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991.
Wireless Personal Communications - Privacy and security concerns are significant barrier for RFID deployment in many applications in modern day world. The implementation of authentication schemes... 相似文献
992.
Pankaj Kumar Nilesh P. Gurao Arunansu Haldar Satyam Suwas 《Metallurgical and Materials Transactions A》2012,43(6):2043-2055
This article presents the deformation behavior of high-strength pearlitic steel deformed by triaxial compression to achieve
ultra-fine ferrite grain size with fragmented cementite. The consequent evolution of microstructure and texture has been studied
using scanning electron microscopy, electron back-scatter diffraction, and X-ray diffraction. The synergistic effect of diffusion
and deformation leads to the uniform dissolution of cementite at higher temperature. At lower temperature, significant grain
refinement of ferrite phase occurs by deformation and exhibits a characteristic deformation texture. In contrast, the high-temperature
deformed sample shows a weaker texture with cube component for the ferrite phase, indicating the occurrence of recrystallization.
The different mechanisms responsible for the refinement of ferrite as well as the fragmentation of cementite and their interaction
with each other have been analyzed. Viscoplastic self-consistent simulation was employed to understand deformation texture
in the ferrite phase during triaxial compression. 相似文献
993.
S.L. Ashok Kumar M. Saravana Kumar R.P. John P. Thomas Muthiah A. Sreekanth 《Materials science & engineering. C, Materials for biological applications》2013,33(5):2519-2525
1,5-Bis (2-hydroxyacetophenone)thiocarbohydrazone (H4L) has been synthesized and characterized by means of spectroscopic and single crystal X-ray diffraction methods. Interactions of the H4L with a variety of anions were investigated using a combination of UV–visible and fluorescence spectroscopic methods in a biological competing solvent DMSO. The H4L has a high degree of selectivity for fluoride over other anions. 1H NMR titration experiments indicate that a deprotonation process is involved in the chemo sensing process. 相似文献
994.
Kausik Kumar Majumdar D. Dutta Majumder 《International journal of systems science》2013,44(15):889-901
Uncertain information processing by fuzzy if–then rules has received much attention. Here we have taken a different path to model a system, about which we do not have precise information, namely modelling the system by fuzzy-valued functions without resorting to fuzzy if–then rules. As a result, the phase (state) space of the system becomes a fuzzy set and the underlying fuzzy mapping becomes a fuzzy attainability set mapping. Uncertain or fuzzy dynamical systems have been defined in terms of fuzzy attainability set mappings. Fuzzy differentiable dynamical systems have been discussed with a particular emphasis on fuzzy differential inclusion (FDI) relations. An evolutionary algorithm for solving one-dimensional FDIs has been developed. A model of the creation of a tropical cyclone in the form of a vortex, created by winds coming from different directions and colliding under certain conditions, has been proposed in terms of FDIs. A model has been considered for the highly uncertain system of evolution of a tumour in a human body and an FDI relation model of the whole system has been proposed and simulated. The model of an evolution of turbulence, as a random occurrence of vortices in a three-dimensional dynamic fluid, has been proposed and simulated, where each vortex is modelled by a fuzzy-valued function, where uncertain parameter and variable values are fuzzy numbers. All the systems represented by FDI relations have been simulated with the help of the evolutionary algorithm mentioned above. 相似文献
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Ranvir Singh Panwar Suresh Kumar Ratandeep Pandey Om Prakash Pandey 《Tribology Letters》2014,55(1):83-92
In the present work, a detailed study of ceramic reinforcement of different size ranges in the matrix of LM13 alloy on the friction and wear behavior has been carried out. For this purpose, LM13/Zr composite containing 10 wt% zircon sand particles of different size ranges using stir casting process has been developed. Zircon sand particles were incorporated in two ways: firstly as single size reinforcement and secondly dual size reinforcement. Durability of the composites was tested by finding the wear rate of the composite against the steel disk by pin-on-disk method. Addition of zircon sand particles in the LM13 alloy improves the hardness of the composite as well as wear resistance. Wear rate of the developed composites was tested under different test conditions by varying the applied load and ambient temperatures. Wear rate of the composite changes significantly at different ambient temperatures. SEM analysis of the worn surfaces was done to know the operative wear mechanism. 相似文献
1000.
Evaluation of Optimal River Training Work Using GA Based Linked Simulation-Optimization Approach 总被引:1,自引:1,他引:0
Hriday Mani Kalita Arup Kumar Sarma Rajib Kumar Bhattacharjya 《Water Resources Management》2014,28(8):2077-2092
Use of structural measures for controlling a river to minimize its devastating effect and to utilize it for the benefit of mankind is a common practice all over the world. Because of high investment, such measures require prior investigation through model study. As lab based physical model study is very expensive and time consuming, mathematical modeling is generally used for investigating different alternatives of river training works. In this study, a new approach is proposed for deciding appropriate river training measure in a particular reach of a river or channel. In this methodology, an optimization model is linked with the hydrodynamic model for obtaining cost effective combination of groynes which will maintain a user defined flow speed in a pre-decided portion of a river reach. The optimization model is developed using binary coded Genetic Algorithm (GA) and the flow simulation model uses the Beam and Warming scheme for solving the two dimensional (2D) hydrodynamic equations of unsteady flow. The performance of the model is tested by applying the methodology in a rectangular channel for attaining different target speed values at a pre-defined portion of the channel and logical results have been obtained for all the tested scenarios. 相似文献