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Morphodynamics and sediment connectivity index in an unmanaged,debris-flow prone catchment:a through time perspective
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作者 Loris TORRESANI Guillaume PITON Vincenzo D’AGOSTINO 《Journal of Mountain Science》 SCIE CSCD 2023年第4期891-910,共20页
Torrential processes are among the main actors responsible for sediment production and mobility in mountain catchments.For this reason,the understanding of preferential pathways for sediment routing has become a prior... Torrential processes are among the main actors responsible for sediment production and mobility in mountain catchments.For this reason,the understanding of preferential pathways for sediment routing has become a priority in hazard assessment and mitigation.In this context,the sediment Connectivity Index(IC)enables to analyse the existing linkage between sediment sources and the selected target(channel network or catchment outlet).The IC is a grid-based index that allows fast computation of sediment connectivity based on landscape information derived from a single Digital Terrain Model(DTM).The index computation is based on the log-ratio between an upslope and a downslope component,including information about drainage area,slope,terrain roughness,and distance to the analysis target(e.g.outlet).The output is a map that highlights the degree of structural connectivity of sediment pathways over analysed catchments.Until now,these maps are however rarely used to help defining debris-flow hazard maps,notably due to a lack of guidelines to interpret the IC spatial distribution.This paper proposes an exploitation procedure along profiles to extract more information from the analysis of mapped IC values.The methodology relies on the analysis of the IC and its component variables along the main channel profile,integrated with information about sediment budgeting derived from Difference of DEMs(DoD).The study of connectivity was applied in the unmanaged sub-catchment(without torrent control works)of the Rio Soial(Autonomous Province of Trento–NE Italy)to understanding the geomorphic evolution of the area after five debris flows(in ten years)and the related changes of sediment connectivity.Using a recent DTM as validation,we demonstrated how an IC analysis over the older DTM can help predicting geomorphic changes and associated hazards.The results show an IC aptitude to capture geomorphic trajectories,anticipate debris flow deposits in a specific channel location,and depict preferential routing pathways. 展开更多
关键词 Sediment connectivity index Debris flow Hazard assessment Digital Elevation Model Geomorphic evolution DEMs of Difference
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The atom-bond connectivity index of chemical bicyclic graphs 被引量:4
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作者 CHEN Jin-song GUO Xiao-feng 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2012年第2期243-252,共10页
The atom-bond connectivity(ABC) index provides a good model for the stability of linear and branched alkanes as well as the strain energy of cycloalkanes,which is defined as ABC(G) =∑ uv∈E(G) √d u+dv-2 dudv,... The atom-bond connectivity(ABC) index provides a good model for the stability of linear and branched alkanes as well as the strain energy of cycloalkanes,which is defined as ABC(G) =∑ uv∈E(G) √d u+dv-2 dudv,where du denotes the degree of a vertex u in G.A chemical graph is a graph in which no vertex has degree greater than 4.In this paper,we obtain the sharp upper and lower bounds on ABC index of chemical bicyclic graphs. 展开更多
关键词 atom-bond connectivity index chemical bicyclic graph bound.
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Definition and Application of Topological Index Based on Bond Connectivity 被引量:1
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作者 王振东 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2003年第2期85-88,共4页
Bond connectivity topological index S i based on chemical bonds was defined by using a matrix method.And S i is formed by atomic parameters such as the number of valence electrons,the number of the highest main quan... Bond connectivity topological index S i based on chemical bonds was defined by using a matrix method.And S i is formed by atomic parameters such as the number of valence electrons,the number of the highest main quantum of atoms and the bonding electrons and bond parameters such as the length of bonds,the electronegativity difference of bonding atoms.The molecular bond connectivity topological index S is composed of S i.The thermodynamic properties of saturated hydrocarbons,unsaturated hydrocarbons,oxygen organic,methane halide and transitional element compounds and the molecular bond connectivity topological index S have an optimal correlative relationship. 展开更多
关键词 bond connectivity topological index QSPR organic system transitional elements
