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Constraint Logic Programming: A Survey
"... Constraint Logic Programming (CLP) is a merger of two declarative paradigms: constraint solving and logic programming. Although a relatively new field, CLP has progressed in several quite different directions. In particular, the early fundamental concepts have been adapted to better serve in differe ..."
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Cited by 774 (24 self)
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Constraint Logic Programming (CLP) is a merger of two declarative paradigms: constraint solving and logic programming. Although a relatively new field, CLP has progressed in several quite different directions. In particular, the early fundamental concepts have been adapted to better serve in different areas of applications. In this survey of CLP, a primary goal is to give a systematic description of the major trends in terms of common fundamental concepts. The three main parts cover the theory, implementation issues, and programming for applications.
An Overview of HAL
, 1999
"... Experience using constraint programming to solve reallife problems has shown that finding an efficient solution to the problem often requires experimentation with different constraint solvers or even building a problemspecific constraint solver. HAL is a new constraint logic programming language e ..."
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Cited by 44 (24 self)
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Experience using constraint programming to solve reallife problems has shown that finding an efficient solution to the problem often requires experimentation with different constraint solvers or even building a problemspecific constraint solver. HAL is a new constraint logic programming language expressly designed to facilitate this process. It provides a welldefined solver interface, mutable global variables for implementing a constraint store, and dynamic scheduling which support combining, extending and writing new constraint solvers. Equally importantly, HAL supports semioptional type, mode and determinacy declarations. These allow natural constraint specification by means of type overloading, better compiletime error checking and generation of more efficient runtime code.
Hierarchical ModelBased Diagnosis
 International Journal of ManMachine Studies
, 1991
"... Modelbased reasoning about a system requires an explicit representation of the system's components and their connections. Diagnosing such a system consists of locating those components whose abnormal behavior accounts for the faulty system behavior. In order to increase the efficiency of model ..."
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Cited by 31 (2 self)
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Modelbased reasoning about a system requires an explicit representation of the system's components and their connections. Diagnosing such a system consists of locating those components whose abnormal behavior accounts for the faulty system behavior. In order to increase the efficiency of modelbased diagnosis, we propose a model representation at several levels of detail, and define three refinement (abstraction) operators. We specify formal conditions that have to be satisfied by the hierarchical representation, and emphasize that the multilevel scheme is independent of any particular singlelevel model representation. The hierarchical diagnostic algorithm which we define turns out to be very general. We show that it emulates the bisection method, and can be used for hierarchical constraint satisfaction. We apply the hierarchical modeling principle and diagnostic algorithm to a mediumscale medical problem. The performance of a fourlevel qualitative model of the heart is compared t...
The LyriC Language: Querying Constraint Objects
 In Proceedings of the ACM SIGMOD International Conference on Management of Data
, 1994
"... Proposed in this paper is a novel data model and its language for querying objectoriented databases where objects may hold spatial, temporal or constraint data, conceptually represented by linear equality and inequality constraints. The proposed LyriC language is designed to provide a uniform and f ..."
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Cited by 24 (2 self)
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Proposed in this paper is a novel data model and its language for querying objectoriented databases where objects may hold spatial, temporal or constraint data, conceptually represented by linear equality and inequality constraints. The proposed LyriC language is designed to provide a uniform and flexible framework for diverse application realms such as (1) constraintbased design in two, three, or higherdimensional space, (2) largescale optimization and analysis, based mostly on linear programming techniques, and (3) spatial and geographic databases. LyriC extends flat constraint query languages, especially those for linear constraint databases, to structurally complex objects. The extension is based on the objectoriented paradigm, where constraints are treated as firstclass objects that are organized in classes. The query language is an extension of the language XSQL, and is built around the idea of extended path expressions. Path expressions in a query traverse nested struct...
Constraint and Integer Programming in OPL
 INFORMS Journal on Computing
, 2002
"... In recent years, it has been increasingly recognized that constraint and integer programming have orthogonal and complementary strengths in stating and solving combinatorial optimization applications. In addition, their integration has become an active research topic. The optimization programming la ..."
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Cited by 20 (6 self)
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In recent years, it has been increasingly recognized that constraint and integer programming have orthogonal and complementary strengths in stating and solving combinatorial optimization applications. In addition, their integration has become an active research topic. The optimization programming language opl was a first attempt at integrating these technologies both at the language and at the solver levels. In particular, opl is a modeling language integrating the rich language of constraint programming and the ability to specify search procedures at a high level of abstraction. Its implementation includes both constraint and mathematical programming solvers, as well as some cooperation schemes to make them collaborate on a given problem. The purpose of this paper is to illustrate, using opl, the constraintprogramming approach to combinatorial optimization and the complementary strengths of constraint and integer programming. (Artificial Intelligence; Computer Science; Integer Programming) 1.
Comet in Context
 In PCK50: Proceedings of the Paris C. Kanellakis Memorial Workshop on Principles of Computing & Knowledge
, 2003
"... Combinatorial optimization problems naturally arise in many application areas, including logistics, manufacturing, supplychain management, and resource allocation. They often give rise to complex and intricate programs, because of their inherent computational and software complexity. There is thus a ..."
