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41.
Composite membranes based on polyvinyl chloride and acrylonitrile butadiene styrene (ABS) copolymer have been prepared and then filled with 2–8 wt % of silica nanoparticles. Membranes were fabricated by solution casting method using dimethylacetamide. The performance of prepared membranes were studied for methane and ethane at the feed pressure of 1.0, 1.5, 2.0, and 3.0 bar at 35°C. By increasing the percentage of ABS, permeability of methane and ethane increased. In addition, by adding the silica nanoparticles in the membrane, permeability of gas increased in all cases. The highest gas pair selectivity for C2H6/CH4 could be obtained from PVC/BS (20 wt %) which loaded with 8 wt % of silica nanoparticles. The results of this study suggest that high performance gas separation nanocomposite membranes can be attained by adopting a judicious combination of blending technique for polymeric membrane, optimized loading percentage, and feed operating conditions. 相似文献
42.
Salek Farhad Babaie Meisam Ghodsi Ali Hosseini Seyed Vahid Zare Ali 《Journal of Thermal Analysis and Calorimetry》2021,145(3):817-828
Journal of Thermal Analysis and Calorimetry - Number of hybrid vehicles has increased around the world significantly. Automotive industry is utilizing the hybridization of the powertrain system to... 相似文献
43.
44.
In this paper, we study maximal monotonicity preserving mappings on the Banach space X × X *. Indeed, for a maximal monotone set ${M \subset X\times X^*}$ and for a multifunction ${T: X \times X^* \multimap Y \times Y^*}$ , under some sufficient conditions on M and T we show that T(M) is maximal monotone. As two consequences of this result we get sum and composition rules for maximal monotone operators. 相似文献
45.
Meisam Amiri Vahid Esfahanian Mohammad Reza Hairi-Yazdi Mohsen Esfahanian Amir Mohammad Fazeli Ali Nabi 《Mathematical and Computer Modelling of Dynamical Systems: Methods, Tools and Applications in Engineering and Related Sciences》2013,19(2):191-207
With the stricter limitations on both fuel consumption and air pollution, the advantages of a hybrid electric vehicle are becoming more evident than ever. In the present study, an energy management system for a hybrid electric vehicle is developed. Because the plant under consideration is nonlinear, multi-domain, time-varying, has multiple uncertainties and, in addition, the designed control strategy must be able to obey the driver's commands and achieve the par-internship for a new generation of vehicle regulations, the fuzzy logic approach is chosen. A feed-forward hybrid vehicle simulation model is used to demonstrate the validity and the convenience of the current approach and its results have been compared with the other parallel hybrid electric vehicle control strategies. Simulation results show considerable improvement in the efficiency of the internal combustion engine and, consequently, fuel consumption and acceleration performances. 相似文献
46.
In this paper the generalized nonlinear Euler differential equation t2k(tu′)u″ + t(f(u)+ k(tu′))u′ + g(u) = 0 is considered. Here the functions f(u), g(u) and k(u) satisfy smoothness conditions which guarantee the uniqueness of solutions of initial value problems, however, no conditions of sub(super) linearity are assumed. We present some necessary and sufficient conditions and some tests for the equivalent planar system to have or fail to have property (X+), which is very important for the existence of periodic solutions and oscillation theory. 相似文献
47.
A new model for automatic normalization of multitemporal satellite images using Artificial Neural Network and mathematical methods 总被引:1,自引:0,他引:1
Relative Radiometric Normalization is often required in remote sensing image analyses particularly in the land cover change detection process. Normalization process minimizes the radiometric differences between two images caused by inequalities in the acquisition conditions rather than changes in surface reflectance. A wide range of RRN methods have been developed to adjust linear models. This paper proposes an automated Relative Radiometric Normalization (RRN) method to adjust a non-linear model based on an Artificial Neural Network (ANN) and unchanged pixels. The proposed method includes the following stages: (1) automatic detection of unchanged pixels based on a new idea that uses CVA (Change Vector Análysis) method, PCA (Principal Component Analysis) transformation and K-means clustering technique, (2) evaluation of different architectures of perceptron neural networks to find the best architecture for this specific task and (3) use of the aforementioned network for normalizing the subject image. The method has been implemented on two images taken by the TM sensor. Experimental results confirm the effectiveness of the presented technique in the automatic detection of unchanged pixels and minimizing imaging condition effects (i.e., atmosphere and other effective parameters). 相似文献
48.
Hamid Vahid 《Acta Analytica》2014,29(1):25-41
According to a recent view, known as the 'pragmatic encroachment' thesis, an agent’s non-truth-related factors are relevant to the epistemic status of her beliefs. In particular, in addition to truth-related factors, practical factors are said to be relevant to the question whether or not true belief amounts to knowledge. Despite the intuitive appeal of the thesis, however, it is puzzling how practical factors can impact the truth-related factors that ground the epistemic status of one's beliefs. In this paper, I will distinguish between a strong and a weak sense of the way in which practical factors are said to be thus relevant. Their differences are explicated in terms of the nature and the extent to which practical factors are said to impact the epistemic status of one's beliefs. I begin by considering a strong version of the thesis that suggests principles according to which the practical rationality of one's actions is a necessary condition on knowledge and justification. Having noted an inadequacy in the formulation of such principles, the arguments in their support are subsequently stated and criticized. Finally, I identify two modest versions of the thesis of pragmatic encroachment and argue that they, too, fail to explain how practical factors can bear on the epistemic status of one's beliefs. 相似文献
49.
Djafari Rouhani Behzad Mohebbi Vahid 《Journal of Optimization Theory and Applications》2020,186(1):134-147
Journal of Optimization Theory and Applications - By using our own approach, we study the strong convergence of an inexact proximal point algorithm with possible unbounded errors for a maximal... 相似文献
50.
We show theoretically that photonic crystal membranes cause large variations in the spontaneous emission rate of dipole emitters, not only inside but also in the near field above the membranes. Our three-dimensional finite-difference time-domain calculations reveal an inhibition of more than five times and an enhancement of more than ten times for the spontaneous emission rate of emitters with select dipole orientations and frequencies. Furthermore, we demonstrate theoretically the potential of a nanoscopic emitter attached to the end of a glass fiber tip as a local probe for mapping the large spatial variations of the photonic crystal local radiative density of states. This arrangement is promising for on-command modification of the coupling between an emitter and the photonic crystal in quantum optical experiments. 相似文献