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Risk Prediction of Tunnel Water and Mud Inrush Based on Decision-Level Fusion of Multisource Data
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作者 Shi-shu Zhang Peng Wang +4 位作者 Hua-bo Xiao Huai-bing Wang Yi-guo Xue Wei-dong Chen Kai Zhang 《Applied Geophysics》 2025年第2期472-487,559,560,共18页
This paper addresses the accuracy and timeliness limitations of traditional comprehensive prediction methods by proposing an approach of decision-level fusion of multisource data.A risk prediction indicator system was... This paper addresses the accuracy and timeliness limitations of traditional comprehensive prediction methods by proposing an approach of decision-level fusion of multisource data.A risk prediction indicator system was established for water and mud inrush in tunnels by analyzing advanced prediction data for specifi c tunnel segments.Additionally,the indicator weights were determined using the analytic hierarchy process combined with the Huber weighting method.Subsequently,a multisource data decision-layer fusion algorithm was utilized to generate fused imaging results for tunnel water and mud inrush risk predictions.Meanwhile,risk analysis was performed for different tunnel sections to achieve spatial and temporal complementarity within the indicator system and optimize redundant information.Finally,model feasibility was validated using the CZ Project Sejila Mountain Tunnel segment as a case study,yielding favorable risk prediction results and enabling effi cient information fusion and support for construction decision-making. 展开更多
关键词 Tunnel water and mud inrush prediction methods risk indicators multisource data decision-level fusion
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Multisource Data Fusion Using MLP for Human Activity Recognition
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作者 Sujittra Sarakon Wansuree Massagram Kreangsak Tamee 《Computers, Materials & Continua》 2025年第2期2109-2136,共28页
This research investigates the application of multisource data fusion using a Multi-Layer Perceptron (MLP) for Human Activity Recognition (HAR). The study integrates four distinct open-source datasets—WISDM, DaLiAc, ... This research investigates the application of multisource data fusion using a Multi-Layer Perceptron (MLP) for Human Activity Recognition (HAR). The study integrates four distinct open-source datasets—WISDM, DaLiAc, MotionSense, and PAMAP2—to develop a generalized MLP model for classifying six human activities. Performance analysis of the fused model for each dataset reveals accuracy rates of 95.83 for WISDM, 97 for DaLiAc, 94.65 for MotionSense, and 98.54 for PAMAP2. A comparative evaluation was conducted between the fused MLP model and the individual dataset models, with the latter tested on separate validation sets. The results indicate that the MLP model, trained on the fused dataset, exhibits superior performance relative to the models trained on individual datasets. This finding suggests that multisource data fusion significantly enhances the generalization and accuracy of HAR systems. The improved performance underscores the potential of integrating diverse data sources to create more robust and comprehensive models for activity recognition. 展开更多
关键词 multisource data fusion human activity recognition multi-layer perceptron(MLP) artificial intelligent
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Integrating multisource RS data and GIS techniques to assist the evaluation of resource-environment carrying capacity in karst mountainous area 被引量:9
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作者 PU Jun-wei ZHAO Xiao-qing +4 位作者 MIAO Pei-pei LI Si-nan TAN Kun WANG Qian TANG Wei 《Journal of Mountain Science》 SCIE CSCD 2020年第10期2528-2547,共20页
The karst mountainous area is an ecologically fragile region with prominent humanland contradictions.The resource-environment carrying capacity(RECC)of this region needs to be further clarified.The development of remo... The karst mountainous area is an ecologically fragile region with prominent humanland contradictions.The resource-environment carrying capacity(RECC)of this region needs to be further clarified.The development of remote sensing(RS)and geographic information system(GIS)provides data sources and processing platform for RECC monitoring.This study analyzed and established the evaluation index system of RECC by considering particularity in the karst mountainous area of Southwest China;processed multisource RS data(Sentinel-2,Aster-DEM and Landsat-8)to extract the spatial distributions of nine key indexes by GIS techniques(information classification,overlay analysis and raster calculation);proposed the methods of index integration and fuzzy comprehensive evaluation of the RECC by GIS;and took a typical area,Guangnan County in Yunnan Province of China,as an experimental area to explore the effectiveness of the indexes and methods.The results showed that:(1)The important indexes affecting the RECC of karst mountainous area are water resources,tourism resources,position resources,geographical environment and soil erosion environment.