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On Solutions of Two Post-Quantum Fractional Generalized Sequential Navier Problems: An Application on the Elastic Beam 论两个后量子广义序列纳维问题的解:弹性梁的应用
IF 5.4 2区 数学 Q1 Mathematics Pub Date : 2024-04-17 DOI: 10.3390/fractalfract8040236
S. Etemad, Sotiris K. Ntouyas, I. Stamova, J. Tariboon
Fractional calculus provides some fractional operators for us to model different real-world phenomena mathematically. One of these important study fields is the mathematical model of the elastic beam changes. More precisely, in this paper, based on the behavior patterns of an elastic beam, we consider the generalized sequential boundary value problems of the Navier difference equations by using the post-quantum fractional derivatives of the Caputo-like type. We discuss on the existence theory for solutions of the mentioned (p;q)-difference Navier problems in two single-valued and set-valued versions. We use the main properties of the (p;q)-operators in this regard. Application of the fixed points of the ρ-θ-contractions along with the endpoints of the multi-valued functions play a fundamental role to prove the existence results. Finally in two examples, we validate our models and theoretical results by giving numerical models of the generalized sequential (p;q)-difference Navier problems.
分式微积分为我们提供了一些分式算子,用于对不同的现实世界现象进行数学建模。其中一个重要的研究领域就是弹性梁变化的数学模型。更确切地说,本文以弹性梁的行为模式为基础,利用类似卡普托类型的后量子分数导数,考虑纳维差分方程的广义序列边界值问题。我们讨论了上述 (p;q)-difference Navier 问题两种单值和集值版本的解的存在性理论。在这方面,我们使用了 (p;q) 运算符的主要特性。ρ-θ-contractions的定点应用以及多值函数的端点在证明存在性结果方面发挥了重要作用。最后,在两个例子中,我们通过给出广义顺序(p;q)差分纳维问题的数值模型,验证了我们的模型和理论结果。
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引用次数: 0
Stability and Bifurcation Control for a Generalized Delayed Fractional Food Chain Model 广义延迟分叉食物链模型的稳定性和分叉控制
IF 5.4 2区 数学 Q1 Mathematics Pub Date : 2024-04-16 DOI: 10.3390/fractalfract8040232
Qing Li, Hongxia Liu, Wencai Zhao, Xinzhu Meng
In this paper, a generalized fractional three-species food chain model with delay is investigated. First, the existence of a positive equilibrium is discussed, and the sufficient conditions for global asymptotic stability are given. Second, through selecting the delay as the bifurcation parameter, we obtain the sufficient condition for this non-control system to generate Hopf bifurcation. Then, a nonlinear delayed feedback controller is skillfully applied to govern the system’s Hopf bifurcation. The results indicate that adjusting the control intensity or the control target’s age can effectively govern the bifurcation dynamics behavior of this system. Last, through application examples and numerical simulations, we confirm the validity and feasibility of the theoretical results, and find that the control strategy is also applicable to eco-epidemiological systems.
本文研究了具有延迟的广义分数三物种食物链模型。首先,讨论了正平衡的存在性,并给出了全局渐近稳定性的充分条件。其次,通过选择延迟作为分岔参数,我们得到了该非控制系统产生霍普夫分岔的充分条件。然后,巧妙地应用非线性延迟反馈控制器来控制该系统的霍普夫分岔。结果表明,调整控制强度或控制目标的年龄可以有效地控制该系统的分岔动力学行为。最后,通过应用实例和数值模拟,我们证实了理论结果的正确性和可行性,并发现该控制策略同样适用于生态流行病学系统。
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引用次数: 0
Fractional Calculus and Hypergeometric Functions in Complex Analysis 复杂分析中的分式微积分和超几何函数
IF 5.4 2区 数学 Q1 Mathematics Pub Date : 2024-04-16 DOI: 10.3390/fractalfract8040233
G. Oros, G. Oros
Fractional calculus has had a powerful impact on recent research, with many applications in different branches of science and engineering [...]
分式微积分对近年来的研究产生了巨大的影响,在科学和工程学的不同分支中有许多应用 [...]
