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Landfill Site Suitability Assessment Using Geographic Information System (GIS) and Analytic Hierarchy Process (AHP) in Butuan City, Philippines
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作者 Francis Jhun T.Macalam Kaleb P.Arreza +1 位作者 Angelica T.Magpantay Kristine Y.Rabaño 《Journal of Environmental & Earth Sciences》 2023年第1期95-107,共13页
Landfilling is one of the most effective and responsible ways to dispose of municipal solid waste(MSW).Identifying landfill sites,however,is a challenging and complex undertaking because it depends on social,environme... Landfilling is one of the most effective and responsible ways to dispose of municipal solid waste(MSW).Identifying landfill sites,however,is a challenging and complex undertaking because it depends on social,environmental,technical,economic,and legal issues.This study aims to map the optimal sites that were environmentally suitable for locating a landfill site in Butuan City,Philippines.With reference to the policy requirements from DENR Section I,Landfill Site Identification Criteria and Screening Guidelines of National Solid Waste Management Commission,the integration of a Geographic Information System(GIS)model builder and Analytical Hierarchy Process(AHP)has been used in this study to address the aforementioned challenges related to the landfill site suitability analysis.Based on the generated sanitary landfill suitability map,results showed that Barangay Tungao(1131.42967 ha)and Florida(518.48 ha)were able to meet and consider the three(3)main components,namely economic,environmental,and physical criteria,and are highly suit­able as landfill site locations in Butuan City.It is recommended that there will conduct a geotechnical evaluation,involv­ing rigorous geological and hydrogeological assessment employing a combination of site investigation and laboratory techniques.In addition,additional specific social,ecological,climatic,and economic factors need to be considered(i.e.including impact on humans,flora,fauna,soil,water,air,climate,and landscape). 展开更多
关键词 geographic information system Sanitary landfill Analytic hierarchy process Butuan City Site suitability
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Locating Global System for Mobile Communication(GSM)Base Stations Using Geographic Information System(GIS)
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作者 Bamidele Moses Kuboye Victor Gbenga Abiodun 《Journal of Geographical Research》 2023年第4期1-10,共10页
The global system for mobile communication(GSM)is planned to meet the needs of the whole subscribers.The number of subscribers increased as the population increased due to the acceptance of GSM services by the subscri... The global system for mobile communication(GSM)is planned to meet the needs of the whole subscribers.The number of subscribers increased as the population increased due to the acceptance of GSM services by the subscribers.Thus,there should be a way to monitor base stations that will meet the increasing demand of subscribers in any area as a population surge will lead to more subscriptions.This will allow GSM network operators to serve their subscribers better and ease network congestion.This work presents a review of mobile evolution from the first generation to the fifth generation.A review of global positioning system(GPS)technology and its applications to geographic information systems(GIS)was done.The coordinates of these base stations were taken using a GPS device.These base station coordinates were then exported to QGIS for the design of the map.Thereafter,the output map was then integrated into the website.The discussions on the results followed and some useful suggestions given will go a long way to help the operators of GSM in Nigeria and in general.If the propositions given are adhered to,it will go a long way to help the operators reduce congestion on their network and thereby increase the satisfaction of the subscribers. 展开更多
关键词 Global system for mobile communication(GSM) Global positioning system(GPS) geographic information system(GIS) Subscriber MAP IMAGES
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Basic theory and key technologies for marine geographic information system 被引量:8
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作者 SU Fenzhen YANG Xiaomei +2 位作者 XU Jun ZHANG Tianyu LUO Jiancheng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2006年第2期80-86,共7页
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 pheno... 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. 展开更多
关键词 marine geographic information system remote sensing function structure data mining
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Spatial variations of aluminum species in drinking water supplies in Xi'an studied applying geographic information system 被引量:3
