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Image Processing on Geological Data in Vector Format and Multi-Source Spatial Data Fusion
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作者 Liu Xing Hu Guangdao Qiu Yubao Faculty of Earth Resources, China University of Geosciences, Wuhan 430074 《Journal of China University of Geosciences》 SCIE CSCD 2003年第3期278-282,共5页
The geological data are constructed in vector format in geographical information system (GIS) while other data such as remote sensing images, geographical data and geochemical data are saved in raster ones. This paper... The geological data are constructed in vector format in geographical information system (GIS) while other data such as remote sensing images, geographical data and geochemical data are saved in raster ones. This paper converts the vector data into 8 bit images according to their importance to mineralization each by programming. We can communicate the geological meaning with the raster images by this method. The paper also fuses geographical data and geochemical data with the programmed strata data. The result shows that image fusion can express different intensities effectively and visualize the structure characters in 2 dimensions. Furthermore, it also can produce optimized information from multi-source data and express them more directly. 展开更多
关键词 geological data GIS-based vector data conversion image processing multi-source data fusion
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Multi-Source Spatial Data Distribution Model and System Implementation
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作者 Jing Liu Xiancheng Mao 《Communications and Network》 2013年第1期93-98,共6页
The Multi-source spatial data distribution is based on WebGIS, and it is an important part of multi-source geographic information management system. a new multi-source spatial data distribution model is proposed on th... The Multi-source spatial data distribution is based on WebGIS, and it is an important part of multi-source geographic information management system. a new multi-source spatial data distribution model is proposed on the basis of multisource data storage model and by combining existing map distribution technology, The author developed a multi-source spatial data distribution system which based on MapGIS K9 by using this model and taking full advantage of interfacecode separating thinking and high efficiency characteristic of .net, so high-speed distribution of multi-source spatial data realized. 展开更多
关键词 multi-source SPATIAL data DISTRIBUTION Model WEBGIS MAPGIS K9
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A multi-source data fusion modeling method for debris flow prevention engineering 被引量:1
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作者 XU Qing-yang YE Jian LYU Yi-jie 《Journal of Mountain Science》 SCIE CSCD 2021年第4期1049-1061,共13页
The Digital Elevation Model(DEM)data of debris flow prevention engineering are the boundary of a debris flow prevention simulation,which provides accurate and reliable DEM data and is a key consideration in debris flo... The Digital Elevation Model(DEM)data of debris flow prevention engineering are the boundary of a debris flow prevention simulation,which provides accurate and reliable DEM data and is a key consideration in debris flow prevention simulations.Thus,this paper proposes a multi-source data fusion method.First,we constructed 3D models of debris flow prevention using virtual reality technology according to