All-in-One Lightweight GIS Platform

Miller Cylindrical Projection is a map projection method that projects the earth’s surface onto a two-dimensional plane. Its characteristic is that it emphasizes the left-right symmetry (mirror effect) of geographic information. This method is mainly used in scenes that value visual balance and overall grasp. It does not focus on the distance or shape from a specific center point, but focuses more on overall visibility and comparability.

QGZ files are compressed file formats used to save projects in QGIS (Quantum GIS) software. QGIS is an open source geographic information system (GIS) software that is widely used for visualization, editing, and analysis of spatial data. The QGZ format essentially compresses the configuration files (.qgs files in XML format) of the QGIS project into a single file for easy storage and transmission. Unlike QGS files, the QGZ format has better storage management capabilities and is particularly suitable for handling complex projects.

Raster data is a commonly used data format in geographic information systems (GIS). Its essence is a two-dimensional or three-dimensional data grid composed of a collection of pixels (grid cells). Each pixel (or cell) stores specific geographic information, such as terrain elevation, land use type, temperature or precipitation, expressed in the form of a numerical value. In the field of GIS, satellite images, aerial photos, digital elevation models (DEMs), etc. are usually stored and used in the form of raster data.

JGD2011 is a modern geocentric coordinate reference frame established by Japan in the early 21st century to replace the old Tokyo Datum (such as Tokyo 1918). Its core is based on the GRS80 ellipsoid, with the origin aligned with the center of mass of the earth, and the coordinate axis pointing in accordance with international standards (such as the prime meridian passing through Greenwich). This framework is implemented through space geodetic technologies such as GNSS and VLBI, with an accuracy of centimeters. It can dynamically reflect plate movement and earth deformation, and is suitable for high-precision geographic positioning needs in Japan and surrounding waters, and is gradually connected with international coordinate systems (such as ITRF).

E02 file is part of the ArcInfo export file (E00 format) developed by ESRI (Environmental Systems Research Institute) and is the second file to split the exported data. In the E00 format, large GIS data can be split into multiple files for storage. The first file is named E00, the second file is named E01, the third file is named E02, and so on. The E02 file itself does not contain complete GIS data and must be used in conjunction with the E00 and E01 files to form a complete data set. This format is used to circumvent file size limitations when transferring or storing data.

MGI coordinate system was established by the Austrian Military Geographical Institute. It is a local coordinate system based on the Bessel ellipsoid and is mainly used for geographic information representation and spatial positioning in Austria. It uses the Transverse Mercator projection, with the central meridian at 13°20′ east longitude, the latitude of the projection origin at 0°, the easting offset of 1,500,000 meters, and the northing offset of 0 meters. It is a variant of the Gauss-Krüger projection and is widely used in Austria in many fields such as topographic mapping, land management, urban planning, and transportation planning, providing an accurate spatial reference frame for these fields.

SDW files (Shapefile World File) are one of the subsidiary files of Shapefile files, which are used to store the projection and coordinate system information of Shapefile. Shapefile is a commonly used Geographic Information System (GIS) data format for storing geospatial data and attribute data. SDW files are usually used together with Shapefile’s SHP files and other related files such as DBF and PRJ files.

MPK (Map Package) is a file format used to organize and transmit map data. It is a file type developed by Esri (Environmental Systems Research Institute) to package maps, layers, and related resources in a geographic information system (GIS) into a single file. MPK files store map data in a compressed form and can contain map layers, symbol styles, label settings, data sources, and other information.

**DXF **(Drawing Exchange Format) is a CAD data exchange file format developed by Autodesk, mainly used in AutoCAD software. DXF saves graphic data in text format to facilitate data exchange between different CAD software. Its file extension is “.dxf”, which can store graphic information (lines, circles, polylines, etc.), layer information, coordinates, text, and annotations in CAD drawings.

Mercator Projection is one of the most famous map projections. It was first proposed by Franz Walter Mercator (Gerardus Mercator) in 1569 and is mainly used for drawing nautical charts. Mercator projection is a kind of orthogonal cylindrical projection, also known as “standard cylindrical projection”. Its characteristic is that it can project the longitude and latitude coordinates of the earth onto a plane, keeping the angle unchanged, so it is very useful in navigation and aviation.