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作者 Wendong Wang,Hua Li,Xiaochang Wang,Yongjun Liu School of Environmental and Municipal Engineering,Xi’an University of Architecture and Technology,Xi’an 710055,China. 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第4期519-525,共7页
This article aimed to investigate the variation of aluminum species and the effects of coagulant type and water quality on aluminum speciation in drinking water. Statistical analysis showed that the concentration of t... This article aimed to investigate the variation of aluminum species and the effects of coagulant type and water quality on aluminum speciation in drinking water. Statistical analysis showed that the concentration of total aluminum (AlT) of drinking water in Xi' an ranged from 0.051 to 0.417 mg/L and the concentration of A1T in about 24.7% studied samples was higher than the currently recommended value (0.2 mg/L). The areas fed by surface water plants had a larger portion (39.4%) of samples over the recommended value. In drinking water treated by alum coagulant, the average concentration of monomeric aluminum (Ala) was higher than that in water treated by poly aluminum chlorine (PACl) and poly aluminum ferric chloride (PAFC). The average concentrations of polynuclear aluminum (Alb) and colloidal/suspended aluminum (Ale) in the drinking water treated by alum were lower than those in water treated by PACl and PAFC. There was a notable decrease in AlT along with the delivery pipeline away from the plants, with an average decline of about 36 μg/(L-km). Besides coagulant type, water quality also could affect aluminum speciation. In drinking water without orthophosphate, the concentrations of Ala and AlT were positively correlated with pH; while, in drinking water with orthophospbate, the concentrations of Ala and AlT were negatively correlated with pH. The addition of orthophosphate salts in the drinking water treatment process would be an effective method for aluminum control in pH range 6.5-8.2. 展开更多
关键词 aluminum species geographic information system ORTHOPHOSPHATE water quality
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The application of Yangtze Estuary Tidal Wetlands Geographic Information System 被引量:1
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作者 WANGJun CHENZhenlou +2 位作者 XUShiyuan WANGDongqi LIUJie 《Journal of Geographical Sciences》 SCIE CSCD 2005年第2期155-166,共12页
Yangtze Estuary Tidal Wetlands Geographic Information System (YETWGIS) is a comprehensive software system for environmental management and decision of Yangtze estuary tidal wetlands. Based on MapObjects components tec... Yangtze Estuary Tidal Wetlands Geographic Information System (YETWGIS) is a comprehensive software system for environmental management and decision of Yangtze estuary tidal wetlands. Based on MapObjects components technology, Data Mining technology, mathematical modeling method and Visual Basic language, this software system has many functions such as displaying, editing, querying and searching, spatial statistics and analysis, thematic map compiling, and environmental quality evaluation. This paper firstly outlined the system structure, key techniques, and achieving methods of YETWGIS, and then, described the core modules (the thematic map compiling module and environmental quality evaluation model module) in detail. In addition, based on information entropy model, it thoroughly discussed the methods of environmental quality evaluation and indicators' weight calculation. Finally, by using YETWGIS, this paper analyzed the spatial distribution characteristics of Heavy Metal and Persistent Organic Pollutants (POPs) of the Yangtze estuary tidal wetlands in 2002, and evaluated the environmental quality of the Yangtze estuary tidal wetlands in 2003. 展开更多
关键词 Yangtze estuary tidal wetland geographic information system components technology information entropy model
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Epidemiologic Evolution Platform Using Integrated Modeling and Geographic Information System 被引量:1
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作者 Adrian Brezulianu Oana Geman +3 位作者 Muhammad Arif Iuliana Chiuchisan Octavian Postolache Guojun Wang 《Computers, Materials & Continua》 SCIE EI 2021年第5期1645-1663,共19页
