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TUCS Newsletter 1.6.2015

Content of the newsletter

TUCS activities

New courses


Latest publications at TUCS

TUCS activities

TUCS Research Programme activities

Stefan Hallerstede from Aarhus University in Denmark

will give a presentation in B3039 (Algol) at 14:15.

Title: On Anticipating Termination in Event-B

Abstract: Event-B is a formal modelling and verification method that is intended to be practical:

to be used by practitioners (or, engineers) supported by an interactive software tool.

Much of the appearance of Event-B originates in this objective. One of the proof

techniques that is to achieve the objective deals with termination. It permits to prove

termination on lexicographical orders without spelling out the underlying order by

"anticipating" termination of computations. The technique is applicable to sequential

programs but most useful in the verification of concurrent programs.

We demonstrate its usefulness by way of two examples. By way of a third example

we demonstrate that sometimes the technique complicates verification proofs. Worse,

"sometimes" is often, in practice.

Now, in a practical method it appears necessary to decide at some point to adopt

definitively the techniques to be supported. As a consequence, "work arounds" are

developed for cases as the above. This also possible in our situation. A far more

satisfactory solution, however, is to keep the method and tool evolving and avoid

developing "work arounds" whenever possible. We present a simple solution to

the problem and sketch its proof of correctness.

Short bio: Stefan Hallerstede (PhD 2001) is associate professor at Aarhus University in

Denmark since 2011. His research focuses on applied formal methods. This

covers theoretical foundations, tool development and industrial use of mathematical

technique for the description and development of computer systems. In the past, he

has contributed to the development of the Event-B modelling formalism and

co-developed the associated software tool called Rodin. He is currently working on

modelling and verification of sequential and concurrent programs, formal support

for requirements analysis and, more generally, the use of formal techniques in early

stages of (computer) systems engineering.


Title: Small universal Petri nets with inhibitor arcs


Speaker: Dr. Serghei Verlan, University Paris 12, France, http://lacl.univ-paris12.fr/verlan/index.html


Abstract: We investigate the problem of the construction of small-size universal Petri nets with inhibitor arcs. We consider four descriptional complexity parameters: the number of places, transitions, inhibitor arcs, and the maximal degree of a transition. Each of these parameters is aimed to be minimized, a special attention being given to the number of places. We give several constructions that highlight interesting trade-off s.  Using equivalencies between models our results can be translated to vector addition systems with zero check, multiset rewriting with forbidding conditions, or to P systems with inhibitors.

talk: "Finite state transducers and degrees of streams". The talk was given at 12.15 in Publicum, room 150.

Title: The Order-Disorder Interplay

Abstract: Order has many faces and the right strategy to understand it is not to try to define it (weak hope to be successful), but to look for its possible opposites: disorder, randomness, arbitrariness, obscurity, ambiguity, high entropy, high complexity, vagueness, fuzziness, roughness, lack of cohesion, absence of coherency, chaos, imprevisibility, imprecision, approximation, absence of any structure, absence of any rule. The choice among them is contextually dependent. The same situation may fit with some types of disorder, but not with the other types. So, order in some respects may no longer be order in other respects. This fact motivates to refer, at least metaphorically, to chaos in order.


With respect to so many faces of disorder (they could be semiotically distinguished in syntactic, semantic and pragmatic), it is important to mention the fact that today for most of them there are some hypothetical-explanatory mathematical models. Assuming that any such model is a kind of order just in view of its mathematical nature, we infer that most types of disorder are captured by a second, higher order. In other words - and we reach here the essential point - the opposite of order can be perceived only to the extent to which we discover, we identify behind it a new kind of order. "Order in chaos" is not a way to play with words; it reflects the deep nature of things. Similarly, "order in randomness" is perfectly meaningful and a lot of mathematics has been developed to explain it. Order is everywhere; but in some places it is directly or almost directly visible, while in other places it is more or less hidden, sometimes very hidden. The whole human enterprise, be it science.

There is a chapter of Mathematics having the slogan Total disorder does not exist; we can adopt it for the whole human experience, but we have to add: If, however, total disorder exists, it cannot be captured by humans, it is beyond human capacities to approach the world.

