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Architecture and key technologies of grid geographic information system

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Science China(Technological Sciences) 2008年第S1期51卷 102-113页

作者： FANG Yu,HUANG Zhou,CHEN Bin,WU Lun & YIN DaFei Institute of Remote Sensing and Geographic information system,Peking University,Beijing 100871,China Institute of Remote Sensing and Geographic information system Peking University Beijing 100871 China

The highly efficient and stable collaborative computation platform for geospatial information can be constructed on the basis of Grid computing technology,com-bined with Peer-to-Peer (P2P) computing technology and geospatial database technology. This paper proposed the architecture and key technologies of the Grid GIS (Geographic information system) incorporated with P2P structure,and corre-spondingly a Grid GIS prototype named Nebula was designed and then imple-mented. Nebula is a suite of middleware for geospatial Grid computing,which could be deployed onto various service nodes in network. Based on Grid protocols and infrastructure,Nebula provides invocation interfaces to users in form of Grid services. By using P2P message based communication mechanism,complex geospatial computation tasks could be accomplished by Nebula in a collaborative way. This paper introduced Nebula's architecture and key modules,and according to experimental data,we discussed the Grid GIS's advantages,application scenar-ios and future directions.

关键词： Grid GIS distributed geospatial computing Peer-to-Peer computing

Enhanced geographic information system-based mapping of local climate zones in Beijing, China

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Science China(Technological Sciences) 2019年第12期62卷 2243-2260页

作者： QUAN JinLing State Key Laboratory of Resources and Environmental information system Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences

The vague urban-rural dichotomy severely restricts effective comparisons and communications among urban heat island studies.A local climate zone(LCZ) scheme has therefore been developed to classify urban and natural landscapes in a standardized and universal manner. Despite LCZ mapping efforts in worldwide cities, this study attempts to propose an enhanced geographic information system-based workflow to enable the hierarchical classification of LCZs with fewer indicators but higher accuracies while considering supplementary classes and subclasses. Specifically, five morphological and coverage indicators that were easily obtained and well differentiated among LCZs were derived from a city street map and satellite images, and 25 LCZs(including 16 standard, 3 supplementary, and 6 sub-classified zones) were determined at a block-level according to the indicator hierarchy and criteria. The method was performed over Beijing, China, and evaluations by field surveys and google earth images showed a high accuracy with little noise and sharp boundaries, outperforming the widely-used remote sensing-based method of the World Urban Database and Access Portal Tools, particularly in terms of building height and heavy industry. Results also demonstrate that the Beijing core was dominated by open(including extremely open) mid-rise buildings(28.7%) and open lowrise buildings(12.8%), forming an inner-low-middle-high-outer-low annular building-height pattern. Significant land surface temperature differences were detected among the LCZs, where the low-rise and compact LCZs had higher temperatures than the mid-/high-rise and open LCZs during daytime, and subclasses LCZ XB/C/D(LCZ XE/F) generated lower(higher) temperatures than their parent classes in May. This method was proposed to augment the LCZ mapping system and further support applications(e.g., urban planning/management and climate/weather modeling) in high-density cities similar to Beijing.

关键词： geographic information system(GIS) remote sensing local climate zone(LCZ) land surface temperature urban morphology

Basic theory and key technologies for marine geographic information system

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Acta Oceanologica Sinica 2006年第2期25卷 80-86页

作者： SU Fenzhen YANG Xiaomei XU Jun ZHANG Tianyu LUO Jiancheng Institute of Geography Science and Resource Research Chinese Academy of Sciences Beijing100101 China Marine Geographic information system Center State Key Laboratory of Geographical Information System Chinese Academy of Sciences Beijing 100101 China Department of Geography University of Wisconsin-Madison Madison Wisconsin 53706 USA

Marine geographic information system （MGIS） has great ability to deal with the spatio-temporal problems and has potential superiority when it is applied to oceanography. Using the feature extraction of oceanic phenomena as a case study, the functions of the MGIS are analyzed, and thus the position of MGIS in the oceanography is defined. Comparing the requirement of MGIS with that of the traditional GIS which has been developed in the terrestrial applications in the past four decades, the frame for the functions of MGIS is constructed. According to the established MGIS, some key technologies are discussed in detail with emphasis on the specialities which can distinguish the MGIS from the traditional GIS.

