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1.
Annals of Operations Research - In recent years, operations research in agriculture has improved the harvested yield, reduced the cost and time required for field operations, and maintained...  相似文献   
2.
In this paper, the Vieta–Fibonacci wavelets as a new family of orthonormal wavelets are generated. An operational matrix concerning fractional integration of these wavelets is extracted. A numerical scheme is established based on these wavelets and their fractional integral matrix together with the collocation technique to solve fractional pantograph equations. The presented method reduces solving the problem under study into solving a system of algebraic equations. Several examples are provided to show the accuracy of the method.  相似文献   
3.
We consider the solvability of fractional differential equations involving the Riesz fractional derivative. Our approach basically relies on the reduction of the problem considered to the equivalent nonlinear mixed Volterra and Cauchy-type singular integral equation and on the theory of fractional calculus. By establishing a compactness property of the Riemann–Liouville fractional integral operator on Lebesgue spaces and using the well-known Krasnoselskii's fixed point theorem, an existence of at least one solution is gleaned. An example is finally included to show the applicability of the theory.  相似文献   
4.
In this work, the isolation step in the linear ion trap was performed using different “q values” conditions at a low collision-induced dissociation (CID) energy leading to the parent ion resolution improvements, reasonably due to better ion energy distribution. According to the results, we obtained a greater resolution and mass accuracy operating in both traditional electrospray and low voltage ionization near the q value = 0.778 and with a CID energy of 10%. This effect was evaluated with low-molecular-mass compounds (skatole and arginine). The proposed optimization yielded a superior instrument performance without adding technological complexity to mass spectrometry analyses.  相似文献   
5.
Colloid Journal - Preparation of complex nano- and micron-sized non-spherical particulate geometries still remains a challenge. One potential approach is the utilization of natural templates with...  相似文献   
6.
Nonlinear Dynamics - In this paper, we analytically and numerically investigate chaos in attitude dynamics of a flexible satellite composed of a rigid body and two identical rigid panels attached...  相似文献   
7.
The Paul Erd?s and András Gyárfás conjecture states that every graph of minimum degree at least 3 contains a simple cycle whose length is a power of two. In this paper, we prove that the conjecture holds for Cayley graphs on generalized quaternion groups, dihedral groups, semidihedral groups and groups of order \(p^3\).  相似文献   
8.
We introduce the notion of predicted decrease approximation (PDA) for constrained convex optimization, a flexible framework which includes as special cases known algorithms such as generalized conditional gradient, proximal gradient, greedy coordinate descent for separable constraints and working set methods for linear equality constraints with bounds. The new scheme allows the development of a unified convergence analysis for these methods. We further consider a partially strongly convex nonsmooth model and show that dual application of PDA-based methods yields new sublinear convergence rate estimates in terms of both primal and dual objectives. As an example of an application, we provide an explicit working set selection rule for SMO-type methods for training the support vector machine with an improved primal convergence analysis.  相似文献   
9.
Journal of Thermal Analysis and Calorimetry - The nanofluid is a mixture of base fluid and solid nanoparticles in nanosize. The heat transfer generated by the nanofluid is more than the base fluid...  相似文献   
10.

In the current study, we reported a novel label-free and facile colorimetric approach for the sequential detection of copper ion (Cu2+), l-arginine (Arg), and l-cysteine (Cys) in the H2O (10.0 mmol L−1 HEPES buffer solution, pH 7.0) using Reactive Blue 4 (RB4). First, the presence of Cu2+ led to a naked-eye color and spectral changes according to the binding site-signaling subunit approach. Then, the RB4-Cu2+ complex was successfully applied for Cys and Arg through different recognition pathways. The optical signals for Arg were observed due to its association involving the amino group, as well as the participation of the carboxylate group in a bidentate form to the complex, while selective behavior for Cys was explained by a metal displacement mechanism. The limits of detection for Cu2+, Arg, and Cys were calculated to be 1.96, 1.06, and 1.33 μmol L−1, respectively. It could also be employed for the determination of three analytes in environmental, biological, and pharmaceutical samples. Importantly, the test strips based on RB4-Cu2+ complex could be used as a solid-state sensor for the detection of Cys and Arg. In addition, NAND and IMPLICATION molecular logic gates were obtained by using chemical inputs and UV-Vis absorbance signal as the output.

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