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41.
Nonlinear Dynamics - Escape from a potential well is an extreme example of transient behavior. We consider the escape of the harmonically forced particle under viscous damping from the benchmark... 相似文献
42.
Ponomarev A. N. Barabashko M. S. Rezvanova A. E. Evtushenko E. P. 《Russian Physics Journal》2021,63(11):1885-1890
Russian Physics Journal - The paper analyzes the influence of porosity of hydroxyapatite (HA)/multi-wall carbon nanotubes (MWCNTs) composites on their fracture toughness. It is found that two... 相似文献
43.
International Applied Mechanics - Quaternion attitude determination algorithms based on vector measurements are proposed. The projections of the normalized vectors in the reference and the... 相似文献
44.
Voitsekhovskii A. V. Nesmelov S. N. Dzyadukh S. M. Kopylova T. N. Degtyarenko K. M. 《Russian Physics Journal》2021,64(7):1281-1288
Russian Physics Journal - Experimental studies of the admittance of MIS structures based on pentacene with a two-layer insulator SiO2–Al2O3 and back contacts made of various materials (Au,... 相似文献
45.
Studying the vibrational behavior of feed drive systems is important for enhancing the structural performance of computer numerical control (CNC) machines. The preload on the screw and nut position have a great influence on the vibration characteristics of the feed drive as two very important operational conditions. Rotational acceleration of the screw also affects the performance of the CNC feed drive when machining small parts. This paper investigates the influence of preload and nut position on the vibration characteristics of the feed drive system of a CNC metal cutting machine in order to be able to eliminate an observed resonance occurred at high rotational speeds of the screw, corresponding to high feed rates. Additionally, rational structural parameters of the feed drive system are selected in order to increase the rotational acceleration for improving the performance of the CNC machine. Experiments and analyses showed that by selecting specific parameters of feed drive system and simultaneously applying a certain value of preload, a 97% increase in rotational acceleration and 30% time reduction considering the vibration resistance at high rotational speeds can be achieved. 相似文献
46.
Crystallography Reports - It is shown by the example of hydrogen (in hydrides ZrH), helium (in pores after implantation), and nickel (in G-phase precipitates) that the application of electron... 相似文献
47.
Aitken R. Alan Inwood Ryan A. Slawin Alexandra M. Z. 《Journal of chemical crystallography》2021,51(4):497-504
Journal of Chemical Crystallography - Molecular structures of (R)-2,2′-dimethyl-1,1′-binaphthyl [monoclinic, a?=?11.24420 (11), b?=?10.56190 (9),... 相似文献
48.
Machado J. A. Tenreiro Rocha-Neves J. M. Azevedo Filipe Andrade J. P. 《Nonlinear dynamics》2021,106(2):1525-1555
Nonlinear Dynamics - Given a data-set of Ribonucleic acid (RNA) sequences we can infer the phylogenetics of the samples and tackle the information for scientific purposes. Based on current data and... 相似文献
49.
Zayed Elsayed M. E. Shohib Reham M. A. Alngar Mohamed E. M. Yıldırım Yakup 《Computational Mathematics and Modeling》2021,32(2):235-252
Computational Mathematics and Modeling - Based on the extended simplest equation method, we construct solitons and other solutions for the nonlinear convection-diffusion-reaction equation with... 相似文献
50.
Mechanics of Composite Materials - The paper presents results of changes in the extreme values (minimum and maximum possible) of the tensile strength of threads and single filaments of an aramid... 相似文献