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期刊论文 14

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2023 1

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2019 2

2018 2

2016 1

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2014 2

2009 1

2006 1

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关键词

细水雾 2

π-演算 1

一氧化碳 1

主体 1

二氧化碳 1

交换机 1

到达曲线 1

延迟 1

心智状态 1

服务曲线 1

氧气 1

烟颗粒 1

网络微积分 1

表面密度 1

认知过程 1

超高速撞击；变分贝叶斯；稀疏表示；损伤评估 1

采样平均直径 1

队列智能；分数阶微积分；分数阶PID控制器；调节 1

霍曼转移；非线性规划；约束优化；变分法 1

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Stability analysis of slopes with planar failure using variational calculus and numerical methods

Norly BELANDRIA, Roberto ÚCAR, Francisco M. LEÓN, Ferri HASSANI

《结构与土木工程前沿（英文）》 2020年第14卷第5期页码 1262-1273 doi: 10.1007/s11709-020-0657-9

摘要： This study investigates the technique of variational calculus applied to estimate the slope stability considering the mechanism of planar failure. The critical plane failure surface should be determined because it theoretically indicates the most unfavorable plane to be considered when stabilizing a slope to rectify the instability generated by several statistically possible planes. This generates integrals that can be solved by numerical methods, such as the Newton Cotes and the finite differences methods. Additionally, a system of nonlinear equations is obtained and solved. The surface of the critical planar failure is determined by applying the condition of transversality in mobile boundaries, for which various examples are provided. The number of slices is varied in one of the examples, while the surface of the critical planar failure is determined in the others. Results are compared using analytical methods through axis rotations. All the results obtained by considering normal stress, safety factors, and critical planar failure are nearly the same; however, in this research, a study is carried out for “ ” number of slices using programming methods. Sub-routines are important because they can be applied in slopes with different geometry, surcharge, interstitial pressure, and pseudo-static load.

关键词： slopes stability planar failure variational calculus numerical methods

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Variational mode decomposition based modal parameter identification in civil engineering

Mingjie ZHANG, Fuyou XU

《结构与土木工程前沿（英文）》 2019年第13卷第5期页码 1082-1094 doi: 10.1007/s11709-019-0537-3

摘要： An out-put only modal parameter identification method based on variational mode decomposition (VMD) is developed for civil structure identifications. The recently developed VMD technique is utilized to decompose the free decay response (FDR) of a structure into to modal responses. A novel procedure is developed to calculate the instantaneous modal frequencies and instantaneous modal damping ratios. The proposed identification method can straightforwardly extract the mode shape vectors using the modal responses extracted from the FDRs at all available sensors on the structure. A series of numerical and experimental case studies are conducted to demonstrate the efficiency and highlight the superiority of the proposed method in modal parameter identification using both free vibration and ambient vibration data. The results of the present method are compared with those of the empirical mode decomposition-based method, and the superiorities of the present method are verified. The proposed method is proved to be efficient and accurate in modal parameter identification for both linear and nonlinear civil structures, including structures with closely spaced modes, sudden modal parameter variation, and amplitude-dependent modal parameters, etc.

关键词： modal parameter identification variational mode decomposition civil structure nonlinear system closely spaced modes

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交换式以太网NC建模与实时性能分析

王晓欣,刘鲁源,刘昆,马津艳

《中国工程科学》 2006年第8卷第6期页码 55-59

摘要：

交换式以太网的实时性能分析是工业以太网研究领域的一个热点课题，目前还没有一个有效的数学模型来对其进行描述。通过对典型交换机结构的分析，应用网络微积分理论建立了交换机的服务曲线模型，该模型将交换机中的数据流分为实时数据和非实时数据，并得到了最大延迟值和最大缓存需求值等，最大延迟为交换机的实时应用提供了理论边界值，最大缓存需求值为在实时工业环境中的交换机构建提供了理论参考。

关键词：网络微积分交换机到达曲线服务曲线延迟

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基于变分贝叶斯多稀疏成分提取的空间碎片超高速撞击损伤重构方法研究 Research Article

黄雪刚,石安华,罗庆,罗锦阳

《信息与电子工程前沿（英文）》 2022年第23卷第4期页码 530-541 doi: 10.1631/FITEE.2000575

摘要：为提高在轨航天器抵御空间碎片撞击的生存能力，提出一种撞击损伤评估方法。首先，建立一个针对红外热图像序列数据的多区域损伤挖掘模型，用于描述处于不同空间层的撞击损伤。采用变分贝叶斯推理来求解模型参数，从而有效地从红外热图像数据中识别不同类型撞击损伤。然后，提出一种图像处理框架，包括具有能量函数的图像分割算法和具有稀疏表示的图像融合方法，以消除变异贝叶斯误差并比较不同类型损伤的位置。在试验部分，将上述方法用于评估二次碎片云对Whipple防护结构的复杂撞击损伤。实验结果证明本文提出的方法可以对空间碎片超高速撞击造成的不同类型复杂损伤进行有效识别与评估。

关键词：超高速撞击；变分贝叶斯；稀疏表示；损伤评估

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细水雾作用下烟颗粒形貌及尺寸变化规律研究

房玉东

《中国工程科学》 2014年第16卷第2期页码 93-100

摘要：

利用Sirion200 型场发射扫描电子显微镜拍摄细水雾作用前后柴油和聚氯乙烯（PVC）材料烟颗粒的形貌和内部结构图像。定义了烟颗粒的采样平均直径（dA）和表面密度（ρS），利用统计分析的方法计算了细水雾作用前后烟颗粒的dA和ρS，研究了采样点空间位置、细水雾工作压力、雾滴粒径和雾滴速度等因素对dA和ρS的影响规律，揭示了细水雾冲刷火灾烟颗粒的主导机理，为细水雾技术用于计算机房等电气环境的火灾烟气抑制提供了科学的参考依据。

