Tuesday, December 01, 2015

Logarithms in the cultural pages of an Italian newspaper

Last Saturday, the cultural pages of a major Italian newspaper featured an article with the title "Arte digitale - la creatività salvata da social e logaritmi" ("Digital art - creativity saved by social networks and logarithms", sic) . The article ends with the following war cry: un "logaritmo vi seppellirà" oppure un "logaritmo vi salverà! " (a logarithm will bury you or a logarithm will save you!).

Well, after all, "logarithm" is an anagram of "algorithm" :-)

Friday, November 27, 2015

Whence Algorithmic Game Theory?

I recently saw the slides for the invited talk delivered by Moshe Vardi at SR 2015, the third International Workshop on Strategic Reasoning, which was held in Oxford in the period 21-22 September 2015. The talk was entitled A Revisionist History of Algorithmic Game Theory and must have stimulated some discussion at the workshop.

Moshe's message was that algorithmic game theory is older than the "official history" would make one believe and that
The most important message, however, is that one should tear down the wall between Vol. A and Vol. B. As readers of this blog may have realized, this is a message to which I wholeheartedly subscribe, perhaps because in the small research community I live in, we have to go to each other's talks to even have an audience at all.

Tuesday, November 17, 2015

Call for Workshops Proposals affiliated with ICALP 2016

Irene Finocchi asked me to distribute the appended call for workshop proposals for ICALP 2016. If you plan to organize a TCS workshop, why not co-locating it with that conference in Rome? The workshop chair is Nicola Galesi.

Call for Workshops Proposals affiliated with ICALP 2016
July 11-15, 2016,  Rome, Italy

Workshop proposals are solicited for ICALP 2016. A workshop may relate to any of the three tracks of ICALP, but proposals related to all aspects of theoretical computer science will be considered as well.

ICALP workshops typically feature a number of invited speakers and a number of contributed presentations.  Workshops will be held on the first day of the conference (July 11, 2016) and will have a duration of at most one day.

Workshop proposals should be no longer than two pages and should include:
- title of the workshop;
- person(s) responsible for the workshop (name and email address);
- a short scientific summary and justification of the proposed topic. This should include a discussion of the particular benefits of the topic to the ICALP community;
- the proposed format and agenda;
- procedures for selecting participants and papers;
- expected number of participants.

Proposals should be sent in pdf format to icalp2016@di.uniroma1.it

Important dates
Submission due: December 20, 2015
Notifications: January 10, 2016
Final program due: 15 May 15, 2016

Further information

We provide the following aspects of the workshop organisation:
- registration;
- wireless network, conference rooms, etc. (as for ICALP);
- a link to the web page of the workshop;
- local support and organization.

We do not provide:
- management of any scientific aspects of the workshop program (the workshop organizers are responsible for call for papers, call for participation, notification, program, workshop webpage, publication of workshop proceedings or journal special issues, etc.);
- publicity for the workshop.

Tuesday, November 03, 2015

PC chairs for ICALP 2017

I am happy to inform you that the PC chairs for ICALP 2017, which will be held in Warsaw, Poland, in the period 10-14 July 2017 will be:
The conference chairs will be Mikolaj Bojanczyk and Piotr Sankowski.

On behalf of the EATCS, I thank these colleagues for their willingness to serve.

Sunday, October 25, 2015

27th Nordic Workshop on Programming Theory

The 27th Nordic Workshop on Programming Theory (NWPT 2015) was held at Reykjavik University in the period 21-23 October and was organized by AnnaIngolfsdottir and me in cooperation with our postdocs  Dario Della Monica, Ignacio Fabregas and Alvaro Garcia Perez. It finished on Friday, 23 October,  at around 17:30 after three packed days of scientific presentations.

The workshop had 57 registered participants (50 of which came from abroad, giving yet another indication of the powerful lure of Iceland as a destination for scientific events), and several talks were also attended by some local faculty members and students who were not officially registered for the workshop. All sessions had a good audience, including the very last one.

The workshop was graced by three excellent invited talks and the quality of the contributed presentations was consistently high. It was very pleasing to see many young researchers deliver clear, well prepared and well paced presentations. You can find all the abstracts for the contributed presentations and the slides for nearly all the talks here.

The invited talks were delivered by Rocco De Nicola (IMT Lucca, IT), Marta Kwiatkowska (University of Oxford, UK) and Jiri Srba; (Aalborg University, DK).

