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Water quality monitoring and evaluation using remote sensing techniques in China:a systematic review 被引量:18
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作者 Xiaoyan Wang Wu Yang 《Ecosystem Health and Sustainability》 SCIE 2019年第1期47-56,I0023,共11页
Introduction:The application of remote-sensing techniques for water quality assessment has become increasingly popular in China.However,existing reviews are often limited to qualitative description and are quite fragm... Introduction:The application of remote-sensing techniques for water quality assessment has become increasingly popular in China.However,existing reviews are often limited to qualitative description and are quite fragmented.Outcomes:We conducted a quantitative systematic review to display current research status and identify the existing challenges and future directions.Our review revealed that the application of remote-sensing techniques in water quality research has expanded dramatically in China,but the spatial distribution is quite uneven.Second,the ground object spectrometer is the most widely applied data source.Water color indicators such as chlorophyll a and suspended solid are the most widely investigated in China.Third,semiempirical method is the most commonly used inversion method.Existing studies rarely considered the anthropogenic factors,which limited the model robustness and its application in humandominated aquatic ecosystems.Discussion and Conclusion:We concluded that,in the past several decades,China has made notable progresses in monitoring and evaluation of water quality using the remote-sensing techniques(especially in inland lakes).We proposed that further improvements would be needed in terms of temporal and spatial coverage,indicator list,the incorporation of human–nature interactions,inversion accuracy,and model generalization. 展开更多
关键词 Chlorophyll a coupled human and natural systems inversion algorithm suspended solid water quality indicators water resource management
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光测弹性理论中的耦联变分原理和广义耦联变分原理 被引量:14
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作者 付宝连 《应用数学和力学》 EI CSCD 北大核心 1996年第1期39-44,共6页
在本文中,应用拉格朗日乘子法和高阶拉格朗日乘子法[1],我们系统地导出了光测弹性理论中的耦联势能原理,耦联余能原理和具有二类和三类变量的广义耦联势能原理和广义相联余能原理.
关键词 耦联系统 耦联变分原理 光测弹性理论 广义
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耦合系统中时空混沌的神经网络控制方法 被引量:6
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作者 汪小帆 王执铨 宋文忠 《控制理论与应用》 EI CAS CSCD 北大核心 1999年第2期283-287,共5页
以耦合映象链模型为例 ,利用神经网络的学习能力 ,提出了一种控制耦合系统的时空混沌行为的方法 。
关键词 耦合系统 时空混沌 神经网络 自动控制
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基于多学科设计的复杂机电系统并行设计方法研究 被引量:7
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作者 李旭宇 钟掘 《机械与电子》 2002年第6期29-31,共3页
针对目前复杂机电系统设计采用各学科分离进行子系统串行设计的现状,在分析机电系统耦合特征的基础上,应用国外刚兴起的一种设计方法多学科设计方法进行复杂机电系统的设计。分析了复杂机电系统并行设计的实施基本过程。
关键词 并行设计 复杂机电系统 耦合系统 多学科设计
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内蒙古半干旱生态脆弱矿区生态修复耦合机理与产业模式 被引量:13
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作者 陈玉碧 黄锦楼 +4 位作者 徐华清 赵波 陈文虾 程冠全 马慧君 《生态学报》 CAS CSCD 北大核心 2014年第1期149-153,共5页
近年,煤炭开采带动矿区经济发展的同时也造成了严重的生态环境问题。由此产生生态修复和土地复垦产业延伸的生态环境治理和矿区产业调整优化方面研究热点,二者形成的耦合系统可在恢复受损土地的同时,以治理和循环生产为契机延伸产业链... 近年,煤炭开采带动矿区经济发展的同时也造成了严重的生态环境问题。由此产生生态修复和土地复垦产业延伸的生态环境治理和矿区产业调整优化方面研究热点,二者形成的耦合系统可在恢复受损土地的同时,以治理和循环生产为契机延伸产业链。受损地形重塑及边开采边恢复技术开发及应用形成安全稳定地形条件是前提,其次是土壤的恢复重构,在当地条件下迅速恢复具备良好理化性质,供植被和经济能源作物生长和景观格局构建,最终形成修复产业和生态产业的价值创造平台。根据耦合系统的工艺特点,每年内蒙矿区利用该耦合系统以矿区受损土地修复进行循环生产生态修复产品的潜力约21915.51万吨和经济能源作物的潜力约21.15万t。 展开更多
关键词 生态修复 产业模式 耦合系统 潜力分析
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时滞耦合系统动力学的研究进展 被引量:8
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作者 茅晓晨 《动力学与控制学报》 2017年第4期295-306,共12页
综述了近年来时滞耦合系统动力学的研究进展,重点阐述了稳定性与分岔、同步以及复杂动力学等方面的一些理论和方法的研究结果,对进一步的研究工作提出了若干展望.
