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spatial coupling Relationship and Driving Mechanism of Population and Economy in Rural Areas in Qinling-Daba Mountains,China

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Chinese Geographical Science 2023年第5期33卷 779-795页

作者： XIAO Jie QIAO Jiajun HAN Dong LIU Yang PAN Tao Key Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions Henan UniversityKaifeng 475004China College of Geography and Environmental Science Henan UniversityKaifeng 475004China Ministry of Education National Demonstration Center for Environment and PlanningHenan UniversityKaifeng 475004China Henan Natural Resources Research Institute Zhengzhou 450000China

Addressing the issue of the healthy and coordinated development of the population and economic factors in rural areas will not only help consolidate and expand the achievements of poverty alleviation,but will also lay a foundation for comprehensive rural *** this paper,the spatial coupling relationship between the population and economic factors in rural areas in the QinlingDaba Mountains,China,is explored to provide a reference for rural revitalization and regional sustainable development in poverty ***-eight county units in rural areas in the Qinling-Daba Mountains,as well as the population and economic factors in rural areas,are used to study the spatial coupling relationship between population and economy,as well as the driving mechanism,in rural areas in the Qinling-Daba Mountains from 2010 to *** results show that a population contraction phenomenon occurred in the rural areas in the Qinling-Daba Mountains,and the spatial agglomeration trends of the population and economic factors were *** agglomeration was mainly located in the suburban areas of the municipal area,and the agglomeration degree was significantly higher in these areas than in other *** terms of the spatial distribution,the economic development level of the rural areas in the northeastern part of the Qinling-Daba Mountains was generally higher than that in the central and western parts,and the unbalanced trends of the population and economic spatial differentiation in the eastern and western regions were *** spatial coupling relationship between the population and economy changed from coordinated development to economic *** was mainly due to the mutual restriction and joint actions of the industrial structure,capital situation,natural environment,policies,and institutional regulations,among which the industrial structure and capital status had significant effects.

关键词： rural poverty population distribution economic development pattern spatial coupling influencing factors rural revitalization Qinling-Daba Mountains,China

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Effects of the spatial coupling of Water and Fertilizer on the Chlorophyll Fluorescence Parameters of Winter Wheat Leaves

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Agricultural Sciences in China 2011年第12期10卷 1923-1931页

作者： SHEN Yu-fang LI Shi-qing State Key Laboratory of Soil Erosion and Dryland Farming on Loess Plateau/Northwest A＆F University Yangling 712100 P.R.China

Wheat is an important agricultural crop in the Loess region of China, where there is drought stress and low availability of soil nitrogen and phosphorus. Using a pulse modulation fluorometer, we studied the effects of water, nitrogen, and phosphorus on the kinetic parameters of chlorophyll fluorescence in winter wheat. The wheat was grown in layered columns of Eum-Orthic Anthrosol （Cinnamon soil）, with the water content and nutrient composition of each layer controlled. The results showed that the kinetic parameters of chlorophyll fluorescence were sensitive to water stress. The basic fluorescence （F0） of leaves was higher in the dry treatment （0-30 cm layer at 40-45% of field capacity, 30-90 cm at 75-80% of field capacity） compared to the wet treatment （entire soil column at 75-80% of field capacity）. The maximal fluorescence （Fm）, the variable fluorescence （Fv）, the photochemical efficiency （Fv/Fm） and potential activites （Fv/F0） of photosystem 2 （PS2） were significantly lower in the dry treatment. Although drought stress impaired PS2 function, this effect was significantly ameliorated by applying P or NP fertilizer, but not N alone. P application increased FJFm, both in well-watered and water stressed plants, especially when fertilizer was applied throughout the column or within the top 30 em of soil. A combined fertilizer improved photosynthesis in well watered plants, with Fm and F,fFm being the highest when fertilizer was applied throughout the columns. For drought stressed, plants FJFm was significantly greater when combined fertilizer was added within the top 30 cm of soil. We concluded that, when growing winter wheat in both arid and semi-arid parts of the Loess region of China, it is important to guarantee the nutrient supply in the top 30 cm of the soil.