关键词： marine geographic information system remote sensing function structure data mining

Assessing the Response of Seasonal Variation of Net Primary Productivity to Climate Using Remote Sensing Data and Geographic information system Techniques in Xinjiang

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Journal of Integrative Plant Biology 2008年第12期50卷 1580-1588页

作者： Dai-Liang Peng Jing-Feng Huang Cheng-Xia Cai Rui Deng Jun-Feng Xu Institute of Agriculture Remote Sensing and information system Application Zhejiang University Hangzhou 310029 China Xinjiang Institute of Meteorology Urumchi 830002 China

Net primary productivity （NPP） is a key component of energy and matter transformation in the terrestrial ecosystem, and the responses of NPP to global change locally and regionally have been one of the most important aspects in climatevegetation relationship studies. In order to isolate causal climatic factors, it is very important to assess the response of seasonal variation of NPP to climate. In this paper, NPP in Xinjiang was estimated by NOAA/AVHRR Normalized Difference Vegetation Index （NDVI） data and geographic information system （GIS） techniques. The impact of climatic factors （air temperature, precipitation and sunshine percentage） on seasonal variations of NPP was studied by time lag and serial correlation ageing analysis. The results showed that the NPP for different land cover types have a similar correlation with any one of the three climatic factors, and precipitation is the major climatic factor influencing the seasonal variation of NPP in Xinjiang. It was found that the positive correlation at 0lag appeared between NPP and precipitation and the serial correlation ageing was 0 d in most areas of Xinjiang, which indicated that the response of NPP to precipitation was immediate. However, NPP of different land cover types showed significant positive correlation at 2 month lag with air temperature, and the impact of which could persist 1 month as a whole. No correlation was found between NPP and sunshine percentage.

关键词： climate geographic information system techniques net primary productivity remote sensing seasonal variation serial correlation ageing time lag.

VGIS-COLLIDE:an effective collision detection algorithm for multiple objects in virtual geographic information system

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International Journal of Digital Earth 2011年第1期4卷 65-77页

作者： Feixiong Luo Ershun Zhong Junlai Cheng Yuefeng Huang State Key Lab of Resources and Environmental information system Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingChina

Collision detection is an important component in simulation applications which are based on virtual geographic information system(VGIS).In this paper,an effective collision detection algorithm for multiple objects in VGIS,VGISCOLLIDE,is *** algorithm firstly integrates existing quadtree,which is the global hierarchical structure of VGIS,with axis-aligned bounding box of object to perform the broad-phase of collision *** that,exact collision detection between two objects which have passed the broad-phase of collision detection is *** algorithm makes no assumption about input primitives or object’s motion and is directly applicable to all triangulated *** can be applicable to both rigid and deformable objects without *** performance of the algorithm has been demonstrated in several environments consisting of a high number of objects with hundreds of thousands of triangles.

关键词： collision detection multiple objects quadtree VGIS

Multi-Scale Dilated Convolution Network for SPECT-MPI Cardiovascular Disease Classification with Adaptive Denoising and Attenuation Correction

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 299-327页

作者： A.Robert Singh Suganya Athisayamani Gyanendra Prasad Joshi Bhanu Shrestha Department of Computational Intelligence SRM Institute of Science and TechnologyKattankulathur603203Tamil NaduIndia School of Computing Sastra Deemed to be UniversityThanjavur613401Tamil NaduIndia Department of Artificial Intelligence&Software Kangwon National UniversitySamcheok25913Republic of Korea Department of information Convergence system Graduate School of Smart ConvergenceKwangwoon UniversitySeoul01897Republic of Korea

Myocardial perfusion imaging(MPI),which uses single-photon emission computed tomography(SPECT),is a well-known estimating tool for medical diagnosis,employing the classification of images to show situations in coronary artery disease(CAD).The automatic classification of SPECT images for different techniques has achieved near-optimal accuracy when using convolutional neural networks(CNNs).This paper uses a SPECT classification framework with three steps:1)Image denoising,2)Attenuation correction,and 3)Image *** denoising is done by a U-Net architecture that ensures effective image *** correction is implemented by a convolution neural network model that can remove the attenuation that affects the feature extraction process of ***,a novel multi-scale diluted convolution(MSDC)network is *** merges the features extracted in different scales and makes the model learn the features more *** scales of filters with size 3×3 are used to extract *** three steps are compared with state-of-the-art *** proposed denoising architecture ensures a high-quality image with the highest peak signal-to-noise ratio(PSNR)value of *** proposed classification method is compared with the five different CNN models,and the proposed method ensures better classification with an accuracy of 96%,precision of 87%,sensitivity of 87%,specificity of 89%,and F1-score of 87%.To demonstrate the importance of preprocessing,the classification model was analyzed without denoising and attenuation correction.

