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Litho-Tectonic Architecture of the Dialafara Area, Kédougou-Kéniéba Inlier, Integration of New Field Data and Geophysics
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作者 Mahamadou Diallo Mamadou Yossi +2 位作者 Ibrahim Méyès Coulibaly Youssouf Son Amako Dolo 《Open Journal of Geology》 CAS 2024年第3期279-297,共19页
The Dialafara area is part of the highly endowed Kédougou-Kéniéba Inlier (KKI), West-Malian gold belt, which corresponds to a Paleoproterozoic window through the West African Craton (WAC). This study pr... The Dialafara area is part of the highly endowed Kédougou-Kéniéba Inlier (KKI), West-Malian gold belt, which corresponds to a Paleoproterozoic window through the West African Craton (WAC). This study presents, first of all, an integration of geophysical data interpretation with litho-structural field reconnaissance and then proposes a new litho-structural map of the Dialafara area. The Dialafara area shows a variety of lithology characterized by volcanic and volcano-sedimentary units, metasediments and plutonic intrusion. These lithologies were affected by a complex superposition of structures of unequal importance defining three deformation phases (D<sub>D1</sub> to D<sub>D3</sub>) under ductile to brittle regimes. These features permit to portray a new litho-structural map, which shows that the Dialafara area presents a more complex lithological and structural context than the one presented in regional map of the KKI. This leads to the evidence that this area could be a potential site for exploration as it is situated between two world-class gold districts. 展开更多
关键词 Kédougou-Kéniéba Inlier Dialafara mapPING Aeromagnetic data Structure
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XML-based integration data model and schema mappingin multidatabase systems 被引量:5
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作者 LiRuixuan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第2期437-444,共8页
Multidatabase systems are designed to achieve schema integration and data interoperation among distributed and heterogeneous database systems. But data model heterogeneity and schema heterogeneity make this a challeng... Multidatabase systems are designed to achieve schema integration and data interoperation among distributed and heterogeneous database systems. But data model heterogeneity and schema heterogeneity make this a challenging task. A multidatabase common data model is firstly introduced based on XML, named XML-based Integration Data Model (XIDM), which is suitable for integrating different types of schemas. Then an approach of schema mappings based on XIDM in multidatabase systems has been presented. The mappings include global mappings, dealing with horizontal and vertical partitioning between global schemas and export schemas, and local mappings, processing the transformation between export schemas and local schemas. Finally, the illustration and implementation of schema mappings in a multidatabase prototype - Panorama system are also discussed. The implementation results demonstrate that the XIDM is an efficient model for managing multiple heterogeneous data sources and the approaches of schema mapping based on XIDM behave very well when integrating relational, object-oriented database systems and other file systems. 展开更多
关键词 multidatabase systems common data model schema mapping extensible markup language (XML).
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Lithological mapping with multispectral data–setup and application of a spectral database for rocks in the Balakot area, Northern Pakistan
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作者 Michael FUCHS Adnan A.AWAN +4 位作者 Sardar S.AKHTAR Ijaz AHMAD Simon SADIQ Asif RAZZAK Naghmah HAIDER 《Journal of Mountain Science》 SCIE CSCD 2017年第5期948-963,共16页
