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April 25, 2013

CP-2013 CP Solver Workshop: Survey of CP Solvers

An addendum to CP-2013 Workshop "CP Solvers: Modeling, Applications, Integration, and Standardization" (Uppsala, Sweden):
If you an author of a CP solver, we ask you to fill out the following questionnaire (even if you do not plan to submit a presentation or attend the workshop). We plan to present a summary of all CP Solvers at this website before the start of the conference.
And here is the link to the workshop page: Workshop "CP Solvers: Modeling, Applications, Integration, and Standardization".

April 23, 2013

CP-2013 Workshop "CP Solvers: Modeling, Applications, Integration, and Standardization" (Uppsala, Sweden)

I'm very happy to announce the CP-2013 Workshop "CP Solvers: Modeling, Applications, Integration, and Standardization":
To be held at the 19th International Conference on the Principles and Practice of Constraint Programming (http://cp2013.a4cp.org/) in Uppsala, Sweden on Monday September 16, 2013.

Objectives and Scope
The objective of this workshop is to get an industrial overview of currently available CP solvers and their use in real-world applications. The focus of the workshop will be not on implementation but rather on modeling, applications, integration, and standardization. Such an overview will fill a gap in the program of recent CP conferences and will allow CP developers and researchers to share the most recent experience of the actual use of different CP-based tools.

We invite authors of all commercial and open source CP solvers to submit their presentations that should include (but not be limited to) the following topics:

  • Demonstration of modeling facilities using a commonly known problem from the CSPLib
  • Implementation programming languages and why they were selected
  • Covered variable types, global constraints, and search algorithms
  • Integration with LP/MIP/SAT tools
  • Integration with business rules, predictive analytics, and other decision making techniques
  • Real-world use: positive and negative experience
  • Standardization and future plans
If you an author of a CP solver, we ask you to fill out the following questionnaire (even if you do not plan to submit a presentation or attend the workshop). We plan to present a summary of all CP Solvers at this website before the start of the conference.

We also welcome application developers and researchers who use different CP tools and who are willing to share their practical experience.

A special focus will be on CP standardization efforts including:

  • Development of CP APIs for different programming environments
  • CP XML for interchange of constraint satisfaction/optimization problems
  • CP design patterns
  • Libraries of commonly used constraints
  • Collections of constraint satisfaction and optimization problems.

An expert panel discussion will be held at the end of this one-day workshop.

We hope that the workshop will help to improve communication between different CP vendors, between solver developers and their users, and will ultimately encourage a wider use of CP technology as a key component of the modern decision making applications.

Target Audience

  • Developers and users of different CP solvers
  • Business application developers who want to incorporate CP-based tools into their decision support systems
  • CP researchers.

Schedule
[To be defined]

Important Dates

  • Sunday, June 16 Presentation title and abstract submission
  • Tuesday, July 16 Acceptance notification
  • Friday, August 16 Complete presentation submission
  • Monday, September 16 Workshop

Organizing Committee

• Jacob Feldman, OpenRules, Monroe, NJ, USA jacobfeldman@openrules.com
• Helmut Simonis, 4C, Cork, Ireland h.simonis@4c.ucc.ie
• Hakan Kjellerstrand, Independent Researcher, Malmo, Sweden hakank@gmail.com

Submission
All abstracts and presentations must be submitted in PDF format using EasyChair. All accepted presentations will be made publicly available of the workshop’s website. At least one author of any accepted presentation must attend the event. An accepted presentation will be withdrawn if no such participation is secured with the payment of the workshop dues.

Please note that we invite authors of all CP solvers written using any languages to make brief presentations of their tools.

This is exciting, not only for the workshop itself (which is about my favorite areas in CP), but also because I'm a co-organizer (an honourable task). This will be very interesting. I hope to see you there!

April 22, 2013

SweConsNet Workshop 2013 - Second call for presentations and participation

Second call for presentations and participation: The 12th workshop of SweConsNet, the Network for Sweden-based researchers and practitioners of Constraint programming, Hosted at Lund University, Lund, Sweden, May 27th, 2013.
The 12th Workshop of the Network of Sweden-based researchers and practitioners of Constraint programming

SweConsNet is the Network for Sweden-based researchers and practitioners of Constraint programming.

Following the previous successful workshops, we would like to announce the 12th SweConsNet workshop, which will take place in Lund, Sweden on May 27th 2013. The purpose of this workshop is to learn about ongoing research in constraint programming, as well as existing projects and products. We will also discuss the further development of the network, such as a possible widening to other Nordic countries.

The workshop is open to everybody interested in the theory and practice of constraint programming, whether based in Sweden or elsewhere. The scope of the workshop spans all areas of Constraint Programming, and is open to presentations and discussions addressing topics related to both theory and application.