关键词 时滞 耦合系统 非线性 稳定性 分岔 同步 复杂动力学
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塑性硬化材料耦联系统的变分原理及其在塑性加工中的应用 被引量:7
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作者 任运来 郭宝锋 +1 位作者 秦泗吉 肖凯伯 《塑性工程学报》 CAS CSCD 1997年第1期14-20,共7页
本文针对塑性加工中最常见的塑性硬化材料模型,建立了其耦联系统的变分原理,并应用耦联系统的势能原理分析了镦粗变形工序。
关键词 耦联系统 塑性硬化材料 变分 金属 塑性变形
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细胞丛状化分布对二维耦合体系尺度选择效应的影响 被引量:6
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作者 申传胜 张季谦 陈含爽 《物理学报》 SCIE EI CAS CSCD 北大核心 2007年第11期6315-6320,共6页
采用随机模拟方法对体系的化学朗之万方程进行了数值模拟,考察了二维耦合细胞体系中,细胞的丛状化分布对于因内噪声作用而产生的尺度选择效应所带来的影响.研究发现,当体系处于Hopf分岔点附近时,由于耦合作用使得处于最佳状态的一定数... 采用随机模拟方法对体系的化学朗之万方程进行了数值模拟,考察了二维耦合细胞体系中,细胞的丛状化分布对于因内噪声作用而产生的尺度选择效应所带来的影响.研究发现,当体系处于Hopf分岔点附近时,由于耦合作用使得处于最佳状态的一定数目的细胞呈现丛状化聚集在一起,而这种丛状化分布的"团队精神"可以极大地提高体系的工作效率,表现为体系对外界刺激信号的响应能力(信噪比)达到极大值.同时还观察到,体系对外界刺激最为敏感时对应的最佳细胞丛尺度大小不随耦合强度的改变而变化,而体系输出信号的信噪比,随着耦合强度的增加有增大趋势.这些现象表明,细胞的丛状化分布将极大地增强细胞中钙离子信号对外界刺激的响应效果.生物体系本身可能具有这种特性,并利用它来改善和提高感受外界信息的能力. 展开更多
关键词 内噪声 耦合体系 体系尺度选择效应 团队精神
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Effects of fracture evolution and non-Darcy flow on the thermal performance of enhanced geothermal system in 3D complex fractured rock
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作者 Yachen Xie Jianxing Liao +2 位作者 Pengfei Zhao Kaiwen Xia Cunbao Li 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第4期443-459,共17页
In fractured geothermal reservoirs,the fracture networks and internal fluid flow behaviors can significantly impact the thermal performance.In this study,we proposed a non-Darcy rough discrete fracture network(NR-DFN)... In fractured geothermal reservoirs,the fracture networks and internal fluid flow behaviors can significantly impact the thermal performance.In this study,we proposed a non-Darcy rough discrete fracture network(NR-DFN)model that can simultaneously consider the fracture evolution and non-Darcy flow dynamics in studying the thermo-hydro-mechanical(THM)coupling processes for heat extraction in geothermal reservoir.We further employed the model on the Habanero enhanced geothermal systems(EGS)project located in Australia.First,our findings illustrate a clear spatial-temporal variation in the thermal stress and pressure perturbations,as well as uneven spatial distribution of shear failure in 3D fracture networks.Activated shear failure is mainly concentrated in the first fracture cluster.Secondly,channeling flow have also been observed in DFNs during heat extraction and are further intensified by the expansion of fractures driven by thermal stresses.Moreover,the combined effect of non-Darcy flow and fracture evolution triggers a rapid decline in the resulting heat rate and temperature.The NR-DFN model framework and the Habanero EGS's results illustrate the importance of both fracture evolution and non-Darcy flow on the efficiency of EGS production and have the potential to promote the development of more sustainable and efficient EGS operations for stakeholders. 展开更多
关键词 coupled THM model Non-Darcy flow Deformable DFN Enhanced geothermal systems
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From decoupled integrable models to coupled ones via a deformation algorithm
