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1.
Riemann-Liouville分数阶微积分算子是一类带有一个函数的分数阶微积分算子的特殊情形,以Riemann-Liouville分数阶微积分算子的积分中值定理和微分中值定理为基础,我们得到了一类带有一个函数的分数阶微积分算子的积分中值定理和微分中值定理,并给出其在计算方面的一些应用。 相似文献
2.
Javier A. Gallegos Norelys Aguila-Camacho Manuel A. Duarte-Mermoud 《International Journal of Adaptive Control and Signal Processing》2020,34(11):1572-1589
In this article, we develop proportional, fractional-integral, and derivative () controllers for the regulation and tracking problems of nonlinear systems. The analytic results are obtained by extending the passivity-based approach to include fractional operators. Robustness under parametric uncertainty is dealt with by a combination with an adaptive scheme. It is also shown their robustness under additive noise and their robustness under uncertainty in the derivation order. The advantages in the controlled system performance and in the control energy consumption in comparison to classic PI and proportional integral derivative controllers are illustrated for the quadratic boost converter and a benchmark system in the literature. 相似文献
3.
Recent researches have reported that Android programs are vulnerable to unexpected exceptions. One reason is that the current design of Android platform solely depends on Java exception mechanism, which is unaware of the component-based structure of Android programs. This paper proposes a component-level exception mechanism for programmers to build robust Android programs with. With the mechanism, they can define an intra-component handler for each component to recover from exceptions, and they can propagate uncaught exceptions to caller component along the reverse of component activation flow. Theoretically, we have formalized an Android semantics with exceptions to prove the robustness property of the mechanism. In practice, we have implemented the mechanism with a domain-specific library that extends existing Android components. This lightweight approach does not demand the change of the Android platform. In our experiment with Android benchmark programs, the library is found to catch a number of runtime exceptions that would otherwise get the programs terminated abnormally. We also measure the overhead of using the library to show that it is very small. Our proposal is a new mechanism for defending Android programs from unexpected exceptions. 相似文献
4.
Rashid Jan Hassan Khan Poom Kumam Fairouz Tchier Rasool Shah Haifa Bin Jebreen 《计算机、材料和连续体(英文)》2021,68(3):3185-3201
It is eminent that partial differential equations are extensively meaningful in physics, mathematics and engineering. Natural phenomena are formulated with partial differential equations and are solved analytically or numerically to interrogate the system’s dynamical behavior. In the present research, mathematical modeling is extended and the modeling solutions Helmholtz equations are discussed in the fractional view of derivatives. First, the Helmholtz equations are presented in Caputo’s fractional derivative. Then Natural transformation, along with the decomposition method, is used to attain the series form solutions of the suggested problems. For justification of the proposed technique, it is applied to several numerical examples. The graphical representation of the solutions shows that the suggested technique is an accurate and effective technique with a high convergence rate than other methods. The less calculation and higher rate of convergence have confirmed the present technique’s reliability and applicability to solve partial differential equations and their systems in a fractional framework. 相似文献
5.
The optimization of a fixed-structure controller is in general computationally intractable, posing a challenge to control system engineers. This paper introduces a novel technique for designing such control techniques by formulating it as a nonlinear non-convex constrained problem. A novel PSO algorithm, namely the Augmented Lagrangian Particle Swarm Optimization with Fractional Order Velocity (ALPSOFV), is proposed for improving the convergence rate. The structure of the controller is selectable and, therefore, the Fractional Order Proportional Integral Derivative (FOPID) algorithm is chosen in the scope of the study. The results for three test examples show the good performance of the ALPSOFV. 相似文献
6.
J.I. Hidalgo-Reyes J.F. Gómez-Aguilar R.F. Escobar-Jimenez V.M. Alvarado-Martinez M.G. Lopez-Lopez 《International Journal of Circuit Theory and Applications》2019,47(8):1225-1253
In this paper, we estimate the parameter values of a fractional-order model of supercapacitors involving fractional derivatives of Liouville-Caputo, Caputo-Fabrizio, and Atangana-Baleanu and fractional conformable derivative in the Liouville-Caputo sense. We present the exact solution of the considered model using the properties of the Laplace transform operator together with the convolution theorem. They developed numerical simulations using each one of the fractional derivatives; the results were compared graphically with experimental data obtained from different supercapacitors using standard laboratory equipment. The nonlocal parameters involved in the equivalent electrical circuit for the supercapacitor model are recalculated for each fractional derivative using a particle swarm optimization algorithm for generating optimal solutions. 相似文献
7.
This article presents the construction and consumption of hyperjerk system having chaotic nature with the commensurate ordered fractional derivative on rapidly digitalized emerging technologies. The system analyzed analytically using Lipschitz condition and numerically with the help of predictor corrector approaches. Originality of constructed system is confirmed using log error plots which gives satisfactory small values on finite time scale. The dynamical performances of the complex system are termed in multiple phase planes by the mean of their significant nature. Stability and bifurcation analysis around the fractional derivative is also studies for the various parameter of system to check the visibility of chaotic solution. The system is also designed in analog circuit simulator with the aid of operational amplifier, anti-parallel semiconductor diodes for validation of the system. With the help of random number generators (RNGs), binary array generated from the hyperjerk system and plugged in to the NIST 800–22 test suite to measure the randomness. The array having high randomness is used as strong cypher key for the cryptographic execution straightforwardly in both direction encryption and decryption. 相似文献
8.
The recent trend of aging population, not to mention the unprecedented pandemic, draws great attention from the general public about health concerns. Since healthcare information technology is different from non-healthcare information technology, additional contexts should be properly incorporated into technology acceptance research to accurately identify influential factors affecting the acceptance of wearable healthcare technology. Thus, we selectively reconfigured factors from health, privacy, and socio-demographic contexts to formulate a health-aware acceptance model. Then, it was empirically analyzed using structural equation modeling. Based on the results, whereas privacy concerns were directly associated with intention to use wearable healthcare technology, health concerns were not. Moreover, age had a moderating effect on social influence and facilitating conditions. These findings suggest valuable insights that the adoption rate of healthcare technology is increased by 1) keeping personal information securely, 2) facilitating social interaction among users, and 3) offering intuitive user experience for elderly people. 相似文献
9.
A thin-walled beam is in pure bending subjected to couples M0. The open cross-section profile has two ribs, with cross-section A0 and it is shaped symmetrically towards the plane perpendicular to the bending plane. The ribs are located at the profile ends. The shape of the profile line is searched for. Criterion is the minimal value of the cross-section area A1 of the beam. The problem is described by means of variational calculus. Within the numerical calculations a Runge–Kutta method is used. The optimal shapes of beam profiles are shown graphically. 相似文献
10.
在分析JavaSIM卡的工作原理基础上,研究了GlobalPlatform系统的安全通信和卡上多应用程序管理的安全需求,设计实现了一种保证JavaSIM卡平台安全性的方案。本方案以密钥集的管理和应用为基础,通过划分不同密钥集的认证管理权限和提供安全信道,实现了不同卡外实体对卡内容的安全管理。对实现方案测试的结果符合相关规范的规定。 相似文献