the relevant specifications.The 3D spatial data generated by 3D modeling were converted into DEM data for debris flow prevention engineering.Then,the accuracy and applicability of the DEM data were verified by the error analysis testing and fusion testing of the debris flow prevention simulation.Finally,we propose the Levels of Detail algorithm based on the quadtree structure to realize the visualization of a large-scale disaster prevention scene.The test results reveal that the data fusion method controlled the error rate of the DEM data of the debris flow prevention engineering within an allowable range and generated 3D volume data(obj format)to compensate for the deficiency of the DEM data whereby the 3D internal entity space is not expressed.Additionally,the levels of detailed method can dispatch the data of a large-scale debris flow hazard scene in real time to ensure a realistic 3D visualization.In summary,the proposed methods can be applied to the planning of debris flow prevention engineering and to the simulation of the debris flow prevention process. 展开更多
关键词 Debris flow prevention Level of detail Debris flow simulation multi platform fusion multi source data fusion
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Cycle-by-Cycle Queue Length Estimation for Signalized Intersections Using Multi-Source Data 被引量:4
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作者 Zhongyu Wang Qing Cai +2 位作者 Bing Wu Yinhai Wang Linbo Li 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2015年第2期86-93,共8页
In order to estimate vehicular queue length at signalized intersections accurately and overcome the shortcomings and restrictions of existing studies especially those based on shockwave theory,a new methodology is pre... In order to estimate vehicular queue length at signalized intersections accurately and overcome the shortcomings and restrictions of existing studies especially those based on shockwave theory,a new methodology is presented for estimating vehicular queue length using data from both point detectors and probe vehicles. The methodology applies the shockwave theory to model queue evolution over time and space. Using probe vehicle locations and times as well as point detector measured traffic states,analytical formulations for calculating the maximum and minimum( residual) queue length are developed. The proposed methodology is verified using ground truth data collected from numerical experiments conducted in Shanghai,China. It is found that the methodology has a mean absolute percentage error of 17. 09%,which is reasonably effective in estimating the queue length at traffic signalized intersections. Limitations of the proposed models and algorithms are also discussed in the paper. 展开更多
关键词 QUEUE LENGTH estimation multi-source data TRAFFIC SIGNALS TRAFFIC SHOCKWAVE theory
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Accessing Multi-Source Geological Data through Network in MORPAS Software System 被引量:3
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作者 MeiHongbo HuGuangdao +1 位作者 ChinJian~o LiZhenhua 《Journal of China University of Geosciences》 SCIE CSCD 2003年第3期265-268,共4页
