Conference Paper

Intermodal public transit routing using Linked Connections

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Abstract

Ever since public transit agencies have found their way to the Web, they inform travelers using route planning software made available on their website. These travelers also need to be informed about other modes of transport, for which they have to consult other websites, or for which they have to ask the transit agency's server maintainer to implement new functionalities. In this demo, we introduce an affordable publishing method for transit data, called Linked Connections, that can be used for intermodal route planning, by allowing user agents to execute the route planning algorithm. We publish paged documents containing a stream of hops between transit stops sorted by departure time. Using these documents, clients are able to perform intermodal route planning in a reasonable time. Furthermore, such clients are fully in charge of the algorithm, and can now also route in different ways by integrating datasets of a user’s choice. When visiting our demo, conference attendees will be able to calculate intermodal routes by querying the Web of data using their phone’s browser, without expensive server infrastructure.

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... The OpenStreetMap data for example can be used to build very specific route planning applications, such as a cycling route planning for the city of Brussels 1 or a route planner for motorcyclists that want scenic and curvy roads. 2 Public transit data is a noteworthy success story of Open Data, in large part due to the General Transit Feed Specification (GTFS): the preferred data format of the Google Transit APIs, which many people interact with through Google Maps. This is an example of a rising tide lifting all boats; most operators just want to get their data into the Google APIs, but the same data can be used by others for any use case. ...
... The Linked Connections specification [2] proposes a Linked Data alternative to GTFS data dumps, in which the public transit connections are published as a paginated collection, and each page contains data from a certain time interval. Applications that need only need data from a specific interval to answer a query can thus be more selective in the data they have to process. ...
... The Linked Connections specification [2] defines a way to publish transit data that falls somewhere in the middle of the Linked Data Fragments axis. Connections are defined as vehicles going from one stop to another without an intermediate halt. ...
Article
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... A connection is the actual departure time at a stop and an arrival at the next stop. These connections can be given a IRI, and described using RDF, using the Linked Connections [11] ontology. For this base algorithm and its derivatives, a connection object is the smallest building block of a transit schedule. ...
... This is serialized to a JSON format (https:/ / github.com/ linkedconnections/ benchmark-belgianrail#transit-schedules) that was introduced for benchmarking the Linked Connections route planner [11]. ...
... Choosing a use-case specific fragmentation strategy, can result in a cost-efficient data publishing interface while still being able to evaluate queries. The Linked Connections (LC) framework [2] enables third parties to develop route planning algorithms that evaluate queries over different data sources, taking into account multiple modes of transport (e.g., train, bus or tram). To achieve this, the server interface only exposes a paged collection of an ordered public transit connections list. ...
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Poster
Full-text available
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... In Figure 6we illustrate these two options as two extremes, with other options that are yet to be discovered. When a server only allows to set e.g., a departure station and a departure time, then the server cannot log the arrival station, yet the client is still able to plan a route by executing the algorithm on the client-side [8]. We would be able to fully rely on the query logs if the expressivity would be maximal (extreme right) and caching would be turned off. ...
Conference Paper
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... To cope with the shortcomings of SPARQL endpoints, the Semantic Web Community has created some technologies, such as Triple Pattern Fragments (TPFs), which divides the query processing between clients and servers and allows to restrict the kinds of queries the client can send to the server [13]. Linked Connections are an example of a customized query interface for the consumption of open data in the Transportation area [2]. Linked Connections implement HTTP content negotiation 7 [1]. ...
Conference Paper
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... The Linked Connections specification [9] defines a way to publish transit data that falls somewhere in the middle of the Linked Data Fragments axis. Connections are defined as vehicles going from one stop to another without an intermediate halt. ...
Conference Paper
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... For instance, the ORCA project aims at automatically assigning nurses to patient calls in a hospital based on their context [1]. Linked Connections define a way to publish raw transit data, to be used for intermodal route planning [3]. In projects like the aforementioned, it is common that the Semantic Web is not solely used as a means to publish data, but also as a catalyst to execute other actions, e.g., calling a real-world nurse, or executing a route planning algorithm. ...
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Chapter
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Round-based public transit routing
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The shortest path to happiness: Recommending beautiful, quiet, and happy routes in the city
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