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AIGCrank:A new adaptive algorithm for identifying a set of influential spreaders in complex networks based on gravity centrality
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作者 杨平乐 赵来军 +2 位作者 董晨 徐桂琼 周立欣 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第5期724-736,共13页
The influence maximization problem in complex networks asks to identify a given size of seed spreaders set to maximize the number of expected influenced nodes at the end of the spreading process.This problem finds man... The influence maximization problem in complex networks asks to identify a given size of seed spreaders set to maximize the number of expected influenced nodes at the end of the spreading process.This problem finds many practical applications in numerous areas such as information dissemination,epidemic immunity,and viral marketing.However,most existing influence maximization algorithms are limited by the“rich-club”phenomenon and are thus unable to avoid the influence overlap of seed spreaders.This work proposes a novel adaptive algorithm based on a new gravity centrality and a recursive ranking strategy,named AIGCrank,to identify a set of influential seeds.Specifically,the gravity centrality jointly employs the neighborhood,network location and topological structure information of nodes to evaluate each node's potential of being selected as a seed.We also present a recursive ranking strategy for identifying seed nodes one-byone.Experimental results show that our algorithm competes very favorably with the state-of-the-art algorithms in terms of influence propagation and coverage redundancy of the seed set. 展开更多
关键词 influential nodes influence maximization gravity centrality recursive ranking strategy
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Spatial and temporal patterns of the inter-annual oscillations of glacier mass over Central Asia inferred from Gravity Recovery and Climate Experiment(GRACE) data 被引量:2
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作者 ZHU Chuandong LU Yang +1 位作者 SHI Hongling ZHANG Zizhan 《Journal of Arid Land》 SCIE CSCD 2017年第1期87-97,共11页
Monitoring glacier mass balance is crucial to managing water resources and also to understanding climate change for the arid and semi-arid regions of Central Asia. This study extracted the inter-annual oscillations of... Monitoring glacier mass balance is crucial to managing water resources and also to understanding climate change for the arid and semi-arid regions of Central Asia. This study extracted the inter-annual oscillations of glacier mass over Central Asia from the first ten principal components(S-PCs) of filtered variability via multichannel singular spectral analysis(MSSA), based on gridded data of glacier mass inferred from Gravity Recovery and Climate Experiment(GRACE) data obtained from July 2002 to March 2015. Two significant cycles of glacier mass balance oscillations were identified. The first cycle with a period of 6.1-year accounted for 54.5% of the total variance and the second with a period of 2.3-year accounted for 4.3%. The 6.1-year oscillation exhibited a stronger variability compared with the 2.3-year oscillation. For the 6.1-year oscillation, the results from lagged cross-correlation function suggested that there were significant correlations between glacier mass balances and precipitation variations with the precipitation variations leading the response of glacier mass balances by 9–16 months. 展开更多
关键词 gravity Recovery and Climate Experiment glacier mass balance multichannel singular spectral analysis central Asia
