• Title/Summary/Keyword: element mobility

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Mobility Assessment of Equipment Foundation using Fluid-loaded Whole Ship Model (접수 전선 모델을 이용한 장비 받침대 모빌리티 평가)

  • Lee, Dong-Sup;Cho, Dae-Seung;Kim, Kookhyun
    • Journal of the Society of Naval Architects of Korea
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    • v.51 no.3
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    • pp.179-183
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    • 2014
  • The fluid loading effect has been investigated for the shipboard equipment foundation mobility with finite element model. For the purpose, two kinds of finite element models for 60m class ship have been developed: global and local model. The former is for low frequency range and the latter for middle frequency range. These finite element models contain added mass explaining fluid loading effect. Added mass has been implemented with virtual mass matrix derived from Laplace equation governing fluid surrounding ship hull. The mobility assessment result for diesel generator foundation of the objective model shows that the fluid loading effect should be considered, especially in low frequency range, to more accurately assess shipboard equipment foundation mobility.

Identification of Nuclear Factors that UV-crosslink to Rev-responsive Element RNA (UV조사에 의해 Rev-responsive element RNA와 결합하는 핵단백질인자의 확인)

  • 박희성;남용석
    • Journal of Life Science
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    • v.7 no.3
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    • pp.161-166
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    • 1997
  • HIV-1 Rev protein plays an important role in regulating the expression of viral structural proteins. It allows the nuclear export and accumulation of unspliced and partially spliced viral mRNA in the cytoplasm. The Rev-responsive element RNA, present in the env gene, forms a higly ordered RNA secondary structure and is required for the Rev-mediated mRNA export. For this process to complete factor(s) are strongly suggested. From our experiments of electrophoretic mobility shift, UV-crosslinking and SDS/PAGE, RRE RNA was found to be recognized to several nuclear factors such as 36/37, 56, 41. 76, 150 kD proteins in the order of reactivity. Among them, 36/37 and 56 kD proteins are more reactive upon a brief UV treatment (5 min) and more persistent in the presence of high amount of nonspecific competitor, heparin. Certain nuclear protein9s) seemed to recognize the RRE RNA structure in competition with Rev to gel mobility shift assay.

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Vibration of Pipes Coupled with Internal and External Fluids (내부 및 외부 유체와 연성된 파이프의 진동 해석)

  • Ryue, Jung-Soo
    • The Journal of the Acoustical Society of Korea
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    • v.31 no.3
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    • pp.142-150
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    • 2012
  • The waveguide finite element (WFE) method is a useful numerical technique to investigate wave propagation along waveguide structures which have uniform cross-sections along the length direction ('x' direction). In the present paper, the vibration and radiated noise of the submerged pipe with fluid is investigated numerically by coupling waveguide finite elements and wavenumber boundary elements. The pipe and internal fluid are modelled with waveguide finite elements and the external fluid with wavenumber boundary elements which are fully coupled. In order to examine this model, the point mobility, dispersion curves and radiated power are calculated and compared for several different coupling conditions between the pipe and internal/external fluids.

Dynamic Analysis of HVAC Case for Passenger Car (승용차용 HVAC Case의 동특성 해석)

  • Yook, Ji-Yong;Cha, Yong-Kil;Lim, Jung-Su;Kim, Kwang-Il;Kim, Sung-Ho
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2008.11a
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    • pp.378-384
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    • 2008
  • This Paper presents dynamic analysis of HVAC(Heating Ventilation & Air Condition) Heater Case which consists of heater and evaporator unit for passenger car. To analyze the dynamic characteristics of HVAC Heater Case. finite element model which consists of shell elements is constructed for modal analysis and experimental Modal analysis has been conducted. Finite element analysis results are compared with experimental results to evaluate of validity of finite element model After identifying node shape and natural frequency of HVAC Heater Case, local stiffness of HVAC Case is evaluated through point mobility using finite element analysis and experiment.

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Dynamic Analysis of HVAC Case for Passenger Car (승용차용 HVAC Case의 동특성 해석)

  • Yook, Ji-Yong;Cha, Yong-Kil;Lim, Jung-Su;Kim, Kwang-Il;Kang, Sung-Ho
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.19 no.1
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    • pp.101-108
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    • 2009
  • This paper presents dynamic analysis of HVAC(heating ventilation & air conditioning) heater case which consists of heater and evaporator unit for passenger car. To analyze the dynamic characteristics of HVAC heater case, finite element model which consists of shell elements is constructed for modal analysis and experimental modal analysis has been conducted. Finite element analysis results are compared with experimental results to evaluate of validity of finite element model. After identifying mode shape and natural frequency of HVAC heater case, local stiffness of HVAC case is evaluated through point mobility using finite element analysis and experiment.

