期刊文献+
共找到9,985篇文章
< 1 2 250 >
每页显示 20 50 100
A Deep-Learning-Based Method for Interpreting Distribution and Difference Knowledge from Raster Topographic Maps 被引量:1
1
作者 PAN Yalan TI Peng +1 位作者 LI Mingyao LI Zhilin 《Journal of Geodesy and Geoinformation Science》 2025年第2期21-36,共16页
Topographic maps,as essential tools and sources of information for geographic research,contain precise spatial locations and rich map features,and they illustrate spatio-temporal information on the distribution and di... Topographic maps,as essential tools and sources of information for geographic research,contain precise spatial locations and rich map features,and they illustrate spatio-temporal information on the distribution and differences of various surface features.Currently,topographic maps are mainly stored in raster and vector formats.Extraction of the spatio-temporal knowledge in the maps—such as spatial distribution patterns,feature relationships,and dynamic evolution—still primarily relies on manual interpretation.However,manual interpretation is time-consuming and laborious,especially for large-scale,long-term map knowledge extraction and application.With the development of artificial intelligence technology,it is possible to improve the automation level of map knowledge interpretation.Therefore,the present study proposes an automatic interpretation method for raster topographic map knowledge based on deep learning.To address the limitations of current data-driven intelligent technology in learning map spatial relations and cognitive logic,we establish a formal description of map knowledge by mapping the relationship between map knowledge and features,thereby ensuring interpretation accuracy.Subsequently,deep learning techniques are employed to extract map features automatically,and the spatio-temporal knowledge is constructed by combining formal descriptions of geographic feature knowledge.Validation experiments demonstrate that the proposed method effectively achieves automatic interpretation of spatio-temporal knowledge of geographic features in maps,with an accuracy exceeding 80%.The findings of the present study contribute to machine understanding of spatio-temporal differences in map knowledge and advances the intelligent interpretation and utilization of cartographic information. 展开更多
关键词 raster topographic maps geographic feature knowledge intelligent interpretation deep learning
在线阅读 下载PDF
基于素养导向理念的大学生MAPS体育教学策略创新研究
2
作者 秦永 《体育科技》 2025年第2期104-106,共3页
《关于强化学校体育促进学生身心健康全面发展的意见》明确将提高学生的体育素养上升至国家层面。素养导向下的体育教学旨在培养个体具备动机、信心、身体能力、知识和理解力,致力于将有目的的身体活动应用在日常生活之中。通过对相关... 《关于强化学校体育促进学生身心健康全面发展的意见》明确将提高学生的体育素养上升至国家层面。素养导向下的体育教学旨在培养个体具备动机、信心、身体能力、知识和理解力,致力于将有目的的身体活动应用在日常生活之中。通过对相关理论与文献探讨,提出素养导向下大学生体育课堂教学的重点,以逻辑分析法深入剖析MAPS教学法所囊括的心智绘图、提问策略、口头发表和同侪鹰架四个教学策略,佐以大学生竞争型阵地攻守的篮球教学设计为例,希冀为深化改革高校公共体育课程和实施素养导向体育教学规划提供参考。研究发现,首先,将MAPS教学法融入到以素养为导向的大学生体育选项的技战术课程,能够有效地协助学生在战术与策略运用方面进行具体分析,透过心智绘图比较与其他组别的优劣势,找到应对方法;其次,通过教师引导提问,让学生更加清晰战术策略,以同侪发问讨论的形式对本组成果进行口头汇报;最后,以分组角色且委派不同学习任务,以达到提升学生身体素养所具备的认知、理解与运动技能,进而提高学生同侪鹰架的学习动机与成效。研究建议:(1)教师在建立概念与分析技战术策略时,秉承素养导向的理念,选用MAPS教学法,可有效帮助学生达成教学大纲的体育素养的翻转学习,迈向全人教育发展之路;(2)教学革新或课程改革应采用更为严谨的实证性教学实验研究,以构建出多元化、多项目群的身体素养导向的MAPS教学模式。 展开更多
关键词 身体素养 maps教学法 体育教学 课程设计
在线阅读 下载PDF
Exploring the Effects of Background Image Complexity and Map Symbol Load on the Usability of Image-maps 被引量:1
3
作者 PENG Qian XIA Yuxin QIU Zeren 《Journal of Geodesy and Geoinformation Science》 2025年第2期5-20,共16页
Image-maps,a hybrid design with satellite images as background and map symbols uploaded,aim to combine the advantages of maps’high interpretation efficiency and satellite images’realism.The usability of image-maps i... Image-maps,a hybrid design with satellite images as background and map symbols uploaded,aim to combine the advantages of maps’high interpretation efficiency and satellite images’realism.The usability of image-maps is influenced by the representations of background images and map symbols.Many researchers explored the optimizations for background images and symbolization techniques for symbols to reduce the complexity of image-maps and improve the