A WebGIS for Visualizing Historical Activities Based on Photos: The Project of Yunnan–Vietnam Railway Web Map

Abstract

Historical photos have significance for historical and social studies. Especially, the introduction of Geographic Information System (GIS) and digitalized historical photos have brought more opportunities and possibilities for interdisciplinary studies and the convenience for normal citizens to participate in the landscape observation. To this aim, this paper first reviews the research related to historical photos and Open GIS, and points out the meaning of historical photos for the Yunnan–Vietnam Railway (YVR). Based on the collected data of original historical photos from archives and the fieldwork data that recorded the landscape along the railway from 2018 to 2019, a WebGIS of Yunnan–Vietnam Railway is designed and implemented with open GIS tools. All the data are processed in the QGIS as vector and raster layers and loaded in PostgreSQL as relational tables. Then, heatmaps are created indicating the density of historical activities of the railway company, the other historical photographers, and current touristic activities. Connected with the PostgreSQL database, the data are uploaded to GeoServer for more GIS functionalities. Finally, the whole system lives in a webpage, implemented in HTML and JavaScript with Leaflet, and the improved functionalities of the Yunnan–Vietnam Railway WebGIS include distance measuring, search engine, and historical information browsing. In the future, further research can be done focusing on the landscape changes along the railway and public participation during the landscape observation.

The Brazilian Soil Spectral Service (BraSpecS): A User-Friendly System for Global Soil Spectra Communication

“…In the data locations module, the user visualizes the number of samples by Brazilian states and identifies the authors and partner institutions. The map interaction of the Brazilian states was elaborated using the Leaflet library [42]. The soil data visualization module shows soil spectra in the vis-NIR-SWIR, and MIR bands filtered by classifications, orders, groups, layers, and textures.…”

3D WebGIS for Ephemeral Architecture Documentation and Studies in the Humanities

“…Due to their nature, relational DBs allow the relation between entities, representing the most logical solution for projects dealing with cataloging and archiving [35], common activities performed when dealing with CH. Data can be stored in spatial DBs to handle geometries and their coordinates in a defined reference system [28]. Data can be queried using structured query language (SQL), and predefined queries can be integrated into the application, enabling users to apply them just by clicking a button and without knowing SQL [32].…”

“…Past events can be retraced and narrated in WebGIS applications, and the visualization of ephemeral architecture can be achieved by reconstructing structures, thanks to historical depictions and maps, as in the case of Napoleon's journey to Venice [27]. A WebGIS is used not only for data archiving, visualization, queries, and downloads but also for generating analysis maps-such as density maps and statistical data-allowing the retrieval of, for instance, the distribution of historical images for the Yunnan-Vietnam Railway [28]. Relationships between historical events, their locations, and people can be observed over time, such as the influence played by an important Chinese politician across China [29] or the Australian places visited by the explorer Sir Joh Forrest over the 19th century [30].…”

“…In general, people experience places from the human point of view and in a 3D visualization, and not using 2D representations from a bird's-eye view. In almost all the studies here considered, a WebGIS is solely conceived as 2D, missing an opportunity to make historical places more understandable to everyone [21,28,29]. Ontologies and cataloging standards for historical documents and architectures are rarely adopted and declared; good examples are the study conducted by Wei [29] for ontologies' applications in relating people, events, places, and time-and the Istituto Superiore per la Protezione e la Ricerca Ambientale (ISPRA) geoportal-regarding the application of cataloging standards to maps.…”

“…Ontologies and cataloging standards for historical documents and architectures are rarely adopted and declared; good examples are the study conducted by Wei [29] for ontologies' applications in relating people, events, places, and time-and the Istituto Superiore per la Protezione e la Ricerca Ambientale (ISPRA) geoportal-regarding the application of cataloging standards to maps. Relationships are not always considered, missing an opportunity to expand knowledge; a good example is provided by [28]. Often, a WebGIS is employed to publish research results, but the link is not provided or is no longer available-like in the MayaArch3D project [32] 1 -overlooking the opportunity provided by a WebGIS to exchange data and stressing the need for maintenance or archival plans for WebGIS applications.…”