Development of a Criterion for Efficient Numerical Calculation of Structural Vibration Responses

  • Kim, Woonkyung M.;Kim, Jeung-Tae;Kim, Jung-Soo
    • Journal of Mechanical Science and Technology
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    • v.17 no.8
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    • pp.1148-1155
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    • 2003
  • The finite element method is one of the methods widely applied for predicting vibration in mechanical structures. In this paper, the effect of the mesh size of the finite element model on the accuracy of the numerical solutions of the structural vibration problems is investigated with particular focus on obtaining the optimal mesh size with respect to the solution accuracy and computational cost. The vibration response parameters of the natural frequency, modal density, and driving point mobility are discussed. For accurate driving point mobility calculation, the decay method is employed to experimentally determine the internal damping. A uniform plate simply supported at four corners is examined in detail, in which the response parameters are calculated by constructing finite element models with different mesh sizes. The accuracy of the finite element solutions of these parameters is evaluated by comparing with the analytical results as well as estimations based on the statistical energy analysis, or if not available, by testing the numerical convergence. As the mesh size becomes smaller than one quarter of the wavelength of the highest frequency of interest, the solution accuracy improvement is found to be negligible, while the computational cost rapidly increases. For mechanical structures, the finite element analysis with the mesh size of the order of quarter wavelength, combined with the use of the decay method for obtaining internal damping, is found to provide satisfactory predictions for vibration responses.

A Fast Inter-Domain Network-based IP Mobility Scheme for Urban Areas

  • Taghizadeh, Alireza;Wan, Tat-Chee;Budiarto, Rahmat
    • Journal of Communications and Networks
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    • v.16 no.6
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    • pp.645-655
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    • 2014
  • Latency, an identified element of Internet protocol (IP) mobility protocol execution, can reduce handover performance in mobile networks. Although the performance can be improved by applying an effective network-based IP mobility scheme in place of the traditional host-based alternatives, the existing inter-domain extensions of network-based IP mobility continue to suffer from an extended handover latency. This paper proposes a new inter-domain network-based IP mobility scheme based on node movement prediction. The proposed scheme accelerates the handover by preparing the future domain of the mobile node in a proactive manner. Analytical and simulation-based evaluations confirm improved performance of the proposed scheme in terms of handover latency and packet loss compared with existing schemes.

Shock Response Analysis of 2.5in Hard Disk Drive Supported by Rubber Mounts (고무 마운트로 지지된 2.5인치 하드디스크 드라이브의 충격 응답 해석)

  • seol Woong;Chang Young-Bae;Park No-Cheol;Park Young-Pil
    • 정보저장시스템학회:학술대회논문집
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    • 2005.10a
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    • pp.215-216
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    • 2005
  • Nowadays, mobility as well as basic performances has been the important performance index of hard disk drive, It makes a system unstable to satisfy mobility, huge storage capacity and high transfer rate. Shock and vibration analysis has been important because hard disk drive could be exposed by external shock and vibration. The probability of this situation has been increasing. In this research, each component and the whole system of 2.5in HDD are made to a finite element model. Results of finite element analysis are compared with the results of experimental modal analysis. Shock analysis is executed for 2.5in hard disk drive.

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Flavonoids inhibit the AU-rich element binding of HuC

  • Kwak, Ho-Joong;Jeong, Kyung-Chae;Chae, Min-Ju;Kim, Soo-Youl;Park, Woong-Yang
    • BMB Reports
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    • v.42 no.1
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    • pp.41-46
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    • 2009
  • Post-transcriptional regulation of mRNA stability by Hu proteins is an important mechanism for tumorigenesis. We focused on the molecular interactions between the HuC protein and AU-rich elements (AREs) to find chemical inhibitors of RNA-protein interactions using RNA electrophoretic mobility shift assay with non-radioactive probes. Screening of 52 natural compounds identified 14 candidate compounds that displayed potent inhibitory activity. Six (quercetin, myricetin, (-)-epigallocatechin gallate, ellagic acid, (-)-epicatechin gallate, and rhamnetin) were categorized as phytochemicals, and their $IC_{50}$ values were low ($0.2-1.8\;{\mu}M$).