usability.However,little literature was found for the optimum amount of symbol loading.This study focuses on the effects of background image complexity and map symbol load on the usability(i.e.,effectiveness and efficiency)of image-maps.Experiments were conducted by user studies via eye-tracking equipment and an online questionnaire survey.Experimental data sets included image-maps with ten levels of map symbol load in ten areas.Forty volunteers took part in the target searching experiments.It has been found that the usability,i.e.,average time viewed(efficiency)and average revisits(effectiveness)of targets recorded,is influenced by the complexity of background images,a peak exists for optimum symbol load for an image-map.The optimum levels for symbol load for different image-maps also have a peak when the complexity of the background image/image map increases.The complexity of background images serves as a guideline for optimum map symbol load in image-map design.This study enhanced user experience by optimizing visual clarity and managing cognitive load.Understanding how these factors interact can help create adaptive maps that maintain clarity and usability,guiding AI algorithms to adjust symbol density based on user context.This research establishes the practices for map design,making cartographic tools more innovative and more user-centric. 展开更多
关键词 remote sensing image map point label complexity
在线阅读 下载PDF
Microstructure Homogenization Control of GH4706 Alloy by Hot Deformation Maps
4
作者 Zheng Deyu Xia Yufeng Zhou Jie 《稀有金属材料与工程》 北大核心 2025年第12期3000-3009,共10页
Hot compression tests for GH4706 alloy were performed at a true strain of 1.2 within the temperature range of 950-1150℃ and the strain rate range of 0.001-1 s^(-1).The optimal hot deformation temperature and strain r... Hot compression tests for GH4706 alloy were performed at a true strain of 1.2 within the temperature range of 950-1150℃ and the strain rate range of 0.001-1 s^(-1).The optimal hot deformation temperature and strain rate range were determined using nephogram maps of dynamic recrystallization fraction,average grain size,and grain distribution standard deviation.Processing maps at true strains from 0.4 to 0.9 were generated based on flow stress curves to identify the strain corresponding to optimal microstructure homogenization efficiency at various temperatures and strain rates.Results show that within the optimal parameter range,under the conditions of 1150℃ and 0.01 s^(-1),the true strain of about 0.6 results in the optimal microstructure homogenization efficiency.The grain orientation spread maps obtained from the experiment also confirms this conclusion.This study provides an effective method for microstructure homogenization control of GH4706 alloy and an effective reference for the minimum strain threshold of the local part of the forging in engineering. 展开更多
关键词 GH4706 alloy dynamic recrystallization MICROSTRUCTURE homogenization efficiency processing map
原文传递
Single Qubit Quantum Logistic-Sine XYZ-Rotation Maps:An Ultra-Wide Range Dynamics for Image Encryption
5
作者 De Rosal Ignatius Moses Setiadi T.Sutojo +4 位作者 Supriadi Rustad Muhamad Akrom Sudipta Kr Ghosal Minh T.Nguyen Arnold Adimabua Ojugo 《Computers, Materials & Continua》 2025年第5期2161-2188,共28页
Data security has become a growing priority due to the increasing frequency of cyber-attacks,necessitating the development of more advanced encryption algorithms.This paper introduces Single Qubit Quantum Logistic-Sin... Data security has become a growing priority due to the increasing frequency of cyber-attacks,necessitating the development of more advanced encryption algorithms.This paper introduces Single Qubit Quantum Logistic-Sine XYZ-Rotation Maps(SQQLSR),a quantum-based chaos map designed to generate one-dimensional chaotic sequences with an ultra-wide parameter range.The proposed model leverages quantum superposition using Hadamard gates and quantum rotations along the X,Y,and Z axes to enhance randomness.Extensive numerical experiments validate the effectiveness of SQQLSR.The proposed method