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On Eccentric Connectivity Index and Polynomial of Thorn Graph 被引量:1
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作者 Nilanjan De 《Applied Mathematics》 2012年第8期931-934,共4页
The eccentric connectivity index based on degree and eccentricity of the vertices of a graph is a widely used graph invariant in mathematics. In this paper we present the explicit generalized expressions for the eccen... The eccentric connectivity index based on degree and eccentricity of the vertices of a graph is a widely used graph invariant in mathematics. In this paper we present the explicit generalized expressions for the eccentric connectivity index and polynomial of the thorn graphs, and then consider some particular cases. 展开更多
关键词 Ecentricity ECCENTRic connectivity index ECCENTRic connectivity POLYNOMIAL THORN GRAPHS
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Calculation of topological connectivity index for minerals 被引量:1
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作者 曹育才 蒋玉仁 +1 位作者 薛玉兰 姜玄珍 《中国有色金属学会会刊:英文版》 CSCD 2001年第5期790-794,共5页
Topological method was applied firstly to calculate the topological connectivity index of minerals (TCIM). The reciprocal of effective atomic refractivity of metal element in minerals was chosen as its valence. The re... Topological method was applied firstly to calculate the topological connectivity index of minerals (TCIM). The reciprocal of effective atomic refractivity of metal element in minerals was chosen as its valence. The reasonability of TCIM as an activity criterion was tested through comparison of TCIM with two kinds of electronegativity parameter, i.e. ionic percentage and energy criteria of Yang’s electronegativity, solubility product, energy criterion according to the generalized perturbation theory and adsorption of flotation reagents on the surface of minerals. The results indicated that TCIM is an effective structural parameter of minerals to study the structure activity relationship. In addition, different mineral is of different TCIM value, so TCIM brings about convenience in comparison of flotation activity for minerals. 展开更多
关键词 topological connectivity index of minerals MINERALS flotation reagents
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Topological Aspects of Dendrimers via Connection-Based Descriptors 被引量:1
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作者 Muhammad Javaid Ahmed Alamer Aqsa Sattar 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第5期1649-1667,共19页
Topological indices(TIs)have been practiced for distinct wide-ranging physicochemical applications,especially used to characterize and model the chemical structures of various molecular compounds such as dendrimers,na... Topological indices(TIs)have been practiced for distinct wide-ranging physicochemical applications,especially used to characterize and model the chemical structures of various molecular compounds such as dendrimers,nanotubes and neural networks with respect to their certain properties such as solubility,chemical stability and low cytotoxicity.Dendrimers are prolonged artificially synthesized or amalgamated natural macromolecules with a sequential layer of branches enclosing a central core.A present-day trend in mathematical and computational chemistry is the characterization of molecular structure by applying topological approaches,including numerical graph invariants.Among topological descriptors,Zagreb connection indices(ZCIs)have much importance.This manuscript involves the establishment of general results to calculate ZCIs,namely first ZCI(FZCI),second ZCI(SZCI),third ZCI(TZCI),modified FZCI,modified SZCI and modified TZCI of two special types of dendrimers nanostars,namely,poly propylene imine octamin(PPIO)dendrimer and poly(propyl)ether imine(PPEtIm)dendrimer.Furthermore,we provide the numerical and graphical comparative analysis of our calculated results for both types of dendrimers with each other. 展开更多
关键词 Zagreb indices zagreb connection indices topological index dendrimer nanostars
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Quantitative Correlation between Group Connectivity Index and Property of Flotation Reagent 被引量:2
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作者 Cao, YC Jiang, YR +1 位作者 Xue, YL Wang, DZ 《Journal of Central South University》 SCIE EI CAS 2000年第1期25-28,共4页
Topological method is applied firstly to calculate the group connectivity indexes of some flotation reagents for sulfide minerals and oxide minerals. The study reveals that some properties of flotation reagents, such ... Topological method is applied firstly to calculate the group connectivity indexes of some flotation reagents for sulfide minerals and oxide minerals. The study reveals that some properties of flotation reagents, such as group electronegativity, energy criterion, solubility product of chemicals and maximum wavelength of ultraviolet absorbency, have linear correlation with the first order group connectivity index (GCI) of polar group, and the related coefficients are all larger than 0.900. The GCI can be used to characterize the structure of groups, and is a sort of new effective structural parameter to study the quantitative structure activity relationship of flotation reagents. 展开更多
