PhD Tourism

One of the perks as a PhD student is attending conferences and workshops at many places in the world. First of all, this gives you the chance to meet interesting people from all over the world, present research results and discuss with people (not only) about work. Apart from these professional benefits and the personal development, visiting such venues gives you the chance to visit countries you might not have been to before. And, although, being linked with some bureaucracy, it is often possible to combine such a business trip with a few days of holiday. Thus, these travels compensate for the, compared to industry standards in computer science, low salary of a PhD student. Especially for someone as me, who loves taking photos, this is a very nice compensation for the long hours working to get the papers accepted.

While the title of this section was chosen rather provocatively, its message is not too far-fetched in my case. First of all, I was lucky enough to get several papers excepted during my time as a PhD student (cf. with my list of publications). Secondly, most of these papers were submitted to venues at places where I have never been before and my supervisor allowed me to visit them despite the costs. And lastly, my supervisor always gave me the chance to add a few personal days before or after the venue. In fact, in one case, we organized a road trip together and visited Kruger National Park in South Africa with two other colleagues.

To be clear about the intention of this post: I am not promoting to start a PhD just because you like traveling. Being a PhD student is oftentimes a tough job (especially when working towards a deadline). Thus, your personal interest in professional and personal development should be the number one priority when starting a PhD. However, in my opinion, embracing the additional opportunities to not only learn more about your proficiency, but also about other countries and cultures is just sensible.

On this page, I will give a short overview of all business related trips during my PhD together with venue, the accepted paper and a link to photos that I took during the trip. The list’s intention is mostly to keep a summary for personal purposes. However, I also thought that it might be interesting for people visiting my website and wondering where all the pictures were taken (apart from my vacation trips).

Tokio 2013

Tuna at the Tsukiji fish market
Tuna at the Tsukiji fish market

Venue: International Workshop on Model-Driven Approaches in Software Product Line Engineering (MAPLE) at the International Software Product Line Conference (SPLC), Tokyo, Japan

Comment: This was my first publication as a first author and was published before I finished my Master of Science in 2014 and started my PhD in 2015. In addition, this was my first visit to Japan, which I enjoyed a lot and made me come back a few times in the following years.

Photography: Japan gives a lot of nice opportunities to take pictures, because the culture is so different from Europe. Especially the Tsukiji fish market in Tokyo is a place that fascinates me. Sadly, it was closed in October 2018.

Link to the Photos

  • [DOI] D. Wille, S. Holthusen, S. Schulze, and I. Schaefer, “Interface Variability in Family Model Mining,” in Proc. of the Intl. Workshop on Model-Driven Approaches in Software Product Line Engineering (MAPLE), 2013, p. 44–51.
    [Bibtex] [Publisher Page] [Abstract]

    Model-driven development of software gains more and more importance, especially in domains with high complexity. In order to develop differing but still similar model-based systems, these models are often copied and modified according to the changed requirements. As the variability between these different models is not documented, issues arise during maintenance. For example, applying patches becomes a tedious task because errors have to be fixed in all of the created models and no information about modified and unchanged parts exists. In this paper, we present an approach to analyze related models and determine the variability between them. This analysis provides crucial information about the variability (i.e., changed parts, additional parts, and parts without any modification) between the models in order to create family models. The particular focus is the analysis of models containing components with differing interfaces.

    @inproceedings{WHS+13,
    author = {Wille, David and Holthusen, S{\"{o}}nke and Schulze, Sandro and Schaefer, Ina},
    title = {{Interface Variability in Family Model Mining}},
    booktitle = {{Proc. of the Intl. Workshop on Model-Driven Approaches in Software Product Line Engineering (MAPLE)}},
    year = {2013},
    pages = {44--51},
    doi = {https://dx.doi.org/10.1145/2499777.2500708},
    publisher = {ACM},
    abstract = {Model-driven development of software gains more and more importance, especially in domains with high complexity. In order to develop differing but still similar model-based systems, these models are often copied and modified according to the changed requirements. As the variability between these different models is not documented, issues arise during maintenance. For example, applying patches becomes a tedious task because errors have to be fixed in all of the created models and no information about modified and unchanged parts exists. In this paper, we present an approach to analyze related models and determine the variability between them. This analysis provides crucial information about the variability (i.e., changed parts, additional parts, and parts without any modification) between the models in order to create family models. The particular focus is the analysis of models containing components with differing interfaces.}
    }

Schloss Dagstuhl 2014

Schloss Dagstuhl
Schloss Dagstuhl

Venue: International Feature-Oriented Software Development (FOSD) Meeting, Schloss Dagstuhl – Leibniz Center for Informatics, Dagstuhl, Germany

Comment: During my Master’s thesis, I was invited to the FOSD Meeting at Schloss Dagstuhl. Schloss Dagstuhl is (at least in academic computer science) known for the Dagstuhl Seminar series, which brings researchers from specific areas together for informal meetings to talk about future research directions and to exchange new ideas. The informal FOSD Meeting allowed me to present the ideas of Master’s thesis in front of a scientific audience and to get valuable feedback on my ideas.