Solomon Marcus:

Born March 1, 1925, Bacau, Romania. Diploma(1950) and PhD (1956) in Mathematics, University of Bucharest, Romania, where he became in 1966 Full Professor of Mathematical Analysis and Mathematical Linguistics.  Corresponding Member (1993) and Full Member (2001) of the Romanian Academy. Research activity in Mathematical Analysis, Linguistics, Computer Science, Literary Theory and Analysis, Cultural Anthropology, History and Philosophy of Mathematics; in these fields he published several tens of books in Romanian, English, French, German, Italian, Spanish, Russian, Czech, Hungarian, Serbo-Croatian, Greek and several hundreds of articles in academic journals. He is also active in cultural journals, mainly concerning problems of education. He is recognized as one of the initiators of Mathematical Linguistics and Mathematical Poetics.

Title: Weakly Linear Systems over Max-Plus Algebra

Weakly linear systems (WLS) include not only the systems of the form Ai ⊗ X ≤ X ⊗ Bi , (i ∈ I), where X is an unknown matrix, and I is an arbitrary index set, but also their dual systems X⊗Ai ≤ Bi⊗X, (i ∈ I), and the conjunctions of aforementioned, the systems Ai ⊗ X = X ⊗ Bi , (i ∈ I). WLS emerged recently from the theory of fuzzy automata, where it was shown that all methods for reducing the size of fuzzy automata using fuzzy equivalences and fuzzy preorders are based on solving weakly linear systems of fuzzy relational equations and inequalities. WLS of fuzzy relational equations and inequalities and their application were studied in detail in [1–3]. In this talk we are going to present some of the results regarding WLS over a max-plus algebra: The existence of the greatest solution, and the algorithm for their computation. In case when all finite elements of matrices Ai and Bi ,(i ∈ I) are integers, rationals or particular irrationals and a finite solution exists, the algorithm converges in a finite number of steps. If moreover an arbitrary finite solution is given, a precise bound of convergence is calculated. Otherwise, the algorithm is used to compute approximations to the finite solutions.

Title: “Representation of Scenarios in Finite Two-Dimensional Automata”

Abstract: What type of 2-dimensional patters may be obtained by tiling transitions of finite two-dimensional automata assuming a specific state on each west-north-east-south border?


In this talk we present our results obtained in the last 3 years on this problem. We introduce a formalism using systems of recursive equations built on top of new classes of two-dimensional regular expressions. Then, we propose a research programme for getting structural characterizations for 2-dimensional languages generated by finite two-dimensional automata.

Link to a draft: https://dl.dropboxusercontent.com/u/24589701/StefanescuG_saim-may2015.pdf

Short Bio: Gheorghe Stefanescu is a Professor of Computer Science and the head of the Department of Computer Science at University of Bucharest. He has extensive experience in the formal methods research area. Before joining University of Bucharest in 1995, he spent 15 years as a researcher at the Mathematical Institute of the Romanian Academy. He obtained his PhD at University of Bucharest in 1992. He held several visiting positions at National University of Singapore (3 years), University of Illinois at Urbana-Champaign (1 year), Kyushu University (1 semester). He was awarded the “Grigore Moisil” award of the Romanian Academy in 2000.

TUCS Distinguished Lecture Series

ICT building, Auditorium Beta

Title: "Looking for Computers in the Biological Cell. After Twenty Years"

Host: Ion Petre, Åbo Akademi University and Turku Centre for Computer Science

Abstract: A glimpse on natural computing is carried out, with an autobiographical eye, hence with some details about DNA computing and membrane computing. Besides (types of) problems and results (applications included), some research directions are mentioned which need further efforts. Then the question is raised whether or not "we dream too much" in this area, of bio-inspired computing. Some "impossibility theorems" as those of R. Gandhy and M. Conrad are mentioned.

CV: Gheorghe Paun is a researcher in the Institute of Mathematics of the Romanian Academy, Bucharest. Interested in formal language theory, automata theory, mathematical linguistics, DNA computing, and membrane computing. Long research stages in Germany, Finland, The Netherlands, Canada, Spain, Japan, many visits in universities from other countries (over 100 collaborators from all these countries). Several of his books, written alone or in collaboration, became standard references, e.g., in regulated rewriting, Marcus contextual grammars, grammar systems, DNA computing, membrane computing. This last research area was initiated by him, in 1998, see TUCS Technical Report No. 208, November 1998, www.tucs.fi) and it was soon considered by ISI as a "fast emerging research area of computer science". A comprehensive coverage of the domain is "The Oxford Handbook of Membrane Computing", 2010, edited by Gh. Paun, G. Rozenberg, A. Salomaa.

Gheorghe Paun is a member of the Romanian Academy and of Academia Europaea.

