Cologne University of Applied Sciences

Master Programme

Blockchain, Cryptocurrencies and Web Trust

 By R. Butz and B. Krumnow
Starting in the early 1990s, cryptographers tried to develop ways in order to realise the concept of “money” in electronic form. David Chaum developed one of the first electronic currencies called ecash, which aimed to keep its users anonymous [1, 2]. The anonymity was achieved with blind signatures. These allowed users to obtain an untraceable digital currency from a bank and spend it. In later versions, it was even possible to allow offline transactions without double-spending. However, with Chaum being too greedy ecash was forgotten soon. After other brief experiments with digital money, pure forwarding services such as PayPal prevailed over electronic currencies. 
Over the last years, the interest and investments in cryptocurrencies has been rapidly growing. Bitcoin alone experienced a massive price increase from $1,000 USD a coin to temporarily over $19,000 USD in 2017 [3]. This can be seen as sign for a wider acceptance and also as a big success of this technology. However, the new interest in cryptocurrency is not only financially motivated. The Blockchain, the underlying technology of cryptocurrencies as Bitcoin, renewed the idea to decentralise digital systems. In fact, the original intension of Bitcoin was to solve a trust-based issue within the online merchandise domain [4]. Traditionally, trading parties had to rely on middlemen, such as banks and payment service providers, in order to perform transactions. This involvement makes transactions reversible and led middlemen to collect unnecessary information about traders. By moving transactions into a blockchain cryptographic proof about transactions are always provided. This creates a foundation for systems, whereby there is no need for central parties or middlemen to authenticate transactions. 
Applying the concept of the Blockchain to other areas, makes a transition towards a more centralised Web within the next few years a more feasible proposition. 

Didactical concept

The goal to design a workshop to teach the concept of blockchains contains some obstacles. The basic concepts are complex materials of computer science and their applications within Blockchain, concepts such as peer-to-peer-systems and cryptography must first be established. Furthermore, the Web sicence programme at TH Köln defines a 3 hours length for online workshops. Students can quickly be overwhelmed with these concepts within a single workshop. Luckily, there are plenty of materials available to students, such as books, MOODS and video blogs. All of which aid understanding these concepts outside the classroom. 
We kept these things in mind, when designing our workshop. It addresses not only technical fundamentals but also the application of blockchain in practice. The current design is sperated into 3 parts. The first part of the course makes participants familiar with basic concepts and can be done at home. It encompasses an exercise, which consists of a fun-based hacking challenge with the aim build on basic hash functions. Followed by some basic reading materials and questions about asymmetric cryptography and cryptographic hash functions. Within the classroom environment students clarify questions together with the lecturers and dive into the concept of Bitcoin and blockchains. In additon, students learn which opportunities the technologies hold and what it means to web trust then they work on real life problems and attempt to address them with bitcoin or ethereum. All the results are presented in a poster session at the final on-site session, which rounds up the discussions from the workshop.


  1. Untraceable Electronic Cash – David Chaum and Amos Fiat and Moni Naor, Advances in Cryptology – CRYPTO ’88, 8th Annual International Cryptology, Conference, Santa Barbara, California, USA, August 21-25, 1988, Proceedings, 319-327, 1988
  2. Chaum, David. “Blind signatures for untraceable payments.” In Advances in cryptology, pp. 199-203. Springer, Boston, MA, 1983.
  3. Nakamoto, Satoshi. “Bitcoin: A peer-to-peer electronic cash system.” (2008).
  4. Bitcoin USD price – Coindesk,, last seen 7th May 2018

May 8, 2018 | | Benjamin Krumnow

Master Thesis: Designing Worth in a Connected World: A Conceptual Approach for Participatory Design with a Focus on Values

Georg Schröder recently submitted and successfully presented his Master thesis “Designing Worth in a Connected World”, which was supervised by Prof. Dr. Gerhard Hartmann and Christiane Grünloh. We asked him to provide a short summary of his thesis for our blog:


Designing Worth in a Connected World: A Conceptual Approach for Participatory Design with a Focus on Values

by Georg Schröder

The master thesis introduces a new conceptual model for the design of web technology based on the concepts of worth and values. Using the holistic perspective of Web Science, the model not only takes users’ needs into account but also the demands of their social and cultural environment in order to facilitate the creation of better, more successful, as well as more responsible systems.
Since web technologies change and shape the world profoundly, it is important to take the positive and negative consequences into account that new systems might have for the environments in which they are embedded. The work investigates on a conceptual level how a relevant design approach that builds on the idea of making worth and values a main concern for the development of computer technology can be put into practice.

