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Planning of sustainable bridges using building information modeling
Published in Yusuf Arayici, John Counsell, Lamine Mahdjoubi, Gehan Nagy, Soheir Hawas, Khaled Dewidar, Heritage Building Information Modelling, 2017
Mohamed Marzouk, Mohamed Hisham
Figure 10.8 shows importing the bridge model to its location using Google SketchUp; Figure 10.9 shows the bridge model after being exported to Google Earth. In order to import GIS data to Google Earth, GIS shapefiles were used. Shapefiles are a common geospatial vector data format for geographic information systems software. Shapefiles were developed and regulated by ESRI. They spatially describe geometries such as points, polylines, and polygons. These, for example, could represent rivers and lakes. Each item may also have attributes that describe the item, such as the name or the length. The GIS data is imported to Google Earth as a shapefile (.shp). Figure 10.10 shows the visualization of the 3D bridge model with the imported GIS data. The Google Earth file that integrates the GIS data and 3D bridge model is saved in KMZ format, which is then linked to the BrIM model (IFC file) in Navisworks Manage software by performing a hyperlink that directly opens the Google Earth KMZ file.
GNSS Receivers
Published in Basudeb Bhatta, Global Navigation Satellite Systems, 2021
A free but very efficient Android-based app is SW Maps from Nepal (https://sw-maps-mobile-gis.soft112.com). It supports GPS, GLONASS, Galileo, BeiDou, and QZSS (in future it will also support IRNSS). One can record points, lines, polygons, and even photos by using this app; these recorded data can be displayed over a choice of background map/satellite image (e.g., Google Maps or OpenStreetMap) and attach custom attribute data to any feature. Attribute types include text, numbers, an option from a predefined set of choices, photos, audio clips, and videos. The app can even connect to external receivers (RTK-enabled receivers as well) via Bluetooth or USB. It supports import/export of several file formats such as KMZ, Shapefile, GeoJSON, GeoPackage, and many other formats. It can define and record multiple feature layers with different styling. One can even manually draw point/line/polygon features in this app. Once we create a project in this app, it can be exported as a template for other projects. This is useful when many surveyors and instruments are deployed to collect the same type of data. Templates can be created on a Windows PC using the SW Maps Template Builder tool, or exported from any existing project contained in a smartphone. It can process RTK data via internet. In spotty internet or no internet situations, it can log raw kinematic GNSS observations when using an external receiver. These raw observations can then be used for post-processing. An automatic tool has been developed for correcting recorded data points using CORS station in Kathmandu, Nepal. A tutorial of SW Maps can be downloaded from http://swmaps.softwel.com.np/assets/resources/manual.pdf.
Spatial Planning and Exergy – Design and Optimization
Published in Evanthia A. Nanaki, George Xydis, Exergetic Aspects of Renewable Energy Systems, 2019
Shapefiles are a widespread data format with geographic and geomorphological data designed to be used, studied and processed by all (most common) GIS programs. These files were initially developed as an open specification option for data interoperability between Esri and other GIS software products. The shapefile format can describe spatial vector features such as points, line and polygons, representing, for example, water wells, rivers, mountains and lakes. Each element typically has features that describe it, such as name or temperature.
Efficiently identifying closed roads by integrating and indexing open data
Published in Journal of the Chinese Institute of Engineers, 2021
Ya-Hui Chang, Shu-Han He, Chih-Wei Tseng
A road mileage map shows the correspondence between the road mileage and the longitude and latitude values. It is originally in the shapefile format, which is a geospatial vector data format especially designed for geographic information system software. We transform it into a human readable KML file, and some portion of a sample file is shown in Table 2.3 In a KML file, each Placemark element corresponds to a particular geographic location. It consists of several SimpleData sub-elements, each of which uses the value of the attribute ‘name’ to identify its function. Particularly, in L4, the value of the attribute ‘name’ is ‘road no’. It means that the element content ‘Tai 21’ is the number of this particular road. Similarly, in L3, the content ‘110 K + 000’ represents a certain road mileage, and the corresponding longitude and latitude values of this particular location are shown in L5-6, respectively. Note that ‘000 K + 000’ represents the start point of a road, and the correspondence between the mileage and the longitude/latitude values is sequentially recorded every 500 m in the road mileage map.
An open-source web service for creating quadrilateral grids based on the rHEALPix Discrete Global Grid System
Published in International Journal of Digital Earth, 2020
David Bowater, Emmanuel Stefanakis
Although the rHEALPix DGGS can be defined upon any reference ellipsoid (such as GRS80 or WGS84), this web service works strictly with WGS84 geodetic (longitude, latitude) coordinates. Output files from the grid generation operation are encoded in GeoJSON format (the 2016 GeoJSON Specification (RFC 7946) can be found at http://geojson.org/). We chose GeoJSON because it is a simple, text-based format that supports several geometric objects (such as Point, Linestring, and Polygon). In addition, GeoJSON files can easily be converted to other common file formats such as ESRI Shapefile, using free and open-source GIS software (e.g. QGIS). Using this format, we represent a grid as a ‘FeatureCollection’ where each grid cell is encoded as a ‘Feature’ that comprises its unique identifier and geometry. Figure 3 shows an example GeoJSON output file consisting of nine grid cells.
A Review of Spatial Big Data Platforms, Opportunities, and Challenges
Published in IETE Journal of Education, 2020
ArcGIS is a proprietary leading mapping and analytics platform with a rich set of functionalities provided by ESRI [10]. QGIS, on the other hand, is a free and open source geographic information system [11]. The GIS systems have evolved from Desktop GIS to Server GIS to Web GIS. The Desktop GIS system is a standalone application that can handle small-sized spatial data in shapefile file format. The shapefile format is an open standard that supports interoperability between different GIS applications. The focus of this system is geographic coordinate representation of spatial data and interactive visualization tools for map reading. In Server GIS, the file storage is replaced by a spatial database server at the back end. Server GIS is a multi-user system based on client server architecture, as shown in Figure 2, which can serve multiple spatial data applications. It can handle more data than monolithic Desktop GIS. The Web GIS is a Server GIS providing access to spatial data in a web portal using an online map server. The Google Map is an example of massive scale Web GIS.