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Slope displacement prediction based on multisource domain transfer learning for insufficient sample data
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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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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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Integrating multisource RS data and GIS techniques to assist the evaluation of resource-environment carrying capacity in karst mountainous area 被引量:8
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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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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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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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Comprehensive drought monitoring in Yunnan Province, China using multisource remote sensing data 被引量:1
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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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A Multisource Contour Matching Method Considering the Similarity of Geometric Features 被引量:6
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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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Effects of periodically varying codes on separation of multisource blended data
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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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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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A novel minority sample fault diagnosis method based on multisource data enhancement
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作者 Yiming Guo Shida Song Jing Huang 《International Journal of Mechanical System Dynamics》 EI 2024年第1期88-98,共11页
Effective fault diagnosis has a crucial impact on the safety and cost of complex manufacturing systems.However,the complex structure of the collected multisource data and scarcity of fault samples make it difficult to... Effective fault diagnosis has a crucial impact on the safety and cost of complex manufacturing systems.However,the complex structure of the collected multisource data and scarcity of fault samples make it difficult to accurately identify multiple fault conditions.To address this challenge,this paper proposes a novel deep-learning model for multisource data augmentation and small sample fault diagnosis.The raw multisource data are first converted into two-dimensional images using the Gramian Angular Field,and a generator is built to transform random noise into images through transposed convolution operations.Then,two discriminators are constructed to evaluate the authenticity of input images and the fault diagnosis ability.The Vision Transformer network is built to diagnose faults and obtain the classification error for the discriminator.Furthermore,a global optimization strategy is designed to upgrade parameters in the model.The discriminators and generator compete with each other until Nash equilibrium is achieved.A real-world multistep forging machine is adopted to compare and validate the performance of different methods.The experimental results indicate that the proposed method has multisource data augmentation and minority sample fault diagnosis capabilities.Compared with other state-of-the-art models,the proposed approach has better fault diagnosis accuracy in various scenarios. 展开更多
关键词 multisource data augmentation minority sample fault diagnosis complex manufacturing system global optimization Vision Transformer
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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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Insights into multisource sludge distributed in the Yangtze River basin, China: Characteristics,correlation, treatment and disposal 被引量:1
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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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Evaluating the Influence of Multisource Typhoon Precipitation Data on Multiscale Urban Pluvial Flood Modeling 被引量:1
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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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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 José Luis 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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An evaluation of integrating multisourced sensors for disaster management
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作者 Farzad Alamdar Mohsen Kalantari Abbas Rajabifard 《International Journal of Digital Earth》 SCIE EI CSCD 2015年第9期727-749,共23页
