This paper investigates a simple, constructive search strategy: an incomplete version of Ginsberg's Dynamic Backtracking which records no information during search, and randomly selects variables for backtracking. Combining this with forward checking and dynamic variable ordering heuristics we obtain algorithms for constraint satisfaction problems, and by adding branch-and-bound we obtain optim...

‎in this paper, using the idea of convexificators, we study boundedness and nonemptiness of lagrange multipliers satisfying the first order necessary conditions. we consider a class of nons- mooth fractional programming problems with equality, inequality constraints and an arbitrary set constraint. within this context, define generalized mangasarian-fromovitz constraint qualification and show t...

Based on experiences with the ORBIS Dienstplan-system [Mey97] — a nurse rostering system that is currently used in about 30 German hospitals — this paper describes how to use constraint processing for automatic rostering. In practice, nurse rostering problems have many varying parameters: Working time accounts, demands on crew attendance, set of used shifts, working time models, etc. Hence, ros...

Based on experiences with the ORBIS Dienstplan-system [12] – a nurse rostering system that is currently used in about 60 German hospitals – this paper describes how to use constraint processing for automatic rostering. In practice, nurse rostering problems have many varying parameters: Working time accounts, demands on crew attendance, set of used shifts, working time models, etc. Hence, roster...

In this paper, the problem of stability, recursive feasibility and convergence conditions stochastic model predictive control for linear discrete-time systems affected by a large class correlated disturbances is addressed. A that guarantees convergence, average cost bound chance constraint satisfaction developed. The results rely on computation probabilistic reachable invariant sets using notio...

Intuitively, if we can prove that a program terminates, we expect some conclusion regarding its complexity. But the passage from termination proofs to complexity bounds is not always clear. In this work we consider Monotonicity Constraint Transition Systems, a program abstraction where termination is decidable (based on the size-change termination principle). We show that these programs also ha...

The ability to represent cross-serial dependencies is one of the central features of Tree Adjoining Grammar (TAG). The class of dependency structures representable by lexicalized TAG derivations can be captured by two graph-theoretic properties: a bound on the gap degree of the structures, and a constraint called well-nestedness. In this paper, we compare formalisms from two strands of extensio...

Hybridization of local search and constraint programming techniques for solving Constraint Satisfaction Problems is generally restricted to some kind of master-slave combinations for specific classes of problems. In this paper we propose a theoretical model based on K.R. Apt’s chaotic iterations for hybridization of local search and constraint propagation. Hybrid resolution can be achieved as t...

Constraint programming uses enumeration and search tree pruning to solve combinatorial optimization problems. In order to speed up this solution process, we investigate the use of semidefinite relaxations within constraint programming. In principle, we use the solution of a semidefinite relaxation to guide the traversal of the search tree, using a limited discrepancy search strategy. Furthermor...

As is well known, the frequency allocation problem for mobile telephone networks can be approximated by a graph coloring problem where vertices model transmitters, colors model frequencies, and an edge corresponds to a pair of transmitters that must not use the same frequency. However, the graph coloring analogy doesn't suuce for modeling real world problems , which involve soft constraints and...