Photography: In the evening, I was able to take a few pictures during walks on the compound of Schloss Dagstuhl.

Link to the Photos

Hong Kong & Macau 2014

Sunset over Hong Kong Island
Sunset over Hong Kong Island

Venue: Student Research Competition at the International Symposium on the Foundations of Software Engineering (FSE), Hong Kong

Comment: Shortly before handing in my Master’s thesis in November 2014 and starting my job as a PhD student in January 2015, this paper was accepted at the Student Research Competition. As a result, this business trip gave me the chance to unwind from them six month of writing my Master’s thesis. In addition, I was able to visit Macau by taking a speed boat from Hong Kong . As Macau is a former Portuguese colony, it has a completely different flair than former British colony Hong Kong.

Photography: Similar to Japan, you get a lot of unfamiliar impressions in Hong Kong. What striked me most is that the busy downtown and the quiet islands are just a short ferry ride apart.

Link to the Photos of Hong Kong

Link to the Photos of Macau

  • [DOI] D. Wille, “Managing Lots of Models: The FaMine Approach,” in Proc. of the Intl. Symposium on the Foundations of Software Engineering (FSE), 2014, p. 817–819.
    [Bibtex] [Publisher Page] [Abstract]

    In this paper we present recent developments in reverse engineering variability for block-based data-flow models.

    @inproceedings{Wil14,
    author = {Wille, David},
    title = {{Managing Lots of Models: The FaMine Approach}},
    booktitle = {{Proc. of the Intl. Symposium on the Foundations of Software Engineering (FSE)}},
    year = {2014},
    pages = {817--819},
    doi = {https://dx.doi.org/10.1145/2635868.2661681},
    publisher = {ACM},
    abstract = {In this paper we present recent developments in reverse engineering variability for block-based data-flow models.}
    }

Oslo 2015

Fountain (long exposure)
Fountain (long exposure)

Venue: International Symposium on Formal Methods (FM), Oslo, Norway

Comment: Although, I did not have an accepted paper, I registered for a tutorial on correctness-by-construction development of algorithms. While the tutorial was canceled, I met with a research partner from University of Technology Eindhoven (The Netherlands) for a work meeting. In the long-term, this new acquaintance developed into a fruitful collaboration.

Photography: Although being very expensive, Oslo is really nice city with an interesting mixture of modern buildings (e.g., the opera house) and old buildings (e.g., the royal palace). Thus, a lot of photo opportunities exist.

Link to the Photos

Ōsaka & Kyōto 2016

Street in Ōsaka
Street in Ōsaka

Venue: International Conference on Software Analysis, Evolution, and Reengineering (SANER), Ōsaka, Japan

Comment: This was my first conference publication as a first author and was a result of generalizing the approach developed for reverse-engineering variability in MATLAB/Simulink models and statecharts. For the first part of my vacation, I explored different parts of Ōsaka. In addition, I spent a couple of nights in Kyōto

Photography: Ōsaka is a nice city to enjoy good japanese food as it is often referred to as the foody town of Japan. Kyōto, on the other hand, is much more interesting with regard to culture and sights as it is famous for its temples and shrines. Thus, many interesting opportunities for taking photos can be found in Kyōto.