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引用次数: 0
A Low Power Analog Integrated Fractional Order Type-2 Fuzzy PID Controller 低功耗模拟集成分数阶 2 型模糊 PID 控制器
IF 5.4 2区 数学 Q1 Mathematics Pub Date : 2024-04-16 DOI: 10.3390/fractalfract8040234
Vassilis Alimisis, Nikolaos P. Eleftheriou, Evangelos Georgakilas, Christos Dimas, N. Uzunoglu, P. Sotiriadis
This paper introduces an analog integrated fractional order type-2 fuzzy PID control system. Current approaches frequently depend on energy-intensive embedded digital systems, consuming substantial energy levels ranging from a few μW to mW. To address this limitation we propose a fully analog design offering insights into the potential of analog circuits for powerefficient robust control in complex and uncertain environments. It consists of Gaussian function, min/max, Operational transcoductance amplifier circuits and Resistor-Capacitor networks for the implementation of the fractional-order components. Crafted for operation under a reduced voltage supply (0.6 V), the controller attains minimal power usage (861.8 nW), facilitating uninterrupted, extended-term functioning. Post-layout simulation results confirm the proper operation of the proposed design. The proposed system is designed and simulated using the Cadence IC Suite in a TSMC 90 nm CMOS process.
本文介绍了一种模拟集成分数阶 2 型模糊 PID 控制系统。目前的方法通常依赖于高能耗的嵌入式数字系统,能耗水平从几微瓦到几毫瓦不等。为解决这一局限性,我们提出了一种全模拟设计方案,让人们深入了解模拟电路在复杂和不确定环境下实现高能效稳健控制的潜力。它由高斯函数、最小/最大、运算跨导放大器电路和用于实现分数阶组件的电阻电容网络组成。该控制器可在电压较低的电源(0.6 V)下运行,功耗极低(861.8 nW),有利于不间断地长期运行。布局后仿真结果证实了拟议设计的正常运行。该系统采用 Cadence IC Suite 在台积电 90 纳米 CMOS 工艺中进行设计和仿真。
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引用次数: 0
Further Fractional Hadamard Integral Inequalities Utilizing Extended Convex Functions 利用扩展凸函数的进一步分式哈达玛积分不等式
IF 5.4 2区 数学 Q1 Mathematics Pub Date : 2024-04-16 DOI: 10.3390/fractalfract8040230
Areej A. Almoneef, M. Barakat, Abd-Allah Hyder
This work investigates novel fractional Hadamard integral inequalities by utilizing extended convex functions and generalized Riemann-Liouville operators. By carefully using extended integral formulations, we not only find novel inequalities but also improve the accuracy of error bounds related to fractional Hadamard integrals. Our study broadens the applicability of these inequalities and shows that they are useful for a variety of convexity cases. Our results contribute to the advancement of mathematical analysis and provide useful information for theoretical comprehension as well as practical applications across several scientific directions.
本研究利用扩展凸函数和广义黎曼-黎欧维尔算子研究了新的分数哈达玛积分不等式。通过精心使用扩展积分公式,我们不仅发现了新的不等式,还提高了与分数哈达玛积分相关的误差边界的准确性。我们的研究拓宽了这些不等式的适用范围,并表明它们适用于各种凸性情况。我们的成果有助于数学分析的发展,并为多个科学方向的理论理解和实际应用提供了有用的信息。
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引用次数: 0
Liquid Vortex Formation in a Swirling Container Considering Fractional Time Derivative of Caputo 考虑卡普托分数时间导数的漩涡容器中的液体漩涡形成
IF 5.4 2区 数学 Q1 Mathematics Pub Date : 2024-04-16 DOI: 10.3390/fractalfract8040231
M. Turkyilmazoglu, A. S. Alofi
This paper applies fractional calculus to a practical example in fluid mechanics, illustrating its impact beyond traditional integer order calculus. We focus on the classic problem of a rigid body rotating within a uniformly rotating container, which generates a liquid vortex from an undisturbed initial state. Our aim is to compare the time evolutions of the physical system in fractional and integer order models by examining the torque transmission from the rotating body to the surrounding liquid. This is achieved through closed-form, time-developing solutions expressed in terms of Mittag–Leffler and Bessel functions. Analysis reveals that the rotational velocity and, consequently, the vortex structure of the liquid are influenced by three distinct time zones that differ between integer and noninteger models. Anomalous diffusion, favoring noninteger fractions, dominates at early times but gradually gives way to the integer derivative model behavior as time progresses through a transitional regime. Our derived vortex formula clearly demonstrates how the liquid vortex is regulated in time for each considered fractional model.
