Sample records for view graph graph

  1. Graph Algorithms Tours in Graphs

    E-Print Network [OSTI]

    Bar-Noy, Amotz

    terminates only at y. Graph Algorithms 14 #12;Combining the Main and the Secondary Cycles Let C = (x a secondary cycle C starting with y. - Combine the cycles C and C into C. Return the cycle C. Graph AlgorithGraph Algorithms Tours in Graphs Graph Algorithms #12;Special Paths and Cycles in Graphs Euler Path

  2. Multiple Coordinated Views for Network Attack Graphs Steven Noel Michael Jacobs Pramod Kalapa Sushil Jajodia

    E-Print Network [OSTI]

    Noel, Steven

    Multiple Coordinated Views for Network Attack Graphs Steven Noel Michael Jacobs Pramod Kalapa graph-based representations have been developed for modeling combinations of low-level network attacks, relatively little attention has been paid to effective techniques for visualizing such attack graphs

  3. Graphs, Trees Pebbles, Robots

    E-Print Network [OSTI]

    Haas, Ruth

    Graphs, Trees Pebbles, Robots 1 #12;Outline I. Robot Arms. II. Rigid Graphs. III. Characterizations. Applications: (a) Rigid Components. 2 #12;I. Robot arms and the Carpenter's Rule Problem. Can a robot arm

  4. Standards for graph algorithm primitives

    E-Print Network [OSTI]

    Mattson, Tim

    It is our view that the state of the art in constructing a large collection of graph algorithms in terms of linear algebraic operations is mature enough to support the emergence of a standard set of primitive building ...

  5. A heuristic algorithm for graph isomorphism

    E-Print Network [OSTI]

    Torres Navarro, Luz

    1999-01-01T23:59:59.000Z

    polynomial time algorithm O(n?), ISO-MT, that seems' to solve the graph isomorphism decision problem correctly for all classes of graphs. Our algorithm is extremely useful from the practical point of view since counter examples (pairs of graphs for which our...

  6. Hyperbolic Graph Generator

    E-Print Network [OSTI]

    Aldecoa, Rodrigo; Krioukov, Dmitri

    2015-01-01T23:59:59.000Z

    Networks representing many complex systems in nature and society share some common structural properties like heterogeneous degree distributions and strong clustering. Recent research on network geometry has shown that those real networks can be adequately modeled as random geometric graphs in hyperbolic spaces. In this paper, we present a computer program to generate such graphs. Besides real-world-like networks, the program can generate random graphs from other well-known graph ensembles, such as the soft configuration model, random geometric graphs on a circle, or Erd\\H{o}s-R\\'enyi random graphs. The simulations show a good match between the expected values of different network structural properties and the corresponding empirical values measured in generated graphs, confirming the accurate behavior of the program.

  7. Spectral characterizations of sun graphs and broken sun graphs

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Spectral characterizations of sun graphs and broken sun graphs Romain Boulet 10 Dec 2009 Abstract- cyclic graphs. An odd (resp. even) sun is a graph obtained by appending a pendant vertex to each vertex of an odd (resp. even) cycle. A broken sun is a graph obtained by deleting pendant vertices of a sun

  8. Convex Graph Invariants

    E-Print Network [OSTI]

    2010-12-02T23:59:59.000Z

    Dec 2, 2010 ... where A represents the adjacency matrix of a graph, and the maximum is taken over all ...... SDPT3 - a MATLAB software package for.

  9. Graph Generator Survey

    SciTech Connect (OSTI)

    Lothian, Josh [ORNL; Powers, Sarah S [ORNL; Sullivan, Blair D [ORNL; Baker, Matthew B [ORNL; Schrock, Jonathan [ORNL; Poole, Stephen W [ORNL

    2013-12-01T23:59:59.000Z

    The benchmarking effort within the Extreme Scale Systems Center at Oak Ridge National Laboratory seeks to provide High Performance Computing benchmarks and test suites of interest to the DoD sponsor. The work described in this report is a part of the effort focusing on graph generation. A previously developed benchmark, SystemBurn, allowed the emulation of dierent application behavior profiles within a single framework. To complement this effort, similar capabilities are desired for graph-centric problems. This report examines existing synthetic graph generator implementations in preparation for further study on the properties of their generated synthetic graphs.

  10. Graphs associated with semigroups

    E-Print Network [OSTI]

    Baber, Stephen Asa

    2012-06-07T23:59:59.000Z

    the empty graph is not td d t b pl t . A ~b* h 1 g ph G graph having all of its vertices and edges in G. The citations on the following pages follow the style f th ~fdt f th A t M th tt 1 ~S1 t A path is a sequence of distinct vertices, V , V... , . . . , V n' where V and V are adjacent for i 1, 2, . . . , n-l. If there exists a path between two vertices, the pair is said to be connected. A connected ~ra h is a graph in which every pair of vertices is joined by a path. The empty graph...

  11. Graph concatenation for quantum codes

    E-Print Network [OSTI]

    Beigi, Salman

    Graphs are closely related to quantum error-correcting codes: every stabilizer code is locally equivalent to a graph code and every codeword stabilized code can be described by a graph and a classical code. For the ...

  12. Graph anomalies in cyber communications

    SciTech Connect (OSTI)

    Vander Wiel, Scott A [Los Alamos National Laboratory; Storlie, Curtis B [Los Alamos National Laboratory; Sandine, Gary [Los Alamos National Laboratory; Hagberg, Aric A [Los Alamos National Laboratory; Fisk, Michael [Los Alamos National Laboratory

    2011-01-11T23:59:59.000Z

    Enterprises monitor cyber traffic for viruses, intruders and stolen information. Detection methods look for known signatures of malicious traffic or search for anomalies with respect to a nominal reference model. Traditional anomaly detection focuses on aggregate traffic at central nodes or on user-level monitoring. More recently, however, traffic is being viewed more holistically as a dynamic communication graph. Attention to the graph nature of the traffic has expanded the types of anomalies that are being sought. We give an overview of several cyber data streams collected at Los Alamos National Laboratory and discuss current work in modeling the graph dynamics of traffic over the network. We consider global properties and local properties within the communication graph. A method for monitoring relative entropy on multiple correlated properties is discussed in detail.

  13. Querying graphs with data†

    E-Print Network [OSTI]

    Vrgoc, Domagoj

    2014-06-27T23:59:59.000Z

    Graph data is becoming more and more pervasive. Indeed, services such as Social Networks or the Semantic Web can no longer rely on the traditional relational model, as its structure is somewhat too rigid for the applications ...

  14. Fuzzy Mathematics Fuzzy -Sets, -Relations, -Logic, -Graphs,

    E-Print Network [OSTI]

    Rostock, Universität

    Fuzzy Mathematics Fuzzy -Sets, -Relations, -Logic, -Graphs, -Mappings and The Extension Principle . . . . . . . . . . . . . . . . . . 8 2 The Extension Principle 10 3 Fuzzy Graphs 16 4 Fuzzy Logic 19 Back View #12;Section 1: Fuzzy Olaf Wolkenhauer Control Systems Centre UMIST o.wolkenhauer@umist.ac.uk www

  15. Graph Concatenation for Quantum Codes

    E-Print Network [OSTI]

    Salman Beigi; Isaac Chuang; Markus Grassl; Peter Shor; Bei Zeng

    2010-02-03T23:59:59.000Z

    Graphs are closely related to quantum error-correcting codes: every stabilizer code is locally equivalent to a graph code, and every codeword stabilized code can be described by a graph and a classical code. For the construction of good quantum codes of relatively large block length, concatenated quantum codes and their generalizations play an important role. We develop a systematic method for constructing concatenated quantum codes based on "graph concatenation", where graphs representing the inner and outer codes are concatenated via a simple graph operation called "generalized local complementation." Our method applies to both binary and non-binary concatenated quantum codes as well as their generalizations.

  16. Graph dynamics : learning and representation

    E-Print Network [OSTI]

    Ribeiro, Andre Figueiredo

    2006-01-01T23:59:59.000Z

    Graphs are often used in artificial intelligence as means for symbolic knowledge representation. A graph is nothing more than a collection of symbols connected to each other in some fashion. For example, in computer vision ...

  17. Densities in graphs and matroids

    E-Print Network [OSTI]

    Kannan, Lavanya

    2009-05-15T23:59:59.000Z

    |E(H)| |V (H)|?1 ? |E(T)| |V (T)|?1 = 1 for all non-trivial subgraphs of T. In general, a balanced graph G is a graph such that |E(H)| |V (H)| ? |E(G)| |V (G)| and a 1-balanced graph is a graph such that |E(H)| |V (H)|?1 ? |E(G)| |V (G)|?1 for all non...

  18. Temporal Representation in Semantic Graphs

    SciTech Connect (OSTI)

    Levandoski, J J; Abdulla, G M

    2007-08-07T23:59:59.000Z

    A wide range of knowledge discovery and analysis applications, ranging from business to biological, make use of semantic graphs when modeling relationships and concepts. Most of the semantic graphs used in these applications are assumed to be static pieces of information, meaning temporal evolution of concepts and relationships are not taken into account. Guided by the need for more advanced semantic graph queries involving temporal concepts, this paper surveys the existing work involving temporal representations in semantic graphs.

  19. Cliques in graphs

    E-Print Network [OSTI]

    Lo, Allan

    2010-10-12T23:59:59.000Z

    Cliques in Graphs Siu Lun Allan Lo Christís College University of Cambridge A thesis submitted for the degree of Doctor of Philosophy 2010 Declaration This dissertation is the result of my own work and includes nothing which is the outcome of work...

  20. Extremal Graph Numbers of Graphs on Few May 4, 2012

    E-Print Network [OSTI]

    Zeilberger, Doron

    Extremal Graph Numbers of Graphs on Few Vertices John Kim May 4, 2012 1 Introduction Let H this number to be the extremal graph number of H on n vertices, and we denote it by ex(n, H). When H(n, K3) n 2 2 . A precise formula for ex(n, K3) is given by: ex(n, K3) = n 2 n + 1 2 . The extremal

  1. Graph Coarsening for Path Finding in Cybersecurity Graphs

    SciTech Connect (OSTI)

    Hogan, Emilie A.; Johnson, John R.; Halappanavar, Mahantesh

    2013-01-01T23:59:59.000Z

    n the pass-the-hash attack, hackers repeatedly steal password hashes and move through a computer network with the goal of reaching a computer with high level administrative privileges. In this paper we apply graph coarsening in network graphs for the purpose of detecting hackers using this attack or assessing the risk level of the network's current state. We repeatedly take graph minors, which preserve the existence of paths in the graph, and take powers of the adjacency matrix to count the paths. This allows us to detect the existence of paths as well as find paths that have high risk of being used by adversaries.

  2. How to Resum Feynman Graphs

    E-Print Network [OSTI]

    Vincent Rivasseau; Zhituo Wang

    2013-09-24T23:59:59.000Z

    In this paper we reformulate in a simpler way the combinatoric core of constructive quantum field theory We define universal rational combinatoric weights for pairs made of a graph and one of its spanning trees. These weights are nothing but the percentage of Hepp's sectors in which the tree is leading the ultraviolet analysis. We explain how they allow to reshuffle the divergent series formulated in terms of Feynman graphs into convergent series indexed by the trees that these graphs contain. The Feynman graphs to be used are not the ordinary ones but those of the intermediate field representation, and the result of the reshuffling is called the Loop Vertex Expansion.

  3. Graph/Network Visualization Data model: graph structures (relations,

    E-Print Network [OSTI]

    Fang, Shiaofen

    of physics #12;8 The Spring Model Using springs to represent node-node relations. Minimizing energy1 1 Graph/Network Visualization Data model: graph structures (relations, knowledge) and networks hierarchies #12;7 Sugiyama : Building Hierarchy Domain knowledge based. Designing heuristic, e.g. minimizing

  4. Contraction semigroups on metric graphs

    E-Print Network [OSTI]

    Vadim Kostrykin; Jurgen Potthoff; Robert Schrader

    2008-02-26T23:59:59.000Z

    The main objective of the present work is to study contraction semigroups generated by Laplace operators on metric graphs, which are not necessarily self-adjoint. We prove criteria for such semigroups to be continuity and positivity preserving. Also we provide a characterization of generators of Feller semigroups on metric graphs.

