GML is becoming the de facto standard for electronic data exchange among the applications of Web and distributed geographic information systems. However, the conventional query languages (e. g. SQL and its extended v...GML is becoming the de facto standard for electronic data exchange among the applications of Web and distributed geographic information systems. However, the conventional query languages (e. g. SQL and its extended versions) are not suitable for direct querying and updating of GML documents. Even the effective approaches working well with XML could not guarantee good results when applied to GML documents. Although XQuery is a powerful standard query language for XML, it is not proposed for querying spatial features, which constitute the most important components in GML documents. We propose GQL, a query language specification to support spatial queries over GML documents by extending XQuery. The data model, algebra, and formal semantics as well as various spatial Junctions and operations of GQL are presented in detail.展开更多
This paper presents a development o f the extended Cellular Automata9CA),based on relational databases(RDB),to model dynamic interactions amon g spatial objects.The integration o f Geographical Information System(GIS)...This paper presents a development o f the extended Cellular Automata9CA),based on relational databases(RDB),to model dynamic interactions amon g spatial objects.The integration o f Geographical Information System(GIS)and CA has the great advantage of simu lationg geographical processes.But standard CA has some restrictions i n cellular shape and neighbourhood and neighbour rules,which restrict the CA’ s ability to simulate complex,real world environ-ments.This paper discusses a cell’ s spatialrelationbasedonthe spatialobject’ s geometricalandmon -geometricalc haracter-istics,and extends the cell’ s neighbour definition,and considers that the cell’ s neighbour lies in the forms of not on ly spa-tial adjacency but also attribute co rrelation.This paper then puts forw ard that spatial relations between t wo different cells can be divided into three types,including spatial adjacency,neighbour hood and complicated separation.Ba sed on tradition-al ideas,it is impossible to settle CA’ s restrictions completely.RDB -based CA is an academic experiment,in which some fields ard desighed to describe the essential information needed to define and select a cell’ s neighbour.The culture innovation diffusion system has mul tiple forms of space diffusion and in herited characteristics that the RD B -based CA is capable of simulating more effectiv ely.Finally this paper details a successful case study on the diffusion o f fashion wear trends.Compared to the original CA,the RDB -based CA is a more natural and efficient representation of human k nowl-edge over space,and is an effective t ol in simulation complex systems that have multiple forms of spatial diff usion.展开更多
With the degeneration of environment and acceleration of urbanization,human environment has attracted great attention worldwide.This paper sets up the Human Settlements Environment Index(HEI) model and evaluates the n...With the degeneration of environment and acceleration of urbanization,human environment has attracted great attention worldwide.This paper sets up the Human Settlements Environment Index(HEI) model and evaluates the natural environment suitability for Human Settlements in China based on GIS technology.The results show that the HEI of China decreases from southeast to northwest in general,HEI is significantly correlated with population density at grid size and the correlation coefficient(r) between them reaches 0.93,which indicates that natural environment suitability for Human Settlements has a significant influence on population distribution.Most people in China mainly concentrate in areas with high natural environment suitability.The total suitable area is 430.47×104 km2,which accounts for nearly 45% of the total land area in China,while the proportion of people living in the area reaches 96.56%.With a population density of 18 people per square kilometer,the critical area is the transitional region for people to live in China.The critical area covers 225.11×104 km2 with a population of 41.12 million.The non-suitable area covers 304.42×104 km2 with a population of only 2.49 million.展开更多
Based on an analysis of the characteristics of the Forest Resources Management Information System of each development phase, and consideration of the technical trend in Geographic Information System (GIS) in the Inter...Based on an analysis of the characteristics of the Forest Resources Management Information System of each development phase, and consideration of the technical trend in Geographic Information System (GIS) in the Internet Age, this paper explores the importance and the feasibility of setting up Forest Resources Management Information System based on the WEBGIS. At the same time, based on the experience of our study, the paper explores the function, structure and method of developing the Forest Resources Management Information System based on WEBGIS. With the technology of WEBGIS, the Forest Resources Management Information System with data from Huoditang Farm was set up, which makes a great impact on forest resources management. So setting up the Forest Resources Management Information System based on WEBGIS is a trend of forest resources management. In the course of setting up this system, we must pay attention to following questions: 1) unify data standard and information encoding; 2) change mind.展开更多
