A Sustainable Method for Publishing Interoperable Open Data on the Web

Raf Buyle,Julián Rojas Meléndez,Erik Mannens,Eveline Vlassenroot,Pieter Colpaert,Mathias Van Compernolle,Brecht Van De Vyvere,Stefan Lefever,Dwight Van Lancker,Peter Mechant

doi:10.3390/data6080093

Abstract

Smart cities need (sensor) data for better decision-making. However, while there are vast amounts of data available about and from cities, an intermediary is needed that connects and interprets (sensor) data on a Web-scale. Today, governments in Europe are struggling to publish open data in a sustainable, predictable and cost-effective way. Our research question considers what methods for publishing Linked Open Data time series, in particular air quality data, are suitable in a sustainable and cost-effective way. Furthermore, we demonstrate the cross-domain applicability of our data publishing approach through a different use case on railway infrastructure—Linked Open Data. Based on scenarios co-created with various governmental stakeholders, we researched methods to promote data interoperability, scalability and flexibility. The results show that applying a Linked Data Fragments-based approach on public endpoints for air quality and railway infrastructure data, lowers the cost of publishing and increases availability due to better Web caching strategies.

Highlights

At a load of four hundred clients that send a HyperText Transfer Protocol (HTTP) request every two seconds, we notice that the query response time of the Future Internet Ware (FIWARE) QL Application Programming Interface (API) increases to five seconds; at a higher load we obtain a timeout (Figure 10)
We presented insights on the implementation of a sustainable method for publishing open data, in a specific sensor data time series on air quality and railway infrastructure data
Our study demonstrates how Linked Data can support interoperability at the technical and semantical level for an air quality time series

Summary

Introduction

Most of the global population lives in urban areas, and it is expected that this will increase to nearly 70% by 2050 [1]. Such high levels of population growth create problems in waste management, air pollution and traffic mobility [1,2]. To avoid this accelerated urbanization turning into a crisis, cities must become “smart.” “Smart” refers to a continuous comprehensive commitment to innovation in technology, management and policy [3]. Air quality in Europe is regulated by Directive 2008/50/EC, which defines the threshold for the concentration of several pollutants

Results

Discussion

Conclusion