Disaster management and in particular disaster response phase are highly timesensitive and dynamic processes,demanding that real-time information reaches disaster responders prior making critical decisions.During the ... Disaster management and in particular disaster response phase are highly timesensitive and dynamic processes,demanding that real-time information reaches disaster responders prior making critical decisions.During the last decade,disaster management has been widely enabled through utilizing spatial data sourcing and related technologies in the whole process of collection,access,and usage of disaster information.Currently,there are unique challenges that cannot be met without incorporating in situ sensing as an emerging technology for sourcing and managing disaster information.These include(1)high temporal and spatial resolution of information,(2)broad range of disaster data,and(3)automated operations.Incorporating in situ sensing into the disaster management process can potentially address such challenges by providing data that support all of these requirements.Following an examination of current concepts and methods for integrating multisourced sensors,a framework of the requirements for integrating in situ sensors for disaster management,is suggested.Based on this framework and its components,an evaluation of the methods is developed and applied.The results highlight that information integration of multisourced sensors is a major challenge and has not yet adequately addressed for sensor data enablement of disaster management. 展开更多
关键词 Disaster management in situ sensing multisourced sensors sensor web sensor network INTEGRATION
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Estimating distribution of water uptake with depth of winter wheat by hydrogen and oxygen stable isotopes under different irrigation depths 被引量:10
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作者 GUO Fei MA Juan-juan +3 位作者 ZHENG Li-jian SUN Xi-huan GUO Xiang-hong ZHANG Xue-lan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第4期891-906,共16页
Crop root system plays an important role in the water cycle of the soil-plant-atmosphere continuum. In this study, com- bined isotope techniques, root length density and root cell activity analysis were used to invest... Crop root system plays an important role in the water cycle of the soil-plant-atmosphere continuum. In this study, com- bined isotope techniques, root length density and root cell activity analysis were used to investigate the root water uptake mechanisms of winter wheat (Triticum aesfivum L.) under different irrigation depths in the North China Plain. Both direct inference approach and multisource linear mixing model were applied to estimate the distribution of water uptake with depth in six growing stages. Results showed that winter wheat under land surface irrigation treatment (Ts) mainly absorbed water from 10-20 cm soil layers in the wintering and green stages (66.9 and 72.0%, respectively); 0-20 cm (57.0%) in the jointing stage; 0-40 (15.3%) and 80-180 cm (58.1%) in the heading stage; 60-80 (13.2%) and 180-220 cm (35.5%) in the filling stage; and 0-40 (46.8%) and 80-100 cm (31.0%) in the ripening stage. Winter wheat under whole soil layers irrigation treatment (Tw) absorbed more water from deep soil layer than Ts in heading, filling and ripening stages. Moreover, root cell activity and root length density of winter wheat under TW were significantly greater than that of Ts in the three stages. We concluded that distribution of water uptake with depth was affected by the availability of water sources, the root length density and root cell activity. Implementation of the whole soil layers irrigation method can affect root system distribution and thereby increase water use from deeper soil and enhance water use efficiency. 展开更多
关键词 hydrogen and oxygen stable isotopes multisource linear mixing model winter wheat distribution of wateruptake with depth
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Forest type identification by random forest classification combined with SPOT and multitemporal SAR data 被引量:4
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作者 Ying Yu Mingze Li Yu Fu 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第5期1407-1414,共8页
We developed a forest type classification technology for the Daxing'an Mountains of northeast China using multisource remote sensing data.A SPOT-5 image and two temporal images of RADARSAT-2 full-polarization SAR wer... We developed a forest type classification technology for the Daxing'an Mountains of northeast China using multisource remote sensing data.A SPOT-5 image and two temporal images of RADARSAT-2 full-polarization SAR were used to identify forest types in the Pangu Forest Farm of the Daxing'an Mountains.Forest types were identified using random forest(RF) classification with the following data combination types: SPOT-5 alone,SPOT-5 and SAR images in August or November,and SPOT-5 and two temporal SAR images.We identified many forest types using a combination of multitemporal SAR and SPOT-5 images,including Betula platyphylla,Larix gmelinii,Pinus sylvestris and Picea koraiensis forests.The accuracy of classification exceeded 88% and improved by 12% when compared to the classification results obtained using SPOT data alone.RF classification using a combination of multisource remote sensing data improved classification accuracy compared to that achieved using single-source remote sensing data. 展开更多
关键词 Random forest classification MULTITEMPORAL multisource remote sensing data Polarization decomposition
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Data⁃Based Feedback Relearning Algorithm for Robust Control of SGCMG Gimbal Servo System with Multi⁃source Disturbance 被引量:3
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作者 ZHANG Yong MU Chaoxu LU Ming 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2021年第2期225-236,共12页