(2)Data on cultivated land,construction land,minerals,transportation,water conservancy,ecosystem services,topography,soil erosion and rocky desertification can be obtained from RS data.GIS techniques integrate the information into the RECC results.The data extraction and processing methods are feasible on evaluating RECC.(3)The RECC of Guangnan County was in the mid-carrying level in 2018.The midcarrying and low-carrying levels were the main types,accounting for more than 80.00%of the total study area.The areas with high carrying capacity were mainly distributed in the northern regions of the northwest-southeast line of the county,and other areas have a low carrying capacity comparatively.The coordination between regional resource-environment status and socioeconomic development is the key to improve RECC.This study explores the evaluation index system of RECC in karst mountainous area and the application of multisource RS data and GIS techniques in the comprehensive evaluation.The methods can be applied in related fields to provide suggestions for data/information extraction and integration,and sustainable development. 展开更多
关键词 Carrying capacity multisource RS data GIS techniques Evaluation index system Data Integration Karst mountainous area Fuzzy comprehensive evaluation method
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Insights into multisource sludge distributed in the Yangtze River basin, China: Characteristics,correlation, treatment and disposal 被引量:2
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作者 Yiqun Guo Hui Gong +7 位作者 Wenjing Shi Ning Fang Yaqin Tan Weiqi Zhou Jialiang Huang Lingling Dai Xiaohu Dai Yali Guo 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2023年第4期321-332,共12页
Sludge is the by-product of wastewater treatment process. Multisource sludge can be defined as sludge from different sources. Based on the sludge properties of five typical cities in the Yangtze River basin, including... Sludge is the by-product of wastewater treatment process. Multisource sludge can be defined as sludge from different sources. Based on the sludge properties of five typical cities in the Yangtze River basin, including Jiujiang, Wuhu, Lu’an, Zhenjiang and Wuhan, this study investigated and summarized the characteristic variations and distribution differences of multiple indicators and substances from municipal sludge, dredged sludge, and river and lake sediments. The results demonstrated pH of multisource sludge was relatively stable in the neutral range. Organic matter and water content among municipal sludge were high and varied considerably between different wastewater treatment plants. Dredged sludge had an obviously higher sand content and wider particle distribution, which could be considered for graded utilization depending on its size. The nutrients composition of river and lake sediments was usually stable and special, with lower nitrogen and phosphorus content but higher potassium levels. The sources of heavy metals and persistent organic pollutants in multisource sludge were correlated, generally much higher among municipal sludge than dredged sludge and river and lake sediments, which were the most important limitation for final land utilization. Despite various properties of multisource sludge, the final fate and destination have some overall similarities, which need to be supplemented and improved by standards and laws. The study provided a preliminary analysis of suitable technical routes for municipal sludge, dredged sludge, river and lake sediments based on their different characteristics respectively, which was of great significance for multisource sludge co-treatment and disposal in the future of China. 展开更多
关键词 multisource sludge Basic characteristics Potential correlation Treatment and disposal Heavy metals Persistent organic pollutants
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Construction and implementation of multisource spatial data management system of China's coastal zone and offshore 被引量:3
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作者 DUYunyan WANGJinggui +1 位作者 WANGZuoyong YANGXiaomei 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2004年第1期97-108,共12页
To meet the increasing demand of national spatial database infrastructure construction and application, a concept model of China's coastal zone scientific data platform is established based on the information feat... To meet the increasing demand of national spatial database infrastructure construction and application, a concept model of China's coastal zone scientific data platform is established based on the information feature analysis of a compound dataset, consisting of remote sensing data and conventional data. Based on this concept model, the detailed logical database structure and the storage strategy of remote sensing data and their metadata using ArcSDE are designed. The complicated technology of multisources data combination in this research is crucial to the future coastal zone and offshore database construction and practical running, which will provide intelligent information analysis and technological service for coastal zone and offshore investigation, research, development and management. 展开更多
关键词 China's coastal zone multisources data concept models information system technological platform