  5. Phylogenetic Toric Varieties on Graphs

    E-Print Network [OSTI]

    Buczynska, Weronika J.

    2010-10-12T23:59:59.000Z

    We define the phylogenetic model of a trivalent graph as a generalization of a binary symmetric model of a trivalent phylogenetic tree. If the underlining graph is a tree, the model has a parametrization that can be expressed in terms of the tree...

  6. Contractions of planar graphs in polynomial time?

    E-Print Network [OSTI]

    Dimitrios, Thilikos

    Contractions of planar graphs in polynomial time? Marcin Kami¬īnski??1 , Dani¬®el Paulusma2 that for every graph H, there exists a polyno- mial-time algorithm deciding if a planar graph can be contracted to H. We introduce contractions and topological minors of embedded (plane) graphs and show that a plane

  7. Extremal Graph Problems, Degenerate Extremal Problems,

    E-Print Network [OSTI]

    Simonovits, Miklós

    Extremal Graph Problems, Degenerate Extremal Problems, and Supersaturated Graphs Mikl¬īos Simonovits¬īan-type extremal problem. The graphs attaining the maximum will be called extremal and their family will be denoted and multi- ple edges. In 1940, P. Tur¬īan posed and solved the extremal problem of Kp+1, the complete graph

  8. Virasoro Representations on Fusion Graphs

    E-Print Network [OSTI]

    J. Kellendonk; A. Recknagel

    1992-10-01T23:59:59.000Z

    For any non-unitary model with central charge c(2,q) the path spaces associated to a certain fusion graph are isomorphic to the irreducible Virasoro highest weight modules.

  9. Doing time : inducing temporal graphs

    E-Print Network [OSTI]

    Bramsen, Philip James

    2006-01-01T23:59:59.000Z

    We consider the problem of constructing a directed acyclic graph that encodes temporal relations found in a text. The unit of our analysis is a temporal segment, a fragment of text that maintains temporal coherence. The ...

  10. Managing Attack Graph Complexity Through Visual Hierarchical Aggregation

    E-Print Network [OSTI]

    Noel, Steven

    Managing Attack Graph Complexity Through Visual Hierarchical Aggregation Steven Noel Center a framework for managing network attack graph complexity through interactive visualization, which includes hierarchical aggregation of graph elements. Aggregation collapses non-overlapping subgraphs of the attack graph

  11. Algebraic connectivity and graph robustness.

    SciTech Connect (OSTI)

    Feddema, John Todd; Byrne, Raymond Harry; Abdallah, Chaouki T. (University of New Mexico)

    2009-07-01T23:59:59.000Z

    Recent papers have used Fiedler's definition of algebraic connectivity to show that network robustness, as measured by node-connectivity and edge-connectivity, can be increased by increasing the algebraic connectivity of the network. By the definition of algebraic connectivity, the second smallest eigenvalue of the graph Laplacian is a lower bound on the node-connectivity. In this paper we show that for circular random lattice graphs and mesh graphs algebraic connectivity is a conservative lower bound, and that increases in algebraic connectivity actually correspond to a decrease in node-connectivity. This means that the networks are actually less robust with respect to node-connectivity as the algebraic connectivity increases. However, an increase in algebraic connectivity seems to correlate well with a decrease in the characteristic path length of these networks - which would result in quicker communication through the network. Applications of these results are then discussed for perimeter security.

  12. Graph Analytics for Signature Discovery

    SciTech Connect (OSTI)

    Hogan, Emilie A.; Johnson, John R.; Halappanavar, Mahantesh; Lo, Chaomei

    2013-06-01T23:59:59.000Z

    Within large amounts of seemingly unstructured data it can be diffcult to find signatures of events. In our work we transform unstructured data into a graph representation. By doing this we expose underlying structure in the data and can take advantage of existing graph analytics capabilities, as well as develop new capabilities. Currently we focus on applications in cybersecurity and communication domains. Within cybersecurity we aim to find signatures for perpetrators using the pass-the-hash attack, and in communications we look for emails or phone calls going up or down a chain of command. In both of these areas, and in many others, the signature we look for is a path with certain temporal properties. In this paper we discuss our methodology for finding these temporal paths within large graphs.

  13. Optimization in Geometric Graphs: Complexity and Approximation

    E-Print Network [OSTI]

    Kahruman-Anderoglu, Sera

    2011-02-22T23:59:59.000Z

    We consider several related problems arising in geometric graphs. In particular, we investigate the computational complexity and approximability properties of several optimization problems in unit ball graphs and develop algorithms to find exact...

  14. A discrete curvature on a planar graph

    E-Print Network [OSTI]

    M. Lorente

    2004-12-20T23:59:59.000Z

    Given a planar graph derived from a spherical, euclidean or hyperbolic tessellation, one can define a discrete curvature by combinatorial properties, which after embedding the graph in a compact 2d-manifold, becomes the Gaussian curvature.

  15. Percolation in the Secrecy Graph Amites Sarkar

    E-Print Network [OSTI]

    Sarkar, Amites

    Percolation in the Secrecy Graph Amites Sarkar Martin Haenggi July 8, 2011 Abstract Secrecy graphs. Department of Mathematics, Western Washington University, Bellingham, WA 98225, USA. Email: amites.sarkar

  16. Evan Marshall Trevathan Admissible SC-Graphs

    E-Print Network [OSTI]

    Donnelly, Rob

    Evan Marshall Trevathan Admissible SC-Graphs Page 1 Admissible SC-Graphs Define: ( , )G ( 2)nB n ( 4)nD n ( 6,7,8)nE n 4F 2G 2H 3H #12;Evan Marshall Trevathan Admissible SC-Graphs Page 2 the form of a #12;Evan Marshall Trevathan Admissible SC-Graphs Page 3 "loop", like ,with no other

  17. NLS ground states on graphs

    E-Print Network [OSTI]

    Riccardo Adami; Enrico Serra; Paolo Tilli

    2014-06-16T23:59:59.000Z

    We investigate the existence of ground states for the subcritical NLS energy on metric graphs. In particular, we find out a topological assumption that guarantees the nonexistence of ground states, and give an example in which the assumption is not fulfilled and ground states actually exist. In order to obtain the result, we introduce a new rearrangement technique, adapted to the graph where it applies. Owing to such a technique, the energy level of the rearranged function is improved by conveniently mixing the symmetric and monotone rearrangement procedures.

  18. THE TUKEY ORDER FOR GRAPHS 1. Introduction

    E-Print Network [OSTI]

    Nyikos, Peter J.

    THE TUKEY ORDER FOR GRAPHS 1. Introduction Given a graph G, we let VG stand for the vertex set of G. For graphs G without isolated vertices, the Tukey order can be characterized thus: () G H iff there exist) is called a (generalized) Galois-Tukey connection (abbreviated GT-connection) from R to S if the following

  19. Generalized Graph States Based on Hadamard Matrices

    E-Print Network [OSTI]

    Shawn X Cui; Nengkun Yu; Bei Zeng

    2015-02-25T23:59:59.000Z

    Graph states are widely used in quantum information theory, including entanglement theory, quantum error correction, and one-way quantum computing. Graph states have a nice structure related to a certain graph, which is given by either a stabilizer group or an encoding circuit, both can be directly given by the graph. To generalize graph states, whose stabilizer groups are abelian subgroups of the Pauli group, one approach taken is to study non-abelian stabilizers. In this work, we propose to generalize graph states based on the encoding circuit, which is completely determined by the graph and a Hadamard matrix. We study the entanglement structures of these generalized graph states, and show that they are all maximally mixed locally. We also explore the relationship between the equivalence of Hadamard matrices and local equivalence of the corresponding generalized graph states. This leads to a natural generalization of the Pauli $(X,Z)$ pairs, which characterizes the local symmetries of these generalized graph states. Our approach is also naturally generalized to construct graph quantum codes which are beyond stabilizer codes.

  20. Constrained Graph Optimization: Interdiction and Preservation Problems

    SciTech Connect (OSTI)

    Schild, Aaron V [Los Alamos National Laboratory

    2012-07-30T23:59:59.000Z

    The maximum flow, shortest path, and maximum matching problems are a set of basic graph problems that are critical in theoretical computer science and applications. Constrained graph optimization, a variation of these basic graph problems involving modification of the underlying graph, is equally important but sometimes significantly harder. In particular, one can explore these optimization problems with additional cost constraints. In the preservation case, the optimizer has a budget to preserve vertices or edges of a graph, preventing them from being deleted. The optimizer wants to find the best set of preserved edges/vertices in which the cost constraints are satisfied and the basic graph problems are optimized. For example, in shortest path preservation, the optimizer wants to find a set of edges/vertices within which the shortest path between two predetermined points is smallest. In interdiction problems, one deletes vertices or edges from the graph with a particular cost in order to impede the basic graph problems as much as possible (for example, delete edges/vertices to maximize the shortest path between two predetermined vertices). Applications of preservation problems include optimal road maintenance, power grid maintenance, and job scheduling, while interdiction problems are related to drug trafficking prevention, network stability assessment, and counterterrorism. Computational hardness results are presented, along with heuristic methods for approximating solutions to the matching interdiction problem. Also, efficient algorithms are presented for special cases of graphs, including on planar graphs. The graphs in many of the listed applications are planar, so these algorithms have important practical implications.

  1. Acyclic Coloring of Graphs of Maximum Degree Five: Nine Colors are Enough

    E-Print Network [OSTI]

    Boyer, Edmond

    graphs with "large" girth [BKW99], 1-planar graphs [BKRS01], outerplanar graphs (see for instance [Sop97

  2. EuroComb 2005 DMTCS proc. AE, 2005, 389396 Acyclic Coloring of Graphs of Maximum

    E-Print Network [OSTI]

    Fertin, Guillaume

    for several families F of graphs such as planar graphs [Bor79], planar graphs with "large" girth [BKW99], 1

  3. Acyclic Coloring of Graphs of Maximum Degree Five: Nine Colors are Enough

    E-Print Network [OSTI]

    Fertin, Guillaume

    graphs with ``large'' girth [BKW99], 1­planar graphs [BKRS01], outerplanar graphs (see for instance [Sop

  4. Lamplighter groups, de Bruijn graphs, spider-web graphs and their spectra

    E-Print Network [OSTI]

    Rostislav Grigorchuk; Paul-Henry Leemann; Tatiana Nagnibeda

    2015-02-24T23:59:59.000Z

    We describe the infinite family of spider-web graphs $S_{k,M,N }$, $k \\geq 2$, $M \\geq 1$ and $N \\geq 0$, studied in physical literature as tensor products of well-known de Brujin graphs $B_{k,N}$ and cyclic graphs $C_M$ and show that these graphs are Schreier graphs of the lamplighter groups $L_k = Z/kZ \\wr Z$. This allows us to compute their spectra and to identify the infinite limit of $S_{k,M,N}$, as $N, M \\to\\infty$, with the Cayley graph of the lamplighter group $L_k$.

  5. Nuclear reactor multiphysics via bond graph formalism

    E-Print Network [OSTI]

    Sosnovsky, Eugeny

    2014-01-01T23:59:59.000Z

    This work proposes a simple and effective approach to modeling nuclear reactor multiphysics problems using bond graphs. Conventional multiphysics simulation paradigms normally use operator splitting, which treats the ...

  6. Generating Reports & Graphs in Portfolio Manager

    Broader source: Energy.gov [DOE]

    This presentation, given through the DOE's Technical Assitance Program (TAP), provides information on how to generate reports and graphs in Portfolio Manager.

  7. Hamilton Decompositions of Graphs with Primitive Complements .

    E-Print Network [OSTI]

    OZKAN, SIBEL

    2007-01-01T23:59:59.000Z

    ??A graph G is a pair (V, E) where V is the set of vertices(or nodes) and E is the set of edges connecting theÖ (more)

  8. Graph algorithms in the titan toolkit.

    SciTech Connect (OSTI)

    McLendon, William Clarence, III; Wylie, Brian Neil

    2009-10-01T23:59:59.000Z

    Graph algorithms are a key component in a wide variety of intelligence analysis activities. The Graph-Based Informatics for Non-Proliferation and Counter-Terrorism project addresses the critical need of making these graph algorithms accessible to Sandia analysts in a manner that is both intuitive and effective. Specifically we describe the design and implementation of an open source toolkit for doing graph analysis, informatics, and visualization that provides Sandia with novel analysis capability for non-proliferation and counter-terrorism.