关键词： water stress nutrient spatial coupling chlorophyll fluorescence column experiment

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The spatial coupling characteristics between the construction of Qingzang National Park Cluster and the sustainable development of local communities

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Geography and Sustainability 2021年第1期2卷 1-11页

作者： Rui Guo Dong Chen Daojing Zhou Baoyin Liu Hanchu Liu Yannan Zhao Yong Sun Jie Fan Institutes of Science and Development Chinese Academy of SciencesHaidian DistrictBeijing 100190China University of Chinese Academy of Sciences Shijingshan DistrictBeijing 100049China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesChaoyang DistrictBeijing 100101China

The development of Qingzang national park cluster is part of China’s efforts to establish a major ecological civi-lization project in the Qingzang Plateau,in line with global sustainable development *** on preliminary scientific investigation and research in the Qingzang Plateau,the construction of the park cluster will include 21 national *** mitigate the conflict between conservation of the national park cluster and the develop-ment of local communities,this study proposes an analysis framework to identify the spatial coupling features between the national park cluster and sustainable development of *** elements were selected to construct the analysis framework,including natural conditions,geographic location,cultural background,and national *** framework was applied to the 457 township communities within the 21 national *** show the weak influence of the construction of the national park cluster for approximately 304 township communities,without significant spatial coupling traits,while the remaining 153 communities demonstrated significant spatial coupling *** latter townships had developed four types of spatial coupling with na-tional parks,including eco-migrants,transportation hubs,characteristic cultures,and border development,which account for 17.4%,35.3%,19.8%,and 27.5%of the 153 townships respectively.A composite type with more than one spatial coupling feature was also found for 14 communities within the 153 *** provides a reference for policy making towards four major types of interactive modes between townships and the national park construction for the sustainable development of Qingzang Plateau.

关键词： Qingzang Plateau National park(cluster) Community spatial coupling Sustainable development

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Study on the spatial coupling between Expressway Networks and Tourist Attractions: A Case Study of Guizhou Province

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Chinese Journal of Urban and Environmental Studies 2020年第1期8卷 17-36页

作者： CHEN Sihong XI Jianchao LIU Menghao Key Laboratory of Regional Sustainable Development Modeling Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences College of Resource and Environment University of Chinese Academy of Sciences

Transportation is the most basic element in the development of tourism, with expressways being the main channel for tourism transportation in the era of driving tours. The relationship between transportation and tourism development has always been one of the hot topics in tourism geography study. Since the expressway service area is the main node of tourist service facilities in the expressway transportation network, we conducted a field research on 125 service areas and 177 tourist attractions in Guizhou Province, and obtained relevant data. By using the centrality measures for social network analysis, and combining the kernel density analysis with bivariate spatial autocorrelation analysis, this paper explores the centrality characteristics of expressway transportation network, the spatial distribution regularity of tourist attractions, and the spatial coupling between them. The main study conclusions are as follows:(1) The expressway service areas in Guizhou Province gradually decrease from a single core to the periphery.(2) The spatial distribution of tourist attractions presents a weak circular structure with multiple cores in a scattered manner, and the regional differences are apparent.(3) There is positive spatial correlation between the expressway networks and tourist attractions. The spatial coupling between the expressway transportation network and tourist attractions can be divided into four types of clusters:high–high cluster, high–low cluster, low–high cluster, and low–low cluster, with high–high and low–low clusters as the main types. The high–high cluster is the area with the best coupling effect and the most mature tourism. The high–low and low–high clusters have a mismatch between transportation and tourism resources. For such clusters, the spatial coupling can be realized by changing the functions of the service area or improving the quality of the tourist attraction. They have great development potential. The low–low cluster is far away from tour

关键词： Expressway tourist attraction network centrality spatial coupling transportation and tourism integration

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Asynchronous multilevel bit-interleaved polar-coded modulation