At the international level, a major effort is being made to optimizethe flow of data and information for health systems management. The studiesshow that medical and economic efficiency is strongly influenced by the le... At the international level, a major effort is being made to optimizethe flow of data and information for health systems management. The studiesshow that medical and economic efficiency is strongly influenced by the levelof development and complexity of implementing an integrated system of epidemiological monitoring and modeling. The solution proposed and describedin this paper is addressed to all public and private institutions involved inthe fight against the COVID-19 pandemic, using recognized methods andstandards in this field. The Green-Epidemio is a platform adaptable to thespecific features of any public institution for disease management, based onopen-source software, allowing the adaptation, customization, and furtherdevelopment of “open-source” applications, according to the specificities ofthe public institution, the changes in the economic and social environment andits legal framework. The platform has a mathematical model for the spreadof COVID-19 infection depending on the location of the outbreaks so thatthe allocation of resources and the geographical limitation of certain areascan be parameterized according to the number and location of the real-timeidentified outbreaks. The social impact of the proposed solution is due to theplanned applications of information flow management, which is a first stepin improving significantly the response time and efficiency of people-operatedresponse services. Moreover, institutional interoperability influences strategicsocietal factors. 展开更多
关键词 Epidemiology evolution service-oriented architecture PANDEMIC geographic information system epidemiological modeling
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Mapping potential areas for groundwater storage in the High Guir Basin(Morocco):Contribution of remote sensing and geographic information system 被引量:1
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作者 Abderrahime Nouayti Driss Khattach +1 位作者 Mohamed Hilali Nordine Nouayti 《Journal of Groundwater Science and Engineering》 2019年第4期309-322,共14页
Identification of water potential areas in arid regions is a crucial element for the enhancement of their water resources and socio-economic development. In fact, water resources system-planning can be used to make va... Identification of water potential areas in arid regions is a crucial element for the enhancement of their water resources and socio-economic development. In fact, water resources system-planning can be used to make various decisions and implement manage- ment of water resources policies. The purpose of this study is to identify groundwater sto- rage areas in the high Guir Basin by implementing Geographic Information System (GIS) and Remote Sensing methods. The required data for this study can be summarized into five critical factors: Topography (slope), lithology, rainfall, rock fracture and drainage. These critical factors have been converted by the GIS into thematic maps. For each cri- tical parameter, a coefficient with weight was attributed according to its importance. The map of potential groundwater storage areas is obtained by adding the products (coeffi- cient × weight) of the five parameters. The results show that 50% to 64% of the total area of the High Guir Basin is potentially rich in groundwater, where most of fracture systems are intensely developed. The obtained results are validated with specific yield of the aqui- fer in the study area. It is noted that there is a strong positive correlation between excel- lent groundwater potential zones with high flows of water points and it diminishes with low specific yield with poor potential zones. 展开更多
关键词 High Guir Basin Groundwater storage Remote Sensing Potential assessment geographic information system
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Identification of landing sites for rescue helicopters in mountains with use of Geographic Information Systems
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作者 KROH Pawe? 《Journal of Mountain Science》 SCIE CSCD 2020年第2期261-270,共10页
Helicopters are often used in mountain rescue both for rescuers moving in the area of accidents and for evacuating victims, but in steep or forested terrain finding a landing place can be problematic. The main aim of ... Helicopters are often used in mountain rescue both for rescuers moving in the area of accidents and for evacuating victims, but in steep or forested terrain finding a landing place can be problematic. The main aim of this research is to use Digital Elevation Model(DEM) and cartographic database analysis to select locations that can be used as landing site for the rescue helicopters. Methods were based on GIS analysis;both raster and vector data were used for identifying touchdown points for rescue helicopters. Based on DEM data, locations with a low slope gradient were identified;topographic vector data were used for identifying unforested sites. Then buffer zones for buildings and power lines were excluded, and it was checked whether the areas had any topographic features that prevented helicopter landings. The findings were verified on an orthophotomap. In result, GIS analyses have selected 1232 polygons that fulfilled initial criteria. Their verification on orthophotomap has shown that only 55% of them could be potentially used as landing site. Landing sites can be found mainly on side ridges of mountain ranges and in valley beds, when those on ridges are