A Voice Service Development Kit for the Kasadaka platform

[This post is written by André Baart and describes his MSc thesis]

While the internet usage in the developing world is still low, the adoption of simple mobile phones is widespread. A way to offer the advantages of the internet to these populations is voice-based information systems. The KasaDaka voice-services platform is aimed at providing voice-services in the context of ICT for Development (ICT4D). The platform is based on a Raspberry Pi and a GSM modem, which enables affordable voice-service hosting, using the locally available GSM network. The platform takes into account the special requirements of the ICT4D context, such as limited internet connectivity and low literacy rates.

This research focuses on lowering the barrier to entry of voice-service development, by reducing the skill set needed to do so. A Voice Service Development Kit (VSDK) is developed that allows the development of voice-services by deploying and customizing provided building-blocks. These building blocks each represent a type of interaction that is often found in voice-services. (for example a menu, user voice input or the playback of a message) The researcher argues that the simplification of voice-service development is an essential step towards sustainable voice-services in the ICT4D context; As this increases the potential number of local voice-service developers, hremoving the dependency on foreign (and thus expensive) developers and engineers. This simplification should ideally be achieved by providing a graphical interface to voice-service development.

The VSDK was evaluated during the ICT4D course at the Vrije Universiteit Amsterdam, where students built applications for various ICT4D use-cases using the VSDK. Afterwards a survey was conducted, which provided insight on the students’ experiences with voice-service development and the VSDK. From the results of the evaluation is concluded that the building-block approach to voice-service development used in the VSDK, is successful for the development of simple voice-services. It allows newcomers to (voice-service) development, to quickly develop (simple) voice-services from a graphical interface, without requiring programming experience.

The VSDK combined with the existing KasaDaka platform provides a good solution to the hosting and development of voice-services in the ICT4D context.

More details can be found in the complete thesis.A slidedeck is included below. You can find the VSDK code on Andre’s Github: http://github.com/abaart/KasaDaka-VSDK


Share This:

Machine-to-machine communication in rural conditions: Realizing KasadakaNet

[This post describes research by Fahad Ali and is based on his Msc. thesis]

Contextual constraints (lack of infrastructure, low-literacy etc.) play an important role in ICT for Development (ICT4D) projects. The Kasadaka project offers a technological platform for knowledge sharing applications in rural areas in Sub-Saharan Africa. However, lack of stable internet connections restrict exchange of data between distributed Kasadaka instances, which leads us to research alternative ways of machine-to-machine (m2m) communication.

Example of a KasadakaNet situation, with a wifi-donkey mounted on a bus, visiting a city and two remote villages, creating a so-called sneakernet

Fahad Ali’s research focuses on mobile elements and using wifi sneakernets for this m2m to enable information sharing between geographically distributed devices. He developed a Raspberry Pi-based device called the Wifi-donkey that can be mounted on a vehicle and facilitates information exchange with nearby devices, using the built-in wifi card of the rPi 3.The solution is based on Piratebox offline file-sharing and communications system built with free software and uses off-the-shelf Linux software components and configuration settings to allow it to discover and connect to nearby Kasadaka devices based using Wifi technologies.

Experimental setup: the wifi-donkey taped to an Amsterdam balcony to test range and bandwith.

We evaluated the solution by simulating a low resource setting and testing it by performing so-called “pass-bys” in an Amsterdam residential area. In these cases, SPARQL queries are exchanged between host and client devices and we measure amount of RDF triples transferred. This setup matches earlier case requirements as described in Onno Valkering’s work.Results show that the system works fairly reliably in the simulated setting. The machine-to-machine communication method can be used in various ICT4D projects that require some sort of data sharing functionality.

You can find out more about Fahad’s work through the following resources:

Share This:

Dancing and Semantics

This post describes the MSc theses of Ana-Liza Tjon-a-Pauw and Josien Jansen. 

As a semantic web researcher, it is hard to sometimes not see ontologies and triples in aspects of my private life. In this case, through my contacts with dancers and choreographers, I have since a long time been interested in exploring knowledge representation for dance. After a few failed attempts to get a research project funded, I decided to let enthusiastic MSc. students have a go to continue with this exploration. This year, two Information Sciences students, Josien Jansen and Ana-Liza Tjon-a-Pauw, were willing to take up this challenge, with great success. With their background as dancers they did not only have the necessary background knowledge at but also access to dancers who could act as study and test subjects.