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Evidence for the Upwelling of Mafic Bodies into the Upper Crust beneath the N40-50&#176;E Branch of the Pan-African Central Cameroon Shear Zone from Gravity Studies 被引量:1
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作者 Loudi Yap Robert Nouayou +2 位作者 Depesquidoux Tchaptchet Tchato Joseph Kamguia Apollinaire Bouba 《Open Journal of Geology》 2018年第3期278-297,共20页
The existence of mafic bodies at mid crustal level beneath the Pan-African Central Cameroon Shear Zone is still a matter of debate. To provide additional constrains on this issue, the crust of the west region of Camer... The existence of mafic bodies at mid crustal level beneath the Pan-African Central Cameroon Shear Zone is still a matter of debate. To provide additional constrains on this issue, the crust of the west region of Cameroon has been investigated using gravity data. Analyses of these data show N40-50&#176;E oriented iso-anomal contours in the Bafoussam area, interpreted as the N40-50&#176;E branch of the Central Cameroon Shear Zone. In addition, spectral analysis and 2.5D gravity modeling reveal intrusions of mafic bodies at depth between 3.2 and 14.2 km under N40-50&#176;E aligned volcanic centers, namely Mt Bambouto and Mt Mbapit. The above observations suggest a structurally controlled emplacement of the mafic bodies. In the light of the recent geophysical data, the interaction between the NE-ward channel flow operating at the bottom of the lithosphere or the asthenosphere upwelling and the Cameroon Shear Zone could better explain the magma upwelling in the upper crust. This result is the novelty of the present work. 展开更多
关键词 West Region MAFIC BODIES central Cameroon Shear Zone gravity 2.5D Modelling
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Features of isostatic gravity anomaly and seismic activity in the Central Asian region
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作者 方盛明 冯锐 +3 位作者 田长征 孙桂香 王志理 李长法 《Acta Seismologica Sinica(English Edition)》 CSCD 1997年第6期105-109,共5页
In this paper, the lithospheric isostatic gravity anomaly with its distribution features in the Central Asian region (30°~70°N, 50°~140°E), according to the research of the lithospheric isostati... In this paper, the lithospheric isostatic gravity anomaly with its distribution features in the Central Asian region (30°~70°N, 50°~140°E), according to the research of the lithospheric isostatic principle, is discussed. Moreover, some primary structures and seismic activities in this region are discussed. 展开更多
关键词 isostatic gravity anomaly regional structure seismic activity the central Asian region
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Six-Element Yagi Array Designs Using Central Force Optimization with Pseudo Random Negative Gravity 被引量:1
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作者 Richard A. Formato 《Wireless Engineering and Technology》 2021年第3期23-51,共29页
A six-element Yagi-Uda array is optimally designed using Central Force Optimization (CFO) with a small amount of pseudo randomly injected negative gravity. CFO is a simple, deterministic metaheuristic analogizing grav... A six-element Yagi-Uda array is optimally designed using Central Force Optimization (CFO) with a small amount of pseudo randomly injected negative gravity. CFO is a simple, deterministic metaheuristic analogizing gravitational kinematics (motion of masses under the influence of gravity). It has been very effective in addressing a wide range of antenna and other problems and normally employs only positive gravity. With positive gravity the six element CFO-designed Yagi array