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201.
Pham Dinh Tuan 《时间序列分析杂志》1984,5(4):273-279
Abstract. Several recursive relations concerning some statistics useful in identifying the order of autoregressive moving average are derived and the asymptotic behaviour of these statistics are studied. 相似文献
202.
A modified numerical method is introduced to study the interaction between the heat and dynamic response of viscoelastic bodies with temperature-dependent properties. The method is applied to calculate the stress and temperature distributions in a viscoelastic cylinder subjected to cyclic internal pressures. It is found that a large temperature rise may occur due to the interaction, where the value depends upon the thermal and mechanical properties of the material, cylinder size and the frequency of the applied pressure. 相似文献
203.
This study focuses on the design of robust nonlinear controllers based on both conventional and hierarchical sliding mode techniques for double-pendulum overhead crane systems. In the first approach, a first-order sliding surface is provided and a proper control scheme is generated to stabilize the surface. In the second approach, two levels of sliding surfaces are proposed and the control scheme is designed based on the stability of the second-level surface. We also prove the stability of the first-level sliding surface. To verify the quality of the proposed controllers, simulation for a particular type of overhead crane systems is implemented. Simulation results show that all state trajectories asymptotically converged to desired values. 相似文献
204.
Based on Reddy’s third-order shear deformation plate theory, the nonlinear dynamic response and vibration of imperfect functionally graded carbon nanotube-reinforced composite (FG-CNTRC) plates on elastic foundations subjected to dynamic loads and temperature are presented. The plates are reinforced by single-walled carbon nanotubes which vary according to the linear functions of the plate thickness. The plate’s effective material properties are assumed to depend on temperature and estimated through the rule of mixture. By applying the Airy stress function, Galerkin method and fourth-order Runge–Kutta method, nonlinear dynamic response and natural frequency for imperfect FG-CNTRC plates are determined. In numerical results, the influences of geometrical parameters, elastic foundations, initial imperfection, dynamic loads, temperature increment, and nanotube volume fraction on the nonlinear vibration of FG-CNTRC plates are investigated. The obtained results are validated by comparing with those of other authors. 相似文献
205.
Pham Hai Chien Pedro Akeem Le Quang Tuan Lee Do-Yeop Park Chan-Sik 《Universal Access in the Information Society》2019,18(2):269-285
Universal Access in the Information Society - In order to proactively prevent accidents and injuries in construction, tertiary safety education should equip students with adequate safety knowledge... 相似文献
206.
207.
Xuan Nui Pham Dinh Linh Tran Tuan Dat Pham Quang Man Nguyen Van Thi Tran Thi Huan Doan Van 《Advanced Powder Technology》2018,29(1):58-65
Keggin-type 12-tungstophosphoric [PW12O40]3? heteropolyanions were successfully immobilized onto mesoporous material surface of SBA-15 functionalized using the (3-aminopropyl)triethoxysilane (APTES) synthesized by one-pot co-condensation method, also called one-step synthesis. The synthesized PW?-NH3+-SBA-15 catalyst was characterized by XRD, N2 adsorption–desorption, FT-IR, TGA, SEM, TEM, EDS, XPS methods. The results indicated that ordered hexagonal mesostructure for SBA-15 support was still maintained after being functionalized with amine groups, while the specific surface area of SBA-15 was decreased. The active species of phosphotungstic acid H3PW12O40 (HPW) retained its Keggin structure of the heteropolyanions on the amine-modified SBA-15. The PW?–+H3N–SBA–15 catalyst exhibited a high catalytic activity for oxidative desulfurization process of sulfur-containing model fuel. The dibenzothiophene (DBT) conversion of almost 100% was achieved with reaction conditions of 40?mg of catalyst dosage, 2?mL of hydrogen peroxide, 90?°C of reaction temperature, and 120?min of reaction time. 相似文献
208.
Wang Lang Lu Zhe-Ming Ma Long-Hua Feng Ya-Pei 《Multimedia Tools and Applications》2018,77(7):8495-8510
Multimedia Tools and Applications - Vector quantization (VQ) has been successfully used in data compression and feature extraction areas. Codebook design is the essential step of VQ. The K-means... 相似文献
209.
Wireless Networks - This paper studies the secrecy performance of a wireless energy harvesting system in which a source connected to wireless backhaul links sends information to a destination via... 相似文献
210.
Tuan Tran 《Virtual and Physical Prototyping》2017,12(4):333-334
A timely book, titled ‘Standards, Quality Control, and Measurement Sciences in 3D Printing and Additive Manufacturing’ has been published to discuss the bottleneck issues when adopting 3D printing in manufacturing. This book review provides some personal thoughts and discussions on the new book. 相似文献