• Journal of Navigation and Port Research
• /
• v.39 no.5
• /
• pp.385-391
• /
• 2015

In offshore, various external forces such as wind force, tidal current and impulsive breaking wave force act on offshore wind tower. Among these forces, impulsive breaking wave force is especially more powerful than other forces. Therefore, various studies on impulsive breaking wave forces have been carried out, but the soil reaction are incomplete. In this study, the p-y curve is used to calculate the soil reaction acting on the offshore wind tower when an impulsive breaking wave force occurs by typhoon. The calculation of offshore wind tower against impulsive breaking wave force is applied for the multi-layered soil. The results obtained in this study show that although the same wave height is applied, the soil reaction generated by impulsive breaking wave force is greater than the soil reaction generated by wave force.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2014.06a
• /
• pp.253-254
• /
• 2014

In offshore, various external forces such as wind force, wave force and impulsive breaking wave force act on offshore structures. Many researches about this forces are published. Kim and Cao(2008) published researche on wave force of vertical cylinder. Kim and Go(2013) performed research on the subgrade reaction by external forces. Among this forces, impulsive breaking force is more massive than other forces, especially. Therefore, the studies about impulsive breaking wave forces have been carried out. Chun and Shim(1999) analyzed dynamic behavior of cylindrical pile subjected to impulsive breaking wave force. In this study, when the impulsive breaking wave force acts on the offshore wind turbine, the subgrade reaction acting on the mono-pile of the offshore wind turbine is calculated by p-y curve. The calculation is carried out to the multi-layered.

• Journal of the Korean Society for Precision Engineering
• /
• v.25 no.10
• /
• pp.107-114
• /
• 2008

The aim of this study is to obtain the useful design guideline for high impulsive force device with an isolation system by the analytic approach of dynamics characteristics. In this study, the high impulsive force system was modeled and analyzed in view of multi-body dynamics, and verified the modeling and analysis result by the experiment of the high impulsive force device. Additionally, the dynamic analysis was performed for the isolation system with the selected coefficients of elastic spring and damper selected. Experimental result for the high impulsive force device with the isolation system was compared and analyzed. From the result, it was confirmed that the design guideline for the isolation system of the high impulsive force device was useful.

• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.18 no.10
• /
• pp.1024-1032
• /
• 2008

The vibration characteristics of a rotating cantilever beam undergoing impulsive force are investigated using wavelet transformation. The transient response induced by the impulsive force and the rigid body motion of the beam are calculated using hybrid deformation variable modeling along with the Rayleigh-Ritz assumed mode methods. The vibration characteristics of the beam can be analyzed in time-frequency domain with the wavelet transform method. Therefore, the effects of the impulsive force on the transient vibration characteristics of the beam can be investigated more effectively.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2005.05a
• /
• pp.890-895
• /
• 2005

This paper presents the dynamic analysis of a cantilever beam undertaking impulsive force that undergoes rigid body motion. The transient response of the beam induced by the impulsive force and the rigid body motion is calculated based on hybrid deformation variable modeling method by applying the Rayleigh-Ritz assumed mode method. The stiffness variation effect caused by the rigid body motion is considered in this modeling. The effects of the impulsive force position and the angular velocity on the transient responses of the beam are investigated through numerical studies.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2008.04a
• /
• pp.400-406
• /
• 2008

The vibration characteristics of a rotating cantilever beam undergoing impulsive force are investigated using wavelet transformation. The transient response induced by the impulsive force and the rigid body motion of the beam are calculated using hybrid deformation variable modeling along with the Rayleigh-Ritz assumed mode methods. The vibration characteristics of the beam can be analyzed in time-frequency domain with the wavelet transform method. Therefore, the effects of the impulsive force on the transient vibration characteristics of the beam can be investigated more effectively.

• The Journal of the Korea Contents Association
• /
• v.12 no.9
• /
• pp.389-395
• /
• 2012

This research analyzed the peak impulsive force, maximum velocity and a spot of fist's maximum velocity comparing stop-jirugi and push-jirugi. 7 males volunteered for this experiment. peak impulsive force was measured by PS2142 force platform[10], and maximum velocity of fist was measured by PS2103A motion sensor[12]. All of data was collected in the data studio and t-test was applied using SAS 9.1 package. The following conclusions were drawn. First, stop-jirugi's peak impulsive force was greater (P<.01) than that of push-jirugi. Second, push-jirugi's maximum velocity of fist was greater (P<.01) than that of stop-jirugi. Third, stop-jirugi's maximum velocity of fist was occurred on 69.14% of arm's length and that of push-jirugi was occurred on 75.66%. This maximum velocity spot was statistically significant difference(p<.001).

• Transactions of the Korean Society of Automotive Engineers
• /
• v.6 no.3
• /
• pp.169-176
• /
• 1998

A method for the dynamic analysis of multibody systems undertaking impulsive force is introduced in this paper. A partial velocity matrix based on Kane's method is introduced to reduce the number of equations to be solved. Only minimum number of equations of motion can be obtained by using the partial velocity matrix. This reduces the computational effort significantly to obtain the dynamic response of the system. At the very moment of the impulse, instead of using the numerical integrator to solve the equations of motion, the impulse and momentum principle is used to obtain the dynamic response. The impulse as wall as the reaction force acting on the kinematic joints can easily calculated too.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2002.10a
• /
• pp.431-434
• /
• 2002

In this study, the dynamic absorbing system using MR damper for the multiple structure system with high-level-impact force has been investigated. Based on the experiment and analysis of short recoil system, the dynamic absorbing system has been constructed by using MR damper and stroke-dependent variable damper. Through a series of experimental works with the devised test bench, the absorbing system with MR damper using reverse control is effective for reduction of the transmitted force, furthermore, for implementation to the multi-structure impulsive force system.

• Journal of the Computational Structural Engineering Institute of Korea
• /
• v.26 no.5
• /
• pp.359-371
• /
• 2013

This paper is the first paper among two papers which constitute the paper about the rigid body dynamic analysis on the spent nuclear disposal canister under accidental drop and impact on to the ground. This paper performed the general theoretical study on the rigid body dynamic analysis. Through this study the impulsive force which is occurring in the spent nuclear fuel disposal canister under accidental drop and impact to the ground and required for the structural safety design of the canister is intended to be theoretically formulated. The main content of the theoretical study is about the equation of motion in the multibody dynamics. On the basis of this study the impulsive force which is occurring in the multibody in the case of collision between multibody is theoretically formulated. The application of this theoretically formulated impulsive force to computing the impulsive force occurring in the spent nuclear fuel disposal canister under accidental drop and impact to the ground is investigated.