In the frame of landslide susceptibility assessment, a spectral library was created to support the identification of materials confined to a particular region using remote sensing images. This library, called Pakistan... In the frame of landslide susceptibility assessment, a spectral library was created to support the identification of materials confined to a particular region using remote sensing images. This library, called Pakistan spectral library(pklib) version 0.1, contains the analysis data of sixty rock samples taken in the Balakot region in Northern Pakistan.The spectral library is implemented as SQLite database. Structure and naming are inspired by the convention system of the ASTER Spectral Library. Usability, application and benefit of the pklib were evaluated and depicted taking two approaches, the multivariate and the spectral based. The spectral information were used to create indices. The indices were applied to Landsat and ASTER data tosupportthespatial delineation of outcropping rock sequences instratigraphic formations. The application of the indices introduced in this paper helps to identify spots where specific lithological characteristics occur. Especially in areas with sparse or missing detailed geological mapping, the spectral discrimination via remote sensing data can speed up the survey. The library can be used not only to support the improvement of factor maps for landslide susceptibility analysis, but also to provide a geoscientific basisto further analyze the lithological spotin numerous regions in the Hindu Kush. 展开更多
关键词 Lithological mapping Multispectral data Spectral library Normalized difference index Northern Pakistan
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利用WGS84-AW3D30 DSM data map表面模型数据作西安80或国家2000大地坐标系统的地形图技术探讨
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作者 叶育松 张雄天 《世界有色金属》 2022年第18期24-27,共4页
针对日常野外测绘及地形图绘制过程中存在的各种问题,本文提供了一种快速、简洁的地形图绘制方法,即利用现成的网络上得到的数据通过一系列的坐标系统转换过程得到工作所需的数据,并完成地形图绘制,为地形图绘制提供了一种新的思路。
关键词 WGS84-AW3D30 DSM data map表面模型数据 西安80坐标系 2000国家大地坐标系
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Interactive Generalization on Large-Scale Topographical Map Supported by a Database Platform
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作者 CAIZhongliang WUHehai +1 位作者 DUQingyun LIAOChujiang 《Geo-Spatial Information Science》 2003年第4期17-26,共10页
This paper makes astudy on the interactive digital gener-alization, where map generalizationcan be divided into intellective reason-ing procedure and operational proce-dure, which are done by human andcomputer, respec... This paper makes astudy on the interactive digital gener-alization, where map generalizationcan be divided into intellective reason-ing procedure and operational proce-dure, which are done by human andcomputer, respectively. And an inter-active map generalization environmentfor large scale topographic map is thendesigned and realized. This researchfocuses on: ① the significance of re-searching an interactive map generali-zation environment, ② the features oflarge scale topographic map and inter-active map generalization, ③ the con-struction of map generalization-orien-ted database platform. 展开更多
关键词 地形图 数据库 数字 交互式 人工智能
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基于Teigha.NET和MapWinGIS的多源异构测绘数据管理系统设计与实现 被引量:1
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作者 何清 《安徽地质》 2023年第2期158-161,共4页
遥感和计算机技术为传统测绘行业带来了新的发展机遇,测绘观测手段的多样化使得测绘数据种类逐渐增加,形成了海量的多源异构数据。传统数据存储管理方式难以有效支撑大数据的存储和高效处理分析,为解决这一难题,本研究提出了一种多源异... 遥感和计算机技术为传统测绘行业带来了新的发展机遇,测绘观测手段的多样化使得测绘数据种类逐渐增加,形成了海量的多源异构数据。传统数据存储管理方式难以有效支撑大数据的存储和高效处理分析,为解决这一难题,本研究提出了一种多源异构数据统一整合方法。采用C#语言、PostgreSQL数据库、MapWinGIS二次开发和Teigha.NET二次开发等多种开发手段,并结合混合编程方式开发了多源异构测绘数据管理系统。系统完全使用开源软件进行二次开发,脱离了AutoCAD等商业软件环境,针对不同空间基准、不同格式的测绘数据,实现了多源异构数据的结构转换及坐标转换,对多源异构测绘数据的存储和有效利用具有一定的参考价值。 展开更多
关键词 多源异构 测绘数据 GIS 数据管理 开源软件
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Three Applications of V.3 Google Maps: Just for Display of Data, or Analysis as Well?