This study examines the socio-spatial context of uneven development and the residential accessibility of green space in Dalian of Liaoning Province, China. The social fairness was analyzed with a community scale as th...This study examines the socio-spatial context of uneven development and the residential accessibility of green space in Dalian of Liaoning Province, China. The social fairness was analyzed with a community scale as the basis. We combined social scientific methods with a GIS method using a behavior accessibility model from the perspectives of fairness of urban green space allocation based on social geography, geographic information science, management science and many other related discipline theories. The results show that: 1) Most of the urban green space distribution presents an unbalanced phenomenon, and it does not match with the population distribution; 2) We found some differences in the accessibility of the population with different attributes and opportunities to use and enjoy the urban green spaces, mainly due to: the dual social and spatial attributes of the residents and the serious stratum differentiation generated were the internal causes; the residential space differentiation and the pursuit of economic and real estate development were the direct causes; and unreasonable planning, in regard to the fact that government policies did not give consideration to efficiency and fairness, was also an important factor.展开更多
Precision Agriculture, also known as Precision Farming, or Prescription Farming, is a modern agriculture technology system, which brings ' precision' into agriculture system. All concepts of Precision Agricult...Precision Agriculture, also known as Precision Farming, or Prescription Farming, is a modern agriculture technology system, which brings ' precision' into agriculture system. All concepts of Precision Agriculture are established on the collection and management of variable cropland information. As the tool of collecting, managing and analyzing spatial data, GIS is the key technology of integrated Precision Agriculture system. This article puts forward the concept of Farmland GIS and designs Farmland GIS into five modules, and specifies the functions of the each module, which builds the foundation for practical development of the software. The study and development of Farmland GIS will propel the spreading of Precision Agriculture technology in China.展开更多
A methodology is developed for interactive risk assessment of physical infrastructure and spatially distributed response systems subjected to debris flows.The proposed framework is composed of three components,namely ...A methodology is developed for interactive risk assessment of physical infrastructure and spatially distributed response systems subjected to debris flows.The proposed framework is composed of three components,namely geotechnical engineering,geographical information systems and disaster management.With the integration of slope stability analysis,hazard scenario and susceptibility,geological conditions are considered as temporary static data,while meteorological conditions are treated as dynamic data with a focus on typhoons.In this research,the relevant parameters required for database building are defined,and the procedures for building the geological database and meteorological data sets are explained.Based on the concepts and data sets,Nantou and Hualien in Taiwan are used as the areas for case studies.展开更多
The history, current situation, and development trend of GIS (Geographic Information System) applied in the forest resources management were discussed in this paper. On the basis of geographic spatial characteristics ...The history, current situation, and development trend of GIS (Geographic Information System) applied in the forest resources management were discussed in this paper. On the basis of geographic spatial characteristics of forest resources data, a component geographic information system (ComGIS) was developed for forest resources management. The system embeds a GIS ActiveX control MapObjects (Inc. ESRI) on Visual C++ platform. System design, data organization and achieving way were studied and expatiated by taking Xigangzi Forestry Centre as study object. The system has many useful functions,, such as adding and display of various map layers, zoom of map by wheeling mouse, attribute and spatial data querying, map auto roaming, features rendering based on the spatial trait of data, label controlling through attribute data band with vector graph, as well as output of 'Column chart' for showing the result of statistics. At the same time, parts of source codes are attached.展开更多
In Pakistan,the solar analogue has been addressed but its surface geographical parameterization has given least attention.Inappropriate density of stations and their spatial coverage particularly in difficult peripher...In Pakistan,the solar analogue has been addressed but its surface geographical parameterization has given least attention.Inappropriate density of stations and their spatial coverage particularly in difficult peripheral national territories,little or no solar radiation data,non-satisfactory sunshine hours data,and low quality of ground observed cloud cover data create a situation in which the spatial modeling of Extraterrestrial Solar Radiation(ESR) and its ground parameterization got sufficient scope.The Digital Elevation Model (DEM) input into Geographic Information System (GIS) is a compatible tool to demonstrate the spatial distribution of ESR over the rugged terrains of the study domain.For the first time,distributed modeling of ESR is done over the rugged terrains of Pakistan,based on DEM and ArcGIS..Results clearly depict that the complex landforms profoundly disrupt the zonal distribution of ESR in Pakistan.The screening impact of topography is higher on spatial distribution of ESR in winter and considerably low in summer.The combined effect of topography and latitude is obvious.Hence,the model was further testified by plotting Rb (ratio of ESR quantity over rugged terrain against plane surface) against azimuth at different latitudes with different angled slopes.The results clearly support the strong screening effect of rugged terrain through out the country especially in Himalayas,Karakoram and Hindukush (HKH),western border mountains and Balochistan Plateau.This model can be instrumental as baseline geospatial information for scientific investigations in Pakistan,where substantial fraction of national population is living in mountainous regions.展开更多