关键词 FLOTATION REAGENTS group connectivity index PROPERTY QUANTITATIVE CORRELATION
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An Adaptive Parameter-Free Optimal Number of Market Segments Estimation Algorithm Based on a New Internal Validity Index
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作者 Jianfang Qi Yue Li +3 位作者 Haibin Jin Jianying Feng Dong Tian Weisong Mu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第10期197-232,共36页
An appropriate optimal number of market segments(ONS)estimation is essential for an enterprise to achieve successful market segmentation,but at present,there is a serious lack of attention to this issue in market segm... An appropriate optimal number of market segments(ONS)estimation is essential for an enterprise to achieve successful market segmentation,but at present,there is a serious lack of attention to this issue in market segmentation.In our study,an independent adaptive ONS estimation method BWCON-NSDK-means++is proposed by integrating a newinternal validity index(IVI)Between-Within-Connectivity(BWCON)and a newstable clustering algorithmNatural-SDK-means++(NSDK-means++)in a novel way.First,to complete the evaluation dimensions of the existing IVIs,we designed a connectivity formula based on the neighbor relationship and proposed the BWCON by integrating the connectivity with other two commonly considered measures of compactness and separation.Then,considering the stability,number of parameters and clustering performance,we proposed the NSDK-means++to participate in the integrationwhere the natural neighbor was used to optimize the initial cluster centers(ICCs)determination strategy in the SDK-means++.At last,to ensure the objectivity of the estimatedONS,we designed a BWCON-based ONS estimation framework that does not require the user to set any parameters in advance and integrated the NSDK-means++into this framework forming a practical ONS estimation tool BWCON-NSDK-means++.The final experimental results showthat the proposed BWCONand NSDK-means++are significantlymore suitable than their respective existing models to participate in the integration for determining theONS,and the proposed BWCON-NSDK-means++is demonstrably superior to the BWCON-KMA,BWCONMBK,BWCON-KM++,BWCON-RKM++,BWCON-SDKM++,BWCON-Single linkage,BWCON-Complete linkage,BWCON-Average linkage and BWCON-Ward linkage in terms of the ONS estimation.Moreover,as an independentmarket segmentation tool,the BWCON-NSDK-means++also outperforms the existing models with respect to the inter-market differentiation and sub-market size. 展开更多
关键词 Optimal number of market segments internal validity index cluster connectivity SDK-means++ market segmentation
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Impact of Using Stevia on Physicochemical, Sensory, Rheology and Glycemic Index of Soft Ice Cream 被引量:1
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作者 Mohammad Alizadeh Maryam Azizi-Lalabadi Sorayya Kheirouri 《Food and Nutrition Sciences》 2014年第4期390-396,共7页
The aim of this study was to formulate and develop a low calorie and low glycemic index (GI) of soft ice cream by using mixture of sucrose and Stevia. Five different formulations of ice cream were produced by using di... The aim of this study was to formulate and develop a low calorie and low glycemic index (GI) of soft ice cream by using mixture of sucrose and Stevia. Five different formulations of ice cream were produced by using different proportions of sucrose and Stevia. Physicochemical characteristics, hedonic sensory evaluations and glycemic index determination of products were carried out by following conventional methods. Replacement of sucrose with Stevia resulted in a significantly lower viscosity and brix with a higher overrun and melting rate in a dose dependent manner. Total replacing of sucrose with Stevia resulted in significant reduction in caloric value from 143.03 to 105.25 Kcal and GI from 79.06 ± 4.0 to 72.18 ± 5.27 as compared to those of sucrose based formulation (p 0.05) indicating a 37.78% and 6.88% reduction, respectively. TB had the best sensory acceptance among all the treatments. We concluded that substitution of sucrose with Stevia may be a choice to produce low caloric and GI ice creams. However, using mixture of the two sweeteners improves sensory acceptance of the formulations. 展开更多
关键词 Glycemic index STEVIA ice CREAM OVERRUN Melting Rate
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On the maximal eccentric connectivity indices of graphs
