" /> My Constraint Programming Blog: May 2013 Archives

« April 2013 | Main | June 2013 »

May 12, 2013

Program for SweConsNet Workshop 2013 (Lund, 27 May 2013)

Here is the program for 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 for partcipation in the registration form no later than May 22. The workshop does not have a registration fee.

Program

TimeContent
09.30Registration and coffee
10.00

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

We present an extension to indexicals to describe propagators for global constraints. The resulting language is compiled into actual propagators for different solvers, and is solver-independent. In addition, we show how this high-level description eases the proof of propagator properties, such as correctness and monotonicity. Experimental results show that propagators compiled from their indexical descriptions are sometimes not significantly slower than built-in propagators of Gecode. Therefore, our language can be used for the rapid prototyping of new global constraints

10.40

Mats Carlsson (SICS) (joint work with Nicolas Beldiceanu & Aranud Letort)
Scalable Scheduling Constraints

The topic of this talk is synchronized sweep-based filtering algorithms for resource and precedence constraints that are common in scheduling problems.  We first describe a sweep-based implementation of the time-tabling method for "cumulative". Step by step, we then extend this algorithm to handle colored resources, multiple resources, and precedences.  We also derive from the filtering algorithm a greedy assignment algorithm, which is useful for very large scale problems where normal tree search would run out of memory.

11.20

Mehmet A. Arslan (LTH)
Instruction Selection and Scheduling for DSP Kernels on Custom Architectures

As custom architectures become more and more common for DSP applications, instruction selection and scheduling for such applications and architectures become important topics. In this paper, we explore the effects of defining the problem of finding an optimal instruction selection and scheduling as a constraint satisfaction problem (CSP). We incorporate methods based on sub-graph isomorphism and global constraints designed for scheduling. We experiment using several media applications on a custom architecture, a generic VLIW architecture and a RISC architecture, all three with several cores. Our results show that defining the problem with constraints gives flexibility in modeling, while state-of-the-art constraint solvers enable optimal solutions for large problems, hinting a new method for code generation. 

12.00LUNCH
13.00

Kim-Anh Tran (SICS)
Investigation of Implied Constraints in a Constraint-Based Compiler Back-end

Adding implied constraints addressing register allocation and instruction scheduling to the constraint model of a compiler back-end can be crucial to the performance of the code generator. In the hope of cutting down the search effort, implied constraints are investigated, implemented and evaluated. The talk will cover current findings of a master thesis on a set of implied constraints and give an insight into their actual impact on the code generation problem.

13.40

Håkan Kjellerstrand
What I like about Constraint Programming

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.

14.20

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

Software Requirements Engineering (RE) includes the challenging activities of release planning and prioritization, which both are suitable to be tackled by constraint solving. However, there is a need for integrating the representation of software requirements with the representation of constraints in a way that is easy to use by practitioners. This talk aims to interactively discuss what types of constraints are essential in this domain and present and invite feedback on a prototype tool that provides a Scala-internal DSL for Constraint-based RE, wrapping the JaCoP solver.

15.00Coffee break
15.30

Krzysztof Kuchcinski (LTH) 
Mapping Streaming Application into MPSoc

16.10Workshop closure

May 06, 2013

CP-2013 Workshops

The Workshops for CP-2013 (Uppsala, 16 September 2013) has been published. From the Workshops page:

The following workshops will take place before the main conference on September 16.

WCB13: Constraint Based Methods for Bioinformatics

WCB'13 is the 9-th of a series of consecutive Workshop on Constraint Based Methods for Bioinformatics. The topics of interest are all those concerning bioinformatics and constraints and related techniques.
workshop homepage

TRICS13: Techniques foR Implementing Constraint programming Systems

Constraint programming systems are software systems that support the modeling and solving of problems using constraint programming. Such systems include constraint programming libraries and runtime systems for constraint programming languages. This workshop, the fourth in the series, will focus on implementation issues of such systems.
workshop homepage

CSP-SAT: 3rd International Workshop on the Cross-Fertilization between CSP and SAT

Constraint Satisfaction Problems (CSP’s) and Boolean Satisfiability Problems (SAT) have much in common. However, they also differ in many important aspects, which result in major differences in solution techniques. This workshop is designed as a venue for bridging the gap and for cross-fertilization between the two communities.

CP Solvers: Modeling, Applications, Integration, and Standardization

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.
workshop homepage

Workshop on Optimization for Smart Cities

Policy makers who run the complex network of diverse people, expected services and aging infrastructure are on a constant search for more efficient ways to analyse data, anticipate problems and coordinate resources in their cities. This workshop has the purpose of bringing together scholars and practitioners that work on the solution of problems related to the improvement of the quality of life and the use of resources in cities, to make cities smarter.
workshop homepage

COSpeL: Domain Specific Languages in Combinatorial Optimization

Domain Specific Languages (DSLs) are programming languages or libraries developed to handle specific tasks. The aim of COSpeL is to bring together people interested in the development and use of DSLs in the context of combinatorial optimization.
workshop homepage

ModRef: Constraint Modelling and Reformulation

This workshop covers modelling and reformulation techniques that make constraint programming more accessible and easier to use, widening the use of CP technology.
workshop homepage

As mentioned earlier, I have a special interest in the CP Solvers: Modeling, Applications, Integration, and Standardization Workshop