On the study of the basic characteristics of geological objects and the special requirement for computing 3D geological model, this paper gives an object-oriented 3D topologic data model. In this model, the geological...On the study of the basic characteristics of geological objects and the special requirement for computing 3D geological model, this paper gives an object-oriented 3D topologic data model. In this model, the geological objects are divided into four object classes: point, line, area and volume. The volume class is further divided into four subclasses: the composite volume, the complex volume, the simple volume and the component. Twelve kinds of topological relations and the related data structures are designed for the geological objects.展开更多
Integrating the theory of distributed virtual geographic environment (DVGE) and high level architecture(HLA), the architecture of DVGE based on HLA is designed. The data flow and the object models of the architecture ...Integrating the theory of distributed virtual geographic environment (DVGE) and high level architecture(HLA), the architecture of DVGE based on HLA is designed. The data flow and the object models of the architecture are also discussed. The architecture basically meets the need of DVGE in real-time communication, distribution, collaboration, reusing and interoperation, expansion, and standard.展开更多
ComGIS is the mainstream of developing GIS currently.Developing Geographic Information System with the technology of components can reduce the difficulties of developing,improving the developing efficiency and enhanci...ComGIS is the mainstream of developing GIS currently.Developing Geographic Information System with the technology of components can reduce the difficulties of developing,improving the developing efficiency and enhancing the flexibility and opening of system.ArcObjects(AO) is based on the technology of COM,and ArcGIS Engine(AE) is a set of embedded AO which can extend to various platforms.Compared with AO,ArcGIS Engine can shorten the period of developing and improve the efficiency greatly.Having introduced the techniques of ArcObjects and ArcGIS Engine,we offer the method of developing GIS with Visual Basic and ArcGIS Engine with Oil and Gas Geologic Information System.展开更多
Background: Built environments that are designed to provide accessible, attractive, and convenient locales promote regular physical activity(PA).Norway has great variability in its geographic, natural, and built envir...Background: Built environments that are designed to provide accessible, attractive, and convenient locales promote regular physical activity(PA).Norway has great variability in its geographic, natural, and built environment features. Urban areas have well-developed built environment features, whereas the rural areas are less walkable and this may influence the mode of transport. In general, active transport is more common in urban centers. Further, public transportation is more developed in urban areas, whereas motorized transport may be more widespread in the rural areas. Despite this, in Sogn & Fjordane, a rural county in western Norway, high PA levels are frequently observed. Thus, the aims of this study were to(1) explore perceived built environment features and characterize their associations with objectively measured PA levels in Norwegian adults and(2) explore the differences in these correlates between Sogn & Fjordane and the rest of Norway.Methods: In this cross-sectional study, participants used questionnaires to rate perceptions of their built environments, and their PA was objectively measured for 7 consecutive days using the Acti Graph GT1 M accelerometer. There were 972 Norwegian adults who were included in the study. The average age was 46.9 ± 6.5 years and 43.8% of participants were men. Data were analyzed using multiple linear regression.Results: Total PA and moderate-to-vigorous physical activity(MVPA) were both associated with perceived walkability, the community perception score, and active transport for commuting(all p ≤ 0.004). We also observed geographic-area-specific associations: the community perception score was negatively associated with total PA and MVPA in the rest of Norway(p ≤ 0.012) but not in Sogn & Fjordane. Public transport for commuting was positively associated with MVPA in Sogn & Fjordane(p = 0.03) but not in the rest of Norway.Conclusion: Total PA level and MVPA were associated with built environment factors, such as perceptions of community, perceived walkability,and engaging in active transport for commuting. Geographic differences in the PA correlates were observed, and thus, locally customized environmental population approaches aimed at increasing PA levels may be essential complements to individual behavior and lifestyle strategies.Further, objective measures of Norwegian built environments, such as geographic information system data, and validated walk-and bike-scores would advance the field.展开更多
Knowledge and management of soil pH, particularly soil acidity across spatially variable soils is important, although this is greatly ignored by farmers. The objective of the study was to evaluate in-field spatial var...Knowledge and management of soil pH, particularly soil acidity across spatially variable soils is important, although this is greatly ignored by farmers. The objective of the study was to evaluate in-field spatial variability of soil pH, and compare the efficiency of managing soil pH through site-specific method vs. uniform lime application. The study was conducted on three sites with study sites I and II (23°50' S; 29°40' E), and study sites IIl (23°59' S; 28°52' E) adjacent to each other in the semi-arid regions of the Limpopo Province, South Africa. Soil samples were taken in four replicates from geo-referenced locations on a regular grid of 30 m. Soils were analyzed for pH, and SMP buffer pH. Soil maps were produced with Geographic Information System (GIS) software, and soil pH datasets were interpolated using a geostatistical tool of inverse distance weighing (IDW). Soil pH in the fields varied from 3.93 to 7.00. An excess amount of lime as high as 30 t/ha under uniform lime application were recorded. These recommendations were in excess on field areas that needed little or no lime applications. Again, there was an under applications of lime as much as 35 t/ha for uniform liming applications. This under- and over-recommendations of lime based on average soil pH values suggests that uniform soil acidity correction and soil pH management strategy is not an appropriate strategy to be adopted in these fields with spatially variable soils. The field can be divided into lime application zones of (1) high rates of lime, (2) low rates of lime and (3) areas that requires no lime at all so that lime rates are applied per zone. A key to site-specific soil acidity correction with lime is to reach ideal soil pH for the crop in all parts of the field.展开更多