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Comprehensive drought monitoring in Yunnan Province, China using multisource remote sensing data 被引量:2
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作者 WANG Jin-liang YU Yuan-he 《Journal of Mountain Science》 SCIE CSCD 2021年第6期1537-1549,共13页
Development of drought monitoring techniques is important for understanding and mitigating droughts and for rational agricultural management. This study used data from multiple sources, including MOD13 A3, TRMM 3 B43,... Development of drought monitoring techniques is important for understanding and mitigating droughts and for rational agricultural management. This study used data from multiple sources, including MOD13 A3, TRMM 3 B43, and SRTMDEM, for Yunnan Province, China from 2009 to 2018 to calculate the tropical rainfall condition index(TRCI), vegetation condition index(VCI), temperature condition index(TCI), and elevation factors. Principal component analysis(PCA) and analytic hierarchy process(AHP) were used to construct comprehensive drought monitoring models for Yunnan Province. The reliability of the models was verified, following which the drought situation in Yunnan Province for the past ten years was analysed. The results showed that:(1) The comprehensive drought index(CDI) had a high correlation with the standardized precipitation index, standardized precipitation evapotranspiration index, temperature vegetation dryness index, and CLDAS(China Meteorological Administration land data assimilation system), indicating that the CDI was a strong indicator of drought through meteorological, remote sensing and soil moisture monitoring.(2) The droughts from 2009 to 2018 showed generally consistent spatiotemporal changes. Droughts occurred in most parts of the province, with an average drought frequency of 29% and four droughtprone centres.(3) Monthly drought coverage during 2009 to 2014 exceeded that over 2015 to 2018. January had the largest average drought coverage over the study period(61.92%). Droughts at most stations during the remaining months except for October exhibited a weakening trend(slope > 0). The CDI provides a novel approach for drought monitoring in areas with complex terrain such as Yunnan Province. 展开更多
关键词 multisource data Comprehensive drought index(CDI) Standardized precipitation index(SPI) Standardized precipitation evapotranspiration index(SPEI) Temperature vegetation dryness index(TVDI) Yunnan Province China
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RANDOM SETS: A UNIFIED FRAMEWORK FOR MULTISOURCE INFORMATION FUSION 被引量:3
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作者 Xu Xiaobin Wen Chenglin 《Journal of Electronics(China)》 2009年第6期723-730,共8页
The more diverse the ways and means of information acquisition are,the more complex and various the types of information are. The qualities of available information are usually uncertain,vague,imprecise,incomplete,and... The more diverse the ways and means of information acquisition are,the more complex and various the types of information are. The qualities of available information are usually uncertain,vague,imprecise,incomplete,and so on. However,the information is modeled and fused traditionally in particular,name some of the known theories: evidential,fuzzy sets,possibilistic,rough sets or conditional events,etc. For several years,researchers have explored the unification of theories enabling the fusion of multisource information and have finally considered random set theory as a powerful mathematical tool. This paper attempts to overall review the close relationships between random set theory and other theories,and introduce recent research results which present how different types of information can be dealt with in this unified framework. Finally,some possible future directions are discussed. 展开更多
关键词 multisource information fusion Random set theory Imperfect information
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Effects of periodically varying codes on separation of multisource blended data 被引量:1
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作者 Jiao Meng-Yao Hu Tian-Yue +4 位作者 Liu Yang Yu Zhen-Zhen Liang Shang-Lin Liu Li-Chao Ji-Wei 《Applied Geophysics》 SCIE CSCD 2021年第3期331-344,432,共15页
Current exploration needs are satisfied by multisource technology,which offers low cost,high efficiency,and high precision.The delay time,which determines the separation effects of the multisource blended data,is one ... Current exploration needs are satisfied by multisource technology,which offers low cost,high efficiency,and high precision.The delay time,which determines the separation effects of the multisource blended data,is one of the most crucial parameters in the acquisition and separation of multisource data.This study uses the deblending method of multisource data based on a periodically varying cosine code and analyses the effects of the two parameters,namely,the period amplitude and period length,used in this method on the separation of the multisource blended data.Meanwhile,the obtained coherence data is used to prove the correlation between the separation of multisource data and the two parameters.Examples of synthetic and field data are adopted to demonstrate that from a qualitative perspective,increasing the amplitude of the periodic code improves the separation effect within a reasonable delay time range.When the period length varies in a suitable range,the secondary noise becomes relatively incoherent,resulting in the separation result with a higher signal-to-noise ratio(SNR).From a quantitative perspective,the significant values(Sig.)of the period amplitude and length on the SNRs are less than 0.05,verifying the correlation between the separation of multisource data and the two parameters. 展开更多
