Casablanca, Morocco's economic capital continues today to fight against the proliferation of informal settle- ments affecting its urban fabric illustrated especially by the slums. Actually Casablanca represents 25% of the total slums of Morocco [1]. These are the habitats of all deprived of healthy sanitary conditions and judged precarious from the perspective humanitarian and below the acceptable. The majority of the inhabi- tants of these slums are from the rural exodus with insufficient income to meet the basic needs of daily life. Faced with this situation and to eradicate these habitats, the Moroccan government has launched since 2004 an entire program to create cities without slums (C.W.S.) to resettle or relocate families. Indeed the process control and monitoring of this program requires first identifying and detecting spatial habitats. To achieve these tasks, conventional methods such as information gathering, mapping, use of databases and statistics often have shown their limits and are sometimes outdated. It is within this framework and that of the great German Morocco project “Urban agriculture as an integrative factor of development that fits our project de- tection of slums in Casablanca. The use of satellite imagery, particulary the HSR, has the advantage of providing the physical coverage of urban land but it raises the difficulty of choosing the appropriate method to apply.This paper is actually to develop new approaches based mainly on object-oriented classification of high spatial resolution satellite images for the detection of slums.This approach has been developed for mapping the urban land through by integration of several types of information (spectral, spatial, contextual ...) (Hofmann, P ., 2001, Herold et al. 2002b; Van Der Sande et al., 2003, Benz et al., 2004, Nobrega et al., 2006). In order to refine the result of classification, we applied mathematical morphology and in particular the closing filter. The data from this classification (binary image), which then will be used in a spatial data- base (ArcGIS).
摩洛哥的经济首都卡萨布兰卡今天继续与影响其城市结构的非正式住区扩散作斗争，特别是贫民窟。实际上，卡萨布兰卡的贫民窟占摩洛哥贫民窟总数的25%[1]。这些都是被剥夺了健康卫生条件的所有人的栖息地，从人道主义角度来看，它们被认为是不稳定的，是不可接受的。这些贫民窟的大多数居民来自农村，他们的收入不足以满足日常生活的基本需要。面对这种情况，为了消除这些栖息地，摩洛哥政府自2004年起启动了一项完整的计划，以创建无贫民窟的城市(C.W.S.)，重新安置或安置家庭。事实上，该计划的过程控制和监测首先需要识别和检测空间栖息地。为了完成这些任务，诸如信息收集、制图、使用数据库和统计等传统方法往往显示出其局限性，有时已经过时。正是在这个框架和伟大的德国摩洛哥项目“城市农业作为发展的综合因素”的框架内，适合我们对卡萨布兰卡贫民窟的项目检测。使用卫星图像，特别是高铁，具有提供城市土地物理覆盖的优势，但它增加了选择适当方法的困难。本文实际上是基于面向对象的高空间分辨率卫星图像分类开发新的贫民窟检测方法。这种方法是通过整合几种类型的信息(光谱、空间、背景……)来绘制城市土地地图的(Hofmann, P .， 2001, Herold et al. 2002b;Van Der Sande等人，2003,Benz等人，2004,Nobrega等人，2006)。为了改进分类结果，我们应用了数学形态学，特别是闭合滤波器。这种分类的数据(二值图像)，然后将在空间数据库(ArcGIS)中使用。
{"title":"Detecting Slums from SPOT Data in Casablanca Morocco Using an Object Based Approach","authors":"H. Rhinane, A. Hilali, A. Berrada, M. Hakdaoui","doi":"10.4236/jgis.2011.33018","DOIUrl":"https://doi.org/10.4236/jgis.2011.33018","url":null,"abstract":"Casablanca, Morocco's economic capital continues today to fight against the proliferation of informal settle- ments affecting its urban fabric illustrated especially by the slums. Actually Casablanca represents 25% of the total slums of Morocco [1]. These are the habitats of all deprived of healthy sanitary conditions and judged precarious from the perspective humanitarian and below the acceptable. The majority of the inhabi- tants of these slums are from the rural exodus with insufficient income to meet the basic needs of daily life. Faced with this situation and to eradicate these habitats, the Moroccan government has launched since 2004 an entire program to create cities without slums (C.W.S.) to resettle or relocate families. Indeed the process control and monitoring of this program requires first identifying and detecting spatial habitats. To achieve these tasks, conventional methods such as information gathering, mapping, use of databases and statistics often have shown their limits and are sometimes outdated. It is within this framework and that of the great German Morocco project “Urban agriculture as an integrative factor of development that fits our project de- tection of slums in Casablanca. The use of satellite imagery, particulary the HSR, has the advantage of providing the physical coverage of urban land but it raises the difficulty of choosing the appropriate method to apply.This paper is actually to develop new approaches based mainly on object-oriented classification of high spatial resolution satellite images for the detection of slums.This approach has been developed for mapping the urban land through by integration of several types of information (spectral, spatial, contextual ...) (Hofmann, P ., 