  9. Generation of graph-state streams

    E-Print Network [OSTI]

    Daniel Ballester; Jaeyoon Cho; M. S. Kim

    2010-12-08T23:59:59.000Z

    We propose a protocol to generate a stream of mobile qubits in a graph state through a single stationary parent qubit and discuss two types of its physical implementation, namely, the generation of photonic graph states through an atom-like qubit and those of flying atoms through a cavity-mode photonic qubit. The generated graph states fall into an important class that can hugely reduce the resource requirement of fault-tolerant linear optics quantum computation, which was previously known to be far from realistic. In regard to the flying atoms, we also propose a heralded generation scheme, which allows for high-fidelity graph states even under the photon loss.

  10. Some algorithmic results in graph imbeddings

    E-Print Network [OSTI]

    Joshi, Sanjay

    1990-01-01T23:59:59.000Z

    new technique called double bar amalgamation is developed. The second problem deals with constructing graph imbeddings on a sur- face of genus c (where c is an integer) less than the marimum genus 7, (G) the given graph G. We develop a polynomial... time algorithm that constructs an imbedding of a given upper imbbedable graph G with even Betti number, on an orientable surface of genus (7, (G) ? 1). TABLE OF CONTENTS CHAPTER Page I INTRODUCTION 1. 1 Overview 1. 2 Graphs and Relationships Used...

  11. On Products and Line Graphs of Signed Graphs, their Eigenvalues and Energy

    E-Print Network [OSTI]

    Zaslavsky, Thomas

    On Products and Line Graphs of Signed Graphs, their Eigenvalues and Energy K.A. Germina, Shahul and Laplacian matrices and their eigenvalues and energies of the general product (non-complete extended p- sum product and the eigenvalues and energy of the product in terms of those of the factor graphs

  12. 3D Graph Visualization with the Oculus Rift Virtual Graph Reality

    E-Print Network [OSTI]

    Wismath, Stephen

    3D Graph Visualization with the Oculus Rift Virtual Graph Reality Farshad Barahimi, Stephen Wismath regarding three- dimensional (3D) representations of graphs. However, the actual usefulness of such 3D reality environment such as a CAVE, or · printed as a physical model with a 3D printer. Early studies

  13. Graph-Theoretic Generation of Assembly Plans Part I: Correct Generation of Precedence Graphs

    E-Print Network [OSTI]

    Wu, David

    1 Graph-Theoretic Generation of Assembly Plans Part I: Correct Generation of Precedence Graphs Lehigh University Bethlehem, Pennsylvania Abstract Automatic generation and selection of assembly plans a graph-theoretic scheme for the generation of assembly plans. Our scheme involves decomposing the CSP

  14. On the Cohen-Macaulay graphs and girth

    E-Print Network [OSTI]

    Hoang, Do Trong; Trung, Tran Nam

    2012-01-01T23:59:59.000Z

    In this paper we investigate the Cohen-Macaulay property of graphs versus girth. In particular, we classify Cohen-Macaulay graphs of girth at least five and planar Gorenstein graphs of girth four.

  15. Graph searching and a generalized parking function

    E-Print Network [OSTI]

    Kostic, Dimitrije Nenad

    2009-05-15T23:59:59.000Z

    introduced a new generalization, the G-multiparking function, where G is a simple graph on a totally ordered vertex set {1, 2, . . . , n}. We give an algorithm that converts a G-multiparking function into a rooted spanning forest of G by using a graph...

  16. Directed Graphs, Decompositions, and Spatial Linkages

    E-Print Network [OSTI]

    Shai, Offer; Whiteley, Walter

    2010-01-01T23:59:59.000Z

    The decomposition of a system of constraints into small basic components is an important tool of design and analysis. Specifically, the decomposition of a linkage into minimal components is a central tool of analysis and synthesis of linkages. In this paper we prove that every pinned 3-isostatic (minimally rigid) graph (grounded linkage) has a unique decomposition into minimal strongly connected components (in the sense of directed graphs) which we call 3-Assur graphs. This analysis extends the Assur decompositions of plane linkages previously studied in the mathematical and the mechanical engineering literature. These 3-Assur graphs are the central building blocks for all kinematic linkages in 3-space. They share a number of key combinatorial and geometric properties with the 2-Assur graphs, including an associated lower block-triangular decomposition of the pinned rigidity matrix which provides a format for extending the motion induced by inserting one driver in a bottom Assur linkage to the joints of the e...

  17. What Energy Functions Can Be Minimized via Graph Cuts?

    E-Print Network [OSTI]

    Field, David

    What Energy Functions Can Be Minimized via Graph Cuts? Vladimir Kolmogorov, Member, IEEE, and Ramin been developed to solve energy minimization problems in computer vision. Each of these techniques constructs a graph such that the minimum cut on the graph also minimizes the energy. Yet, because these graph

  18. What Energy Functions can be Minimized via Graph Cuts?

    E-Print Network [OSTI]

    Field, David

    What Energy Functions can be Minimized via Graph Cuts? Vladimir Kolmogorov and Ramin Zabih Computer. In the last few years, several new algorithms based on graph cuts have been developed to solve energy cut on the graph also minimizes the energy. Yet because these graph constructions are complex

  19. Attack Graphs for Sensor Placement, Alert Prioritization, and Attack Response

    E-Print Network [OSTI]

    Noel, Steven

    1 Attack Graphs for Sensor Placement, Alert Prioritization, and Attack Response Steven Noel of IDS alarms, using attack graph analysis. Our attack graphs predict the various possible ways and attacker exploits provides an attack graph showing all possible paths to critical assets. We then place IDS

  20. A Note on Hamilton Cycles in Kneser Graphs Ian Shields

    E-Print Network [OSTI]

    Savage, Carla D.

    A Note on Hamilton Cycles in Kneser Graphs Ian Shields IBM P.O. Box 12195 Research Triangle Park) have Hamilton cycles when n #20; 27. A similar result is shown for bipartite Kneser graphs. 1 for Hamilton cycles in Kneser graphs, K(n; k), and bipartite Kneser graphs, H(n; k). With the exception

  1. Gibbs Measures and Phase Transitions on Sparse Random Graphs

    E-Print Network [OSTI]

    Montanari, Annamaria

    regular graphs . . . . . . . . . . . . . . 87 6.2 Hyper-loops, hypergraphs, cores and a peeling algorithm

  2. Discrete Applied Mathematics 121 (2002) 139153 NeST graphs

    E-Print Network [OSTI]

    Hayward, Ryan B.

    Discrete Applied Mathematics 121 (2002) 139¬≠153 NeST graphs Ryan B. Haywarda; , Paul E. Kearneyb; received in revised form 14 March 2001; accepted 26 March 2001 Abstract We establish results on NeST graphs show the equivalence of proper NeST graphs and unit NeST graphs, the equivalence of √Ņxed distance NeST

  3. EuroComb 2005 DMTCS proc. AE, 2005, 389--396 Acyclic Coloring of Graphs of Maximum

    E-Print Network [OSTI]

    Fertin, Guillaume

    for several families F of graphs such as planar graphs [Bor79], planar graphs with ``large'' girth [BKW99], 1

  4. Revisiting Interval Graphs for Network Science

    E-Print Network [OSTI]

    Loe, Chuan Wen

    2015-01-01T23:59:59.000Z

    The vertices of an interval graph represent intervals over a real line where overlapping intervals denote that their corresponding vertices are adjacent. This implies that the vertices are measurable by a metric and there exists a linear structure in the system. The generalization is an embedding of a graph onto a multi-dimensional Euclidean space and it was used by scientists to study the multi-relational complexity of ecology. However the research went out of fashion in the 1980s and was not revisited when Network Science recently expressed interests with multi-relational networks known as multiplexes. This paper studies interval graphs from the perspective of Network Science.

  5. A role for matrices in graph theory

    E-Print Network [OSTI]

    McLean, John Patrick

    1971-01-01T23:59:59.000Z

    A ROLE FOR MATRICES IN GRAPH THEORY A Thesis by John Patrick McLean Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE May 1971 Ma]or Subject: Mathematics... A ROLE FOR MATRICES IN GRAPH THEORY A Thesis by John Patrick McLean Approved as to style and content by: (Chairman of Committee) (Head of Department) I (Member) (Member) May 1971 tp Qey $ ABSTRACT A Role for Matrices in Graph Theory...

  6. From graphs to signals and back: Identification of graph structures using spectral analysis

    E-Print Network [OSTI]

    Hamon, Ronan; Flandrin, Patrick; Robardet, Cťline

    2015-01-01T23:59:59.000Z

    Many systems comprising entities in interactions can be represented as graphs, whose structure gives significant insights about how these systems work. Network theory has undergone further developments, in particular in relation to detection of communities in graphs, to catch this structure. Recently, an approach has been proposed to transform a graph into a collection of signals: Using a multidimensional scaling technique on a distance matrix representing relations between vertices of the graph, points in a Euclidean space are obtained and interpreted as signals, indexed by the vertices. In this article, we propose several extensions to this approach, developing a framework to study graph structures using signal processing tools. We first extend the current methodology, enabling us to highlight connections between properties of signals and graph structures, such as communities, regularity or randomness, as well as combinations of those. A robust inverse transformation method is next described, taking into ac...

  7. Continuous-time quantum walks on star graphs

    SciTech Connect (OSTI)

    Salimi, S. [Department of Physics, University of Kurdistan, P.O. Box 66177-15175, Sanandaj (Iran, Islamic Republic of)], E-mail: shsalimi@uok.ac.ir

    2009-06-15T23:59:59.000Z

    In this paper, we investigate continuous-time quantum walk on star graphs. It is shown that quantum central limit theorem for a continuous-time quantum walk on star graphs for N-fold star power graph, which are invariant under the quantum component of adjacency matrix, converges to continuous-time quantum walk on K{sub 2} graphs (complete graph with two vertices) and the probability of observing walk tends to the uniform distribution.

  8. Bipartite graph partitioning and data clustering

    SciTech Connect (OSTI)

    Zha, Hongyuan; He, Xiaofeng; Ding, Chris; Gu, Ming; Simon, Horst D.

    2001-05-07T23:59:59.000Z

    Many data types arising from data mining applications can be modeled as bipartite graphs, examples include terms and documents in a text corpus, customers and purchasing items in market basket analysis and reviewers and movies in a movie recommender system. In this paper, the authors propose a new data clustering method based on partitioning the underlying biopartite graph. The partition is constructed by minimizing a normalized sum of edge weights between unmatched pairs of vertices of the bipartite graph. They show that an approximate solution to the minimization problem can be obtained by computing a partial singular value decomposition (SVD) of the associated edge weight matrix of the bipartite graph. They point out the connection of their clustering algorithm to correspondence analysis used in multivariate analysis. They also briefly discuss the issue of assigning data objects to multiple clusters. In the experimental results, they apply their clustering algorithm to the problem of document clustering to illustrate its effectiveness and efficiency.

  9. The Minimum Rank Problem for Outerplanar Graphs.

    E-Print Network [OSTI]

    Sinkovic, John Henry

    2013-01-01T23:59:59.000Z

    ??Given a simple graph G with vertex set V(G)={1,2,...,n} define S(G) to be the set of all real symmetric matrices A such that for allÖ (more)

  10. Minimum rank of graphs that allow loops.

    E-Print Network [OSTI]

    Mikkelson, Rana C.

    2008-01-01T23:59:59.000Z

    ??The traditional "minimum rank problem" for simple graphs associates a set of symmetric matrices, the zero-nonzero pattern of whose off-diagonal entries are described by theÖ (more)

  11. On semidefinite programming bounds for graph bandwidth

    E-Print Network [OSTI]

    2011-05-24T23:59:59.000Z

    May 24, 2011 ... We propose two new lower bounds on graph bandwidth and cyclic ... matrix computations, parallel computations, VLSI layout, etc; see, for example [19]. ...... problems by SeDuMi [30] using the Yalmip interface [22] with Matlab.

  12. Graph Implementations for Nonsmooth Convex Programs

    E-Print Network [OSTI]

    2007-09-07T23:59:59.000Z

    Summary. We describe graph implementations, a generic method for represent- ... object-oriented features of Matlab to turn it into an optimization modeling language: ..... For matrix and array expressions, these rules are applied on an elemen-.