achieves a maximum Lyapunov exponent(LE)of≈55.265,surpassing traditional chaotic maps in unpredictability.The bifurcation analysis confirms a uniform chaotic distribution,eliminating periodic windows and ensuring higher randomness.The system also generates an expanded key space exceeding 10^(40),enhancing security against brute-force attacks.Additionally,SQQLSR is applied to image encryption using a simple three-layer encryption scheme combining permutation and substitution techniques.This approach is intentionally designed to highlight the impact of SQQLSR-generated chaotic sequences rather than relying on a complex encryption algorithm.Theencryption method achieves an average entropy of 7.9994,NPCR above 99.6%,and UACI within 32.8%–33.8%,confirming its strong randomness and sensitivity to minor modifications.The robustness tests against noise,cropping,and JPEG compression demonstrate its resistance to statistical and differential attacks.Additionally,the decryption process ensures perfect image reconstruction with an infinite PSNR value,proving the algorithm’s reliability.These results highlight SQQLSR’s potential as a lightweight yet highly secure encryption mechanism suitable for quantum cryptography and secure communications. 展开更多
关键词 Single qubit quantumchaotic quantumchaotic map quantumimage encryption quantumlogistic map quantum sine map
在线阅读 下载PDF
Use of supervised and unsupervised approaches to make zonal application maps for variable-rate application of crop growth regulators in commercial cotton fields
6
作者 ANDREA Maria C.da S. OLIVEIRA Cristiano F.de +7 位作者 MOTA Fabrícia C.M. SANTOS Rafael C.dos RODRIGUES JUNIOR Edilson F. BIANCHI Lucas M. OLIVEIRA Rodrigo S.de GOUVEIA Caio M.de BARBOSA Victor G.S. BISPO E SILVA Marco A. 《Journal of Cotton Research》 2025年第1期1-20,共20页
Background Zonal application maps are designed to represent field variability using key variables that can be translated into tailored management practices.For cotton,zonal maps for crop growth regulator(CGR)applicati... Background Zonal application maps are designed to represent field variability using key variables that can be translated into tailored management practices.For cotton,zonal maps for crop growth regulator(CGR)applications under variable-rate(VR)strategies are commonly based exclusively on vegetation indices(VIs)variability.However,VIs often saturate in dense crop vegetation areas,limiting their effectiveness in distinguishing variability in crop growth.This study aimed to compare unsupervised framework(UF)and supervised framework(SUF)approaches for generat-ing zonal application maps for CGR under VR conditions.During 2022-2023 agricultural seasons,an UF was employed to generate zonal maps based on locally collected field data on plant height of cotton,satellite imagery,soil texture,and phenology data.Subsequently,a SUF(based on historical data between 2020-2021 to 2022-2023 agricultural seasons)was developed to predict plant height using remote sensing and phenology data,aiming to replicate same zonal maps but without relying on direct field measurements of plant height.Both approaches were tested in three fields and on two different dates per field.Results The predictive model for plant height of SUF performed well,as indicated by the model metrics.However,when comparing zonal application maps for specific field-date combinations,the predicted plant height exhibited lower variability compared with field measurements.This led to variable compatibility between SUF maps,which utilized the model predictions,and the UF maps,which were based on the real field data.Fields characterized by much pronounced soil texture variability yielded the highest compatibility between the zonal application maps produced by both SUF and UF approaches.This was predominantly due to the greater consistency in estimating plant development patterns within these heterogeneous field environments.While VR application approach can facilitate product savings during the application operation,other key factors must be considered.These include the availability of specialized