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coupling mechanism of mathematical models for sediment transport based on characteristic theory

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Science China(Technological Sciences) 2016年第11期59卷 1696-1706页

作者： DING Yun LI ZuiSen ZHONG DeYu KANG YanPing State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing 210098 China Zhejiang Institute of Hydraulics and Estuary Hangzhou 310008 China State Key Laboratory of Hydroscience and Engineering Tsinghua University Beijing 100084 China Jiangsu Hydraulic Research Institute Nanjing 210017 China

This paper aims to explore the coupling mechanism between flow movement, sediment transport and riverbed evolution in currently widely used mathematical models for sediment transport. Based on characteristic theory, analytic forms of eigenvalues,eigenvectors and characteristic relationships of total-sediment transport model, bed-load transport model and suspenedload transport model were derived, respectively. The singular perturbation technology was implemented to obtain the asymptotic solutions to different families of eigenvalues. The results indicate that, interactions between motion variables were explicitly coupled in the characteristics of total-sediment transport model and bed-load transport model. Further qualitative and quantitative analysis demonstrates that high sediment transport intensity and significant riverbed change will inevitably affect the property of flow movement. In the process of deposition, sediment-laden flow will move faster when sediment transport intensity becomes stronger. In contrast, the wave of flow will propagate at slower speed as erosion intensity becomes *** most existing suspended-load transport models, however, the characteristics are decoupled as the interactions between motion variables cannot be integrally illustrated in eigenvalues, eigenvectors and characteristic relationship.

关键词： coupling mechanism mathematical models sediment transport characteristics eigenvalues

coupling mechanism between Tamm Plasmon Polaritons and Monolayer WS_(2) Embedded in Metal/Dielectric Bragg Reflector Hybrid Architecture

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Journal of Wuhan University of Technology(Materials Science) 2021年第6期36卷 865-870页

作者： JIA Guangyi YUE Ke YANG Wenxin HUANG Zhenxian LIANG Qiqi LI Yin School of Science Tianjin University of CommerceTianjin 300134China

To reveal and utilize the interaction between Tamm plasmon polaritons(TPPs)and two-dimensional materials are promising for exploiting next-generation optoelectronic ***,the coupling mechanism between metal TPPs and monolayer WS_(2) along with its differences from that between metal TPPs and graphene was studied in detail by using the transfer matrix *** experimental results show that it is difficult to excite TPPs at the boundary between monolayer WS_(2) and dielectric Bragg reflector(DBR)such that the strong coupling mainly stems from the interaction between metal TPPs and exciton in monolayer WS_(2).However,the coupling in graphene/DBR/metal hybrid structure derives from the interaction between two different TPP resonance ***,evolutions of Rabi splitting with various structural parameters including spacer thickness,incident angle and DBR period greatly differ from those observed in graphene/DBR/metal hybrid *** addition,the discrepancies induced via metal Ag and Au films as well as the possible influence mechanism were also discussed.

关键词： Tamm plasmon polaritons monolayer WS_(2) Rabi splitting coupling mechanism

Epidemic Spreading–Information Dissemination coupling mechanism in Heterogeneous Areas

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Computers, Materials & Continua 2021年第6期67卷 3311-3327页

作者： Yang Yang Haiyan Liu Jianlin Zhou School of Economics and Management China University of Geosciences(Beijing)Beijing100083China

With COVID-19 continuing to rage around the world,there is a spread of epidemic-related information on social networking *** phenomenon may inhibit or promote the scale of epidemic *** study constructed a double-layer epidemic spreading–information dissemination network based on the movements of individuals across regions to analyze the dynamic evolution and coupling mechanism of information dissemination and epidemic *** also proposed measures to control the spread of the epidemic by analyzing the factors affecting dynamic *** constructed a state probability equation based on Markov chain theory and performed Monte Carlo simulations to demonstrate the interaction between information dissemination and epidemic *** simulation results showed that the higher the information dissemination rate,the larger the scale of information dissemination and the smaller the scale of epidemic *** addition,the higher the recovery rate of the epidemic or the lower the infection rate of the epidemic,the smaller the scale of information dissemination and the smaller the scale of epidemic ***,the greater the probability of individuals moving across regions,the larger the spread of the epidemic and ***,the higher the probability of an individual taking preventive behavior,the smaller the spread of the epidemic and ***,it is possible to suppress epidemic spread by increasing the information dissemination rate,epidemic recovery rate,and probability of individuals taking preventive behavior,while also reducing the infection rate of the epidemic and appropriately implementing regional blockades.

