• Title/Summary/Keyword: acceleration analysis

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Comparison of Mode Superposition Method and Mode Acceleration Method in Dynamic Analysis of Suspension Bridges under Wind Loads (풍하중을 받는 현수교의 진동 해석에 있어서 모우드 중첩법과 모우드 가속도법의 비교)

  • 김태남
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1997.10a
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    • pp.223-230
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    • 1997
  • A method of stochastic dynamic analysis of suspension bridge subjected to random wind loads has been developed in this paper. Example analyses are carried out by mode superposition method(MSM), mode acceleration method(MAM) and advanced mode acceleration method(AMAM) in frequency domain for the Nam-Hae Bridge. In this study the statistical characterics of random wind loads we assumed to be Gaussian stationary zero mean processes. The considered structural response quanties are displacements, shear forces and bending moments. The mean extreme responses are approximately calculated by three times of standard deviations. The followings are the conclusions from this study. 1. Numerical results which obtained by three methods of computer program developed in this paper agree reasonably well when the numbers of modes increase. 2. AMAM is simple, accurate, economic and reliable method compared with the MSM and the MAM.

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Reliability Evaluation on PTC Heater Using Accelerated Life Test and Failure Analysis (고장 분석과 가속 수명시험을 통한 PTC 히터의 신뢰성 평가)

  • Choi, Hyoung-Seuk
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.28 no.12
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    • pp.843-846
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    • 2015
  • In this paper, the failure mechanism of PTC heater were examined closely by failure analysis and based on it, accelerated life test were conducted. Finally, life distribution and acceleration model were established. The failure mechanism of PTC heater such as crack, increase of resistance due to heating were identified. Two acceleration factors such as temperature, humidity were chosen with two levels each and accelerated life test were done. Life distribution were identified as Weibull distribution with shape parameter 5.4 and Temperature-Humidity model was fitted as an acceleration model.

Dynamic Analysis of a Deploying Beam with Geometric Non-Linearity and Translating Acceleration (기하학적 비선형과 이송 가속도를 갖는 전개하는 보의 동적해석)

  • Song, Deok-Ki;Chung, Jin-Tai
    • Proceedings of the KSME Conference
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    • 2001.06b
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    • pp.658-663
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    • 2001
  • The dynamic response of an axially deploying beam is studied when the beam has geometric non-linearity and translating acceleration. Based upon the von Karman strain theory, the governing equations and the boundary conditions of a deploying beam are derived by using extended Hamilton's principle considering the longitudinal and transverse deflections. The equations of motion are discretized by using the Galerkin approximate method. From the discretized equations, the dynamic responses are computed by the Newmark time integration method.

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Design of LNG fuel tank for a light duty truck and numerical analysis of heat leak to LNG tank

  • Alena, Minkasheva;Kim, Sung Joon
    • Journal of Industrial Technology
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    • v.27 no.B
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    • pp.65-70
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    • 2007
  • The LNG tank are properly designed to fit with the limited installation space of a light duty truck, Hyundai Porter II. This designed LNG tank has 36 liter capacity, so two LNG tanks installed on Porter II truck allow it to run about 432 km per fueling. It is almost two times greater than CNG mileage for same truck. To analyze the relationship between car acceleration and heat leak for different fuel vapor/liquid ratios, the modified Fortran program "Pro-Heatleak" is used. Computational analysis shows that the relationship between the heat leak and vapor/liquid ratio is linearly inversed. Heat leak increases with increasing of car acceleration when fuel vapor/liquid ratio is less than 0.5 and decreases when fuel vapor/liquid ratio is greater than 0.5. The difference between maximum and minimum heat leak for full tank is about 12 percents. For the fuel vapor/liquid ratio equal to 0.5 heat leak does not depend on car acceleration.

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A study of acceleration analysis system (가속도 분석 시스템에 관한 연구)

  • Jang, Mi-Ho;Jung, Ho-Young;Cho, Won-Cheol;Lee, Tae-Shik
    • 한국방재학회:학술대회논문집
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    • 2008.02a
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    • pp.601-604
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    • 2008
  • Acceleration analysis system transfers DSS into acceleration value utilizing Quantera that receives the measurement from the accelerometers installed in the whole nation. When earthquake occurs, the system gives accleration values in certain locations in a map where the accelerometers are installed. And it suggests a measure to fix the problems related to abnormal operations of accelerometers.