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作者 杜文鼎 孔德兴 楼森岳 《Communications in Theoretical Physics》 SCIE CAS CSCD 2023年第10期38-44,共7页
By using a reconstruction procedure of conservation laws of different models,the deformation algorithm proposed by Lou,Hao and Jia has been used to a new application such that a decoupled system becomes a coupled one.... By using a reconstruction procedure of conservation laws of different models,the deformation algorithm proposed by Lou,Hao and Jia has been used to a new application such that a decoupled system becomes a coupled one.Using the new application to some decoupled systems such as the decoupled dispersionless Korteweg–de Vries(Kd V)systems related to dispersionless waves,the decoupled KdV systems related to dispersion waves,the decoupled KdV and Burgers systems related to the linear dispersion and diffusion effects,and the decoupled KdV and Harry–Dym(HD)systems related to the linear and nonlinear dispersion effects,we have obtained various new types of higher dimensional integrable coupled systems.The new models can be used to describe the interactions among different nonlinear waves and/or different effects including the dispersionless waves(dispersionless KdV waves),the linear dispersion waves(KdV waves),the nonlinear dispersion waves(HD waves)and the diffusion effect.The method can be applied to couple all different separated integrable models. 展开更多
关键词 integrable systems deformation algorithm KdV equations higher dimensional integrable systems coupled and decoupled systems
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计及综合需求响应的电力天然气耦合系统经济调度
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作者 马伟哲 程维杰 +2 位作者 龚晨 翁毅选 谷若雨 《电气应用》 2023年第2期102-106,共5页
为解决电力天然气耦合系统波动问题,计及需求响应在耦合系统中的影响,提出了基于需求响应的耦合系统经济调度。分析了天然气电力耦合系统的基本组成和能量流动,建立了电力天然气联合系统的优化调度模型,模型中考虑需求响应约束,同时分... 为解决电力天然气耦合系统波动问题,计及需求响应在耦合系统中的影响,提出了基于需求响应的耦合系统经济调度。分析了天然气电力耦合系统的基本组成和能量流动,建立了电力天然气联合系统的优化调度模型,模型中考虑需求响应约束,同时分别考虑天然气系统约束中的常规约束和压缩机约束,提出电力天然气系统在含有需求响应时的可行域,利用仿真分析说明需求响应在削减成本、电力负荷优化方面的作用。 展开更多
关键词 需求响应 天然气系统 耦合系统 压缩机模型
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Stability of Coupled Impulsive Markovian Jump Reaction-Diffusion Systems on Networks 被引量:4
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作者 LI Yanbo KAO Yonggui 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2016年第5期1269-1280,共12页
This paper is devoted to the investigation of stability for a class of coupled impulsive Markovian jump reaction-diffusion systems on networks(CIMJRDSNs). By using graph theory, a systematic method is provided to cons... This paper is devoted to the investigation of stability for a class of coupled impulsive Markovian jump reaction-diffusion systems on networks(CIMJRDSNs). By using graph theory, a systematic method is provided to construct global Lyapunov functions for the CIMJRDSNs. Based on Lyapunov functions and stochastic analysis method, some novel stability principles associated with the topology property of the networks are established. 展开更多
关键词 coupled stochastic reaction-diffusion systems impulsive Markovian switching NETWORKS stability.