本文将分数微积分应用于流体力学中的一个实际例子,说明分数微积分的影响超越了传统的整数阶微积分。我们将重点放在刚体在匀速转动容器内旋转的经典问题上,该问题会从未受损伤的初始状态产生液体漩涡。我们的目的是通过研究从旋转体到周围液体的扭矩传递,比较分数阶模型和整数阶模型中物理系统的时间演化。这是通过以 Mittag-Leffler 和贝塞尔函数表示的闭式时间发展解来实现的。分析表明,液体的旋转速度以及旋涡结构受到三个不同时间区域的影响,这三个区域在整数模型和非整数模型之间存在差异。反常的扩散有利于非整数分数,在早期占主导地位,但随着时间的推移,会逐渐让位于整数导数模型行为。我们推导出的漩涡公式清楚地表明了液体漩涡是如何随着时间的推移对每种所考虑的分数模型进行调节的。
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引用次数: 0
Field-Programmable Analog Array Implementation of Neuromorphic Silicon Neurons with Fractional Dynamics 现场可编程模拟阵列实现具有分数动态特性的神经形态硅神经元
IF 5.4 2区 数学 Q1 Mathematics Pub Date : 2024-04-15 DOI: 10.3390/fractalfract8040226
Andrés J. Serrano-Balbontín, I. Tejado, B. Vinagre
Silicon neurons are bioinspired circuits with the capability to reproduce the modulation through pulse-frequency observed in real neurons. They are of particular interest in closed-loop schemes to encode the control signal into pulses. This paper proposes the analog realization of neuromorphic silicon neurons with fractional dynamics. In particular, the fractional-order (FO) operator is introduced into classical neurons with the intention of reproducing the adaptation that has been observed experimentally in real neurons, which is the variation in the firing frequency even when considering a constant or periodic incoming stimulus. For validation purposes, simulations using a field-programmable analog array (FPAA) are performed to verify the behavior of the circuits.
硅神经元是一种生物启发电路,能够再现真实神经元中的脉冲频率调制。在将控制信号编码成脉冲的闭环方案中,硅神经元具有特别重要的意义。本文提出了具有分数动态的神经形态硅神经元的模拟实现方法。特别是在经典神经元中引入了分数阶(FO)算子,目的是再现在真实神经元中实验观察到的适应性,即即使考虑到恒定或周期性的输入刺激,发射频率也会发生变化。为了进行验证,使用现场可编程模拟阵列(FPAA)进行了模拟,以验证电路的行为。
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引用次数: 0
Fractal Characteristics and Microstructure of Coal with Impact of Starch-Polymerized Aluminum Sulfate Fracturing Fluids 淀粉聚合硫酸铝压裂液影响下煤炭的分形特征和微观结构
IF 5.4 2区 数学 Q1 Mathematics Pub Date : 2024-04-15 DOI: 10.3390/fractalfract8040228
Feng Cai, Qian Zhang, Lingling Yang
The degree of irregularity and complexity of the pore structure are comprehensively reflected in the fractal dimension. The porosity of coal was determined by its fractal dimension, where a larger dimension indicates a lower porosity. Fractal theory and the Frenkel–Halsey–Hill (FHH) model were applied to explore the variation rules of concentration on functional groups and pore structure in this study. Combined with infrared spectroscopy (FTIR) and low-temperature nitrogen adsorption, a starch-polymerized aluminum sulfate composite fracturing fluid was prepared, which plays an important role in methane adsorption and permeability of coal samples. The test results showed that, compared with the original coal, the pore volume and specific surface area of each group of coal samples were reduced, the average pore diameter was initially enlarged and then declined, and fractal dimension D1 dropped by 5.4% to 15.4%, while fractal dimension D2 gained 1.2% to 7.9%. Moreover, the nitrogen adsorption of each group of coal samples was obviously lower than the original coal, and the concentration of starch-polymerized aluminum sulfate solution existed at a critical optimal concentration for the modification of the coal samples, and the nitrogen adsorption reached a minimum value of 0.6814 cm3/g at a concentration of 10%. The novel composite solution prepared by the combination of starch and flocculant in this paper enhanced the permeability of the coal seam, which is of great significance in improving the efficiency of coalbed methane mining.