Worth, value, and values
First, the abstract concepts of worth, value and values are illuminated. Although these terms are frequently used in literature they are hardly defined and not used in a consistent way. Therefore, definitions are given followed by a conceptualization. Further, it is shown in which dimensions values generally can reside in order to provide guidance for their identification. On a high level there are economic, social, cultural, political, ecological as well as moral and ethical value dimensions that may all be potentially relevant in a design case. This diversity illustrates that an interdisciplinary approach is needed when values are concerned in design. The first part of the thesis ends with a demonstration on how values come to life in computer technology. By means of examples it is illustrated that values reside on every technical level in ICT and it is argued that technology is always value-laden no matter whether values have been an explicit concern in the development process or not.

Values- or worth-oriented design methodologies
The second part of the thesis presents the results of a literature research about existing values- or worth-oriented design methodologies.  Here, a couple of approaches were found, which differ in their perspectives and main priorities and which have different theoretical and practical substance. Overall, Value Sensitive Design (VSD) [4], Designing Worth (DW) [1,2] and Participatory Design (PD) [5] were identified as sophisticated methodologies that offer enough substance to be put into practice and to which many other approaches can be referred to. Each approach has a specific emphasis and it was found that none of them covers all aspects relevant to put a holistic worth- or values-oriented design of web technology into practice.

Comparing key principles
In the third chapter, a comparison of the approaches’ key principles is made, which illustrates relationships, overlaps, and differences of the approaches in a systematic way. Finally, a new conceptual design model is introduced, based on the idea to combine the elements from PD, DW and VSD into a new approach that can fill the gaps and shortcomings of the individual methodologies and thus brings designing for worth and values one step further.

Conceptual Approach with a Focus on Worth and Values
The proposed design model builds on the Worth Development Framework from Cockton [3] but is enhanced by a further process and refined by the inclusion of resources like Worth Maps and Value Stories.


Design model derived from Cockton [6], extended with an additional process “Understanding” and complemented with design/development artefacts and activities.

Thereafter, the design work is divided into five processes: Understanding for the pre-determination of human values, Opportunity Identification for the identification of stakeholders and values elicitation, Design and Evaluation that are closely intertwined and performed concurrently and, finally, Iteration that investigates design defects by causal analysis and determines targets for iteration. The practical design work is dominated by methods, tools and techniques from PD, which are well suited to elicit abstract and subjective values and worth and therefore represent the heart of the approach. VSD contributes with a focus on human values with ethical support and the stakeholder concept.

How far the proposed approach will work in practice has still to be proven. Nevertheless, it is a proposal which is theoretically founded on contemporary research and therefore it seems to be feasible and promising. At least, it contributes to the ongoing discourse and further advancement in the development of such web technologies that are not limited to the fulfilment of narrow and short-sighted interests but instead facilitates to create smarter, more successful and sustainable as well as responsible systems and thus helps to create a Web we want.

If you have questions about this approach, you can contact Georg Schröder via email:
info (at)


[1] Cockton, Gilbert: Value-centred HCI. In: Proceedings of the third Nordic conference on Human-computer interaction ACM, 2004, pages 149–160
[2] Cockton, Gilbert: Designing worth is worth designing. In: Proceedings of the 4th Nordic conference on Human-computer interaction: changing roles ACM, 2006, pages 165–174
[3] Cockton, Gilbert: A development framework for value-centred design. In: CHI’05 extended abstracts on Human factors in computing systems ACM, 2005, pages 1292–1295
[4] Friedman, Batya; Jr, Peter H.; Borning, Alan: Value Sensitive Design and Information Systems. In: The Handbook of Information and Computer Ethics (2008), pages 69–101
[5] Simonsen, Jesper; Robertson, Toni: Routledge international handbook of participatory design. Routledge, 2012
[6] Cockton, Gilbert: What worth measuring is. In: International Workshop on, 2008, pages 60–66


November 21, 2017 | | Christiane Grünloh

Learning about Research through Podcasts

Picture by @neilgodding

Research methods: There is so much to love about them, for example that they can guide you in a systematic way to find an answer to your research question. As a master student, it can however be pretty frustrating. For example, when your lecturer asks you to come up with a research design for a problem you just started to think about, including the selection of appropriate methods, which you maybe just have learned about the other week in a lecture.

Research approaches and methods are often presented in a quite abstract or brief way, especially when you read articles published in conference proceedings, as the authors have to adhere to the page limitations. There are many excellent books on research methods, but maybe an even more fun way to learn about research studies, their design, the used methods and the findings is to listen to the researchers talking about it in podcasts.

