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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 769 (23 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.
Theory and Practice of Constraint Handling Rules
, 1998
"... Constraint Handling Rules (CHR) are our proposal to allow more flexibility and applicationoriented customization of constraint systems. CHR are a declarative language extension especially designed for writing userdefined constraints. CHR are essentially a committedchoice language consisting of mu ..."
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Cited by 396 (35 self)
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Constraint Handling Rules (CHR) are our proposal to allow more flexibility and applicationoriented customization of constraint systems. CHR are a declarative language extension especially designed for writing userdefined constraints. CHR are essentially a committedchoice language consisting of multiheaded guarded rules that rewrite constraints into simpler ones until they are solved. In this broad survey we aim at covering all aspects of CHR as they currently present themselves. Going from theory to practice, we will define syntax and semantics for CHR, introduce an important decidable property, confluence, of CHR programs and define a tight integration of CHR with constraint logic programming languages. This survey then describes implementations of the language before we review several constraint solvers  both traditional and non standard ones  written in the CHR language. Finally we introduce two innovative applications that benefited from using CHR.
The Exact Computation Paradigm
, 1994
"... We describe a paradigm for numerical computing, based on exact computation. This emerging paradigm has many advantages compared to the standard paradigm which is based on fixedprecision. We first survey the literature on multiprecision number packages, a prerequisite for exact computation. Next ..."
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Cited by 94 (10 self)
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We describe a paradigm for numerical computing, based on exact computation. This emerging paradigm has many advantages compared to the standard paradigm which is based on fixedprecision. We first survey the literature on multiprecision number packages, a prerequisite for exact computation. Next we survey some recent applications of this paradigm. Finally, we outline some basic theory and techniques in this paradigm. 1 This paper will appear as a chapter in the 2nd edition of Computing in Euclidean Geometry, edited by D.Z. Du and F.K. Hwang, published by World Scientific Press, 1994. 1 1 Two Numerical Computing Paradigms Computation has always been intimately associated with numbers: computability theory was early on formulated as a theory of computable numbers, the first computers have been number crunchers and the original massproduced computers were pocket calculators. Although one's first exposure to computers today is likely to be some nonnumerical application, numeri...
A Geometric Constraint Solver
, 1995
"... We report on the development of a twodimensional geometric constraint solver. The solver is a major component of a new generation of CAD systems that we are developing based on a highlevel geometry representation. The solver uses a graphreduction directed algebraic approach, and achieves interact ..."
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Cited by 61 (9 self)
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We report on the development of a twodimensional geometric constraint solver. The solver is a major component of a new generation of CAD systems that we are developing based on a highlevel geometry representation. The solver uses a graphreduction directed algebraic approach, and achieves interactive speed. We describe the architecture of the solver and its basic capabilities. Then, we discuss in detail how to extend the scope of the solver, with special emphasis placed on the theoretical and human factors involved in finding a solution  in an exponentially large search space  so that the solution is appropriate to the application and the way of finding it is intuitive to an untrained user. 1 Introduction Solving a system of geometric constraints is a problem that has been considered by several communities, and using different approaches. For example, the symbolic computation community has considered the general problem, in the Supported in part by ONR contract N0001490J...
Extending Prolog with Constraint Arithmetic on Real Intervals
, 1990
"... Prolog can be extended by a system of constraints on closed intervals to perform declarative relational arithmetic. Imposing constraints on an interval can narrow its range and propagate the narrowing to other intervals related to it by constraint equations or inequalities. Relational interval ar ..."
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Cited by 51 (7 self)
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Prolog can be extended by a system of constraints on closed intervals to perform declarative relational arithmetic. Imposing constraints on an interval can narrow its range and propagate the narrowing to other intervals related to it by constraint equations or inequalities. Relational interval arithmetic can be used to contain #oating point errors and, when combined with Prolog backtracking, to obtain numeric solutions to linear and nonlinear rational constraint satisfaction problems over the reals #e.g. ndegree polynomial equations#. This technique di#ers from other constraint logic programming #CLP# systems like CLP### or PrologIII in that it does not do any symbolic processing. 1
Interactive specification of flexible user interface displays
 ACM Transactions on Information Systems
, 1990
"... One of the problems with conventional UIMSs is that very often there is no graphical way to specify interfaces. This paper describes OPUS, the user interface editor of the Penguims UIMS. This system allows the presentation component of graphical user interfaces to be specified interactively in a gra ..."