分形维度全面反映了孔隙结构的不规则程度和复杂性。煤的孔隙率由其分形维数决定,维数越大,孔隙率越低。本研究应用分形理论和 Frenkel-Halsey-Hill 模型探讨了浓度对官能团和孔隙结构的变化规律。结合红外光谱(FTIR)和低温氮气吸附,制备了淀粉聚合硫酸铝复合压裂液,该压裂液在煤样甲烷吸附和渗透中发挥了重要作用。试验结果表明,与原煤相比,各组煤样的孔隙体积和比表面积均减小,平均孔径先增大后减小,分形维数 D1 下降了 5.4% 至 15.4%,分形维数 D2 增加了 1.2% 至 7.9%。此外,各组煤样的氮气吸附量明显低于原煤,淀粉聚合硫酸铝溶液的浓度存在煤样改性的临界最佳浓度,浓度为10%时氮气吸附量达到最小值0.6814 cm3/g。本文通过淀粉与絮凝剂结合制备的新型复合溶液提高了煤层的透气性,对提高煤层气开采效率具有重要意义。
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引用次数: 0
Novel Hopf Bifurcation Exploration and Control Strategies in the Fractional-Order FitzHugh–Nagumo Neural Model Incorporating Delay 包含延迟的分数阶 FitzHugh-Nagumo 神经模型中的新型霍普夫分岔探索与控制策略
IF 5.4 2区 数学 Q1 Mathematics Pub Date : 2024-04-15 DOI: 10.3390/fractalfract8040229
Yunzhang Zhang, Changjin Xu
In this article, we propose a new fractional-order delay-coupled FitzHugh–Nagumo neural model. Taking advantage of delay as a bifurcation parameter, we explore the stability and bifurcation of the formulated fractional-order delay-coupled FitzHugh–Nagumo neural model. A delay-independent stability and bifurcation conditions for the fractional-order delay-coupled FitzHugh–Nagumo neural model is acquired. By designing a proper PDp controller, we can efficaciously control the stability domain and the time of emergence of the bifurcation phenomenon of the considered fractional delay-coupled FitzHugh–Nagumo neural model. By exploiting a reasonable hybrid controller, we can successfully adjust the stability domain and the bifurcation onset time of the involved fractional delay-coupled FitzHugh–Nagumo neural model. This study shows that when the delay crosses a critical value, a Hopf bifurcation will arise. When we adjust the control parameter, we can find other critical values to enlarge or narrow the stability domain of the fractional-order delay-coupled FitzHugh–Nagumo neural model. In order to check the correctness of the acquired outcomes of this article, we present some simulation outcomes via Matlab 7.0 software. The obtained theoretical fruits in this article have momentous theoretical significance in running and constructing networks.
本文提出了一种新的分数阶延迟耦合 FitzHugh-Nagumo 神经模型。利用延迟作为分岔参数的优势,我们探讨了所建立的分数阶延迟耦合 FitzHugh-Nagumo 神经模型的稳定性和分岔。我们获得了分数阶延迟耦合 FitzHugh-Nagumo 神经模型与延迟无关的稳定性和分岔条件。通过设计适当的 PDp 控制器,我们可以有效地控制分数阶延迟耦合 FitzHugh-Nagumo 神经模型的稳定域和分岔现象出现的时间。通过利用合理的混合控制器,我们可以成功地调整所涉及的分数延迟耦合 FitzHugh-Nagumo 神经模型的稳定域和分岔出现时间。研究表明,当延迟越过临界值时,就会出现霍普夫分岔。当我们调整控制参数时,可以找到其他临界值来扩大或缩小分数阶延迟耦合 FitzHugh-Nagumo 神经模型的稳定域。为了检验本文所获成果的正确性,我们通过 Matlab 7.0 软件给出了一些仿真结果。本文获得的理论成果对网络的运行和构建具有重要的理论意义。
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引用次数: 0
A Fractional-Order Archimedean Spiral Moth–Flame Optimization Strategy to Solve Optimal Power Flows 解决最优电力流的分数阶阿基米德螺旋蛾焰优化策略
IF 5.4 2区 数学 Q1 Mathematics Pub Date : 2024-04-13 DOI: 10.3390/fractalfract8040225
Abdul Wadood, Ejaz Ahmed, Sang Bong Rhee, Babar Sattar Khan
This research utilizes the innovative fractional-order Archimedean spiral moth–flame optimization (FO-AMFO) technique to address the issues of the optimal reactive power dispatch (ORPD) problem. The formulated fitness function aims to minimize power losses and determine the ideal flow of reactive power for the IEEE 30- and 57-bus test systems. The extensive functions of the fractional evolutionary computing strategy are utilized to address the minimization problem of ORPD. This involves determining the control variables, such as VAR compensators, bus voltages, and the tap setting of the transformers. The effective incorporation of reactive compensation devices into traditional power grids has greatly reduced power losses; however, it has resulted in an increase in the complexity of optimization problems. A comparison of the findings indicates that swarming fractional intelligence using FO-AMFO surpassed the state-of-the-art competitors in terms of minimizing power losses.
本研究利用创新的分数阶阿基米德螺旋蛾焰优化(FO-AMFO)技术来解决最佳无功功率调度(ORPD)问题。所制定的拟合函数旨在最大限度地减少功率损耗,并为 IEEE 30 和 57 总线测试系统确定理想的无功功率流。利用分数进化计算策略的广泛函数来解决 ORPD 的最小化问题。这包括确定控制变量,如 VAR 补偿器、母线电压和变压器的分接头设置。在传统电网中有效采用无功补偿装置大大降低了电能损耗,但同时也增加了优化问题的复杂性。对研究结果的比较表明,使用 FO-AMFO 的群分智能在最大限度减少电能损耗方面超越了最先进的竞争对手。
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引用次数: 0
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Fractal and Fractional
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