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作者 Alan G. Phipps 《Journal of Geographic Information System》 2014年第5期548-558,共11页
A question about the analytical capability of Google maps is answered for three examples of pin maps, and polyline and polygon maps that are computer-programmed with the third version of the Google maps application. O... A question about the analytical capability of Google maps is answered for three examples of pin maps, and polyline and polygon maps that are computer-programmed with the third version of the Google maps application. One map reads XML data stored on the home server, whereas another downloads its data from an online fusion table, and the third includes pre-programmed data. Each map permits users to query mashup layers after the map has loaded. However, an analytical capability comparable to GIS should require users to have access to their data for analysis with their own functions while the map is loading. The technical constraint of asynchronous loading of data for Google maps is illustrated for each map. In conclusion, only one map has an analytical capability that is achieved by means of deprecated synchronous loading of data. 展开更多
关键词 V.3 Google mapS Pin mapS POLYGON mapS XML data Fusion Table Asynchronous Loading
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SMT: A SPATIAL MAPPING TOOL FOR STATISTICAL DATA SET
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作者 Wang Xuejun Department of Urban and Environmental Sciences Peking University, Beijing 100871 People’s Republic of China 《Journal of Geographical Sciences》 SCIE CSCD 1997年第1期85-92,共8页
The statistical map is usually used to indicate the quantitative features of various socio economic phenomena among regions on the base map of administrative divisions or on other base maps which connected with stati... The statistical map is usually used to indicate the quantitative features of various socio economic phenomena among regions on the base map of administrative divisions or on other base maps which connected with statistical unit. Making use of geographic information system (GIS) techniques, and supported by Auto CAD software, the author of this paper has put forward a practical method for making statistical map and developed a software (SMT) for the making of small scale statistical map using C language. 展开更多
关键词 statistical map geographic information system topological data structure.
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Land Cover Map Delineation, for Agriculture Development, Case Study in North Sinai, Egypt Using SPOT4 Data and Geographic Information System
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作者 Nasser H. Saleh Mohamed A. Aboelghar 《Advances in Remote Sensing》 2013年第1期35-43,共9页
Land cover map for a part of North Sinai was produced using the FAO—Land Cover Classification System (LCCS) of 2004. The standard FAO classification scheme provides a standardized system of classification that can be... Land cover map for a part of North Sinai was produced using the FAO—Land Cover Classification System (LCCS) of 2004. The standard FAO classification scheme provides a standardized system of classification that can be used to analyze spatial and temporal land cover variability in the study area. This approach also has the advantage of facilitating the integration of Sinai land cover mapping products to be included with the regional and global land cover datasets. The total study area is 7450 km2 (1,773,842) feddans. The landscape classification was performed on SPOT4 data acquired in 2011 using combined multi-spectral bands of 20 meter spatial resolution. Geographic Information System (GIS) was used to edit the classification result in order to reach the maximum possible accuracy. GIS was also used to include all necessary information. The identified vegetative land cover classes of the study area are irrigated herbaceous crops, irrigated tree crops and rain fed tree crops. The non-vegetated land covers in the study area include: bare rock, bare soil, bare soil stony, bare soil very stony, bare soil salt crusts, loose and shifting sands and sand dunes. The water bodies were classified as artificial perennial water bodies (fish ponds and irrigated canals) and natural perennial water bodies as lakes (standing) and rivers (flowing). Artificial surfaces in the study area include linear and non-linear. The produced maps and the statistics of the different land covers are included in the following sub-sections. 展开更多
关键词 SPOT data Land COVER mapping LCCS System
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The Optimization and Improvement of MapReduce in Web Data Mining