  13. Forced orientation of graphs Babak Farzad

    E-Print Network [OSTI]

    Toronto, University of

    Forced orientation of graphs Babak Farzad Mohammad Mahdian Ebad S. Mahmoodian Amin Saberiß Bardia, USA. (saberi@cc.gatech.edu) ∂ Department of Computer Science, UIUC, Urbana, USA. (sadri@cs.uiuc.edu) 1

  14. Hamilton Paths in Generalized Petersen Graphs.

    E-Print Network [OSTI]

    Pensaert, William

    2006-01-01T23:59:59.000Z

    ??This thesis puts forward the conjecture that for n > 3k with k > 2, the generalized Petersen graph, GP(n,k) is Hamilton-laceable if n isÖ (more)

  15. Graph Summarization with Bounded Error Saket Navlakha

    E-Print Network [OSTI]

    Gruner, Daniel S.

    of Maryland College Park, MD, USA-20742 saket@cs.umd.edu Rajeev Rastogi Yahoo! Labs Bangalore, India rrastogi@yahoo-inc Graphs are a fundamental abstraction that have been em- ployed for centuries to model real-world systems

  16. Accelerating semantic graph databases on commodity clusters

    SciTech Connect (OSTI)

    Morari, Alessandro; Castellana, Vito G.; Haglin, David J.; Feo, John T.; Weaver, Jesse R.; Tumeo, Antonino; Villa, Oreste

    2013-10-06T23:59:59.000Z

    We are developing a full software system for accelerating semantic graph databases on commodity cluster that scales to hundreds of nodes while maintaining constant query throughput. Our framework comprises a SPARQL to C++ compiler, a library of parallel graph methods and a custom multithreaded runtime layer, which provides a Partitioned Global Address Space (PGAS) programming model with fork/join parallelism and automatic load balancing over a commodity clusters. We present preliminary results for the compiler and for the runtime.

  17. 2Cosmic Bar Graphs Galaxy Type

    E-Print Network [OSTI]

    in the cluster are spirals? Problem 2 ­ Gamma-ray bursts happen about once each day. The bar graph to the right there are 160 total galaxies, the fraction of spirals is 137/160 = 0.86, or equivalently 86%. Problem 2 ­ Gamma-ray2Cosmic Bar Graphs 0 20 40 60 80 100 S E SB I Galaxy Type Number 0 200 400 600 800 1000 FB SB Burst

  18. Graph representation of protein free energy landscape

    SciTech Connect (OSTI)

    Li, Minghai; Duan, Mojie; Fan, Jue; Huo, Shuanghong, E-mail: shuo@clarku.edu [Gustaf H. Carlson School of Chemistry and Biochemistry, Clark University, 950 Main Street, Worcester, Massachusetts 01610 (United States)] [Gustaf H. Carlson School of Chemistry and Biochemistry, Clark University, 950 Main Street, Worcester, Massachusetts 01610 (United States); Han, Li [Department of Mathematics and Computer Science, Clark University, 950 Main Street, Worcester, Massachusetts 01610 (United States)] [Department of Mathematics and Computer Science, Clark University, 950 Main Street, Worcester, Massachusetts 01610 (United States)

    2013-11-14T23:59:59.000Z

    The thermodynamics and kinetics of protein folding and protein conformational changes are governed by the underlying free energy landscape. However, the multidimensional nature of the free energy landscape makes it difficult to describe. We propose to use a weighted-graph approach to depict the free energy landscape with the nodes on the graph representing the conformational states and the edge weights reflecting the free energy barriers between the states. Our graph is constructed from a molecular dynamics trajectory and does not involve projecting the multi-dimensional free energy landscape onto a low-dimensional space defined by a few order parameters. The calculation of free energy barriers was based on transition-path theory using the MSMBuilder2 package. We compare our graph with the widely used transition disconnectivity graph (TRDG) which is constructed from the same trajectory and show that our approach gives more accurate description of the free energy landscape than the TRDG approach even though the latter can be organized into a simple tree representation. The weighted-graph is a general approach and can be used on any complex system.

  19. Graph Kernels Based on Relevant Patterns and Cycle Information for Chemoinformatics

    E-Print Network [OSTI]

    Boyer, Edmond

    by combining relevant cycles and newly discovered cycles. Horv¬īath showed that a low number of iterationsGraph Kernels Based on Relevant Patterns and Cycle Information for Chemoinformatics Benoit Ga of view, graph kernels provide a nice framework for combining these two fields. We present in this paper

  20. MadGraph 5 : Going Beyond

    E-Print Network [OSTI]

    Johan Alwall; Michel Herquet; Fabio Maltoni; Olivier Mattelaer; Tim Stelzer

    2011-06-02T23:59:59.000Z

    MadGraph 5 is the new version of the MadGraph matrix element generator, written in the Python programming language. It implements a number of new, efficient algorithms that provide improved performance and functionality in all aspects of the program. It features a new user interface, several new output formats including C++ process libraries for Pythia 8, and full compatibility with FeynRules for new physics models implementation, allowing for event generation for any model that can be written in the form of a Lagrangian. MadGraph 5 builds on the same philosophy as the previous versions, and its design allows it to be used as a collaborative platform where theoretical, phenomenological and simulation projects can be developed and then distributed to the high-energy community. We describe the ideas and the most important developments of the code and illustrate its capabilities through a few simple phenomenological examples.

  1. Streaming Graph Computations with a Helpful Advisor

    E-Print Network [OSTI]

    Cormode, Graham; Thaler, Justin

    2010-01-01T23:59:59.000Z

    Motivated by the trend to outsource work to commercial cloud computing services, we consider a variation of the streaming paradigm where a streaming algorithm can be assisted by a powerful helper that can provide annotations to the data stream. We extend previous work on such {\\em annotation models} by considering a number of graph streaming problems. Without annotations, streaming algorithms for graph problems generally require significant memory; we show that for many standard problems, including all graph problems that can be expressed with totally unimodular integer programming formulations, only a constant number of hash values are needed for single-pass algorithms given linear-sized annotations. We also obtain a protocol achieving \\textit{optimal} tradeoffs between annotation length and memory usage for matrix-vector multiplication; this result contributes to a trend of recent research on numerical linear algebra in streaming models.

  2. Circuit and bond polytopes on series-parallel graphs$

    E-Print Network [OSTI]

    2014-07-10T23:59:59.000Z

    Jul 10, 2014 ... M0 = IS, for some star decomposition S of G, and Mi?Ni is a cut of G, for i = 1,..., k. 2. Circuit polytope on series-parallel graphs. Given a graph G†...

  3. An efficient semidefinite programming relaxation for the graph ...

    E-Print Network [OSTI]

    2012-08-28T23:59:59.000Z

    The general graph partition problem (GPP) is defined as follows. Let G = (V ... We denote by A the adjacency matrix of G. For a given partition of the graph into k.

  4. Generating Random Graphs with Large Girth Mohsen Bayati

    E-Print Network [OSTI]

    Saberi, Amin

    Generating Random Graphs with Large Girth Mohsen Bayati Andrea Montanari Amin Saberi Abstract We; saberi@stanford.edu. 1 #12;free graphs are close to bipartite. We show that our new algorithm guarantees

  5. GARNET : a Graphical Attack graph and Reachability Network Evaluation Tool

    E-Print Network [OSTI]

    Williams, Leevar (Leevar Christoff)

    2008-01-01T23:59:59.000Z

    Attack graphs are valuable tools in the assessment of network security, revealing potential attack paths an adversary could use to gain control of network assets. Creating an effective visualization for attack graphs is ...

  6. Codes on Graphs: Duality and MacWilliams Identities

    E-Print Network [OSTI]

    Forney, G. David, Jr.

    A conceptual framework involving partition functions of normal factor graphs is introduced, paralleling a similar recent development by Al-Bashabsheh and Mao. The partition functions of dual normal factor graphs are shown ...

  7. Scalable Parallel Algorithms for Massive Scale-free Graphs

    E-Print Network [OSTI]

    Pearce, Roger Allan

    2013-12-05T23:59:59.000Z

    Efficiently storing and processing massive graph data sets is a challenging problem as researchers seek to leverage ďBig DataĒ to answer next-generation scientific questions. New techniques are required to process large scale-free graphs in shared...

  8. Math 564 Graph Theory Fall 2008 Instructor Amites Sarkar

    E-Print Network [OSTI]

    Sarkar, Amites

    Math 564 Graph Theory Fall 2008 Instructor Amites Sarkar Text Pearls in Graph Theory (Dover Edition and Fridays, in 216 Bond Hall. My phone number is 650 7569 and my e-mail is amites.sarkar@wwu.edu #12;

  9. Math 564 Graph Theory Fall 2013 Instructor Amites Sarkar

    E-Print Network [OSTI]

    Sarkar, Amites

    Math 564 Graph Theory Fall 2013 Instructor Amites Sarkar Text Modern Graph Theory B¬īela Bollob, Tuesdays, Wednesdays and Fridays, in 216 Bond Hall. My phone number is 650 7569 and my e-mail is amites.sarkar

  10. Reformulation of a model for hierarchical divisive graph modularity ...

    E-Print Network [OSTI]

    2012-01-31T23:59:59.000Z

    Agarwal, G., & Kempe, D. (2008). Modularity-maximizing graph communities via mathematical program- ming. The European Physical Journal B - Condensed†...

  11. Problems of Distance-Regular Graphs Hiroshi Suzuki

    E-Print Network [OSTI]

    Xi, Changchang

    . Biggs, Algebraic Graph Theory Second Edition, Cambridge U. P., Cambridge 1993. [16] N. L. Biggs, A. G

  12. Bose-Einstein condensation on quantum graphs

    E-Print Network [OSTI]

    Jens Bolte; Joachim Kerner

    2014-03-02T23:59:59.000Z

    We present results on Bose-Einstein condensation (BEC) on general compact quantum graphs, i.e., one-dimensional systems with a (potentially) complex topology. We first investigate non-interacting many-particle systems and provide a complete classification of systems that exhibit condensation. We then consider models with interactions that consist of a singular part as well as a hardcore part. In this way we obtain generalisations of the Tonks-Girardeau gas to graphs. For this we find an absence of phase transitions which then indicates an absence of BEC.

  13. Hiroshi Ishikawa A Practical Introduction to Graph Cut

    E-Print Network [OSTI]

    Ishikawa, Hiroshi

    Technology Contents Overview / Brief history Energy minimization Graphs and their minimum cuts Energy Elevation map #12;History Probablistic methods (SA, ICM,...) have been used for energy minimization OR has Overview / Brief history Energy minimization Graphs and their minimum cuts Energy minimization via graph

  14. Hamiltonian Cycles on Symmetrical Graphs Carlo H. Squin

    E-Print Network [OSTI]

    O'Brien, James F.

