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Rough Sets.

by Zdzis Law Pawlak , George Allen , Unwin , ; W W London , New Norton , York - Int. J. of Information and Computer Sciences , 1982
"... Abstract. This article presents some general remarks on rough sets and their place in general picture of research on vagueness and uncertainty -concepts of utmost interest, for many years, for philosophers, mathematicians, logicians and recently also for computer scientists and engineers particular ..."
Abstract - Cited by 793 (13 self) - Add to MetaCart
particularly those working in such areas as AI, computational intelligence, intelligent systems, cognitive science, data mining and machine learning. Thus this article is intended to present some philosophical observations rather than to consider technical details or applications of rough set theory. Therefore

A Fast Marching Level Set Method for Monotonically Advancing Fronts

by J. A. Sethian - PROC. NAT. ACAD. SCI , 1995
"... We present a fast marching level set method for monotonically advancing fronts, which leads to an extremely fast scheme for solving the Eikonal equation. Level set methods are numerical techniques for computing the position of propagating fronts. They rely on an initial value partial differential eq ..."
Abstract - Cited by 630 (24 self) - Add to MetaCart
describe a particular case of such methods for interfaces whose speed depends only on local position. The technique works by coupling work on entropy conditions for interface motion, the theory of viscosity solutions for Hamilton-Jacobi equations and fast adaptive narrow band level set methods

Sparse coding with an overcomplete basis set: a strategy employed by V1

by Bruno A. Olshausen, David J. Fieldt - Vision Research , 1997
"... The spatial receptive fields of simple cells in mammalian striate cortex have been reasonably well described physiologically and can be characterized as being localized, oriented, and ban@ass, comparable with the basis functions of wavelet transforms. Previously, we have shown that these receptive f ..."
Abstract - Cited by 958 (9 self) - Add to MetaCart
field properties may be accounted for in terms of a strategy for producing a sparse distribution of output activity in response to natural images. Here, in addition to describing this work in a more expansive fashion, we examine the neurobiological implications of sparse coding. Of particular interest

Shape modeling with front propagation: A level set approach

by Ravikanth Malladi, James A. Sethian, Baba C. Vemuri - IEEE TRANSACTIONS ON PATTERN ANALYSIS AND MACHINE INTELLIGENCE , 1995
"... Shape modeling is an important constituent of computer vision as well as computer graphics research. Shape models aid the tasks of object representation and recognition. This paper presents a new approach to shape modeling which retains some of the attractive features of existing methods and over- ..."
Abstract - Cited by 808 (20 self) - Add to MetaCart
along its gradient field with constant speed or a speed that depends on the curvature. It is moved by solving a “Hamilton-Jacob? ’ type equation written for a function in which the interface is a particular level set. A speed term synthesizpd from the image is used to stop the interface in the vicinity

Monetary Policy Shocks: What Have we Learned and to What End?

by Lawrence J. Christiano, Martin Eichenbaum , Charles L. Evans , 1998
"... This paper reviews recent research that grapples with the question: What happens after an exogenous shock to monetary policy? We argue that this question is interesting because it lies at the center of a particular approach to assessing the empirical plausibility of structural economic models that c ..."
Abstract - Cited by 988 (26 self) - Add to MetaCart
that can be used to think about systematic changes in monetary policy institutions and rules. The literature has not yet converged on a particular set of assumptions for identifying the effects of an exogenous shock to monetary policy. Nevertheless, there is considerable agreement about the qualitative

Decentralized Trust Management

by Matt Blaze, Joan Feigenbaum, Jack Lacy - In Proceedings of the 1996 IEEE Symposium on Security and Privacy , 1996
"... We identify the trust management problem as a distinct and important component of security in network services. Aspects of the trust management problem include formulating security policies and security credentials, determining whether particular sets of credentials satisfy the relevant policies, an ..."
Abstract - Cited by 1025 (24 self) - Add to MetaCart
We identify the trust management problem as a distinct and important component of security in network services. Aspects of the trust management problem include formulating security policies and security credentials, determining whether particular sets of credentials satisfy the relevant policies

Construction of abstract state graphs with PVS

by Susanne Graf, Hassen Saidi , 1997
"... We describe in this paper a method based on abstract interpretation which, from a theoretical point of view, is similar to the splitting methods proposed in [DGG93, Dam96] but the weaker abstract transition relation we use, allows us to construct automatically abstract state graphs paying a reasonab ..."
Abstract - Cited by 742 (10 self) - Add to MetaCart
reasonable price. We consider a particular set of abstract states: the set of the monomials on a set of state predicates ' 1 ; :::; ' ` . The successor of an abstract state m for a transition ø of the program is the least monomial satisfied by all successors via ø of concrete states satisfying m

Data cube: A relational aggregation operator generalizing group-by, cross-tab, and sub-totals

by Jim Gray, Adam Bosworth, Andrew Layman, Don Reichart, Hamid Pirahesh , 1996
"... Abstract. Data analysis applications typically aggregate data across many dimensions looking for anomalies or unusual patterns. The SQL aggregate functions and the GROUP BY operator produce zero-dimensional or one-dimensional aggregates. Applications need the N-dimensional generalization of these op ..."
Abstract - Cited by 860 (11 self) - Add to MetaCart
in more complex non-procedural data analysis programs. The cube operator treats each of the N aggregation attributes as a dimension of N-space. The aggregate of a particular set of attribute values is a point in this space. The set of points forms an N-dimensional cube. Super-aggregates are computed

The Magma Algebra System I: The User Language

by Wieb Bosma , John Cannon , Catherine Playoust , 1997
"... In the first of two papers on Magma, a new system for computational algebra, we present the Magma language, outline the design principles and theoretical background, and indicate its scope and use. Particular attention is given to the constructors for structures, maps, and sets. ..."
Abstract - Cited by 1346 (7 self) - Add to MetaCart
In the first of two papers on Magma, a new system for computational algebra, we present the Magma language, outline the design principles and theoretical background, and indicate its scope and use. Particular attention is given to the constructors for structures, maps, and sets.

Testing Equivalences for Processes

by R. De Nicola, M. C. B. Hennessy - Theoretical Computer Science , 1984
"... Abstract. Given a set of processes and a set of tests on these processes we show how to define in a natural way three different eyuitalences on processes. ThesP equivalences are applied to a particular language CCS. We give associated complete proof systems and fully abstract models. These models ha ..."
Abstract - Cited by 526 (37 self) - Add to MetaCart
Abstract. Given a set of processes and a set of tests on these processes we show how to define in a natural way three different eyuitalences on processes. ThesP equivalences are applied to a particular language CCS. We give associated complete proof systems and fully abstract models. These models
Results 1 - 10 of 67,523