关键词： coupling mechanism moving and regional individuals heterogenous areas double-layer coupling network

Discussion on coupling mechanism of asymmetric CRLH/RH TL coupler

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第1期7卷 95-98页

作者：王佑贞张冶文赫丽刘富强李宏强陈鸿 School of Electronics and Information Tongji UniversityShanghai 200092 China School of Electronics and Information Tongji UniversityShanghai 200092 China Pohl Institute of Solid State Physics Tongji University Shanghai 200092 China Pohl Institute of Solid State Physics Tongji UniversityShanghai 200092 China

A quasi 0-dB coupler composed of a composite right-/left-handed transmission line (CRLH TL) and a conventional right-handed transmission line (RH TL) is presented. This coupler is shown to exhibit broad bandwidth and tight coupling char- acteristics. The circuit model and S-parameter results are also demonstrated. Another coupler with properly chosen loaded lumped-elements LL and CL in the CRLH TL is proposed to gain further understanding of the coupling mechanism. By adjusting the spacing between the CRLH TL and RH TL from 8 mm to 0.2 mm, it can be shown that backward coupling occurs in the left-handed region.

关键词： Asymmetric coupler coupling mechanism Composite right-/left-handed transmission line (CRLH TL)

The coupling mechanism between the suitable space and rural settlements considering the effect of mountain hazards in the upper Minjiang River basin

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Journal of Mountain Science 2020年第11期17卷 2774-2783页

作者： LIU Ying DENG Wei PENG Li The College of Geography and Resources Sichuan Normal UniversityChengdu 610101China

Some settlements were located in unsuitable regions due to limited land resources in mountainous areas,some settlements were even even constructed in areas prone to geological hazards in Southwest ***,it was important to evaluate the spatial appropriateness of a region and determine the areas that were unsuitable for settlements,and then find out the settlements located in unsuitable *** will assist in decision making associated with the relocation of ***,it will be the key to ensure the safety of inhabitants and promoting sustainable development in mountainous *** study explored the coupling mechanism between suitable space and rural settlements in the upper Minjiang River basin,which is an ecologically fragile area with high-frequency of natural ***,we identified relief degree of land surface(RDLS),elevation,and disaster risk as the limiting ***,by determining the thresholds of these limiting factors,we recognized the suitable areas for inhabitation in the upper Minjiang River basin with ***,using the distribution map of rural settlements and that of suitable space,the distribution of rural settlements located at unsuitable area was obtained by coupling relationship ***,an in-depth understanding of this relationship was achieved as follows:(1)The suitable space of the upper Minjiang River basin is 13.7 thousand km2,accounting for 54.9%of the total land space;(2)There were 196 settlements located in the unsuitable area,the total area of these settlements was 125.27 km2,and there were 68000 people in these settlements,accounting for 17.65%of the total population;(3)There were 65 settlements located near mountain hazard areas,accounting for 4.9%of the *** findings suggest that it was necessary to carefully investigate settlements with risks and develop targeted relocation policies to help find the most effective way of using land safely and to good *** details

关键词： coupling mechanism Sustainable Development Remote Sensing China

A possible coupling mechanism between magnetism and dielectric properties in EuTiO3

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Chinese Physics B 2002年第12期11卷 1303-1306页

作者：蒋青吴华 DepartmentofPhysics SuzhouUniversitySuzhou215006China

The dielectric constant of an incipient ferroelectric EuTiO3 exhibits a sharp decrease at about 5.5K, at which the antiferromagnetic ordering of the Eu spins simultaneously appears. This fact indicates the existence of a coupling between the magnetism and dielectric properties of EuTiO3. We propose a possible coupling mechanism between the magnetic and electrical subsystems as -gIn the framework of soft-mode theory, we have obtained analytically a dielectric constant expression related to the spin correlation of nearest neighbours of Eu ions.