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作者 Jun Qu Chang-Qing Yin Shangwei Song 《Journal of Software Engineering and Applications》 2015年第8期395-406,共12页
Extracting and mining social networks information from massive Web data is of both theoretical and practical significance. However, one of definite features of this task was a large scale data processing, which remain... Extracting and mining social networks information from massive Web data is of both theoretical and practical significance. However, one of definite features of this task was a large scale data processing, which remained to be a great challenge that would be addressed. MapReduce is a kind of distributed programming model. Just through the implementation of map and reduce those two functions, the distributed tasks can work well. Nevertheless, this model does not directly support heterogeneous datasets processing, while heterogeneous datasets are common in Web. This article proposes a new framework which improves original MapReduce framework into a new one called Map-Reduce-Merge. It adds merge phase that can efficiently solve the problems of heterogeneous data processing. At the same time, some works of optimization and improvement are done based on the features of Web data. 展开更多
关键词 CLOUD COMPUTING Web data mapREDUCE map-Reduce-Merge
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Machine Learning Mapping of Soil Apparent Electrical Conductivity on a Research Farm in Mississippi
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作者 Reginald S. Fletcher 《Agricultural Sciences》 2023年第7期915-924,共10页
Open-source and free tools are readily available to the public to process data and assist producers in making management decisions related to agricultural landscapes. On-the-go soil sensors are being used as a proxy t... Open-source and free tools are readily available to the public to process data and assist producers in making management decisions related to agricultural landscapes. On-the-go soil sensors are being used as a proxy to develop digital soil maps because of the data they can collect and their ability to cover a large area quickly. Machine learning, a subcomponent of artificial intelligence, makes predictions from data. Intermixing open-source tools, on-the-go sensor technologies, and machine learning may improve Mississippi soil mapping and crop production. This study aimed to evaluate machine learning for mapping apparent soil electrical conductivity (EC<sub>a</sub>) collected with an on-the-go sensor system at two sites (i.e., MF2, MF9) on a research farm in Mississippi. Machine learning tools (support vector machine) incorporated in Smart-Map, an open-source application, were used to evaluate the sites and derive the apparent electrical conductivity maps. Autocorrelation of the shallow (EC<sub>as</sub>) and deep (EC<sub>ad</sub>) readings was statistically significant at both locations (Moran’s I, p 0.001);however, the spatial correlation was greater at MF2. According to the leave-one-out cross-validation results, the best models were developed for EC<sub>as</sub> versus EC<sub>ad</sub>. Spatial patterns were observed for the EC<sub>as</sub> and EC<sub>ad</sub> readings in both fields. The patterns observed for the EC<sub>ad</sub> readings were more distinct than the EC<sub>as</sub> measurements. The research results indicated that machine learning was valuable for deriving apparent electrical conductivity maps in two Mississippi fields. Location and depth played a role in the machine learner’s ability to develop maps. 展开更多
关键词 Spatial Variability Machine Learning Electrical Conductivity mapPING data Mining
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基于bit-map算法的DMA数据流仲裁器设计
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作者 朱亚琦 侯晓娟 《单片机与嵌入式系统应用》 2023年第9期74-77,82,共5页
针对集成电路产业快速发展所需要的复杂通信要求,设计了一种基于bit-map算法的DMA数据流仲裁器。DMA数据流仲裁器由通道优先级bit-map映射模块、通道请求生成模块、通道请求仲裁模块、通道授权标志生成模块和外设请求应答模块组成。在... 针对集成电路产业快速发展所需要的复杂通信要求,设计了一种基于bit-map算法的DMA数据流仲裁器。DMA数据流仲裁器由通道优先级bit-map映射模块、通道请求生成模块、通道请求仲裁模块、通道授权标志生成模块和外设请求应答模块组成。在完成逻辑设计后,通过UVM验证方法学对电路的各个功能进行验证。验证结果表明,本设计仅使用一个32位bit-map映射寄存器将8条通道的32种优先级配置映射到对应有效位,便可实现对8条通道DMA请求的仲裁,无需配置优先级比较电路,不会因逐级比较产生优先级配置相互干扰的问题,且在后期生成实际电路的过程中可以减小电路面积、降低电路功耗。 展开更多
关键词 bit-map DMA 数据流仲裁器 UVM
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Multidimensional Design Paradigms for Data Warehouses: A Systematic Mapping Study
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作者 Ania Cravero Samuel Sepúlveda 《Journal of Software Engineering and Applications》 2014年第1期53-61,共9页