most important in this research. The greatest difficulties and methodological challenges are posed by: identification of sites having a shape which prevents landing, the obsolescence of data due to environment dynamics, the presence of features that are not shown on maps but prevent helicopter landings. A map of landing sites is a very useful tool to conduct rescue operations, but each use of a given landing site requires both in-field and numerical verification. The analysis demonstrated that GIS toolsare useful in pre-planning of rescue missions, and also showed that such data must be kept up-to-date and in-field verification is needed continuously, the more so as it plays an important role in ensuring the safety of rescuers and victims. 展开更多
关键词 Helicopter mountain rescue geographic information systems Digital Elevation Model Topographic databases Landing sites Geoinformation
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The Application of Geographic Information System on Telecommunication Cable Management System
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作者 He Hong bo,Wang Wen jun, Zeng Qiao ming College of Information, Changsha Railway University, Changsha 410075, China 《Wuhan University Journal of Natural Sciences》 CAS 2001年第Z1期482-485,共4页
Geographic Information System (GIS) is a computer system to manage the geographically distributed data. It combines the process of geographic information and attribute information. Telecommunication bureau has great r... Geographic Information System (GIS) is a computer system to manage the geographically distributed data. It combines the process of geographic information and attribute information. Telecommunication bureau has great requirements for GIS and corresponding software platforms due to the speciality of the telecommunication system. The design ideas, solutions and basic functions of the telecommunication GIS for the cable design and maintenance are discussed. 展开更多
关键词 DESIGN maintenance geographic information system
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Function Analyses of Geographic Information System on Rural Distribution Network
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作者 FANG Junlong FAN Yongcun +1 位作者 ZHANG Chunmei GU Shumin 《Journal of Northeast Agricultural University(English Edition)》 CAS 2006年第2期178-181,共4页
With the actuality and characteristic and requirement of rural power enterprise distribution network management, this article introduced the function of geographic information system on the framework of distribution n... With the actuality and characteristic and requirement of rural power enterprise distribution network management, this article introduced the function of geographic information system on the framework of distribution network, in order to develop rural distribution network. 展开更多
关键词 function analyses geographic information system distribution network
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Using Geographic Information Systems (GIS) for Targeted National Recruitment of Community-Dwelling Caregivers Managing Dementia-Related Behavioral and Psychological Symptoms: A Recruitment Approach for a Randomized Clinical Trial
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作者 Danny L. Scerpella Nicole G. Bouranis +5 位作者 Melinda J. Webster Maria Dellapina Sokha Koeuth Lauren J. Parker Helen C. Kales Laura N. Gitlin 《Journal of Geographic Information System》 2021年第3期302-317,共16页
Over 16 million caregivers of people living with dementia require support in a range of issues, including self-care, disease education, and guidance for how to manage behavioral and psychological symptoms of dementia ... Over 16 million caregivers of people living with dementia require support in a range of issues, including self-care, disease education, and guidance for how to manage behavioral and psychological symptoms of dementia (BPSD). Non-pharmacological interventions are needed to address these areas, and online applications have been shown to be safe and effective. To ensure the efficacy of such interventions, racially, ethnically, geographically, and socioeconomically diverse participants must be recruited to increase the generalizability of study outcomes. This protocol paper describes a recruitment plan using Geographic Information Systems (GIS) to reach a representative sample of caregivers across the United States for a national Phase III clinical study. Using publicly available census data from the American Community Survey (ACS), combined with location data for local aging resources such as Area Agencies on Aging (AAA), recruitment will be derived from data analysis conducted in ESRI ArcGIS v10.7.1. Datasets including age, gender, income, and education will be assessed nationally at the county and census tract spatial scale in a nine-step process to develop recruitment priority areas containing high concentrations of eligible participants living in the community. Overall, the current protocol will demonstrate the value of GIS in tailoring targeted outreach strategies to recruit community-dwelling populations through local resource institutions. This novel approach may have far-reaching implications in future recruitment initiatives and help to secure racially/ethnically diverse samples. 展开更多