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拉氏乘子法和耦联变分原理 被引量:3
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作者 付宝连 《东北重型机械学院学报》 1991年第1期59-63,共5页
本文利用拉氏乘子法系统地导出了耦联势能和余能原理。
关键词 拉氏乘子法 耦联系统 变分原理
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Solitonic attractors in the coupled nonlinear Schrödinger equations with weak dissipations
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作者 Kai-Yuan Qi Xian-kun Yao +1 位作者 Li-Chen Zhao Zhan-Ying Yang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2023年第6期22-26,共5页
We use the Lagrangian perturbation method to investigate the properties of soliton solutions in the coupled nonlinear Schrödinger equations subject to weak dissipation.Our study reveals that the two-component sol... We use the Lagrangian perturbation method to investigate the properties of soliton solutions in the coupled nonlinear Schrödinger equations subject to weak dissipation.Our study reveals that the two-component soliton solutions act as fixed-point attractors,where the numerical evolution of the system always converges to a soliton solution,regardless of the initial conditions.Interestingly,the fixed-point attractor appears as a soliton solution with a constant sum of the two-component intensities and a fixed soliton velocity,but each component soliton does not exhibit the attractor feature if the dissipation terms are identical.This suggests that one soliton attractor in the coupled systems can correspond to a group of soliton solutions,which is different from scalar cases.Our findings could inspire further discussions on dissipative-soliton dynamics in coupled systems. 展开更多
关键词 coupled nonlinear systems weak dissipation solitonic attractor
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全局灵敏性分析方法的研究 被引量:4
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作者 谷良贤 仇理宽 龚春林 《航空计算技术》 2011年第1期1-4,13,共5页
全局灵敏性分析是解决多学科优化中复杂耦合系统的重要方法,对全局灵敏性分析技术进行了论述,基于一阶模型,建立了二阶以及高阶导数模型,发展了全局敏感性计算方法。编制了基于梯度的优化算法,并与全局灵敏度方程(GSE)求得的导数信息融... 全局灵敏性分析是解决多学科优化中复杂耦合系统的重要方法,对全局灵敏性分析技术进行了论述,基于一阶模型,建立了二阶以及高阶导数模型,发展了全局敏感性计算方法。编制了基于梯度的优化算法,并与全局灵敏度方程(GSE)求得的导数信息融合,进行了实例应用。与多种优化方法进行了比较,证明了设计方法的可行性、优越性。 展开更多
关键词 多学科优化 全局灵敏度分析 耦合系统
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Vibrational resonance in globally coupled bistable systems under the noise background
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作者 刘江令 李朝润 +1 位作者 高海玲 杜鲁春 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第7期303-307,共5页
Effects of system size,coupling strength,and noise on vibrational resonance(VR)of globally coupled bistable systems are investigated.The power spectral amplifications obtained by the three methods all show that the VR... Effects of system size,coupling strength,and noise on vibrational resonance(VR)of globally coupled bistable systems are investigated.The power spectral amplifications obtained by the three methods all show that the VR exists over a wide range of parameter values.The increase in system size induces and enhances the VR,while the increase in noise intensity suppresses and eventually eliminates the VR.Both the stochastic resonance and the system size resonance can coexist with the VR in different parameter regions.This research has potential applications to the weak signal detection process in stochastic multi-body systems. 展开更多
关键词 vibrational resonance globally coupled bistable systems power spectral amplification noise
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Reducing environmental impacts through socioeconomic transitions:critical review and prospects
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作者 Sai Liang Qiumeng Zhong 《Frontiers of Environmental Science & Engineering》 SCIE EI CSCD 2023年第2期123-143,共21页
Rapid socioeconomic development has caused numerous environmental impacts.Human production and consumption activities are the underlying drivers of resource uses,environmental emissions,and associated environmental im... Rapid socioeconomic development has caused numerous environmental impacts.Human production and consumption activities are the underlying drivers of resource uses,environmental emissions,and associated environmental impacts(e.g.,ecosystem quality and human health).Reducing environmental impacts requires an understanding of the complex interactions between socioeconomic system and environmental system.Existing studies have explored the relationships among human society,economic system,and environmental system.However,it is unclear about the research progress in the effects of socioeconomic activities on environmental impacts and the potential directions of future research.This critical review finds that existing studies have identified critical regions,sectors,and transmission pathways for resource uses,environmental emissions,and environmental impacts from supply chain perspectives.Moreover,scholars have characterized the impacts of socioeconomic transitions on resource uses and environmental emissions.However,existing studies overlook the dynamic nature of the interconnections among human society,economic system,and environmental system.In addition,the effects of socioeconomic structural transitions on environmental impacts remain unknown.This review proposes four prospects and possible solutions that will contribute to a better understanding of the complex interactions among human society,economic system,and environmental system.They can help identify more effective solutions to reduce environmental impacts through socioeconomic transitions. 展开更多