The questions of the two projects was therefore: 1) How can we model and represent dance in a sensible manner so that computers can make sense of choreographs and 2) How can we communicate those choreographies to the dancers?

Screenshot of the mobile choreography assistant prototype

Josien’s thesis addressed this first question. Investigating to what extent choreographers can be supported by semi-automatic analysis of choreographies through the generation of new creative choreography elements. She conducted an online questionnaire among 54 choreographers. The results show that a significant subgroup is willing to use an automatic choreography assistant in their creative process. She further identified requirements for such an assistant, including the semantic levels at which should operate and communicate with the end-users. The requirements are used for a design of a choreography assistant “Dancepiration”, which we implemented as a mobile application. The tool allows choreographers to enter (parts of) a choreography and uses multiple strategies for generating creative variations in three dance styles. Josien  evaluated the tool in a user study where we test a) random variations and b) variations based on semantic distance in a dance ontology. The results show that this latter variant is better received by participants. We furthermore identify many differences between the varying dance styles to what extent the assistant supports creativity.

Four participants during the 2nd user experiment. From left to right this shows variations presented through textual, 2D animation, 3D animation, and auditory instructions.

In her thesis, Ana-Liza dove deeper into the human-computer interaction side of the story. Where Josien had classical ballet and modern dance as background and focus, Ana-Liza looked at Dancehall and Hip-Hop dance styles. For her project, Ana-Liza developed four prototypes that could communicate pieces of computer-generated choreography to dancers through Textual Descriptions, 2-D Animations, 3-D Animations, and Audio Descriptions. Each of these presentation methods has its own advantages and disadvantages, so Ana-Liza made an extensive user survey with seven domain experts (dancers). Despite the relatively small group of users, there was a clear preference for the 3-D animations. Based on the results, Ana-Liza also designed an interactive choreography assistant (IDCAT).

The combined theses formed the basis of a scientific article on dance representation and communication that was accepted for publication in the renowned ACE entertainment conference, co-authored by us and co-supervisor Frank Nack.

You can find more information here:

Share This:

ABC-Kb Network Insitute project kickoff

The ABC-Kb team, clockwise from top-left: Dana Hakman, Cerise Muller, Victor de Boer, Petra BosVU’s Network Institute has a yearly Academy Assistant programme where small interdisciplinary research projects are funded. Within these projects, Master students from different disciplines are given the opportunity to work on these projects under supervision of VU staff members. As in previous years, this year, I also participate as a supervisor in one of these projects, in collaboration with Petra Bos from the Applied Linguistics department. And after having found two enthusiastic students: Dana Hakman from Information Science and Cerise Muller from Applied Linguistics, the project has just started.

Our project “ABC-Kb: A Knowledge base supporting the Assessment of language impairment in Bilingual Children” is aimed at supporting language therapists by (re-)structuring information about language development for bilingual children. Speech language therapists and clinical linguists face the challenge of diagnosing children as young as possible, also when their home language is not Dutch. Their achievements on standard (Dutch) language tests will not be reliable indicators for a language impairment. If diagnosticians had access to information on the language development in the Home Language of these children, this would be tremendously helpful in the diagnostic process.

This project aims to develop a knowledge base (KB) collecting relevant information on the specificities of 60 different home languages (normal and atypical language development), and on contrastive analyses of any of these languages with Dutch. To this end, we leverage an existing wiki: meertaligheidentaalstoornissenvu.wikispaces.com

Share This:

DIVE+ in Europeana Insight

This months’ edition of Europeana Insight features articles from this year’s LODLAM Challenge finalists, which include the winner: DIVE+. The online article “DIVE+: EXPLORING INTEGRATED LINKED MEDIA” discusses the DIVE+ User studies, data enrichment, exploratory interface and impact on the cultural heritage domain.