    Hamiltonian Cycles on Symmetrical Graphs Carlo H. Séquin Computer Science Division, EECS Department-connected symmetrical graphs are colored so that they form Hamiltonian cycles. As an introduction we discuss is to color all edges in these graphs with multi- ple congruent copies of Hamiltonian cycles exhibiting

  15. Optimal IDS Sensor Placement And Alert Prioritization Using Attack Graphs

    E-Print Network [OSTI]

    Noel, Steven

    1 Optimal IDS Sensor Placement And Alert Prioritization Using Attack Graphs Steven Noel and Sushil optimally place intrusion detection system (IDS) sensors and prioritize IDS alerts using attack graph. The set of all such paths through the network constitutes an attack graph, which we aggregate according

  16. Improving Attack Graph Visualization through Data Reduction and Attack Grouping

    E-Print Network [OSTI]

    Ou, Xinming "Simon"

    Improving Attack Graph Visualization through Data Reduction and Attack Grouping John Homer1 Laboratory, USA Abstract. Various tools exist to analyze enterprise network systems and to produce attack graphs detailing how attackers might penetrate into the system. These attack graphs, however, are often

  17. Compatible Hamilton cycles in Dirac graphs Michael Krivelevich

    E-Print Network [OSTI]

    Krivelevich, Michael

    Compatible Hamilton cycles in Dirac graphs Michael Krivelevich Choongbum Lee Benny Sudakov system F over a Dirac graph G, there exists a Hamilton cycle compatible with F. This settles in a very strong form, a conjecture of H¨aggkvist from 1988. 1 Introduction A Hamilton cycle in a graph G

  18. Infinite Hamilton Cycles in Squares of Locally Finite Graphs

    E-Print Network [OSTI]

    Diestel, Reinhard

    Infinite Hamilton Cycles in Squares of Locally Finite Graphs Agelos Georgakopoulos Abstract We prove Diestel's conjecture that the square G2 of a 2-connected locally finite graph G has a Hamilton if and only if they have distance at most n in G. A Hamilton cycle in a graph is a cycle containing all its

  19. Robust Self-assembly of Graphs Stanislav Angelov1

    E-Print Network [OSTI]

    Pennsylvania, University of

    Robust Self-assembly of Graphs Stanislav Angelov1 , Sanjeev Khanna2 , and Mirk¬īo Visontai3 1 Google, University of Pennsylvania Philadelphia, PA 19104, USA mirko@math.upenn.edu Abstract. Self-assembly studied model of self-assembly is the Accretive Graph Assembly Model whereby an edge-weighted graph

  20. Simultaneous Segmentation and Filtering via Reduced Graph Cuts

    E-Print Network [OSTI]

    Malgouyres, François

    provides small graphs while preserving thin structures but do not offer low memory usage when the amount [7,4,13]. In [7], binary energy functions are minimized for the shape fitting problem with graph cutsSimultaneous Segmentation and Filtering via Reduced Graph Cuts N. Lermé F. Malgouyres LAGA UMR CNRS

  1. Cellular Algebras and Graph Invariants Based on Quantum Walks

    E-Print Network [OSTI]

    Jamie Smith

    2011-03-01T23:59:59.000Z

    We consider two graph invariants inspired by quantum walks- one in continuous time and one in discrete time. We will associate a matrix algebra called a cellular algebra with every graph. We show that, if the cellular algebras of two graphs have a similar structure, then they are not distinguished by either of the proposed invariants.

  2. Inference of Edge Replacement Graph Grammars Jacek P. Kukluk1

    E-Print Network [OSTI]

    Holder, Lawrence B.

    Inference of Edge Replacement Graph Grammars Jacek P. Kukluk1 , Lawrence B. Holder2 , and Diane J@eecs.wsu.edu Abstract We describe an algorithm and experiments for inference of edge replacement graph grammars for inference of Node Replacement Recursive Graph Grammars [7]. In this paper we describe an approach

  3. Bicycles and Left-Right Tours in Locally Finite Graphs

    E-Print Network [OSTI]

    Diestel, Reinhard

    Bicycles and Left-Right Tours in Locally Finite Graphs von Melanie Win Myint, M. S. Dem Department-Right Tours 29 6 LRTs Generate the Bicycle Space 43 7 The ABL Planarity Criterion 53 8 Pedestrian Graphs 69 bicycles and some other concepts they relate to, such as left- right tours and pedestrian graphs

  4. Dominating Set on Bipartite Graphs Mathieu Liedloff

    E-Print Network [OSTI]

    Liedloff, Mathieu

    .5263n ) time algorithm using polynomial space and an O(1.5137n ) time algorithm using exponential space ) time and polynomial space algorithm, and an O(1.5063n ) time algorithm that uses exponential space. We]). Known results. Given a graph G = (V, E), a subset D V is a dominating set of G if every vertex of V

  5. Optimizing Path Query Performance: Graph Clustering Strategies

    E-Print Network [OSTI]

    ywh@us.ibm.com Ning Jingz Changsha Institute of Technology jning@eecs.umich.edu Elke A. Rundensteinerx not incur any run-time cost, requires no auxiliary data structures, and is complimentary to many of the performance of these graph clustering techniques using an actual city road network as well as randomly

  6. Graph-Theoretic Scagnostics Leland Wilkinson

    E-Print Network [OSTI]

    Grossman, Robert

    Tukey and Tukey scagnostics and develop graph- theoretic methods for implementing their procedure, statistical graphics 1 INTRODUCTION Around 20 years ago, John and Paul Tukey developed an ex- ploratory of the method were never published. Paul Tukey did offer more detail at an IMA visualization workshop a few

  7. Graph Grammars for Self Assembling Robotic Systems

    E-Print Network [OSTI]

    Ghrist, Robert W.

    Graph Grammars for Self Assembling Robotic Systems Eric Klavins Electrical Engineering University numbers of objects so that they perform some global task. Nevertheless, there are examples of sophisticated machines, such as the ribosome or the mechanical motor in the bacterial flagellum, that seem

  8. NEST REPRESENTATIONS OF DIRECTED GRAPH ALGEBRAS

    E-Print Network [OSTI]

    Katsoulis, Elias G.

    NEST REPRESENTATIONS OF DIRECTED GRAPH ALGEBRAS KENNETH R. DAVIDSON AND ELIAS KATSOULIS Abstract. This paper is a comprehensive study of the nest rep- resentations for the free semigroupoid algebra LG that the finite dimensional nest representations sep- arate the points in LG, and a fortiori, in T + (G

  9. The Web Graph of a Tourism System

    E-Print Network [OSTI]

    Baggio, R

    2006-01-01T23:59:59.000Z

    The website network of a tourism destination is examined. The main statistical characteristics of the underlying graph are calculated. The topology of the network is similar to the one characterizing similar systems. However, some differences are found, mainly due to the relatively poor connectivity among the vertices of the network.

  10. Flexible Layered Authentication Graph for Multimedia Streaming

    E-Print Network [OSTI]

    Sun, Qibin

    With the increasing demand on multimedia streaming in more and more applications, security issues such as integrity side, lost packets are dropped from the graph and a packet is verifiable if it has a path and all subsequent packets become not verifiable. EMSS [4] makes a great improvement by building multiple

  11. Lessons 6 Graphs of Functional Models

    E-Print Network [OSTI]

    2013-08-30T23:59:59.000Z

    Aug 30, 2013 ... One of the problems (#1) illustrates the principle of supply and demand, ... All of the problems involve building up a function model (see Lesson 5) ... Granite Management rents out several apartment complexes in the .... Side. 0.001 per cm2. Bottom. 0.005 per cm2. Lessons 6 Graphs of Functional Models.

  12. Line graphs e contrazioni: un approccio rigoroso alla space syntax

    E-Print Network [OSTI]

    D'Autilia, Roberto

    2015-01-01T23:59:59.000Z

    The methods of the space syntax have been the subject of extensive discussion, and several techniques to identify the axis lines have been proposed. The space syntax can be represented in terms of line graph, a graphs defined on the edge of a given primary graph. By means of the line graph algorithms, a system of labels defined on the edges of the primary graph is transformed into a system of labels on the vertices of the line graph. The contraction of adjacent edges with the same label allows to build a more general graph than those generated with the methods of the space syntax. By means of the functions implemented in Mathematica is therefore possible to redefine the space syntax on any system of urban quantities (labels) and reproduce the results of the axial lines as a special case. As an example is discussed a possible application of the method to the urban noise analysis.

  13. Data-flow graphs as a model of parallel complexity

    SciTech Connect (OSTI)

    Campbell, M.L.

    1987-01-01T23:59:59.000Z

    A new model of parallel computation based on data-flow graphs is introduced, which is specifically oriented towards complexity theory. Data-flow graphs are capable of illustrating properties of synchronous, asynchronous, and nondeterministic computations. Sufficient conditions are derived for asynchronous data-flow graphs to be determinate, i.e., all possible computations are finite and yield the same result. For determinate graphs, it is shown that the synchronous computation is as fast as any asynchronous computation. An algorithm is presented that transforms a nondeterminate data-flow graphs into a synchronous determinate one. The basic data-flow graph idea is extended into a model with greater potential parallelism, called the Uniform Data Flow Graph Family (UDFGF) Model. It is proved that time and space for the UDFGF model are polynomially related to reversal and space for the Turing Machine model, in both the deterministic and nondeterministic cases. In addition to forming an abstract computational model, data-flow graphs are parallel programs for real multiprocessors. Given a data flow graph program and a multiprocessor, each node of the graph must be assigned to one of the processors. It is proved that this problem is intractable, and a practical algorithm to find approximate solutions for it is presented.

  14. Statistical Properties of Quantum Graph Spectra

    E-Print Network [OSTI]

    Yu. Dabaghian

    2006-08-09T23:59:59.000Z

    A general analytical approach to the statistical description of quantum graph spectra based on the exact periodic orbit expansions of quantum levels is discussed. The exact and approximate expressions obtained in \\cite{Anima} for the probability distribution functions using the spectral hierarchy method are analyzed. In addition, the mechanism of appearance of the universal statistical properties of spectral fluctuations of quantum-chaotic systems is considered in terms of the semiclassical theory of periodic orbits.

  15. Analysis of beacon triangulation in random graphs

    E-Print Network [OSTI]

    Kakarlapudi, Geetha

    2005-02-17T23:59:59.000Z

    . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 viii LIST OF TABLES TABLE Page I Beacons needed for different n to avoid conflicts . . . . . . . . . . . . 13 II Beacons needed for different n to make pu(n) equal to one for lambda = 10 from our model and simulation... . . . . . . . . . . . . . . . . . 25 III Beacons needed for different n to make pu(n) equal to one for lambda = 10 from our simulation data for G(n,p) graph and uniform distribution case . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 IV Beacons needed for different n...

  16. k-Boson Quantum Walks Do Not Distinguish Arbitrary Graphs

    E-Print Network [OSTI]

    Jamie Smith

    2010-04-01T23:59:59.000Z

    In this paper, we define k-equivalence, a relation on graphs that relies on their associated cellular algebras. We show that a k-Boson quantum walk cannot distinguish pairs of graphs that are k- equivalent. The existence of pairs of k-equivalent graphs has been shown by Ponomarenko et al. [2, 6]. This gives a negative answer to a question posed by Gamble et al. [7].

  17. Dynamics of entanglement of bosonic modes on symmetric graphs

    E-Print Network [OSTI]

    F. Ghahhari; V. Karimipour; R. Shahrokhshahi

    2006-11-23T23:59:59.000Z

    We investigate the dynamics of an initially disentangled Gaussian state on a general finite symmetric graph. As concrete examples we obtain properties of this dynamics on mean field graphs of arbitrary sizes. In the same way that chains can be used for transmitting entanglement by their natural dynamics, these graphs can be used to store entanglement. We also consider two kinds of regular polyhedron which show interesting features of entanglement sharing.

  18. Independent set problems and odd-hole-preserving graph reductions

    E-Print Network [OSTI]

    Warren, Jeffrey Scott

    2009-05-15T23:59:59.000Z

    to provide a polynomial-time reduction in the size of the input required to decide the perfection or imperfection of a graph....

  19. Computing the stability number of a graph via linear and ...

    E-Print Network [OSTI]

    2006-04-27T23:59:59.000Z

    Throughout the paper A(G) ? Sn will denote the adjacency matrix of the graph G, that is, the (i, ..... Some matlab code that constructs the relevant semidefi-.

  20. Generating Random Graphs with Large Girth Mohsen Bayati

    E-Print Network [OSTI]

    Montanari, Annamaria

    Generating Random Graphs with Large Girth Mohsen Bayati Andrea Montanari Amin Saberi Abstract We for Computational and Mathematical Engineering, Stanford University; saberi@stanford.edu. knowledge

  1. A notable family of entire intrinsic minimal graph...

    E-Print Network [OSTI]

    2006-09-09T23:59:59.000Z

    to C1(O). This notion of C2 surface obviously includes the entire intrinsic graphs ...... F. Serra Cassano, Surface measures in Carnot-Carathťodory spaces, Calc.