machinery required for this type of applications,as well as the inherent operational costs associated with applying a single CGR product which differs from the typical uniform rate applications that often integrate multi-ple inputs.Conclusion Predictive modeling shows promise for assisting in the creation of zonal application maps for VR of CGR applications.However,the degree of agreement with the actual variability in crop growth found in the field should be evaluated on a field-by-field basis.The SUF approach,which is based on plant heigh prediction,demonstrated potential for supporting the development of zonal application maps for VR of CGR applications.However,the degree to which this approach aligns itself with the actual variability in crop growth observed in the field may vary,necessi-tating field-by-field evaluation. 展开更多
关键词 Cotton Site-specific management Crop growth regulator Unsupervised framework Supervised framework Zonal application maps
在线阅读 下载PDF
Erratum to:Hydrochemical characterization of surface waters in Northen Tehran:Integrating cluster-based techniques with Self-Organizing Maps
7
作者 Maryam SALIMI Hamid Reza NASSERY +2 位作者 Meysam VADIATI Prosun BHATTACHARYA Akram RAHBAR 《Journal of Mountain Science》 2025年第9期3527-3527,共1页
The title of the online version of the original article was revised.The title of the original article has been revised to:Hydrochemical characterization of surface waters in Northern Tehran:Integrating cluster-based t... The title of the online version of the original article was revised.The title of the original article has been revised to:Hydrochemical characterization of surface waters in Northern Tehran:Integrating cluster-based techniques with Self-Organizing Maps. 展开更多
关键词 northern tehran cluster based techniques characterization surface waters hydrochemical characterization surface waters self organizing maps
原文传递
Constructing regional mineral prospecting knowledge graph from GIS maps
8
作者 Jiawen Liu Yuxin Ye +2 位作者 Ziheng Li Zhezhe Xing Shuisheng Ye 《Artificial Intelligence in Geosciences》 2025年第2期384-397,共14页
Geographic Information System(GIS)layers contain both spatial precision and domain knowledge,making them valuable for mineral prospectivity analysis.This study proposes a task-oriented methodology to struct con-a mine... Geographic Information System(GIS)layers contain both spatial precision and domain knowledge,making them valuable for mineral prospectivity analysis.This study proposes a task-oriented methodology to struct con-a mineral prospecting knowledge graph directly from GIS maps.The framework integrates ontology construction,spatiotemporal semantic embedding,and triple confidence evaluation.Ontologies are built from GIS layers through terminology extraction and alignment with existing standards,while spatial and temporal semantics are encoded using GeoSPARQL and the Geological Time Ontology.Graph Convolutional Networks(GCN)combined with the TransE embedding model are then applied to assess triple plausibility.A case study in the Eastern Tianshan region of Xinjiang verifies the effectiveness of the proposed method through semantic evaluation and graph-theoretic analysis.Guided by GIS,ontology construction significantly enhances the semantic fidelity and structural robustness of the prospecting knowledge graph,providing relatively reliable support for subsequent reasoning and predictive studies. 展开更多
关键词 Prospecting prediction Knowledge graph Ontology engineering GIS maps
在线阅读 下载PDF
基于Self-Organizing Maps回归算法的黄河流域降水量空间预测研究
9
作者 刘文婷 白明照 李凤云 《陕西水利》 2025年第6期9-11,16,共4页
基于Self-Organizing Maps(SOM)回归算法,构建黄河流域降水量空间预测模型。利用2020年305个气象站点降水观测数据,结合海拔、坡度、坡向、NDVI等地理环境因子,通过网格搜索法优化SOM模型参数。结果表明,SOM模型成功捕捉了黄河流域降水... 基于Self-Organizing Maps(SOM)回归算法,构建黄河流域降水量空间预测模型。利用2020年305个气象站点降水观测数据,结合海拔、坡度、坡向、NDVI等地理环境因子,通过网格搜索法优化SOM模型参数。结果表明,SOM模型成功捕捉了黄河流域降水量空间异质性,预测精度较高(R2=0.83,RMSE=47.6 mm)。降水量呈现由东南向西北递减趋势,范围在135 mm~1171 mm之间,高值区(>900 mm)主要分布在东南部,中值区(500 mm~800 mm)位中部,低值区(<400 mm)集中在西北部。该研究可为降水量空间预测提供一种有效的新途径。 展开更多
关键词 Self-Organizing maps 降水量 黄河流域 空间预测
在线阅读 下载PDF