Podcast: You Are Not So Smart by David McRaney

One of my favorite Podcasts is You Are Not So Smart by David McRaney. In his blog and podcast, he explores “self delusion” and the central theme of his podcast is “that you are unaware of how unaware you are”. In the very first episode, he talks about “attention” and interviews Daniel Simons, one of the researchers behind the Monkey Business Illusion, which you might have seen before. For me, it is super interesting to listen to the researchers explaining what happened behind the scenes, in other words how they set up their experiments or studies, their rationales behind it, and what they found. At the end of each podcast „there will be cookies“ and an read-out abstract from a related study.

The podcast is really great and I personally learned a lot about many phenomena. Take for example the backfire effect (episode 93-95), which is highly relevant also in relation to “fake news” and other issues we face today. I listened to all episodes by now and highly recommend to start with the first episode. By listening to them, not only will you learn specific aspects about certain phenomena, but also increase your general knowledge about research, research methods, the language researchers use to explain what they do (i.e., the specific terms used), how a research design might be set up, things to consider and so on.

Podcast: Everything Hertz by Dan Quintana and  James Heathers

I recently came across the Everything Hertz podcast which is described as “A podcast by scientists, for scientists. Methodology, scientific life, and bad language. Co-hosted by Dr. Dan Quintana and Dr. James Heathers”. I listened to episode 46, because here they interview Andy Field. Andy is the author of the “Discovering Statistics” textbook series and – no kidding – a science fiction novel on statistics. The latter is on my pile of books that are yet to read for far too long:

As Andy Field says in the podcast, everyone has to find the resources that speaks to them. So his books may not be for you; I personally like his writing style and used his books when preparing my lecture on research methods. So whatever you choose, as soon as you start reading research papers, books on research methods, or listening to podcasts talking about research, you might realize that there is a lot to think about before carrying out a study. In line with David McRaney’s theme: You don’t know, what you don’t know. So why not give it a try and start making use of those podcasts?

November 2, 2017 | | Christiane Grünloh

Master Thesis: Determinants and Success Factors that Influence the User Adoption of Mobile Payments in Germany

Adeteju Enunwa recently submitted and successfully presented her Master thesis about the determinants and success factors that influence user adoption of mobile payments in Germany. We asked her to provide a short summary of her thesis for our blog:


Determinants & Success Factors that Influence the User Adoption of Mobile Payments in Germany

By Adeteju Enunwa

Research Model inspired by the “Unified Theory of Acceptance and Use of Technology” (UTUAT) model by Venkatesh et al. [1] and “Diffusion of Innovations” Theory by Rogers [2].

The swift adoption of smart phones globally has impacted various industries, thus  resulting in an explosion of mobile applications being used for the execution of various tasks across all sectors of the economy. The emergence of financial technology firms (Fintechs) who have redefined banking and payment has also resulted in an evolution in the way proximity based payments are made, with a gradual shift from cash, to contact only cards, to Dual Interface (DI) cards which supports contactless payments and now to mobile payments. Although, the payment scene has welcomed the presence of additional stakeholders such as Mobile Network Operators (MNOs) and Smart phone manufacturers e.g. Apple, Samsung with the evolution in NFC payments, mobile payments remains at a stagnant level with little or no growth in the adoption rate in Germany when compared to other European countries such as France, United Kingdom, Spain etc. where contactless is gradually the new alternative to cash.

The conceptual model was tested using two qualitative research methods namely: Observation and Interviews to carry out the study. The Observation phase was carried out over a period of five (5) days at a canteen in Munich, whereby the mode of payments of an average of one hundred and twenty (120) people were observed daily. Afterwhich, interviews were conducted to enable the researcher ascertain the factors that influence the intention to use and adopt mobile payments.

During the study, it was revealed that Data Privacy and Security were the core factors that would influence the intension to use mobile payments. Interestingly cost was an additional factor that also impacted the user’s perception on usefulnesses which was derived by comparing the value added offerings and associated cost to existing alternatives.