关键词 geographic information systems RECRUITMENT Clinical Trial GIS Dementia or Caregiving
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Combining Geographic Information Systems for Transportation and Mixed Integer Linear Programming in Facility Location-Allocation Problems
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作者 Silvia Maria Santana Mapa Renato da Silva Lima 《Journal of Software Engineering and Applications》 2014年第10期844-858,共15页
In this study, we aimed to assess the solution quality for location-allocation problems from facilities generated by the software TransCAD&reg;?, a Geographic Information System for Transportation (GIS-T). Such fa... In this study, we aimed to assess the solution quality for location-allocation problems from facilities generated by the software TransCAD&reg;?, a Geographic Information System for Transportation (GIS-T). Such facilities were obtained after using two routines together: Facility Location and Transportation Problem, when compared with optimal solutions from exact mathematical models, based on Mixed Integer Linear Programming (MILP), developed externally for the GIS. The models were applied to three simulations: the first one proposes opening factories and customer allocation in the state of Sao Paulo, Brazil;the second involves a wholesaler and a study of location and allocation of distribution centres for retail customers;and the third one involves the location of day-care centers and allocation of demand (0 - 3 years old children). The results showed that when considering facility capacity, the MILP optimising model presents results up to 37% better than the GIS and proposes different locations to open new facilities. 展开更多
关键词 geographic information systems for Transportation Location-Allocation Problems Mixed Integer Linear Programming TRANSPORTATION TransCAD^(█)
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Regional groundwater resources development suitability assessment model with geographic information system
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《Global Geology》 1998年第1期80-80,共1页
关键词 Regional groundwater resources development suitability assessment model with geographic information system
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Bioenergy Crops as a Promising Alternative to Fossil Fuels in Louisiana: A Geographic Information System (GIS) Perspective
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作者 Yaw A. Twumasi Zhu H. Ning +14 位作者 John B. Namwamba Abena B. Asare-Ansah Edmund C. Merem Harriet B. Yeboah Judith Oppong Matilda Anokye Diana B. Frimpong Priscilla M. Loh Julia Atayi Rechael N. D. Armah Caroline Y. Apraku Opeyemi I. Oladigbolu Cynthia C. Ogbu Leah W. Njeri Joyce McClendon-Peralta 《Journal of Sustainable Bioenergy Systems》 CAS 2022年第4期57-81,共25页
Rising greenhouse gas emissions are causing climate change, and the world’s focus has shifted to the need to reduce our reliance on fossil fuels. There has been a rise in the published literature on the utilization o... Rising greenhouse gas emissions are causing climate change, and the world’s focus has shifted to the need to reduce our reliance on fossil fuels. There has been a rise in the published literature on the utilization of crops for bioenergy production in Louisiana. However, very few scholarly documents have used Geographic Information Systems (GIS) to map the distribution of potential bioenergy crops in Louisiana. This study seeks to fill the void by evaluating the potential of bioenergy crops in Louisiana for energy production using GIS. Given this objective, the agricultural census data for 1999, 2009, 2019, and 2020 obtained from the U.S. Department of Agriculture were used in the analysis. The quantities of various crops produced in the state were loaded into an attribute table and joined to a shapefile using ArcGIS software. The symbology tool’s graduated option was used to create five maps representing each of the bioenergy crops in Louisiana. The findings of the GIS analysis show that some of the parishes, such as Franklin produced the most bushels of corn (13,795,416), Iberia produced the most tons of sugarcane (1,697,980), East Carroll produced the most bushels of soybean (8,237,991), Tensas harvested the most bales of cotton (80,898) and Avoyelles produced the most bushels of sorghum (630,694). The abundance and availability of crops as raw materials for energy production will translate into lower prices in terms of energy use, making bioenergy crops a promising alternative to fossil fuels. In addition, gasoline price data from 1993-2022 was obtained from U.S. Energy Information Administration. A regression model for the average annual gasoline price over the years was constructed. The results show that the average annual gasoline price variation with respect to years is statistically significant (p 0.05). This suggests that gasoline prices will generally rise despite a price drop over the years. The paper concludes by outlining policy recommendations in the form of assessing the availability and viability of other crop types, such as wheat, oats, and rice, for energy production in the state. 展开更多
