• Title/Summary/Keyword: BEM method

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Design of Interference Type Noise Barrier Using the BEM (경계요소법을 이용한 간섭형 방음벽의 설계)

  • 이상권;이승영
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.13 no.11
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    • pp.831-837
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    • 2003
  • This paper investigates the insertion loss of nosie barrier with a interference device, The efficiency of the conventional interference-type noise barrier depends on specific frequency, Thus this study is performed to improve the efficiency of the nosie barrierin the range of broadband frequency. by changing the shape of interference device and adding the channel with various depths, The boundary element method (BEM) is used to predict the insertion loss of noise barrier. Two-dimensional boundary element model is created to simulate the performance of long barrier with a line source.

Design of Interference Type Noise Barrier Using The BEM (경계요소법을 이용한 간섭형 방음벽의 설계)

  • Lee, Seung-Young;Lee, Sang-Kwon;Cho, Sung-Hwan
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.11b
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    • pp.749-754
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    • 2002
  • This paper investigates the insertion loss of nosie barrier with a interference device. The efficiency of the conventional interference-type noise barrier depends on specific frequency. Thus this study is performed to improve the efficiency of the nosie barrier in the range of broadband frequency, by changing the shape of interference device and adding the channel with various depths. The boundary element method (BEM) is used to predict the insertion loss of noise barrier. Two-dimensional boundary element model is created to simulate the performance of long barrier with a line source.

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Suppression of Sound Radiation from Composite Plate Structures Using Piezoelectric Materials (압전재료를 이용한 복합재료 평판 구조물의 음향파워 억제)

  • 윤기원;김승조
    • Journal of KSNVE
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    • v.6 no.6
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    • pp.781-790
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    • 1996
  • The goal of current research is to suppress the acoustic noise radiated from vibration of composite plate structure. The induced noise can be reduced through the control of the corresponding structural vibration modes by using the piezoelectric materials as actuator. The acoustic fields are to be analyzed through the boundary element method (BEM) based on the Rayleigh intergral equation and structural system through the finite element method (FEM). The suppression of rediated sound is studied by adaping the piezoelectric material as the distributed actuator. Numerical results are presented on the sound radiation from composite plate of arbitrary boundary conditions, the noise reduction adapting the piezoelectric materials as distributed actuator. The results show the effectiveness and possibility of piezoelectric actuator in the control of sound radiation from composite structure.

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Design of Interference Type Noise Barrier Using The BEM (경계요소법을 미용한 간섭형 방음벽의 설계)

  • Lee, Seung-Young;Lee, Sang-Kwon;Cho, Sung-Hwan
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.11a
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    • pp.374.2-374
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    • 2002
  • This paper investigates the insertion loss of nosie barrier with a intereference device. The efficiency of the conventional intereference-type noise barrier depends on specific frequency. Thus this study is performed to improve the efficiency of the rosie barrier in the range of broadband frequency, by changing the shape of intereference device and adding the channel with various depths. The boundary element method (BEM) is used to predict the insertion loss of noise barrier. (omitted)

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Two-dimensional Redistribution of Impurity considering Thermal Oxidation in silicon using BEM (BEM을 이용하여 열산화를 고려한 실리콘 내에서 불순물의 2차원 재분포에 관한 연구)

  • Kim, Hun;Hwang, Ho-Jung
    • Proceedings of the KIEE Conference
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    • 1988.07a
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    • pp.370-374
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    • 1988
  • This paper is concerned with the investigation of the impurity redistribution process in a two step diffusion. In integrated circuit technology, two step boron diffusion involving a deposition step followed by a drive-in step in commonly encounted. The drive-in process is usually performed in oxidizing atmosphere resulting in redistribution of impurity (boron) within the semiconductor. This paper proposes a new numerical analysis method; Bounary Element Method to determine impurity profile at the arbitrary point in domain by its coordinate and boundary value.

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Acoustic Analysis of Unevenly Pitched Fan of Automobile Cooling Pack System (자동차 Cooling Fan용 비등각 축류홴 소음해석)

  • Song, W.-S.;Lee, J.-S.;Kim, J.-Y.;Lee, S.
    • 유체기계공업학회:학술대회논문집
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    • 2004.12a
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    • pp.567-571
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    • 2004
  • The 2-dimensional unsteady flows on and around the cambered airfoils were computed by applying LES with the deductive dynamic SGS model. The unsteady flow field were used as inputs to compute the far-field sounds and directivity patterns from rotating blades by a hybrid approach that exploits Farassat's formula. The BEM (Boundary Element Method) was applied to predict the frequency characteristics from the rotating blades for the cases of even- and uneven-pitched fans. The BEM results suggested that the unevenly pitched fan have less pronounced discrete peaks at BEF frequencies, which was confirmed by the experiment.

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Development of the Analytical Model for Frame Structures using FE-BEM (FE-BEM을 이용한 뼈대구조물의 해석모델 개발(구조 및 재료 \circled1))

  • Choi, Won;Na, Joon-Yeop;Kim, Han-Jung
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 2000.10a
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    • pp.246-252
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    • 2000
  • This paper presents an explanatory study of combining the finite element and boundary element methods to achieve an efficient and accurate analysis of frame structure containing shear wall. This model analyzes the frame by finite element method and the shear wall by boundary element method. The purpose of this study is the specific case that boundary element is surrounded by finite element. If material properties of shear wall are relatively the very smaller than it of frame structure, the displacement shape of each node is calculated exactly. And if the solution of displacement is the larger, the displacement shape is approximated more accurately.

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Analysis and Design of Whole-Head Magnetic Brain Stimulators: A Simulation Study

  • Lee, Chany;Im, Chang-Hwan;Jung, Hyun-Kyo
    • International Journal of Control, Automation, and Systems
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    • v.5 no.3
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    • pp.337-342
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    • 2007
  • This paper proposes a helmet-type whole-head brain stimulator system considering a realistic head geometry. For more accurate design and computer simulations, a realistic volume conductor model was adopted and the current evoked on human cerebral cortex was analyzed using the boundary element method (BEM). To obtain a more focalized evoked current around the target points, various coil configurations were tested and an average targeting error of about 10 mm was obtained.

Computation of Magnetic Thin-Film Head Field with the Boundary Element Method (경계 요소법에 의한 자기 박막 헤드의 자장 계산)

  • Ahn, Chang-Hoi;Lee, Soo-Young;Ra, Jung-Woong
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.26 no.3
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    • pp.50-57
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    • 1989
  • The fringe field of magnetic thin-film head is calculated with the Boundary Element Method (BEM), and the effects of a permeable underlayer to the head field are studied. It is found that the BEM can be efficiently used for this complex problem consisting of three different permeable regions, and the permeable underlayer effectively reduces the length of magnetic flux path and increases the fringe field.

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Analysis of Waveguide Junction in H-Plane Using Finite Element-Boundary Element Method (혼합 유한요소법을 사용한 H평면의 도파관 접합 해석)

  • Jung, Jin-Kyo;Cheon, Chang-Yul;Jung, Hyun-Kyo;Hahn, Song-Yop
    • Proceedings of the KIEE Conference
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    • 1993.07b
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    • pp.663-665
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    • 1993
  • An H-Plane waveguide component with arbitrary shape is analyzed using finite element technique(FEM) cooperated with boundary element method(BEM). For the application of BEM in the waveguide structure, a hybrid ray-mode representation of the waveguide Green's function is used. This technique is applied to the waveguide step load and the computed results are compared with the earlier theoretical results.

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