described here exhibits excellent performance with respect to the objectives of impedance bandwidth and forward gain. This paper addresses the question of what happens when a small amount of negative gravity is injected into the CFO algorithm. Does doing so have any effect, beneficial, negative or neutral? In this particular case negative gravity improves CFO’s exploration and creates a region of optimality containing many designs that perform about as well as or better than the array discovered with only positive gravity. Without some negative gravity these array configurations are overlooked. This Yagi-Uda array design example suggests that antennas optimized or designed using deterministic CFO may well benefit by including a small amount of negative gravity, and that the negative gravity approach merits further study. 展开更多
关键词 ANTENNA 6-Element Array Yagi Yagi-Uda ARRAY Impedance Bandwidth VSWR Forward Gain Antenna Design Antenna Optimization central Force Optimization CFO Deterministic Metaheuristic Evolutionary Algorithm gravity Gravitational Kinematics Exploration Exploitation
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Central Force Optimization with Gravity <0, Elitism, and Dynamic Threshold Optimization: An Antenna Application, 6-Element Yagi-Uda Arrays
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作者 Richard A. Formato 《Wireless Engineering and Technology》 2021年第4期53-82,共30页
This paper investigates the effect of adding three extensions to Central Force Optimization when it is used as the Global Search and Optimization method for the design and optimization of 6-elementYagi-Uda arrays. Tho... This paper investigates the effect of adding three extensions to Central Force Optimization when it is used as the Global Search and Optimization method for the design and optimization of 6-elementYagi-Uda arrays. Those exten</span><span><span style="font-family:Verdana;">sions are </span><i><span style="font-family:Verdana;">Negative</span></i> <i><span style="font-family:Verdana;">Gravity</span></i><span style="font-family:Verdana;">, </span><i><span style="font-family:Verdana;">Elitism</span></i><span style="font-family:Verdana;">, and </span><i><span style="font-family:Verdana;">Dynamic</span></i> <i><span style="font-family:Verdana;">Threshold</span></i> <i><span style="font-family:Verdana;">Optimization</span></i><span style="font-family:Verdana;">. T</span></span><span style="font-family:Verdana;">he basic CFO heuristic does not include any of these, but adding them substan</span><span style="font-family:Verdana;">tially improves the algorithm’s performance. This paper extends the work r</span><span style="font-family:Verdana;">eported in a previous paper that considered only negative gravity and which </span><span style="font-family:Verdana;">showed a significant performance improvement over a range of optimized a</span><span style="font-family:Verdana;">rrays. Still better results are obtained by adding to the mix </span><i><span style="font-family:Verdana;">Elitism</span></i><span style="font-family:Verdana;"> and </span><i><span style="font-family:Verdana;">DTO</span></i><span style="font-family:Verdana;">. An overall improvement in best fitness of 19.16% is achieved by doing so. While the work reported here was limited to the design/optimization of 6-</span></span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">element Yagis, the reasonable inference based on these data is that any antenna design/optimization problem, indeed any Global Search and Optimiza</span><span style="font-family:Verdana;">tion problem, antenna or not, utilizing Central Force Optimization as the Gl</span><span style="font-family:Verdana;">obal Search and Optimization engine will benefit by including all three extensions, probably substantially. 展开更多
