Results 261 to 270 of about 4,720,579 (297)

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
openaire   +1 more source

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
openaire   +2 more sources

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.
openaire   +2 more sources

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
openaire   +3 more sources

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 ...
openaire   +1 more source

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.
openaire   +1 more source

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.
openaire   +1 more source

Approximation of Metric Spaces by Partial Metric Spaces

Applied Categorical Structures, 1999
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
openaire   +3 more sources

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.
openaire   +2 more sources

The Connectivity of the Covering Approximation Space

2015
As a covering approximation space, its connectivity directly reflects a relationship, which plays an important role in data mining, among elements on the universe. In this paper, we study the connectivity of a covering approximation space and give its connected component. Especially, we give three methods to judge whether a covering approximation space
Duixia Ma, William Zhu 0001
openaire   +1 more source