Link to the Photos of Ōsaka

Link to the Photos of Kyōto

  • [DOI] D. Wille, S. Schulze, C. Seidl, and I. Schaefer, “Custom-Tailored Variability Mining for Block-Based Languages,” in Proc. of the Intl. Conference on Software Analysis, Evolution, and Reengineering (SANER), 2016, p. 271–282.
    [Bibtex] [Publisher Page] [Abstract]

    Block-based modeling languages, such as MATLAB/Simulink or state charts, reduce the complexity inherent to developing large-scale software systems. When creating variants for largely similar yet different software systems, the common practice is to copy models and modify them to different requirements. While this allows companies to save costs in the short-term, these so-called clone-and-own approaches cause problems regarding long-term evolution and system quality as the relation between the variants of the resulting software family is lost so that the variants have to be maintained in isolation. To recreate information regarding the variants’ relations, variability mining identifies common and varying parts of cloned variants but, currently, the respective algorithms have to be created for each target language individually. In this paper, we present a generalized method to instantiate variability mining for arbitrary block-based modeling languages. The identified variability information allows developers to understand the variability of their grown software family. This knowledge helps efficiently maintaining the variants and allows migrating from clone-and-own approaches to more elaborate reuse strategies, such as software product lines. We demonstrate the feasibility of our method by instantiating variability mining techniques for two block-based languages.

    @inproceedings{WSS+16,
    author = {Wille, D. and Schulze, S. and Seidl, C. and Schaefer, I.},
    title = {{Custom-Tailored Variability Mining for Block-Based Languages}},
    booktitle = {{Proc. of the Intl. Conference on Software Analysis, Evolution, and Reengineering (SANER)}},
    year = {2016},
    volume = {1},
    pages = {271--282},
    doi = {https://dx.doi.org/10.1109/SANER.2016.13},
    publisher = {IEEE},
    abstract = {Block-based modeling languages, such as MATLAB/Simulink or state charts, reduce the complexity inherent to developing large-scale software systems. When creating variants for largely similar yet different software systems, the common practice is to copy models and modify them to different requirements. While this allows companies to save costs in the short-term, these so-called clone-and-own approaches cause problems regarding long-term evolution and system quality as the relation between the variants of the resulting software family is lost so that the variants have to be maintained in isolation. To recreate information regarding the variants' relations, variability mining identifies common and varying parts of cloned variants but, currently, the respective algorithms have to be created for each target language individually. In this paper, we present a generalized method to instantiate variability mining for arbitrary block-based modeling languages. The identified variability information allows developers to understand the variability of their grown software family. This knowledge helps efficiently maintaining the variants and allows migrating from clone-and-own approaches to more elaborate reuse strategies, such as software product lines. We demonstrate the feasibility of our method by instantiating variability mining techniques for two block-based languages.}
    }

Eindhoven 2016

Old Bicycle at the NDSM Wharf
Old Bicycle at the NDSM Wharf

Venue: 

Comment: This visit to Eindhoven was not related with any publication or venue, but to start a collaboration with colleagues from University of Technology in Eindhoven. After finishing work in Eindhoven, I made a detour to Amsterdam on my way back to Germany and spent my birthday there.

Photography: Although Eindhoven is a nice small city, I did not have much time to take photos here as I mainly worked with the colleagues. Instead, I took photos in Amsterdam during my vacation.

Link to the Photos of Amsterdam

Ede 2016

Hoge Veluwe Park
Hoge Veluwe Park

Venue: Winter School: “Big Software on the Run: Where Software meet Data”, Ede, The Netherlands

Comment: The winter school was very interesting and I learned a lot about other research fields (e.g., business process mining and data visualization) that are loosely related with my research. In addition, the winter school offered the chance to meet interesting young researchers and seniors to discuss about different research areas. For my poster presented during the poster session, I received the Best Poster Award and I was given the chance to give a presentation of my research.

Photography: Ede is small dutch town that does not have many famous sights. However, during the excursion to the close-by Hoge Veluwe Park (a dutch national park famous for its heather), I took a few pictures.

Link to the Photos of the Hoge Veluwe Park

Amsterdam 2016

Bike
Bike

Venue: International Workshop on Feature-Oriented Software Development (FOSD) at the International Conference on Systems, Programming, Languages and Applications: Software for Humanity (SPLASH), Amsterdam, The Netherlands

Comment: Directly after the winter school in Ede, I presented a paper at the FOSD workshop in Amsterdam. As the workshop started on Sunday, I had the day off on Saturday and was able to spent some time in Amsterdam. Most of the colleagues from the institute joined me on Sunday either because they had papers accepted at the FOSD workshop or the International Conference on Generative Programming: Concepts & Experience (GPCE) colocated with SPLASH. As we rented a whole house for the stay, this visit to Amsterdam felt a lot like a class trip.

Photography: During my day off on Saturday, I explored Amsterdam and took a few pictures of the canals.

