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关键词

Fitzhugh-Nagumo；混沌；分数阶；磁通量 1

MIMO雷达；波形设计；谱分解；分式二次约束二次规划 1

Mittag-Leffler稳定性；分数阶；四元数神经网络；脉冲 1

仿真器 1

像融合；分数阶导数；直觉模糊集；多聚焦图像 1

共振能量转移 1

分数量子能级 1

分数阶微积分；分忆抗；分忆抗值；分数阶忆阻；分数阶记忆性突触 1

分数阶微积分；分数阶反向传播算法；分数阶最速下降法；均方误差；分数阶多尺度全局优化 1

分数阶离散系统；神经网络；DNA加密；彩色图像加密 1

分数阶系统；分岔图；分数PID控制器；陈氏多涡卷混沌系统；Genesio-Tesi混沌系统 1

分数阶系统；稳定性；中立时滞；鲁棒性；饱和性 1

化学量子能 1

可持续发展新型氢能源 1

可控性；分数阶阻尼系统；时变时滞；Gramian矩阵 1

各向异性 1

各向异性腐蚀 1

图像解析法 1

基于观测器的控制；奇异系统；分数阶；输入时滞；线性矩阵不等式 1

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Altered white matter microarchitecture in Parkinson’s disease: a voxel-based meta-analysis of diffusion tensor imaging studies

Xueling Suo, Du Lei, Wenbin Li, Lei Li, Jing Dai, Song Wang, Nannan Li, Lan Cheng, Rong Peng, Graham J Kemp, Qiyong Gong

《医学前沿（英文）》 2021年第15卷第1期页码 125-138 doi: 10.1007/s11684-019-0725-5

摘要： This study aimed to define the most consistent white matter microarchitecture pattern in Parkinson’s disease (PD) reflected by fractional anisotropy (FA), addressing clinical profiles and methodology-related heterogeneity. Web-based publication databases were searched to conduct a meta-analysis of whole-brain diffusion tensor imaging studies comparing PD with healthy controls (HC) using the anisotropic effect size–signed differential mapping. A total of 808 patients with PD and 760 HC coming from 27 databases were finally included. Subgroup analyses were conducted considering heterogeneity with respect to medication status, disease stage, analysis methods, and the number of diffusion directions in acquisition. Compared with HC, patients with PD had decreased FA in the left middle cerebellar peduncle, corpus callosum (CC), left inferior fronto-occipital fasciculus, and right inferior longitudinal fasciculus. Most of the main results remained unchanged in subgroup meta-analyses of medicated patients, early stage patients, voxel-based analysis, and acquisition with ＜30 diffusion directions. The subgroup meta-analysis of medication-free patients showed FA decrease in the right olfactory cortex. The cerebellum and CC, associated with typical motor impairment, showed the most consistent FA decreases in PD. Medication status, analysis approaches, and the number of diffusion directions have an important impact on the findings, needing careful evaluation in future meta-analyses.

关键词： Parkinson’s disease diffusion tensor imaging fractional anisotropy meta-analysis anisotropic effect size–signed differential mapping

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Fractional order extremum seeking approach for maximum power point tracking of photovoltaic panels

Ammar NEÇAIBIA,Samir LADACI,Abdelfatah CHAREF,Jean Jacques LOISEAU

《能源前沿（英文）》 2015年第9卷第1期页码 43-53 doi: 10.1007/s11708-014-0343-5

摘要： Due to the high interest in renewable energy and diversity of research regarding photovoltaic (PV) array, a great research effort is focusing nowadays on solar power generation and its performance improvement under various weather conditions. In this paper, an integrated framework was proposed, which achieved both maximum power point tracking (MPPT) and minimum ripple signals. The proposed control scheme was based on extremum-seeking (ES) combined with fractional order systems (FOS). This auto-tuning strategy was developed to maximize the PV panel output power through the regulation of the voltage input to the DC/DC converter in order to lead the PV system steady-state to a stable oscillation behavior around the maximum power point (MPP). It is shown that fractional order operators can improve the plant dynamics with respect to time response and disturbance rejection. The effectiveness of the proposed controller scheme is illustrated with simulations using measured solar radiation data.