关键词 Yagi Yagi-Uda Array ANTENNA Antenna Design OPTIMIZATION central Force central Force Optimization CFO CFO-GED Negative gravity ELITISM Dynamic Threshold Optimization DTO Dynamic Threshold Metaheuristic Evolutionary Computation
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基于拉普拉斯引力中心性的时效网络关键节点辨识
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作者 詹凤 周传华 周家亿 《武汉理工大学学报(信息与管理工程版)》 2026年第1期97-102,共6页
时效网络关键节点是在动态演化的网络结构中制约网络动力学行为效果和范围的时空枢纽,精准辨识该类节点是理解、预测和控制网络动力学行为的基础和前提。现有的基于局部性的辨识方法主要对节点的邻域结构关系进行显式建模,对节点之间隐... 时效网络关键节点是在动态演化的网络结构中制约网络动力学行为效果和范围的时空枢纽,精准辨识该类节点是理解、预测和控制网络动力学行为的基础和前提。现有的基于局部性的辨识方法主要对节点的邻域结构关系进行显式建模,对节点之间隐含的时序影响关系描述不足。因此,提出一种基于拉普拉斯引力中心性的时效网络关键节点辨识方法,引入拉普拉斯中心性重构引力模型,突出表达邻域范围内节点之间的时序吸引关系,对节点的重要性进行更细粒度的区分。基于真实网络数据集开展仿真实验,结果表明该方法在肯德尔相关系数上优于对比方法,是识别关键节点的有效手段。 展开更多
关键词 复杂网络 关键节点 引力模型 时效网络 拉普拉斯中心性
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货币数字化对中国跨境商品贸易潜力及效率的影响
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作者 林晓伟 林静 《兰州交通大学学报》 2026年第1期106-117,共12页
央行数字货币作为法定货币的数字化形态,其发展为跨境商品贸易创造了新机遇。采用2014—2022年我国与54个国家双边贸易的面板数据,构建随机前沿引力模型,测算双边商品贸易效率,并考察贸易国央行数字货币发展对我国跨境商品贸易的影响。... 央行数字货币作为法定货币的数字化形态,其发展为跨境商品贸易创造了新机遇。采用2014—2022年我国与54个国家双边贸易的面板数据,构建随机前沿引力模型,测算双边商品贸易效率,并考察贸易国央行数字货币发展对我国跨境商品贸易的影响。研究发现:我国双边商品贸易效率整体较低,且各国贸易效率差异较大,具有充足的潜力空间;贸易国央行数字货币发展对我国跨境商品贸易影响显著,这一结论在更换核心解释变量、剔除部分样本、检验互为因果问题后依旧成立;且贸易国央行数字货币发展对我国商品进口贸易、与发展中国家跨境商贸的影响更为显著;贸易国央行数字货币可降低贸易成本,促进我国跨境商贸发展。因此,应基于CIPS系统建设多边央行数字货币跨境支付网络;依据贸易国央行数字货币的发展阶段采取差异化策略,深化同发展中国家的双边合作,推动我国跨境商品贸易高质量发展。 展开更多
关键词 央行数字货币(CBDC) 贸易效率 随机前沿引力模型
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A Comparative Study of Methods for Delineating Sphere of Urban Influence: A Case Study on Central China 被引量:6
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作者 WANG Hao DENG Yu +1 位作者 TIAN Enze WANG Kaiyong 《Chinese Geographical Science》 SCIE CSCD 2014年第6期751-762,共12页
A number of urban and regional plans have been developed with the advancement of urbanization and regional integration, among which the delineation of sphere of urban influence and improvement of integration between t... A number of urban and regional plans have been developed with the advancement of urbanization and regional integration, among which the delineation of sphere of urban influence and improvement of integration between the city and its hinterland have be- come vital important for guiding practices. In terms of delineating sphere of urban influence, existing studies have been focused on static study by using single year data or single method, resulting in a lack of time-series longitudinal analysis or comprehensive analysis based on multiple methods This study emphasizes on comparing two methods from both the theoretical and empirical perspective. Both gravity model and improwd field model are applied to the selected study area for measurements and comparison, to explore their strengths and weaknesses. A research framework for comprehensive analysis on delineating sphere of urban influence is proposed. In the end, the differences of deli:aeating methods are illustrated and the feasibility of comprehensive analysis is discussed. Recommendations are provided for selecting appropriate methods for delineating sphere of urban influence or developing regional hierarchy system plans and urban spatial structure schemes. 展开更多
关键词 gravity model improved field model sphere of urban influence regional planning central China