MORPAS is a special GIS (geographic information system) software system, based on the MAPGIS platform whose aim is to prospect and evaluate mineral resources quantificationally by synthesizing geological, geophysical,... MORPAS is a special GIS (geographic information system) software system, based on the MAPGIS platform whose aim is to prospect and evaluate mineral resources quantificationally by synthesizing geological, geophysical, geochemical and remote sensing data. It overlays geological database management, geological background and geological abnormality analysis, image processing of remote sensing and comprehensive abnormality analysis, etc.. It puts forward an integrative solution for the application of GIS in basic-level units and the construction of information engineering in the geological field. As the popularization of computer networks and the request of data sharing, it is necessary to extend its functions in data management so that all its data files can be accessed in the network server. This paper utilizes some MAPGIS functions for the second development and ADO (access data object) technique to access multi-source geological data in SQL Server databases. Then remote visiting and congruous management will be realized in the MORPAS system. 展开更多
关键词 multi-source geological data SQL Server accessing data through network
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3D Geological Modeling with Multi-source Data Integration in Polymetallic Region:A Case Study of Luanchuan,Henan Province,China 被引量:1
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作者 Gongwen Wang~(1,2),Shouting Zhang~(1,2),Changhai Yan~3,Yaowu Song~3,Limei Wang~1 1.School of Earth Sciences and Resources,China University of Geosciences(Beijing),Beijing 100083,China. 2.State Key laboratory of Geological Processes and Mineral Resources,China University of Geosciences,Beijing 100083,China 3.Henan Institute of Geological Survey,Zhengzhou 450007,China 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期166-167,共2页
The development of 3D geological models involves the integration of large amounts of geological data,as well as additional accessible proprietary lithological, structural,geochemical,geophysical,and borehole data.Luan... The development of 3D geological models involves the integration of large amounts of geological data,as well as additional accessible proprietary lithological, structural,geochemical,geophysical,and borehole data.Luanchuan,the case study area,southwestern Henan Province,is an important molybdenum-tungsten -lead-zinc polymetallic belt in China. 展开更多
关键词 3D GEOLOGICAL modeling multi-source data MINERAL exploration METALLOGENIC model virtual GEOLOGICAL section Luanchuan POLYMETALLIC REGION
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Generation of daily snow depth from multi-source satellite images and in situ observations
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作者 CAO Guangzhen HOU Peng +1 位作者 ZHENG Zhaojun TANG Shihao 《Journal of Geographical Sciences》 SCIE CSCD 2015年第10期1235-1246,共12页
Snow depth (SD) is a key parameter for research into global climate changes and land surface processes. A method was developed to obtain daily SD images at a higher 4 km spatial resolution and higher precision with ... Snow depth (SD) is a key parameter for research into global climate changes and land surface processes. A method was developed to obtain daily SD images at a higher 4 km spatial resolution and higher precision with SD measurements from in situ observations and passive microwave remote sensing of Advanced Microwave Scanning Radiometer-EOS (AMSR-E) and snow cover measurements of the Interactive Multisensor Snow and Ice Mapping System (IMS). AMSR-E SD at 25 km spatial resolution was retrieved from AMSR-E products of snow density and snow water equivalent and then corrected