  2. Graphs are among the most important abstract data structures in computer sci-ence, and the algorithms that operate on them are critical to modern life. Graphs

    E-Print Network [OSTI]

    Kepner, Jeremy

    description that assumes a sparse matrix representation of the graph, and operates on that matrix with linear environments (e.g., Matlab ). (2) Ease of implementation. Parallel graph algorithms are notoriously difficult computation of graph algorithms. (3) Performance. Graph algorithms expressed by a series of sparse matrix

  3. Visualization Graph | OpenEI Community

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Office of InspectorConcentrating SolarElectric Coop,Save EnergyGlouster,Winside, Nebraska (UtilityVirginiaNoGraph Home

  4. Algorithms to Compute Minimum Cycle Basis in Directed Graphs #

    E-Print Network [OSTI]

    Mehlhorn, Kurt

    , . . . ,C d whose incidence vectors permit a unique linear combination of the incidence vector of any cycleAlgorithms to Compute Minimum Cycle Basis in Directed Graphs # Telikepalli Kavitha + Kurt Mehlhorn # Abstract We consider the problem of computing a minimum cycle basis in a di­ rected graph G with m arcs

  5. Deciding Timed Bisimulation for Timed Automata Using Zone Valuation Graph

    E-Print Network [OSTI]

    Prasad, Sanjiva

    Deciding Timed Bisimulation for Timed Automata Using Zone Valuation Graph Shibashis Guha, Chinmay was first proved to be decidable for timed automata by Cerans using a product construction method on region graph. Several other methods have been proposed in the literature since then for decid- ing timed

  6. Rank Synopses for Efficient Time Travel on the Web Graph

    E-Print Network [OSTI]

    Rank Synopses for Efficient Time Travel on the Web Graph Klaus Berberich, Srikanta Bedathur}@mpi-inf.mpg.de ProblemProblem SolutionSolution ExperimentsExperiments Step 1: PageRank Normalization We normalize PageRank scores computed on Gt ( Vt, Et ) (i.e., the graph at time t ) dividing by the lower bound PageRank score

  7. Semidefinite programming and eigenvalue bounds for the graph ...

    E-Print Network [OSTI]

    2013-11-26T23:59:59.000Z

    The graph partition problem is the problem of partitioning the vertex set of a graph ... In this paper we simplify a known matrix-lifting semidefinite ...... [44] Sturm, J.F.: Using SeDuMi 1.02, a MATLAB toolbox for optimization over symmetric cones.

  8. ADAGE: A software package for analyzing graph evolution

    E-Print Network [OSTI]

    graph evolution. 2.2 Using ADAGE 2.2.1 Installation ADAGE was built for use on MATLAB 2007 version. In this case input is a string. If the MATLAB matrix has already been saved, simply run > input = loadADAGE: A software package for analyzing graph evolution Mary McGlohon, Christos Faloutsos May 2007

  9. MATLAB Tutorial Getting Started with Calculations, Graphing and Programming

    E-Print Network [OSTI]

    Weinberger, Hans

    MATLAB Tutorial Getting Started with Calculations, Graphing and Programming Nicholas R. Kirchner UI 2 Calculations with MATLAB Standard Calculations and Variables Matrices and Vectors 3 Graphing NRK;Matrices and Vectors, Definitions MATLAB is short for MATrix LABoratory. It was built for high-speed matrix

  10. Understanding Complex Network Attack Graphs through Clustered Adjacency Matrices

    E-Print Network [OSTI]

    Noel, Steven

    Understanding Complex Network Attack Graphs through Clustered Adjacency Matrices Steven Noel}@gmu.edu Abstract We apply adjacency matrix clustering to network attack graphs for attack correlation, prediction, and hypothesizing. We self-multiply the clustered adjacency matrices to show attacker reachability across

  11. Improving Attack Graph Visualization through Data Reduction and Attack Grouping

    SciTech Connect (OSTI)

    John Homer; Ashok Varikuti; Xinming Ou; Miles A. McQueen

    2008-09-01T23:59:59.000Z

    Various tools exist to analyze enterprise network systems and to produce attack graphs detailing how attackers might penetrate into the system. These attack graphs, however, are often complex and difficult to comprehend fully, and a human user may find it problematic to reach appropriate configuration decisions. This paper presents methodologies that can 1) automatically identify portions of an attack graph that do not help a user to understand the core security problems and so can be trimmed, and 2) automatically group similar attack steps as virtual nodes in a model of the network topology, to immediately increase the understandability of the data. We believe both methods are important steps toward improving visualization of attack graphs to make them more useful in configuration management for large enterprise networks. We implemented our methods using one of the existing attack-graph toolkits. Initial experimentation shows that the proposed approaches can 1) significantly reduce the complexity of attack graphs by trimming a large portion of the graph that is not needed for a user to understand the security problem, and 2) significantly increase the accessibility and understandability of the data presented in the attack graph by clearly showing, within a generated visualization of the network topology, the number and type of potential attacks to which each host is exposed.

  12. Scaling Semantic Graph Databases in Size and Performance

    SciTech Connect (OSTI)

    Morari, Alessandro; Castellana, Vito G.; Villa, Oreste; Tumeo, Antonino; Weaver, Jesse R.; Haglin, David J.; Choudhury, Sutanay; Feo, John T.

    2014-08-06T23:59:59.000Z

    In this paper we present SGEM, a full software system for accelerating large-scale semantic graph databases on commodity clusters. Unlike current approaches, SGEM addresses semantic graph databases by only employing graph methods at all the levels of the stack. On one hand, this allows exploiting the space efficiency of graph data structures and the inherent parallelism of graph algorithms. These features adapt well to the increasing system memory and core counts of modern commodity clusters. On the other hand, however, these systems are optimized for regular computation and batched data transfers, while graph methods usually are irregular and generate fine-grained data accesses with poor spatial and temporal locality. Our framework comprises a SPARQL to data parallel C compiler, a library of parallel graph methods and a custom, multithreaded runtime system. We introduce our stack, motivate its advantages with respect to other solutions and show how we solved the challenges posed by irregular behaviors. We present the result of our software stack on the Berlin SPARQL benchmarks with datasets up to 10 billion triples (a triple corresponds to a graph edge), demonstrating scaling in dataset size and in performance as more nodes are added to the cluster.

  13. A Surface Reconstruction Method Using Global Graph Cut Optimization

    E-Print Network [OSTI]

    Paris, Sylvain

    SAR (China) 1 sparis@csail.mit.edu -- Sylvain Paris has worked on this project during his PhD at ARTIS calibrated images mainly has been approached using local methods, either as a continuous optimization problem of a pixel. Index Terms Graph flow, graph cut, 3D reconstruction from calibrated cameras, discontinuities

  14. A Surface Reconstruction Method Using Global Graph Cut Optimization

    E-Print Network [OSTI]

    Paris, Sylvain

    SAR (China) 1sparis@csail.mit.edu ­ Sylvain Paris has worked on this project during his PhD at ARTIS calibrated images mainly has been approached using local methods, either as a continuous optimization problem of a pixel. Index Terms Graph flow, graph cut, 3D reconstruction from calibrated cameras, discontinuities

  15. A Surface Reconstruction Method Using Global Graph Cut Optimization

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    SAR (China) 1sparis@csail.mit.edu ­ Sylvain Paris has worked on this project during his PhD at ARTIS reconstruction from multiple calibrated images mainly has been approached using local methods, either to 1/10th of a pixel. Index Terms Graph flow, graph cut, 3D reconstruction from calibrated cameras

  16. Resource Minimized Static Mapping and Dynamic Scheduling of SDF Graphs

    E-Print Network [OSTI]

    Ha, Soonhoi

    Resource Minimized Static Mapping and Dynamic Scheduling of SDF Graphs Jinwoo Kim, Tae-ho Shin than the previous approaches. Keywords-Mapping, buffer size minimization, SDF graph, dynamic scheduling a model-based approach based on SDF (synchronous data flow) model. Since the parallelism of an application

  17. Synthesis of Parallel Hardware Implementations from Synchronous Dataflow Graph Specifications

    E-Print Network [OSTI]

    of automated register­transfer level (RTL) VHDL code generation from synchronous dataflow (SDF) graph for mapping applications specified in SDF to parallel digital hardware implementations. Two styles synthesis from SDF graphs is presented. In order to minimize cost while meeting performance require­ ments

  18. Including Blind Students in Computer Science Through Access to Graphs

    E-Print Network [OSTI]

    Young, R. Michael

    Including Blind Students in Computer Science Through Access to Graphs Suzanne Balik, Sean Mealin SKetching tool, GSK, to provide blind and sighted people with a means to create, examine, and share graphs (node-link diagrams) in real-time. GSK proved very effective for one blind computer science student

  19. Video Denoising and Simplification Via Discrete Regularization on Graphs

    E-Print Network [OSTI]

    Paris-Sud XI, Universitť de

    Video Denoising and Simplification Via Discrete Regularization on Graphs Mahmoud Ghoniem, Youssef algorithms for video de- noising and simplification based on discrete regularization on graphs. The main difference between video and image denoising is the temporal redundancy in video sequences. Recent works

  20. VIDEO SUMMARIZATION BY VIDEO STRUCTURE ANALYSIS AND GRAPH OPTIMIZATION

    E-Print Network [OSTI]

    King, Kuo Chin Irwin

    VIDEO SUMMARIZATION BY VIDEO STRUCTURE ANALYSIS AND GRAPH OPTIMIZATION Shi Lu, Irwin King video summarization method that combines video structure analysis and graph optimiza- tion. First, we analyze the structure of the video, find the boundaries of video scenes, then we calculate each scene

  1. Groups generated by bounded automata and their schreier graphs

    E-Print Network [OSTI]

    Bondarenko, Ievgen

    2009-05-15T23:59:59.000Z

    that the Schreier graphs on levels of automaton groups can be constructed by an iterative procedure of inflation of graphs. This was used to associate a piecewise linear map of the form fK(v) = minA?KAv, where K is a finite set of nonnegative matrices, with every...

  2. Bicyclic graphs with exactly two main signless Laplacian eigenvalues

    E-Print Network [OSTI]

    Huang, He

    2012-01-01T23:59:59.000Z

    A signless Laplacian eigenvalue of a graph $G$ is called a main signless Laplacian eigenvalue if it has an eigenvector the sum of whose entries is not equal to zero. In this paper, all connected bicyclic graphs with exactly two main eigenvalues are determined.

  3. Motorcycle Graphs and Straight Skeletons Siu-Wing Cheng

    E-Print Network [OSTI]

    Vigneron, Antoine

    Motorcycle Graphs and Straight Skeletons Siu-Wing Cheng Antoine Vigneron March 17, 2005 Abstract We present a new algorithm to compute motorcycle graphs. It runs in O(n n log n) time when n is the number of motorcycles. We give a new characterization of the straight skeleton of a non

  4. On bounding the bandwidth of graphs with symmetry - Optimization ...

    E-Print Network [OSTI]

    2013-08-08T23:59:59.000Z

    Hamming graph H(2,q) (also known as the lattice graph) has bandwidth equal to. (q+1)q. 2. ?1 .... 59. 10 3 120. 72. 75. 76. 90. Table 9: Bounds on the bandwidth of K(v,2) and K(v,3). v d meig .... Freeman, San Francisco, 1979. [19] Graham, A.

  5. M&Ms4Graphs: Multi-scale, Multi-dimensional Graph Analytics Tools for Cyber-Security

    E-Print Network [OSTI]

    ranging from micro- (host level) to macro-scale (enterprise level). Achievements · Major release of Graph Library - Exhibit at GraphLab Conference, July 2014 · Selected publications 1. "Towards A Networks-of-Networks of Machine Learning Research, 2014. Rendering of Network Traffic Data Showing Communication between IP

  6. Well performance graph simplifies field calculations

    SciTech Connect (OSTI)

    De Ghetto, G.

    1987-05-01T23:59:59.000Z

    Graphic Methods are widely employed in order to understand overall well behavior using only surface parameters. The authors propose a new graphic method, used successfully by Agip for oil and gas wells in Italy, Libya, Nigeria and Tunisia. The well performance graph helps solve many production problems, including estimation of: inflow performance relationship; causes of rate decline throughout well life; and production rate and bottomhole flowing pressure for various pressures upstream of the surface choke, and vice-versa. This method differs from others by using flow behavior through the choke for both critical and subcritical conditions. Equations describing flow through the formation, string and surface choke are also used. Results are quite reliable when these theoretical equations are calibrated with field data, either from the well concerned or from nearby wells producing the same fluid. This article describes the technique as it applies to oil wells. The methodology for gas wells is similar.

  7. Community detection in directed acyclic graphs

    E-Print Network [OSTI]

    Speidel, Leo; Masuda, Naoki

    2015-01-01T23:59:59.000Z

    Some temporal networks, most notably citation networks, are naturally represented as directed acyclic graphs (DAGs). To detect communities in DAGs, we propose a modularity for DAGs by defining an appropriate null model (i.e., randomized network) respecting the order of nodes. We implement a spectral method to approximately maximize the proposed modularity measure and test the method on citation networks and other DAGs. We find that the attained values of the modularity for DAGs are similar for partitions that we obtain by maximizing the proposed modularity (designed for DAGs), the modularity for undirected networks and that for general directed networks. In other words, if we neglect the order imposed on nodes (and the direction of links) in a given DAG and maximize the conventional modularity measure, the obtained partition is close to the optimal one in the sense of the modularity for DAGs.

