The Experts below are selected from a list of 144 Experts worldwide ranked by ideXlab platform
Cunjin Xue - One of the best experts on this subject based on the ideXlab platform.
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A Novel Process-Oriented Graph Storage for Dynamic Geographic Phenomena
ISPRS International Journal of Geo-Information, 2019Co-Authors: Cunjin Xue, Jingyi LiuAbstract:There exists a sort of dynamic Geographic Phenomenon in the real world that has a property which is maintained from production through development to death. Using traditional storage units, e.g., point, line, and polygon, researchers face great challenges in exploring the spatial evolution of dynamic phenomena during their lifespan. Thus, this paper proposes a process-oriented two-tier graph model named PoTGM to store the dynamic Geographic phenomena. The core ideas of PoTGM are as follows. 1) A dynamic Geographic Phenomenon is abstracted into a process with a property that is maintained from production through development to death. A process consists of evolution sequences which include instantaneous states. 2) PoTGM integrates a process graph and a sequence graph using a node–edge structure, in which there are four types of nodes, i.e., a process node, a sequence node, a state node, and a linked node, as well as two types of edges, i.e., an including edge and an evolution edge. 3) A node stores an object, i.e., a process object, a sequence object, or a state object, and an edge stores a relationship, i.e., an including or evolution relationship between two objects. Experiments on simulated datasets are used to demonstrate an at least one order of magnitude advantage of PoTGM in relation to relationship querying and to compare it with the Oracle spatial database. The applications on the sea surface temperature remote sensing products in the Pacific Ocean show that PoTGM can effectively explore marine objects as well as spatial evolution, and these behaviors may provide new references for global change research.
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A top-down hierarchical spatio-temporal process description method and its data organization
International Symposium on Spatial Analysis Spatial-Temporal Data Modeling and Data Mining, 2009Co-Authors: Jiong Xie, Cunjin XueAbstract:Modeling and representing spatio-temporal process is the key foundation for analyzing Geographic Phenomenon and acquiring spatio-temporal high-level knowledge. Spatio-temporal representation methods with bottom-up approach based on object modeling view lack of explicit definition of Geographic Phenomenon and finer-grained representation of spatio-temporal causal relationships. Based on significant advances in data modeling of spatio-temporal object and event, aimed to represent discrete regional dynamic Phenomenon composed with group of spatio-temporal objects, a regional spatio-temporal process description method using Top-Down Hierarchical approach (STP-TDH) is proposed and a data organization structure based on relational database is designed and implemented which builds up the data structure foundation for carrying out advanced data utilization and decision-making. The land use application case indicated that process modeling with top-down approach was proved to be good with the spatio-temporal cognition characteristic of our human, and its hierarchical representation framework can depict dynamic evolution characteristic of regional Phenomenon with finer-grained level and can reduce complexity of process description.
Henry Waichung Yeung - One of the best experts on this subject based on the ideXlab platform.
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the limits to globalization theory a Geographic perspective on global economic change
Economic Geography, 2002Co-Authors: Henry Waichung YeungAbstract:AbstractThe nature of globalization and global economic change has been a subject of immense academic research during the past two decades. The Janus face of globalization, however, continues to obfuscate our understanding of its complex processes and alleged Geographic outcomes. In this article, I theorize on the indispensable role of geography in conceptualizing economic globalization. I argue that economic globalization is an inherently Geographic Phenomenon in relation to the transcendence and switchability of Geographic scales and discursive practices as sociospatial constructions. Given its complex spatiality, economic globalization is more a Phenomenon in need of explanations than a universal cause of empirically observable outcomes in the so-called globalization theory. To illustrate my theoretical claims, I analyze the complex interrelationships between globalization processes and the recent Asian economic crisis. Some implications for future globalization research in geography are offered.
Chen Xiao-xiang - One of the best experts on this subject based on the ideXlab platform.
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Simulation of Thünen Model Based on Multi-agent
Computer Simulation, 2007Co-Authors: Chen Xiao-xiangAbstract:The spatial pattern described by Thunen is considered as an option to maximize society's well-being in a hypothetical environment.Thunen location theory is a basis of land-use theory.This paper develops a model based on multi-agent technology.Each farmer agent who maximizes own benefits chooses location and products,and farmer agents' behavior and interactivity contribute to formation of spatial rings structure.The simulation using java-swarm shows that different types of agriculture will be formed in concentric rings around the market,the distance from the center is decided by the slope of bid rent function.The study indicates that the multi-agent modeling approach is a powerful tool for studying complicated Geographic Phenomenon.
Li Zheng - One of the best experts on this subject based on the ideXlab platform.
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Study on Spatio-temporal Data Model About Feature-version
Journal of Chinese Computer Systems, 2008Co-Authors: Li ZhengAbstract:The characteristic of traditional spatio-temporal data model is discussed. Supported by Geodatabase, a spatio-temporal data model based on Feature-version is designed. The logical relations of time and storage structure of model is described in detail. The model decreases the storing spaces, keeps the integrity of Geographic Phenomenon and has efficiency of query. Spatio-temporal database and TGIS of ZhaLong wetland is built subsequently. It manages wetland spatio-temporal data effectively through the realization of historical reconstruction, the development or review of Geographic object and spatio-temporal query.
Enzo Ierardi - One of the best experts on this subject based on the ideXlab platform.
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Vonoprazan and Helicobacter pylori Treatment: A Lesson From Japan or a Limited Geographic Phenomenon?
Frontiers in pharmacology, 2019Co-Authors: Amin Talebi Bezmin Abadi, Enzo IerardiAbstract:Within a short time after the discovery of Helicobacter pylori, its critical role in many gastroduodenal disorders became evident. Many in vitro and in vivo data have proven that infection should be treated in order to avoid lasting colonization which may lead to problematic gastroduodenal diseases. Probiotics, preventive and therapeutic vaccines and antibiotic therapy are the main options proposed to cure these disorders. 25 years ago, triple therapy including a traditional proton pump inhibitor (PPI) and two antibiotics (amoxicillin and clarithromycin or metronidazole) was defined as the best therapy formulation for the H. pylori infection. With the strongly decreased effectiveness of this scheme, many empirical therapeutic regimens have been developed. However, the prevalence of resistance is increasing worldwide and reveals important Geographic differences and even the most recent and effective regimens show some critical points. Therefore, efficacy of vonoprazan-based therapy in regions with low rate of clarithromycin resistance may be limited. In this review, we attempt to open a new window to overcome the problem of antibiotic resistance to H. pylori. In fact, we focused our attention on the possibility that conventional PPI may be replaced by vonoprazan, thus giving rise to the beginning of a new era characterized by an improved therapeutic option for H. pylori infection. Therefore, we hypothesize that switching to vonoprazan as a novel acid blocker for H. pylori treatment might allow an unexpected reassessment of the triple therapy, at least in regions with low rate of clarithromycin resistance. Nevertheless, this optimistic view of the problem could be disproved by the possible failure of vonoprazan based therapeutic regimens outside of Japan in Geographic areas characterized by different rates of antibiotic resistances.