using the SD from in situ observations and IMS snow cover. Corrected AMSR-E SD images were then resampled to act as "virtual" in situ observations to combine with the real in situ observations to interpolate at 4 km spatial resolution SD using the Cressman method. Finally, daily SD data generation for several regions of China demonstrated that the method is well suited to the generation of higher spatial resolution SD data in regions with a lower Digital Elevation Model (DEM) but not so well suited to regions at high altitude and with an undulating terrain, such as the Tibetan Plateau. Analysis of the longer time period SD data generation for January between 2003 and 2010 in northern Xinjiang also demonstrated the feasibility of the method. 展开更多
关键词 data fusion daily snow depth multi-source satellite images passive microwave remote sensing IMS in situ observations
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(EERSM): Energy-Efficient Multi-Hop Routing Technique in Wireless Sensor Networks Based on Combination between Stationary and Mobile Nodes
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作者 Fawaz Alassery 《Journal of Computer and Communications》 2019年第4期31-52,共22页
In Wireless Sensor Network (WSNs), sensor nodes collect data and send them to a Base Station (BS) for further processing. One of the most issues in WSNs that researchers have proposed a hundred of technique to solve i... In Wireless Sensor Network (WSNs), sensor nodes collect data and send them to a Base Station (BS) for further processing. One of the most issues in WSNs that researchers have proposed a hundred of technique to solve its impact is the energy constraint since sensor nodes have small battery, small memory and less data processing with low computational capabilities. However, many researches efforts have focused on how to prolong the battery lifetime of sensor nodes by proposing different routing, MAC, localization, data aggregation, topology construction techniques. In this paper, we will focus on routing techniques which aim to prolonging the network lifetime. Hence, we propose an Energy-Efficient Routing technique in WSNs based on Stationary and Mobile nodes (EERSM). Sensing filed is divided into intersected circles which contain Mobile Nodes (MN). The proposed data aggregation technique via the circular topology will eliminate the redundant data to be sent to the Base Station (BS). MN in each circle will rout packets for their source nodes, and move to the intersected area where another MN is waiting (sleep mode) to receive the transmitted packet, and then the packet will be delivered to the next intersected area until the packet is arrived to the BS. Our proposed EERSM technique is simulated using MATLAB and compared with conventional multi-hop techniques under different network models and scenarios. In the simulation, we will show how the proposed EERSM technique overcomes many routing protocols in terms of the number of hops counted when sending packets from a source node to the destination (i.e. BS), the average residual energy, number of sent packets to the BS, and the number of a live sensor nodes verse the simulation rounds. 展开更多
关键词 Energy Efficiency in WSNS data AGGREGATION of WSNS Mobile nodeS in WSNS multi-HOP Routing in WSNS Power Efficient Techniques
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Red Tide Information Extraction Based on Multi-source Remote Sensing Data in Haizhou Bay