Link to the Photos

Corfu 2016

Sunrise
Sunrise

Venue: International Symposium on Leveraging Applications of Formal Methods, Verification and Validation (ISoLA), Corfu, Greece

Comment: Due to a strike of the Greek air traffic controllers, my colleague and me canceled our flights. However, on the next day, the air traffic controllers also canceled their strike. Thus, we booked new flights in the afternoon for the next morning and left one hour later for the train station. We took a train from Braunschweig to Cologne and spent the night at the airport to take the plane early in the morning. This was one of the most exhausting business trips, but we were rewarded with a very nice hotel, good food and one relaxing afternoon at the hotel beach.

Photography: We had booked a guided tour of Corfu town and saw the famous Kanoni Church on our way. Overall, the island offers a nice landscape and different opportunities to take interesting pictures.

Link to the Photos

  • [DOI] D. Wille, M. Tiede, S. Schulze, C. Seidl, and I. Schaefer, “Identifying Variability in Object-Oriented Code Using Model-Based Code Mining,” in Proc. of the Intl. Symposium on Leveraging Applications of Formal Methods, Verification and Validation (ISoLA), 2016, p. 547–562.
    [Bibtex] [Publisher Page] [Abstract]

    A large set of object-oriented programming (OOP) languages exists to realize software for different purposes. Companies often create variants of their existing software by copying and modifying them to changed requirements. While these so-called clone-and-own approaches allow to save money in short-term, they expose the company to severe risks regarding long-term evolution and product quality. The main reason is the high manual maintenance effort which is needed due to the unknown relations between variants. In this paper, we introduce a model-based approach to identify variability information for OOP code, allowing companies to better understand and manage variability between their variants. This information allows to improve maintenance of the variants and to transition from single variant development to more elaborate reuse strategies such as software product lines. We demonstrate the applicability of our approach by means of a case study analyzing variants generated from an existing software product line and comparing our findings to the managed reuse strategy.

    @inproceedings{WTS+16,
    author = {Wille, David and Tiede, Michael and Schulze, Sandro and Seidl, Christoph and Schaefer, Ina},
    title = {{Identifying Variability in Object-Oriented Code Using Model-Based Code Mining}},
    booktitle = {{Proc. of the Intl. Symposium on Leveraging Applications of Formal Methods, Verification and Validation (ISoLA)}},
    year = {2016},
    series = {Lecture Notes in Computer Science},
    volume = {9953},
    publisher = {Springer},
    doi = {https://dx.doi.org/10.1007/978-3-319-47169-3_43},
    pages = {547--562},
    abstract = {A large set of object-oriented programming (OOP) languages exists to realize software for different purposes. Companies often create variants of their existing software by copying and modifying them to changed requirements. While these so-called clone-and-own approaches allow to save money in short-term, they expose the company to severe risks regarding long-term evolution and product quality. The main reason is the high manual maintenance effort which is needed due to the unknown relations between variants. In this paper, we introduce a model-based approach to identify variability information for OOP code, allowing companies to better understand and manage variability between their variants. This information allows to improve maintenance of the variants and to transition from single variant development to more elaborate reuse strategies such as software product lines. We demonstrate the applicability of our approach by means of a case study analyzing variants generated from an existing software product line and comparing our findings to the managed reuse strategy.}
    }

South Africa 2017

Lioness
Lioness

Venue: Workshop on Advances in Knowledge Extraction and Re-engineering of Software (WAKERS), Stellenbosch, South Africa

Comment: The supervisor of my PhD thesis is working together with colleagues from Stellenbosch University on different research topics (e.g., correctness-by-construction). During her sabbatical, she came up with the idea for the workshop and I was invited to give a presentation on my research on reverse-engineering variability. The linked publication is a journal publication in the special issue of this workshop and presents the results of my collaboration with colleagues from University of Technology in Eindhoven.

Photography: When discussing details of my visit, we came up with the idea to take the opportunity and to combine work with a visit to Kruger National Park. Thus, on the way over, I made a stopover in Johannesburg and we rented a car together with two other colleagues from Germany and Italy. The road trip to Kruger National Park and the actual safari are among the top ten of best experiences, which I had so far. During our visit, I was able to take a lot of nice wildlife pictures and we were lucky to see the big five of wildlife (i.e., rhino, elephant, buffalo, lion and leopard). On my way back to Europe, I had to stopover in Eindhoven to present another paper. As a detour via Germany would not have made sense (I would have stayed only for two nights in Germany), I was also able to stay a bit longer in Stellenbosch and the Cape region after the workshop.

