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1.
Anton Glushchenko Vladislav Petrov Konstantin Lastochkin 《International Journal of Adaptive Control and Signal Processing》2021,35(6):1120-1137
The scope of this research is a problem of parameters identification of a linear time-invariant plant, which (1) input signal is not frequency-rich, (2) is subjected to initial conditions and external disturbances. The memory regressor extension (MRE) scheme, in which a specially derived differential equation is used as a filter, is applied to solve the above-stated problem. Such a filter allows us to obtain a bounded regressor value, for which a condition of the initial excitation (IE) is met. Using the MRE scheme, the recursive least-squares method with the forgetting factor is used to derive an adaptation law. The following properties have been proved for the proposed approach. If the IE condition is met, then: (1) the parameter error of identification is bounded and converges to zero exponentially (if there are no external disturbances) or to a set (in the case of them) with an adjustable rate, (2) the parameters adaptation rate is a finite value. The above-mentioned properties are mathematically proved and demonstrated via simulation experiments. 相似文献
2.
Raul D. Rodriguez Sergey Shchadenko Gennadiy Murastov Anna Lipovka Maxim Fatkullin Ilia Petrov Tuan-Hoang Tran Alimzhan Khalelov Muhammad Saqib Nelson E. Villa Vladimir Bogoslovskiy Yan Wang Chang-Gang Hu Alexey Zinovyev Wenbo Sheng Jin-Ju Chen Ihsan Amin Evgeniya Sheremet 《Advanced functional materials》2021,31(17):2008818
Polyethylene terephthalate (PET) is the most widely used polymer in the world. For the first time, the laser-driven integration of aluminum nanoparticles (Al NPs) into PET to realize a laser-induced graphene/Al NPs/polymer composite, which demonstrates excellent toughness and high electrical conductivity with the formation of aluminum carbide into the polymer is shown. The conductive structures show an impressive mechanical resistance against >10000 bending cycles, projectile impact, hammering, abrasion, and structural and chemical stability when in contact with different solvents (ethanol, water, and aqueous electrolytes). Devices including thermal heaters, carbon electrodes for energy storage, electrochemical and bending sensors show this technology's practical application for ultra-robust polymer electronics. This laser-based technology can be extended to integrating other nanomaterials and create hybrid graphene-based structures with excellent properties in a wide range of flexible electronics’ applications. 相似文献
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Gitis V. G. Derendyaev A. B. Petrov K. N. Weinstock A. P. Dumanskaya I. O. Zatsepa S. N. Zelenko A. A. Ivchenko A. A. Nesterov E. S. 《Journal of Communications Technology and Electronics》2018,63(6):691-705
Journal of Communications Technology and Electronics - A new geoinformation technology for monitoring the hydrometeorological situation in the Arctic is considered. This technology combines two... 相似文献
4.
Petrov S. N. Drozdova N. F. Fedoseev M. L. Mikhailov M. S. Svyatysheva E. V. Islamov A. Kh. 《Metal Science and Heat Treatment》2020,62(1-2):95-102
Metal Science and Heat Treatment - The size and volume fraction of fine particles of secondary β -phase formed during hardening heat treatment of pseudo-β-titanium alloy VT22 are... 相似文献
5.
Kondrat’ev S. Yu. Petrov S. N. Anastasiadi G. P. Tsemenko A. V. 《Metal Science and Heat Treatment》2020,62(1-2):35-45
Metal Science and Heat Treatment - Optical and electron microscopy, x-ray spectral microanalysis, and thermogravimetric analysis in combination with differential scanning calorimetry are used to... 相似文献
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Xixiang Zhu Hengxing Xu Yongtao Liu Jia Zhang Miaosheng Wang Ilia N. Ivanov Olga S. Ovchinnikova Bin Hu 《Advanced materials (Deerfield Beach, Fla.)》2019,31(49)
A new approach to generate a two‐photon up‐conversion photoluminescence (PL) by directly exciting the gap states with continuous‐wave (CW) infrared photoexcitation in solution‐processing quasi‐2D perovskite films [(PEA)2(MA)4Pb5Br16 with n = 5] is reported. Specifically, a visible PL peaked at 520 nm is observed with the quadratic power dependence by exciting the gap states with CW 980 nm laser excitation, indicating a two‐photon up‐conversion PL occurring in quasi‐2D perovskite films. Decreasing the gap states by reducing the n value leads to a dramatic decrease in the two‐photon up‐conversion PL signal. This confirms that the gap states are indeed responsible for generating the two‐photon up‐conversion PL in quasi‐2D perovskites. Furthermore, mechanical scratching indicates that the different‐n‐value nanoplates are essentially uniformly formed in the quasi‐2D perovskite films toward generating multi‐photon up‐conversion light emission. More importantly, the two‐photon up‐conversion PL is found to be sensitive to an external magnetic field, indicating that the gap states are essentially formed as spatially extended states ready for multi‐photon excitation. Polarization‐dependent up‐conversion PL studies reveal that the gap states experience the orbit–orbit interaction through Coulomb polarization to form spatially extended states toward developing multi‐photon up‐conversion light emission in quasi‐2D perovskites. 相似文献
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