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121.
In this work, we briefly discuss a novel class of modified gravity like f(T, TG) gravity. In this background, we assume the new agegraphic version of pilgrim dark energy and reconstruct f(T, TG) models for two specific values of s. We also discuss the equation of state parameter, squared speed of sound and wDE-w'DE plane for these reconstructed f(T, TG) models. The equation of state parameter provides phantom-like behavior of the universe. The wDE-w'DE plane also corresponds to CDM limit, thawing and freezing regions for both models. 相似文献
122.
In this article, we proposed a new scheme to encrypt highly autocorrelated image pixel data. In existing literature, single substitution was used to break autocorrelation in images. To get better results, instead of single substitution box, some researchers are minimizing the autocorrelation via utilizing multiple substitution boxes. However, we found that multiple substitution boxes cannot solve the problem of autocorrelation independently. Therefore, we added chaotic confusion and diffusion to the existing substitution scheme in order to remove the correlation completely. Initially, we break the autocorrelation of data by permuting the pixels via TD-ERCS chaotic map. Bitwise XOR is carried out for diffusion using logistic map followed by the existing substitution scheme. Experimental analysis shows that the proposed scheme has greater resistance to brute force attack and statistical attack. Further analyses such as statistical analysis, peak signal-to-noise ratio, contrast analysis, key space analysis, entropy analysis, correlation analysis, key sensitivity analysis, and encryption quality analysis proved the high robustness of the proposed scheme. 相似文献
123.
We investigate the dynamics of a charged particle being kicked off from its circular orbit around a regular black hole by an incoming massive particle in the presence of magnetic field. The resulting escape velocity, escape energy and the effective potential are analyzed. It is shown that the presence of even a very weak magnetic field helps the charged particles in escaping the gravitational field of the black hole. Moreover the effective force acting on the particle visibly reduces with distance. Thus particle near the black hole will experience higher effective force as compared to when it is far away. 相似文献
124.
Jawad?AbracheEmail author Teodor?Gabriel?Crainic Michel?Gendreau 《4OR: A Quarterly Journal of Operations Research》2004,2(1):1-33
Combinatorial auctions are an important class of market mechanisms in which participants are allowed to bid on bundles of multiple heterogeneous items. In this paper, we discuss several complex issues that are encountered in the design of combinatorial auctions. These issues are related to the formulation of the winner determination problem, the expression of combined bids, the design of progressive combinatorial auctions that require less information revelation, and the need for decision support tools to help participants make profitable bidding decisions. For each issue, we survey the existing literature and propose avenues for further research.Received: April 2003, Revised: July 2003, AMS classification:
91B26, 90BXX, 90C27All correspondence to:Jawad Abrache 相似文献
125.
We characterize Banach lattices on which the class of order weakly compact operators coincides with that of b-weakly compact operators. 相似文献
126.
127.
We establish necessary and sufficient conditions under which b-weakly compact operators between Banach lattices have b-weakly
compact adjoints or operators with b-weakly compact adjoints are themselves b-weakly compact. Also, we give some consequences.
相似文献
128.
129.
Anjan Biswas Anwar Ja'afar Muhammad Jawad Wayne N. Manrakhan Amarendra K. Sarma Kaisar R. Khan 《Optics & Laser Technology》2012,44(7):2265-2269
The Schrödinger–Hirota equation governs the propagation of optical solitons in a dispersive optical fiber. In this paper, this equation will be solved by the ansatz method for bright and dark 1-soliton solution. The power law nonlinearity will be assumed. By using the tanh method, some additional solutions will be derived. Finally, the numerical simulations will be given. 相似文献