2001, Herold et al. 2002b; Van Der Sande et al., 2003, Benz et al., 2004, Nobrega et al., 2006). In order to refine the result of classification, we applied mathematical morphology and in particular the closing filter. The data from this classification (binary image), which then will be used in a spatial data- base (ArcGIS).","PeriodicalId":93313,"journal":{"name":"Journal of geographic information system","volume":"4 1","pages":"217-224"},"PeriodicalIF":0.0,"publicationDate":"2011-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86093955","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Urbanization changes have been widely examined and numerous urban growth models have been proposed. We introduce an alternative urban growth model specifically designed to incorporate spatial heterogeneity in urban growth models. Instead of applying a single method to the entire study area, we segment the study area into different regions and apply targeted algorithms in each subregion. The working hypothesis is that the integration of appropriately selected region-specific models will outperform a globally applied model as it will incorporate further spatial heterogeneity. We examine urban land use changes in Denver, Colorado. Two land use maps from different time snapshots (1977 and 1997) are used to detect the urban land use changes, and 23 explanatory factors are produced to model urbanization. The proposed Spatially Heterogeneous Expert Based (SHEB) model tested decision trees as the underlying modeling algorithm, applying them in different subregions. In this paper the segmentation tested is the division of the entire area into interior and exterior urban areas. Interior urban areas are those situated within dense urbanized structures, while exterior urban areas are outside of these structures. Obtained results on this model regionalization technique indicate that targeted local models produce improved results in terms of Kappa, accuracy percentage and multi-scale performance. The model superiority is also confirmed by model pairwise comparisons using t-tests. The segmentation criterion of interior/exterior selection may not only capture specific characteristics on spatial and morphological properties, but also socioeconomic factors which may implicitly be present in these spatial representations. The usage of interior and exterior subregions in the present study acts as a proof of concept. Other spatial heterogeneity indicators, for example landscape, socioeconomic and political boundaries could act as the basis for improved local segmentations.
{"title":"A Spatially Heterogeneous Expert Based (SHEB) Urban Growth Model using Model Regionalization","authors":"D. Triantakonstantis, G. Mountrakis, Jida Wang","doi":"10.4236/jgis.2011.33016","DOIUrl":"https://doi.org/10.4236/jgis.2011.33016","url":null,"abstract":"Urbanization changes have been widely examined and numerous urban growth models have been proposed. We introduce an alternative urban growth model specifically designed to incorporate spatial heterogeneity in urban growth models. Instead of applying a single method to the entire study area, we segment the study area into different regions and apply targeted algorithms in each subregion. The working hypothesis is that the integration of appropriately selected region-specific models will outperform a globally applied model as it will incorporate further spatial heterogeneity. We examine urban land use changes in Denver, Colorado. Two land use maps from different time snapshots (1977 and 1997) are used to detect the urban land use changes, and 23 explanatory factors are produced to model urbanization. The proposed Spatially Heterogeneous Expert Based (SHEB) model tested decision trees as the underlying modeling algorithm, applying them in different subregions. In this paper the segmentation tested is the division of the entire area into interior and exterior urban areas. Interior urban areas are those situated within dense urbanized structures, while exterior urban areas are outside of these structures. Obtained results on this model regionalization technique indicate that targeted local models produce improved results in terms of Kappa, accuracy percentage and multi-scale performance. The model superiority is also confirmed by model pairwise comparisons using t-tests. The segmentation criterion of interior/exterior selection may not only capture specific characteristics on spatial and morphological properties, but also socioeconomic factors which may implicitly be present in these spatial representations. The usage of interior and exterior subregions in the present study acts as a proof of concept. Other spatial heterogeneity indicators, for example landscape, socioeconomic and political boundaries could act as the basis for improved local segmentations.","PeriodicalId":93313,"journal":{"name":"Journal of geographic information system","volume":"40 1","pages":"195-210"},"PeriodicalIF":0.0,"publicationDate":"2011-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90754102","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Layered information systems like Google Earth have revolutionized public access to and visualization of geographic information through virtual globes. Separately, geo-specific technical information has been advanced in mobile platforms, both handheld and embedded devices, for the engineering and scientific communities. However, engineering and scientific information has had limited penetration into virtual globe Geographic Information Systems (GIS). This article explores unmet expectations which may be at the root of the issue. These expectations include design of the architecture within the originating mobile platform as well as expression of the level of accuracy and precision necessary for validity of the simulation displayed through the virtual globe GIS. The article below discusses architecture and validity research that advances real-time generation of simulated electro-magnetic coverage maps as composed layers within a mobile platform. Further, the research also enables real-time visualization of the simulated coverage maps by a global team through a virtual globe. Finally, for communication assurance purposes, the level of validity of the generated simulated coverage maps are analyzed from the perspective of an analog celestial body exploration mission by a mobile rover and its supporting organization analysis needs.
{"title":"Expectations for Presentation of Engineering and Scientific Mobile Platform Information within a Virtual Globe Geographic Information Systems","authors":"Brian Guise, M. Proctor","doi":"10.4236/jgis.2011.32008","DOIUrl":"https://doi.org/10.4236/jgis.2011.32008","url":null,"abstract":"Layered information systems like Google Earth have revolutionized public access to and visualization of geographic information through virtual globes. Separately, geo-specific technical information has been advanced in mobile platforms, both handheld and embedded devices, for the engineering and scientific communities. However, engineering and scientific information has had limited penetration into virtual globe Geographic Information Systems (GIS). This article explores unmet expectations which may be at the root of the issue. These expectations include design of the architecture within the originating mobile platform as well as expression of the level of accuracy and precision necessary for validity of the simulation displayed through the virtual globe GIS. The article below discusses architecture and validity research that advances real-time generation of simulated electro-magnetic coverage maps as composed layers within a mobile platform. Further, the research also enables real-time visualization of the simulated coverage maps by a global team through a virtual globe. Finally, for communication assurance purposes, the level of validity of the generated simulated coverage maps are analyzed from the perspective of an analog celestial body exploration mission by a mobile rover and its supporting organization analysis needs.","PeriodicalId":93313,"journal":{"name":"Journal of geographic information system","volume":"7 1","pages":"120-127"},"PeriodicalIF":0.0,"publicationDate":"2011-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80122574","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The changing trends in information technology have greatly influenced the role of GIS in spatial data management, analysis, processing and presentation. It has evolved from the conventional cartography and image processing to advanced 3D visualization and dynamic graphics tools. Due to this evolving nature of GIS, it has found wide applications in a number of diverse fields. Geophysical exploration projects involve data acquisition at hundreds of spatial locations resulting in large number of datasets. It takes a great deal of time to manage all these datasets during data processing and interpretation. This paper presents the use of GIS as an effective project management tool, providing an interactive data access interface in compute intensive geophysical processing applications. A reusable GIS software component is presented which can be used by geophysical applications to manage their datasets. A practical example is included to demonstrate the implementation of this GIS component as an embedded Project Manager in a seismic refraction software.