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Structural characteristics of the KPR-CBR triple-junction inferred from gravity and magnetic interpretations,Philippine Sea Plate 被引量:4
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作者 Lu-ning Shang Pan-feng Li +9 位作者 Run-lin Du Feng-long Bai Gang Hu Wen-chao Lü Xia Li Xi Mei Tian-yu Zhang Hou-zhen Cao Jing-yi Cong Xian-yao Shi 《China Geology》 2021年第4期541-552,共12页
The intersection of the Kyushu-Palau Ridge(KPR)and the Central Basin Rift(CBR)of the West Philippine Basin(WPB)is a relic of a trench-trench-rift(TTR)type triple-junction,which preserves some pivotal information on th... The intersection of the Kyushu-Palau Ridge(KPR)and the Central Basin Rift(CBR)of the West Philippine Basin(WPB)is a relic of a trench-trench-rift(TTR)type triple-junction,which preserves some pivotal information on the cessation of the seafloor spreading of the WPB,the emplacement and disintegration of the proto-Izu-Bonin-Mariana(IBM)Arc,and the transition from initial rifting to steady-state spreading of the Parece Vela Basin(PVB).However,the structural characteristics of this triple-junction have not been thoroughly understood.In this paper,using the newly acquired multi-beam bathymetric,gravity,and magnetic data obtained by the Qingdao Institute of Marine Geology,China Geological Survey,the authors depict the topographic,gravity,and magnetic characteristics of the triple-junction and adjacent region.Calculations including the upward continuations and total horizontal derivatives of gravity anomaly are also performed to highlight the major structural features and discontinuities.Based on these works,the morphological and structural features and their formation mechanisms are analyzed.The results show that the last episode amagmatic extension along the CBR led to the formation of a deep rift valley,which extends eastward and incised the KPR.The morphological and structural fabrics of the KPR near and to the south of the triple-junction are consistent with those of the western PVB,manifesting as a series of NNE-SSW-and N-S-trending ridges and troughs,which were produced by the extensional faults associated with the initial rifting of the PVB.The superposition of the above two reasons induced the prominent discontinuity of the KPR in deep and shallow crustal structures between 15°N‒15°30′N and 13°30′N‒14°N.Combined with previous authors’results,we propose that the stress produced by the early spreading of the PVB transmitted westward and promoted the final stage amagmatic extension of the CBR.The eastward propagation of the CBR destroyed the KPR,of which the magmatism had decayed or ceased at that time.The destruction mechanism of the KPR associated with the rifting of the PVB varies along strike the KPR.Adjacent to the triple-junction,the KPR was destroyed mainly due to the oblique intersection of the PVB rifting center.Whereas south of the triple-junction,the KPR was destroyed by the E-W-directional extensional faulting on its whole width. 展开更多
关键词 Kyushu-Palau Ridge central Basin Rift Tecto-morphological features gravity and magnetic anomalies Back-arc spreading Structural discontinuities Philippine Sea Plate Marine scientific survey
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Assessing Spatio-temporal Characteristics of Water Storage Changes in the Mountainous Areas of Central Asia Based on GRACE 被引量:1
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作者 ZHANG Pengfei CHEN Xi +2 位作者 BAO Anming LIU Tie Felix NDAYISABA 《Chinese Geographical Science》 SCIE CSCD 2017年第6期918-933,共16页