Regional core cities are the growth poles for regional economic development, thus the issue about efficient urbanization pattern has always become a hot spot among researchers and policy makers. The Spatial Economy ca...Regional core cities are the growth poles for regional economic development, thus the issue about efficient urbanization pattern has always become a hot spot among researchers and policy makers. The Spatial Economy can be employed to improve it. Nevertheless, there actually exists an obvious gap between its theoretical models and the empirical simulation. To do so, this paper modifies the measurement of initial geographical advantages Stelder gave, and implements the empirical analyses of urban distribution in Zhejiang during the period of 1980-1990 by means of computer simulations in GIS environment. There are several interesting results achieved in this process. Firstly, given the values of parameters (transport cost is r, substitution elasticity of manufacturing sector p, and income share of spending on manufacture δ), initial geographical advantages have the different impacts on urban systems, namely, urban locations, numbers and sizes over time across space. Secondly, the cities were distributed without any overlay in geographical space, which makes the patterns of urbanization generate the largest possible economic efficiencies. Thirdly, the urban systems-the location, number and size of Cities-from the simulation of the study area are suitable for the actual social and economic situations in the real world during the testing periods. Such results may have substantial implications for the policy how to choose the way of urbanization in a region.展开更多
Using GIS, GPS, GPRS and RFID, a dynamic information management system of digital mining in an open pit was designed and developed.A linear programming model was set up in a practical application.By the model, the sys...Using GIS, GPS, GPRS and RFID, a dynamic information management system of digital mining in an open pit was designed and developed.A linear programming model was set up in a practical application.By the model, the system can automatically draw up production plan of ore blending well every day.The system can monitor and dispatch open-pit trucks and shovels well, and can play back their historical paths.It can monitor and control the process of mining production in real time.By RFID, the system can also count the number of trucks'delivery and shovels'loading automatically.Experiments on real scenes show that the performance of this system is stable and can satisfy production standards of mining in open pits.展开更多
Solid waste management aspect is one of the most important challenges facing the local administration in the Govemorate of Najaf. Therefore, this study aims to provide for solid waste management problem by choosing th...Solid waste management aspect is one of the most important challenges facing the local administration in the Govemorate of Najaf. Therefore, this study aims to provide for solid waste management problem by choosing the best locations for the establishment of sanitary landfills in the governorate. In this study, GIS (geographic information system) and MCDA (multi-criteria decision analysis) were used based on 17 environmental, economic and geological criteria converted to input digital map layers. These were urban centres, cemetery, airports, electrical power lines, oil pipes, railways, roads, slope, historical sites, main rivers, industrial areas, religion sites, wells, military area, electrical power plants, nature reserves and national borders to select most importance sites in the govemorate. AHP (analytic hierarchy process) method was used in weighting the criteria used. All layers' maps were graded from 0 (not suitable) to 5 (most suitable) using spatial information scale then SAW (simple additive weighting) method was integrated in GIS used to calculate the suitability index for the studied area. The results indicated that 4.4% of the study region is suitable for landfill siting with grading values greater than 4.0. This included five sites distributed in three qadhaas of governorate.展开更多
Suffering from fragile environment, poor accessibility and infrastructure, as well as social,political and economic marginality, the interprovincial mountain geographical entities are difficult areas for the regional ...Suffering from fragile environment, poor accessibility and infrastructure, as well as social,political and economic marginality, the interprovincial mountain geographical entities are difficult areas for the regional governance in China.By analyzing the spatial patterns and the influencing factors of the interprovincial mountain geographical names(IMGNs), the goal of this research is to clarify the geographical features of IMGNs and offer alternatives for the management of interprovincial mountain regions in China. The spatial visualization,the analysis of spatial agglomeration and the influencing factors of IMGNs were all implemented under a geographical information system. Results showed that there were 6869 IMGNs in China according to the database of "China's Second National Survey of Geographical Names(2014-2018)",including 4209 mountain geographical