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作者 LU Xia JIAO Ming-lian 《Meteorological and Environmental Research》 CAS 2011年第8期78-81,共4页
[Objective] The aim was to extract red tide information in Haizhou Bay on the basis of multi-source remote sensing data.[Method] Red tide in Haizhou Bay was studied based on multi-source remote sensing data,such as IR... [Objective] The aim was to extract red tide information in Haizhou Bay on the basis of multi-source remote sensing data.[Method] Red tide in Haizhou Bay was studied based on multi-source remote sensing data,such as IRS-P6 data on October 8,2005,Landsat 5-TM data on May 20,2006,MODIS 1B data on October 6,2006 and HY-1B second-grade data on April 22,2009,which were firstly preprocessed through geometric correction,atmospheric correction,image resizing and so on.At the same time,the synchronous environment monitoring data of red tide water were acquired.Then,band ratio method,chlorophyll-a concentration method and secondary filtering method were adopted to extract red tide information.[Result] On October 8,2005,the area of red tide was about 20.0 km2 in Haizhou Bay.There was no red tide in Haizhou bay on May 20,2006.On October 6,2006,large areas of red tide occurred in Haizhou bay,with area of 436.5 km2.On April 22,2009,red tide scattered in Haizhou bay,and its area was about 10.8 km2.[Conclusion] The research would provide technical ideas for the environmental monitoring department of Lianyungang to implement red tide forecast and warning effectively. 展开更多
关键词 Haizhou Bay Red tide monitoring region multi-source remote sensing data Secondary filtering method Band ratio method Chlorophyll-a concentration method China
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基于喀喇沁旗大西沟萤石矿区SPOT-5、Landsat-9和ASTER影像的多元信息提取和找矿预测
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作者 沈家乐 裴秋明 +4 位作者 张沥 韩术合 马少兵 陈磊 王世明 《地质论评》 北大核心 2025年第5期1774-1786,共13页
萤石是国家新一轮找矿突破战略行动重点关注的关键矿产,为更好地发挥遥感技术的先导性作用,探讨基于多源遥感数据的多元信息有效提取及萤石找矿预测具有重要意义。本研究以大兴安岭南段大西沟大型脉状萤石矿床为试验区,首先利用SPOT-5... 萤石是国家新一轮找矿突破战略行动重点关注的关键矿产,为更好地发挥遥感技术的先导性作用,探讨基于多源遥感数据的多元信息有效提取及萤石找矿预测具有重要意义。本研究以大兴安岭南段大西沟大型脉状萤石矿床为试验区,首先利用SPOT-5高分辨率影像解译了地质构造,并通过最小噪声分离法有效解译了地层岩性。基于主成分分析方法,使用Landsat-9和ASTER两种遥感数据提取了研究区羟基和铁染蚀变信息,依据ASTER SiO_(2)发射率光谱与化学成分的数值关系提取了硅化蚀变信息。通过已知矿点的蚀变异常检验和对比分析,发现羟基蚀变异常和硅化蚀变异常与萤石矿化关系密切,且不同遥感数据提取的蚀变异常重叠区域示矿效果更好。基于萤石矿脉赋存对于围岩没有特别选择性,且具有明显的构造控矿及蚀变发育特征,利用GIS平台同时考虑构造和蚀变两种因素,叠加基于三种遥感数据提取的异常信息进行综合预测,结果显示圈定的成矿远景区与已知矿点高度吻合,并在矿区外围新预测了两处找矿靶区。本研究对于该区后期外围找矿具有指导作用,对其他地区脉状萤石矿床的遥感找矿预测亦具有推广应用价值。 展开更多
关键词 萤石矿床 热液脉型 多源遥感数据 蚀变信息提取 大兴安岭南段
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Extracting a Heterogeneous Social Network of AcademicResearchers on the Web Based on Information Retrieved from Multiple Sources 被引量:2
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作者 Rasim M. Alguliev Ramiz M Aliguliyev Fadai S Ganjaliyev 《American Journal of Operations Research》 2011年第2期33-38,共6页
The majority of academic researchers present the results of their scientific activity on the Web. This trace can be used to derive useful information of their past, present activity and forecast the future intentions.... The majority of academic researchers present the results of their scientific activity on the Web. This trace can be used to derive useful information of their past, present activity and forecast the future intentions. Hence, social network of academic researchers can be of important value for scientific community. This information can be retrieved from various data source currently available on the Web. From each of them a separate net-work can be built. In this paper we present a method which can be used to combine multiple single-relational networks into a single network which will combine all relations, hence it will be multi-relational. 展开更多