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Science China(Information Sciences) 2023年第3期66卷 263-272页

作者： Yaoyue HU Zhiwen PAN Yongliang GUAN National Mobile Communications Research Laboratory Southeast University Purple Mountain Laboratories School of Electrical and Electronic Engineering Nanyang Technological University

Asynchronous bit-interleaved polar-coded modulation(A-BIPCM) provides high performance gain over conventional synchronous polar-coded modulation schemes at the expense of higher storage and decoding complexity. To overcome this drawback, this paper proposes a low-complexity polar-coded modulation, referred to as asynchronous multilevel bit-interleaved polar-coded modulation(A-MLBIPCM). The proposed A-MLBIPCM combines spatial coupling and the multilevel structure on polar-coded *** analyzing the polarization diversity and storage complexity of the system, optimal encoding and modulation patterns are proposed to maintain the polarization diversity and reduce the storage *** results show that A-MLBIPCM provides better block-error-rate(BLER) performance than multilevel polar-coded modulation(MLPCM). Compared with A-BIPCM, the proposed scheme delivers about 23.84%–27.34% savings in storage and up to 33.02% savings in calculation complexity with almost no penalty in BLER(the difference is less than 0.1 dB).

关键词： polar codes bit-interleaved coded modulation multilevel coded modulation spatial coupling multi-stage decoding

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spatially Coupled Codes via Bidirectional Block Markov Superposition Transmission

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Tsinghua Science and Technology 2024年第3期29卷 656-670页

作者： Gaoyan Li Shancheng Zhao Haiqiang Chen Jinming Wen College of Information Science and Technology Jinan UniversityGuangzhou 510632China Guangxi Key Laboratory of Multimedia Communications and Network Technology Guangxi UniversityNanning 530004China

In this paper,we present a new class of spatially coupled codes obtained by using both non-recursive and recursive block-oriented *** resulting codes are termed as bidirectional block Markov superposition transmission(BiBMST)***,we perform an iterative decoding threshold analysis according to protograph-based extrinsic information transfer(PEXIT)charts for the BiBMST codes over the binary erasure channels(BECs).Secondly,we derive the generator and parity-check matrices of the BiBMST ***,extensive numerical results are presented to show the advantages of the proposed BiBMST ***,our numerical results show that,under the constraint of an equal decoding latency,the BiBMST codes perform better than the recursive BMST(rBMST)***,the simulation results show that,in finite-length regime,negligible performance gain is obtained by increasing the encoding *** solve this limitation by introducing partial superposition,and the resulting codes are termed as partially-connected BiBMST(PC-BiBMST)*** results have confirmed the advantages of the PC-BiBMST codes over the original BiBMST *** also present extensive simulation results to show the performance advantages of the PC-BiBMST codes over the spatially coupled low-density parity-check(SC-LDPC)codes,spatially coupled generalized LDPC(SC-GLDPC)codes,and the original BiBMST codes in the finite-length regime.

关键词： block Markov superposition transmission(BMST) protograph-based extrinsic information transfer(PEXIT) capacity-approaching codes spatial coupling

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Analysis of irregular repetition spatially-coupled slotted ALOHA

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Science China(Information Sciences) 2019年第8期62卷 22-34页

作者： Hanxiao YU Zesong FEI Congzhe CAO Ming XIAO Dai JIA Neng YE School of Information and Electronics Beijing Institute of Technology Department of Electrical and Computer Engineering University of Alberta School of Electrical Engineering KTH Royal Institute of Technology

Contention-based access is a promising technology for massive and sporadic transmissions. In this paper, we propose a novel contention-based multiple access scheme, named irregular repetition spatiallycoupled slotted ALOHA(IRSC-SA), motivated by the spatial coupling and irregular repetition *** are different classes of users and slots in IRSC-SA, which result in unequal protection for different users. Considering that, we derive a novel density evolution(DE) method, which deals with unequal packet protection and introduces Bayesian reasoning to analyze the throughput threshold of the proposed *** analysis and simulation results show that the proposed scheme achieves better asymptotic threshold and system packet throughput performance than the conventional spatially-coupled slotted ALOHA.