Link to the Photos of Kruger National Park

Link to the Photos of Stellenbosch & Cape Region

Eindhoven 2017

Venue: International Workshop on Variability Modeling in Software-intensive Systems (VaMoS), Eindhoven, The Netherlands

Comment: This visit to Eindhoven was only focused on presenting my paper. However, the workshop reception was in the Philips Museum and the workshop dinner was in one Michelin-star Restaurant Wiesen. Thus, the overall visit to Eindhoven was not only focused on work, but we had the chance to learn more about the history of Philips and eat very exquisite food.

Photography: This was one of the few business trips, where I did not have the chance to take pictures, although, I had the camera with me.

  • [DOI] D. Wille, T. Runge, C. Seidl, and S. Schulze, “Extractive Software Product Line Engineering Using Model-Based Delta Module Generation,” in Proc. of the Intl. Workshop on Variability Modeling in Software-intensive Systems (VaMoS), 2017, p. 36–43.
    [Bibtex] [Publisher Page] [Abstract]

    To satisfy demand for customized products, companies commonly apply so-called clone-and-own strategies by copying functionality from existing products and modifying it to create product variants that have to be developed, maintained, and evolved in isolation. In previous work, we introduced a variability mining technique to identify variability information (commonalities and differences) in block-based model variants (e.g., MATLAB/Simulink models), which can be used to guide manual transition from clone-and-own to managed reuse of a software product line (SPL). In this paper, we present a procedure that uses the extracted variability information to generate a transformational delta-oriented SPL fully automatically. We generate a delta language specifically tailored to transforming models in the analyzed modeling language and utilize it to generate delta modules expressing variation of the SPL’s implementation artifacts. The procedure seamlessly integrates with our variability mining technique and allows to fully adopt a managed reuse strategy (i.e., generation of products from a single code base) without manual overhead. We show the feasibility of the procedure by applying it to state chart and MATLAB/Simulink model variants from two industrial case studies.

    @inproceedings{WRS+17,
    author = {Wille, David and Runge, Tobias and Seidl, Christoph and Schulze, Sandro},
    title = {{Extractive Software Product Line Engineering Using Model-Based Delta Module Generation}},
    booktitle = {{Proc. of the Intl. Workshop on Variability Modeling in Software-intensive Systems (VaMoS)}},
    year = {2017},
    doi = {https://dx.doi.org/10.1145/3023956.3023957},
    pages = {36--43},
    publisher = {ACM},
    abstract = {To satisfy demand for customized products, companies commonly apply so-called clone-and-own strategies by copying functionality from existing products and modifying it to create product variants that have to be developed, maintained, and evolved in isolation. In previous work, we introduced a variability mining technique to identify variability information (commonalities and differences) in block-based model variants (e.g., MATLAB/Simulink models), which can be used to guide manual transition from clone-and-own to managed reuse of a software product line (SPL). In this paper, we present a procedure that uses the extracted variability information to generate a transformational delta-oriented SPL fully automatically. We generate a delta language specifically tailored to transforming models in the analyzed modeling language and utilize it to generate delta modules expressing variation of the SPL's implementation artifacts. The procedure seamlessly integrates with our variability mining technique and allows to fully adopt a managed reuse strategy (i.e., generation of products from a single code base) without manual overhead. We show the feasibility of the procedure by applying it to state chart and MATLAB/Simulink model variants from two industrial case studies.}
    }

Kamiyamaguchi 2017

Mount Fuji
Mount Fuji

Venue: National Institute of Informatics Japan (NII) Shonan School: “Mining Software Repositories: Accomplishments, Challenges and Future Trends” at the Shonan Village, Kamiyamaguchi, Japan

Comment: Although my research is not directly related with this area of work, I was lucky to get accepted to the No.095 Shonan Meeting organized by National Institute of Informatics Japan (NII). The Shonan Meetings have a similar focus as the (at least in academic computer science) famous Dagstuhl Seminars. The idea is to bring researchers from specific areas together for informal meetings to talk about future research directions and to exchange new ideas. This particular meeting was organized as a Shonan School to teach young (PhD) students about mining software repositories (e.g., to analyze the impact of changes on the software quality) by giving lectures and hands-on sessions.

Photography: After the Shonan School, I stayed another week in Tokyo for sightseeing and enjoying the nice Japanese cuisine. Of course, a had my camera along to take pictures. One of the highlights was the visite to the tuna auctions at Tsukiji fish market.