Comparing disaggregation approaches DSMART and PPD in disaggregating soil series maps
10
作者 Tahmid Huq EASHER Daniel SAURETTE +3 位作者 Brandon HEUNG Adam GILLESPIE Richard J.HECK Asim BISWAS 《Pedosphere》 2025年第2期387-404,共18页
Conventional soil maps(CSMs)often have multiple soil types within a single polygon,which hinders the ability of machine learning to accurately predict soils.Soil disaggregation approaches are commonly used to improve ... Conventional soil maps(CSMs)often have multiple soil types within a single polygon,which hinders the ability of machine learning to accurately predict soils.Soil disaggregation approaches are commonly used to improve the spatial and attribute precision of CSMs.The approach disaggregation and harmonization of soil map units through resampled classification trees(DSMART)is popular but computationally intensive,as it generates and assigns synthetic samples to soil series based on the areal coverage information of CSMs.Alternatively,the disaggregation approach pure polygon disaggregation(PPD)assigns soil series based solely on the proportions of soil series in pure polygons in CSMs.This study compared these two disaggregation approaches by applying them to a CSM of Middlesex County,Ontario,Canada.Four different sampling methods were used:two sampling designs,simple random sampling(SRS)and conditional Latin hypercube sampling(cLHS),with two sample sizes(83100 and 19420 samples per sampling plan),both based on an area-weighted approach.Two machine learning algorithms(MLAs),C5.0 decision tree(C5.0)and random forest(RF),were applied to the disaggregation approaches to compare the disaggregation accuracy.The accuracy assessment utilized a set of 500 validation points obtained from the Middlesex County soil survey report.The MLA C5.0(Kappa index=0.58–0.63)showed better performance than RF(Kappa index=0.53–0.54)based on the larger sample size,and PPD with C5.0 based on the larger sample size was the best-performing(Kappa index=0.63)approach.Based on the smaller sample size,both cLHS(Kappa index=0.41–0.48)and SRS(Kappa index=0.40–0.47)produced similar accuracy results.The disaggregation approach PPD exhibited lower processing capacity and time demands(1.62–5.93 h)while yielding maps with lower uncertainty as compared to DSMART(2.75–194.2 h).For CSMs predominantly composed of pure polygons,utilizing PPD for soil series disaggregation is a more efficient and rational choice.However,DSMART is the preferable approach for disaggregating soil series that lack pure polygon representations in the CSMs. 展开更多
关键词 conditioned Latin hypercube sampling conventional soil map machine learning algorithm processing capacity and time sample size simple random sampling soil map unit soil series disaggregation
原文传递
Large-scale modelling wind damage vulnerability through combination of high-resolution forest resources maps and ForestGALES
11
作者 Morgane Merlin Tommaso Locatelli +1 位作者 Barry Gardiner Rasmus Astrup 《Forest Ecosystems》 2025年第5期1021-1034,共14页
Assessing forest vulnerability to disturbances at a high spatial resolution and for regional and national scales has become attainable with the combination of remote sensing-derived high-resolution forest maps and mec... Assessing forest vulnerability to disturbances at a high spatial resolution and for regional and national scales has become attainable with the combination of remote sensing-derived high-resolution forest maps and mechanistic risk models. This study demonstrated large-scale and high-resolution modelling of wind damage vulnerability in Norway. The hybrid mechanistic wind damage model, ForestGALES, was adapted to map the critical wind speeds(CWS) of damage across Norway using a national forest attribute map at a 16 m × 16 m spatial resolution. P arametrization of the model for the Norwegian context was done using the literature and the National Forest Inventory data. This new parametrization of the model for Norwegian forests yielded estimates of CWS significantly different from the default parametrization. Both parametrizations fell short of providing acceptable discrimination of the damaged area