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The Behaviors of Earthquake Monitoring System for Gyungbu High Speed Railroad on the Odaesan Earthquake (오대산지진 시 경부고속철도 지진감시시스템 거동)

  • Kim, Dae-Sang;Kim, Sung-Il;Choi, Su-Hyun;You, Won-Hee
    • 한국방재학회:학술대회논문집
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    • 2008.02a
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    • pp.537-540
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    • 2008
  • This paper reviews the operation standards and manuals of earthquake monitoring system for Gyungbu high speed railroad. The domestic earthquake monitoring system detects the acceleration data at the locations of lower part of pier and deck of viaducts and bridges, not like foreign system to do the surface ground accelerations. For the purpose of evaluating the behaviors of the domestic earthquake monitoring system, measured acceleration data on the Odaesan earthquake at Iwon viaduct were analysed. The values of maximum acceleration level of the viaduct were increased from 0.0089g(EW component) of the lower part of pier to 0.014g(EW component) on the deck of the viaduct. And also the predominant periods and frequencies were analysed by the frequency domain analysis.

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Stability Analysis of an Mounting Equipment for External Pod on Aircraft by Road Test (항공기 외장형 포드 장착장비의 주행 안정성 분석)

  • Lee, Jong-Hak;Jang, Jong-Youn;Kang, Young-Sik;Choi, Ji-Ho;Kang, Dong-Seok
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2013.10a
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    • pp.424-429
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    • 2013
  • The trolley carrying the pod moves along by the airfield runway. The pod through the trolley are subjected to vibration arising from the ground state, the precision optical components in the pod can have a significant impact. The road tests were conducted by using the measurement pod to remove the risk for the project. The measurement pod was composed with the ACRA, sensors, battery. The accelerometers were attached to get the acceleration through the road condition. The PSD envelop was calculated by FFT from the acceleration. The driving safety was proven through comparing the measurement data and MIL-STD-810G specification.

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Seismic Response Analysis of Freestanding Model of a Spent Fuel Storage Cask (사용후연료 저장용기 자유입상 모델의 지진응답해석)

  • 이재한;서기석;구경회;이홍영;최병일;정성환
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 2003.09a
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    • pp.58-65
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    • 2003
  • The seismic response analysis of a freestanding spent fuel storage cask model are performed for an artificial time history acceleration generated by the basis on the US NRC RG1.60 response acceleration spectrum. This paper focuses on the structural stability by seismic loads to check the overturing possibility of storage cask and the slipping displacement on bed. Parametric analyses of a simplified cask model are performed to take into account the variations in seismic load magnitude and cask/bed interface friction. The analyses results show that the storage cask has a large marginal integrity in the response acceleration and slipping distance for both design seismic and beyond design seismic loads.

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A kinematic analysis of the Thai boxing clinch

  • Trial, William;Wu, Tom
    • Advances in biomechanics and applications
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    • v.1 no.1
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    • pp.57-66
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    • 2014
  • The purpose of the study was to investigate the kinematics between the double collar-tie and double underhook Thai Boxing clinching positions. Ten amateur mixed martial arts athletes executed six knee strikes for both clinching positions with their dominant limb directed towards a target. A standard two-dimensional video motion analysis was conducted, and the results showed a statistical significant difference at the hip joint angle and the angular acceleration of the knee and ankle. Within both clinching positions, there was a statistically significant correlation between the hip and knee joint angles, hip and knee angular velocities, and hip angular acceleration. Between both clinching positions, there was a statistically significant correlation at the knee joint angle, knee angular velocity, and hip angular acceleration. This study demonstrates the importance of the hip and knee joint movements in both clinching positions, which implies the applications of strength training and flexibility at these joints for sports performance and injury prevention. It is suggested that future studies analyzing the non-dominant leg are warranted to fully understand the Thai Boxing clinch.

Analysis of Acceleration Characteristics of a Railgun (레일건 가속특성 분석)

  • Lee, Young-Hyun;Kim, Seong-Ho;Lee, Byung-Ha
    • Journal of the Korea Institute of Military Science and Technology
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    • v.24 no.5
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    • pp.511-518
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    • 2021
  • To accelerate a launch mass with a low level of pressure as possible in a railgun, it is required to hold supplied current nearly constant during launch phase. We obtained the discharging conditions for required current shaping by modeling and analysis of circuit equations coupled to acceleration equation of the launch mass. The acceleration characteristics of the railgun in the conditions were analyzed by comparing experimental and theoretical results.