关键词 multisource technology periodically varying cosine code period amplitude period length correlation
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Slope displacement prediction based on multisource domain transfer learning for insufficient sample data 被引量:1
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作者 Zheng Hai-Qing Hu Lin-Ni +2 位作者 Sun Xiao-Yun Zhang Yu Jin Shen-Yi 《Applied Geophysics》 SCIE CSCD 2024年第3期496-504,618,共10页
Accurate displacement prediction is critical for the early warning of landslides.The complexity of the coupling relationship between multiple influencing factors and displacement makes the accurate prediction of displ... Accurate displacement prediction is critical for the early warning of landslides.The complexity of the coupling relationship between multiple influencing factors and displacement makes the accurate prediction of displacement difficult.Moreover,in engineering practice,insufficient monitoring data limit the performance of prediction models.To alleviate this problem,a displacement prediction method based on multisource domain transfer learning,which helps accurately predict data in the target domain through the knowledge of one or more source domains,is proposed.First,an optimized variational mode decomposition model based on the minimum sample entropy is used to decompose the cumulative displacement into the trend,periodic,and stochastic components.The trend component is predicted by an autoregressive model,and the periodic component is predicted by the long short-term memory.For the stochastic component,because it is affected by uncertainties,it is predicted by a combination of a Wasserstein generative adversarial network and multisource domain transfer learning for improved prediction accuracy.Considering a real mine slope as a case study,the proposed prediction method was validated.Therefore,this study provides new insights that can be applied to scenarios lacking sample data. 展开更多
关键词 slope displacement multisource domain transfer learning(MDTL) variational mode decomposition(VMD) generative adversarial network(GAN) Wasserstein-GAN
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A Multisource Contour Matching Method Considering the Similarity of Geometric Features 被引量:8
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作者 Wenyue GUO Anzhu YU +4 位作者 Qun SUN Shaomei LI Qing XU Bowei WEN Yuanfu LI 《Journal of Geodesy and Geoinformation Science》 2020年第3期76-87,共12页
The existing multi-source contour matching studies have focused on the matching methods with consideration of topological relations and similarity measurement based on spatial Euclidean distance,while it is lack of ta... The existing multi-source contour matching studies have focused on the matching methods with consideration of topological relations and similarity measurement based on spatial Euclidean distance,while it is lack of taking the contour geometric features into account,which may lead to mismatching in map boundaries and areas with intensive contours or extreme terrain changes.In light of this,it is put forward that a matching strategy from coarse to precious based on the contour geometric features.The proposed matching strategy can be described as follows.Firstly,the point sequence is converted to feature sequence according to a feature descriptive function based on curvature and angle of normal vector.Then the level of similarity among multi-source contours is calculated by using the longest common subsequence solution.Accordingly,the identical contours could be matched based on the above calculated results.In the experiment for the proposed method,the reliability and efficiency of the matching method are verified using simulative datasets and real datasets respectively.It has been proved that the proposed contour matching strategy has a high matching precision and good applicability. 展开更多
关键词 multisource contour matching geometric feature similarity measurement longest common subsequence feature descriptor
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Hopf bifurcation of nonlinear system with multisource stochastic factors
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作者 Xinyu Bai Shaojuan Ma +1 位作者 Qianling Zhang Qiyi Liu 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2023年第2期93-97,共5页