The mountainous areas of Central Asia provide substantial water resources, and studying change in water storage and the impacts of precipitation and snow cover in the mountain ranges of Central Asia is of the greatest... The mountainous areas of Central Asia provide substantial water resources, and studying change in water storage and the impacts of precipitation and snow cover in the mountain ranges of Central Asia is of the greatest importance for understanding regional water shortages and the main factors. Data from the GRACE (Gravity Recovery and Climate Experiment) satellites, precipitation prod- ucts and snow-covered area data were used to analyze the spatio-temporal characteristics of water storage changes and the effects of precipitation and snow cover from April 2002 to December 2013. The results were computed for each mountain ranges, and the follow- ing conclusions were drawn. The water storage in the mountainous areas of Central Asia as a whole increases in summer and winter, whereas it decreases in autumn. The water storage is affected by precipitation to some extent and some areas exhibit hysteresis. The area of positive water storage changes moves from west to east over the course of the year. The water storage declined during the period 2002-2004. It then returned to a higher level in 2005-2006 and featured lower levels in 2007-009 Subsequently, the water storage increased gradually from 2010 to 2013. The Eastern Tianshan Mountains and Western Tianshan Mountain subzones examined in this study display similar tendencies, and the trends observed in the Karakorum Mountains and the Kunlun Mountains are also similar. However, the Eastern Tianshan Mountains and Western Tianshan Mountains were influenced by precipitation to a greater degree than the latter two ranges. The water storage in Qilian Mountains showed a pronounced increasing trend, and this range is the most strongly affected by precipitation. Based on an analysis of all investigated subzones, precipitation has the greatest influence on total water storage relative to the snow covered area in some areas of Central Asia. The results obtained from this study will be of value for scientists stud- ying the mechanisms that influence changes in water storage in Central Asia. 展开更多
关键词 water storage gravity Recovery and Climate Experiment (GRACE) mountainous areas central Asia PRECIPITATION
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A special fermionic generalization of lineal gravity
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作者 DUPLIJ S. A. SOROKA D. V. SOROKA V. A. 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第4期629-632,共4页
The central extension of the (1+1)-dimensional Poincaré algebra by including fermionic charges which obey not supersymmetric algebra, but a special graded algebra containing in the right hand side a central eleme... The central extension of the (1+1)-dimensional Poincaré algebra by including fermionic charges which obey not supersymmetric algebra, but a special graded algebra containing in the right hand side a central element only is obtained. The corresponding theory being the fermionic extension of the lineal gravity is proposed. We considered the algebra of generators, the field transformations and found Lagrangian and equation of motion, then we derived the Casimir operator and obtained the con- stant black hole mass. 展开更多
关键词 Black hole central extension Lineal gravity Fermionic generator Casimir operator
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Structural features in the mid-southern section of the Kyushu–Palau Ridge based on satellite altimetry gravity anomaly