names, 1684 mountain peak geographical names and 976 the other mountain geographical names. Hunan Province had the largest number of names while Shanghai had the smallest number of names. In addition, the spatial variance of the mountain peak names and the mountain names were larger than that of the other mountain geographical names, and the IMGNs showed a significant clustering phenomenon in the southern part of China. The relative elevation and the population had an impact on the distribution of the IMGNs. The largest number of the names occurred where the relative elevation was between 1000-2000 m and where the population was between 40-50 million. Density of unnamed interprovincial mountain geographical entities declined from west to east in China. The analysis of generic names of different types of IMGNs implied that the naming of IMGNs is inconsistent. Based on these analyses, it is suggested that the government should take the IMGNs as management units, strengthen the naming of unnamed interprovincial mountain geographical entities, standardize the generic names of IMGNs and identify areas of poverty based on the survey of IMGNs.展开更多
基金Funded by the Youth Chengguang Project of Science and Technology of Wuhan City of China(No.20045006071-16)
文摘GML is becoming the de facto standard for electronic data exchange among the applications of Web and distributed geographic information systems. However, the conventional query languages (e. g. SQL and its extended versions) are not suitable for direct querying and updating of GML documents. Even the effective approaches working well with XML could not guarantee good results when applied to GML documents. Although XQuery is a powerful standard query language for XML, it is not proposed for querying spatial features, which constitute the most important components in GML documents. We propose GQL, a query language specification to support spatial queries over GML documents by extending XQuery. The data model, algebra, and formal semantics as well as various spatial Junctions and operations of GQL are presented in detail.
文摘This paper presents a development o f the extended Cellular Automata9CA),based on relational databases(RDB),to model dynamic interactions amon g spatial objects.The integration o f Geographical Information System(GIS)and CA has the great advantage of simu lationg geographical processes.But standard CA has some restrictions i n cellular shape and neighbourhood and neighbour rules,which restrict the CA’ s ability to simulate complex,real world environ-ments.This paper discusses a cell’ s spatialrelationbasedonthe spatialobject’ s geometricalandmon -geometricalc haracter-istics,and extends the cell’ s neighbour definition,and considers that the cell’ s neighbour lies in the forms of not on ly spa-tial adjacency but also attribute co rrelation.This paper then puts forw ard that spatial relations between t wo different cells can be divided into three types,including spatial adjacency,neighbour hood and complicated separation.Ba sed on tradition-al ideas,it is impossible to settle CA’ s restrictions completely.RDB -based CA is an academic experiment,in which some fields ard desighed to describe the essential information needed to define and select a cell’ s neighbour.The culture innovation diffusion system has mul tiple forms of space diffusion and in herited characteristics that the RD B -based CA is capable of simulating more effectiv ely.Finally this paper details a successful case study on the diffusion o f fashion wear trends.Compared to the original CA,the RDB -based CA is a more natural and efficient representation of human k nowl-edge over space,and is an effective t ol in simulation complex systems that have multiple forms of spatial diff usion.
基金National Natural Science Foundation of China,No.40771204No.40801223National Key Technology R&D Program,No.2006BAC18B01
文摘With the degeneration of environment and acceleration of urbanization,human environment has attracted great attention worldwide.This paper sets up the Human Settlements Environment Index(HEI) model and evaluates the natural environment suitability for Human Settlements in China based on GIS technology.The results show that the HEI of China decreases from southeast to northwest in general,HEI is significantly correlated with population density at grid size and the correlation coefficient(r) between them reaches 0.93,which indicates that natural environment suitability for Human Settlements has a significant influence on population distribution.Most people in China mainly concentrate in areas with high natural environment suitability.The total suitable area is 430.47×104 km2,which accounts for nearly 45% of the total land area in China,while the proportion of people living in the area reaches 96.56%.With a population density of 18 people per square kilometer,the critical area is the transitional region for people to live in China.The critical area covers 225.11×104 km2 with a population of 41.12 million.The non-suitable area covers 304.42×104 km2 with a population of only 2.49 million.
文摘Based on an analysis of the characteristics of the Forest Resources Management Information System of each development phase, and consideration of the technical trend in Geographic Information System (GIS) in the Internet Age, this paper explores the importance and the feasibility of setting up Forest Resources Management Information System based on the WEBGIS. At the same time, based on the experience of our study, the paper explores the function, structure and method of developing the Forest Resources Management Information System based on WEBGIS. With the technology of WEBGIS, the Forest Resources Management Information System with data from Huoditang Farm was set up, which makes a great impact on forest resources management. So setting up the Forest Resources Management Information System based on WEBGIS is a trend of forest resources management. In the course of setting up this system, we must pay attention to following questions: 1) unify data standard and information encoding; 2) change mind.
