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动水头作用下花岗岩风化土的内部侵蚀机理

水土保持通报 2024年第2期44卷 80-90页

作者：王浩严耿明李传东豆红强福州大学紫金地质与矿业学院福建福州350108 福州大学土木工程学院福建福州350108

[目的]揭示动水头作用下花岗岩风化土侵蚀演化的动态过程,研究动态水力条件对土体内部侵蚀发展的影响,探明颗粒迁移规律与内部侵蚀机理,为深入研究花岗岩边坡的破坏模式与促滑机理提供理论依据。[方法]设计竖向土柱渗流装置,开展上升水... 详细信息

[目的]揭示动水头作用下花岗岩风化土侵蚀演化的动态过程,研究动态水力条件对土体内部侵蚀发展的影响,探明颗粒迁移规律与内部侵蚀机理,为深入研究花岗岩边坡的破坏模式与促滑机理提供理论依据。[方法]设计竖向土柱渗流装置,开展上升水头与正弦水头条件下花岗岩风化土柱的渗流试验,基于渗流土柱顶面与侧面的试验现象,从渗流速度变化、颗粒流失量变化和渗流前后颗粒级配、质量变化等方面,分析动水头作用下花岗岩风化土内部侵蚀的发育特征。[结果]①花岗岩风化土粒径差异较大,在骨架间存在微小孔隙,渗流冲刷作用使得土颗粒通过土体骨架间的孔隙运移流失。在内部侵蚀过程中,细颗粒流失量相对较多,粗颗粒流失量较少。②土体内部侵蚀作用是渐进发展的过程,在土体薄弱区域的结构最先产生变形与破坏。试验中渗流泉眼由土柱边界开始发展到土柱中部区域,渗流通道沿着渗流方向自下而上发育,水力条件短时间内发生显著变化会造成渗流通道快速贯通。③土体内部侵蚀作用将随渗流时间推进而趋于稳定,但正弦水头将“激活”土颗粒运动,加剧土体的内部侵蚀作用。加大水头变化幅度或减小水头变化周期,能够加剧土体内部侵蚀作用,导致水流运移速度加快以及颗粒迁移流失量增多。[结论]水力条件变化对土体内部侵蚀作用存在显著影响,正弦水头更能加剧颗粒迁移流失。

关键词：模型试验花岗岩风化土动水头内部侵蚀

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海上风电配置储能关键问题分析及建议

油气与新能源 2024年第1期36卷 28-33页

作者：郭姝君王建明李传栋中国海油集团能源经济研究院北京100013 国网福建省电力有限公司电力科学研究院福建福州350007

海上风电配置储能是解决大规模海上风电并网后给电力系统带来调峰、调频乃至稳定问题的重要手段之一,但中国多地出台的新能源配置储能政策缺乏对配置储能的必要性、配置比例的科学性及配套机制经济性的深入分析。针对海上风电配置储能... 详细信息

海上风电配置储能是解决大规模海上风电并网后给电力系统带来调峰、调频乃至稳定问题的重要手段之一,但中国多地出台的新能源配置储能政策缺乏对配置储能的必要性、配置比例的科学性及配套机制经济性的深入分析。针对海上风电配置储能关键问题,总结分析了储能应用现状、国内外行业政策及特点、新能源配置储能的方式以及海上风电应用场景,进而提出海上风电配置储能的必要性分析原则和方法,最后从政策、技术、市场、标准等方面提出建议。

关键词：海上风电储能电源侧储能电网侧储能关键问题机制优化

Consensus of multi-agent systems with dynamic join characteristics under impulsive control

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Frontiers of Information Technology & Electronic Engineering 2021年第1期22卷 120-133页

作者： Xiang HU Zufan ZHANG chuandong li School of Communication and Information Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China Chongqing Key Laboratory of Nonlinear Circuits and Intelligent Information Processing College of Electronic and Information EngineeringSouthwest UniversityChongqing 400715China

We study how to achieve the state consensus of a whole multi-agent system after adding some new agent groups dynamically in the original multi-agent *** analyze the feasibility of dynamically adding agent groups under differen t forms of net work topologies that are currently common,and obtain four feasible schemes in theory,including one scheme that is the best in actual industrial ***,we carry out dynamic modeling of multi-agent systems for the best *** control theory and Lyapunov stability theory are used to analyze the conditions so that the whole multi-agent system with dynamic join characteristics can achieve state ***,we provide a numerical example to verify the practicality and validity of the theory.

关键词： Multi-agent system Network topology Impulsive input Dynamic join charac teristics State consensus

Globally Exponential Stability of Memristive Neural Networks With Time-varying Delays and Synchronous Switching

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自动化学报 2017年第8期43卷 1465-1469页

作者： Yinlu Jiang chuandong li College of Electronic and Information Engineering Southwest UniversityChongqing 400715China

In this paper, we formulate and investigate a memristive neural networks with time-varying delays and synchronous switching. Conditions are derived which ensure the existence of an equilibrium point and uniform stability for state trajectories of the memristive neural network. The analysis in the paper employs results from the theory of Lyapunov function. Moreover, the proposed stability conditions are straightforward and convenient which can reflect the impact of time-varying delays on the stability. The simulation results demonstrate the effectiveness of the theoretical results.

关键词：全局指数稳定性神经网络同步切换变时滞记忆李雅普诺夫状态轨迹函数理论

Exponential stability of memristor-based synchronous switching neural networks with time delays

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International Journal of Biomathematics 2016年第1期9卷 301-318页

作者： Yinlu Jiang chuandong li College of Electronic and Information EngineeringSouthwest University Chongqing 400715 P. R. China

In this paper, we study the existence, uniqueness and stability of memristor-based synchronous switching neural networks with time delays. Several criteria of exponential stability are given by introducing multiple Lyapunov functions. In comparison with the existing publications on simplice memristive neural networks or switching neural networks, we consider a system with a series of switchings, these switchings are assumed to be synchronous with memristive switching mechanism. Moreover, the proposed stability conditions are straightforward and convenient and can reflect the impact of time delay on the stability. Two examples are also presented to illustrate the effectiveness of the theoretical results.

关键词：时滞神经网络指数稳定性同步切换稳定性条件切换机制时间延迟 SYN 出版物

Thienothiophene-centered ladder-type π-systems that feature distinct quinoidal π-extension

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Chinese Chemical Letters 2024年第5期35卷 249-253页

作者： Jiaxiang Guo Zeyi li Tianyu Zhang Xinyu Tian Yue Wang chuandong Dou State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012China Jiangsu Engineering Laboratory of Novel Functional Polymeric Materials Soochow UniversitySuzhou 215123China

Quinoidalπ-conjugated structures,a kind of fundamental subunits for organicπ-systems,may produce some intriguing optical,electronic and magnetic properties of polycyclic hydrocarbons(PHs).Herein,we report two thienothiophene-centered ladder-type polycyclic molecules(1 and 2),which possess one quinoidal thienothiophene moiety and two para-quinodimethane(p-QDM)subunits,*** theoretically and experimentally studied,while 1 is a fully closed-shell molecule,2 owns an open-shell structure along with partial contribution of tetraradical state that is induced by the resonance of ***,although 2 has a largerπ-conjugated skeleton and open-shell electronic state,it exhibits larger bandgap and blue-shifted *** the other hand,the reversible oxidation activity of 1 enables the preparation of its dication 1^(2+),and the studies on its single-crystal and aromatic structures demonstrate that its two positive charges are delocalized onto the oxygen atoms,thus achieving fullyπ-extended structure and near-infrared *** study not only gains insight into quinoidalπ-subunits,but also provides an important basis for the development of antiaromatic and open-shellπ-electron materials.

关键词： Thienothiophene Quinoidal conjugation Open-shell structure Aromaticity Photophysical properties

Global synchronization of discrete-time coupled neural networks with Markovian switching and impulses

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生物数学学报：英文版 2016年第3期9卷 157-176页

作者： Jie Tan chuandong li College of Electronic and Information EngineeringSouthwest University Chongqing 400715 P. R. China College of Mathematics and PhysicsChongqing University of Science and Technology Chongqing 401331 P. R. China

This paper is concerned with the problem of synchronization analysis for discrete-time coupled neural networks. The networks under consideration are subject to: (1) the jumping parameters that are modeled as a continuous-time, discrete-state Markov process; (2) impulsive disturbances; and (3) time delays that include both the mode-dependent discrete and distributed delay. By constructing suitable Lyapunov–Krasovskii functional and combining with linear matrix inequality approach, several novel criteria are derived for verifying the global exponential synchronization in the mean square of such stochastic dynamical networks. The derived conditions are established in terms of linear matrix inequalities, which can be easily solved by some available software packages. A simulation example is presented to show the effectiveness and applicability of the obtained results.

关键词：耦合神经网络离散时间网络同步脉冲干扰 Lyapunov-Krasovskii泛函线性矩阵不等式方法切换马尔可夫过程

Bifurcation behaviors of an Euler discretized inertial delayed neuron model

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Science China(Technological Sciences) 2016年第3期59卷 418-427页

作者： HE Xing li chuandong HUANG TingWen YU JunZhi School of Electronics and Information Engineering Southwest University Chongqing 400715 China Texas A & M University at Qatar Doha 5825 Qatar State Key Laboratory of Management and Control for Complex Systems Institute of Automation Chinese Academy of Sciences Beijing 100190 China

This paper presents an Euler discretized inertial delayed neuron model, and its bifurcation dynamical behaviors are discussed. By using the associated characteristic model, center manifold theorem and the normal form method, it is shown that the model not only undergoes codimension one(flip, Neimark-Sacker) bifurcation, but also undergoes cusp and resonance bifurcation(1:1 and 1:2) of codimension two. Further, it is found that the parity of delay has some effect on bifurcation behaviors. Finally, some numerical simulations are given to support the analytic results and explore complex dynamics, such as periodic orbits near homoclinic orbits, quasiperiodic orbits, and chaotic orbits.

关键词：神经元模型分岔行为离散化时滞惯性欧拉中心流形理论同宿轨道

Global robust stability of complex-valued recurrent neural networks with time-delays and uncertainties

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International Journal of Biomathematics 2014年第2期7卷 79-102页

作者： Wei Zhang chuandong li Tingwen Huang College of Computer Science Chongqing UniversityChongqing 400044 P. R. China Department of MathematicsTexas A &M University at Qatar Qatar

This paper focuses on the existence, uniqueness and global robust stability of equilibrium point for complex-valued recurrent neural networks with multiple time-delays and under parameter uncertainties with respect to two activation functions. Two sufficient conditions for robust stability of the considered neural networks are presented and established in two new time-independent relationships between the network parameters of the neural system. Finally, three illustrative examples are given to demonstrate the theoretical results.

关键词：递归神经网络参数不确定性鲁棒稳定性多时滞激活功能充分条件时间无关网络参数