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Cited by 42 (4 self)
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One of the problems with conventional UIMSs is that very often there is no graphical way to specify interfaces. This paper describes OPUS, the user interface editor of the Penguims UIMS. This system allows the presentation component of graphical user interfaces to be specified interactively in a graphical notation without explicit programming. The Penguims UIMS supports an underlying model of computation based loosely on spreadsheets. In particular, it supports incremental computations based on a system of equations (oneway constraints) over a set of named values (spreadsheet cells). These equations are used to provide immediate feedback at all levels of the interface. They are used to incrementally determine the position and dynamic appearance of the individual interactor objects that make up the interface. They are also used to connect the presentation directly to underlying application data thereby supporting semantic feedback. The OPUS user interface editor employs a special graphical notation for specifying the presentation component of a user interface. This notation allows the power of the underlying computational model to be expressed simply and quickly. The resulting presentations are very flexible in nature. They can automatically respond to changes in the size and position of display objects and can directly support derivation of their appearance from application data objects.
Geometric constraint solving
 Computing in Euclidean Geometry
, 1995
"... We survey the current state of the art in geometric constraint solving. Both 2D and 3D constraint solving is considered, and different approaches are characterized. ..."
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Cited by 32 (3 self)
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We survey the current state of the art in geometric constraint solving. Both 2D and 3D constraint solving is considered, and different approaches are characterized.
User Interface Specification Using an Enhanced Spreadsheet Model
, 1993
"... This paper describes a new interactive environment for user interface specification which is based on an enhanced spreadsheet model of computation. This environment allows sophisticated graphical user interfaces with dynamic feedback to be implemented with little or no explicit programming. Its goal ..."
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Cited by 27 (0 self)
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This paper describes a new interactive environment for user interface specification which is based on an enhanced spreadsheet model of computation. This environment allows sophisticated graphical user interfaces with dynamic feedback to be implemented with little or no explicit programming. Its goal is to support user interface specification by nonprogramming experts in human factors, visual design, or the application domain. In addition, the system is designed to allow sophisticated endusers to modify and customize their own interfaces. The system is based on a data flow model of computation. This model is presented to the interface designer in the form of a spreadsheet enhanced with new constructs for easier programming and reuse. These constructs include an improved interactive programming environment, a prototypeinstance based inheritance system, support for composition, abstraction, and customization using indirect references, the addition of support for graphical inputs and outputs, and support for the encapsulation of application data structures and routines within system objects.
An Integrated Approach to System Modelling using a Synthesis of Artificial Intelligence, Software Engineering and Simulation Methodologies
 ACM TRANSACTIONS ON MODELING AND COMPUTER SIMULATION
, 1992
"... Traditional computer simulation terminology includes taxonomic divisions with terms such as "discrete event," "continuous," and "process oriented." Even though such terms have become familiar to simulation researchers, the terminology is distinct from other disciplines such as artificial intellig ..."
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Cited by 21 (12 self)
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Traditional computer simulation terminology includes taxonomic divisions with terms such as "discrete event," "continuous," and "process oriented." Even though such terms have become familiar to simulation researchers, the terminology is distinct from other disciplines such as artificial intelligence and software engineering which have similar goals relating specifically to modelling dynamic systems. There is a need to unify terminology among these disciplines so that system modelling is formalized in a common framework. We present a perspective that serves to characterize simulation models in terms of their procedural versus declarative orientations since these two orientations are prevalent throughout most modelling disciplines that we have encountered. We used a sample dynamic system (e.g., two jug problem) found in artificial intelligence to highlight the connecting threads in system modelling within each discipline. Moreover, in teaching simulation students using this perspe...