Link to the Photos of Tokyo

Sevilla 2017

Venue: International Systems and Software Product Line Conference (SPLC), Sevilla, Spain

Comment: Although I did not actually visit this conference, I listed it for the sake of completeness. For this conference I had submitted a paper as first author (and another one as second author), which previously got rejected from another conference. When submitting the paper, I already knew that I would not be able to attend the conference myself, because I already had booked a trip to Japan with my girlfriend. Luckily, one of my colleagues and coauthor of the paper agreed to present it for me. What I did not know was that the paper not only would get accepted, but would also receive an award from HITACHI for the best young research paper. While I would have loved to receive the certificate by myself, I enjoyed the vacation with my girlfriend a lot and, thus, was compensated for the missed opportunity.

  • [DOI] D. Wille, K. Wehling, C. Seidl, M. Pluchator, and I. Schaefer, “Variability Mining of Technical Architectures,” in Proc. of the Intl. Systems and Software Product Line Conference (SPLC), 2017, p. 39–48. HITACHI Young Best Paper Award – Research Track.
    [Bibtex] [Publisher Page] [Abstract]

    Technical architectures (TAs) represent the computing infrastructure of a company with all its hardware and software components. Over the course of time, the number of TAs grows with the companies’ requirements and usually a large variety of TAs has to be maintained. Core challenge is the missing information on relations between the existing variants of TAs, which complicates reuse of solutions across systems. However, identifying these relations is an expensive task as architects have to manually analyze each TA individually. Restructuring the existing TAs poses severe risks as often sufficient information is not available (e.g., due to time constraints). To avoid failures in productive systems and resulting loss of profit, companies continue to create new solutions without restructuring existing ones. This increased variability in TAs represents technical debt. In this paper, we adapt the idea of variability mining from the software product line domain and present an efficient and automatic mining algorithm to identify the common and varying parts of TAs by analyzing a potentially arbitrary number of TAs in parallel. Using the identified variability information, architects are capable of analyzing the relations of TAs, identifying reuse potential, and making well-founded maintenance decisions. We show the feasibility and scalability of our approach by applying it to a real-world industrial case study with large sets of TAs.

    @inproceedings{WWS+17c,
    author = {Wille, David and Wehling, Kenny and Seidl, Christoph and Pluchator, Martin and Schaefer, Ina},
    title = {{Variability Mining of Technical Architectures}},
    booktitle = {{Proc. of the Intl. Systems and Software Product Line Conference (SPLC)}},
    year = {2017},
    doi = {https://dx.doi.org/10.1145/3106195.3106202},
    pages = {39--48},
    publisher = {ACM},
    note = {HITACHI Young Best Paper Award - Research Track},
    abstract = {Technical architectures (TAs) represent the computing infrastructure of a company with all its hardware and software components. Over the course of time, the number of TAs grows with the companies' requirements and usually a large variety of TAs has to be maintained. Core challenge is the missing information on relations between the existing variants of TAs, which complicates reuse of solutions across systems. However, identifying these relations is an expensive task as architects have to manually analyze each TA individually. Restructuring the existing TAs poses severe risks as often sufficient information is not available (e.g., due to time constraints). To avoid failures in productive systems and resulting loss of profit, companies continue to create new solutions without restructuring existing ones. This increased variability in TAs represents technical debt. In this paper, we adapt the idea of variability mining from the software product line domain and present an efficient and automatic mining algorithm to identify the common and varying parts of TAs by analyzing a potentially arbitrary number of TAs in parallel. Using the identified variability information, architects are capable of analyzing the relations of TAs, identifying reuse potential, and making well-founded maintenance decisions. We show the feasibility and scalability of our approach by applying it to a real-world industrial case study with large sets of TAs.}
    }
  • [DOI] A. Schlie, D. Wille, S. Schulze, L. Cleophas, and I. Schaefer, “Detecting Variability in MATLAB/Simulink Models: An Industry-Inspired Technique and Its Evaluation,” in Proc. of the Intl. Systems and Software Product Line Conference (SPLC), 2017, p. 215–224.
    [Bibtex] [Publisher Page] [Abstract]

    Model-based languages such as MATLAB/Simulink play an essential role in the model-driven development of software systems. To comply with new requirements, it is common practice to create new variants by copying existing systems and modifying them. Commonly referred to as clone-and-own, severe problems arise in the long-run when no dedicated variability management is installed. To allow for a documented and structured reuse of systems, their variability information needs to be reverse-engineered. In this paper, we propose an advanced comparison procedure, the Matching Window Technique, and a customizable metric. Both allow us to overcome structural alterations commonly performed during clone-and-own. We analyze related MATLAB/Simulink models and determine, classify and represent their variability information in an understandable way. With our technique, we assist model engineers in maintaining and evolving existing variants. We provide three feasibility studies with real-world models from the automotive domain and show our technique to be fast and precise. Furthermore, we perform semi-structured interviews with domain experts to assess the potential applicability of our technique in practice.