TUCS GP Doctoral Defences

Time: 12 noon

Place: Auditorium Gamma

Time: 12 noon

Place: Auditorium Gamma

Time: 12 noon

Place: Auditorium Armfelt, Arken

Time: 12 noon

Place: Auditorium Beta

New courses

New INFORTE course

SW Technologies and Development for Multi-Device

June 16th – 17th



Professor Cesare Pautasso (University of Lugano, Switzerland)

Professor Juan Manuel Murillo Rodríguez (Universidad de Extremadura, Spain)

Professor Sasu Tarkoma (University of Helsinki, Finland)


Professor Kari Systä (Tampere University of Technology, Finland)

Registration closing date: June 7th

Registration and more information: http://inforte.jyu.fi/events/multi-device_environments


Statistical Methods for Information Systems Research

August 11th–13th, 2015


Registration closing date: August 3rd



Assistant professor Frank Chan, ESSEC Business School, France



This seminar introduces doctoral students to common quantitative statistical methods used in behavioral research in the Information Systems (IS) discipline. It covers the concepts and applications of regression analysis and structural equation modeling (SEM). It provides students with hands-on knowledge of statistical packages, including SPSS/PASW, SmartPLS 2.0.M3, and AMOS.



Cyber Defence

September 21st – 22nd




Adjunct professor Martti Lehto (University of Jyväskylä, Finland)

Professor  Rauno Kuusisto (Finnish Defence Research Agency, Finland)

Associate Professor Rain Ottis (Tallinn University of Technology, Estonia)

Dr. Saara Jantunen (Finnish Defence Research Agency, Finland)


Adjunct professor Martti Lehto (University of Jyväskylä, Finland)


Registration is open: June 1st – September 11th

Registration and more information: http://inforte.jyu.fi/events/cyber-defence


Please, see all detailed programs in INFORTE.fi


Organising of INFORTE.fi courses

Inforte.fi program started operating originally in 2001.During this wholeperiod, the Inforte.fi program has however maintained its standing as a stat- wide program for ICT professionals. It is designed to offer networking and education events to PhD students and professionals working in Finnish companies, polytechnics and public administration. Invited speakers are some of the top international researchers or industry representatives in their field. Inforte.fi’s member university departments will annually organize about 12 workshops and seminars on diverse areas of ICT. The main areas of focus are:

These intensive events can be used as tools for professional education, or as parts of doctoral education. Inforte.fi program delivers certificates of participation, and participants negotiate how these achievements can be included in their studies with their home universities. Inforte.fi events are a way to connect you with other ICT professionals and academics in your field, and build important social networks. Inforte.fi events allow you to update your knowledge and keep on track with the latest scientific and practical knowledge in the ICT field.


Anyone within the member departments can suggest an event. We hope that the event is in line with our main areas of focus. If you have something in mind, contact the Inforte.fi staff and let’s start planning the event!

Inforte.fi’s member university departments are:


The organizer’s payment for organizing an one-day event is 250 € and for a two-day event 500 €. The organizer has to send the Inforte.fi staff his or hers separate tax card or otherwise the Finnish tax authorities will take off 60 % taxes from the payment. Inforte.fi staff will send the organizer a travelling expenses claim form and a bank and personal information form. The travelling expenses claim form needs to be filled only if needed, but the bank and personal information form needs to be filled always. The Inforte.fi office will organize morning coffee with something small to bite to the events, but lunch and afternoon coffee can be bought at participant’s own expense. The organizer can however buy his/her and the speaker’s lunch and afternoon coffee and reimburse those expenses from the Inforte.fi office with the travelling expense claim. Also one feasible dinner with the speaker is allowed to reimburse with the travelling expense claim. However when using the travelling expenses claim, the organizer needs to send all of the original documents and receipts to Inforte.fi office (the address is at the bottom of this document).

The speaker’s payment Inforte.fi pays 120 € / lecturing hour and 60 € / group work hour at most. Lecturing fee is considered salary by Finnish tax office. Because the work is done in Finland, the Finnish tax authorities will automatically take off approximately 35 % taxes. In addition, it is mandatory to take off around 4 % other social security and pension contribution payments from the fee. This will happen automatically - no fee can be paid without these deductions.In addition to travel expenses and accommodation Inforte.fi will pay the speaker daily allowance. Daily allowance is 39 euros or 18 euros per travelling day. Inforte.fi will calculate the daily allowances. Inforte.fi does not cover meal expenses according to receipts. The fee and travel expenses will be paid separately and it may take approximately a month until the payment is on the speaker’s bank account.

