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排序方式: 共有1191条查询结果,搜索用时 15 毫秒
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Qiang Chenxu Hao Yuxin Zhang Wei Li Jinqiang Yang Shaowu Cao Yuteng 《应用数学和力学(英文版)》2021,42(11):1555-1570
Applied Mathematics and Mechanics - The concept of local resonance phononic crystals proposed in recent years provides a new chance for theoretical and technical breakthroughs in the structural... 相似文献
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Acta Mechanica Sinica - 相似文献
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This paper proposes a generalized dynamics model and a leader-follower control architecture for skid-steered tracked vehicles towing polar sleds. The model couples existing formulations in the literature for the powertrain components with the vehicle-terrain interaction to capture the salient features of terrain trafficability and predict the vehicles response. This coupling is essential for making realistic predictions of the vehicles traversing capabilities due to the power-load relationship at the engine output. The objective of the model is to capture adequate fidelity of the powertrain and off-road vehicle dynamics while minimizing the computational cost for model based design of leader-follower control algorithms. The leader-follower control architecture presented proposes maintaining a flexible formation by using a look-ahead technique along with a way point following strategy. Results simulate one leader-follower tractor pair where the leader is forced to take an abrupt turn and experiences large oscillations of its drawbar arm indicating potential payload instability. However, the follower tractor maintains the flexible formation but keeps its payload stable. This highlights the robustness of the proposed approach where the follower vehicle can reject errors in human leader driving. 相似文献
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Temperature memory effect and its stability revealed via differential scanning calorimetry in ethylene‐vinyl acetate within glass transition range 下载免费PDF全文
Tao Xi Wang Wei Min Huang Hongmei Chen Rui Xiao Hai Bo Lu Shu Feng Kang 《Journal of Polymer Science.Polymer Physics》2016,54(17):1731-1737
In this article, we reveal the temperature memory effect (TME) in a commercial thermoplastic polymer, namely ethylene‐vinyl acetate (EVA), within its glass transition range via a series of differential scanning calorimeter (DSC) tests. In addition, we investigate the influence of heating holding time and also compare the observed TME in current study with that of shape memory alloys (SMAs). It is concluded that the TME via DSC (without any macroscopic shape change) is achievable within the glass transition range of a polymer. Conversely, although the observed TME shares the many similar features as those in SMAs, due to the nature of micro‐Brownian motion in the glass transition of polymers, the resulted TME is strongly affected by the heating holding time. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 1731–1737 相似文献
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AL-Shudeifat Mohammad A. Friswell Michael Shiryayev Oleg Nataraj C. 《Nonlinear dynamics》2020,102(1):129-129
Nonlinear Dynamics - On the title page, author Oleg Shiryavev should be spelled as Oleg Shiryayev. 相似文献
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The importance of thermophoresis and its essential role in particle migration have led to many published reports (i.e. aim and objectives). However, there exists no report on thermo-migration of tiny/nano-sized particles in the motion of various fluids. A meta-analysis on the significance of either nano or tiny particles exposed to thermophoretic force owing to temperature gradient during the dynamics of liquid substances is deliberated upon in this report. The method of slope linear regression through the data point was adopted to scrutinize sixty (60) published reports in which the effects of thermophoresis (thermodiffusion) is deliberated upon. The outcome of the study shows that different responses to the force of a temperature gradient are sufficient enough to enhance the temperature distribution and the concentration of non-Newtonian fluid due to an increase in thermophoresis. Thermophoretic effect increases the concentration of fluids in which the relationship between the shear stress and shear strain is non-linear. Skin friction coefficients is a decreasing function of thermophoresis. Increase in thermophoretic deposition is achievable due to an increase in thermophoresis. The effect of haphazard motion of nanoparticles should be investigated when it increases negligibly and considerably large. Thermal radiation strongly influences the significance of thermo-migration of tiny particles on fluid flow. 相似文献
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Peristaltic flow of non-Newtonian nano fluid through a non-uniform surface has been investigated in this paper. The fluid motion along the wall of the surface is caused by the sinusoidal wave traveling with constant speed. The governing equations are converted into cylindrical coordinate system and assuming low Reynolds number and long wave length partial differential equations are simplified. Analytically solutions of the problem are obtained by utilizing the homotopy perturbation method (HPM). In order to insight the impact of embedded parameters on temperature, concentration and velocity some graphs are plotted for different peristaltic waves. At the end, some observations were made from the graphical presentation that velocity, pressure rise and nano particle concentration are increasing function of thermophoresis parameter Nt while temperature and frictional forces show opposite trend. 相似文献
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