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作者 ZHANG Jian-bin LIU Zhong-zhu ZHOU Bo 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2014年第3期374-378,F0003,共6页
For a connected simple graph G, the eccentricity ec(v) of a vertex v in G is the distance from v to a vertex farthest from v, and d(v) denotes the degree of a vertex v. The eccentric connectivity index of G, denot... For a connected simple graph G, the eccentricity ec(v) of a vertex v in G is the distance from v to a vertex farthest from v, and d(v) denotes the degree of a vertex v. The eccentric connectivity index of G, denoted by ξC(G), is defined as ∑vЕV(G) d(v)ec(v). In this paper, we will determine the graphs with maximal eccentric connectivity index among the connected graphs with n vertices and m edges(n ≤ m ≤ n + 4), and propose a conjecture on the graphs with maximal eccentric connectivity index and m edges (m ≥ n + 5). among the connected graphs with n vertices 展开更多
关键词 Eccentric connectivity index DIAMETER DISTANCE
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Study on Landscape Pattern Index-based Connectivity Analysis of the Primary Farmland Protection Zones
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作者 MENG Dandan ZHANG Jinping +1 位作者 ZHANG Baohua PAN Qinglong 《Journal of Landscape Research》 2015年第1期9-10,12,共3页
Farmland and primary farmland protection are important contents of land management and land use planning of China. In the new round of land use planning and database construction, primary farmland protection zones are... Farmland and primary farmland protection are important contents of land management and land use planning of China. In the new round of land use planning and database construction, primary farmland protection zones are required to have high integrity and connectivity. Using landscape pattern indexes, the integrity and connectivity of primary farmland protection zones was studied in Licheng District of Jinan City. The results showed that, except patch area standard deviation, the other indexes including average patch area, patch area variation coefficient, patch edge density, largest patch index, and mean euclidean nearest-neighbor, all indicate high connectivity of primary farmland protection zones after layout adjustment. A simple and convenient method for identifying the integrity and connectivity of primary farmland protection zones was supplied. 展开更多
关键词 Primary farmland protection zone Integrity and connectivity Landscape pattern index
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波兰《哥白尼索引》(Index of Copurnicus,IC)简介
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《国际眼科杂志》 CAS 2009年第2期245-245,共1页
关键词 哥白尼 波兰 index of Copurnicus ic 索引 通检 检索工具
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ANALYSIS OF SOUTHEAST ASIAN NATIONS FIVE CONNECTIVITY INDEX
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作者 Chen Yiyuan 《China Report ASEAN》 2019年第6期60-63,共4页
Located at the crossroads to Belt and Road connecting the continent and the sea, Southeast Asian countries are at the junction of some of the world’s most important sea routes. As the first countries to rally around ... Located at the crossroads to Belt and Road connecting the continent and the sea, Southeast Asian countries are at the junction of some of the world’s most important sea routes. As the first countries to rally around the 21st Century Maritime Silk Road Initiative, Southeast Asian countries have been key partners and top priorities in construction of the Belt and Road promoted by China. After years of steady progress, China and Southeast Asian countries have secured great achievements in Belt and Road construction to enhance connectivity. According to a census conducted by a subject group, the overall performance of Southeast Asian countries ranked first compared to the other regions along the Belt and Road in 2017. Some countries in ASEAN region are seeing major improvements. 展开更多
关键词 ANALYSIS ASIAN NATIONS connectivity index
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Wiener Index, Hyper-Wiener Index, Harary Index and Hamiltonicity Properties of graphs
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作者 YU Gui-dong REN Li-fang LI Xing-xing 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2019年第2期162-172,共11页
In this paper, in terms of Wiener index, hyper-Wiener index and Harary index, we first give some sufficient conditions for a nearly balance bipartite graph with given minimum degree to be traceable. Secondly, we estab... In this paper, in terms of Wiener index, hyper-Wiener index and Harary index, we first give some sufficient conditions for a nearly balance bipartite graph with given minimum degree to be traceable. Secondly, we establish some conditions for a k-connected graph to be Hamilton-connected and traceable for every vertex, respectively. 展开更多