following the storm of November 19, 2021 in the central southern region of Norway when using unadjusted CWS. After adjusting the CWS and the storm wind speeds by a constant factor, the Norwegian parametrization provided acceptable discrimination and was thus defined as suitable to use in future studies, despite the lack of field-and laboratory experiments to directly derive parameters for Norwegian forests. The windstorm event used for model validation in this study highlighted the challenges of predicting wind damage to forests in landscapes with complex topography. Future studies should focus on further developing ForestGALES and new datasets describing extreme wind climates to better represent the wind and tree interactions in complex topography, and predict the level of risk in order to develop local climate-smart forest management strategies. 展开更多
关键词 WIND Natural disturbance ForestGALES Damage probability Forest resource map
在线阅读 下载PDF
Channel Knowledge Maps for 6G Wireless Networks:Construction,Applications,and Future Challenges
12
作者 LIU Xingchen SUN Shu +2 位作者 TAO Meixia Aryan KAUSHIK YAN Hangsong 《ZTE Communications》 2025年第2期46-59,共14页
The advent of 6G wireless networks promises unprecedented connectivity,supporting ultra-high data rates,low latency,and massive device connectivity.However,these ambitious goals introduce significant challenges,partic... The advent of 6G wireless networks promises unprecedented connectivity,supporting ultra-high data rates,low latency,and massive device connectivity.However,these ambitious goals introduce significant challenges,particularly in channel estimation due to complex and dynamic propagation environments.This paper explores the concept of channel knowledge maps(CKMs)as a solution to these challenges.CKMs enable environment-aware communications by providing location-specific channel information,reducing reliance on real-time pilot measurements.We categorize CKM construction techniques into measurement-based,model-based,and hybrid methods,and examine their key applications in integrated sensing and communication(ISAC)systems,beamforming,trajectory optimization of unmanned aerial vehicles(UAVs),base station(BS)placement,and resource allocation.Furthermore,we discuss open challenges and propose future research directions to enhance the robustness,accuracy,and scalability of CKM-based systems in the evolving 6G landscape. 展开更多
关键词 channel knowledge map channel modeling wireless communication 6G
在线阅读 下载PDF
Knowledge Maps from Scientometric Review on Composite Marine Risers
13
作者 Chiemela Victor Amaechi Ahmed Reda +8 位作者 Salmia Binti Beddu Daud Bin Mohamed Agusril Syamsir Idris Ahmed Ja’e Bo Huang Chunguang Wang Xuanze Ju Jelson Cassavela Abiodun Kolawole Oyetunji 《Sustainable Marine Structures》 2025年第1期1-20,共20页
With the increasing exploration of oil and gas into deep waters,the necessity for material development increases for lighter conduits such as composite marine risers,in the oil and gas industry.To understand the resea... With the increasing exploration of oil and gas into deep waters,the necessity for material development increases for lighter conduits such as composite marine risers,in the oil and gas industry.To understand the research knowledge on this novel area,there is a need to have a bibliometric analysis on composite marine risers.A research methodology was developed whereby the data retrieval was from SCOPUS database from 1977–2023.Then,VOSviewer was used to visualize the knowledge maps.This study focuses on the progress made by conducting knowledge mapping and scientometric review on composite marine risers.This scientometric analysis on the subject shows current advances,geographical activities by countries,authorship records,collaborations,funders,affiiliations,co‑occurrences,and future research areas.It was observed that the research trends recorded the highest publication volume in the U.S.A.,but less cluster affiiliated,as it was followed by countries like the U.K.,China,Nigeria,Australia and Singapore.Also,thisfiield has more conference papers than journal papers due to the challenge of adaptability,acceptance,qualifiication,and application of composite marine risers in the marine industry.Hence,there is a need for more collaborations on composite marine risers and more funding to enhance the research trend. 展开更多