关键词： coupling mechanism magnetism dielectric property soft-mode theory

The coupling characteristics and mechanism of farmland and rural housing land transition in China

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Journal of Geographical Sciences 2012年第3期22卷 548-562页

作者： Long Hualou Li Tingting Institute of Geographic Sciences and Natural Resources Research CAS Key Laboratory of Regional Sustainable Development Modeling CAS Graduate University of Chinese Academy of Sciences

Land use transition refers to the changes in land use morphology （both dominant morphology and recessive morphology） of a certain region over a certain period of time driven by socio-economic change and innovation, and it usually corresponds to the transition of socio-economic development phase. In China, farmland and rural housing land are the two major sources of land use transition. This paper analyzes the spatio-temporal coupling characteristics of farmland and rural housing land transition in China, using high-resolution Landsat TM （Thematic Mapper） data in 2000 and 2008, and the data from the Ministry of Land and Resources of China. The outcomes indicated that：（1） during 2000-2008, the correlation coefficient of farmland vs. rural housing land change is -0.921, and it shows that the change pattern of farmland and rural housing land is uncoordinated; （2） the result of Spearman rank correlation analysis shows that rural housing land change has played a major role in the mutual transformation of farmland and rural housing land; and （3） it shows a high-degree spatial coupling between farmland and rural housing land change in southeast China during 2000-2008. In general, farmland and rural housing land transition in China is driven by socio-economic, bio-physical and managerial three-dimensional driving factors through the interactions among rural population, farmland and rural housing land. However, the spatio-temporal coupling phenomenon and mechanism of farmland and rural housing land transition in China are largely due to the ＂dual-track＂ structure of rural-urban development.

关键词： land use transition farmland rural housing land coupling mechanism rural transformation development China

coupling and coordinated evolution characteristics of regional economy-energy-carbon emission multiple systems:A case study of main China's Basin

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Journal of Environmental Sciences 2024年第6期140卷 204-218页

作者： Lu Chen Xin Li Jingyi Zhao Xinyu Kang Lu Liu Minxi Wang Wu Chen College of Management Science Chengdu University of TechnologyChengdu 610051China SDU Life Cycle Engineering Department of Green TechnologyUniversity of Southern Denmark5230 OdenseDenmark

Comprehensive analysis of the Economy-Energy-Carbon Emission(EECE)system is beneficial for promoting sustainable social *** study analyzes the system development of major watersheds in China from 2010 to *** research fully considers the system’s internal and external inputs and outputs and proposes an evaluation index system for regional EECE coupling and coordinated ***,using the difference in system weight allocation to improve the coupling and coordination model,the study explores the dynamic system’s coupling and *** results show that(1)The development of the system structure is relatively stable,but the overall development status is not ideal;(2)The downstream of China’s main river basins has obvious economic advantages,while the energy system fluctuates *** efficiency of the carbon emission system will decrease in areas with rapid economic *** coupling and coordination level of the EECE system is better in the Yangtze River Basin than in the Yellow River Basin;(3)From the perspective of dynamic coordinated development,the main river basins have been divided into two states since 2012,but it is relatively stable *** dynamic coordination is often at a disadvantage in regions with rapid economic and energy development;(4)The coupling coordination degree of the two river basins has significant positive spatial *** provinces’significant spatial clustering characteristics of the coupling coordination degree are High-High ***-Low type provinces are mainly concentrated *** research process has certain reference significance for the collaborative governance of complex regional systems.

关键词： System structure Efficiency measure coupling mechanism Dynamic coordination

Research on the coupling mechanism of Creative Spirit Cultivation and Scientific and Technological Innovation Development

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Journal of Contemporary Educational Research 2021年第8期5卷 155-160页

作者： Ning Wang Library The Party School of Anhui Provincial Committee(Anhui Administrative College)Hefei 230059AnhuiChina

Migration and innovation is the driving force of scientific and technological *** analyzing the coupling relationship between the two,this paper finds out the common elements shared by the two factors,and constructs the coupling guarantee mechanism between them,so as to provide suggestions for the coordination,win-win and synchronous benign development of the spirit of makers and the development of scientific and technological innovation,and promote the sustainable development of the national innovation system.

关键词： Maker spirit Nurture Scientific and technological innovation and development coupling mechanism Path