关键词： extremum seeking (ES) fractional order control (FOC) fractional calculus photovoltaic (PV) panel maximum power point tracking (MPPT)

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Aspects of rock permeability

Lianyang ZHANG

《结构与土木工程前沿（英文）》 2013年第7卷第2期页码 102-116 doi: 10.1007/s11709-013-0201-2

摘要： Effective evaluation of rock permeability is required in different energy, engineering and environmental projects. Although much research has been conducted on rock permeability, it is still one of the most difficult tasks for practicing rock engineers to accurately determine rock permeability. Based on a comprehensive literature review, this paper outlines the key aspects of rock permeability by presenting the representative values of the permeability of different rocks, describing the empirical and semi-empirical correlations for estimating the permeability of rocks, and discussing the main factors affecting the permeability of rocks. The factors discussed include stress, depth, temperature, and discontinuity intensity and aperture. This paper also highlights the scale effect on rock permeability, interconnectivity of discontinuities, and anisotropy of rock permeability. This paper provides the fundamental and essential information required for effective evaluation of rock permeability.

关键词： rock permeability discontinuity stress temperature scale effect anisotropy

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基于队列智能方法的分数阶PIλDμ控制器设计 None

Pritesh SHAH, Sudhir AGASHE, Anand J. KULKARNI

《信息与电子工程前沿（英文）》 2018年第19卷第3期页码 437-445 doi: 10.1631/FITEE.1601495

摘要：近年来，队列智能方法逐步演变为一种基于人工智能的优化方法。本文首次采用队列智能方法对分数阶PID控制器的参数进行优化。验证了队列智能方法在分数阶PID控制器设计中的性能，并与其他方法如粒子群优化方法、遗传算法和改进的电磁算法等的性能进行比较。结果表明，与其它3种算法相比，队列智能方法在代价函数、计算时间和函数评估方面表现出更好性能。此外，队列智能方法对应的标准差表明，提出的方法在解决控制问题时具有鲁棒性。

关键词：队列智能；分数阶微积分；分数阶PID控制器；调节

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Robust switched fractional controller for performance improvement of single phase active power filter

H. AFGHOUL,F. KRIM,D. CHIKOUCHE,A. BEDDAR

《能源前沿（英文）》 2016年第10卷第2期页码 203-212 doi: 10.1007/s11708-015-0381-7

摘要： A novel controller is proposed to regulate the DC-link voltage of a single phase active power filter (SPAPF). The proposed switched fractional controller (SFC) consists of a conventional PI controller, a fractional order PI (FO-PI) controller and a decision maker that switches between them. Commonly, the conventional PI controller is used in regulation loops due to its advantages in steady-state but it is limited in transient state. On the other hand, the FO-PI controller overcomes these drawbacks but it causes dramatic degradation in control performances in steady-state because of the fractional calculus theory and the approximation method used to implement this kind of controller. Thus, the purpose of this paper is to switch to the PI controller in steady-state to obtain the best power quality and to switch to the FO-PI controller when external disturbances are detected to guarantee a fast transient state. To investigate the efficiency and accuracy of the SFC considering all robustness tests, an experimental setup has been established. The results of the SFC fulfill the requirements, confirm its high performances in steady and transient states and demonstrate its feasibility and effectiveness. The experiment results have satisfied the limit specified by the IEEE harmonic standard 519.