The speaker’s travelling and accommodation

Inforte.fi pays for the speakers travelling and accommodation expenses and helps with the arrangements regarding these. If the Inforte.fi event will be merged with other activities in Finland (e.g. seminars) or during the trip, Inforte.fi will pay only a part of the expenses. If the speaker decides to book the trip independently, he/she needs to be in contact with the Inforte.fi staff because only travelling in Economy class will be accepted as expenses. Inforte.fi will book the hotel for the speaker.

Date and other important information about the event

The date of the event has to be agreed on in good time and the Inforte.fi staff has to be informed about it immediately after that. In addition to this the Inforte.fi staff will need the following information as soon as possible:

Remote access

The organizer has to agree with the speaker if participants can be included in the event with remote access. If both sides agree that it can be handled, the organizer has to find out that with what kind of system the speaker is used to and whether the remote access is possible to organize at the event location.

Inforte.fi staff’s contact information:

Annemari Soranto

Project Researcher

Email: office@inforte.fi

Phone: +358 400 247700

Nina Jakonen

Programme planner


Phone: +358 400 247700

Courses on transferable skills at University of Turku



TUCS DAY 25.8.2015

TUCS DAY will be organized in August 25 in Ruissalon Kansanpuisto and Botanical Garden. More information of the event coming soon!

ICALP 2015: Best paper award to Jarkko Kari and Michal Szabados

Jarkko Kari and Michal Szabados won the best paper award in ICALP 2015: Logic, Semantics, Automata and Theory of Programming. The title of their award-wining article is “An Algebraic Geometric Approach to Nivat's Conjecture”.

New Brand better reflects focus - the EIT ICT Labs is going Digital

Dear member of the EIT ICT Labs community,

We are pleased to announce that as of June 1, 2015 the EIT ICT Labs is rebranding as EIT Digital.

The change of the name of our organisation into EIT Digital was approved by our General Assembly on April 30.

EIT Digital is easier to pronounce, better fits our strategy and mission, enables us to build a strong brand and is fully in line with the EIT naming convention for KICs.

The transition process for using EIT Digital as the new name will start on June 1, with the update of our website and social media channels. The launch will be officially announced on our website and press & media platform.

As this transition proceeds, we will reach out to our partners, coached startups and other stakeholders to help adopt the new name whenever necessary (i.e. in contracts, on websites etc.).

See how EIT ICT Labs transforms into EIT Digital here: https://www.youtube.com/watch?v=J-ml5mfrTWo

Computer Science Days, June 4-5

The Annual Finnish Computer Science Days 2015 (in Jyväskylä June 4-5, 2015): Call for Papers


Topic: "ICT for teaching and the research of current issues."

The Organizing Committee invites ICT researchers to submit abstracts (max 3 pages) and to make a presentation, as well as to network with other researchers in the field. Both beginners and more advanced researchers are welcome. Topics include programming, teaching, teaching tools, learning environments (including online and blended learning), K-12 education in information technology, project teaching as well as research methods. The presentations are encouraged to include research proposals for cooperation in networking context.

Abstracts should be delivered to the committee by e-mail tktpaivat-edu.group@korppi.jyu.fi.  Abstracts written in Finnish or English in PDF format should be sent no later than 04/15/2015. The selections will be made by 04/25/2015.

Further info: https://www.jyu.fi/it/konferenssit/tkt_paivat_2015/call_for_papers.

Finnish Bank of Science Terminology

Bank of Finnish computer science terminology


Information about the term bank can be found at:



The whole community’s help to build the terminology for “computer science (in a broad sense)” is of great importance, so read and contribute!

EATCS Bulletin Issue 115 available online

The 114th issue of the EATCS Bulletin, is

now available online at


You can download a pdf with the printed version of the bulletin from


As an EATCS member, you have access to

the members area which contains news and related articles. Young researchers

can find announcements of open positions, news and related articles.

To find out the latest information on EATCS news, activities, conferences,

and much more, find us via social media:

facebook page: https://www.facebook.com/eatcs

google+ : https://plus.google.com/112559236052381533540/posts

youtube channel: http://www.youtube.com/channel/UChc3QOHDEbDdPRErx1uSl6A

twitter: http://twitter.com/eatcs_secretary

Linkedin EATCS group: http://www.linkedin.com/groups?gid=3412855 

EATCS - Young researchers Linkedin group:


Open jobs at University of Turku and Åbo Akademi University

Latest publications at TUCS

Articles in journals (2):

Articles in proceedings (5):

Technical reports (2):