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51.
    
In this paper, we present a new algorithm to solve a kind of nonlinear time space-fractional partial differential equations on a finite domain. The method is based on B-spline wavelets approximations, some of these functions are reshaped to satisfy on boundary conditions exactly. The Adams fractional method is used to reduce the problem to a system of equations. By multiscale method this system is divided into some smaller systems which have less computations. We get an approximated solution which is more accurate on some subdomains by combining the solutions of these systems. Illustrative examples are included to demonstrate the validity and applicability of our proposed technique, also the stability of the method is discussed.   相似文献   
52.
    
Tele-medical information system provides an efficient and convenient way to connect patients at home with medical personnel in clinical centers. In this system, service providers consider user authentication as a critical requirement. To address this crucial requirement, various types of validation and key agreement protocols have been employed. The main problem with the two-way authentication of patients and medical servers is not built with thorough and comprehensive analysis that makes the protocol design yet has flaws. This paper analyzes carefully all aspects of security requirements including the perfect forward secrecy in order to develop an efficient and robust lightweight authentication and key agreement protocol. The secureness of the proposed protocol undergoes an informal analysis, whose findings show that different security features are provided, including perfect forward secrecy and a resistance to DoS attacks. Furthermore, it is simulated and formally analyzed using Scyther tool. Simulation results indicate the protocol’s robustness, both in perfect forward security and against various attacks. In addition, the proposed protocol was compared with those of other related protocols in term of time complexity and communication cost. The time complexity of the proposed protocol only involves time of performing a hash function Th, i.e.,: O(12Th). Average time required for executing the authentication is 0.006 seconds; with number of bit exchange is 704, both values are the lowest among the other protocols. The results of the comparison point to a superior performance by the proposed protocol.  相似文献   
53.
Journal of Mechanical Science and Technology - An adaptive Finite element analysis (FEA) was proposed in this paper for the industrial design of bimetal conical-cylindrical cup hydroforming....  相似文献   
54.
Many countries have experienced restructuring in their electric utilities. This restructuring has presented the power industries with new challenges, the most important of which is long-term investment planning under uncertain conditions. This paper presents an improved mechanism for capacity payment. The mechanism has been investigated based on system dynamic modeling. In our proposed mechanism, generators will recover a part of their investment through capacity payment. While the payment for any plant remains constant during the operation period, it depends on the investment needed to build it. The main factors affecting long-term planning have been considered in our model. The approach can be used to investigate the effects of fixed as well as variable capacity payment in market investment. We used the probability density function of load as a new concept to calculate average market price. Delays in unit constructions, estimation of demand, and market capacity growth during construction periods have been included in the proposed algorithm as parameters, which affect the regulator's decision for changing capacity payment. The model can be used by regulators to investigate strategies that may affect the fluctuations in the market.  相似文献   
55.
Theoretical Foundations of Chemical Engineering - This study mathematically models the solubility of hydrogen sulfide in ten ionic liquids including 1-(2-hydroxyethyl)-3-imidazolium [Hoemim]+ with...  相似文献   
56.
Li  Hong Xian  Zhang  Yitao  Edwards  David  Hosseini  M. Reza 《Building Simulation》2020,13(2):475-487
Building Simulation - Australia is receiving an average of 58 million PJ of solar radiation per year, which is about 1000 times larger than its total energy generation. Roof-top solar photovoltaic...  相似文献   
57.
Wireless Networks - Aggregation of resources in space, spectrum, and so on, is the fundamental idea behind many technology building blocks of 5G networks, such as massive multi-input multi-output...  相似文献   
58.
Laminar mixed convection of a nanofluid consisting of water and Al2O3 in an inclined tube with heating at the top half surface of a copper tube has been studied numerically. The bottom half of the tube wall is assumed to be adiabatic (presenting a tube of a solar collector). Heat conduction mechanism through the tube wall is considered. Three-dimensional governing equations with using two-phase mixture model have been solved to investigate hydrodynamic and thermal behaviours of the nanofluid over wide range of nanoparticle volume fractions. For a given nanoparticle mean diameter the effects of nanoparticle volume fractions on the hydrodynamics and thermal parameters are presented and discussed at different Richardson numbers and different tube inclinations. Significant augmentation on the heat transfer coefficient as well as on the wall shear stress is seen.  相似文献   
59.
Sn/Pt/Na-ZSM-5 was used as catalyst for the dehydrogenation of isobutane, and the effect of SiO2/Al2O3 ratio and the dispersion of Pt nanoparticles on the conversion and product selectivity were studied under atmospheric pressure at 848 K. The catalysts were characterized by various techniques such as H2 chemisorption, TEM, SEM, EDX, XRD, FT-IR, TG/DTG, elemental analysis by XRF and ICP techniques. Higher dispersion of Pt nanoparticles in the catalyst with SiO2/Al2O3 ratio of 40 resulted in higher selectivity for isobutene.  相似文献   
60.
Solubility of carbon monoxide in water is very important for its biological oxidation or removal process of gaseous pollutants. Present research shows the effect of pressure on solubility of carbon monoxide in liquid phase and its removal process by a biofilter. The results are considered as laboratory research on carbon monoxide elimination. In this method a pressurized trickle-bed biofilter was used to increase pressure in the reactor. The biofilter was filled with Leca-stones and inoculated with microorganisms. When the system’s pressure is increased, the solubility of carbon monoxide will be increased, respectively, and it causes a better reaction of the microorganisms for removing of gaseous pollutants. The efficiency was improved significantly by increasing the pressure in the reactor.  相似文献   
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