关键词： conventional PI controller fractional calculus (FC) total harmonic distortion (THD) Oustaloup continuous approximation (OCA) single phase active power filter (SPAPF)

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用于非线性混沌系统的基于分岔分数阶PID控制器设计方法 None

Karima RABAH, Samir LADACI, Mohamed LASHAB

《信息与电子工程前沿（英文）》 2018年第19卷第2期页码 180-191 doi: 10.1631/FITEE.1601543

摘要：提出一个新的鲁棒分数阶比例-积分-微分（FOPID）控制器，以其中一个不稳定的固定点来稳定一个扰动非线性混沌系统。基于使用分岔图的比例-积分-微分行为，分析非线性混沌系统的稳定性。提取控制器参数的初始集，其后续可通过二次准则优化。积分和微分分数阶也被二次准则识别。在两个非线性系统（陈氏多涡卷混沌系统和Genesio-Tesi混沌系统）中应用数值模拟，结果表明分数阶比例-积分-微分控制器在稳定非稳定固定点过程中，甚至在随机扰动情况下，能够提供最好的闭环系统性能。

关键词：分数阶系统；分岔图；分数PID控制器；陈氏多涡卷混沌系统；Genesio-Tesi混沌系统

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树盘干缩异向性引起应变的测算及分析

付宗营,赵景尧,蔡英春

《中国工程科学》 2014年第16卷第4期页码 25-29

摘要：

研究探讨了干燥过程中树盘受抑制干缩应变、自由干缩应变、弹性应变、黏弹性蠕变应变以及机械吸附蠕变的图像解析测算法；运用该方法测算了白桦树盘常规缓慢干燥（含水率分布均匀）过程中干缩异向性引起的弦向各应变，分析了干燥过程中不同含水率阶段的应力状态及应力与各应变的关系。结果表明：应变的图像解析测算法可满足精度要求；树盘干燥至fiber saturation point( FSP)以下，弦向首先受拉伸应力作用，随着干燥的进行，拉伸应力转变为压缩应力；应力方向与各应变对应关系不同，与黏弹性蠕变应变无明显对应关系，与机械吸附蠕变基本对应。

关键词：图像解析法树盘干缩异向性干燥应力弦向应变

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Unified description of sand behavior

Feng ZHANG, Bin YE, Guanlin YE

《结构与土木工程前沿（英文）》 2011年第5卷第2期页码 121-150 doi: 10.1007/s11709-011-0104-z

摘要： In this paper, the mechanical behavior of sand, was systematically described and modeled with a elastoplastic model proposed by Zhang et al. [ ]. Without losing the generality of the sand, a specific sand called as Toyoura sand, a typical clean sand found in Japan, has been discussed in detail. In the model, the results of conventional triaxial tests of the sand under different loading and drainage conditions were simulated with a fixed set of material parameters. The model only employs eight parameters among which five parameters are the same as those used in Cam-clay model. Once the parameters are determined with the conventional drained triaxial compression tests and undrained triaxial cyclic loading tests, then they are fixed to uniquely describe the overall mechanical behaviors of the Toyoura sand, without changing the values of the eight parameters irrespective of what kind of the loadings or the drainage conditions may be. The capability of the model is discussed in a theoretical way.

关键词： constitutive model sand stress-induced anisotropy density structure

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An improved method for image denoising based on fractional-order integration

Li Xu, Guo Huang, Qing-li Chen, Hong-yin Qin, Tao Men, Yi-fei Pu,huangguoxuli@163.com

《信息与电子工程前沿（英文）》 2020年第21卷第10期页码 1413-1534 doi: 10.1631/FITEE.1900727

摘要： Given that the existing methods damage the texture details of an image, a new method based on fractional integration is proposed. First, the formula is deduced by generalizing the , and then the approximate value of the operator is estimated by a numerical method. Finally, a mask operator of any order is constructed in eight pixel directions of the image. Simulation results show that the proposed method can protect the edge texture information of the image while removing the noise. Moreover, this method can obtain higher image feature values and better image vision after denoising than the existing denoising methods, because a mechanism is adopted during the iterative processing.

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一类分数阶多功能n阶蜂巢型RLC电路网络 Article

Ling ZHOU, Zhi-zhong TAN, Qing-hua ZHANG

《信息与电子工程前沿（英文）》 2017年第18卷第8期页码 1186-1196 doi: 10.1631/FITEE.1601560

摘要：研究了一类多功能n阶蜂巢型电阻网络模型，该问题一直未被解决。通过调节电路参数，该网络模型可以转化为含有多种功能的数个不同网络模型，例如一个规则的梯形网络、一个n阶三角形网络，等。我们导出了电阻网络的2个新的等效电阻公式，同时导出了LC网络的等效复阻抗公式，它们都属于分数阶范畴。首先，将一个复杂网络简化为一个简单的等效模型；其次，应用基尔霍夫定律，建立一个分式差分方程模型；再次，采用等效变换方法，给出非线性差分方程的通解。在实际应用中，获得了数个有趣的特殊结论。特别地，讨论分析了一个n阶LC复阻抗网络，发现了许多新的等效复阻抗特性。

关键词：蜂巢型网络；等效变换；分数阶差分方程；复阻抗特性

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Upper bound solution to seismic active earth pressure of submerged backfill subjected to partial drainage

《结构与土木工程前沿（英文）》 2021年第15卷第6期页码 1480-1493 doi: 10.1007/s11709-021-0776-y

摘要： In waterfront geotechnical engineering, seismic and drainage conditions must be considered in the design of retaining structures. This paper proposes a general analytical method to evaluate the seismic active earth pressure on a retaining wall with backfill subjected to partial steady seepage flow under seismic conditions. The method comprises the following steps: i) determination of the total head, ii) upper bound solution of seismic active earth thrust, and iii) deduction for the earth pressure distribution. The determination of total head h(x,z) relies on the Fourier series expansions, and the expressions of the seismic active earth thrust and pressure are derived by using the upper bound theorem. Parametric studies reveal that insufficient drainage and earthquakes are crucial factors that cause unfavorable earth pressure. The numerical results confirm the validity of the total head distribution. Comparisons indicate that the proposed method is consistent with other relevant existing methods in terms of predicting seismic active earth pressure. The method can be applied to the seismic design of waterfront retaining walls.

关键词： seismic active earth pressure partial seepage flow pore pressure anisotropy upper bound theorem

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Phosphorene: Current status, challenges and opportunities

Anandarup Goswami, Manoj B. Gawande

《化学科学与工程前沿（英文）》 2019年第13卷第2期页码 296-309 doi: 10.1007/s11705-018-1783-y

摘要： The field of 2-dimensional (2D) materials has witnessed a sharp growth since its inception and can majorly be attributed to the substantial technical and scientific developments, leading to significant improvements in their syntheses, characterization and applications. In the list of 2D materials, the relatively newer addition is phosphorene, which ideally consists of a single layer of black phosphorous. Keeping in mind the past, and ongoing research activities, this short account offers a brief overview of the present status and the associated challenges in the field of phosphorene-related research, with special emphasis on their syntheses, properties, applications and future opportunities.

关键词： phosphorene black phosphorous anisotropy single layer thermoelectric chemical vapor deposition catalysis battery supercapacitor

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Effect of anisotropic characteristics on the mechanical behavior of asphalt concrete overlay