The paper was co-authored by Victor de Boer, Oana Inel, Lora Aroyo, Chiel van den Akker, Susane Legene, Carlos Martinez, Werner Helmich, Berber Hagendoorn, Sabrina Sauer, Jaap Blom, Liliana Melgar and Johan Oomen

Screenshot of the Europeana Insight article

Share This:


This year, I was conference chair of the SEMANTiCS conference, which was held 11-14 Sept in Amsterdam. The conference was in my view a great success, with over 310 visitors across the four days, 24 parallel sessions including academic and industry talks, six keynotes, three awards, many workshops and lots of cups of coffee. I will be posting more looks back soon, but below is a storify item giving an idea of all the cool stuff that happened in the past week.

Share This:

“New life for old media” to be presented at NEM Summit 2017

The extended abstract “Investigations into Speech Synthesis and Deep Learning-based colorization for audiovisual archives” has been accepted for publication at the NEM (New NEM (cc-by circle ©heese https://www.flickr.com/photos/gratisdbth/7805513264)Eureopean Media) Summit 2017 to be held in Madrid end-of-November. This paper is based on Rudy Marsman’s thesis “Speech technology and colorization for audiovisual archives” and describes his research on using AI technologies in the context of an the Netherlands Institute for Sound and Vision. Specifically, Rudy experimented with developing speech synthesis software based on a library of narrated news videos (using the voice of the late Philip Bloemendal) and with the use of pre-trained deep learning colorization networks to colorize archival videos.

You can read more in the draft paper [PDF]:

Rudy Marsman, Victor de Boer, Themistoklis Karavellas, Johan Oomen New life for old media: Investigations into Speech Synthesis and Deep Learning-based colorization for audiovisual archives. Extended Abstract proceedings of NEM summit 2017

Update: the slides as presented by Johan Oomen at NEM

Share This:

Elevator Annotator: Local Crowdsourcing on Audio Annotation

[This post is based on Anggarda Prameswari’s Information Sciences MSc. Thesis]

For her M.Sc. Project, conducted at the Netherlands Institute for Sound and Vision (NISV), Information Sciences student Anggarda Prameswari (pictured right) investigated a local crowdsourcing application to allow NISV to gather crowd annotations for archival audio content. Crowdsourcing and other human computation techniques have proven their use for collecting large numbers of annotations, including in the domain of cultural heritage. Most of the time, crowdsourcing campaigns are done through online tools. Local crowdsourcing is a variant where annotation activities are based on specific locations related to the task.

The two variants of the Elevator Annotator box as deployed during the experiment.
The two variants of the Elevator Annotator box as deployed during the experiment.

Anggarda, in collaboration with NISV’s Themistoklis Karavellas, developed a platform called “Elevator Annotator”, to be used on-site. The platform is designed as a standalone Raspberry Pi-powered box which can be placed in an on-site elevator for example. It features a speech recognition software and a button-based UI to communicate with participants (see video below).

The effectiveness of the platform was evaluated in two different locations (at NISV and at Vrije Universiteit) and with two different modes of interaction (voice input and button-based input) through a local crowdsourcing experiment. In this experiments, elevator-travellers were asked to participate in an experiment. Agreeing participants were then played a short sound clip from the collection to be annotated and asked to identify a musical instrument.

The results show that this approach is able to achieve annotations with reasonable accuracy, with up to 4 annotations per hour. Given that these results were acquired from one elevator, this new form of crowdsourcing can be a promising method of eliciting annotations from on-site participants.

Furthermore, a significant difference was found between participants from the two locations. This indicates that indeed, it makes sense to think about localized versions of on-site crowdsourcing.

More information:

Share This:

Events panel at DHBenelux2017

At the Digital Humanities Benelux 2017 conference, the e-humanities Events working group organized a panel with the titel “A Pragmatic Approach to Understanding and Utilizing Events in Cultural Heritage”. In this panel, researchers from  Vrije Universiteit Amsterdam, CWI, NIOD, Huygens ING, and Nationaal Archief presented different views on Events as objects of study and Events as building blocks for historical narratives.

The session was packed and the introductory talks were followed by a lively discussion. From this discussion it became clear that consensus on the nature of Events or what typology of Events would be useful is not to be expected soon. At the same time, a simple and generic data model for representing Events allows for multiple viewpoints and levels of aggregations to be modeled. The combined slides of the panel can be found below. For those interested in more discussion about Events: A workshop at SEMANTICS2017 will also be organized and you can join!

Share This: