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In order to adapt map tiles to high resolution display devices, some internet map providers pre-generate and store more than two sizes of map tiles. However, it is inefficient to download larger hi...

In order to explore the information management, the cloud computing technology is applied to the field of geographic information system, and remote sensing data storage and management system based on Hadoop is studied and realized. The main function of this system includes that the remote sensing data storage module provides the remote sensing data download function for data administrator, supports HTTP protocol and FTP protocol multi-threaded distributed HTTP download. The parallel constructing algorithm of remote sensing image of Pyramid based on Map Reduce is realized by the module, and layered cutting and block storage of massive remote sensing data are carried out. The GDAL open source library suitable for fast read raster data is used and it provides data resource for remote sensing data parallel cutting. In addition, the Geo Web Cache open source tile map service middleware is adopted and HBase is introduced as the storage support of tiles, which can deal with a large number of users’ visit, including loading and drag of maps. The system test is carried out to verify the effectiveness and practicability of the method proposed. The test results can show that the remote sensing data storage and management system based on Hadoop can effectively handle remote sensing data and improve the user’s experience. It is concluded that the information management system has high effectiveness and good practicability.

This paper describes the process of digitalization of old globes that brings with it the possibility to use globes in their digital form. Created digital models are available to the general public through modern technology in the Internet network. This gives an opportunity to study old globes located in various historical collections, and prevent damage of the originals. Another benefit of digitization is also a possibility of comparing different models both among themselves and with current map data by increasing the transparency of individual layers. Digitization is carried out using special device that allows digitizing globes with a diameter ranging from 5 cm to 120 cm. This device can be easily disassembled, and it is fully mobile therefore the globes can be digitized in the place of its storage. Image data of globe surface are acquired by digital camera firmly fastened to the device. Acquired image data are then georeferenced by using a method of complex adjustment. The last step of digitization is publication of the final models that is realized by two ways. The first option is in the form of 3D model through JavaScript library Cesium or Google Earth plug-in in the Web browser. The second option is as a georeferenced map using Tile Map Service.

Planning the use of marine areas requires support in allocating space to particular activities, assessing impacts and cumulative effects of activities, and generic decision making. The SmartSea project studies the Gulf of Bothnia, the northernmost arm of the Baltic Sea, as resource for sustainable growth. One objective of the project is to provide an open source and open access toolbox for marine spatial planning. Here we present a vision for the toolbox and an initial prototype. The vision is based on a model of information system as a meeting point of users, information providers, and tasks. A central technical requirement for the system was found to be a data model and related database of spatial planning and a programmable map service. An initial prototype of the system exists comprising a database, data browser/editor, dynamic tile map service, web mapping application, and extensions for a desktop GIS.

In order to upgrade the WebGIS legacy systems smoothly, and improve the response speed of traditional WebGIS and user experience, this paper designs and develops a tile map service based on middleware technology. Through systematic analysis of its basic principle and system architecture, this paper gives several optimization strategies. Finally, we make a performance comparison between tile map service middleware and traditional OGC (Open Geospatial Consortium, OGC) standard WMS service. Our experimental results show that the average response time of tile map service reduced by 46% than sending WMS request to WMS server directly, and the TMS middleware has a high efficiency when cutting map tiles dynamically because of its meta-tiling strategy. The study shows that tile map service middleware has important application value both in improving traditional WebGIS performance and in upgrading existing legacy systems.

Information technologies (ITs), and sports resources and services aid the potential to transform governmental organizations, and play an important role in contributing to sustainable communities development, respectively. Spatial data is a crucial source to support sports planning and management. Low-cost mobile geospatial tools bring productive and accurate data collection, and their use combining a handy and customized graphical user interface (GUI) (forms, mapping, media support) is still in an early stage. Recognizing the benefits — efficiency, effectiveness, proximity to citizens — that Mozambican Minister of Youth and Sports (MJD) can achieve with information resulted from the employment of a low-cost data collection platform, this project presents the development of a mobile mapping application (app) — m-SportGIS — under Open Source (OS) technologies and a customized evolutionary software methodology. The app development embraced the combination of mobile web technologies and Application Programming Interfaces (APIs) (e.g. Sencha Touch (ST), Apache Cordova, OpenLayers) to deploy a native-to-the-device (Android operating system) product, taking advantage of device’s capabilities (e.g. File system, Geolocation, Camera). In addition to an integrated Web Map Service (WMS), was created a local and customized Tile Map Service (TMS) to serve up cached data, regarding the IT infrastructures limitations in several Mozambican regions. m-SportGIS is currently being exploited by Mozambican Government staff to inventory all kind of sports facilities, which resulted and stored data feeds a WebGIS platform to manage Mozambican sports resources.

