Results 231 to 240 of about 48,526 (265)

Approximate ? spaces

General Relativity and Gravitation, 1977
We show how, for a wide class of asymptotically flat space-times, it is possible to solve the equation for asymptotically shear-free complex null cones (the good-cut equation) to first approximation, and thereby obtain first-order ℋ spaces and associated firstorder asymptotic projective twistor spaces.
E. T. Newman, K. P. Tod
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Calculi of approximation spaces

Fundam. Informaticae, 2006
Summary: This paper considers the problem of how to establish calculi of approximation spaces. Approximation spaces considered in the context of rough sets were introduced by Zdzisław Pawlak more than two decades ago. In general, a calculus of approximation spaces is a system for combining, describing, measuring, reasoning about, and performing ...
Andrzej Skowron, Jaroslaw Stepaniuk, James F. Peters, Roman W. Swiniarski   +3 more
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Space-Bounded Query Approximation

2015
When dealing with large amounts of data, exact query answering is not always feasible. We propose a query approximation method that, given an upper bound on the amount of data that can be used (i.e., for which query evaluation is still feasible), identifies a part C of the data D that (i) fits in the available space budget; and (ii) provides accurate ...
Boris Cule, Floris Geerts, Reuben Ndindi
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The Product Approximation Spaces of Two Covering Approximation Spaces

2016 8th International Conference on Intelligent Human-Machine Systems and Cybernetics (IHMSC), 2016
In this paper, we define a new type of covering approximation space which is called product approximation space of two covering approximation spaces. Based on the important concepts of neighborhood and complementary neighborhood in covering rough set theory, we define four pairs of lower and upper approximation operators on this type of approximation ...
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Approximating Phenomenological Space

2006
Architectural design requires a variety of representations to describe the many expressions a building can be observed through. Commonly, the form and space of a building are represented through the visual abstraction of projective geometry. The medium of geometric representation has become synonymous with architectural space.
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Approximate decidability in euclidean spaces

Mathematical Logic Quarterly, 2003
AbstractWe study concepts of decidability (recursivity) for subsets of Euclidean spaces ℝk within the framework of approximate computability (type two theory of effectivity). A new notion of approximate decidability is proposed and discussed in some detail. It is an effective variant of F.
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Constrained Approximation in Sobolev Spaces

Canadian Journal of Mathematics, 1997
AbstractPositive, copositive, onesided and intertwining (co-onesided) polynomial and spline approximations of functions are considered. Both uniform and pointwise estimates, which are exact in some sense, are obtained.
Hu, Y. K., Kopotun, K. A., Yu, X. M.
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Approximation of Metric Spaces by Partial Metric Spaces

Applied Categorical Structures, 1999
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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Maps between covering approximation spaces and the product space of two covering approximation spaces

International Journal of Approximate Reasoning, 2019
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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Rough Approximation Operators in Covering Approximation Spaces

2006
In this paper, we focus on the study of covering based rough sets in covering approximation spaces. Firstly, two pairs of covering approximation operators are reviewed, their properties are investigated. Secondly, Based on the covering of the covering approximation space, two new coverings of the universe are induced, by which two new pairs of covering
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