Single gimbal control moment gyroscope(SGCMG)with high precision and fast response is an important attitude control system for high precision docking,rapid maneuvering navigation and guidance system in the aerospace f... Single gimbal control moment gyroscope(SGCMG)with high precision and fast response is an important attitude control system for high precision docking,rapid maneuvering navigation and guidance system in the aerospace field.In this paper,considering the influence of multi-source disturbance,a data-based feedback relearning(FR)algorithm is designed for the robust control of SGCMG gimbal servo system.Based on adaptive dynamic programming and least-square principle,the FR algorithm is used to obtain the servo control strategy by collecting the online operation data of SGCMG system.This is a model-free learning strategy in which no prior knowledge of the SGCMG model is required.Then,combining the reinforcement learning mechanism,the servo control strategy is interacted with system dynamic of SGCMG.The adaptive evaluation and improvement of servo control strategy against the multi-source disturbance are realized.Meanwhile,a data redistribution method based on experience replay is designed to reduce data correlation to improve algorithm stability and data utilization efficiency.Finally,by comparing with other methods on the simulation model of SGCMG,the effectiveness of the proposed servo control strategy is verified. 展开更多
关键词 control moment gyroscope feedback relearning algorithm servo control reinforcement learning multisource disturbance adaptive dynamic programming
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Evaluation of CMPAS precipitation products over Sichuan,China 被引量:2
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作者 Shiying Li Xiaolong Huang +2 位作者 Wei Wu Bing Du Yuhe Jiang 《Atmospheric and Oceanic Science Letters》 CSCD 2022年第2期47-53,共7页
High-quality and high-resolution precipitation data are the basis for mesoscale numerical weather forecasting,model verification,and hydrological monitoring,which play an important role in meteorological and hydrologi... High-quality and high-resolution precipitation data are the basis for mesoscale numerical weather forecasting,model verification,and hydrological monitoring,which play an important role in meteorological and hydrological disaster prevention and mitigation.In this study,high-density rain gauge data are used to evaluate the fusion accuracy of the China Meteorological Administration Multisource Precipitation Analysis System(CMPAS),and four CMPAS products with different spatial and temporal resolution and different data sources are compared,to derive the applicability of CMPAS.Results show that all the CMPAS products show high accuracy in the Sichuan Basin,followed by Panxi Area and the western Sichuan Plateau.The errors of the four products all rise with the increase in precipitation.CMPAS overestimates precipitation in summer and autumn and underestimates it in spring and winter.Overall,the applicability of these fused data in the Sichuan Basin is quite good.Due to the lack of observations and the influence of the terrain and meteorological conditions,the evaluation of CMPAS in the plateau area needs further analysis. 展开更多
关键词 multisource precipitation products High-resolution precipitation CMPAS Applicability assessment
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Depressed Acne Scars—Effective, Minimal Downtime Treatment with a Novel Smooth Motion Non-Insulated Microneedle Radiofrequency Technology 被引量:6
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作者 Yoram Harth Monica Elman +1 位作者 Einat Ackerman Ido Frank 《Journal of Cosmetics, Dermatological Sciences and Applications》 2014年第3期212-218,共7页
Background: The microneedle fractional RF handpiece used in our study (Intensif Handpiece, EndyMed Medical, Caesarea, Israel) is a novel handpiece that uses a tip with 25 non-insulated, gold plated microneedle electro... Background: The microneedle fractional RF handpiece used in our study (Intensif Handpiece, EndyMed Medical, Caesarea, Israel) is a novel handpiece that uses a tip with 25 non-insulated, gold plated microneedle electrodes. The needles are inserted into the skin by a specially designed electronically controlled, smooth motion motor minimizing patient discomfort. RF emission delivered over the whole dermal portion of the needle allows effective coagulation resulting in minimal or no bleeding, together with bulk volumetric heating. Study Design/Materials and Methods: The study included 20 patients, treated for depressed acne scars using the IntensifTM?Microneedles handpiece (EndyMed PRO Platform System, EndyMed Medical, Caesarea, Israel). The degree of clinical improvement was assessed by the global aesthetic improvement scale (GAIS) and subjects satisfaction by post treatment questionnaires. Results: The number of treatments per patient varied between 1 and 6 (average 3.3 treatments per patient). Eleven patients (55%) reported none to minimal pain, six (30%) moderate discomfort and only three (15%) reported significant pain. Objective evaluation of the improvement by a board certified dermatologist showed improvement in 95% of patients. 25% showed excellent improvement, 50% experienced good improvement, and the 20% showed minimal improvement. One patient showed no improvement. Conclusions: The presented results show that the tested electronically controlled motorized insertion, non-insulated microneedle treatment technology provides a minimal discomfort, minimal downtime, effective and safe treatment for depressed acne scars. 展开更多
关键词 MICRONEEDLES Radio-Frequency Acne SCARS RF multisource Fractional Lasers Non-Insulated
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