Rocco kicked off the workshop with a talk entitled Languages and Models for Collective Adaptive Systems (slides). Collective Adaptive Systems are heterogeneous collections of autonomous task-oriented systems that cooperate on common goals forming a collective system. Such systems consist of massive numbers of components that interact in complex ways amongst themselves and with other systems; they operate in open and non-deterministic environments, dynamically adapting to new requirements, technologies and environmental conditions. Developing such systems poses challenges to the developers such as the sheer number of components, the need to adapt to changing environments and requirements, the emergent behaviour resulting from complex interactions and the uncertainty both at design-time and at run-time. In his talk, Rocco presented the SCEL language developed by his research group for programming collective adaptive systems and its underlying theory.

Jiri delivered the Thursday invited talk on  Techniques and Tools for thefl Analysis of Timed Workflows (slides). According to Wikipedia, a work flow consists of an orchestrated and repeatable pattern of business activity enabled by the systematic organization of resources into processes that transform materials, provide services, or process information. Many such workflows have strong real-time requirements, and their modelling and analysis is a significant challenge.

In his talk, Jiri suggested a workflow model based on timed-arc Petri nets and introduced the foundational problems of soundness and strong (time-bounded) soundness. He addressed the decidability of these problems and showed, among other results, that soundness is decidable for monotonic workflow nets while reachability is undecidable. For general timed-arc workflow nets, soundness and strong soundness become undecidable, though one can design efficient verification algorithms for the practically interesting subclass of bounded nets. Finally, he demonstrated the usability of the theory by presenting case studies dealing with a Brake System Control Unit used in aircraft certification, the MPEG2 encoding algorithm, a blood transfusion workflow and a home automation system for a family house.

The implementation of the algorithms is freely available as a part of the model checker TAPAAL, which I encourage you to try

Last, but not least, Marta delivered  an invited  talk on Computing Reliably with Molecular Walkers (slides). DNA computing is emerging as a versatile technology that promises a vast range of applications, including biosensing, drug delivery and synthetic biology. DNA logic circuits can be achieved in solution using strand displacement reactions, or by decision-making molecular robots, so called 'walkers', that traverse tracks placed on DNA 'origami' tiles. (See, for instance, Luca Cardelli's work.) Similarly to conventional silicon technologies, ensuring fault-free DNA circuit designs is challenging, with the difficulty compounded by the inherent unreliability of the DNA technology and lack of scientific understanding. In her talk, Marta gave an accessible  overview of computational models that capture DNA walker computation and demonstrated the role of quantitative verification and synthesis in ensuring the reliability of such systems. Since stochasticity is an essential component of DNA computing, not surprisingly Marta and her collaborators use the tool PRISM, whose development has been led by Marta herself, in modelling and analysis of molecular programs.

Marta and her co-workers applied quantitative modelling, verification and synthesis to three DNA case studies:
  1. DNA tranducer gate design (with Luca Cardelli),
  2. DNA walker design (with AndrewTurberfield's lab) and
  3. DNA origami dimer (also with AndrewTurberfield's lab).
All were continuous-time Markov chain models, and the first two were modelled analyzed successfully in PRISM. The third proved to be beyond the current capabilities of the tool. If you are interested, you will find papers on those case studies on Marta's publication page.

The workshop also had some local impact. In 
particular, several members of our association of female students in computer science met with Marta Kwiatkowska, Hanne Riis Nielson and 
other female participants to discuss about CS in an informal setting and learn from successful female role models, apart from those at their own institution. We thank these female 
colleagues for their mentoring role.

All in all, it seems to me that NWPT is excellent health and that many workshops, even with published proceedings, can only dream of having the type of support and environment that NWPT boasts.(The NWPT is an informal workshop without published proceedings, but there will be a special issue of a journal to which we will invite some selected contributions.)

The next edition of the workshop will be held in Aalborg. So the workshop will come back to Denmark, where it has not been held since 2009.

Wednesday, October 21, 2015

October 2015 issue of the Bulletin of the EATCS

The 117th issue of the EATCS Bulletin is now available online at http://bulletin.eatcs.org/index.php/beatcs/issue/view/19.

You can download a pdf with the printed version of the Bulletin from this link. 

As is customary for October issues of the Bulletin, this volume includes reports from ICALP 2015 and calls for nomination for EATCS Awards.

The contributions to the BEATCS columns are all interesting as usual. Let me just limit myself to mentioning that the contribution to the Concurrency Column by Ornela Dardha celebrates the prize she received for the Best Italian Dissertation in TCS in 2014. Fans of the Automata Tutor like me will want to read  the piece written by some of the prime movers behind the development of that wonderful tool.

Readers of this post might also be interested in the article Fast Algorithms for Structured Sparsity by Chinmay Hegde, Piotr Indyk and Ludwig Schmidt, which reports on the work on which the ICALP 2015 tutorial by Piotr was based. 