Data warehouses (DW) must integrate information from the different areas and sources of an organization in order to extract knowledge relevant to decision-making. The DW development is not an easy task, which is why v... Data warehouses (DW) must integrate information from the different areas and sources of an organization in order to extract knowledge relevant to decision-making. The DW development is not an easy task, which is why various design approaches have been put forward. These approaches can be classified in three different paradigms according to the origin of the information requirements: supply-driven, demand-driven, and hybrids of these. This article compares the methodologies for the multidimensional design of DW through a systematic mapping as research methodology. The study is presented for each paradigm, the main characteristics of the methodologies, their notations and problem areas exhibited in each one of them. The results indicate that there is no follow-up to the complete process of implementing a DW in either an academic or industrial environment;however, there is also no evidence that the attempt is made to address the design and development of a DW by applying and comparing different methodologies existing in the field. 展开更多
关键词 MULTIDIMENSIONAL DESIGN Paradigms data Warehouses Systematic mapPING
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Reconstructive Mapping from Sparsely-Sampled Groundwater Data Using Compressive Sensing
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作者 T.-W. Lee J. Y. Lee +2 位作者 J. E. Park H. Bellerova M. Raudensky 《Journal of Geographic Information System》 2021年第3期287-301,共15页
Compressive sensing is a powerful method for reconstruction of sparsely-sampled data, based on statistical optimization. It can be applied to a range of flow measurement and visualization data, and in this work we sho... Compressive sensing is a powerful method for reconstruction of sparsely-sampled data, based on statistical optimization. It can be applied to a range of flow measurement and visualization data, and in this work we show the usage in groundwater mapping. Due to scarcity of water in many regions of the world, including southwestern United States, monitoring and management of groundwater is of utmost importance. A complete mapping of groundwater is difficult since the monitored sites are far from one another, and thus the data sets are considered extremely “sparse”. To overcome this difficulty in complete mapping of groundwater, compressive sensing is an ideal tool, as it bypasses the classical Nyquist criterion. We show that compressive sensing can effectively be used for reconstructions of groundwater level maps, by validating against data. This approach can have an impact on geographical sensing and information, as effective monitoring and management are enabled without constructing numerous or expensive measurement sites for groundwater. 展开更多
关键词 Visualization data Compressive Sensing Reconstruction mapPING
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Data-Driven Microstructure and Microhardness Design in Additive Manufacturing Using a Self-Organizing Map 被引量:6
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作者 Zhengtao Gan Hengyang Li +5 位作者 Sarah J.Wolff Jennifer L.Bennett Gregory Hyatt Gregory J.Wagner Jian Cao Wing Kam Liu 《Engineering》 SCIE EI 2019年第4期730-735,共6页
To design microstructure and microhardness in the additive manufacturing(AM)of nickel(Ni)-based superalloys,the present work develops a novel data-driven approach that combines physics-based models,experimental measur... To design microstructure and microhardness in the additive manufacturing(AM)of nickel(Ni)-based superalloys,the present work develops a novel data-driven approach that combines physics-based models,experimental measurements,and a data-mining method.The simulation is based on a computational thermal-fluid dynamics(CtFD)model,which can obtain thermal behavior,solidification parameters such as cooling rate,and the dilution of solidified clad.Based on the computed thermal information,dendrite arm spacing and microhardness are estimated using well-tested mechanistic models.Experimental microstructure and microhardness are determined and compared with the simulated values for validation.To visualize process-structure-properties(PSPs)linkages,the simulation and experimental datasets are input to a data-mining model-a self-organizing map(SOM).The design windows of the process parameters under multiple objectives can be obtained from the visualized maps.The proposed approaches can be utilized in AM and other data-intensive processes.Data-driven linkages between process,structure,and properties have the potential to benefit online process monitoring control in order to derive an ideal microstructure and mechanical properties. 展开更多
关键词 Additive manufacturing data science MULTIPHYSICS modeling SELF-ORGANIZING map MICROSTRUCTURE MICROHARDNESS NI-BASED SUPERALLOY