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作者 Feifei Zhang Dingding Wang +3 位作者 Xiaolin Ji Fanghui Hou Yuan Yang Wanyin Wang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第4期50-60,共11页
The Kyushu–Palau Ridge(KPR),an anti-S-shaped submarine highland at the center of the Philippine Sea Plate(PSP),is considered the residual arc of the Izu–Bonin–Mariana Island Arc,which retains key information about ... The Kyushu–Palau Ridge(KPR),an anti-S-shaped submarine highland at the center of the Philippine Sea Plate(PSP),is considered the residual arc of the Izu–Bonin–Mariana Island Arc,which retains key information about the cessation of the Western Philippine Basin(WPB)expansion and the Parece Vela Basin(PVB)breakup.Herein,using the new generation of satellite altimetry gravity data,high-precision seafloor topography data,and newly acquired ship-borne gravity data,the topographic and gravity characteristics of the KPR mid-southern section and adjacent region are depicted.The distribution characteristics of the faults were delineated using the normalized vertical derivative–total horizontal derivative method(NVDR-THDR)and the minimum curvature potential field separation method.The Moho depth and crustal thickness were inverted using the rapid inversion method for a double-interface model with depth constraints.Based on these results,the crust structure features in the KPR mid-southern section,and the“triangular”structure geological significance where the KPR and Central Basin Rift(CBR)of the WPB intersect are interpreted.The KPR crustal thickness is approximately 6–16 km,with a distinct discontinuity that is slightly thicker than the normal oceanic crust.The KPR mid-southern section crust structure was divided into four segments(S1–S4)from north to south,formed by the CBR eastward extension joint action and clockwise rotation of the PVB expansion axis and the Mindanao fault zone blocking effect. 展开更多
关键词 structural features satellite altimetry gravity data Kyushu-Palau Ridge central Basin Rift FAULTS Moho depth
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红河断裂带在莺歌海盆地的延伸——中央断裂的识别 被引量:1
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作者 付永涛 陈鹳霏 +5 位作者 吴涛 王万银 徐涛 王丁丁 周章国 杨安 《地质学报》 北大核心 2025年第3期704-718,共15页
红河断裂带的早期左行和后期右行走滑剪切作用对莺歌海盆地的构造演化和沉积过程具有重要的控制作用。虽然在莺歌海盆地的中央坳陷北部和南部已识别出红河断裂,但仍不清楚红河断裂带在中央坳陷是如何延伸的,因此对莺歌海盆地的构造演化... 红河断裂带的早期左行和后期右行走滑剪切作用对莺歌海盆地的构造演化和沉积过程具有重要的控制作用。虽然在莺歌海盆地的中央坳陷北部和南部已识别出红河断裂,但仍不清楚红河断裂带在中央坳陷是如何延伸的,因此对莺歌海盆地的构造演化和沉积过程研究造成了一定影响。目前多基于盆地东侧的1号断裂和西侧的莺西断裂为边界,研究莺歌海盆地的构造演化。本文基于莺歌海盆地卫星测高重力异常,采用重力异常归一化总水平导数垂向导数(NVDR-THDR)方法厘定了中央断裂的分布,且在中央坳陷北部和中部得到了2D地震剖面的证实。中央断裂是红河断裂带在莺歌海盆地的延伸,在东方底辟区以北发育左阶断层,在平面上形成向东的错断;在昌南底辟区以东为数条平行断层组成的断裂带,在乐东底辟区发展为左行左阶断层系,发育了乐东南洼陷(拉分盆地)。地震剖面显示中央断裂在中央坳陷的埋深较大,在双程旅行时长大于6 s的深度以下,依据地层层序判断其主要活动期为早于30 Ma并持续至15.98 Ma。依据双界面模型快速反演方法计算的莺歌海盆地沉积物厚度,在中央坳陷发育5个厚度大于15 km的沉降中心。总体上,中央断裂以西为沉降中心,以东为沉积深度变浅的梯度带。同时,中央坳陷的5个底辟构造带均分布于中央断裂以西,尤其是乐东区的左行左阶断层系对3个平行分布的底辟带有明显的控制作用。中央断裂对莺歌海盆地构造演化和油气勘探具有重要的意义。 展开更多
关键词 红河断裂带 莺歌海盆地 中央坳陷 中央断裂 卫星测高重力异常 沉积中心 底辟
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钴产业链全球贸易的国家地位与风险传播 被引量:1
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作者 郭尧琦 郑茹 《中南大学学报(社会科学版)》 北大核心 2025年第1期123-135,共13页
随着新能源成为新的经济增长点,钴作为新能源领域的重要原材料,其供应保障问题愈发凸显。从全产业链的视角解析钴贸易的风险传播过程,提出多属性引力中心性(MAGC)算法,识别2016—2022年钴产业链的核心贸易国家,并选择SIR模型进一步刻画... 随着新能源成为新的经济增长点,钴作为新能源领域的重要原材料,其供应保障问题愈发凸显。从全产业链的视角解析钴贸易的风险传播过程,提出多属性引力中心性(MAGC)算法,识别2016—2022年钴产业链的核心贸易国家,并选择SIR模型进一步刻画核心国家与边缘国家的风险传播效应。研究发现:钴产业链上中下游整体呈现以德国、中国与美国为核心的贸易格局,产业链贸易存在同质性;上游以荷兰、中国和美国为中心传播国家,各国的MAGC值整体偏小,中下游以中国、美国、德国为核心国家;当产业链面临风险时,一般在5个时间步以内恢复到风险之前的状态,下游是产业链中最脆弱的环节,核心国家仅需要2次传播就能将风险扩散给多数国家。 展开更多
关键词 产业链 核心国家 多属性引力中心性
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中原城市群多极网络空间组织的形成与识别 被引量:1