  8. Efficient broadcast on random geometric graphs

    SciTech Connect (OSTI)

    Bradonjic, Milan [Los Alamos National Laboratory; Elsasser, Robert [UNIV OF PADERBORN; Friedrich, Tobias [INTERNATIONAL COMPUTER SCI.; Sauerwald, Thomas [INTERNATIONAL COMPUTER SCI.

    2009-01-01T23:59:59.000Z

    A Randon Geometric Graph (RGG) is constructed by distributing n nodes uniformly at random in the unit square and connecting two nodes if their Euclidean distance is at most r, for some prescribed r. They analyze the following randomized broadcast algorithm on RGGs. At the beginning, there is only one informed node. Then in each round, each informed node chooses a neighbor uniformly at random and informs it. They prove that this algorithm informs every node in the largest component of a RGG in {Omicron}({radical}n/r) rounds with high probability. This holds for any value of r larger than the critical value for the emergence of a giant component. In particular, the result implies that the diameter of the giant component is {Theta}({radical}n/r).

  9. Bicyclic graphs with maximal revised Szeged index

    E-Print Network [OSTI]

    Li, Xueliang

    2011-01-01T23:59:59.000Z

    The revised Szeged index $Sz^*(G)$ is defined as $Sz^*(G)=\\sum_{e=uv \\in E}(n_u(e)+ n_0(e)/2)(n_v(e)+ n_0(e)/2),$ where $n_u(e)$ and $n_v(e)$ are, respectively, the number of vertices of $G$ lying closer to vertex $u$ than to vertex $v$ and the number of vertices of $G$ lying closer to vertex $v$ than to vertex $u$, and $n_0(e)$ is the number of vertices equidistant to $u$ and $v$. Hansen used the AutoGraphiX and made the following conjecture about the revised Szeged index for a connected bicyclic graph $G$ of order $n \\geq 6$:

  10. THE MATCHING ENERGY OF A GRAPH IVAN GUTMAN AND STEPHAN WAGNER

    E-Print Network [OSTI]

    Wagner, Stephan

    (3) implies that the energy of a tree is a monotonically increasing function of any m(T, k) for the study of the energy of trees, we may consider it also for cycle­containing graphs. For such graphsTHE MATCHING ENERGY OF A GRAPH IVAN GUTMAN AND STEPHAN WAGNER Abstract. The energy of a graph G

  11. Embeddings of Cubic Halin Graphs A Surface-by-Surface Inventory

    E-Print Network [OSTI]

    Gross, Jonathan L.

    Embeddings of Cubic Halin Graphs A Surface-by-Surface Inventory Jonathan L. Gross Columbia@cs.columbia.edu; http://www.cs.columbia.edu/gross/. 1 #12;Embeddings of Cubic Halin Graphs: An Inventory 2 1 graph for a 14-vertex tree with 8 leaves. #12;Embeddings of Cubic Halin Graphs: An Inventory 3

  12. ASYMPTOTIC STUDY OF SUBCRITICAL GRAPH CLASSES MICHAEL DRMOTA, ERIC FUSY, MIHYUN KANG, VERONIKA KRAUS

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    ASYMPTOTIC STUDY OF SUBCRITICAL GRAPH CLASSES MICHAEL DRMOTA, ¬īERIC FUSY, MIHYUN KANG, VERONIKA from the so-called "subcritical" graph classes, which include the classes of cacti graphs, outerplanar graphs chosen from subcritical classes. We show that the number gn/n! (resp. gn) of labelled (resp

  13. Geodesic Distance in Planar Graphs: An Integrable Approach

    E-Print Network [OSTI]

    P. Di Francesco

    2005-06-27T23:59:59.000Z

    We discuss the enumeration of planar graphs using bijections with suitably decorated trees, which allow for keeping track of the geodesic distances between faces of the graph. The corresponding generating functions obey non-linear recursion relations on the geodesic distance. These are solved by use of stationary multi-soliton tau-functions of suitable reductions of the KP hierarchy. We obtain a unified formulation of the (multi-) critical continuum limit describing large graphs with marked points at large geodesic distances, and obtain integrable differential equations for the corresponding scaling functions. This provides a continuum formulation of two-dimensional quantum gravity, in terms of the geodesic distance.

  14. The Graph Laplacian and the Dynamics of Complex Networks

    SciTech Connect (OSTI)

    Thulasidasan, Sunil [Los Alamos National Laboratory

    2012-06-11T23:59:59.000Z

    In this talk, we explore the structure of networks from a spectral graph-theoretic perspective by analyzing the properties of the Laplacian matrix associated with the graph induced by a network. We will see how the eigenvalues of the graph Laplacian relate to the underlying network structure and dynamics and provides insight into a phenomenon frequently observed in real world networks - the emergence of collective behavior from purely local interactions seen in the coordinated motion of animals and phase transitions in biological networks, to name a few.

  15. A rigidity result for the graph case of the Penrose inequality

    E-Print Network [OSTI]

    Levi Lopes de Lima; Frederico Gir„o

    2012-06-25T23:59:59.000Z

    In this note we prove a global rigidity result for asymptotically flat, scalar flat Euclidean hypersurfaces with a minimal horizon lying in a hyperplane, under a natural ellipticity condition. As a consequence we obtain, in the context of the Riemannian Penrose conjecture, a local rigidity result for the family of exterior Schwarzschild solutions (viewed as graphs in Euclidean space).

  16. Diamond graphs and super-reflexivity William B. Johnson

    E-Print Network [OSTI]

    Johnson, William B.

    Diamond graphs and super-reflexivity William B. Johnson and Gideon Schechtman Abstract The main results is that dimension reduction a-la Johnson­Lindenstrauss fails in any non super reflexive space

  17. Kron Reduction of Graphs with Applications to Electrical Networks

    E-Print Network [OSTI]

    Dorfler, Florian

    2011-01-01T23:59:59.000Z

    Consider a weighted and undirected graph, possibly with self-loops, and its corresponding Laplacian matrix, possibly augmented with additional diagonal elements corresponding to the self-loops. The Kron reduction of this graph is again a graph whose Laplacian matrix is obtained by the Schur complement of the original Laplacian matrix with respect to a subset of nodes. The Kron reduction process is ubiquitous in classic circuit theory and in related disciplines such as electrical impedance tomography, smart grid monitoring, transient stability assessment in power networks, or analysis and simulation of induction motors and power electronics. More general applications of Kron reduction occur in sparse matrix algorithms, multi-grid solvers, finite--element analysis, and Markov chains. The Schur complement of a Laplacian matrix and related concepts have also been studied under different names and as purely theoretic problems in the literature on linear algebra. In this paper we propose a general graph-theoretic f...

  18. Drawing a Graph in a Hypercube David R. Wood

    E-Print Network [OSTI]

    Wood, David R.

    Drawing a Graph in a Hypercube David R. Wood #3; Departament de Matem#18;atica Aplicada II Universitat Polit#18;ecnica de Catalunya Barcelona, Spain david.wood@upc.edu Submitted: Nov 16, 2004; Accepted

  19. Drawing a Graph in a Hypercube David R. Wood

    E-Print Network [OSTI]

    Wood, David R.

    Drawing a Graph in a Hypercube David R. Wood Departament de Matem`atica Aplicada II Universitat Polit`ecnica de Catalunya Barcelona, Spain david.wood@upc.edu Submitted: Nov 16, 2004; Accepted: Aug 11

  20. Exact Solution of Graph Coloring Problems via Constraint ...

    E-Print Network [OSTI]

    2011-09-21T23:59:59.000Z

    of coloring the vertices of a graph so that adjacent vertices have different ..... in a vector y having always the same order corresponding to that of matrix A rows.

  1. New Lower Bounds on the Stability Number of a Graph

    E-Print Network [OSTI]

    2007-06-27T23:59:59.000Z

    Jun 27, 2007 ... adjacency matrix of G. The complete graph on n vertices is denoted by Kn. ..... We used MATLAB to compute each of the five bounds on each of†...

  2. The Asymmetric Traveling Salesman Problem on Graphs with Bounded Genus

    E-Print Network [OSTI]

    Saberi, Amin

    Saberi Abstract We give a constant factor approximation algorithm for the asymmetric traveling salesman:{shayan, saberi}@stanford.edu. 1 #12;Thin trees were first defined in the graph embedding literature in an attempt

  3. Random Walks with Lookahead in Power Law Random Graphs

    E-Print Network [OSTI]

    Mihail, Milena

    1 Random Walks with Lookahead in Power Law Random Graphs Milena Mihail Amin Saberi Prasad Tetali Georgia Institute of Technology Email: mihail, saberi° @cc.gatech.edu tetali@math.cc.gatech.edu Abstract

  4. Confluence in Data Reduction: Bridging Graph Transformation and Kernelization

    E-Print Network [OSTI]

    Wichmann, Felix

    Ermel Falk H¨uffner Rolf Niedermeier Olga Runge Institut f¨ur Softwaretechnik und Theoretische of critical pair analysis from graph transformation theory, supported by the AGG software tool. These results

  5. Advanced Vulnerability Analysis and Intrusion Detection Through Predictive Attack Graphs

    E-Print Network [OSTI]

    Noel, Steven

    Advanced Vulnerability Analysis and Intrusion Detection Through Predictive Attack Graphs Steven, without considering how they contribute to overall attack risk. Similarly, intrusion alarms are logged threats, complexity of security data, and network growth. Our approach to network defense applies attack

  6. Modeling modern network attacks and countermeasures using attack graphs

    E-Print Network [OSTI]

    Ingols, Kyle W.

    By accurately measuring risk for enterprise networks, attack graphs allow network defenders to understand the most critical threats and select the most effective countermeasures. This paper describes substantial enhancements ...

  7. Fracture and Fragmentation of Simplicial Finite Elements Meshes using Graphs

    SciTech Connect (OSTI)

    Mota, A; Knap, J; Ortiz, M

    2006-10-18T23:59:59.000Z

    An approach for the topological representation of simplicial finite element meshes as graphs is presented. It is shown that by using a graph, the topological changes induced by fracture reduce to a few, local kernel operations. The performance of the graph representation is demonstrated and analyzed, using as reference the 3D fracture algorithm by Pandolfi and Ortiz [22]. It is shown that the graph representation initializes in O(N{sub E}{sup 1.1}) time and fractures in O(N{sub I}{sup 1.0}) time, while the reference implementation requires O(N{sub E}{sup 2.1}) time to initialize and O(N{sub I}{sup 1.9}) time to fracture, where NE is the number of elements in the mesh and N{sub I} is the number of interfaces to fracture.

  8. Local computation algorithms for graphs of non-constant degrees

    E-Print Network [OSTI]

    Yodpinyanee, Anak

    2014-01-01T23:59:59.000Z

    In the model of local computation algorithms (LCAs), we aim to compute the queried part of the output by examining only a small (sublinear) portion of the input. Many recently developed LCAs on graph problems achieve time ...

  9. Parallel Algorithms for Graph Optimization using Tree Decompositions

    SciTech Connect (OSTI)

    Sullivan, Blair D [ORNL; Weerapurage, Dinesh P [ORNL; Groer, Christopher S [ORNL

    2012-06-01T23:59:59.000Z

    Although many $\\cal{NP}$-hard graph optimization problems can be solved in polynomial time on graphs of bounded tree-width, the adoption of these techniques into mainstream scientific computation has been limited due to the high memory requirements of the necessary dynamic programming tables and excessive runtimes of sequential implementations. This work addresses both challenges by proposing a set of new parallel algorithms for all steps of a tree decomposition-based approach to solve the maximum weighted independent set problem. A hybrid OpenMP/MPI implementation includes a highly scalable parallel dynamic programming algorithm leveraging the MADNESS task-based runtime, and computational results demonstrate scaling. This work enables a significant expansion of the scale of graphs on which exact solutions to maximum weighted independent set can be obtained, and forms a framework for solving additional graph optimization problems with similar techniques.