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Mapping winter wheat using phenological feature of peak before winter on the North China Plain based on time-series MODIS data 被引量:16
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作者 TAO Jian-bin WU Wen-bin +2 位作者 ZHOU Yong WANG Yu JIANG Yan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第2期348-359,共12页
By employing the unique phenological feature of winter wheat extracted from peak before winter (PBW) and the advantages of moderate resolution imaging spectroradiometer (MODIS) data with high temporal resolution a... By employing the unique phenological feature of winter wheat extracted from peak before winter (PBW) and the advantages of moderate resolution imaging spectroradiometer (MODIS) data with high temporal resolution and intermediate spatial resolution, a remote sensing-based model for mapping winter wheat on the North China Plain was built through integration with Landsat images and land-use data. First, a phenological window, PBW was drawn from time-series MODIS data. Next, feature extraction was performed for the PBW to reduce feature dimension and enhance its information. Finally, a regression model was built to model the relationship of the phenological feature and the sample data. The amount of information of the PBW was evaluated and compared with that of the main peak (MP). The relative precision of the mapping reached up to 92% in comparison to the Landsat sample data, and ranged between 87 and 96% in comparison to the statistical data. These results were sufficient to satisfy the accuracy requirements for winter wheat mapping at a large scale. Moreover, the proposed method has the ability to obtain the distribution information for winter wheat in an earlier period than previous studies. This study could throw light on the monitoring of winter wheat in China by using unique phenological feature of winter wheat. 展开更多
关键词 time-series MODIS data phenological feature peak before wintering winter wheat mapping
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Extending self-organizing maps for supervised classification of remotely sensed data 被引量:1
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作者 CHEN Yongliang 《Global Geology》 2009年第1期46-56,共11页
An extended self-organizing map for supervised classification is proposed in this paper.Unlike other traditional SOMs,the model has an input layer,a Kohonen layer,and an output layer.The number of neurons in the input... An extended self-organizing map for supervised classification is proposed in this paper.Unlike other traditional SOMs,the model has an input layer,a Kohonen layer,and an output layer.The number of neurons in the input layer depends on the dimensionality of input patterns.The number of neurons in the output layer equals the number of the desired classes.The number of neurons in the Kohonen layer may be a few to several thousands,which depends on the complexity of classification problems and the classification precision.Each training sample is expressed by a pair of vectors: an input vector and a class codebook vector.When a training sample is input into the model,Kohonen's competitive learning rule is applied to selecting the winning neuron from the Kohonen layer and the weight coefficients connecting all the neurons in the input layer with both the winning neuron and its neighbors in the Kohonen layer are modified to be closer to the input vector,and those connecting all the neurons around the winning neuron within a certain diameter in the Kohonen layer with all the neurons in the output layer are adjusted to be closer to the class codebook vector.If the number of training samples is sufficiently large and the learning epochs iterate enough times,the model will be able to serve as a supervised classifier.The model has been tentatively applied to the supervised classification of multispectral remotely sensed data.The author compared the performances of the extended SOM and BPN in remotely sensed data classification.The investigation manifests that the extended SOM is feasible for supervised classification. 展开更多
关键词 自组织特征映射 监督分类 遥感数据 竞争学习规则 连接权系数 输入向量 神经元 训练样本
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Utilization of Open Source Spatial Data for Landslide Susceptibility Mapping at Chittagong District of Bangladesh—An Appraisal for Disaster Risk Reduction and Mitigation Approach
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作者 Md. Ashraful Islam Sanzida Murshed +4 位作者 S. M. Mainul Kabir Atikul Haque Farazi Md. Yousuf Gazi Israt Jahan Syed Humayun Akhter 《International Journal of Geosciences》 2017年第4期577-598,共22页