基金Under the auspices of National Natural Science Foundation of China(No.41471140)
文摘This study examines the socio-spatial context of uneven development and the residential accessibility of green space in Dalian of Liaoning Province, China. The social fairness was analyzed with a community scale as the basis. We combined social scientific methods with a GIS method using a behavior accessibility model from the perspectives of fairness of urban green space allocation based on social geography, geographic information science, management science and many other related discipline theories. The results show that: 1) Most of the urban green space distribution presents an unbalanced phenomenon, and it does not match with the population distribution; 2) We found some differences in the accessibility of the population with different attributes and opportunities to use and enjoy the urban green spaces, mainly due to: the dual social and spatial attributes of the residents and the serious stratum differentiation generated were the internal causes; the residential space differentiation and the pursuit of economic and real estate development were the direct causes; and unreasonable planning, in regard to the fact that government policies did not give consideration to efficiency and fairness, was also an important factor.
基金the Knowledge Innovation Project of the Chinese Academy of Sciences(No.NZCX2-412).
文摘Precision Agriculture, also known as Precision Farming, or Prescription Farming, is a modern agriculture technology system, which brings ' precision' into agriculture system. All concepts of Precision Agriculture are established on the collection and management of variable cropland information. As the tool of collecting, managing and analyzing spatial data, GIS is the key technology of integrated Precision Agriculture system. This article puts forward the concept of Farmland GIS and designs Farmland GIS into five modules, and specifies the functions of the each module, which builds the foundation for practical development of the software. The study and development of Farmland GIS will propel the spreading of Precision Agriculture technology in China.
文摘A methodology is developed for interactive risk assessment of physical infrastructure and spatially distributed response systems subjected to debris flows.The proposed framework is composed of three components,namely geotechnical engineering,geographical information systems and disaster management.With the integration of slope stability analysis,hazard scenario and susceptibility,geological conditions are considered as temporary static data,while meteorological conditions are treated as dynamic data with a focus on typhoons.In this research,the relevant parameters required for database building are defined,and the procedures for building the geological database and meteorological data sets are explained.Based on the concepts and data sets,Nantou and Hualien in Taiwan are used as the areas for case studies.
基金This work was supported by Provincial Key Technologies R and D program of Heilongjiang (GC02B608)
文摘The history, current situation, and development trend of GIS (Geographic Information System) applied in the forest resources management were discussed in this paper. On the basis of geographic spatial characteristics of forest resources data, a component geographic information system (ComGIS) was developed for forest resources management. The system embeds a GIS ActiveX control MapObjects (Inc. ESRI) on Visual C++ platform. System design, data organization and achieving way were studied and expatiated by taking Xigangzi Forestry Centre as study object. The system has many useful functions,, such as adding and display of various map layers, zoom of map by wheeling mouse, attribute and spatial data querying, map auto roaming, features rendering based on the spatial trait of data, label controlling through attribute data band with vector graph, as well as output of 'Column chart' for showing the result of statistics. At the same time, parts of source codes are attached.
文摘In Pakistan,the solar analogue has been addressed but its surface geographical parameterization has given least attention.Inappropriate density of stations and their spatial coverage particularly in difficult peripheral national territories,little or no solar radiation data,non-satisfactory sunshine hours data,and low quality of ground observed cloud cover data create a situation in which the spatial modeling of Extraterrestrial Solar Radiation(ESR) and its ground parameterization got sufficient scope.The Digital Elevation Model (DEM) input into Geographic Information System (GIS) is a compatible tool to demonstrate the spatial distribution of ESR over the rugged terrains of the study domain.For the first time,distributed modeling of ESR is done over the rugged terrains of Pakistan,based on DEM and ArcGIS..Results clearly depict that the complex landforms profoundly disrupt the zonal distribution of ESR in Pakistan.The screening impact of topography is higher on spatial distribution of ESR in winter and considerably low in summer.The combined effect of topography and latitude is obvious.Hence,the model was further testified by plotting Rb (ratio of ESR quantity over rugged terrain against plane surface) against azimuth at different latitudes with different angled slopes.The results clearly support the strong screening effect of rugged terrain through out the country especially in Himalayas,Karakoram and Hindukush (HKH),western border mountains and Balochistan Plateau.This model can be instrumental as baseline geospatial information for scientific investigations in Pakistan,where substantial fraction of national population is living in mountainous regions.
文摘On the study of the basic characteristics of geological objects and the special requirement for computing 3D geological model, this paper gives an object-oriented 3D topologic data model. In this model, the geological objects are divided into four object classes: point, line, area and volume. The volume class is further divided into four subclasses: the composite volume, the complex volume, the simple volume and the component. Twelve kinds of topological relations and the related data structures are designed for the geological objects.