The article mainly explores the Hopf bifurcation of a kind of nonlinear system with Gaussian white noise excitation and bounded random parameter.Firstly,the nonlinear system with multisource stochastic fac-tors is red... The article mainly explores the Hopf bifurcation of a kind of nonlinear system with Gaussian white noise excitation and bounded random parameter.Firstly,the nonlinear system with multisource stochastic fac-tors is reduced to an equivalent deterministic nonlinear system by the sequential orthogonal decomposi-tion method and the Karhunen-Loeve(K-L)decomposition theory.Secondly,the critical conditions about the Hopf bifurcation of the equivalent deterministic system are obtained.At the same time the influence of multisource stochastic factors on the Hopf bifurcation for the proposed system is explored.Finally,the theorical results are verified by the numerical simulations. 展开更多
关键词 multisource stochastic factors Gaussian white noise K-L decomposition Hopf bifurcation Random parameter
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China’s poverty assessment and analysis under the framework of the UN SDGs based on multisource remote sensing data
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作者 Mengjie Wang Yanjun Wang +3 位作者 Fei Teng Shaochun Li Yunhao Lin Hengfan Cai 《Geo-Spatial Information Science》 CSCD 2024年第1期111-131,共21页
Poverty has always been a global concern that has restricted human development.The first goal(SDG 1)of the United Nations Sustainable Development Goals(SDGs)is to eliminate all forms of poverty all over the world.The ... Poverty has always been a global concern that has restricted human development.The first goal(SDG 1)of the United Nations Sustainable Development Goals(SDGs)is to eliminate all forms of poverty all over the world.The establishment of a scientific and effective localized SDG 1 evaluation and monitoring method is the key to achieving SDG 1.This paper proposes SDG 1 China district and county-level localization evaluation method based on multi-source remote sensing data for the United Nations Sustainable Development Framework.The temporal and spatial distribution characteristics of China’s poverty areas and their SDG 1 evaluation values in 2012,2014,2016,and 2018 have been analyzed.Based on the SDGs global indicator framework,this paper first constructed SDG 1 China’s district and county localization indicator system and then extracted multidimensional feature factors from nighttime light images,land cover data,and digital elevation model data.Secondly,we establish SDG 1 China’s localized partial least squares estimation model and SDG 1 China’s localized machine learning estimation model.Finally,we analyze and verify the spatiotemporal distribution characteristics of China’s poverty areas and counties and their SDG 1 evaluation values.The results show that SDG 1 China’s district and county localization indicator system proposed in this study and SDG 1 China’s localized partial least squares estimation model can better reflect the poverty level of China’s districts and counties.The estimated model R^(2) is 0.65,which can identify 72.77%of China’s national poverty counties.From 2012 to 2018,the spatial distribution pattern of SDG evaluation values in China’s districts and counties is that the SDG evaluation values gradually increase from western China to eastern China.In addition,the average SDG 1 evaluation value of China’s districts and counties increased by 23%from 2012 to 2018.This paper is oriented to the United Nations SDGs framework,explores the SDG 1 localized evaluation method of China’s districts and counties based on multisource remote sensing data,and provides a scientific and rapid regional poverty monitoring and evaluation program for the implementation of the 2030 agenda poverty alleviation goals. 展开更多
关键词 multisource remote sensing data Sustainable Development Goals(SDGs) poverty indicator system partial least squares machine learning
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Impact of human settlements quality on urban vitality based on multisource data:A case study of Shahekou District,Dalian,China
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作者 LIU He 《Ecological Economy》 2024年第2期139-159,共21页
Urban geography has always been concerned about the influence of human settlements on urban vitality,but few studies reveal the influence of human settlements on urban vitality at a micro-scale.This paper analyzes the... Urban geography has always been concerned about the influence of human settlements on urban vitality,but few studies reveal the influence of human settlements on urban vitality at a micro-scale.This paper analyzes the spatial distribution characteristics of human settlements’quality and urban vitality at the micro-scale using Geodetectors and geographic weighted regression to analyze the relationship between human settlements and urban vitality.The results are shown as follows:there is still a significant development space for human settlements quality in Shahekou District,with obvious spatial dependence characteristics and significant gaps between various systems;the urban vitality of Shahekou District has obvious timeliness,and the urban vitality undergoes significant changes over time,which is related to the human settlements quality.The spatial distribution presents a single core spatial distribution structure with strong relative stability.The spatial distribution of cold and hot spots shows a pattern of“high in the north and low in the south,high in the east and low in the west”,with an increasing trend from southwest to northeast;the reachability of public transport has a significant impact on urban vitality.Its synergy with other variables is the leading force forming the spatial distribution of urban vitality.The environmental system,support system and social system are the significant factors affecting the urban vitality of Shahekou District. 展开更多