Please forward a link of this page to people who might be interested but are not yet on the SweConsNet mailing list. They can subscribe to it by sending a message to Justin.Pearson [at] it.uu.se.

We hope for your participation, and highly encourage you to submit a proposal for a presentation of your ongoing work, recent results, or of a relevant discussion topic. There are no paper submissions, reviews, or proceedings, hence recent conference/journal papers may also be presented.

To register, please fill your data in the registration form. If you want to propose a presentation, please send also the title and the abstract of your talk. In order to facilitate organization, please notify us of your intention to participate as soon as possible, and at the latest before May 10th, 2013. The workshop does not have a registration fee.

In the program so far

Participants will be presented continously

1. Jean-Noël Monette (Uppsala University): Towards solver-independent propagators

2. Håkan Kjellerstrand: What I (still) like about Constraint Programming

3. Mats Carlsson (SICS), TBD.

4. Christian Schulte (KTH), TBD.

5. Björn Regnell (LTH),A Scala DSL for Constraint-based Requirement Engeineering

6. Mehmet A. Arslan (LTH), Instructions Selection and Scheduling for DSP Kernels on Custom Architectures.
I just registered my own talk: What I (still) like about Constraint Programming. with the Presentation abstract:
This is a presentation about fascinating features in Constraint Programming: those I personally find very appealing and/or unique (e.g. compared to other programming paradigms/systems), especially regarding the modeling aspect.
I guess that many/most of the attendants know these "fascinating features" already, but all might not agree (I hope) that they are as important (or fascinating) as I find them.

April 11, 2013

The MiniZinc Challenge 2013 and other MiniZinc news

Here are some news from the G12 MiniZinc world.

MiniZinc main page: www.minizinc.org

The MiniZinc main page has changed to www.minizinc.org.

MiniZinc challenge

From MiniZinc Challenge 2013:
The aim of the MiniZinc Challenge is to start to compare various constraint solving technology on the same problems sets. The focus is on finite domain propagation solvers. An auxiliary aim is to build up a library of interesting problem models, which can be used to compare solvers and solving technologies.

Entrants to the challenge provide a FlatZinc solver and global constraint definitions specialized for their solver. Each solver is run on 100 MiniZinc model instances. We run the translator mzn2fzn on the MiniZinc model and instance using the provided global constraint definitions to create a FlatZinc file. The FlatZinc file is input to the provided solver. Points are awarded for solving problems, speed of solution, and goodness of solutions (for optimization problems).

Registration opens: Wed, 1 May 2013.
Problem submission deadline: Fri, 14 June 2013.
Initial submission round begins: Mon, 1 July 2013.
Initial submission round ends: Fri, 19 July 2013.
Final submissions: Fri, 2 August 2013.
Announcement of results at CP2013: 17 - 20 September 2013.


For details of the competition see:

http://www.minizinc.org/challenge2013/challenge.html

Note that the scoring system has slightly changed this year, so that solvers that obtain indistiguishable results in quality of solution split the points inversely proportional to the time taken

To register for the challenge please email

mzn-challenge@minizinc.org

Here is the Call for Problem Submission:
The MiniZinc Challenge is an annual solver competition in the Constraint Programming (CP) community held before the International Conference on Principles and Practice of Constraint Programming. The MiniZinc Challenge 2013 is seeking interesting problem sets on which various constraint solving technologies should be compared on this year. Everyone is allowed to submit problems regardless of whether they are an entrant in the challenge.

Important dates and deadlines:

Problem submission open: now
Problem submission deadline: Fri, 14 June 2013

Problem submission

Send an email with the subject line “[MZNC13] benchmark” to mzn-challenge 'at' minizinc.org

There are no restrictions on the kind of problems, but ideally they should be of interesting nature such as practice-related problems and puzzles etc. Problem submissions with real-world instances are welcome warmly. Models for the 2013 challenge can only use integer and Boolean variables.

The problem submitter provides a MiniZinc model of the problem and 20 instances ranging from easy-to-solve to hard-to-solve for an “ordinary” CP system. It is strongly encouraged to make use of the global constraint definitions provided in the MiniZinc 1.6 distribution. Please, follow the links below for submission instructions and requirements.
MiniZinc Challenge 2013
Also see: MiniZinc Challenge Medals 2008-2012

MiniZinc forum

Also just released is The MiniZinc forums with three forums:
  • Beginners: All beginner-level questions about MiniZinc.
  • Users: General discussion about MiniZinc. For beginners' questions please use the dedicated Beginners' Forum.
  • Developers: Discussions about developing the MiniZinc system and solvers that interface with MiniZinc.