Since creation of spatial data is a costly and time consuming process, researchers, in this domain, in most of the cases rely on open source spatial attributes for their specific purpose. Likewise, the present researc... Since creation of spatial data is a costly and time consuming process, researchers, in this domain, in most of the cases rely on open source spatial attributes for their specific purpose. Likewise, the present research aims at mapping landslide susceptibility at the metropolitan area of Chittagong district of Bangladesh utilizing obtainable open source spatial data from various web portals. In this regard, we targeted a study region where rainfall induced landslides reportedly causes causalities as well as property damage each year. In this study, however, we employed multi-criteria evaluation (MCE) technique i.e., heuristic, a knowledge driven approach based on expert opinions from various discipline for landslide susceptibility mapping combining nine causative factors—geomorphology, geology, land use/land cover (LULC), slope, aspect, plan curvature, drainage distance, relative relief and vegetation in geographic information system (GIS) environment. The final susceptibility map was devised into five hazard classes viz., very low, low, moderate, high, and very high, representing 22 km2 (13%), 90 km2 (53%);24 km2 (15%);22 km2 (13%) and 10 km2 (6%) areas respectively. This particular study might be beneficial to the local authorities and other stake-holders, concerned in disaster risk reduction and mitigation activities. Moreover this study can also be advantageous for risk sensitive land use planning in the study area. 展开更多
关键词 Susceptibility mapping Open Source Spatial data Heuristic Model Chittagong METROPOLITAN Area GEOGRAPHIC Information System (GIS) Disaster Risk Reduction
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基于MapGIS的林业地理信息栅格图像数据矢量化方法
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作者 陈和彦 张礼娜 巫金明 《林业调查规划》 2023年第3期101-103,共3页
在林业工作中,进行制图、评价和决策分析时,矢量数据是必不可少的数据源,但有时获得矢量数据必须从纸质介质上获得。通过扫描纸质图件,获得软件可以识别、处理的栅格图像数据,使用MapGIS矢量化功能结合使用ArcGIS软件进行数据处理,可以... 在林业工作中,进行制图、评价和决策分析时,矢量数据是必不可少的数据源,但有时获得矢量数据必须从纸质介质上获得。通过扫描纸质图件,获得软件可以识别、处理的栅格图像数据,使用MapGIS矢量化功能结合使用ArcGIS软件进行数据处理,可以方便、快捷和准确地获得矢量化数据。文章对这一过程进行了分析和论述。 展开更多
关键词 mapGIS 矢量化 林业制图 纸质图 栅格图像数据
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The Importance of Integrating Geological Mapping Information with Validated Assay Data for Generating Accurate Geological Wireframes in Orebody Modelling of Mineral Deposit in Mineral Resource Estimation: A Case Study in AngloGold Ashanti, Obuasi Mine
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作者 Joshua Wereko Opong Chiri G. Amedjoe +1 位作者 Andy Asante Matthew Coffie Wilson 《International Journal of Geosciences》 2022年第6期426-437,共12页
The basis of accurate mineral resource estimates is to have a geological model which replicates the nature and style of the orebody. Key inputs into the generation of a good geological model are the sample data and ma... The basis of accurate mineral resource estimates is to have a geological model which replicates the nature and style of the orebody. Key inputs into the generation of a good geological model are the sample data and mapping information. The Obuasi Mine sample data with a lot of legacy issues were subjected to a robust validation process and integrated with mapping information to generate an accurate geological orebody model for mineral resource estimation in Block 8 Lower. Validation of the sample data focused on replacing missing collar coordinates, missing assays, and correcting magnetic declination that was used to convert the downhole surveys from true to magnetic, fix missing lithology and finally assign confidence numbers to all the sample data. The missing coordinates which were replaced ensured that the sample data plotted at their correct location in space as intended from the planning stage. Magnetic declination data, which was maintained constant throughout all the years even though it changes every year, was also corrected in the validation project. The corrected magnetic declination ensured that the drillholes were plotted on their accurate trajectory as per the planned azimuth and also reflected the true position of the intercepted mineralized fissure(s) which was previously not the case and marked a major blot in the modelling of the Obuasi orebody. The incorporation of mapped data with the validated sample data in the wireframes resulted in a better interpretation of the orebody. The updated mineral resource generated by domaining quartz from the sulphides and compared with the old resource showed that the sulphide tonnes in the old resource estimates were overestimated by 1% and the grade overestimated by 8.5%. 展开更多
关键词 Mineral Resource Estimation Geological Models Sample data Validation Assay data Geological mapping
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