关键词 human settlements urban vitality refined management multisource data
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A charging demand prediction method for individual electric vehicle users based on dual-layer multisource data clustering and a LightGBM
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作者 Yunfei Mu Ruichao Zhou +3 位作者 Kangning Zhao Hongjie Jia Guoqiang Zu Ye Yang 《Energy and AI》 2025年第4期546-558,共13页
The charging behaviors of electric vehicle(EV)users exhibit high randomness and individual heterogeneity,with the key parameters such as the charging duration and charged energy levels displaying significant fluctuati... The charging behaviors of electric vehicle(EV)users exhibit high randomness and individual heterogeneity,with the key parameters such as the charging duration and charged energy levels displaying significant fluctuations.Compared with EV cluster-layer prediction,predicting the charging demands of individual users requires not only the analysis of more complex charging behaviors but also the establishment of a coupling model between exogenous variables(e.g.,weather and holidays)and prediction accuracy,thereby imposing higher robustness requirements on prediction algorithms.An individual-user EV charging demand prediction method that in-tegrates multisource data with a dual-layer clustering approach and a light gradient boosting machine(LightGBM)is proposed in this study to address these technical challenges.First,a multisource dataset that incorporates user charging behavior data and exogenous variables(meteorological factors and date types)is constructed.A dual-layer feature extraction mechanism consisting of data-layer clustering for charging type identification and user-layer clustering for user group classification is employed,thereby establishing a classi-fication feature space that characterizes different charging types and user groups.A predictive model is subse-quently developed using the LightGBM algorithm,which directly incorporates classification features as its inputs,effectively mitigating the information loss associated with the traditional categorical variable encoding process.Finally,employing EV users from a typical residential community in northern China as an empirical case,comparative experiments are performed to validate the proposed method,demonstrating its effectiveness at improving prediction accuracy. 展开更多
关键词 multisource data Dual-layer clustering Electric vehicle Individual user Charging demand prediction LightGBM
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Validation of Urban Surface Water Flood Modeling with Multisource Data:Two Case Studies in Baoji and Linyi Cities,China
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作者 Guizhen Guo Jie Yin +4 位作者 Xuesong Yuan Ziqing Zhu Mingfu Guan Dapeng Yu Nigel Wright 《International Journal of Disaster Risk Science》 2025年第5期832-842,共11页
Urban areas are particularly vulnerable to surface water flooding in a changing environment.A large number of urban surface water flood models have been developed to derive flood inundations and support risk managemen... Urban areas are particularly vulnerable to surface water flooding in a changing environment.A large number of urban surface water flood models have been developed to derive flood inundations and support risk management.However,unlike fluvial and coastal flooding,urban pluvial flooding is often associated with shallow water and thus the model is difficult to validate with traditional monitoring data.In this study,we first developed a full two-dimensional(2D)hydrodynamic model for simulating surface water floods.We further evaluated the model performance with multisource data from flood incidents,including official reports and social media data.The model was tested in the cities of Baoji and Linyi,China,where two surface water flood events recently occurred and caused considerable losses and casualties.In total,350 localized flooding incidents were obtained for the two cities(220 in Baoji and 130 in Linyi)and 313 reports were retained after data cleaning(202 in Baoji and 111 in Linyi).Over 90%of the reported flood incidents fall in urban areas where water depths are predicted to be higher than 0.15 m.The results demonstrate that the model is able to derive the broad patterns of flood inundation at the city scale.The approach tested here could be applied to other flood-prone cities and future research could include water depth information for more robust model validation. 展开更多
关键词 Model validation multisource data Surface water fl ooding Urban fl ood modeling
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Indoor multisource channel characteristic for visible light communication 被引量:3
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作者 CHENG Rong YAN Xiao-ming 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2013年第4期106-111,共6页
