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11.
The basics of acoustic resonance spectroscopy (ARS), which provides data about an object's physical structure and composition, are explained. In ARS, one actively excites a large number of resonances (normal modes) in an object that has no internal vibrations by slowly sweeping the excitation frequency to obtain an acoustic spectrum of the object. The instrumentation for this nondestructive evaluation technique is described, and some applications are briefly discussed 相似文献
12.
Zaleski A. Sinha S.P. Ioannou D.E. Campisi G.J. Hughes H.L. 《Electron Devices, IEEE Transactions on》1995,42(9):1697-1700
By operating one channel of a typical SOI MOSFET in avalanche while keeping the opposite channel accumulated, charge injection into the opposite gate takes place. Three independent experiments are described that demonstrate the occurrence of this opposite-channel based charge injection. The experimental results are in agreement with PISCES numerical simulations 相似文献
13.
A compression moulded Kevlar-phenolic resin composite consisting of 30 wt% continuous fibres was slid against a steel disc such that the fibre axis was normal to the sliding plane. The sliding experiments were conducted in a normal pressure range of 0.47–4.27 MPa and at a sliding speed of 0.5 ms–1. The initial sliding interaction is abrasive. With further sliding, as patches of polymer transfer film develop on the polymer pin and counterface, the interaction becomes adhesive and steady-state friction is established. The wear resistance of the polymer was found to be related to the stability of this film. 相似文献
14.
15.
Sinha Swati Shaw Siddharth Biswas Kunal De Debashis Das Samir Chandra Sarkar Angsuman Bandyopadhyay Jaya 《Microsystem Technologies》2021,27(11):4087-4100
Microsystem Technologies - Single-Walled Carbon Nanotubes (SWCNTs) are widely used as potential carriers in drug delivery systems. The objective of this work was to observe the effects of pristine,... 相似文献
16.
Desulphurization of fifteen US coals of rank ranging from anthracite to sub-bituminous B and five high-temperature chars by carbon monoxide and other gases and gas mixtures between 400 and 600 °C has been studied. The sulphur content of the parent coals ranged between 3.0 and 7.3% and that of the chars between 1.3 and 3.8% by weight. A comparison between air, nitrogen, carbon monoxide, and steam-carbon monoxide mixtures as desulphurizing gases shows the order of desulphurizing ability as . 相似文献
17.
Poly(butylene succinate) and organically modified montmorillonite nanocomposites with there different compositions were prepared via melt blending in a twin‐screw extruder. The structure of the nanocomposites was studied with X‐ray diffraction and transmission electron microscopy, which revealed the formation of intercalated nanocomposites, regardless of the silicate loading. Dynamic mechanical analysis revealed a substantial increase in the storage modulus of the nanocomposites over the entire temperature range investigated. The tensile property measurements showed a relative increase in the stiffness with a simultaneous decrease in the yield strength in comparison with that of neat poly(butylene succinate). The oxygen gas barrier property of neat poly(butylene succinate) improved after nanocomposite preparation with organically modified montmorillonite. The effect of the layered‐silicate loading on the melt‐state linear viscoelastic behavior of the intercalated nanocomposites was also investigated. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 777–785, 2006 相似文献
18.
Full and semi-IPNs were prepared from epoxy and poly methyl methacrylate (PMMA), by the sequential mode of synthesis and were characterized by measurements of ultimate tensile strength (UTS), elongation at break, modulus, and toughness. Aromatic polyamine adducts and ethylene glycol dimethacrylate were used as the crosslinkers for epoxy and comonomer/crosslinker for methyl methacrylate monomer, respectively. Higher UTS and modulus of the semi-IPNs over full IPNs were attributed to the higher probability of interpenetration. The weight retention in the thermal decomposition of the IPNs and semi-IPNs were higher than the epoxy homopolymer. This enhancement was presumably related to the presence of the unzipped methyl methacrylate monomer which acted as radical scavangers in the epoxy degradation. © 1994 John Wiley & Sons, Inc. 相似文献
19.
Nagavarapu Sarat Chandra Vachhani Leena Sinha Arpita Buriuly Somnath 《International Journal of Control, Automation and Systems》2021,19(1):491-504
International Journal of Control, Automation and Systems - The system of multiple agents working in coordination for a given task has several advantages on faster completion, fault-tolerance, etc.... 相似文献
20.
Detailed Real-Time Urban 3D Reconstruction from Video 总被引:2,自引:0,他引:2
M. Pollefeys D. Nistér J.-M. Frahm A. Akbarzadeh P. Mordohai B. Clipp C. Engels D. Gallup S.-J. Kim P. Merrell C. Salmi S. Sinha B. Talton L. Wang Q. Yang H. Stewénius R. Yang G. Welch H. Towles 《International Journal of Computer Vision》2008,78(2-3):143-167
The paper presents a system for automatic, geo-registered, real-time 3D reconstruction from video of urban scenes. The system
collects video streams, as well as GPS and inertia measurements in order to place the reconstructed models in geo-registered
coordinates. It is designed using current state of the art real-time modules for all processing steps. It employs commodity
graphics hardware and standard CPU’s to achieve real-time performance. We present the main considerations in designing the
system and the steps of the processing pipeline. Our system extends existing algorithms to meet the robustness and variability
necessary to operate out of the lab. To account for the large dynamic range of outdoor videos the processing pipeline estimates
global camera gain changes in the feature tracking stage and efficiently compensates for these in stereo estimation without
impacting the real-time performance. The required accuracy for many applications is achieved with a two-step stereo reconstruction
process exploiting the redundancy across frames. We show results on real video sequences comprising hundreds of thousands
of frames. 相似文献