关键词 WIENER index Hyper-Wiener index Harary index TRACEABLE HAMILTON-CONNECTED TRACEABLE for EVERY vertex
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The First Eccentric Zagreb Index of Linear Polycene Parallelogram of Benzenoid
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作者 Mehdi Alaeiyan Mohammad Reza Farahani +1 位作者 Muhammad Kamran Jamil M. R. Rajesh Kanna 《Open Journal of Applied Sciences》 2016年第5期315-318,共4页
Let G = (V,E) be a graph, where V(G) is a non-empty set of vertices and E(G) is a set of edges, e = uv∈E(G), d(u) is degree of vertex u. Then the first Zagreb polynomial and the first Zagreb index Zg<sub>1</... Let G = (V,E) be a graph, where V(G) is a non-empty set of vertices and E(G) is a set of edges, e = uv∈E(G), d(u) is degree of vertex u. Then the first Zagreb polynomial and the first Zagreb index Zg<sub>1</sub>(G,x) and Zg<sub>1</sub>(G) of the graph G are defined as Σ<sub>uv∈E(G)</sub>x<sup>(d<sub>u</sub>+d<sub>v</sub>)</sup> and Σ<sub>e=uv∈E(G)</sub>(d<sub>u</sub>+d<sub>v</sub>) respectively. Recently Ghorbani and Hosseinzadeh introduced the first Eccentric Zagreb index as Zg<sub>1</sub>*</sup>=Σ<sub>uv∈E(G)</sub>(ecc(v)+ecc(u)), that ecc(u) is the largest distance between u and any other vertex v of G. In this paper, we compute this new index (the first Eccentric Zagreb index or third Zagreb index) of an infinite family of linear Polycene parallelogram of benzenoid. 展开更多
关键词 Molecular Graph Linear Polycene Parallelogram of Benzenoid Zagreb Topological index Eccentricity connectivity index Cut Method
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Definition of Arctic and Antarctic Sea Ice Variation Index
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作者 陈红霞 刘娜 +1 位作者 潘增弟 张庆华 《Chinese Journal of Polar Science》 2004年第2期137-142,共6页
It is well known that varying of the sea ice not only in the Antarctic but also in the Arctic has an active influence on the globe atmosphere and ocean. In order to understand the sea ice variation in detail, for the ... It is well known that varying of the sea ice not only in the Antarctic but also in the Arctic has an active influence on the globe atmosphere and ocean. In order to understand the sea ice variation in detail, for the first time, an objective index of the Arctic and Antarctic sea ice variation is defined by projecting the monthly sea ice concentration anomalies poleward of 20°N or 20°S onto the EOF (empirical orthogonal function)-1 spatial pattern. Comparing with some work in former studies of polar sea ice, the index has the potential for clarifying the variability of sea ice in northern and southern high latitudes. 展开更多
关键词 Arctic sea ice Antarctic sea ice variation index.
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A multi-index coupling system of ice slope stability and its application
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作者 WanSheng Pei YuanMing Lai +2 位作者 MingYi Zhang HongYu Xu Wu Chen 《Research in Cold and Arid Regions》 2012年第3期185-194,共10页
Based on the Simplified Bishop Method, the minimum safety factor of ice slope both with and without tension cracks is calculated in combination with triaxial compression tests. It is found that there exists a critical... Based on the Simplified Bishop Method, the minimum safety factor of ice slope both with and without tension cracks is calculated in combination with triaxial compression tests. It is found that there exists a critical depth for each crack. Then, factors influencing ice slope stability such as slope ratio, slope height, ice cohesion, internal friction angle, unit weight and temperature were analyzed. Meanwhile, a regression equation between the aforementioned factors and safety factor is obtained, with which sensitivity analysis is carried out. The performance function is built in combination with random distribution of physical and mechanical parameters to analyze the reliability index. The Advanced First Order Second Moment Method is employed on the solution to the perfor- mance function. The one-way coupling system of ice slope stability is therefore formed based on safety factor and reliability index. Finally, an illustrated example of ice slope is provided, which shows that failure probability is relatively high, up to 6.18%, alt- hough safety factor is 2.77. Thus, it is objective and reasonable to apply the coupled system method to the slope stability rating. 展开更多
关键词 ice slope stability safety factor sensitivity analysis reliability index Advanced First Order Second Moment Method
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Spatial connectivity and distribution of landscape type in the natural secondary forests of eastern mountainous region,northeast China——a case study of Mao'ershan region in Heilongjiang Province
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作者 李淑娟 隋玉正 +2 位作者 冯海清 王凤友 李玉文 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第2期141-144,i003,共5页