关键词 Bioenergy Crops BIOMASS Fossil Fuel GASOLINE geographic information Sys-tem (GIS) Regression Analysis LOUISIANA
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Enhanced geographic information system-based mapping of local climate zones in Beijing, China 被引量:7
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作者 QUAN JinLing 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2019年第12期2243-2260,共18页
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 l... 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. 展开更多
关键词 geographic information system(GIS) remote sensing local climate zone(LCZ) land surface temperature urban morphology
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Assessing the Response of Seasonal Variation of Net Primary Productivity to Climate Using Remote Sensing Data and Geographic Information System Techniques in Xinjiang 被引量:2
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作者 Dai-Liang Peng Jing-Feng Huang +2 位作者 Cheng-Xia Cai Rui Deng Jun-Feng Xu 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2008年第12期1580-1588,共9页
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 importan... 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. 展开更多
关键词 CLIMATE geographic information system techniques net primary productivity remote sensing seasonal variation serial correlation ageing time lag.
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Exploring spatial relationships between stream channel features,water depths and flow velocities during flash floods using HEC-GeoRAS and Geographic Information Systems 被引量:1
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作者 Miguel LEAL Eusébio REIS Pedro Pinto SANTOS 《Journal of Geographical Sciences》 SCIE CSCD 2022年第4期757-782,共26页
Water depths and flow velocities decisively influence the damage caused by flash floods.Geographic Information System(GIS)is a powerful and useful tool,allowing the spatial analysis of results obtained by hydraulic mo... Water depths and flow velocities decisively influence the damage caused by flash floods.Geographic Information System(GIS)is a powerful and useful tool,allowing the spatial analysis of results obtained by hydraulic modelling,namely from the HEC-RAS/HEC-GeoRAS software.The GIS spatial analysis performed in this study seeks to explain and quantify the spatial relationships between the stream channel features and flow components during flash flood events.Despite these relationships are generically known,there are few studies exploring this subject in different geographic contexts.A 1D hydraulic model was applied in a small watershed in Portugal,providing good results in the definition of floodable areas,water depths and longitudinal velocities.No direct relationship was found between water depths and velocities in the floodable areas;however,negative strong correlations were found between the two flow components along the stream centerlines.Bed slope,channel and flood width,and roughness prove to be highly relevant on the longitudinal variations of water depths and velocities and on the location of maximum values.Increasing peak discharges and return periods(R;)can change the relationships between water depths and velocities at the same location.Results can be improved with more accurate elevation data for stream channels and floodplains. 展开更多
关键词 flash floods water depth flow velocity geographic information systems(GIS) spatial analysis
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Evaluation of tobacco soil fertility suitability of the Sanmenxia area, China, based on geographic information systems 被引量:1
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作者 Haisheng CHEN Yongfeng YANG +1 位作者 Guoshun LIU Zhengxian TONG 《Frontiers in Biology》 CSCD 2009年第4期453-459,共7页