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Cited by 12 (2 self)
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Combinatorial optimization problems naturally arise in many application areas, including logistics, manufacturing, supplychain management, and resource allocation. They often give rise to complex and intricate programs, because of their inherent computational and software complexity. There is thus a strong need for software tools which would decrease the distance between the specification and the final program. This paper contains a brief description of Comet, an objectoriented language supporting a constraintbased architecture for neighborhood search. It contrasts Comet to constraint programming languages and shows how constraint programming and Comet provides many of the same benefits for constraint satisfaction and neighborhood search respectively. In particular, Comet supports a layered architecture cleanly separating modeling and search aspects of the programs, constraints encapsulating incremental algorithms, and various control abstraction to simplify neighborhood exploration and metaheuristics.
QUADCLP(R): Adding the Power of Quadratic Constraints
 In Proc. CP94 (Principles and Practice of Constraint Programming’94, LNCS 874
, 1994
"... . We report on a new way of handling nonlinear arithmetic constraints and its implementation into the QUADCLP(R) language. Important properties of the problem at hand are a discretization through geometric equivalence classes and decomposition into convex pieces. A case analysis of those equivalen ..."
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Cited by 11 (0 self)
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. We report on a new way of handling nonlinear arithmetic constraints and its implementation into the QUADCLP(R) language. Important properties of the problem at hand are a discretization through geometric equivalence classes and decomposition into convex pieces. A case analysis of those equivalence classes leads to a relaxation (and sometimes recasting) of the original constraints into linear constraints, much easier to handle. Complementing earlier expositions in [18] and [19], the present focus is on applications upholding its worth. 1. Motivation. This paper presents the constraint programming language QUADCLP(R) which offers a powerful novel solving strategy for nonlinear arithmetic constraints under the computing paradigm of logic programming. Emphasis will be given here to the techniques involved in the constraint solver for quadratic constraints over R and to applications making use of this added power. Despite the enormous potential of nonlinear arithmetic constraints in...
IMPACCT: Methodology and Tools for PowerAware Embedded Systems
 Kluwer International Journal, Special Issue on Design Methodologies and Tools for RealTime Embedded Systems
, 2002
"... Poweraware systems are those that must exploit a wide range of power/performance tradeoffs in order to adapt to the power availability and application requirements. They require the integration of many novel power management techniques, ranging from voltage scaling to subsystem shutdown. However, ..."
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Cited by 11 (0 self)
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Poweraware systems are those that must exploit a wide range of power/performance tradeoffs in order to adapt to the power availability and application requirements. They require the integration of many novel power management techniques, ranging from voltage scaling to subsystem shutdown. However, those techniques do not always compose synergistically with each other; in fact, they can combine subtractively and often yield counterintuitive, and sometimes incorrect, results in the context of a complete system. This can become a serious problem as more of these power aware systems are being deployed in mission critical applications.
A Transformation System for CLP with Dynamic Scheduling and CCP
 ACM{SIGPLAN Symposium on Partial Evaluation and Semantic Based Program Manipulation
, 1997
"... In this paper we study unfold/fold transformations for constraint logic programs (CLP) with dynamic scheduling and for concurrent constraint programming (CCP). We define suitable applicability conditions for these transformations which guarantee that the original and the transformed program have the ..."
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Cited by 11 (2 self)
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In this paper we study unfold/fold transformations for constraint logic programs (CLP) with dynamic scheduling and for concurrent constraint programming (CCP). We define suitable applicability conditions for these transformations which guarantee that the original and the transformed program have the same results of successful derivations and the same deadlock free queries. The possible applications of these results are twofold. On one hand we can use the unfold/fold system to optimize CLP and CCP programs while preserving their intended meaning and in particular without the risk of introducing deadlocks. On the other hand, unfold/fold transformations can be used for proving deadlock freeness of a class of queries in a given program: to this aim it is sufficient to apply our transformations and to specialize the resulting program with respect to the given queries in such a way that the obtained program is trivially deadlock free. As shown by several interesting examples, this yields a methodology for proving deadlock freeness which is simple and powerful at the same time.
Solving Mixed and Conditional Constraint Satisfaction Problems
 Constraints
, 2003
"... Constraints are a powerful general paradigm for representing knowledge in intelligent systems. The standard constraint satisfaction paradigm involves variables over a discrete value domain and constraints which restrict the solutions to allowed value combinations. This standard paradigm is inapplica ..."
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Cited by 10 (1 self)
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Constraints are a powerful general paradigm for representing knowledge in intelligent systems. The standard constraint satisfaction paradigm involves variables over a discrete value domain and constraints which restrict the solutions to allowed value combinations. This standard paradigm is inapplicable to problems which are either: (a) mixed, involving both numeric and discrete variables, or (b) conditional? containing variables whose existence depends on the values chosen for other variables, or (c) both, conditional and mixed.