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Acyclic Orientation of Drawings
"... Given a set of curves in the plane or a topological graph, we ask for an orientation of the curves or edges which induces an acyclic orientation on the corresponding planar map. Depending on the maximum number of crossings on a curve or an edge, we provide algorithms and hardness proofs for this pro ..."
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Given a set of curves in the plane or a topological graph, we ask for an orientation of the curves or edges which induces an acyclic orientation on the corresponding planar map. Depending on the maximum number of crossings on a curve or an edge, we provide algorithms and hardness proofs
Understanding Line Drawings of Scenes with Shadows
 The Psychology of Computer Vision
, 1975
"... this paper, how can we recognize the identity of Figs. 2.1 and 2.2? Do we use' learning and knowledge to interpret what we see, or do we somehow automatically see the world as stable and independent bf lighting? What portions of scenes can we understand from local features alone, and what confi ..."
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Cited by 436 (0 self)
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configurations require the use of 1obal hypotheses? 19 In this essay I describe a working collection of computer programs which reconstruct threedimensional descriptions from line drawings which are obtained from scenes composed of planefaced objects under various lighting conditions. The system identifies
Recognitionbycomponents: A theory of human image understanding
 Psychological Review
, 1987
"... The perceptual recognition of objects is conceptualized to be a process in which the image of the input is segmented at regions of deep concavity into an arrangement of simple geometric components, such as blocks, cylinders, wedges, and cones. The fundamental assumption of the proposed theory, recog ..."
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Cited by 1272 (23 self)
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by human observers provide empirical support for the theory. Any single object can project an infinity of image configurations to the retina. The orientation of the object to the viewer can vary continuously, each giving rise to a different twodimensional projection. The object can be occluded by other
ACYCLIC ORIENTATIONS OF GRAPHS
, 1973
"... Let G be a finite graph with p vertices and x its chromatic polynomial. A combinatorial interpretation is given to the positive integer (l)px(A), where h is a positive integer, in terms of acyclic orientations of G. In particular, (l)Px(1) is the number of acyclic orientations of G. An applicati ..."
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Cited by 113 (3 self)
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Let G be a finite graph with p vertices and x its chromatic polynomial. A combinatorial interpretation is given to the positive integer (l)px(A), where h is a positive integer, in terms of acyclic orientations of G. In particular, (l)Px(1) is the number of acyclic orientations of G
Preserving and Using Context Information in Interprocess Communication
 ACM Transactions on Computer Systems
, 1989
"... ion Psync is based on a conversation abstraction that provides a shared message space through which a collection of processes exchange messages. The general form of this message space is defined by a directed acyclic graph that preserves the partial order of the exchanged messages. For the purpose ..."
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Cited by 234 (24 self)
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ion Psync is based on a conversation abstraction that provides a shared message space through which a collection of processes exchange messages. The general form of this message space is defined by a directed acyclic graph that preserves the partial order of the exchanged messages. For the purpose
Acyclic and Oriented Chromatic Numbers of Graphs
 J. Graph Theory
, 1997
"... . The oriented chromatic number o ( ~ G) of an oriented graph ~ G = (V; A) is the minimum number of vertices in an oriented graph ~ H for which there exists a homomorphism of ~ G to ~ H . The oriented chromatic number o (G) of an undirected graph G is the maximum of the oriented chromatic n ..."
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Cited by 49 (15 self)
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numbers of all the orientations of G. This paper discusses the relations between the oriented chromatic number and the acyclic chromatic number and some other parameters of a graph. We shall give a lower bound for o (G) in terms of a (G). An upper bound for o (G) in terms of a (G) was given by Raspaud
Finding bimodal and acyclic orientations of mixed planar graphs is NPcomplete
, 2011
"... conducted in the framework of ESF project 10EuroGIGAOP003 GraDR “Graph Draw ..."
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Cited by 2 (1 self)
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conducted in the framework of ESF project 10EuroGIGAOP003 GraDR “Graph Draw
Sinks in Acyclic Orientations of Graphs
, 1999
"... Greene and Zaslavsky proved that the number of acyclic orientations of a graph with a unique sink at a given vertex is, up to sign, the linear coefficient of the chromatic polynomial. We give three new proofs of this result using pure induction, noncommutative symmetric functions, and an algorithmic ..."
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Cited by 16 (1 self)
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Greene and Zaslavsky proved that the number of acyclic orientations of a graph with a unique sink at a given vertex is, up to sign, the linear coefficient of the chromatic polynomial. We give three new proofs of this result using pure induction, noncommutative symmetric functions
Equivalences on acyclic orientations
"... shift, reflection, Tutte polynomial. Abstract The cyclic and dihedral groups can be made to act on the set Acyc(Y) of acyclic orientations of an undirected graph Y, and this gives rise to the equivalence relations ∼κ and ∼δ, respectively. These two actions and their corresponding equivalence classes ..."
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Cited by 2 (2 self)
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shift, reflection, Tutte polynomial. Abstract The cyclic and dihedral groups can be made to act on the set Acyc(Y) of acyclic orientations of an undirected graph Y, and this gives rise to the equivalence relations ∼κ and ∼δ, respectively. These two actions and their corresponding equivalence
Deadlock Prevention by Acyclic Orientations
"... Deadlock prevention for routing messages has a central role in communication networks, since it directly influences the correctness of parallel and distributed systems. In this paper we extend some of the computational results presented in [10] on acyclic orientations for the determination of optima ..."
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Deadlock prevention for routing messages has a central role in communication networks, since it directly influences the correctness of parallel and distributed systems. In this paper we extend some of the computational results presented in [10] on acyclic orientations for the determination
Results 1  10
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262,818