关键词： spatial coupling coded slotted ALOHA contention-based access density evolution irregular repetition

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A Coupled Approach for Fluid Dynamic Problems Using the PDE Framework Peano

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Communications in Computational Physics 2012年第6期12卷 65-84页

作者： Philipp Neumann Hans-Joachim Bungartz Miriam Mehl Tobias Neckel Tobias Weinzierl Chair of Scientific Computing Faculty of InformaticsTechnische Universitat MunchenBoltzmannstr.381545 GarchingGermany

We couple different flow models,i.e.a finite element solver for the Navier-Stokes equations and a Lattice Boltzmann automaton,using the framework Peano as a common *** new coupling strategy between the meso-and macroscopic solver is presented and validated in a 2D channel flow *** results are in good agreement with theory and results obtained in similar works by Latt et *** addition,the test scenarios show an improved stability of the coupledmethod compared to pure Lattice Boltzmann simulations.

关键词： spatial coupling Lattice Boltzmann Navier-Stokes Peano

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Optimal Scheduling of Electrical Energy Systems Using a Fluid Dynamic Analogy

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Fluid Dynamics & Materials Processing 2022年第3期18卷 577-589页

作者： Juanjuan Wang Yaya Wang Junhui Liu Jianbo Zheng Hongfang Zhou Xi’an Traffic Engineering Institute Xi’an710300China

The electricity-gas transformation problem and related intrinsic mechanisms are ***,existing schemes for the optimization of electricity-gas integrated energy systems are analyzed through consideration of the relevant literature,and an Electricity Hub(EH)for electricity-gas coupling is ***,the distribution mechanism in the circuit of the considered electricity-gas integrated system is ***,a mathematical model for the natural gas pipeline is elaborated according to the power relationship,a node power flow calculation method,and security ***,the coupling relationship between them is implemented,and dedicated simulations are carried *** experimental data,it is found that after 79 data iterations,the optimization results of power generation and gas purchase cost in the new system converge to$54,936 in total,which is consistent with the data obtained by an existing centralized optimization ***,the new proposed optimization scheme is found to be more flexible and convenient.

关键词： spatial coupling integrated energy natural gas system optimal scheduling

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空间耦合视角下的北京市可持续发展类型区划分与政策启示研究

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Journal of Geographical Sciences 2023年第12期33卷 2425-2445页

作者：王文学邓羽 Institute of Geographic Sciences and Natural Resources Research CASBeijing100101China Key Laboratory of Regional Sustainable Development Modelling CASBeijing100101China

Accurately diagnosing and assessing complicated spatial linkages at various scales has become a crucial strategy for enhancing the efficacy of urban government policies and initiatives in the modern *** is still room for improvement in identifying spatial scale disparities and coupling linkages in cities,although the standard research paradigm on urban sustainability has produced numerous positive *** advance urban sustainability research from the perspective of spatial coupling,this study used cluster and cross-tabulation analyses for considering urban sustainable development patterns from the requirements of both development scale and spatial ***,the spatial unit coupling relationship between district and street scales was *** findings indicated significant scale dependence in the spatial divergence between the built environment sustainability levels of streets and the economic,social,and environmental sustainability levels of *** implication is that significant differences exist in the built environment levels of various sustainable development type *** scale effect of the spatial coupling relationship influences urban planning and the transition of sustainable *** reasonable population density and maximizing the structure and quality of social public resources supply are priorities for streets with the highest habitat sustainability that are located in low-growth type *** should be given to population deconcentration for high habitat sustainable streets located in synergistic development type districts to increase the level of public service *** facilities should be added to medium sustainable streets in low-growth areas to increase the mix of land use,which should encourage additional production activity concentration,thereby fostering overall economic ***,increasing the accessibility of local public service facilities for low and mediu

关键词： sustainable cities development patterns spatial coupling multiscale interaction spatial structure

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