AINOKAISA TARNANEN’S MASTER’S THESIS “GIS-based modelling of cyclists’ speed and travel times in Helsinki region” was examined in September. In her thesis Ainokaisa developed a travel time model for calculating cyclists’ travel times in Helsinki region and examined the effect of different factors to cycling and the spatial differences in cycling speeds. Another objective was to assess how realistic it is to model cyclists’ travel times with constant speed on a regional scale. GPS data of cycling was collected from volunteers who had been tracking their cycling in Helsinki region with mobile sports applications. Road network for cycling and walking by Helsinki Region Transport was used as the modelling network.

The results show that slope, traffic lights and other junctions affect cycling speeds on an individual level but not on the regional scale. In general, the effect of signalized junctions is the greatest, whereas steep uphill slopes have the greatest effect on route-based mean speeds. The cycling speeds vary by cycling frequency: the more frequent cyclists have greater mean speeds. Spatial examination shows that mean cycling speeds in parts of central Helsinki are 0.8 times slower than in rest of the area.

A travel time model based on the constant speeds corresponding to the different median speeds of frequent and less frequent cyclists was implemented on the network. According to the results constant speed can be seen as an adequate assumption to model comparable cyclists’ travel times in Helsinki region. However, personal and spatial differences in cycling speeds should be taken into account. Travel times calculated with this model can be combined to the Helsinki region travel time matrix providing information on cycling alongside car, public transport and walking travel times and distances.

Thesis is available here:

You can find more information on Digital Geography Lab’s ongoing biking projects here: https://www.helsinki.fi/en/researchgroups/digital-geography-lab/biking-as-part-of-sustainable-urban-mobility-2017-2018

Novel data sources for accessibility modelling – Henrikki Tenkanen’s PhD course

November 2017 – Geography Master’s Programme

Course description

This course builds around Henrikki Tenkanen’s PhD-thesis titled “Dynamic Analysis of Accessibility and Mobility – Novel Approaches to Support Planning with Open Data and Tools“.

It will offer a possibility to be a part of the PhD defense process and to learn a lot about state of the art accessibility modelling and mobility analyses. The course consists of several meetings, course readings and discussions. In the kick-off meeting the course practicalities will be introduced. Minisymposium on accessibility brings together researchers and planners to discuss accessibility modelling using novel data sources. Shadow Defense works as a final rehearsal for Henrikki following the structure of the actual defense but with students being the opponents. The culmination of the course will be the actual defense with prof. Robert Weibel from the University of Zurich working as the opponent. Thoughts and ideas will be wrapped up in the last meeting of the course on the following week of the defense.

Schedule:

• 3.11. klo 10-12 (Physicum D112), Introduction to the course 
• 9.11. klo 12:30-16 (Physicum D101) Mini-symposium on Accessibility analyses using novel data sources

• • See the event page and register here

• 14.11. 12-16 (Physicum A115), Shadow defense with students making questions to Henrikki
• 17.11. 12-16 (Physicum D101), The PhD defense 
• 21.11. at 10-12 (Chemicum A128), Wrap up & discussion

Credits

This 2 credit point pop-up -course can be included to the course GEOG-328 Topical issues in geoinformatics (5 cr), or it can be one task in the GEOG-406GIS in Society course. Individual pieces (shadow defense, symposium, defense) can also be included in the GEOG_G338 Advanced Seminar of Geoinformatics. Please note, however, that participation can be counted only in one course!

Registration 

The registration to the course is done by enrolling to this Moodle area: https://moodle.helsinki.fi/course/view.php?id=26393#section-0

The registration key is “Henkasta_tohtori!”

Course completion

Participation to every course meeting is obligatory. Students will also need to read the provided course materials (Henrikki’s thesis, including a summary part and 5 scientific articles + 4-5 other scientific articles by the opponent and the presentators of the minisymposium).

Before the shadow defense students form journal groups. Each group chooses 2 articles from the thesis of which they discuss together and form questions that are presented to Henrikki in the shadow defense. The group reports their questions and findings how these questions were answered.