Lingyun YOU, Zhanping YOU, Kezhen YAN

《结构与土木工程前沿（英文）》 2019年第13卷第1期页码 110-122 doi: 10.1007/s11709-018-0476-4

摘要： Asphalt concrete (AC) overlays placed over old asphalt pavement have become an alternative to repairing and reinforcing pavements. The strength contributed by the AC overlay is strongly influenced by the anisotropic properties of the pavement material. This study was conducted to analyze the influence of anisotropy, modulus gradient properties, and the condition of the AC overlay and old pavement contact plane on the mechanical behaviors of AC overlays, as well as to quantify the influence of the degree of anisotropy on the mechanical behaviors of AC overlay by a sensitivity analysis (SA). The mechanical behaviors of the AC overlay were numerically obtained using the three-dimensional finite element method with the aid of ABAQUS a commercial program. Variations in the AC overlay’s modulus as a function of temperature as well as the contact state between the AC overlay and AC layer were considered. The SA is based on standardized regression coefficients method. Comparing the mechanical behavior in terms of surface deflection, stress, and strain of the anisotropy model against those corresponding to the isotropic model under static loads show that the anisotropic properties had greater effects on the mechanical behavior of the AC overlay. In addition, the maximum shear stress in the AC overlay was the most significant output parameter affected by the degree of anisotropy. Therefore, future research concerning the reinforcement and repair of pavements should consider the anisotropic properties of the pavement materials.

关键词： asphalt concrete overlay anisotropy temperature gradients modulus gradients finite element simulation sensitivity analysis

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用改进的分数阶最速下降法训练分数阶全局最优反向传播机 Research Articles

蒲亦非1,王健2

《信息与电子工程前沿（英文）》 2020年第21卷第6期页码 809-962 doi: 10.1631/FITEE.1900593

摘要：本文介绍采用改进的分数阶最速下降法（FSDM）训练分数阶全局最优反向传播机。该反向传播机是一种分数阶反向传播神经网络（FBPNN）。分数阶反向传播神经网络是反向传播神经网络（BPNNs）大家族中一个先进的分数阶分支，它不同于绝大多数传统一阶最速下降法训练的经典一阶BPNNs。本文提出的FBPNN反向增量搜索在其均方误差近似分数阶偏导数的负方向进行。首先，从数学上描述用改进FSDM训练的FBPNN理论概念。然后，详细给出FBPNN分数阶全局最优收敛性的数学证明，分析神经网络结构构建以及分数阶多尺度全局寻优问题。最后，通过实验比较FBPNN和经典一阶BPNN的性能：包括函数逼近、分数阶多尺度全局寻优以及基于实际数据的全局搜索和误差拟合能力比对。相比经典一阶BPNN，FBPNN最主要优点是具有更高效的全局寻优能力，能够判定全局最优解。

关键词：分数阶微积分；分数阶反向传播算法；分数阶最速下降法；均方误差；分数阶多尺度全局优化

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整数阶与分数阶非连续外磁通量的神经元动力学 Regular Papers

Karthikeyan RAJAGOPAL, Fahimeh NAZARIMEHR, Anitha KARTHIKEYAN, Ahmed ALSAEDI, Tasawar HAYAT, Viet-Thanh PHAM

《信息与电子工程前沿（英文）》 2019年第20卷第4期页码 584-590 doi: 10.1631/FITEE.1800389

摘要：提出一种改进Fitzugh-Nagumo神经元（MFNN）模型。在此模型基础上，研究了基于整数阶（案例A）与分数阶（案例B）的MFNN系统。在电磁感应和辐射作用下，记忆和感应呈现多种分布，证明该分数阶磁通量适用于非均匀扩散。整数阶非连续磁通量MFNN系统具有混沌和非混沌吸引子。系统动力学分析显示倍周期的产生和消失标志着反单调性，神经元动力学研究未曾报道此现象。在分数阶非连续磁通量MFNN系统中，混沌吸引子和周期吸引子无反单调性。

关键词： Fitzhugh-Nagumo；混沌；分数阶；磁通量

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标题作者时间类型操作

Altered white matter microarchitecture in Parkinson’s disease: a voxel-based meta-analysis of diffusion tensor imaging studies

Xueling Suo, Du Lei, Wenbin Li, Lei Li, Jing Dai, Song Wang, Nannan Li, Lan Cheng, Rong Peng, Graham J Kemp, Qiyong Gong

期刊论文

Fractional order extremum seeking approach for maximum power point tracking of photovoltaic panels

Ammar NEÇAIBIA,Samir LADACI,Abdelfatah CHAREF,Jean Jacques LOISEAU

期刊论文

Aspects of rock permeability

Lianyang ZHANG

期刊论文