基金Funded by the National Natural Science Foundation of China (No.40341011) and the National 863 Program of China(No.2002AA135230)
文摘Integrating the theory of distributed virtual geographic environment (DVGE) and high level architecture(HLA), the architecture of DVGE based on HLA is designed. The data flow and the object models of the architecture are also discussed. The architecture basically meets the need of DVGE in real-time communication, distribution, collaboration, reusing and interoperation, expansion, and standard.
基金Supported by National Oil-gas Project:No XQ-2004-07
文摘ComGIS is the mainstream of developing GIS currently.Developing Geographic Information System with the technology of components can reduce the difficulties of developing,improving the developing efficiency and enhancing the flexibility and opening of system.ArcObjects(AO) is based on the technology of COM,and ArcGIS Engine(AE) is a set of embedded AO which can extend to various platforms.Compared with AO,ArcGIS Engine can shorten the period of developing and improve the efficiency greatly.Having introduced the techniques of ArcObjects and ArcGIS Engine,we offer the method of developing GIS with Visual Basic and ArcGIS Engine with Oil and Gas Geologic Information System.
基金supported by the Sogn & Fjordane County Council, Sparebanken Vest–Visjon Vest, the Norwegian Directorate of Health, Norwegian School of Sport Sciences, and Sogn & Fjordane University College
文摘Background: Built environments that are designed to provide accessible, attractive, and convenient locales promote regular physical activity(PA).Norway has great variability in its geographic, natural, and built environment features. Urban areas have well-developed built environment features, whereas the rural areas are less walkable and this may influence the mode of transport. In general, active transport is more common in urban centers. Further, public transportation is more developed in urban areas, whereas motorized transport may be more widespread in the rural areas. Despite this, in Sogn & Fjordane, a rural county in western Norway, high PA levels are frequently observed. Thus, the aims of this study were to(1) explore perceived built environment features and characterize their associations with objectively measured PA levels in Norwegian adults and(2) explore the differences in these correlates between Sogn & Fjordane and the rest of Norway.Methods: In this cross-sectional study, participants used questionnaires to rate perceptions of their built environments, and their PA was objectively measured for 7 consecutive days using the Acti Graph GT1 M accelerometer. There were 972 Norwegian adults who were included in the study. The average age was 46.9 ± 6.5 years and 43.8% of participants were men. Data were analyzed using multiple linear regression.Results: Total PA and moderate-to-vigorous physical activity(MVPA) were both associated with perceived walkability, the community perception score, and active transport for commuting(all p ≤ 0.004). We also observed geographic-area-specific associations: the community perception score was negatively associated with total PA and MVPA in the rest of Norway(p ≤ 0.012) but not in Sogn & Fjordane. Public transport for commuting was positively associated with MVPA in Sogn & Fjordane(p = 0.03) but not in the rest of Norway.Conclusion: Total PA level and MVPA were associated with built environment factors, such as perceptions of community, perceived walkability,and engaging in active transport for commuting. Geographic differences in the PA correlates were observed, and thus, locally customized environmental population approaches aimed at increasing PA levels may be essential complements to individual behavior and lifestyle strategies.Further, objective measures of Norwegian built environments, such as geographic information system data, and validated walk-and bike-scores would advance the field.
文摘Knowledge and management of soil pH, particularly soil acidity across spatially variable soils is important, although this is greatly ignored by farmers. The objective of the study was to evaluate in-field spatial variability of soil pH, and compare the efficiency of managing soil pH through site-specific method vs. uniform lime application. The study was conducted on three sites with study sites I and II (23°50' S; 29°40' E), and study sites IIl (23°59' S; 28°52' E) adjacent to each other in the semi-arid regions of the Limpopo Province, South Africa. Soil samples were taken in four replicates from geo-referenced locations on a regular grid of 30 m. Soils were analyzed for pH, and SMP buffer pH. Soil maps were produced with Geographic Information System (GIS) software, and soil pH datasets were interpolated using a geostatistical tool of inverse distance weighing (IDW). Soil pH in the fields varied from 3.93 to 7.00. An excess amount of lime as high as 30 t/ha under uniform lime application were recorded. These recommendations were in excess on field areas that needed little or no lime applications. Again, there was an under applications of lime as much as 35 t/ha for uniform liming applications. This under- and over-recommendations of lime based on average soil pH values suggests that uniform soil acidity correction and soil pH management strategy is not an appropriate strategy to be adopted in these fields with spatially variable soils. The field can be divided into lime application zones of (1) high rates of lime, (2) low rates of lime and (3) areas that requires no lime at all so that lime rates are applied per zone. A key to site-specific soil acidity correction with lime is to reach ideal soil pH for the crop in all parts of the field.