关键词 multi-Relational Networks ACADEMIC Researchers’ Network data source CRITERIA
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Paddy Rice Mapping Based on Phenology Matching and Cultivation Pattern Analysis Combining Multi-Source Data in Guangdong,China 被引量:1
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作者 Lingyu Sun Tianyao Yang +2 位作者 Yuxin Lou Qian Shi Liangpei Zhang 《Journal of Remote Sensing》 2024年第1期413-430,共18页
Paddy rice mapping is crucial for cultivation management,yield estimation,and food security.Guangdong,straddling tropics and subtropics,is a major rice-producing region in China.Mapping paddy rice in Guangdong is esse... Paddy rice mapping is crucial for cultivation management,yield estimation,and food security.Guangdong,straddling tropics and subtropics,is a major rice-producing region in China.Mapping paddy rice in Guangdong is essential.However,there are 2 main difficulties in tropical and subtropical paddy rice mapping,including the lack of high-quality optical images and differences in paddy rice planting times.This study proposed a paddy rice mapping framework using phenology matching,integrating Sentinel-1 and Sentinel-2 data to incorporate prior knowledge into the classifiers.The transplanting periods of paddy rice were identified with Sentinel-1 data,and the subsequent 3 months were defined as the growth periods.Features during growth periods obtained by Sentinel-1 and Sentinel-2 were inputted into machine learning classifiers.The classifiers using matched features substantially improved mapping accuracy compared with those using unmatched features,both for early and late rice mapping.The proposed method also improved the accuracy by 6.44%to 16.10%compared with 3 other comparison methods.The model,utilizing matched features,was applied to early and late rice mapping in Guangdong in 2020.Regression results between mapping area and statistical data validate paddy rice mapping credibility.Our analysis revealed that thermal conditions,especially cold severity during growing stages,are the primary determinant of paddy rice phenology.Spatial patterns of paddy rice in Guangdong result from a blend of human and physical factors,with slope and minimum temperature emerging as the most important limitations.These findings enhance our understanding of rice ecosystems’dynamics,offering insights for formulating relevant agricultural policies. 展开更多
关键词 phenology matching machine learning classifiers paddy rice phenology matchingintegrating paddy rice mapping cultivation pattern analysis multi source data food security
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基于Multi-Agent的多数据源WebGIS研究 被引量:2
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作者 杨颖 张虎 +1 位作者 陈湘国 吴开兴 《计算机技术与发展》 2006年第6期121-123,126,共4页
通过对多数据源WebGIS的特点以及Multi-Agent技术的分析,基于对原有多数据源WebGIS体系进行改进的目的,应用面向Agent的程序设计方法(AOP)提出了基于Multi-Agent的多数据源WebGIS系统框架。这对解决多格式数据直接访问,格式无关、位置... 通过对多数据源WebGIS的特点以及Multi-Agent技术的分析,基于对原有多数据源WebGIS体系进行改进的目的,应用面向Agent的程序设计方法(AOP)提出了基于Multi-Agent的多数据源WebGIS系统框架。这对解决多格式数据直接访问,格式无关、位置无关数据集成,多源数据复合分析等不同格式数据资源的综合利用问题,实现多源异构空间数据有效的无缝集成,进一步实现真正意义上的WebGIS,具有一定理论和实践意义。 展开更多
关键词 multi—AGENT 多数据源 WEBGIS
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Overview of global monthly surface temperature data in the past century and preliminary integration 被引量:2
