shorter tsunami-generated waves may also be important in designing a future satellite-based detection system.

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A Verification of the Numerical Energy Conservation Property of the FD-TD(Finite Difference-Time Domain) Method by Using a Plane Wave Analysis (평면파 해석을 이용한 시간영역-유한차분법의 수치적 에너지 보존성질의 증명)

  • Ihn-Seok Kim
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.7 no.4
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    • pp.320-327
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    • 1996
  • This paper presents that the lossy or amplification property of the Finite Difference-Time Domain(FD-TD) method based on the leap-frog scheme is theoretically verified by using a plane wave analysis. The basic algorithm of the FD-TD method is introduced in order to help understanding the analysis procedure. Since our analysis is formulated by the Von Neumann's approach, the stability inequality is also produced as an another outcome.

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ON THE EXISTENCE OF SOLUTIONS OF QUASILINEAR WAVE EQUATIONS WITH VISCOSITY

  • Park, Jong-Yeoul;Bae, Jeong-Ja
    • Journal of the Korean Mathematical Society
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    • v.37 no.3
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    • pp.339-358
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    • 2000
  • Let be a bonded domain in N with smooth boundary . In this paper, we consider the existence of solutions of the following problem: (1.1)-div{} - + = , , , , , , where q > 1, p$\geq$1, $\delta$>0, , the Laplacian in N and is a positive function like as .

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A note on the wave transformation models analyzing wave energy and phase separately (에너지와 위상을 분리하여 해석하는 파랑변형 모형에 대한 소고)

  • 이창훈;김건우;서경덕
    • Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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    • 2000.09a
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    • pp.149-154
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    • 2000
  • 파랑은 먼바다에서 주로 바람에 의하여 생성되어 천해로 전파되어 오면서 천수, 굴절, 회절, 반사, 중첩의 여러 가지 변형 과정을 거친다. 이 변형 과정 가운데 바닥의 영향으로 발생하는 것은 천수, 굴절, 반사이고 파랑간에 발생하는 것은 회절, 중첩이다. 수심이 파장의 1/2보다 작은 경우 바닥의 영향을 받게 되는데 이 해역이 중간수심해와 천해에 해당한다. 파랑변형모형은 파향선추적법부터 시작된다. (중략)

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