{"title":"GIS as Project Manager in Geophysical Applications Software","authors":"K. A. Khan, G. Akhter, Z. Ahmad","doi":"10.4236/jgis.2011.32014","DOIUrl":"https://doi.org/10.4236/jgis.2011.32014","url":null,"abstract":"The changing trends in information technology have greatly influenced the role of GIS in spatial data management, analysis, processing and presentation. It has evolved from the conventional cartography and image processing to advanced 3D visualization and dynamic graphics tools. Due to this evolving nature of GIS, it has found wide applications in a number of diverse fields. Geophysical exploration projects involve data acquisition at hundreds of spatial locations resulting in large number of datasets. It takes a great deal of time to manage all these datasets during data processing and interpretation. This paper presents the use of GIS as an effective project management tool, providing an interactive data access interface in compute intensive geophysical processing applications. A reusable GIS software component is presented which can be used by geophysical applications to manage their datasets. A practical example is included to demonstrate the implementation of this GIS component as an embedded Project Manager in a seismic refraction software.","PeriodicalId":93313,"journal":{"name":"Journal of geographic information system","volume":"6 1","pages":"166-172"},"PeriodicalIF":0.0,"publicationDate":"2011-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83157270","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In recent years, several results have been introduced to enhance distributed GIS performance. While much more efforts have focused on tile map and simple symbologies on dynamic map, load balancing GIS servers have not been addressed by the GIS community so far. This paper, therefore, proposed dynamic distributed load balancing for D-GIS in order to quickly render information to client interface by involving a set of GIS servers which process clients’ requests depending of an algorithm. In the model, several concepts were introduced and defined: Virtual Server within physical machine which constitutes a setup environment for a single GIS server, Load Hash Table which contains information about virtual server’s capacity, real-time load and other mandatory elements, Request Split Table which splits requests depending of the input area’s Quantity of Information and stores request tasks composition for later reconstitution. At last we have Distributed Failover Callback Function Table level one (respectively level two) which determines whether or not the request had been successfully processed by the chosen virtual server (respectively physical machine). This table allows sending back the same request to another virtual server (respectively physical node). Two load handlers (primary and secondary) are defined in case of failure. Our Model achieves efficient load balancing by: providing efficient node selection; optimizing request routing; managing node failover; involving client’s request partitioning and introducing method type decomposition. A simulation of the algorithm shows a low response time when performing GIS operations.
{"title":"Dynamic-Distributed Load Balancing for Highly-Performance and Responsiveness Distributed-GIS (D-GIS)","authors":"Aissatou Diasse, F. Kone","doi":"10.4236/jgis.2011.32009","DOIUrl":"https://doi.org/10.4236/jgis.2011.32009","url":null,"abstract":"In recent years, several results have been introduced to enhance distributed GIS performance. While much more efforts have focused on tile map and simple symbologies on dynamic map, load balancing GIS servers have not been addressed by the GIS community so far. This paper, therefore, proposed dynamic distributed load balancing for D-GIS in order to quickly render information to client interface by involving a set of GIS servers which process clients’ requests depending of an algorithm. In the model, several concepts were introduced and defined: Virtual Server within physical machine which constitutes a setup environment for a single GIS server, Load Hash Table which contains information about virtual server’s capacity, real-time load and other mandatory elements, Request Split Table which splits requests depending of the input area’s Quantity of Information and stores request tasks composition for later reconstitution. At last we have Distributed Failover Callback Function Table level one (respectively level two) which determines whether or not the request had been successfully processed by the chosen virtual server (respectively physical machine). This table allows sending back the same request to another virtual server (respectively physical node). Two load handlers (primary and secondary) are defined in case of failure. Our Model achieves efficient load balancing by: providing efficient node selection; optimizing request routing; managing node failover; involving client’s request partitioning and introducing method type decomposition. A simulation of the algorithm shows a low response time when performing GIS operations.","PeriodicalId":93313,"journal":{"name":"Journal of geographic information system","volume":"33 4 1","pages":"128-139"},"PeriodicalIF":0.0,"publicationDate":"2011-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87665497","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hongxing Liu, Lei Wang, D. Sherman, Qiusheng Wu, Haibin Su
This paper presents algorithmic components and corresponding software routines for extracting shoreline features from remote sensing imagery and LiDAR data. Conceptually, shoreline features are treated as boundary lines between land objects and water objects. Numerical algorithms have been identified and de-vised to segment and classify remote sensing imagery and LiDAR data into land and water pixels, to form and enhance land and water objects, and to trace and vectorize the boundaries between land and water ob-jects as shoreline features. A contouring routine is developed as an alternative method for extracting shore-line features from LiDAR data. While most of numerical algorithms are implemented using C++ program-ming language, some algorithms use available functions of ArcObjects in ArcGIS. Based on VB .NET and ArcObjects programming, a graphical user’s interface has been developed to integrate and organize shoreline extraction routines into a software package. This product represents the first comprehensive software tool dedicated for extracting shorelines from remotely sensed data. Radarsat SAR image, QuickBird multispectral image, and airborne LiDAR data have been used to demonstrate how these software routines can be utilized and combined to extract shoreline features from different types of input data sources: panchromatic or single band imagery, color or multi-spectral image, and LiDAR elevation data. Our software package is freely available for the public through the internet.