基金Under the auspices of Chinese Academy of Philosophy and Social Science (No. 04BJL052), Ministry of Construction of China (No. 06-R1-8)
文摘Regional core cities are the growth poles for regional economic development, thus the issue about efficient urbanization pattern has always become a hot spot among researchers and policy makers. The Spatial Economy can be employed to improve it. Nevertheless, there actually exists an obvious gap between its theoretical models and the empirical simulation. To do so, this paper modifies the measurement of initial geographical advantages Stelder gave, and implements the empirical analyses of urban distribution in Zhejiang during the period of 1980-1990 by means of computer simulations in GIS environment. There are several interesting results achieved in this process. Firstly, given the values of parameters (transport cost is r, substitution elasticity of manufacturing sector p, and income share of spending on manufacture δ), initial geographical advantages have the different impacts on urban systems, namely, urban locations, numbers and sizes over time across space. Secondly, the cities were distributed without any overlay in geographical space, which makes the patterns of urbanization generate the largest possible economic efficiencies. Thirdly, the urban systems-the location, number and size of Cities-from the simulation of the study area are suitable for the actual social and economic situations in the real world during the testing periods. Such results may have substantial implications for the policy how to choose the way of urbanization in a region.
基金Supported by Shannxi Leading Academic Discipline ProjectShannxi Science and Technology Project(the Key Industries R&D Programme)(2009K08-25)
文摘Using GIS, GPS, GPRS and RFID, a dynamic information management system of digital mining in an open pit was designed and developed.A linear programming model was set up in a practical application.By the model, the system can automatically draw up production plan of ore blending well every day.The system can monitor and dispatch open-pit trucks and shovels well, and can play back their historical paths.It can monitor and control the process of mining production in real time.By RFID, the system can also count the number of trucks'delivery and shovels'loading automatically.Experiments on real scenes show that the performance of this system is stable and can satisfy production standards of mining in open pits.
文摘Solid waste management aspect is one of the most important challenges facing the local administration in the Govemorate of Najaf. Therefore, this study aims to provide for solid waste management problem by choosing the best locations for the establishment of sanitary landfills in the governorate. In this study, GIS (geographic information system) and MCDA (multi-criteria decision analysis) were used based on 17 environmental, economic and geological criteria converted to input digital map layers. These were urban centres, cemetery, airports, electrical power lines, oil pipes, railways, roads, slope, historical sites, main rivers, industrial areas, religion sites, wells, military area, electrical power plants, nature reserves and national borders to select most importance sites in the govemorate. AHP (analytic hierarchy process) method was used in weighting the criteria used. All layers' maps were graded from 0 (not suitable) to 5 (most suitable) using spatial information scale then SAW (simple additive weighting) method was integrated in GIS used to calculate the suitability index for the studied area. The results indicated that 4.4% of the study region is suitable for landfill siting with grading values greater than 4.0. This included five sites distributed in three qadhaas of governorate.
基金supported by the Project of "Atlas of the People's Republic of China (New Century Edition)”funded by Ministry of Science and Technology, China (No. 2013FY112800)
文摘Suffering from fragile environment, poor accessibility and infrastructure, as well as social,political and economic marginality, the interprovincial mountain geographical entities are difficult areas for the regional governance in China.By analyzing the spatial patterns and the influencing factors of the interprovincial mountain geographical names(IMGNs), the goal of this research is to clarify the geographical features of IMGNs and offer alternatives for the management of interprovincial mountain regions in China. The spatial visualization,the analysis of spatial agglomeration and the influencing factors of IMGNs were all implemented under a geographical information system. Results showed that there were 6869 IMGNs in China according to the database of "China's Second National Survey of Geographical Names(2014-2018)",including 4209 mountain geographical names, 1684 mountain peak geographical names and 976 the other mountain geographical names. Hunan Province had the largest number of names while Shanghai had the smallest number of names. In addition, the spatial variance of the mountain peak names and the mountain names were larger than that of the other mountain geographical names, and the IMGNs showed a significant clustering phenomenon in the southern part of China. The relative elevation and the population had an impact on the distribution of the IMGNs. The largest number of the names occurred where the relative elevation was between 1000-2000 m and where the population was between 40-50 million. Density of unnamed interprovincial mountain geographical entities declined from west to east in China. The analysis of generic names of different types of IMGNs implied that the naming of IMGNs is inconsistent. Based on these analyses, it is suggested that the government should take the IMGNs as management units, strengthen the naming of unnamed interprovincial mountain geographical entities, standardize the generic names of IMGNs and identify areas of poverty based on the survey of IMGNs.