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作者 XU Wen-Hui LI Qing-Xiang +1 位作者 YANG Su XU Yan 《Advances in Climate Change Research》 SCIE 2014年第3期111-117,共7页
This paper analyzes the status of existing resources through extensive research and international cooperation on the basis of four typical global monthly surface temperature datasets including the climate research dat... This paper analyzes the status of existing resources through extensive research and international cooperation on the basis of four typical global monthly surface temperature datasets including the climate research dataset of the University of East Anglia(CRUTEM3), the dataset of the U.S. National Climatic Data Center(GHCN-V3), the dataset of the U.S. National Aeronautics and Space Administration(GISSTMP), and the Berkeley Earth surface temperature dataset(Berkeley). China's first global monthly temperature dataset over land was developed by integrating the four aforementioned global temperature datasets and several regional datasets from major countries or regions. This dataset contains information from 9,519 stations worldwide of at least 20 years for monthly mean temperature, 7,073 for maximum temperature, and 6,587 for minimum temperature. Compared with CRUTEM3 and GHCN-V3, the station density is much higher particularly for South America, Africa,and Asia. Moreover, data from significantly more stations were available after the year 1990 which dramatically reduced the uncertainty of the estimated global temperature trend during 1990e2011. The integrated dataset can serve as a reliable data source for global climate change research. 展开更多
关键词 GLOBAL MONTHLY SURFACE temperature dataset INTEGRATION of multi-source data Climate change
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调查数据匮乏区域的森林景观模型验证:以LANDIS PRO模型模拟青藏高原森林景观动态为例
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作者 张鹏超 梁宇 +2 位作者 吴苗苗 刘波 马天啸 《生态学杂志》 CAS CSCD 北大核心 2024年第6期1549-1557,共9页
森林景观模型(forest landscape model,FLM)已成为模拟森林景观动态的重要工具,模型预测的有效性将决定FLM在森林管理应用中的广度和深度。有限的调查数据是制约模型验证的主要原因,选择合适的方法来弥补数据的空缺并解决数据匮乏地区... 森林景观模型(forest landscape model,FLM)已成为模拟森林景观动态的重要工具,模型预测的有效性将决定FLM在森林管理应用中的广度和深度。有限的调查数据是制约模型验证的主要原因,选择合适的方法来弥补数据的空缺并解决数据匮乏地区的模型验证问题可促进FLM得到更广泛的应用。本研究基于多源数据和时空代替法在森林调查数据匮乏的区域建立模型验证框架,并以LANDIS PRO森林景观模型模拟青藏高原未来森林景观动态为例说明该框架的适用性。具体的验证框架为:首先,使用森林调查数据校验模型参数;其次,利用多源数据(森林调查数据、遥感产品和已有研究结果)对模型结果进行短期验证;最后基于时空代替法和已有研究验证模型的长期结果。验证结果表明:初始模拟结果能够准确表征真实的森林属性信息;基于多种指标的LANDIS PRO短期模拟结果在样地和景观尺度上与验证数据差异较小(RMSE<80 t·hm^(-2)、SD<80 t·hm^(-2)、R^(2)=0.81);长期林分动态特征与先前研究一致,模型预测的森林组成、结构和演替轨迹与该区原生林生长轨迹一致。这表明本研究基于森林资源数据匮乏条件建立的森林景观模型验证框架能够较好地对森林景观的模拟结果进行验证。 展开更多
关键词 模型验证框架 时空代替法 多源数据 森林数据匮乏区
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基于多源遥感数据的城市道路坍塌易发性预测 被引量:2
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作者 王明常 于海滨 +6 位作者 曾昭发 王典 韩复兴 张剑 罗修杰 冷亮 刘子维 《吉林大学学报(地球科学版)》 北大核心 2025年第3期1028-1038,共11页
城市道路坍塌是严重的城市安全问题,可能导致人员伤亡和交通中断,对城市运行和社会发展构成威胁。准确预测城市道路坍塌并分析其时空动态变化对城市安全具有重要意义。本研究以广东省深圳市福田区为研究区,利用多源遥感数据,结合随机森... 城市道路坍塌是严重的城市安全问题,可能导致人员伤亡和交通中断,对城市运行和社会发展构成威胁。准确预测城市道路坍塌并分析其时空动态变化对城市安全具有重要意义。本研究以广东省深圳市福田区为研究区,利用多源遥感数据,结合随机森林算法构建了一种城市道路坍塌易发性预测模型,并分析影响模型预测性能的关键指标和城市道路坍塌易发性的关键驱动因素。城市道路坍塌易发性时空预测结果表明:结合光学数据和雷达数据构建的城市道路坍塌易发性预测模型能够比较准确地预测道路坍塌易发性的时空变化,预测决定系数为0.65,预测精度较高;2017—2022年,福田区道路坍塌风险整体呈上升趋势,极低易发区和低易发区面积减少,中易发区和高易发区面积增加。随机森林特征重要性分析结果表明,基于影像数据提取的纹理特征对预测模型贡献度较高。根据地理探测器结果可知,人口、GDP和地下设施是影响城市道路坍塌的三个关键驱动因素。 展开更多
关键词 道路坍塌 随机森林 多源遥感数据 时空变化 广东省深圳市福田区