{"title":"Algorithmic Foundation and Software Tools for Extracting Shoreline Features from Remote Sensing Imagery and LiDAR Data","authors":"Hongxing Liu, Lei Wang, D. Sherman, Qiusheng Wu, Haibin Su","doi":"10.4236/JGIS.2011.32007","DOIUrl":"https://doi.org/10.4236/JGIS.2011.32007","url":null,"abstract":"This paper presents algorithmic components and corresponding software routines for extracting shoreline features from remote sensing imagery and LiDAR data. Conceptually, shoreline features are treated as boundary lines between land objects and water objects. Numerical algorithms have been identified and de-vised to segment and classify remote sensing imagery and LiDAR data into land and water pixels, to form and enhance land and water objects, and to trace and vectorize the boundaries between land and water ob-jects as shoreline features. A contouring routine is developed as an alternative method for extracting shore-line features from LiDAR data. While most of numerical algorithms are implemented using C++ program-ming language, some algorithms use available functions of ArcObjects in ArcGIS. Based on VB .NET and ArcObjects programming, a graphical user’s interface has been developed to integrate and organize shoreline extraction routines into a software package. This product represents the first comprehensive software tool dedicated for extracting shorelines from remotely sensed data. Radarsat SAR image, QuickBird multispectral image, and airborne LiDAR data have been used to demonstrate how these software routines can be utilized and combined to extract shoreline features from different types of input data sources: panchromatic or single band imagery, color or multi-spectral image, and LiDAR elevation data. Our software package is freely available for the public through the internet.","PeriodicalId":93313,"journal":{"name":"Journal of geographic information system","volume":"18 1","pages":"99-119"},"PeriodicalIF":0.0,"publicationDate":"2011-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73081626","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Urban fringes represent very complex landscapes because of their proximity and mutual dependency with cities and rural areas. These landscapes may be considered as transition entities characterized by fuzzy boundaries. An uncontrolled development of urban sprawl and land use changes in these areas may determine negative impacts on all natural, economic and social components. Thus, urban fringes assume a key-role in modern landscape analysis, planning and management. Landscape analysis of these interfaces, as this study shows, can be effectively supported by GIS spatial modelling. The Settlement Density Index (SDI), developed through GIS spatial analysis techniques, expresses punctually the territorial gradients generated by the presence of settlements and allows the identification of the urban fringes in the two periods under investigation. These areas are then characterized and analyzed quantitatively using detailed land use data. The comparison of the diachronic information highlights the transformations of peri-urban landscapes that appear mainly related to the modifications of spatial configuration of urban areas and to the changes of agricultural systems.