关键词 Composite Risers Marine Risers Marine Structure Scientometric Review Bibliometric Analysis Composite Material Knowledge Map
在线阅读 下载PDF
Hydrochemical characterization of surface waters in Northern Tehran: Integrating cluster-based techniques with Self-Organizing Maps
14
作者 Maryam SALIMI Hamid Reza NASSERY +2 位作者 Meysam VADIATI Prosun BHATTACHARYA Akram RAHBAR 《Journal of Mountain Science》 2025年第7期2370-2390,共21页
Water quality is a critical global issue,especially in urban and semi-urban regions where natural and anthropogenic factors significantly influence surface water systems.This study evaluates the hydrochemical characte... Water quality is a critical global issue,especially in urban and semi-urban regions where natural and anthropogenic factors significantly influence surface water systems.This study evaluates the hydrochemical characteristics of surface water in the North of Tehran Rivers(NTRs),an essential water resource in a rapidly urbanizing region,using advanced clustering techniques,including Hierarchical Clustering Analysis(HCA),Fuzzy CMeans(FCM),Genetic Algorithm Fuzzy C-Means(GAFCM),and Self-Organizing Map(SOM).The research aims to address the scientific challenge of understanding spatial and temporal variability in water quality,focusing on physicochemical parameters,hydrochemical facies,and contamination sources.Water samples from six rivers collected over four seasons in 2020 were analyzed and classified into distinct clusters based on their chemical composition,revealing significant seasonal and spatial differences.Results showed that FCM and GAFCM consistently categorized the NTRs into two clusters during winter and spring and three in summer and autumn.These findings were supported by HCA and SOM,which identified clusters corresponding to specific river segments and contamination levels.The primary hydrochemical processes identified were mineral dissolution and weathering,with calcite,dolomite,and aragonite significantly influencing water chemistry.Additionally,human activities,such as wastewater discharge,were shown to contribute to elevated sulfate,nitrate,and phosphate concentrations,further corroborated by microbial analyses.By integrating HCA,FCM,and GAFCM with an artificial neural network(ANN)-based clustering method(SOM),this study provides a robust framework for evaluating surface water quality.The findings,supported by Gibbs diagrams,Hounslow ion ratio,and saturation indices,highlight the dominance of rock weathering and human impacts in shaping the hydrochemical dynamics of the NTRs.These insights contribute to the scientific understanding of water quality dynamics and offer practical guidance for sustainable water resource management and environmental protection in developing urban areas. 展开更多
关键词 Hydrochemical characteristics Clustering techniques Contamination sources Tehran Rivers Self Organizing Map Surface water quality
原文传递
Vanishing theorems for f-CC harmonic maps with potential H into sub-Riemannian manifolds
15
作者 LI Jing HE Guo-qing ZHAO Pei-biao 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第4期802-817,共16页
In this paper,we introduce the notion of f-CC harmonic maps with potential H from a Riemannian manifold into sub-Riemannian manifolds,and achieve some vanishing theorems for f-CC harmonic maps with potential H via the... In this paper,we introduce the notion of f-CC harmonic maps with potential H from a Riemannian manifold into sub-Riemannian manifolds,and achieve some vanishing theorems for f-CC harmonic maps with potential H via the stress-energy tensor and the monotonicity formulas. 展开更多
关键词 f-CC harmonic map with potential stress energy tensor sub-Riemannian manifold
在线阅读 下载PDF
Improved SE-UNet network-based semantic segmentation and extraction of hidden geological significance in geological maps
16