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作者 陈斐 沈炜怡 《浙江理工大学学报(社会科学版)》 2025年第1期29-38,共10页
基于多极网络空间组织的构成要素,采用社会网络分析方法分析2007—2022年中原城市群空间经济网络的特征及变化情况,运用引力模型和构建增长极指标来识别增长极,并利用共生度模型探究空间经济网络与多增长极之间的共生关系。研究结果表明... 基于多极网络空间组织的构成要素,采用社会网络分析方法分析2007—2022年中原城市群空间经济网络的特征及变化情况,运用引力模型和构建增长极指标来识别增长极,并利用共生度模型探究空间经济网络与多增长极之间的共生关系。研究结果表明:中原城市群空间经济网络整体发展水平稳步上升,“十”字形和“米”字形空间经济网络分别在2010年和2022年成型;形成了以郑州为增长极,洛阳、新乡和许昌为潜在增长极的“1+3”多极增长格局;中原城市群空间经济网络与多增长极具有互利共生关系。总体上,在中原城市群的发展过程已出现多极网络空间组织现象,正处于“多增长极、多层级、多节点”的空间发展状态。该研究识别了中原城市群的多极网络空间结构,并对中原城市群的发展提出了一定的政策启示。 展开更多
关键词 中原城市群 多极网络空间组织 增长极 空间经济网络 社会网络分析 引力模型
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宁波与中东欧国家进出口贸易合作潜力研究
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作者 钟建军 邵晔 王子童 《经济管理前沿》 2025年第4期6-9,共4页
中东欧国家是“一带一路”倡议对接欧洲经济圈的重要纽带,宁波作为中国—中东欧国家经贸合作示范区,在推动双边贸易中具有显著优势。本文基于2000-2016年贸易数据,运用引力模型分析宁波与中东欧国家的贸易潜力,发现宁波进口贸易效率均值... 中东欧国家是“一带一路”倡议对接欧洲经济圈的重要纽带,宁波作为中国—中东欧国家经贸合作示范区,在推动双边贸易中具有显著优势。本文基于2000-2016年贸易数据,运用引力模型分析宁波与中东欧国家的贸易潜力,发现宁波进口贸易效率均值为41.25(潜力再造型),出口贸易效率均值为5.45(潜力再造型),但市场集中度过高,需进一步优化结构。建议通过多元化贸易对象、提升经济自由化、加强政策协同等措施释放合作潜力。 展开更多
关键词 宁波—中东欧国家 进出口贸易 合作潜力 引力模型
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基于层加权和重力中心性的多层网络重要节点识别
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作者 王建波 罗雨 +2 位作者 许小可 杜占玮 李平 《计算机科学》 北大核心 2025年第12期92-101,共10页
识别多层网络中的重要节点是网络科学中的一个研究热点,对于理解网络的结构和功能起着至关重要的作用。受引力模型启发,现有大多数方法主要基于局部或全局拓扑结构信息,忽略了多层网络的层内和层间结构对节点的影响,限制了节点识别的最... 识别多层网络中的重要节点是网络科学中的一个研究热点,对于理解网络的结构和功能起着至关重要的作用。受引力模型启发,现有大多数方法主要基于局部或全局拓扑结构信息,忽略了多层网络的层内和层间结构对节点的影响,限制了节点识别的最终性能。对此,提出了一种基于层加权和重力中心性算法来识别多层网络的重要节点。首先,该算法结合网络的层内和层间结构赋予每层网络权重,以此量化度中心性在不同层的影响力。其次,考虑网络的层间结构对传播路径的影响,进而定义节点之间的有效距离。最后,根据引力公式获得节点在整个网络中的影响力值。在9个真实网络上的多个实验表明,所提算法与6种具有代表性的方法相比,具有较高的准确率和分辨率。 展开更多
关键词 影响力节点 引力模型 中心性 层权重 多层网络
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川中丘陵区生态网络识别与优化研究--以遂宁市为例 被引量:1
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作者 许晓露 周晓龙 +1 位作者 马俊强 王新文 《环境生态学》 2025年第8期81-88,共8页
川中丘陵区为川内重要经济发展区,但随着经济的发展,森林覆被率低、水土流失严重等生态环境问题也逐渐显现,因此识别现有生态网络是改善目前生态环境问题的重要前提。本研究以遂宁市为例,通过形态学空间格局分析(MSPA)方法和最小累积阻... 川中丘陵区为川内重要经济发展区,但随着经济的发展,森林覆被率低、水土流失严重等生态环境问题也逐渐显现,因此识别现有生态网络是改善目前生态环境问题的重要前提。本研究以遂宁市为例,通过形态学空间格局分析(MSPA)方法和最小累积阻力模型(MCR)识别重要生态源地和潜在生态廊道,结合重力模型提取重要生态廊道和一般生态廊道,形成遂宁市现有生态网络体系并提出生态网络优化建议。研究结果表明:(1)遂宁市核心区以林地为主,整体呈东密-中通-西疏分布。(2)现有生态网络空间分布不均,识别重要生态源地16个,潜在生态廊道126条,其中重要生态廊道25条,一般生态廊道101条。生态源地与生态廊道集中分布于遂宁市东部和中部,而北部和西南部较少。(3)通过在遂宁市北部以及西南部新增4个生态源地、64条生态廊道、设置17个踏脚石、识别53个生态断裂点,提高了生态网络闭合度、复杂度和连通度。研究结果可为遂宁市城市总体规划、国土空间规划等专项规划提供科学依据,同时也可为川中丘陵区其他城市生态网络识别与优化提供参考。 展开更多
关键词 川中丘陵区 生态网络 形态学空间格局 最小累积阻力模型 重力模型
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南海管事平顶海山密度结构及其构造意义
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作者 汪俊 王哲 +2 位作者 李书华 高红芳 黄永健 《吉林大学学报(地球科学版)》 北大核心 2025年第5期1691-1701,共11页
管事平顶海山地理位置处于南海17°N残留扩张脊附近,且东临马尼拉海沟。作为南海中央海盆最大的平顶海山,海山范围内的拖网岩石样品辉石~(40)Ar/~(39)Ar测年和全岩测年结果分别为(32.3±0.5)Ma和(28.9±1.9)Ma,指示其可能... 管事平顶海山地理位置处于南海17°N残留扩张脊附近,且东临马尼拉海沟。作为南海中央海盆最大的平顶海山,海山范围内的拖网岩石样品辉石~(40)Ar/~(39)Ar测年和全岩测年结果分别为(32.3±0.5)Ma和(28.9±1.9)Ma,指示其可能为南海中央海盆年龄最老的海山,这与当前主流研究的南海海盆扩张时间框架(约23.6 Ma)并不一致;且岩石样品全岩分析结果为MORB(mid-ocean ridge basalt)型大洋斜长花岗岩,使得管事平顶海山可能成为进一步认识南海海盆演化历史的重要研究区域。经初步测量得到岩石样品的密度在2.7573~2.9416 g/cm^(3)之间,中位数为2.8465 g/cm^(3)。构建了跨管事平顶海山的多道地震地层速度场,对时间域地震剖面解释资料进行时深转换得到深度域沉积基底结构,结合同测线重力资料开展重震联合建模试验,通过对多种建模方案的分析比较,认为管事平顶海山及地壳平均密度在2.70~2.75 g/cm^(3)之间,不排除海山南部局部区域可能存在密度大于2.80 g/cm^(3)的岩体,海山及地壳平均密度高于南海中央海盆停止扩张后的海山(2.60~2.70 g/cm^(3)),低于洋壳下地壳辉长岩(2.80~2.90 g/cm^(3))。综合考虑海山及地壳平均密度、多道地震成像、平顶海山形成原理,认为管事平顶海山可能是南海中央海盆海底扩张期间板内海山演化的产物。要解决板内海山演化过程中大洋斜长花岗岩如何形成的问题,需要探索更为合理的构造模式。 展开更多
关键词 管事平顶海山 南海中央海盆 重震联合建模 大洋斜长花岗岩 板内海山
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