Within a digital map service environment, the rapid growth of Spatial Big-Data is driving new requirements for effective mechanisms for massive online vector map tile processing. The emergence of Not Only SQL (NoSQL) databases has resulted in a new data storage and management model for scalable spatial data deployments and fast tracking. They better suit the scenario of high-volume, low-latency network map services than traditional standalone high-performance computer (HPC) or relational databases. In this paper, we propose a flexible storage framework that provides feasible methods for tiled map data parallel clipping and retrieval operations within a distributed NoSQL database environment. We illustrate the parallel vector tile generation and querying algorithms with the MapReduce programming model. Three different processing approaches, including local caching, distributed file storage, and the NoSQL-based method, are compared by analyzing the concurrent load and calculation time. An online geological vector tile map service prototype was developed to embed our processing framework in the China Geological Survey Information Grid. Experimental results show that our NoSQL-based parallel tile management framework can support applications that process huge volumes of vector tile data and improve performance of the tiled map service.

WMS (Web Map Service) is the standard that is formulated by OGC (Open Geospatial Consortium), and TMS (Tile Map Service) is the specification that is formulated by OSGeo (Open Source Geospatial Foundation), the objective of both are to realize the sharing and interoperability of geographical information, using those standards, we can build the network that is composed of distributed map servers, the client can use them to request layers from the server, so we can release remote sensing image data into WMS or TMS in order to realize the sharing of remote sensing information. Through the comparative analysis, the speed of TMS requests and generates layers is greatly faster than WMS, which has an important meaning for improving the response speed of the traditional WebGIS server and ameliorating users' experience, therefore, this paper mainly studies the segmentation and release of remote sensing images that are based on Tile Map Service (TMS).

Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies. Since nowadays Web applications are increasingly providing plenty of creative and interesting services relying on new standards and more powerful computers, it becomes important to create similar applications, to process and visualize geographic data taking advantage of such groundings. In this context, it results interesting to develop new Web-based geo-processing based on a 3D data representation, exploiting the recent WebGL graphic specification from a client-side point of view. This research explains the novel way in which whole Valencian cadastre was analyzed, processed and finally represented into a WebGL-based virtual globe. These improvements provide end-users firstly, an optimization of computer graphics performance, by natively accessing to graphics instructions; and secondly a functional data management and representation for the present and forthcoming geo-processing Web-based platform.

This paper introduced a way to implement 3D WebGIS system which was based on WebGL technology. The system used Ellipsoidal Mercator projection and WGS84 coordinates, made JSON file format for network transformation, described popular method for tile map service, and finished a prototype system of 3D WebGIS. The prototype system was applied in a Remote Sensing Catalogue Service system. At last the paper discussed what's the good and bad aspects of WebGL.

Take open source GeoWebCache tile map service middleware as an example, through analysis of its basic principle and system architecture, this paper give three optimization strategies which are tile spatial index, extension mechanism and the deployment strategy. Finally, we make a performance comparison between GeoWebCache and traditional OGC (Open Geospatial Consortium, OGC) standard WMS(Web Map Service). Our experimental results show that the average response time of GeoWebCache reduced by 36% than sending WMS request to WMS server directly. The study shows that GeoWebCache middleware has important application value both in improving traditional WebGIS performance and in upgrading existing legacy systems.

With the development of remote sensing technology, remote sensing images have become an important source of spatial information. But the remote sensing images’ features of mass, multi-standard, multi-type, multi-scale and multi-thematic cause the difficulty in integrating different images to acquire needed information. This paper proposes an improved architecture of remote sensing image publishing system based on the advanced technologies of image pyramid, tile images, OGC specifications, TMS(Tile Map Service) and Flex. According to this improved system architecture, we design and implement a web-based thematic remote sensing image mutual response system that can publish multi-format, multi-source remote sensing images. Besides data sharing, it provides a comparison image service to users by achieving a linkage and mutual response among relevant images.

Information technologies and sport resources aid the potential to transform governmental organizations services, and play an important role in contributing to sustainable communities, respectively. Low-cost tools combining a user-friendly and customized data interaction (forms, mapping, media support) are still in an early stage. Recognizing benefits – efficiency, effectiveness, proximity to citizens – that Mozambican Minister of Youth and Sports (MJD) can achieve employing a low-cost data collection solution, this paper describes the development and implementation of a Geospatial Information System (GIS) mapping application (app) – m-SportGIS – under Open-Source (OS) technologies, customizing an evolutionary and incremental methodology. The app development embraced the combination of mobile web technologies and Application Programming Interfaces (APIs) (e.g. Sencha Touch (ST), Apache Cordova) to deploy a native-to-the-device (Samsung Galaxy Tab 2 running Android OS 4.0) app, taking advantage of device capabilities (e.g. File system, Geolocation, Camera). In addition to the integrated Web Map Service (WMS), a tile caching procedure was carried out to produce a network-communication-independent (offline) Tile Map Service (TMS) regarding IT infrastructures limitations in several Mozambican areas. m-SportGIS is currently being exploited by Mozambican Government staff to inventory all kind of sport facilities, which feeds a WebGIS platform to manage Mozambican sport resources.