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技术生命周期视角下颠覆性技术早期识别方法研究 被引量:2
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作者 侯艳辉 陈荣 王家坤 《情报学报》 北大核心 2025年第2期157-170,共14页
针对目前颠覆性技术识别过程中忽略技术演化特征的问题,本文提出一种考虑技术生命周期阶段性和特征异质性的颠覆性技术早期识别方法。首先,采用Sentence-BERT (sentence bidirectional encoder representation from transformers)对专... 针对目前颠覆性技术识别过程中忽略技术演化特征的问题,本文提出一种考虑技术生命周期阶段性和特征异质性的颠覆性技术早期识别方法。首先,采用Sentence-BERT (sentence bidirectional encoder representation from transformers)对专利摘要进行向量化。其次,构建过滤识别系统。第一层使用LOCI (local outlier factor with constraint integration)异常检测算法识别离群专利并分类;第二层,采用S曲线生命周期识别,对处于成熟期的专利类别进行过滤;第三层,对萌芽阶段的专利进行创新性测度;第四层,对成长阶段的专利文本、技术报道数据进行颠覆性测度,完成过滤。最后,以量子信息技术领域为例,阐述该识别方法的应用过程。研究结果表明,量子信息领域共发现三个萌芽期颠覆性主题和三个成长期颠覆性主题,与官方发布的报告进行对比,结果一致,验证了本文方法的可行性与有效性。 展开更多
关键词 技术生命周期 早期识别 过滤识别 多源数据 量子信息
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基于无人机多源遥感数据和机器学习的高通量棉花估产研究 被引量:1
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作者 冯美臣 苏悦 +3 位作者 林涛 余汛 宋扬 金秀良 《农业机械学报》 北大核心 2025年第3期169-179,共11页
为综合利用光谱、冠层结构、纹理特征等信息对棉花进行无人机(Unmanned aerial vehicle,UAV)遥感产量估算并系统地分析光谱、冠层结构、纹理特征等信息对估产的贡献程度,本文在构建基于多源UAV数据棉花估产机器学习模型的基础上,进一步... 为综合利用光谱、冠层结构、纹理特征等信息对棉花进行无人机(Unmanned aerial vehicle,UAV)遥感产量估算并系统地分析光谱、冠层结构、纹理特征等信息对估产的贡献程度,本文在构建基于多源UAV数据棉花估产机器学习模型的基础上,进一步确定了估产的最佳生育时期,并对比了多源传感器数据在棉花产量估算中的效果,最后量化了各类输入特征的贡献度。采集棉花冠层RGB(Red green blue)、多光谱(Multispectral,MS)和激光雷达(Light detection and ranging,LiDAR)3种传感器数据,通过对棉花光谱植被指数与产量进行相关性分析,确定了棉花产量估算最佳生育时期,进而构建了基于偏最小二乘法回归(Partial least squares regression,PLSR)、随机森林回归(Random forest regression,RFR)、极致梯度提升(Extreme gradient boost,XGBoost)3种机器学习模型的棉花产量估算方法,并评估了基于2种最常用的传感器(RGB和MS相机)的性能。最终确定了光谱特征、冠层结构、纹理特征这3类特征信息在产量估算中的贡献度。研究结果表明,盛花期是棉花估产的最佳生育时期;基于盛花期的UAV数据,XGBoost模型取得了最高的产量估算精度(R^(2)为0.70,RMSE为611.31 kg/hm^(2),rRMSE为10.60%),在对比基于RGB和MS图像数据提取的特征时,基于MS图像数据提取的特征建模结果更好,同时将RGB和MS相机2种传感器数据提取的特征作为输入时,模型结果高于单一传感器;使用夏普利加性解释(Shapley additive explanations,SHAP)算法分析了机器学习模型中各个输入特征对于估产的贡献度,发现基于3种传感器的3种特征信息在产量估算方面都具有重要意义,其中,纹理特征与冠层结构在产量估算中展现出了较好的潜力。本研究可为棉花智慧化管理中高通量棉花产量估算提供理论和技术支持。 展开更多
关键词 棉花 估产 无人机遥感 多源数据 XGBoost 夏普利加性解释
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基于多源数据的柴达木盆地降水同位素特征研究 被引量:1
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作者 王涛 李其发 +2 位作者 张茜 王媛 陈建生 《河海大学学报(自然科学版)》 北大核心 2025年第2期29-38,共10页
为解决采用单一来源数据研究柴达木盆地降水同位素组成时空分布特征的局限性,综合利用TNIP数据、文献数据、C-Isoscape数据和GCMs数据,构建了当地大气降水线(LMWL),分析了柴达木盆地区域降水同位素组成的年内、年际变化及其温度和降水... 为解决采用单一来源数据研究柴达木盆地降水同位素组成时空分布特征的局限性,综合利用TNIP数据、文献数据、C-Isoscape数据和GCMs数据,构建了当地大气降水线(LMWL),分析了柴达木盆地区域降水同位素组成的年内、年际变化及其温度和降水量效应。结果表明:LMWL的斜率和截距低于GMWL,在空间分布上斜率呈现自西向东逐渐增大的趋势,这归因于云下二次蒸发的差异;降水δ^(18)O在年内尺度上呈现夏高冬低的季节变化特征;德令哈、小灶火、茫崖、大柴旦、乌兰站的降水δ^(18)O呈现逐年富集的变化趋势,温度是影响降水同位素年际变化的重要因素;柴达木盆地区域降水同位素温度效应显著,而降水量效应不明显。 展开更多
关键词 同位素特征 大气降水 多源数据 水文循环 柴达木盆地
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多源异质数据下深度神经网络的整合分析及其应用 被引量:1
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作者 王小燕 冮建伟 +1 位作者 王洁丹 王德青 《统计研究》 北大核心 2025年第2期122-134,共13页
随着计算机技术的发展,各行各业累积和存储了丰富的数据。这些数据往往具有来源差异性、高维性特点,基于这些特征的多源数据建模是统计学的热点问题。针对多源异质数据,本文提出深度神经网络整合分析模型(IADNN)。该模型建立了L_(1)-CMC... 随着计算机技术的发展,各行各业累积和存储了丰富的数据。这些数据往往具有来源差异性、高维性特点,基于这些特征的多源数据建模是统计学的热点问题。针对多源异质数据,本文提出深度神经网络整合分析模型(IADNN)。该模型建立了L_(1)-CMCP惩罚,以识别重要特征以及处理数据的异质性,其中外层MCP识别对多源数据集整体显著的特征;中层MCP识别特征在数据集层面的异质性;内层Lasso识别DNN节点的异质性。这种嵌套设计旨在促进数据集间的信息共享。本文对L_(1)-CMCP进行局部线性近似,再采用近端梯度下降算法进行模型估计。模拟分析表明,IADNN在特征选择和分类预测方面均有良好表现。当多源数据部分异质时,所提方法的F_(1)分数、FPR等评估指标均优于各数据集独立建模和合并建模的方法;在多源数据完全异质或完全同质时,所提方法取得了与理论最佳模型相近的效果。最后,将IADNN应用于不同经济发展水平地区的信用违约数据,发现该模型在风险指标选择和违约预测方面具备有效性。 展开更多
关键词 多源数据 整合分析 深度神经网络 信用评分
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