Due to the sample size, there were some limitations based on the location and the fact that most participants interviewed were male, thereby social factors such as the influence of gender could not be explored. However, two core external factors beyond the control of the end user were identified as the major challenges facing the adoption of mobile payments in Germany. (1) The inexistent support and specification standards for mobile payments by the domestic network known as girocard and (2) the poor acceptance by merchants. A strategic collaboration among stakeholders of the payment industry will be required if mobile payments is to be successful in Germany. The average end user must be confident enough to visit any merchant without the fear of limited acceptance for contactless payments


  1. Venkatesh, V., Morris, M., Davis, G., & Davis, F. (2003). User Acceptance of Information Technology: Toward a Unified View. MIS Quarterly, 27(3), 425-478. Retrieved from
  2. Rogers, Everett M. (1995). Diffusion of innovations. The Free Press, Connecticut, USA.

September 4, 2017 | | Christiane Grünloh

Web Science Graduate receives Opitz Innovation Award

Web Science Graduate Cagdas Cumhur Ünlüer received the first price of the Opitz Innovation Award for his Master Thesis “Characteristics for intelligent food packages and Internet of Things solutions based on conditions for food waste in Germany”. In his Thesis Cagdas Cumhur Ünlüer designed an IoT approach for a reduction of food waste. The general idea of deploying intelligent food packages is founded on quantity structures and well defined technical and economical concepts.

The corresponding German press release can be found here.

July 11, 2017 | | Christiane Grünloh

Getting your Master of Science without quitting your job!

Did you ever think about getting back to University to earn your Master of Science? Lifelong learning is essential, especially in a world that is constantly changing. Then some questions might come up: But what about my job? Where would I live and how would I be able to pay for this? Okay, there may be some online programmes, but a) how credible are these and b) would I really be motivated to learn all this on my own as self-study?

Web Science at TH Köln

We designed our Master programme in Web Science so that you would neither have to quit your job nor have to move. It is designed for students, who work full-time and want to pursue their Master of Science degree in part-time.

2 on-site weekends in Cologne, combined with eLearning and interactive online sessions

Web Science Master programme combines on-site and online sessions

To make this feasible, the programme is mainly held online, but we start and end each semester with an on-site weekend. During the first weekend, lectures are held and project teams are formed. And as we heard, the students meet in the evenings and exchange experiences and get to know each other. This is also very important as during the semester most of the students will mainly meet online when working together in their projects.

During the semester, every Tuesday and Thursday online sessions for the courses are held in the evenings (19.00 – 22.00 o’clock). Often the students have to prepare some small exercises in advance, read specific literature, or watch online lectures. In that way, the online sessions can be highly interactive, where students e.g. work together in smaller groups on a given task, which is then discussed in class together with the lecturer. This makes it possible for students to apply directly what they learned, engage in discussions (which also supports deeper understanding), and get immediate feedback. In modules which include a project these online sessions are also used to discuss the progress, challenges and opportunities of the project. Individual feedback is very important, so that the students can improve their project constantly throughout the semester. Interactive sessions, working together in groups, engaging in discussions and receiving individual feedback is something that differentiates the Web Science Programme from others online programmes in which students mainly have to study on their own. Self-study may not be that motivating and when there is increased stress at work, it may be very tempting to postpone it. Like the membership in the gym, where you for sure start practicing again next week 😉 . We can see that the students in our programme are highly motivated, work really well together, and help each other.

During the last weekend in each semester, the second on-site meeting is held. Here, the students will have their exams, which can be a written exam or a project presentation. It is always exciting; not only due to the exams, but also to see the final results of the often very interesting projects.

Answering the questions

So what about the “But, …” questions mentioned at the beginning? I think we addressed these in our programme:

  • But what about my job? Where would I live and how would I be able to pay for this?

You can keep your job and thus won’t loose your income. You wouldn’t have to move, because we only have two on-site weekends per semester, so for most students it is feasible to travel for those weekends to Cologne.

  • Online programmes: How credible are these? 

Our programme has be examined by the independent and professional agency AQAS. The accreditation of our Web Science Master programme has been successfully renewed until 2023.

  • Would I really be motivated to learn all this on my own as self-study?

Although you may have to work on some exercises or read literature on your own, you mostly have meetings together with peers or work in teams, which makes it easier to focus and to stay motivated.

So, what are you waiting for? Apply now 🙂



June 7, 2017 | | Christiane Grünloh

Social Media Seminar with Challenging Topics

The Masters programme „Web Science“ at the Cologne University of Applied Sciences (TH Köln) covers in this year’s Advanced Seminar ( a broad and challenging spectrum of topics: Social Media are kind of an umbrella for more detailed coverage of aspects like user behaviour, governance, security, and privacy. Great research contributions could be discovered at conferences like the acm Web Science Conference ( or the World Wide Web Conference (

The Advanced Seminar is part of the module „Web Project Development“ in the online extraoccupational Masters programme ( The seminar is held with frequent discussions and cooperations online in the evenings during the semester, and a poster session on a Saturday in July in Cologne (Südstadt) ending the semester work.