关键词 Environmental pressures Environmental impacts NEXUS Supply chains TRADE coupled systems
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Boundary Control of Coupled Non-Constant Parameter Systems of Time Fractional PDEs with Different-Type Boundary Conditions
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作者 CHEN Juan ZHUANG Bo 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2023年第1期273-293,共21页
This paper addresses a boundary state feedback control problem for a coupled system of time fractional partial differential equations(PDEs)with non-constant(space-dependent)coefficients and different-type boundary con... This paper addresses a boundary state feedback control problem for a coupled system of time fractional partial differential equations(PDEs)with non-constant(space-dependent)coefficients and different-type boundary conditions(BCs).The BCs could be heterogeneous-type or mixed-type.Specifically,this coupled system has different BCs at the uncontrolled side for heterogeneous-type and the same BCs at the uncontrolled side for mixed-type.The main contribution is to extend PDE backstepping to the boundary control problem of time fractional PDEs with space-dependent parameters and different-type BCs.With the backstepping transformation and the fractional Lyapunov method,the Mittag-Leffler stability of the closed-loop system is obtained.A numerical scheme is proposed to simulate the fractional case when kernel equations have not an explicit solution. 展开更多
关键词 Boundary control coupled systems HETEROGENEOUS mittag-leffler stability time fractional PDEs with space-dependent coefficients
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Periodic electron oscillation in coupled two-dimensional lattices
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作者 陆艳艳 王超 +2 位作者 将金益 刘洁 钟建新 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第7期142-149,共8页
We study the time evolution of electron wavepacket in the coupled two-dimensional(2D)lattices with mirror symmetry,utilizing the tight-binding Hamiltonian framework.We show analytically that the wavepacket of an elect... We study the time evolution of electron wavepacket in the coupled two-dimensional(2D)lattices with mirror symmetry,utilizing the tight-binding Hamiltonian framework.We show analytically that the wavepacket of an electron initially located on one atomic layer in the coupled 2D square lattices exhibits a periodic oscillation in both the transverse and longitudinal directions.The frequency of this oscillation is determined by the strength of the interlayer hopping.Additionally,we provide numerical evidence that a damped periodic oscillation occurs in the coupled 2D disordered lattices with degree of disorderW,with the decay time being inversely proportional to the square ofW and the frequency change being proportional to the square of W,which is similar to the case in the coupled 1D disordered lattices.Our numerical results further confirm that the periodic and damped periodic electron oscillations are universal,independent of lattice geometry,as demonstrated in AA-stacked bilayer and tri-layer graphene systems.Unlike the Bloch oscillation driven by electric fields,the periodic oscillation induced by interlayer coupling does not require the application of an electric field,has an ultrafast periodicity much shorter than the electron decoherence time in real materials,and can be tuned by adjusting the interlayer coupling.Our findings pave the way for future observation of periodic electron oscillation in material systems at the atomic scale. 展开更多
关键词 quantum diffusion periodic oscillation coupled systems DISORDER Anderson localization
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THE VARIATIONAL PRINCIPLES OF COUPLED SYSTEMS IN PHOTOELASTICITY 被引量:1
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作者 付宝连 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1994年第1期37-48,共12页
This paper presents an energy principle, zero different principle of coupledsystems in photoelasticity, from which the potential energy, the complementary energy,generalized potential energy and generalized complemen... This paper presents an energy principle, zero different principle of coupledsystems in photoelasticity, from which the potential energy, the complementary energy,generalized potential energy and generalized complementary energy variationalprinciples of the coupled systems in photoelasticity are derived What is called the coupled systems means that two deformational bodies, forwhich figures, sizes,loads and boundary conditions are the same and they are all inactual states but they are made of different materials.Prototype body and model body in photoelasticity are essentially the coupledsystems, therefore the above principles become the theoretical basis of defining theinflunce of Poissons ratio v on accuracy of the frozen-stress method. 展开更多
关键词 PHOTOELASTICITY coupled systems zero different work principle coupled variational principle
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