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Distinguishing different subclasses of water bodies for long-term and large-scale statistics of lakes:a case study of the Yangtze River basin from 2008 to 2018

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International Journal of Digital Earth 2021年第2期14卷 202-230页

作者： Jin Luo Zeqiang chen nengcheng chen State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhanPeople’s Republic of China

Long-term and large-scale lake statistics are meaningful for the study of environment change,but many of the existing methods are labourintensive and *** overcome this problem,a novel method for long-term and large-scale lake extraction by shape-factorsand machine-learning-based water body classification is *** experiment was conducted to extract the lakes in the Yangtze River basin(YRB)from 2008 to 2018 with the Joint Research Centre’s Global Surface Water Dataset(JRC GSW)data and OSM *** results show:1)The proposed method is automatically and successfully executed.2)The number of river–lake complexes is between 3008 and 4697,representing 3.56%–5.70%of the total water bodies.3)The areas of the lakes and rivers in the YRB were obtained,and the accuracy of water classification in each year was stable between 90.2%and 93.6%.Comparing the back propagation neural network,random forest,and support vector machine models,we found that the three machine learning models have similar classification accuracy for the scenario.4)Fragmented and incomplete small rivers in the JRC GSW data,unchecked training samples,and overlapped shape factors are the three error *** work will focus on addressing these three error sources.

关键词： Lake extraction water bodies classification the Yangtze River shape metrics machine learning

Use of Service Middleware Based on ECHO with CSW for Discovery and Registry of MODIS Data

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Geo-Spatial Information Science 2010年第3期13卷 191-200页

作者： chen Zeqiang chen nengcheng State Key Laboratory of Information Engineering in Surveying Mapping and Remote Sensing Wuhan University 129Luoyu Road Wuhan 430079 China

Nowadays, NASA is producing several terabytes Moderate Resolution Imaging Spectroradiometer （MODIS） data everyday; how to find the data with criteria, such as specific times, locations, and scales using an international standard becomes more and more important. In this paper, a service-oriented architecture for use of the integration Earth Observation System Clearing- HOuse （ECHO） with the Open Geospatial Consortium （OGC） Catalogue Service--Web profile （CSW） is put forward. The architecture consists of three roles： a service requester （the user）, a service provider （the ECHO metadata server）, and a service broker （the GeoNetwork CSW and MODIS registry service middleware）. The core component-MODIS registry service middleware includes three components： metadata fetcher, metadata transformer, and metadata register. The metadata fetcher is used to fetch metadata from ECHO metadata server; the metadata transformer is responsible for transform metadata from one form to another; the metadata register is in charge of registering ISO19139-based metadata to CSW. A prototype system is designed and implemented by using the service middleware technology and a standard interface and protocol. The feasibility and the response time of registry and retrieval of MODIS data are evaluated by means of a realistic LPDAAC_ECS MODIS data center. The implementation of this prototype system and the experiment show that the architecture and method is feasible and effective.

关键词： ECHO GeoNetwork ISO19139 model mapping metadata transform metadata register

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A capability matching and ontology reasoning method for high precision OGC web service discovery

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International Journal of Digital Earth 2011年第6期4卷 449-470页

作者： nengcheng chen Zeqiang chen Chuli Hu Liping Di State Key Lab for Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhan 430079China Center for Spatial Information Science and Systems George Mason UniversityFairfaxVA 22032USA

Finding the right spatially aware web service in a heterogeneous distributed environment using criteria such as service type,version,time,space,and scale has become a challenge in the integration of geospatial information services.A new method for retrieving Open Geospatial Consortium(OGC)Web Service(OWS)that deals with this challenge using page crawling,link detection,service capability matching,and ontology reasoning,is described in this *** major components are distributed OWS,the OWS search engine,the OWS ontology generator,the ontology-based OWS catalog service,and the ontology-based multi-protocol OWS *** results show that the execution time of this proposed method equals only 0.26 of that of Nutch’s *** addition,the precision is much ***,this proposed method can carry out complex OWS reasoning-based *** is being used successfully for the Antarctica multi-protocol OWS portal of the Geo-Information Web Service Portal of the Polar.

关键词： geospatial information service link detection capability matching OWL-S ontology reasoning

Progress and challenges in the architecture and service pattern of Earth Observation Sensor Web for Digital Earth

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International Journal of Digital Earth 2014年第12期7卷 935-951页

作者： nengcheng chen Xu chen Ke Wang Xiaoguang Niu State Key Laboratory for Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhanChina State Key Laboratory of Software Engineering Wuhan UniversityWuhanChina School of Computer Wuhan UniversityWuhanChina

The Earth Observation(EO)Web is the data acquisition and processing network for digital *** EO Web including Data Web and Sensor Web has become one of the most important aspects of the Digital Earth *** paper summarised the history of the development and status quo of the major types of EO data web service systems,including architecture,service pattern and *** concepts,development and implementation of the EO Sensor Web were ***,we analysed the requirements on the architecture of the next-generation EO Sensor Web system,namely Space-borne-Airborne-Ground integrated Intelligent EO Sensor Web system,and highlighted the virtualization,intelligent,pervasive and active development tendency of such system.

