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排序方式: 共有191条查询结果,搜索用时 171 毫秒
11.
We consider the following system of fractional differential equations where is the Riemann‐Liouville fractional derivative of order α,f,g : [0,1] × [0, ∞ ) × [0, ∞ ) → [0, ∞ ). Sufficient conditions are provided for the existence of positive solutions to the considered problem. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
12.
Bayrakdar Alpaslan Mert Samet Kasımoğulları Rahmi Bangaru Sathya Manivannan Prasath 《Research on Chemical Intermediates》2022,48(5):2087-2109
Research on Chemical Intermediates - Trifluoromethyl group containing pyrazole-3-carboxamide derivative is synthesized and the structure of the molecule (E3N5PC) has been verified by using FT-IR,... 相似文献
13.
Phosphine‐ and Hydrogen‐Free: Highly Regioselective Ruthenium‐Catalyzed Hydroaminomethylation of Olefins
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Dr. Samet Gülak Lipeng Wu Dr. Qiang Liu Prof. Dr. Robert Franke Dr. Ralf Jackstell Prof. Dr. Matthias Beller 《Angewandte Chemie (International ed. in English)》2014,53(28):7320-7323
A highly regioselective ruthenium‐catalyzed hydroaminomethylation of olefins is reported. Using easily available trirutheniumdodecacarbonyl an efficient sequence consisting of a water‐gas shift reaction, hydroformylation of olefins, with subsequent imine or enamine formation and final reduction is realized. This novel procedure is highly practical (ligand‐free, one pot) and economic (low catalyst loading and inexpensive metal). Bulk industrial as well as functionalized olefins react with various amines to give the corresponding tertiary amines generally in high yields (up to 92 %), excellent regioselectivities (n/iso>99:1), and full chemoselectivity in favor of terminal olefins. 相似文献
14.
M. Samet G. Boiteux G. Seytre A. Kallel A. Serghei 《Colloid and polymer science》2014,292(8):1977-1988
The dielectric properties of composite materials consisting of a host matrix filled with spherical particles are investigated as a function of frequency by means of numerical calculations. Two different cases are analyzed: (a) composites with a conductive matrix and insulating fillers and (b) composites with an insulating matrix and conductive fillers. In both situations, dielectric dispersions due to interfacial polarization effects are observed in the dielectric spectra. In the present contribution, the characteristic frequencies of interfacial polarization effects are systematically analyzed in dependence on the volume fraction of the spherical fillers and on the conductivity values of the composite phases. The resulting scaling laws are discussed in detail. 相似文献
15.
Bessem Samet 《The European physical journal. Special topics》2017,226(16-18):3513-3524
We provide sufficient conditions for the non-existence of global solutions for a certain class of sequential fractional differential inequalities involving Riemann-Liouville left-sided fractional derivatives with different orders. To the best of our knowledge, the study of non-existence of solutions for fractional differential problems with sequential fractional derivatives has not been investigated until now. Our approach is based on the test function method. 相似文献
16.
Mohamed Masmoudi Mounir Samet Adel M. Alimi 《International Journal of Electronics》2013,100(6):675-682
The great flexibility of the Beta function and its universal approximation characteristics, make Beta basis function neural networks (BBFNNs) very useful. We present a hardware implementation of the Beta neuron. The proposed circuit was designed by using a standard bipolar technology. PSPICE simulations show the good concordance of the output of our circuit with the analytic Beta function. We also successfully integrated the electronic Beta neuron in the design of a BBFNN that approximates a nonlinear mapping. 相似文献
17.
Johnson Edgar M. Cavanagh Raymond C. Spooner Ronald L. Samet Michael G. 《Reliability, IEEE Transactions on》1973,(3):176-183
A normative 2-stage model for incorporating reliability measurements of data-reporting sources in a Bayesian inference system is presented. An experiment required human subjects to make intuitive inferences about two hypotheses on the basis of sample data which were reported with a given reliability. When compared with the optimal model, subjects exhibited systematic errors in estimating the diagnostic impact of less than perfectly reliable data. Their responses reflected the use of specific nonoptimal heuristic strategies to process the information. A utility function was added to the normative model to illustrate how a best choice might be made from among potential data-gathering experiments whose costs increase with their reliabilities. Recommendations for using computer aids to enhance efficiency in inference systems are made 相似文献
18.
We establish fixed point theorems for mixed monotone operators of Meir-Keeler type on ordered Banach spaces through projective metric. As applications, we use the fixed point theorems obtained in this paper to study the existence and uniqueness of positive solutions for different classes of nonlinear problems which include two-order two-point boundary value problems and fourth-order two-point boundary value problems for elastic beam equations. 相似文献
19.
In this article we investigate the impacts of interspacing and source polling policies on the cell‐loss rates in transmission
of variable bit rate video sources over Asynchronous Transfer Mode networks. We present a mathematical model that finds the
approximate optimal starting times of the video sources that minimize the congestion at the multiplexer. Combined with the
approximate optimal source starting times, we propose a source ordering and polling policy for reducing the cell‐loss rates.
The proposed policy is tested against alternative policies using simulation of pre‐recorded video data.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献