The growth of flue-cured tobacco is sensitive to changes in environmental conditions.Excellent tobacco leaf production is strictly restricted by regional cultivated lands.For the purpose of reasonable utilization and ... The growth of flue-cured tobacco is sensitive to changes in environmental conditions.Excellent tobacco leaf production is strictly restricted by regional cultivated lands.For the purpose of reasonable utilization and scientific management of Sanmenxia tobacco fields,it is meaningful to evaluate the soil fertility suitability of tobacco crops quantitatively and objectively.In this study,the global positioning system(GPS)technology was used to obtain sample point information automatically.Based on the analysis of fertility properties of soil samples collected from the Sanmenxia tobacco planting regions in Henan Province,we present the index system of soil fertility suitability for tobacco crops.The integrated evaluation of soil fertility suitability was studied with six indices,including organic matter,pH value,available nitrogen(N),available phosphorus(P),available potassium(K),and chlorine(Cl–1)content of surface soil.The subjective grade value was calculated according to S-type and parabola-type functions of the effect of evaluation factors on tobacco crops.Further,the weight value of soil fertility suitability indices was calculated by the method of Hiberarchy analysis.The soil fertility suitability level was evaluated and classified.The suitability map of the Sanmenxia tobacco planting regions in Henan Province was then drawn with the geographic information system(GIS)software mapGIS.It was found that highly suitable fields were mainly distributed in the high mountains in the Southwestern part of the investigated regions where soil pH value and the contents of organic matter were medium,but the contents of available P and available K were higher,accounting for 79.36% of the whole area.Suitable fields were 17% of the whole area,mainly distributed in the middle part of the investigated regions where soil pH value was higher.Unsuitable fields existed in the northern-east and middle part of the Sanmenxia where the contents of soil Cl^(–)was very high,accounting for 3.51%of the whole regions. 展开更多
关键词 geographic information system TOBACCO eva-luation factors weight value soil fertility suitability
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TThe Geographic Information Grid System Based on Mobile Agent
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作者 SHEN Zhi-dong TONG Qiang +1 位作者 HUANG Xian-feng WANG Hua-min 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第1期304-308,共5页
We analyze the deficiencies of current application systems, and discuss the key requirements of distributed Geographie Information serviee (GIS), We construct the distributed GIS on grid platform. Considering the fl... We analyze the deficiencies of current application systems, and discuss the key requirements of distributed Geographie Information serviee (GIS), We construct the distributed GIS on grid platform. Considering the flexibility and efficiency, we integrate the mobile agent technology into the system. We propose a new prototype system, the Geographic Information Grid System (GIGS) based on mobile agent. This system has flexible services and high performance, and improves the sharing of distributed resources. The service strategy of the system and the examples are also presented. 展开更多
关键词 GRID geographic information system (GIS) spatial data mobile agent
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Application of Geographic Information Systems to Analyses and Modeling of Hydrocarbons Anomaly in Yakla,North Tarim Basin,Xinjiang,China
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作者 Mohammad Reza Hosseinnejad Mohammad Ebrahimi Faculty of Earth Sciences, China University of Geosciences, Wuhan 430074 《Journal of Earth Science》 SCIE CAS CSCD 1998年第2期45-51,共7页
Yakla area is a very important and typical region in North Tarim, because it is the region that leads to a breakthrough in North Tarim oil/gas exploring. Therefore, a lot of exploration work has been already carried o... Yakla area is a very important and typical region in North Tarim, because it is the region that leads to a breakthrough in North Tarim oil/gas exploring. Therefore, a lot of exploration work has been already carried out in the area aiming at assessing the hydrocarbon anomaly and some techniques for anomaly delineation are being suggested. Yakla covers about 312 km 2 and lies 20 km south to Luntai Kuche road and displays as a long rectangular, with the length of 24 km in ENE and the width of 13 km in WSW. The surface is desert covered with saline akali, sand ribbon and sand dune. Samples collected from Yakla were analyzed for their hydrocarbon mass fractions and the spatial distribution of the concentrations of selected hydrocarbons C 1, C 2, C 3, i C 4, n C 4, i C 5, n C 5 and UF365 were estimated from these data sets. Multivariate statistical techniques including Kriging, moving average, factor analyses, cluster analyses and furrier filtering are used. The statistical techniques, spatial data analysis and transformation capabilities of geographic information systems, combined with geophysical and geological data, helped the authors to identify the hydrocarbon anomaly in Yakla. 展开更多
关键词 hydrocarbon anomaly geographic information systems (GIS) Yakla Xinjiang.
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