关键词：细水雾烟颗粒表面密度采样平均直径

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Agent的PASS-BDI模型

樊玮,陈增强,袁著祉

《中国工程科学》 2004年第6卷第6期页码 43-49

摘要：

Agent的BDI模型主要基于Bratman提出的理性主体理论，未能充分体现Agent主动性的认知过程，使Agent的问题求解和心智状态之间的关系未得到充分表达，且难于编程实现。将Das等人提出的计划—注意—同时性加工—继时性加工认知过程模型引入Agent的理论研究中，建立了Agent的PASS-BDI模型，利用多价π-演算从心智状态，认知过程，整体行为等几个方面刻画了该模型的静态和动态特征，并将研究结果应用于多Agent组织中Agent行为特征的刻画。PASS-BDI模型加强了对Agent主动性认知过程的刻画，且易于编程实现。

关键词：主体 π-演算认知过程心智状态

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A novel hybrid model for water quality prediction based on VMD and IGOA optimized for LSTM

《环境科学与工程前沿（英文）》 2023年第17卷第7期 doi: 10.1007/s11783-023-1688-y

摘要：

● A novel VMD-IGOA-LSTM model has proposed for the prediction of water quality.

关键词： Water quality prediction Grasshopper optimization algorithm Variational mode decomposition Long short-term memory neural network

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A FEniCS implementation of the phase field method for quasi-static brittle fracture

HIRSHIKESH, Sundararajan NATARAJAN, Ratna Kumar ANNABATTULA

《结构与土木工程前沿（英文）》 2019年第13卷第2期页码 380-396 doi: 10.1007/s11709-018-0471-9

摘要： In the recent years, the phase field method for simulating fracture problems has received considerable attention. This is due to the salient features of the method: 1) it can be incorporated into any conventional finite element software; 2) has a scalar damage variable is used to represent the discontinuous surface implicitly and 3) the crack initiation and subsequent propagation and branching are treated with less complexity. Within this framework, the linear momentum equations are coupled with the diffusion type equation, which describes the evolution of the damage variable. The coupled nonlinear system of partial differential equations are solved in a ‘staggered’ approach. The present work discusses the implementation of the phase field method for brittle fracture within the open-source finite element software, FEniCS. The FEniCS provides a framework for the automated solutions of the partial differential equations. The details of the implementation which forms the core of the analysis are presented. The implementation is validated by solving a few benchmark problems and comparing the results with the open literature.

关键词： phase field method FEniCS brittle fracture crack propagation variational theory of fracture

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约束优化下的霍曼转移 None

Li XIE, Yi-qun ZHANG, Jun-yan XU

《信息与电子工程前沿（英文）》 2018年第19卷第11期页码 1444-1458 doi: 10.1631/FITEE.1800295

摘要：在Jean-Pierre MAREC几何方法启发下，将两共面圆轨道之间的霍曼转移问题定义为一个不等式约束下的静态非线性规划问题。利用Kuhn-Tucker定理和最小值点存在的一个二阶充分条件，证明霍曼转移的全局最小性。该约束优化问题存在两组可行解，其中对应于霍曼转移的一个解是全局极小值点，另一个解是局部极小值点。随后将霍曼转移问题考虑为有约束的动态优化问题，并用变分法转化为边值问题求解。在静态和动态优化数值算例中验证了静态优化解析给出的两组可行解。由静态和动态约束优化，我们重新发现霍曼转移问题的解，并用非线性规划解析证明了其全局最小性。

关键词：霍曼转移；非线性规划；约束优化；变分法

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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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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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细水雾作用下烟气组分浓度变化规律的模拟研究

房玉东

《中国工程科学》 2014年第16卷第8期页码 99-105

摘要：

在ISO 9705 标准房间通过模拟实验研究了细水雾与火灾烟气的相互作用，揭示了细水雾作用下烟气中氧气、一氧化碳和二氧化碳浓度的变化规律，建立了氧气、一氧化碳和二氧化碳浓度与细水雾工作压力及风机速率的数学模型。实验发现当风机速率达到1.5 kg/s 时烟气组分浓度变化规律发生突变，对这一现象进行了深入分析和解释。本文为细水雾技术用于火灾烟气抑制提供了必要的理论基础和科学的参考依据。

关键词：细水雾氧气一氧化碳二氧化碳

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

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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Mechanics analysis of thin-walled box continuous girder with variable cross-sections in considering effect of large deflection and shear lag

Yuji CHEN, Qizhi LUO,

《结构与土木工程前沿（英文）》 2009年第3卷第4期页码 352-356 doi: 10.1007/s11709-009-0057-7

摘要： In order to study the mechanics behavior of a thin-walled box continuous girder with variable cross-sections, using potential variation theories, considering the effect of shear lag of flange’s stress and the nonlinear geometry of vertical displacement, and evolving five generalized displacements with the spline function, the large deflection problem of the thin-walled box continuous girder with variable cross-section was transformed to a nonlinear algebraic equation, which was solved using the Newton-Raphon iterative method. The results of the calculation show that different shear lag warp functions to the cantilever, top and bottom plate should be taken to analyze the mechanics behavior of the thin-walled box continuous girder reliably. The thin-walled box continuous girder with variable cross-sections has more reasonable stress state and is more adaptable for the longitudinal change of internal forces than that with equal cross-sections. The effect of large deflection on the stress and displacement of the thin-walled box continuous girder with variable cross-sections depends on the values of the load.

关键词： thin-walled box girder with variable cross-sections potential variational theory shear lag large deflection problem