Thanks to Kazuo Iwama, the editor in chief of the BEATCS, the column editors, the colleagues who contributed to this issue of the Bulletin and Efi Chita from the EATCS Secretary Office for their wonderful work.

I hope that you'll enjoy this issue. I think that it is the duty of a scientific association like the EATCS to make its bulletin freely available to the TCS community. However, this would be impossible without the support from the members of the EATCS, whom I thank wholeheartedly.

Tuesday, October 20, 2015

CFP: 15th Scandinavian Symposium and Workshops on Algorithm Theory

This event is taking place at Reykjavik University in June 2016. Consider submitting!


SWAT 2016 - Call for Papers

15th Scandinavian Symposium and Workshops on Algorithm Theory
June 22-24, 2016, Reykjavik, Iceland

Submission deadline: Feb 14, 2016


The symposium, which alternates with the Algorithms and Data Structures
Symposium (WADS), is a forum for researchers in the area of design and
analysis of algorithms and data structures. We invite submissions of
papers presenting original research on algorithms and data structures.
Though we welcome experiments, the theoretical results in the articles
will be the main measure for evaluating their merits. Algorithmic
approaches of interest include, but are not limited to: approximation
algorithms, parametrized algorithms, distributed algorithms, parallel
algorithms, external-memory algorithms, data structures, exponential
time algorithms, online algorithms, randomized algorithms, streaming
algorithms, sub-linear algorithms. The algorithmic problems considered
may be motivated by applications, e.g. in optimization, geometry and
topology, graph analysis, bioinformatics, visualization, string
processing, information retrieval, machine learning, algorithmic game
theory, or mechanism design.


Contributors must submit their papers using the Easychair system.
Submissions should be in LIPIcs format (without font size, margin, or
line spacing changes), and not exceed 12 pages including front page and
references. See
for instructions. Additionally, if full details of proofs do not fit
into the page limit, a clearly marked appendix containing the remaining
details must be included; this appendix will not be regarded as part of
the submission and will be considered only at the discretion of the
program committee. Submissions deviating substantially from this format
risk rejection without consideration of their merits.

Papers submitted for review should represent original, previously
unpublished work. At the time the paper is submitted to the symposium,
and for the entire review period, the paper (or essentially the same
paper) must not be under review by any other conference with published
proceedings or by a scientific journal. However, we encourage authors to
make a preprint of their paper available at a public repository such as
arXiv. At least one author of every accepted paper is expected to register
and present the paper at the symposium. Symposium proceedings will be
published in the "Leibniz International Proceedings in Informatics"
(LIPIcs) series.


Submission deadline: Feb 14, 2016
Author notification: Early April, 2016
Symposium: Feb 17-20, 2016


A prize will be awarded to the author(s) of the best student-authored
paper. A paper is eligible if all of its authors are full-time students
at the time of submission. This must be indicated in the submission


 - Christian Sohler, Technische Universität Dortmund
 - Christian Wulff-Nilsen, University of Copenhagen
 - Dimitris Fotakis, National Technical University of Athens
 - Djamal Belazzougui, University of Helsinki
 - Ely Porat, Bar-Ilan University
 - Fabio Vandin, University of Padova
 - Faith Ellen, University of Toronto
 - Francois Le Gall, University of Tokyo
 - Gerhard Woeginger, Eindhoven University of Technology
 - Gonzalo Navarro, University of Chile
 - Kasper Green Larsen, Aarhus University
 - Marek Karpinski, University of Bonn
 - Marina Papatriantafilou, Chalmers University of Technology and Göteborg University
 - Nodari Sitchinava, University of Hawaii, Manoa
 - Ola Svensson, École Polytechnique Fédérale de Lausanne
 - Petteri Kaski, Aalto University
 - Pinar Heggernes, University of Bergen
 - Rasmus Pagh (chair), IT University of Copenhagen
 - Rob van Stee, University of Leicester
 - Seth Pettie, University of Michigan
 - Stefan Langerman, Université libre de Bruxelles
 - Suresh Venkatasubramanian, University of Utah
 - Therese Biedl, University of Waterloo


 - Christian Konrad, Reykjavík University
 - Magnús M. Halldórsson, Reykjavík University (chair)
 - Páll Melsted, University of Iceland
 - Tigran Tonoyan, Reykjavík University


 - Andrzej Lingas, Lund University
 - Esko Ukkonen, University of Helsinki
 - Jan Arne Telle, University of Bergen
 - Lars Arge, Aarhus University
 - Magnús M. Halldórsson, Reykjavík University


 -http://www.ru.is/~mmh/swat16/  (general information)