关键词： earth observation observation web sensor web service pattern system architecture

Soil moisture estimation based on BeiDou Bl interference signal analysis

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Science China Earth Sciences 2016年第12期59卷 2427-2440页

作者： YAN SongHua ZHAO Fen chen nengcheng GONG JianYa School of Electronic Information Wuhan University State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan University

BeiDou Navigation Satellite System reflectometry(BDS-R) is an emerging area of BD(BeiDou) applications that uses multipath reflected signals in microwave remote *** moisture estimation is one of the potential important applications of *** study aims to investigate the feasibility of soil moisture estimation based on BD B1 band interference signals,which are composed of direct and reflected BD signals and can be readily captured using low-cost commercial BDS *** this paper,a theoretical background for soil estimation from interference signals was introduced,and an analysis of field experimental data was ***,a cosine model for the interference signal power was built,and a non-uniform power spectrum analysis was performed on the received interference signals to determine its main ***,a least squares curve fitting was applied on the interference signal power to extract its *** relationship between the soil moisture and the phase was then *** months of experimental data were collected at BaoXie,Wuhan and analyzed for further *** results show that the phase of the interference signals increases with the increase of soil *** correlation coefficient between the phase and the in-situ soil moisture value is approximately ***,the relationship between the phase and soil moisture is employed to estimate soil *** show that using BDS-R to measure soil moisture is feasible,which demonstrates a great potential of new application of the BD system.

关键词： BDS-R Soil moisture estimation Interference signal Non-uniform power spectrum Least squares curve fitting SNR

Spatio-temporal enabled urban decision-making process modeling and visualization under the cyber-physical environment

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Science China(Information Sciences) 2015年第10期58卷 53-69页

作者： WANG Wei HU ChuanBo chen nengcheng XIAO ChangJiang WANG Chao chen ZeQiang State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan University Collaborative Innovation Center of Geospatial Technology

Urban management is increasingly dependent on the construction of cyber-physical systems, which have been widely deployed in multiple fields, including agriculture, transportation, and health care. Cyberphysical systems provide a large volume of big sensory data. Thus, the application of big data for urban emergency decision-making has become a challenge. Traditional decision-making models are unable to overcome several technical problems, including spatio-temporal information support and access to real-time service for disaster management and emergency response. In this paper, we propose a spatio-temporal enabled urban decision-making process modeling method in the cyber-physical environment and discuss the development off our basic metadata components, the definition of eleven-tuple information description structure. A prototype system is designed for modeling registering, management, visualization, and other functions. Decision-making processes are implemented as composite process chains through three phases, i.e., decision-making process modeling,instantiation of the decision-making process chain and execution of the decision-making process chain. For application to gas leak events, the decision-making process is executed to confirm the feasibility of the proposed decision-making process modeling method and the flexibility of the eleven-tuple information structure.

关键词： decision-making process meta-model process chain Sensor ML emergency management

Integration of hydrological observations into a Spatial Data Infrastructure under a Sensor Web environment

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International Journal of Digital Earth 2013年第S02期6卷 22-40页

作者： Zhong Zheng nengcheng chen Pengfei Li Wei Wang State Key Lab for Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhan 430079China

Various sensors connected to the World Wide Web are used to obtain real-time hydrological ***,real-time management and utilization of such distributed in situ observations in the cyber-physical environment becomes possible.A Sensor Observation Service(SOS)chaining Web Feature Service(WFS)method is proposed to integrate geographical reference observation data collected by a hydrological Sensor Web into a virtual *** method hides the complexity of a series of information and service models in the Sensor Web realm to enable the integration of heterogeneous distributed hydrological data sources into a Spatial Data Infrastructure(SDI).The core components-a dynamic schema transformer and automatic information extractor-were designed and *** SOS schema is matched to WFS schema that uses the schema transformer *** information extractor extracts and serves features automatically,conforming to standard SOS operations for observation retrieval and *** experiments conducted on the Jinsha River tested this proposed *** show that the proposed approach allows the integration of SOS servers into legacy applications that have a higher degree of availability within many ***,this is accompanied with the drawback that only a limited part of the SOS functionality is available to clients.

关键词： Sensor Web data management service middleware Sensor Observation Service Web Feature Service

KING GEORGE ISLAND SPATIAL DATA MODEL

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Geo-Spatial Information Science 2001年第2期4卷 63-69页

作者： chen nengcheng GONG Jianya LIESMARS Wuhan University

Distribution,interoperability,interactivity,component are four main features of distributed *** on the principle of hypermap,hypermedia and distributed database,the paper comes up with a kind of distributed spatial data model which is in accordance with those features of distributed *** model takes catalog service as the outline of spatial information globalization,and defines data structure of hypermap node in different *** on the model,it is feasible to manage and process distributed spatial information,and integrate multi_source,heterogeneous spatial data into a ***,to retrieve and access spatial data via Internet is only by theme or map *** the concept of the model,it is possible to retrieve,load,and link spatial data by vector_based graphics on the Internet.

关键词： King George Island distribution GIS hypermap data model interoperability

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A New Approach to a Local E-Government Portal for Information Management and Deep Searching

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Wuhan University Journal of Natural Sciences 2006年第5期11卷 1161-1166页

作者： YANG Rui chen nengcheng LIU Zhixue School of Management Huazhong University ofScience and Technology Wuhan 430074 Hubei China State Key Laboratory of Information Engineering onSurveying Mapping and Remote Sensing WuhanUniversity Wuhan 430072 Hubei China

The paper introduces a new approach, that is, semantic Web techniques, to shed a new light on the solutions for local e-government information portal. After taking the comparison between traditional approaches and semantic approaches, the design of arehitecture and components of a local e-government information portal are illustrated in details based on semantic technologies. The paper also researches on the core technologies of implementation of the new approach, including the definition of e-government information portal Ontologies and searching algorithms.

关键词： semantic e-government portal

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