作者 Kai Ma Jun-jie Liu +5 位作者 Si-qi Lu Ze-hua Huang Miao Tian Jun-yuan Deng Zhong Xie Qin-jun Qiu 《China Geology》 2025年第4期643-660,共18页
Automatic segmentation and recognition of content and element information in color geological map are of great significance for researchers to analyze the distribution of mineral resources and predict disaster informa... Automatic segmentation and recognition of content and element information in color geological map are of great significance for researchers to analyze the distribution of mineral resources and predict disaster information.This article focuses on color planar raster geological map(geological maps include planar geological maps,columnar maps,and profiles).While existing deep learning approaches are often used to segment general images,their performance is limited due to complex elements,diverse regional features,and complicated backgrounds for color geological map in the domain of geoscience.To address the issue,a color geological map segmentation model is proposed that combines the Felz clustering algorithm and an improved SE-UNet deep learning network(named GeoMSeg).Firstly,a symmetrical encoder-decoder structure backbone network based on UNet is constructed,and the channel attention mechanism SENet has been incorporated to augment the network’s capacity for feature representation,enabling the model to purposefully extract map information.The SE-UNet network is employed for feature extraction from the geological map and obtain coarse segmentation results.Secondly,the Felz clustering algorithm is used for super pixel pre-segmentation of geological maps.The coarse segmentation results are refined and modified based on the super pixel pre-segmentation results to obtain the final segmentation results.This study applies GeoMSeg to the constructed dataset,and the experimental results show that the algorithm proposed in this paper has superior performance compared to other mainstream map segmentation models,with an accuracy of 91.89%and a MIoU of 71.91%. 展开更多
关键词 Geological map UNet model Image segmentation Semantic segmentation Pixel pre-segmentation Clustering algorithm Attention mechanism Deep learning Artificial intelligence Geological survey engineering
在线阅读 下载PDF
从Google Maps看我国全球化地理信息服务面临的挑战和对策 被引量:26
17
作者 符海月 赵军 李满春 《地理与地理信息科学》 CSCD 北大核心 2006年第2期I0001-I0003,共3页
以Google Maps为代表的地图服务的推出预示着全球化地理信息服务的开始。IT领域竞争市场的形成、高分辨率卫星影像的应用及Web地理信息服务开发平台的实现是全球化地理信息服务的主要趋势。面对全球化地理信息服务发展机遇,我国面临地... 以Google Maps为代表的地图服务的推出预示着全球化地理信息服务的开始。IT领域竞争市场的形成、高分辨率卫星影像的应用及Web地理信息服务开发平台的实现是全球化地理信息服务的主要趋势。面对全球化地理信息服务发展机遇,我国面临地理数据库建设、地理信息市场社会化与地理信息区域均衡发展的严峻挑战。在分析我国地理信息服务面临挑战的基础上,从数字化建设、地理信息服务市场培育、卫星遥感技术商业化发展3方面提出我国地理信息服务发展的对策与建议。 展开更多
关键词 地理信息服务 全球信息化 GOOGLE maps 地理信息共享 地理信息市场
在线阅读 下载PDF
基于Google Maps API的烟草种质资源WebGIS开发研究 被引量:7
18
作者 任民 张兴伟 +2 位作者 王志德 刘艳华 牟建民 《植物遗传资源学报》 CAS CSCD 北大核心 2010年第5期522-526,共5页
采用B/S架构,应用ASP.NET技术开发了烟草种质资源WebGIS。该系统采用Google Maps API作为地图服务,其数据库采用Microsoft SQL Server,服务器端程序应用C++语言开发,浏览器端基于XHTML+JavaScript。该系统对地图操作和种质资源查询进行... 采用B/S架构,应用ASP.NET技术开发了烟草种质资源WebGIS。该系统采用Google Maps API作为地图服务,其数据库采用Microsoft SQL Server,服务器端程序应用C++语言开发,浏览器端基于XHTML+JavaScript。该系统对地图操作和种质资源查询进行了整合,用户可通过4种类型5种比例的地图,选择感兴趣的区域和范围。其地图标注和地址解析功能直观地展现了种质资源的地理分布状况,以及种质资源所在位置的地址名称和经纬度等。另外,用户还可通过WebGIS的查询功能获得种质资源的详细数据信息。因此,本研究开发的烟草种质资源WebGIS为种质资源的研究与利用提供了新的技术和策略。 展开更多
关键词 GOOGLE maps API WEBGIS 种质资源 烟草
原文传递
基于Google Maps的农业机械作业轨迹监测系统 被引量:11
19
作者 史国滨 王熙 庄卫东 《农业机械学报》 EI CAS CSCD 北大核心 2012年第11期231-236,共6页
为满足现代农业机械管理需要,实现农业机械作业调度与实时监控,运用GPS、GPRS和Google Maps技术进行有机集成,构建了农业机械作业轨迹监测系统。该系统采用单片机整合GPS模块、GPRS模块实现车载GPS数据无线远程回传,通过Google Maps AP... 为满足现代农业机械管理需要,实现农业机械作业调度与实时监控,运用GPS、GPRS和Google Maps技术进行有机集成,构建了农业机械作业轨迹监测系统。该系统采用单片机整合GPS模块、GPRS模块实现车载GPS数据无线远程回传,通过Google Maps API构建Web GIS系统,采用ASP.NET实现农业机械田间作业管理;以Web Service技术及Ajax技术实现作业轨迹回放、作业实时定位及长度、面积测量等功能。 展开更多
关键词 农业机械 作业轨迹 监测 GOOGLE maps WEB GIS
在线阅读 下载PDF
Google Maps API技术在移动终端上的GIS应用 被引量:15
20
作者 周鹏 陈红顺 尹菲 《测绘通报》 CSCD 北大核心 2012年第3期95-96,108,共3页
综合应用Google Maps API、Android、数据库、服务器技术等集成方法,开发了Android端应用程序,实现了实时数据(包括GPS坐标等数据)的校园GIS的应用。
关键词 地图服务 GOOGLE maps API Android 移动GIS
原文传递
上一页 1 2 250 下一页 到第
使用帮助 返回顶部