May 17, 2017 | | Kristian Fischer

New publication by Christian Klemm and Wolter Pieters

Christian Klemm published together with Dr. Wolter Pieters an article in Ethics and Information Technology. The article “Game mechanics and technological mediation: an ethical perspective on the effects of MMORPG’s” argues that discussions around video games should not only include the effect of their content (e.g. violence) but should also consider the effects of game mechanics. They analyzed ethical dimensions of behavioral game design and conclude with proposals for a better design. The paper is published as Open Access and is available here.

Christian Klemm graduaded in our Web Science programme in 2016. Dr. Wolter Pieters is assistant professor at TU Delft and was a lecturerer in Computer Ethics in our programme until 2015.


February 2, 2017 | | Christiane Grünloh

Successful reaccreditation of the Web Science Programme at TH-Köln

The accreditation of our Master-Programme in Web Science has successfully been renewed  until 30th of September 2023.

December 15, 2016 | | Gerhard Hartmann

Renaming Cologne University of Applied Sciences in: TH Köln – University of Applied Sciences

As of September 1, Cologne University of Applied Sciences will be known as Technische Hochschule Köln – abbreviated as TH Köln – bearing a new logo.

Information about why we have decided to take this step and how the renaming will affect students can be found in this letter.

October 29, 2015 | | Christiane Grünloh

Web Science 2016 Conference

The 8th International ACM Web Science Conference 2016 will be held from May 22 to May 25, 2016 in Hannover, Germany. For more information visit

October 12, 2015 | | Christiane Grünloh

The 9th International IFIP Summer School on Privacy and Identity Management for the Future Internet in the Age of Globalisation

The 9th International IFIP Summer School on Privacy and Identity Management for the Future Internet in the Age of Globalisation will take place on 7-12 September, 2014 in Patras, Greece.

This is always a fantastic opportunity to spend a working week with well-known and high-level researchers and theorists, and also – as someone new to the field – to get great feedback on your work and maybe to have the possibility of contributing to a book publication.

The IFIP Summer School 2014 is interactive in character, and is composed of keynote lectures and workshops with master/PhD student presentations. While the website indicates 10 June 2014 as the abstract submission date, according to the organizers there is surely still time available for student sociologists, social scientists, anthropologists and ethicists to submit!

June 10, 2014 | | Christiane Grünloh

First Web Science Summer School in Southampton, UK

The University of Southampton will host the first Web Science Summer School this year from 20. to 26. July. You will get the chance to listen and talk to the invited speakers Wendy Hall, Jim Hendler, Cory Doctorow, Chris Welty, and Guus Schreiber and network with other Masters and PhD students.

See more information regarding the programme, the speakers and tutors here:

The summer school requires a registration fee (€ 670). Registration is possible until 13.06.2014.

May 7, 2014 | | Christiane Grünloh

Apply now

The CUAS application portal is open – so feel free to apply directly: CUAS online application platform.

International applicants have to register online with uni-assist and enter your uni-assist application number in the CUAS platform.

You find more detailed information here.

May 5, 2014 | | Christiane Grünloh

German Language Modules for International Students in the Summer Semester 2014

The Language Learning Centre of FH Köln offers German language classes for international students in the upcoming summer term.

Further information are available here:

February 7, 2014 | | Christiane Grünloh

Screening and panel discussion
“Work Hard – Play Hard”

There will be a screening of the documentary “Work Hard – Play Hard” and a subsequent panel discussion about new forms of labour organization (probably in German) at Filmclub 813 e.V., Hahnenstr. 6, 50667 Köln.

For more information visit:

August 13, 2013 | | Christiane Grünloh

Deadline for International Applicants approaching –
apply NOW!

The deadline for international applications for the upcoming winter term ends on June 30th. Since the application process via uni assist takes some time, the sooner you submit your documents, the better. The first on-site weekend in winter term will take place on 20.-22. September 2013.

Students with foreign certificates have to apply via Uni-Assist. Please take also a look at theHelp-Site of Uni-Assist and follow every step. This is very important, since otherwise some important steps might be forgotten and will then hinder the application process. Unfortunately there is not that much time left, so if you want to apply please make sure, that you

  • upload all important documents at once to uni assist
  • send the certificates also paper-based
  • pay the uni-assist fee

Otherwise uni-assist won’t proceed your application.

August 13, 2013 | | Christiane Grünloh