    @inproceedings{SWS+17,
    author = {Schlie, Alexander and Wille, David and Schulze, Sandro and Cleophas, Loek and Schaefer, Ina},
    title = {{Detecting Variability in MATLAB/Simulink Models: An Industry-Inspired Technique and Its Evaluation}},
    booktitle = {{Proc. of the Intl. Systems and Software Product Line Conference (SPLC)}},
    year = {2017},
    doi = {https://dx.doi.org/10.1145/3106195.3106225},
    pages = {215--224},
    publisher = {ACM},
    abstract = {Model-based languages such as MATLAB/Simulink play an essential role in the model-driven development of software systems. To comply with new requirements, it is common practice to create new variants by copying existing systems and modifying them. Commonly referred to as clone-and-own, severe problems arise in the long-run when no dedicated variability management is installed. To allow for a documented and structured reuse of systems, their variability information needs to be reverse-engineered. In this paper, we propose an advanced comparison procedure, the Matching Window Technique, and a customizable metric. Both allow us to overcome structural alterations commonly performed during clone-and-own. We analyze related MATLAB/Simulink models and determine, classify and represent their variability information in an understandable way. With our technique, we assist model engineers in maintaining and evolving existing variants. We provide three feasibility studies with real-world models from the automotive domain and show our technique to be fast and precise. Furthermore, we perform semi-structured interviews with domain experts to assess the potential applicability of our technique in practice.}
    }

Vancouver 2017

Foggy sunrise at Stanley Park
Foggy sunrise at Stanley Park

Venue: International Workshop on Feature-Oriented Software Development (FOSD) at the International Conference on Systems, Programming, Languages and Applications: Software for Humanity (SPLASH), Vancouver, British Columbia, Canada

Comment: Just one week after I returned from my vacation in Japan, I flew to Vancouver to present a paper. Because of the huge time difference from Japan over Germany to Canada’s west coast, it was a very exhausting business trip. Nevertheless, the conference was interesting and afterwards I stayed one extra day to visit the city.

Photography: Due to the huge time difference I was jet lagged a lot and, thus, woke up every night around three a.m. Instead of watching late-night shows and movie reruns, I used the extra time to take pictures of Vancouver during the night and at sunrise.

Link to the Photos

  • [DOI] K. Wehling, D. Wille, C. Seidl, and I. Schaefer, “Automated Recommendations for Reducing Unnecessary Variability of Technology Architectures,” in Proc. of the Intl. Workshop on Feature-Oriented Software Development (FOSD), 2017, p. 1–10.
    [Bibtex] [Publisher Page] [Abstract]

    A technology architecture (TA) represents the technical infrastructure of a company and consists of hardware and software components. As the evolution of such TAs is typically uncoordinated, their complexity often grows with a company’s requirements. As a consequence, a variety of redundancies and architectural variants exist, which are not necessary for the architecture’s purpose. This leads to increased costs and higher effort for evolving and maintaining the entire IT landscape. To alleviate these problems, unnecessary variability has to be identified and reduced. As a manual approach requires high effort and is not feasible for largescale analysis, experts face a major challenge. For this purpose, we propose an automated approach, which provides experts with recommendations for restructurings of related TAs in order to reduce unnecessary variability. We show suitability of our approach by expert interviews and an industrial case study with real-world TAs.

