Constraint programming can be divided very crudely into modeling and solving. Modeling defines the problem, in terms of variables that can take on different values, subject to restrictions (constraints) on which combinations of variables are allowed. Solving finds values for all the variables that simultaneously satisfy all the constraints. However, the impact of constraint programming has been...

During the last decade, the stringent pressures from environmental and social requirements have spurred an interest in designing a reverse logistics (RL) network. The success of a logistics system may depend on the decisions of the facilities locations and vehicle routings. The location-routing problem (LRP) simultaneously locates the facilities and designs the travel routes for vehicles among ...

This paper presents a constraint programming approach to the Enigma 1225, a mathematical puzzle published in the New Scientist magazine in February 2003. An approach based on Prolog was published recently. In this paper we give a constraint programming perspective on the problem, highlighting the differences between the two methodologies. We show how problem-specific knowledge can be easily inc...

abstract the purpose of this paper is to investigate the factors affecting adoption of agricultural crops insurance among apple growers in semirom and eghlid shahrestans and determining the best model. a survey was conducted using the stratified random sampling. data were collected by questionnaire from 240 adopters and 157 non – adopters. the results showed that adopters of insurance are more ...

We propose a model checking scheme for a semantically complete fragment of CTL by combining techniques from constraint logic programming, a restricted form of constructive negation and tabled resolution. Our approach is symbolic in that it encodes and manipulates sets of states using constraints; it supports local model checking using goal-directed computation enhanced by tabulation. The framew...

This research exploits the view of constraint programming as computation in a logical system, namely constraint logic. The basic ingredients of constraint logic are: constraint models for the semantics (they form a comma-category over a fixed model of “built-ins”), generalized polynomials in the rôle of basic syntactic ingredient, and a constraint satisfaction relation between semantics and syn...

The problem of synchronization of multimedia objects is addressed within the framework of concurrent constraint programming by presenting an analysis on how the timed version of concurrent constraint programming can be used to model the temporal behaviour and relationships of multimedia objects. The implementation of a non-trivial multimedia application is presented, using the techniques discus...

We study threshold properties of random constraint satisfaction problems under a probabilistic model due to Molloy [11]. We give a sufficient condition for the existence of a sharp threshold that leads (for boolean constraints) to a necessary and sufficient for the existence of a sharp threshold in the case where constraint templates are applied with equal probability, solving thus an open prob...

Traditional vehicle routing problems implicitly assume only one crew operates a vehicle for the entirety of its journey. However, this assumption is violated in many applications arising in humanitarian and military logistics. This paper considers a Joint Vehicle and Crew Routing and Scheduling Problem, in which crews are able to interchange vehicles, resulting in space and time interdependenci...

We propose a flexible model and several integer linear programming and constraint programming formulations for integrated employee timetabling and production scheduling problems. A hybrid constraint and linear programming exact method is designed to solve a basic integrated employee timetabling and job-shop scheduling problem for lexicographic minimization of makespan and labor costs. Prelimina...