Mao'ershan region is representative in the natural secondary forested region of the eastern mountainous region, northeast China. The landscape nearest neighbor index and landscape connectivity index were calculate... Mao'ershan region is representative in the natural secondary forested region of the eastern mountainous region, northeast China. The landscape nearest neighbor index and landscape connectivity index were calculated with ARC/INFO software for Mao'ershan region. The spatial distribution of the landscape of the region was analyzed. The results showed that the landscape connectivity index of non-woodland was significantly higher than that of woodland. The landscape connectivity index of natural forest was nearly equal to zero, which means its fragmentation degree is high. The nearest neighbor index of plantation was lower than that of natural forest and non-forestland. Among the man-made forests, the distance index of the coniferous mixed plantation is the lowest, and its pattern is nearly glomeration. The landscape pattern of natural forest presented nearly random distribution. Among non-forest land, the distance index of cut blank was the lowest, and its pattern was also nearly glomeration. Keywords Landscape type - Landscape pattern - Nearest neighbor index - Landscape connectivity index - Natural secondary forest - Northeast China CLC number S759.92 Document code A Foundation item: This paper was supported by the Key Project of State Department of Science Technology (2002BA515B040).Biography: LI SHu-juan (1977), female. Lecture in Ocean University of China, Qingdao 266003, P. R. China.Responsible editor: Zhu Hong 展开更多
关键词 Landscape type Landscape pattern Nearest neighbor index Landscape connectivity index Natural secondary forest Northeast China
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THEORETICAL MODEL OF EFFECTIVE STRESS COEFFICIENT FOR ROCK/SOIL-LIKE POROUS MATERIALS 被引量:5
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作者 Kai Zhang Hui Zhou Dawei Hu Yang Zhao Xiating Feng 《Acta Mechanica Solida Sinica》 SCIE EI 2009年第3期251-260,共10页
Physical mechanisms and influencing factors on the effective stress coefficient for rock/soil-like porous materials are investigated, based on which equivalent connectivity index is proposed. The equivalent connectivi... Physical mechanisms and influencing factors on the effective stress coefficient for rock/soil-like porous materials are investigated, based on which equivalent connectivity index is proposed. The equivalent connectivity index, relying on the meso-scale structure of porous material and the property of liquid, denotes the connectivity of pores in Representative Element Area (REA). If the conductivity of the porous material is anisotropic, the equivalent connectivity index is a second order tensor. Based on the basic theories of continuous mechanics and tensor analysis, relationship between area porosity and volumetric porosity of porous materials is deduced. Then a generalized expression, describing the relation between effective stress coefficient tensor and equivalent connectivity tensor of pores, is proposed, and the expression can be applied to isotropic media and also to anisotropic materials. Furthermore, evolution of porosity and equivalent connectivity index of the pore are studied in the strain space, and the method to determine the corresponding functions in expressions above is proposed using genetic algorithm and genetic programming. Two applications show that the results obtained by the method in this paper perfectly agree with the test data. This paper provides an important theoretical support to the coupled hydro-mechanical research. 展开更多
关键词 rock/soil-like porous materials generalized model for effective stress coefficient tensor equivalent connectivity index of pore genetic algorithm
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基于连通性指数(IC)的近30年鄱阳湖流域水系结构与水文连通演变评估 被引量:2
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作者 曾冰茹 李云良 谭志强 《湖泊科学》 EI CAS CSCD 北大核心 2023年第5期1796-1807,共12页
由于气候变化和人类活动等多重影响,流域河湖水系格局与连通程度发生了显著变化,进而引发洪涝灾害等一系列水资源问题。本文以鄱阳湖流域为研究区,基于Google Earth Engine(GEE)提取1989—2020年5期水系数据,采用图论方法构建水系评价体... 由于气候变化和人类活动等多重影响,流域河湖水系格局与连通程度发生了显著变化,进而引发洪涝灾害等一系列水资源问题。本文以鄱阳湖流域为研究区,基于Google Earth Engine(GEE)提取1989—2020年5期水系数据,采用图论方法构建水系评价体系,定量分析该地区近30年来水系格局和结构连通性的时空演变特征,并结合该时期地形、土地利用和归一化植被指数(NDVI)等数据,利用连通性指数(index of connectivity,IC)评估功能连通性的动态变化,进而探讨水文连通与径流量和输沙量的联系。结果表明,近30年来鄱阳湖流域水系结构趋于复杂化,主要体现在流域北部。除干流外,其他等级河流的数量和长度均有所增加,其中Ⅲ级河流最为明显。河网密度、水面率、河网复杂度和发育系数均呈增加趋势,2000年后的变化率约为2000年前的两倍。水系连通环度、节点连接率和水系连通度总体增加,结构连通性呈好转趋势且变化幅度较小。功能连通分析表明,近30年来大部分流域IC减少,流域下游靠近主河道的平坦地区IC较高,上游远离河道的植被密集区域IC较低。此外,IC与年径流量和输沙量表现为显著的正相关性(相关系数分别为0.6和0.7)。总体而言,随着鄱阳湖流域水利工程建设的增加以及土地利用的变化,水系结构变化显著,结构连通性呈增长趋势,而表示径流泥沙的功能连通性在2000年后逐渐减小。本文基于流域结构和功能连通的视角,开展连通性评价指标的时空变化研究,可显著提升对新时期鄱阳湖流域水系连通演变及水土资源保护的理解与认识。 展开更多
关键词 水系结构 ic指数 水文连通 鄱阳湖流域 径流泥沙
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