    @inproceedings{WWS+17a,
    author = {Wehling, Kenny and Wille, David and Seidl, Christoph and Schaefer, Ina},
    title = {{Automated Recommendations for Reducing Unnecessary Variability of Technology Architectures}},
    booktitle = {{Proc. of the Intl. Workshop on Feature-Oriented Software Development (FOSD)}},
    year = {2017},
    publisher = {ACM},
    pages = {1--10},
    doi = {https://dx.doi.org/10.1145/3141848.3141849},
    abstract = {A technology architecture (TA) represents the technical infrastructure of a company and consists of hardware and software components. As the evolution of such TAs is typically uncoordinated, their complexity often grows with a company’s requirements. As a consequence, a variety of redundancies and architectural variants exist, which are not necessary for the architecture’s purpose. This leads to increased costs and higher effort for evolving and maintaining the entire IT landscape. To alleviate these problems, unnecessary variability has to be identified and reduced. As a manual approach requires high effort and is not feasible for largescale analysis, experts face a major challenge. For this purpose, we propose an automated approach, which provides experts with recommendations for restructurings of related TAs in order to reduce unnecessary variability. We show suitability of our approach by expert interviews and an industrial case study with real-world TAs.}
    }

Toronto 2018

Basketball court with downtown Toronto in the background
Basketball court with downtown Toronto in the background

Venue: International Conference on Computer Science and Software Engineering (CASCON), Toronto, Ontario, Canada

Comment: This time I did not have a talk myself, but one of my colleagues presented our results. However, as our paper was awarded with the best paper award by the IBM Center for Advanced Studies, my supervisor kindly decided that I could visit the conference anyway to network with people and advertise our institute.

Photography: Having visited Toronto in 2010 to stay for one month at a language school, I was really looking forward to this stay to revisit some of the spots from back then. Due to the limited time, I mostly visited spots around downtown Toronto, Toronto Island and the Distillery District.

Link to the Photos

  • [DOI] K. Wehling, D. Wille, C. Seidl, and I. Schaefer, “Reducing Variability of Technically Related Software Systems in Large-scale IT Landscapes,” in Proc. of the Intl. Conference on Computer Science and Software Engineering (CASCON), 2018, p. 224–235. IBM Center for Advanced Studies Best Paper Award.
    [Bibtex] [Publisher Page] [Abstract]

    The number of software systems in a company typically grows with the business requirements. Therefore, IT landscapes in large companies can consist of hundreds or thousands of different software systems. As the evolution of such large-scale landscapes is often uncoordinated, they commonly comprise different groups of related software systems using a common core technology (e.g., Java Web-Application) implemented by a variety of architectural components (e.g., different application servers or databases). This leads to increased costs and higher effort for maintaining and evolving these software systems and the entire IT landscape. To alleviate these problems, the variability of such technically related software systems has to be reduced. For this purpose, experts have to assess and evaluate restructuring potentials in order to take appropriate restructuring decisions. As a manual analysis requires high effort and is not feasible for large-scale IT landscapes, experts face a major challenge. To overcome this challenge, we introduce a novel approach to automatically support experts in taking reasonable restructuring decisions. By providing automated methods for assessing, evaluating and simulating restructuring potentials, experts are capable of reducing the variability of related software systems in large-scale IT landscapes. We show suitability of our approach by expert interviews and an industrial case study with architectures of real-world software systems.

    @inproceedings{WWS+18,
    author = {Wehling, Kenny and Wille, David and Seidl, Christoph and Schaefer, Ina},
    title = {{Reducing Variability of Technically Related Software Systems in Large-scale IT Landscapes}},
    booktitle = {{Proc. of the Intl. Conference on Computer Science and Software Engineering (CASCON)}},
    year = {2018},
    pages = {224--235},
    publisher = {IBM Corporation},
    note = {IBM Center for Advanced Studies Best Paper Award},
    weblink = {https://dl.acm.org/citation.cfm?id=3291291.3291314},
    abstract = {The number of software systems in a company typically grows with the business requirements. Therefore, IT landscapes in large companies can consist of hundreds or thousands of different software systems. As the evolution of such large-scale landscapes is often uncoordinated, they commonly comprise different groups of related software systems using a common core technology (e.g., Java Web-Application) implemented by a variety of architectural components (e.g., different application servers or databases). This leads to increased costs and higher effort for maintaining and evolving these software systems and the entire IT landscape. To alleviate these problems, the variability of such technically related software systems has to be reduced. For this purpose, experts have to assess and evaluate restructuring potentials in order to take appropriate restructuring decisions. As a manual analysis requires high effort and is not feasible for large-scale IT landscapes, experts face a major challenge. To overcome this challenge, we introduce a novel approach to automatically support experts in taking reasonable restructuring decisions. By providing automated methods for assessing, evaluating and simulating restructuring potentials, experts are capable of reducing the variability of related software systems in large-scale IT landscapes. We show suitability of our approach by expert interviews and an industrial case study with architectures of real-world software systems.}
    }