In this paper, we present a wavelength depended ray-tracing algorithm to model the indoor multisource channel impulse response for visible light communication (VLC). We compare the multipath loss difference between ... In this paper, we present a wavelength depended ray-tracing algorithm to model the indoor multisource channel impulse response for visible light communication (VLC). We compare the multipath loss difference between multisource and unisource channel. We also analyze the root mean square (RMS) delay spread and average time delay of three typical wavelengths as VLC holds a wide spectrum from 380 nm to 780 nm, the spectral reflectance of walls is wavelength-dependent. And the result shows that the blue light emitting diode (LED) owns a larger communication bandwidth than other wavelengths in the room with plastic walls. Also, the path loss of three different wavelengths is compared. 展开更多
关键词 VLC RAY-TRACING multisource wavelength-dependent
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Evaluating the Influence of Multisource Typhoon Precipitation Data on Multiscale Urban Pluvial Flood Modeling 被引量:2
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作者 Yi Lu Jie Yin +4 位作者 Dandan Wang Yuhan Yang Hui Yu Peiyan Chen Shuai Zhang 《International Journal of Disaster Risk Science》 SCIE CSCD 2022年第6期974-986,共13页
Based on station precipitation observations,radar quantitative precipitation estimates(QPE), and radar fusion data during Typhoon Fitow(2013), the influence of multisource precipitation data on multiscale urban typhoo... Based on station precipitation observations,radar quantitative precipitation estimates(QPE), and radar fusion data during Typhoon Fitow(2013), the influence of multisource precipitation data on multiscale urban typhoon pluvial flood modeling is studied. Using Shanghai, China,as the study area, a simplified 2D hydrodynamic model is applied to simulations. Combined with actual flood incidents reported by the public and soil moisture data, we perform multiscale verifications and determine the applicability of three precipitation datasets in the modeling. The results are as follows:(1) At the city scale, although QPE have higher spatial resolution, these estimates are lower than station observations. Radar fusion data have both high accuracy and high spatial resolution. For flood depths above 5 cm, the radar fusion precipitation scenario can improve the matching probability by 6%.(2) At the neighborhood scale, the radar fusion precipitation scenario can effectively mitigate the problems of an uneven spatial distribution of stations and a weak QPE to accurately capture pluvial details.(3)One fixed-point assessment shows that different precipitation data have little influence on the temporal characteristics of the modeling result-all three types of data can accurately reflect flood occurrence times. This work can provide a scientific basis for constructing effective urban pluvial flood monitoring systems. 展开更多
关键词 City and neighborhood scale Flood validation multisource precipitation data Pluvial food modeling SHANGHAI
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Experimental study on the early compressive strength,fluidity,and microstructure of multisource coal-based solid waste cemented backfill 被引量:1
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作者 Wentao Xia Ke Yang +3 位作者 Yongqiang Hou Xin Yu Xiang He Huihui Du 《Green and Smart Mining Engineering》 2024年第4期405-420,共16页
The production of coal-based solid waste(CBSW)from coal mining operations poses a significant threat to the ecological environment in mining regions.This research addresses the proper management of CBSW accumulation b... The production of coal-based solid waste(CBSW)from coal mining operations poses a significant threat to the ecological environment in mining regions.This research addresses the proper management of CBSW accumulation by utilizing coal gangue,fly ash,and gasification slag as primary materials for backfill preparation.This study focused on evaluating the early uniaxial compressive strength and fluidity of the backfill while investigating the changing characteristics of early compressive strength,fluidity,and microstructure during the early age of backfill development.Findings showed that the slurry fluidity significantly decreased as the mass concentration increased,whereas factors such as the aggregate-cement mass ratio,fine aggregate content,and fiber content demonstrated no noticeable impact on slurry fluidity.Notably,the early compressive strength of the backfill decreased significantly with an increase in the aggregate-cement mass ratio;however,increases in the mass concentration and fine aggregate content effectively enhanced the early compressive strength of the backfill,serving as key influencing factors.The inclusion of fiber significantly enhanced the early compressive strength of the backfill,with the optimal fiber concentration determined to be∼0.2wt%.Furthermore,increasing the mass concentration or fine aggregate content alleviated the negative impacts of higher aggregate-cement mass ratios on early compressive strength.However,it must be noted that an elevated fine aggregate content may reduce the reinforcing effects of mass concentration on early compressive strength.This leads to enlarged void structures in the samples,whereas increasing the fine aggregate content reduces the void size and range,thereby improving the early compressive strength of the backfill. 展开更多