关键词： SPECT-MPI CAD MSDC denoising attenuation correction classification

Decentralized fault diagnosis of discrete-event systems with unreliable sensors using linear temporal logic

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Science China(information Sciences) 2025年第1期 322-341页

作者： Weijie DONG Shaoyuan LI Xiang YIN Key Laboratory of system Control and information Processing Ministry of EducationDepartment of Automation Shanghai Jiao Tong University

In this paper,we investigate a decentralized diagnosis problem of a discrete-evnt system(DES) subject to unreliable sensors,where the sensor observations of local diagnosers may be non-deterministic as a result of possible *** studies on decentralized robust diagnosis can only deal with different types of sensor failures separately,e.g.,all sensors suffer from the same type of sensor failures such as intermittent sensor failures or permanent sensor ***,since sensors of different local diagnosers may face different external environments and have different internal characteristics,sensors corresponding to different local diagnosers may also have their own fault *** this paper,we propose a flexible framework of decentralized diagnosis for DES subject to unreliable sensors such that sensors of different local diagnosers are permitted to have different types of sensor *** this end,we extend the existing decentralized diagnosis framework to the case where there exist common sensors broadcasting their observations to all local *** apply linear temporal logic(LTL) to constrain infinite behaviors of private sensors of local diagnosers and common ***,a new notion of φ-codiagnosability is proposed as the necessary and sufficient condition for the existence of a decentralized diagnoser that works correctly under sensors,satisfying LTL-based sensor ***,we provide an effective approach to verify the φ-codiagnosability.

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DPD Algorithm for Moving Source Based on Doppler Frequency Shifts: Case of Known Waveforms

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Chinese Journal of Electronics 2019年第5期28卷 978-986页

作者： WANG Ding YIN Jiexin YU Hongyi Institute of information system Engineering Information Engineering University

We focus on the Direct position determination(DPD) of a moving narrowband source based on Doppler frequency shifts of signals with known *** common motion models are considered: the Constant velocity(CV) model and the Constant acceleration(CA) model. The DPD cost function is obtained after some algebraic manipulations using the Maximum likelihood(ML) criterion. To develop a computationally efficient optimization algorithm, we present a preliminary mathematical result that plays a fundamental role in development of the proposed algorithm. Subsequently, a Newton iterative algorithm is tailored to the two motion models to determine the moving transmitter’s *** compared with multidimensional grid searching, the proposed algorithm is more computationally attractive without compromising its estimation *** results confirm the superiority of the proposed algorithm.

关键词： Direct position determination(DPD) Doppler frequency shifts Moving emitter Known waveforms

Performance of cumulant-based rank reduction estimator in presence of unexpected modeling errors

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Journal of Central South University 2015年第3期22卷 992-1001页

作者：王鼎 Institute of information system Engineering PLA Information Engineering University

Compared with the rank reduction estimator(RARE) based on second-order statistics(called SOS-RARE), the RARE based on fourth-order cumulants(referred to as FOC-RARE) can handle more sources and restrain the negative impacts of the Gaussian colored noise. However, the unexpected modeling errors appearing in practice are known to significantly degrade the performance of the RARE. Therefore, the direction-of-arrival(DOA) estimation performance of the FOC-RARE is quantitatively derived. The explicit expression for direction-finding(DF) error is derived via the first-order perturbation analysis, and then the theoretical formula for the mean square error(MSE) is given. Simulation results demonstrate the validation of the theoretical analysis and reveal that the FOC-RARE is more robust to the unexpected modeling errors than the SOS-RARE.

关键词： fourth-order cumulants(FOC) rank reduction estimator(RARE) modeling error mean square error(MSE)