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201.
Katayoun Marjani Maryam Asgari Akram Ashouri Gholam Hossein Mahdavinia Hossien Abbastabar Ahangar 《中国化学快报》2009,20(4):401-403
Under microwave irradiation,the corresponding hydroxycyciopentenones were prepared in high yields by the cross-aldol reactions of benzil with various ketones.When the reactions were performed in vailOUS solvents under classical heating for a long time,they produced the products in relatively low yields. 相似文献
202.
在BCK-代数中引入(∈,∈∨q)-模糊BCK-滤子的概念,讨论了它的某些性质.特别是,分别利用水平集和∈∨q-水平集给出了∈∨q-模糊BCK-滤子的若干特征. 相似文献
203.
Ernesto Acosta-Reyes Akram Aldroubi Ilya Krishtal 《Advances in Computational Mathematics》2009,31(1-3):5-34
A useful sampling-reconstruction model should be stable with respect to different kind of small perturbations, regardless whether they result from jitter, measurement errors, or simply from a small change in the model assumptions. In this paper we prove this result for a large class of sampling models. We define different classes of perturbations and present a way of quantifying the robustness of a model with respect to them. We also use the theory of localized frames to study the dual frame method for recovering the original signal from its samples. 相似文献
204.
In this paper q-Sobolev type spaces are defined on Rq by using the q-cosine Fourier transform and its inverse. In particular, embedding results for these spaces are established. Next we define the q-cosine potential and study some of its properties. 相似文献
205.
Recent research and new paradigms in mathematics, engineering, and science assume nonlinear signal models of the form ?=∪ i∈I V i consisting of a union of subspaces V i instead of a single subspace ?=V. These models have been used in sampling and reconstruction of signals with finite rate of innovation, the Generalized Principle Component Analysis and the subspace segmentation problem in computer vision, and problems related to sparsity, compressed sensing, and dictionary design. In this paper, we develop an algorithm that searches for the best nonlinear model of the form ?=∪ i=1 l V i ?? N that is optimally compatible with a set of observations ?={f 1,…,f m }?? N . When l=1 this becomes the classical least squares optimization. Thus, this problem is a nonlinear version of the least squares problem. We test our algorithm on synthetic data as well as images. 相似文献
206.
The article studies the application of the extended Fan sub-equation method to \((1+1)\)-dimensional nonlinear dispersive modified Benjamin-Bona-Mahony equation with fractional evolution. This equation describes the hydromagnetic waves in cold plasma, acoustic waves in inharmonic crystals and acoustic gravity waves in compressible fluids. The structure of the extended Fan sub-equation method on the basis of time-fractional derivative is presented. The main idea of the method is to take full advantage of the general elliptic equation involving five parameters. The fractional derivatives are taken as in the sense of Jumarie’s modified Riemann–Liouville derivative. The method is reliable and gives more general exact solutions than the existing methods. 相似文献
207.
Akram Nemri Fethi Soltani Abo-el-nour Abd-alla 《Complex Analysis and Operator Theory》2018,12(7):1549-1566
In this work, we introduce the Fock space \(F_\nu (\mathbb {C})\) associated to the Airy operator \(L_\nu \), and we establish Heisenberg-type uncertainty principle for this space. Next, we study the Toeplitz operators, the Hankel operators and the translation operators on this space. Furthermore, we give an application of the theory of extremal function and reproducing kernel of Hilbert space, to establish the extremal function associated to a bounded linear operator \(T{:}\,F_\nu (\mathbb {C})\rightarrow H\), where H be a Hilbert space. Finally, we come up with some results regarding the extremal functions, when T is the difference operator and the Dunkl-difference operator, respectively. 相似文献
208.
S. Nadeem Safia Akram 《Communications in Nonlinear Science & Numerical Simulation》2010,15(2):312-321
In the present note, we have discussed the effects of partial slip on the peristaltic flow of a MHD Newtonian fluid in an asymmetric channel. The governing equations of motion and energy are simplified using a long wave length approximation. A closed form solution of the momentum equation is obtained by Adomian decomposition method and an exact solution of the energy equation is presented in the presence of viscous dissipation term. The expression for pressure rise is calculated using numerical integration. The trapping phenomena is also discussed. The graphical results are presented to interpret various physical parameter of interest. It is found that the temperature field decreases with the increase in slip parameter L, and magnetic field M, while with the increase in Pr and Ec, the temperature field increases. 相似文献
209.
Alizadeh Abdolali Bagherinejad Akram Bayat Fahimeh Hosseini Seyed Yasub Zhu Long-Guan 《Molecular diversity》2019,23(3):651-656
Molecular Diversity - A new protocol has been developed for the diastereoselective synthesis of 1,3-cyclohexadienes using vinyl malononitriles, dibenzalacetones and NaH as reagents in THF. This... 相似文献
210.