Shock Absorption Effect of Semi-active Mass Control Mechanism for Structure

Author(s):  
Ming-Hsiang Shih ◽  
Wen-Pei Sung
2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Xiaoying Liu ◽  
Yong Yue ◽  
Xuyang Wu ◽  
Yanhua Hao ◽  
Yong Lu

On the basis of computer aided modeling technology, this paper proposes a porous structure modeling method based on Grasshopper visual programming language and Unigraphics NX (UG) secondary development platform. The finite element model of the foot was established, and then models of shoe soles with four basic porous structures of cross, diamond, star, and x were established. Each structure was set with a cylindrical radius of 1, 2, and 3 mm, and a total of 12 porous structure sole models were established. The shock absorption effect of the sole on the foot was evaluated by the deformation of the sole, the peak plantar pressure, and the peak stress of metatarsal bones. It is found that the maximum value of the sole deformation of the diamond porous sole is 4.725 mm, the peak plantar pressure is 105.1 Pa, and the first and second metatarsal peak pressures are 2.230 MPa and 3.407 MPa, which have the best shock absorption effect. It shows that the porous structure plays an important role in the cushioning of the sole. The biomechanical effects of porous soles on feet are studied by computer-aided technology and finite element analysis. This study provides a new research method for the cushioning design of shoe soles and has important reference value for the design of footwear.


2019 ◽  
Vol 16 (4) ◽  
pp. 625-645
Author(s):  
Haixu Yang ◽  
Feng Zhu ◽  
Haibiao Wang ◽  
Liang Yu ◽  
Ming Shi

Purpose The purpose of this paper is to describe the structure of nonlinear dampers and the dynamic equations, and nonlinear realization principles and optimize the parameters of nonlinear dampers. Using the finite element method to analyze the seismic performance of the frame structure with shock absorber. Design/methodology/approach The nonlinear shock absorber was installed in a six-storey reinforced concrete frame structure to study its seismic performance. The main structure was designed according to the eight degree seismic fortification intensity, and the time history dynamic analysis was carried out by Abaqus finite element software. EL-Centro, Taft and Wenchuan seismic record were selected to analyze the seismic response of the structure under different magnitudes and different acceleration peaks. Findings Through the principle study and parameter analysis of the nonlinear shock absorber, combined with the finite element simulation results, the shock absorption performance and shock absorption effect of the nonlinear energy sink (NES) nonlinear shock absorber are given as follows: first, the damping of the NES shock absorber is satisfied, and the linear spring stiffness and nonlinear stiffness of the shock absorber are based on the relationship k1=kn×kl2, so that the spring design length is fixed, and the linear stiffness of the shock absorber can be obtained. The nonlinear shock absorber has the characteristics of high rigidity and frequency bandwidth, so that the frequency is infinitely close to the frequency of the main structure, and when the mass of the shock absorber satisfies between 0.056 and 1, a good shock absorption effect can be obtained, and the reinforced concrete with the shock absorber is obtained. The frame structure can effectively reduce the seismic response, increase the natural vibration period of the structure and reduce the damage loss of the structure. Second, the spacer and each additional shock absorber have a small difference in shock absorption effect. After the shock absorber parameters are accurately calculated, the number of installations does not affect the shock absorption effect of the structure. Therefore, the shock absorber is properly constructed and accurately calculated. Parameters can reduce costs. Originality/value New shock absorbers reduce earthquake-induced damage to buildings.


2007 ◽  
Vol 23 (2) ◽  
pp. 119-127 ◽  
Author(s):  
Hung-Ta Chiu ◽  
Tzyy-Yuang Shiang

The purpose of this study was to investigate the effects of insoles and additional shock absorption foam on the cushioning properties of various sport shoes with an impact testing method. Three commercial sport shoes were used in this study, and shock absorption foam (TPE5020; Vers Tech Science Co. Ltd., Taiwan) with 2-mm thickness was placed below the insole in the heel region for each shoe. Eight total impacts with potential energy ranged from 1.82 to 6.08 J were performed onto the heel region of the shoe. The order of testing conditions was first without insole, then with insole, and finally interposing the shock absorption foam for each shoe. Peak deceleration of the striker was measured with an accelerometer attached to the striker during impact. The results of this study seemed to show that the insole or additional shock absorption foam could perform its shock absorption effect well for the shoes with limited midsole cushioning. Further, our findings showed that insoles absorbed more, even up to 24–32% of impact energy under low impact energy. It seemed to indicate that insoles play a more important role in cushioning properties of sport shoes under a low impact energy condition.


Author(s):  
Edna S. Kaneshiro

It is currently believed that ciliary beating results from microtubule sliding which is restricted in regions to cause bending. Cilia beat can be modified to bring about changes in beat frequency, cessation of beat and reversal in beat direction. In ciliated protozoans these modifications which determine swimming behavior have been shown to be related to intracellular (intraciliary) Ca2+ concentrations. The Ca2+ levels are in turn governed by the surface ciliary membrane which exhibits increased Ca2+ conductance (permeability) in response to depolarization. Mutants with altered behaviors have been isolated. Pawn mutants fail to exhibit reversal of the effective stroke of ciliary beat and therefore cannot swim backward. They lack the increased inward Ca2+ current in response to depolarizing stimuli. Both normal and pawn Paramecium made leaky to Ca2+ by Triton extrac¬tion of the surface membrane exhibit backward swimming only in reactivating solutions containing greater than IO-6 M Ca2+ Thus in pawns the ciliary reversal mechanism itself is left operational and only the control mechanism at the membrane is affected. The topographic location of voltage-dependent Ca2+ channels has been identified as a component of the ciliary mem¬brane since the inward Ca2+ conductance response is eliminated by deciliation and the return of the response occurs during cilia regeneration. Since the ciliary membrane has been impli¬cated in the control of Ca2+ levels in the cilium and therefore is the site of at least one kind of control of microtubule sliding, we have focused our attention on understanding the structure and function of the membrane.


1974 ◽  
Vol 32 (01) ◽  
pp. 057-064 ◽  
Author(s):  
Y Nemerson ◽  
S.A Silverberg ◽  
J Jesty

SummaryTwo reactions of the extrinsic pathway of coagulation, the activations of Factor X and prothrombin, have been studied in purified systems and shown to be self-damping. Factor X was activated by the tissue factor - Factor VII complex, and prothrombin by two systems: the coagulant protein of Taipan venom, and the physiological complex of activated Factor X, Factor V, lipid, and calcium ions. In each case the yield of enzyme, activated Factor X or thrombin, is a function of the concentration of activator. These and other observations are considered as a basis for a control mechanism in coagulation.


2010 ◽  
Vol 4 (1) ◽  
pp. 42-59 ◽  
Author(s):  
Kane X. Faucher

The popularity of Deleuze and Guattari is an undeniable precedent in current theoretical exchanges, and it could be stated without much contention that one's theoretical positioning must at some point deal with the salient conceptual offerings of Deleuze and Guattari, especially their double-opus, Anti-Oedipus and A Thousand Plateaus wherein a wealth of critique abounds. However, the significant trends concerning Deleuze and Guattari ‘scholarship’ may be jeopardised by the (ab)use of certain conceptual themes and methods in their work that are distorted and employed by big business looking to secure their legacies of power by means of a control mechanism that looks to subjugate an entire world by means of (to borrow a term from Mihai Spariosu) ‘globalitarianism’. Our aim here will be to use McDonald's Corporation as an example of how the theoretical offerings of Deleuze and Guattari have been indirectly and hastily deployed for corporate ends, how these attempts are counter-Deleuzian, and to answer at least one of Žižek's criticisms against Deleuze.


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