{"title":"Peri-Urban Transformations in Agricultural Landscapes of Perugia, Italy","authors":"Marco Vizzari","doi":"10.4236/jgis.2011.32011","DOIUrl":"https://doi.org/10.4236/jgis.2011.32011","url":null,"abstract":"Urban fringes represent very complex landscapes because of their proximity and mutual dependency with cities and rural areas. These landscapes may be considered as transition entities characterized by fuzzy boundaries. An uncontrolled development of urban sprawl and land use changes in these areas may determine negative impacts on all natural, economic and social components. Thus, urban fringes assume a key-role in modern landscape analysis, planning and management. Landscape analysis of these interfaces, as this study shows, can be effectively supported by GIS spatial modelling. The Settlement Density Index (SDI), developed through GIS spatial analysis techniques, expresses punctually the territorial gradients generated by the presence of settlements and allows the identification of the urban fringes in the two periods under investigation. These areas are then characterized and analyzed quantitatively using detailed land use data. The comparison of the diachronic information highlights the transformations of peri-urban landscapes that appear mainly related to the modifications of spatial configuration of urban areas and to the changes of agricultural systems.","PeriodicalId":93313,"journal":{"name":"Journal of geographic information system","volume":"50 1","pages":"145-152"},"PeriodicalIF":0.0,"publicationDate":"2011-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88448320","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
K. Iwao, K. Nasahara, T. Kinoshita, Y. Yamagata, Dave Patton, S. Tsuchida
We present here a new approach to the development of a global land cover map. We combined three existing global land cover maps (MOD12, GLC2000, and UMD) based on the principle that the majority view prevails and validated the resulting map by using information collected as part of the Degree Confluence Project (DCP). We used field survey information gathered by DCP volunteers from 4211 worldwide locations to validate the new land cover map, as well as the three existing land cover maps that were combined to create it. Agreement between the DCP-derived information and the land cover maps was 61.3% for our new land cover map, 60.3% for MOD12, 58.9% for GLC2000, and 55.2% for UMD. Although some of the improvements we achieved were not statistically significant, this project has shown that an improved land cover map can be developed and well-validated globally using our method.
{"title":"Creation of New Global Land Cover Map with Map Integration","authors":"K. Iwao, K. Nasahara, T. Kinoshita, Y. Yamagata, Dave Patton, S. Tsuchida","doi":"10.4236/jgis.2011.32013","DOIUrl":"https://doi.org/10.4236/jgis.2011.32013","url":null,"abstract":"We present here a new approach to the development of a global land cover map. We combined three existing global land cover maps (MOD12, GLC2000, and UMD) based on the principle that the majority view prevails and validated the resulting map by using information collected as part of the Degree Confluence Project (DCP). We used field survey information gathered by DCP volunteers from 4211 worldwide locations to validate the new land cover map, as well as the three existing land cover maps that were combined to create it. Agreement between the DCP-derived information and the land cover maps was 61.3% for our new land cover map, 60.3% for MOD12, 58.9% for GLC2000, and 55.2% for UMD. Although some of the improvements we achieved were not statistically significant, this project has shown that an improved land cover map can be developed and well-validated globally using our method.","PeriodicalId":93313,"journal":{"name":"Journal of geographic information system","volume":"112 1","pages":"160-165"},"PeriodicalIF":0.0,"publicationDate":"2011-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76537538","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jazmín Ponce-Rojas, S. Vidal-Beltrán, M. A. Acevedo-Mosqueda, Montserrat Jiménez-Licea
This paper shows the procedure to obtain a continuous coverage map based on a collection of power meas- urements using a Geographic Information System, through satellite photographs of the Professional Unit Adolfo Lopez Mateos, and a group of punctual samples of the power of the Common Pilot Channel (CPICH); which is used to estimate the radio communications channel conditions, taken at different positions and dis- tances. These samples were taken using specialized equipment to obtain georeferenced measurements, and by a technique of statistical prediction, as the Krige Method, generate continuous coverage maps, making it possible to know the distribution of power, and therefore understanding the behavior and configuration of a Base Station, which in third generation cellular systems is also called Node B.
