*** Please note updated submission deadline. And please distribute to other relevant lists ***
*** Deadline for submission is 8th of June ****
We are pleased to confirm Eric Verhulst as an invited keynote for CPA 2015.
Title lecture: Occam’s rule applied: Separation of Concerns as a key to Trustworthy Systems Engineering for Complex Systems.
Keep it simple but not too simple means that a complex solution is really a problem that's not very well understood. In formal methods this is reflected not only in the size of the state space, but also in the dependencies between these states. This is the main reason why Formal Modelling is not delivering as expected: the state space explosion would require an infinite amount of resources. If an automated tool can’t handle the state space, how can we expect engineers to do so? This is where CSP comes in, it divides the state space in small manageable chunks, making it easier to reason about the behaviour. There are however a few pre-conditions for this to work: one must take a step back, dividing the complex state space before conquering it, hence thinking about functionalities and how they are related before thinking about the punctual states in space and time.
Extrapolating the CSP abstract process algebra lead to a generic concept of describing systems as a set of Interacting Entities, whereby the Interactions are seen as first class citizens, at the same level as the Entities, decoupling the Entities’ states by explicit information exchanges. We enter hereby the domain of modelling. One major issue with modelling approaches is that while we need different, complementary models to develop a real system, they often have different semantics, if properly defined at all. By being able to hide the internal semantics, one can focus on the interactions and use these as standardised interfaces.
It is clear that for this to work in the software domain, the natural programming model should be concurrent and execute on hardware that is compatible with it, a design feature of the transputer which hasn’t been matched since. This opens the door to multi-domain modelling, whereby e.g parts of the system are continuous and other parts are discrete (as in executing a clocked logic). This gives us an interesting new domain of hybrid logic, a topic we want to explore further in the workshop.
(note: the lecture will be guided by my own personal journey, starting with a spreadsheet to program a parallel machine, covering Peter’s courses in occam and the formal development of our distributed RTOS).
Workshop: dealing with (real)-time in real-world hybrid systems.
One of the issues that has been bothering embedded systems engineers is how to deal with time. Some approaches have attempted to make time part of the modelling language, other approaches turn it in a partial order of events, while most programmers ignore it completely equating QoS with real-time (most of the time but not guaranteed). While in the discrete domain, time is considered to be progressing as a number of clock cycles, in the continuous domain time has an infinitesimal granularity. If we now want to proof the correctness of a hybrid system, people traditionally use time dependent partial ordinary differential equations in the continuous domain and model checkers or provers for the discrete domain. How can we combine the two? From the lecture we remember to separate the concerns. Hence we need time-independent models that when executed on a given platform or in a given system context result in specific time properties (like meeting a deadline or stability). In the discrete domain this can be achieved by using priority as a scheduling parameter. In the continuous domain, engineers routinely transform the model into the frequency domain to prove desired properties using Nyquist or Laplace. The workshop will look for answers on how such hybrid models can be formally verified (as opposed to simulation and testing only).
Second keynote speaker to be confirmed.
| Communicating Process Architectures (CPA) 2015 |
| The 37th. WoTUG Conference on Concurrent and Parallel Systems |
| Sunday (evening) 23rd. - Wednesday (lunch) 26th. August 2015 |
| Host institute: School of Computing, University of Kent |
This is the third *Call for Papers* for CPA 2015. Original papers on concurrency in computer systems are sought presenting novel, interesting
and useful work. Areas relevant for CPA include theory and practice,
software and hardware, languages, tools, design methods, verification, education, application and more.
NEW in this call:
* we are pleased to announce Eric Verhulst, CEO/CTO of Altreonic, as one
of the Keynote speakers at CPA 2015. Eric led the development of the
Virtuoso multi-board RTOS, used in the ESA's Rosetta space mission to
comet 67P/Churyumov-Gerasimenko. Virtuoso (along with Altreonic's new
generation VirtuosoNext, supporting fine-grained task parallellism)
has its roots in principles learnt from CSP, the Transputer and occam.
* we have added a call for proposals for mini-workshops (see below for
the specific URL). These were introduced last year (CPA 2014) with
the purpose of learning about, debating and solving (or, at least,
sizing and starting to solve) interesting problems relevant to the
themes of CPA - details are on the Programme page for CPA 2014 (see
URL below). Last year's workshops explored a great amount of ground
and real solutions emerged.
* we have revised the deadlines for submission of papers, allowing
everyone more time in this busy exam period.
* the registration fee (£275), accommodation costs (£39.50 per night)
and student bursaries (up to £200) are announced.
Important dates (revised):
Paper submission: 8th. June, 2015
Notification of acceptance: 6th. July, 2015
Final revised CRC due: 27th. July, 2015
Conference: 23rd. (Sunday evening)
- 26th. (Wednesday lunch) August 2015
For full details about CPA 2015, please see the on-line pages at:
http://www.wotug.org/cpa2015/ (home page)
http://www.wotug.org/cpa2015/call.shtml (full call for papers)
http://www.wotug.org/cpa2015/authors.shtml (author information)
http://www.wotug.org/cpa2015/workshops.shtml (call for workshops)
http://www.wotug.org/cpa2015/fringe.shtml (fringe programme)
For a glimpse of the structure, papers, workshops and fringe programme at CPA, please refer to the Programme page from last year's conference at Oxford:
CPA is an open-access conference: accepted papers will be published by Open Channel Publishing Ltd. (http://openchannelpublishing.com/)
in the CPA 2015 Proceedings, and made freely available from the WoTUG papers archive. All submissions will be refereed by an international panel of academic and industrial reviewers, with extensive feedback given to authors. Accepted papers are subject to a strong editing process to ensure that matters raised by the reviewers are resolved.
Authors retain copyright on their papers, shared with the publishers.
This means that authors have the right to reuse material from these papers in future publications (e.g. in extended revisions for journals).
CPA runs in a single track over two days, with space for approximately 25 half-hour presentations. In addition, two evening Fringe sessions provide a forum for presenting and discussing new ideas and/or work in progress.
The registration fee (£275) covers:
* attendance at all conference, workshop and fringe sessions;
* coffee/tea breaks, lunches and evening meals, including
the conference dinner;
* one copy of the Proceedings.
En-suite accommodation and breakfasts (£39.50 per night) at Keynes College within the University will be bookable separately. Keynes will be the location for all conference presentations and the evening fringe events.
A limited number of bursaries will be available to support students (i.e. anyone registered for a degree and not in receipt of a full-time
salary) attending the conference. These will be worth between £100 and £200 off the registration fee. Please see the Registration page (see above for URL) for details.
Thank you for reading this Call. Please forward to colleagues who might like to know about CPA 2015. Please contact us directly if you need any further information.
Dr Kevin Chalmers and Dr Jan “Matt” Pedersen, Chairs of Editorial Board CPA 2015
Professor Peter Welch, Chair Communicating Process Architecture Programme Board, Local Chair CPA 2015