关键词 multisource coal-based solid waste Cemented backfill FLUIDITY Early strength MICROSTRUCTURE Failure characteristic
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Performance of XGBoost Ensemble Learning Algorithm for Mangrove Species Classification with Multisource Spaceborne Remote Sensing Data 被引量:1
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作者 Jianing Zhen Dehua Mao +6 位作者 Zhen Shen Demei Zhao Yi Xu Junjie Wang Mingming Jia Zongming Wang Chunying Ren 《Journal of Remote Sensing》 2024年第1期497-512,共16页
Accurately and timely monitoring the spatial distribution and composition of mangrove species is critical for assessing mangroves’health,dynamics,and biodiversity,as well as mangroves’degradation and restoration.Rec... Accurately and timely monitoring the spatial distribution and composition of mangrove species is critical for assessing mangroves’health,dynamics,and biodiversity,as well as mangroves’degradation and restoration.Recent advances in machine learning algorithms,coupled with spaceborne remote sensing technique,offer an unprecedented opportunity to map mangroves at species level with high resolution over large extents.However,a single data source or data type is insufficient to capture the complex features of mangrove species and cannot satisfy the need for fine species classification.Moreover,identifying and selecting effective features derived from integrated multisource data are essential for integrating high-dimensional features for mangrove species discrimination.In this study,we developed a novel framework for mangrove species classification using spectral,texture,and polarization information derived from 3-source spaceborne imagery:WorldView-2(WV-2),OrbitaHyperSpectral(OHS),and Advanced Land Observing Satellite-2(ALOS-2).A total of 151 remote sensing features were first extracted,and 18 schemes were designed.Then,a wrapper method by combining extreme gradient boosting with recursive feature elimination(XGBoost-RFE)was conducted to select the sensitive variables and determine the optical subset size of all features.Finally,an ensemble learning algorithm of XGBoost was applied to classify 6 mangrove species in the Zhanjiang Mangrove National Nature Reserve,China.Our results showed that combining multispectral,hyperspectral,and L-band synthetic aperture radar features yielded the best mangrove species classification results,with an overall accuracy of 94.02%,a quantity disagreement of 4.44%,and an allocation disagreement of 1.54%.In addition,this study demonstrated important application potential of the XGBoost classifier.The proposed framework could provide fine-scale data and conduce to mangroves’conservation and restoration. 展开更多
关键词 map mangroves multisource spaceborne remote sensing mangrove species classification spectral information texture information polarization information XGBoost spaceborne remote sensing techniqueoffer
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Dealing with Multisource Information for Estuarine Flood Risk Appraisal in Two Western European Coastal Areas
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作者 Ana Rodrigues Rilo Alexandre Manuel de Oliveira Soares Tavares +1 位作者 Paula Maria dos Santos Freire JoséLuis Zêzere 《International Journal of Disaster Risk Science》 SCIE CSCD 2022年第2期199-213,共15页
Estuaries are usually affected by compound flooding triggers that cause diverse territorial damages.While fluvial flood risk assessment frameworks are well established in the literature,integrated management instrumen... Estuaries are usually affected by compound flooding triggers that cause diverse territorial damages.While fluvial flood risk assessment frameworks are well established in the literature,integrated management instruments that deal with estuarine flood risk remain incomplete and often lacking.This research presents a methodology to extract relevant information from multiple sources post-event and a database building process that is applied to two contrasting estuaries(the Tagus River estuary in Portugal,and the Shannon River estuary in Ireland)in the Western European coastal area.Overall,a total of 274 documents were analyzed and the information was stored in two databases.Multiple correspondence analysis was applied to extract the most informative and relevant estuarine flood indicators.An integrated estuarine flood risk assessment framework is presented and discussed based on the extracted indicators.The framework is driven by two distinct dimensions(oceanic and hydrographic)and revealed the transversal position of triggers of estuarine floods,reflecting the compounding effects usually present in these areas.The results also highlight two levels of flood risk mostly based on damage typology. 展开更多
关键词 Estuarine floods Estuarine flood indicators Multiple correspondence analysis Post-hazard multisource information Western Europe
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