Evaluation

The course is evaluated on a scale pass-fail

Course Teachers

Henrikki Tenkanen, Tuuli Toivonen, Elias Willberg, and all participants!

Contacts  

tuuli.toivonen@helsinki.fi & elias.willberg@helsinki.fi

 

Ludovic, a Master student from the Civil Engineering French National School (ENTPE) and University of Lyon joined our Digital Geography Lab for five months as an intern to carry out his final year project in Helsinki.

Ludovic defended successfully his thesis titled “Cycling as a part of sustainable urban transport in Helsinki: Assessing the influence of weather on cycling activity” back in Lyon, France on 14^th September 2017. He’s research aimed at assessing how weather influences bicycle use, and thus empirically examined Helsinki as a case sample for a one year study period using both automatic bicycle counter system and bike sharing system (BSS) data sets, in addition to a detailed weather observation data from the Finnish Meteorological Institute. Ludovic showed i) how the influence of weather conditions depends on different time periods, ii) how different weather attributes influence cycling, and iii) to compare strengths and weaknesses of both cycling data sources in studying weather impact on cycling.

Results shows that weather conditions influence bicycle use more on weekends than during working days whereas weather influences cycling the least during peak hours (work-related cycling). The strongest influencing weather attribute is air temperature, yet also other attributes (e.g. wind, precipitation, humidity, snow) affect bicycle use. Statistical analyses showed similar weather influences on cycling for both data source regardless of differences between automatic counter and BSS data sources in case of counting locations (counting places vs BSS stations), bicycle users (own bikes vs part of public transport) and study period (all year vs summer period).

In conclusion, Ludovic’s work clearly indicates that weather conditions matter in using bicycles and is an excellent starting point for considering the influence of weather more in planning and developing urban cycling in Finland. Moreover, it revealed several promising research avenues and ways to develop methodology for obtaining more accurate assessments of weather influence on cycling.

Ludovic’s thesis is available here.

Welcome to a minisymposium on urban accessibility modelling on 9th November in Kumpula Campus. The symposium aims to bring together researchers and planners working with urban accessibility and mobility from Finland and abroad. 

The symposium is part of the Science workshops on novel and open data sources and approaches to study urban accessibility and mobility project funded by Finnish Cultural Foundation. It also links to the PhD defense of Henrikki Tenkanen, who defends his thesis  “Capturing time in space – Dynamic analyses of accessibility and mobility to support spatial planning with open data and tools” on 17th November.

See the program and register here!

Our work on cycling-related topics, accessibility-stuff and green areas & social media was presented at Geoinformatics research days and at Kaupunkisuunnittelumessut. 

Our interdisciplinary research group has established new webpages at helsinki.fi/digital-geography. This blog (blogs.helsinki.fi/accessibility) will continue to serve as a channel for distributing news about our mobility & accessibility research and the tools and data developed in the MetropAccess projects.

The Digital Geography Lab, based at the Faculty of Science, University of Helsinki, includes researchers working around the themes of mobility, accessibility, nature conservation and the development of novel data and methods for spatio-temporal analysis. Read more from helsinki.fi/digital-geography and @digigeolab Twitter account!

Enhancing spatial accuracy of mobile phone data using multi-temporal dasymetric interpolation paper by Olle Järv, Henrikki Tenkanen and Tuuli Toivonen has been published in the International Journal of Geographical Information Science. Check it out!

This is how Olle summarized the paper:

In brief, the paper highlights the need to give more attention to the uneven spatial resolution of mobile phone data which is one potential source of bias influencing research findings. To solve this, we are the first ones to apply an advanced dasymetric interpolation approach. Thus, we propose a generic multi-temporal function-based dasymetric interpolation method for mobile phone data, and demonstrate how it improves the spatial accuracy of mobile phone data as a proxy for people. The proposed method contributes also to the development of population modelling, at large.