{"title":"A Geographic Information System Applied to Coverage Maps of 3G Cellular Communications Networks","authors":"Jazmín Ponce-Rojas, S. Vidal-Beltrán, M. A. Acevedo-Mosqueda, Montserrat Jiménez-Licea","doi":"10.4236/jgis.2011.32010","DOIUrl":"https://doi.org/10.4236/jgis.2011.32010","url":null,"abstract":"This paper shows the procedure to obtain a continuous coverage map based on a collection of power meas- urements using a Geographic Information System, through satellite photographs of the Professional Unit Adolfo Lopez Mateos, and a group of punctual samples of the power of the Common Pilot Channel (CPICH); which is used to estimate the radio communications channel conditions, taken at different positions and dis- tances. These samples were taken using specialized equipment to obtain georeferenced measurements, and by a technique of statistical prediction, as the Krige Method, generate continuous coverage maps, making it possible to know the distribution of power, and therefore understanding the behavior and configuration of a Base Station, which in third generation cellular systems is also called Node B.","PeriodicalId":93313,"journal":{"name":"Journal of geographic information system","volume":"120 1","pages":"140-144"},"PeriodicalIF":0.0,"publicationDate":"2011-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79427766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Unit hydrographs (UH) are either determined from gauged data or derived using empirically-based synthetic unit hydrograph procedures. In Saudi Arabia, the discharge records may not be available either for several locations or for long time scales, and therefore synthetic unit hydrographs are crucial in flood and water resources management. Available metrological, geological, and land use datasets have been utilized in order to apply the US National Resources Conservative Services (NRCS) methodology in a Geographic Information Systems (GIS) environment. Furthermore, NRCS unit hydrographs have been developed for six watersheds within Makkah metropolitan area, southwest Saudi Arabia. The accomplished results show that the UH time to peak discharge vary from 1.15 hours to 4.47 hours, and the UH peak discharge quantities range from 10.14 m 3 /s to 16.74 m 3 /s. It is concluded that the third basin in Makkah city may be considered as the most hazardous catchment. Hence, it is recommended that careful flood protection procedures should be taken in this area within Makkah city.
单位海道线(UH)要么是根据测量数据确定的，要么是使用基于经验的合成单位海道线程序得出的。在沙特阿拉伯，可能无法获得几个地点或长时间尺度的流量记录，因此合成单位水文在洪水和水资源管理中至关重要。为了在地理信息系统(GIS)环境中应用美国国家资源保护局(NRCS)的方法，利用了现有的计量、地质和土地利用数据集。此外，还为沙特阿拉伯西南部的麦加大都市区内的六个流域开发了NRCS单位水线。研究结果表明:UH的峰值放电时间为1.15 ~ 4.47 h，峰值放电量为10.14 ~ 16.74 m 3 /s。结论认为，位于麦加市的第三流域可能是最危险的流域。因此，建议在麦加市内的这一地区采取谨慎的防洪措施。
{"title":"Developing GIS-Based Unit Hydrographs for Flood Management in Makkah Metropolitan Area, Saudi Arabia","authors":"G. Dawod, N. Koshak","doi":"10.4236/jgis.2011.32012","DOIUrl":"https://doi.org/10.4236/jgis.2011.32012","url":null,"abstract":"Unit hydrographs (UH) are either determined from gauged data or derived using empirically-based synthetic unit hydrograph procedures. In Saudi Arabia, the discharge records may not be available either for several locations or for long time scales, and therefore synthetic unit hydrographs are crucial in flood and water resources management. Available metrological, geological, and land use datasets have been utilized in order to apply the US National Resources Conservative Services (NRCS) methodology in a Geographic Information Systems (GIS) environment. Furthermore, NRCS unit hydrographs have been developed for six watersheds within Makkah metropolitan area, southwest Saudi Arabia. The accomplished results show that the UH time to peak discharge vary from 1.15 hours to 4.47 hours, and the UH peak discharge quantities range from 10.14 m 3 /s to 16.74 m 3 /s. It is concluded that the third basin in Makkah city may be considered as the most hazardous catchment. Hence, it is recommended that careful flood protection procedures should be taken in this area within Makkah city.","PeriodicalId":93313,"journal":{"name":"Journal of geographic information system","volume":"30 1","pages":"160-165"},"PeriodicalIF":0.0,"publicationDate":"2011-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73190856","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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