  10. Min-Max Theorems Related to Geometric Representationsof Graphs ...

    E-Print Network [OSTI]

    Marcel K. de Carli Silva and Levent Tuncel

    2011-08-06T23:59:59.000Z

    Oct 27, 2010 ... 1. Introduction. Geometric representations of graphs is a beautiful area where combina- ..... We shall use the following construction to get hypersphere ...... This is not surprising, as SDP duality theory is more complex than LP.

  11. Technology Portfolio Planning by Weighted Graph Analysis of System Architectures

    E-Print Network [OSTI]

    de Weck, Olivier L.

    Technology Portfolio Planning by Weighted Graph Analysis of System Architectures Peter Davison and Bruce Cameron Massachusetts Institute of Technology, Cambridge, MA 02139 Edward F. Crawley Skolkovo Institute of Science and Technology, Skolkovo 143025, Russia Abstract5 Many systems undergo significant

  12. Ranking Outlier Nodes in Subspaces of Attributed Graphs

    E-Print Network [OSTI]

    Antwerpen, Universiteit

    . Our graph outlier ranking (GOutRank) introduces scoring functions based on these selected subgraphs by looking at the most promising objects first. They 1http://www.ipd.kit.edu/~muellere/GOutRank/ allow users

  13. How are Feynman graphs resumed by the Loop Vertex Expansion?

    E-Print Network [OSTI]

    Vincent Rivasseau; Zhituo Wang

    2010-06-23T23:59:59.000Z

    The purpose of this short letter is to clarify which set of pieces of Feynman graphs are resummed in a Loop Vertex Expansion, and to formulate a conjecture on the $\\phi^4$ theory in non-integer dimension.

  14. Decoding linear codes via optimization and graph-based techniques

    E-Print Network [OSTI]

    Taghavi, Mohammad H.

    2008-01-01T23:59:59.000Z

    2.2.1 Linear Codes on1.1.2 Graph-Based Codes 1.2 Dissertation Overview . . .versus the length of the code for (3,6)-regular LDPC codes (

  15. MacWilliams identities for codes on graphs

    E-Print Network [OSTI]

    Forney, G. David, Jr.

    The MacWilliams identity for linear time-invariant convolutional codes that has recently been found by Gluesing-Luerssen and Schneider is proved concisely, and generalized to arbitrary group codes on graphs. A similar ...

  16. On the limiting absorption principle and spectra of quantum graphs

    E-Print Network [OSTI]

    Beng-Seong Ong

    2005-10-10T23:59:59.000Z

    The main result of the article is validity of the limiting absorption principle and thus absence of the singular continuous spectrum for compact quantum graphs with several infinite leads attached. The technique used involves Dirichlet-to-Neumann operators.

  17. The Branching of Graphs in 2-d Quantum Gravity

    E-Print Network [OSTI]

    M. G. Harris

    1996-07-16T23:59:59.000Z

    The branching ratio is calculated for three different models of 2d gravity, using dynamical planar phi-cubed graphs. These models are pure gravity, the D=-2 Gaussian model coupled to gravity and the single spin Ising model coupled to gravity. The ratio gives a measure of how branched the graphs dominating the partition function are. Hence it can be used to estimate the location of the branched polymer phase for the multiple Ising model coupled to 2d gravity.

  18. Discrete Mathematics and Theoretical Computer Science DMTCS vol. 11:2, 2009, 149160 Spectral characterizations of sun graphs and

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    characterizations of sun graphs and broken sun graphs Romain Boulet Institut de Math¬īematiques de Toulouse by their spectrum by considering some unicyclic graphs. An odd (resp. even) sun is a graph obtained by appending a pendant vertex to each vertex of an odd (resp. even) cycle. A broken sun is a graph obtained by deleting

  19. Multicoloured Random Graphs: The Random Dynamics Program

    E-Print Network [OSTI]

    Sam Tarzi

    2014-07-15T23:59:59.000Z

    The Random Dynamics program is a proposal to explain the origin of all symmetries, including Lorentz and gauge invariance without appeal to any fundamental invariance of the laws of nature, and to derive the known physical laws in such a way as to be almost unavoidable. C. D. Froggatt and H. B. Nielsen proposed in their book Origin of Symmetries, that symmetries and physical laws should arise naturally from some essentially random dynamics rather than being postulated to be exact. The most useful assumption of the program that can be made about the fundamental laws is taken to be that they are random and then to see how known physics like mechanics and relativity follow from them. It is believed that almost any model of these regularities would appear in some limit for example as energies become small. Almost all theories or models at the fundamental level could then explain known physics. We suggest how using the formalism and properties of random graphs might be useful in developing the theory, and point towards directions in which it can be more fully extended in future work.

  20. Pauli graph and finite projective lines/geometries

    E-Print Network [OSTI]

    Michel R. P. Planat; Metod Saniga

    2007-03-16T23:59:59.000Z

    The commutation relations between the generalized Pauli operators of N-qudits (i. e., N p-level quantum systems), and the structure of their maximal sets of commuting bases, follow a nice graph theoretical/geometrical pattern. One may identify vertices/points with the operators so that edges/lines join commuting pairs of them to form the so-called Pauli graph P_{p^N} . As per two-qubits (p = 2, N = 2) all basic properties and partitionings of this graph are embodied in the geometry of the symplectic generalized quadrangle of order two, W(2). The structure of the two-qutrit (p = 3, N = 2) graph is more involved; here it turns out more convenient to deal with its dual in order to see all the parallels with the two-qubit case and its surmised relation with the geometry of generalized quadrangle Q(4, 3), the dual of W(3). Finally, the generalized adjacency graph for multiple (N > 3) qubits/qutrits is shown to follow from symplectic polar spaces of order two/three. The relevance of these mathematical concepts to mutually unbiased bases and to quantum entanglement is also highlighted in some detail.

  1. Kron Reduction of Graphs with Applications to Electrical Networks

    E-Print Network [OSTI]

    Florian Dorfler; Francesco Bullo

    2011-02-15T23:59:59.000Z

    Consider a weighted and undirected graph, possibly with self-loops, and its corresponding Laplacian matrix, possibly augmented with additional diagonal elements corresponding to the self-loops. The Kron reduction of this graph is again a graph whose Laplacian matrix is obtained by the Schur complement of the original Laplacian matrix with respect to a subset of nodes. The Kron reduction process is ubiquitous in classic circuit theory and in related disciplines such as electrical impedance tomography, smart grid monitoring, transient stability assessment in power networks, or analysis and simulation of induction motors and power electronics. More general applications of Kron reduction occur in sparse matrix algorithms, multi-grid solvers, finite--element analysis, and Markov chains. The Schur complement of a Laplacian matrix and related concepts have also been studied under different names and as purely theoretic problems in the literature on linear algebra. In this paper we propose a general graph-theoretic framework for Kron reduction that leads to novel and deep insights both on the mathematical and the physical side. We show the applicability of our framework to various practical problem setups arising in engineering applications and computation. Furthermore, we provide a comprehensive and detailed graph-theoretic analysis of the Kron reduction process encompassing topological, algebraic, spectral, resistive, and sensitivity analyses. Throughout our theoretic elaborations we especially emphasize the practical applicability of our results.

  2. A graph-based system for network-vulnerability analysis

    SciTech Connect (OSTI)

    Swiler, L.P.; Phillips, C.

    1998-06-01T23:59:59.000Z

    This paper presents a graph-based approach to network vulnerability analysis. The method is flexible, allowing analysis of attacks from both outside and inside the network. It can analyze risks to a specific network asset, or examine the universe of possible consequences following a successful attack. The graph-based tool can identify the set of attack paths that have a high probability of success (or a low effort cost) for the attacker. The system could be used to test the effectiveness of making configuration changes, implementing an intrusion detection system, etc. The analysis system requires as input a database of common attacks, broken into atomic steps, specific network configuration and topology information, and an attacker profile. The attack information is matched with the network configuration information and an attacker profile to create a superset attack graph. Nodes identify a stage of attack, for example the class of machines the attacker has accessed and the user privilege level he or she has compromised. The arcs in the attack graph represent attacks or stages of attacks. By assigning probabilities of success on the arcs or costs representing level-of-effort for the attacker, various graph algorithms such as shortest-path algorithms can identify the attack paths with the highest probability of success.

  3. Quantum ergodicity for graphs related to interval maps

    E-Print Network [OSTI]

    G. Berkolaiko; J. P. Keating; U. Smilansky

    2006-07-07T23:59:59.000Z

    We prove quantum ergodicity for a family of graphs that are obtained from ergodic one-dimensional maps of an interval using a procedure introduced by Pakonski et al (J. Phys. A, v. 34, 9303-9317 (2001)). As observables we take the L^2 functions on the interval. The proof is based on the periodic orbit expansion of a majorant of the quantum variance. Specifically, given a one-dimensional, Lebesgue-measure-preserving map of an interval, we consider an increasingly refined sequence of partitions of the interval. To this sequence we associate a sequence of graphs, whose directed edges correspond to elements of the partitions and on which the classical dynamics approximates the Perron-Frobenius operator corresponding to the map. We show that, except possibly for subsequences of density 0, the eigenstates of the quantum graphs equidistribute in the limit of large graphs. For a smaller class of observables we also show that the Egorov property, a correspondence between classical and quantum evolution in the semiclassical limit, holds for the quantum graphs in question.

  4. Mining Large Heterogeneous Graphs using Cray s Urika

    SciTech Connect (OSTI)

    Sukumar, Sreenivas R [ORNL] [ORNL; Bond, Nathaniel A [ORNL] [ORNL

    2013-01-01T23:59:59.000Z

    Pattern discovery and predictive modeling from seemingly related Big Data represented as massive, ad-hoc, heterogeneous networks (e.g., extremely large graphs with complex, possibly unknown structure) is an outstanding problem in many application domains. To address this problem, we are designing graph-mining algorithms capable of discovering relationship-patterns from such data and using those discovered patterns as features for classification and predictive modeling. Specifically, we are: (i) exploring statistical properties, mechanics and generative models of behavior patterns in heterogeneous information networks, (ii) developing novel, automated and scalable graph-pattern discovery algorithms and (iii) applying our relationship-analytics (data science + network science) expertise to domains spanning healthcare to homeland security.

  5. Semi-classical measures on Quantum graphs and the Gau map of the determinant manifold

    E-Print Network [OSTI]

    Recanati, Catherine

    believed that QE does not hold in general for a FIXED quantum graph. This is proved for star graphs in [BKW to what people do in several papers like [BG00, BKW04, BW08, Ba12, BB13]. Let

  6. Structural Testing: An Introduction Flow Graphs Path Testing Conclusions Path Testing

    E-Print Network [OSTI]

    Mousavi, Mohammad

    Structural Testing: An Introduction Flow Graphs Path Testing Conclusions Path Testing Mohammad Mousavi Eindhoven University of Technology, The Netherlands Software Testing, 2013 Mousavi: Path Testing #12;Structural Testing: An Introduction Flow Graphs Path Testing Conclusions Outline Structural

  7. Structural Testing: An Introduction Flow Graphs Path Testing Conclusions Path Testing

    E-Print Network [OSTI]

    Mousavi, Mohammad

    Structural Testing: An Introduction Flow Graphs Path Testing Conclusions Path Testing Mohammad Mousavi Eindhoven University of Technology, The Netherlands Software Testing, 2012 Mousavi: Path Testing #12;Structural Testing: An Introduction Flow Graphs Path Testing Conclusions Outline Structural

  8. Random intersection graphs and their applications in security, wireless communication, and social networks

    E-Print Network [OSTI]

    Zhao, Jun; Gligor, Virgil

    2015-01-01T23:59:59.000Z

    Random intersection graphs have received much interest and been used in diverse applications. They are naturally induced in modeling secure sensor networks under random key predistribution schemes, as well as in modeling the topologies of social networks including common-interest networks, collaboration networks, and actor networks. Simply put, a random intersection graph is constructed by assigning each node a set of items in some random manner and then putting an edge between any two nodes that share a certain number of items. Broadly speaking, our work is about analyzing random intersection graphs, and models generated by composing it with other random graph models including random geometric graphs and Erd\\H{o}s-R\\'enyi graphs. These compositional models are introduced to capture the characteristics of various complex natural or man-made networks more accurately than the existing models in the literature. For random intersection graphs and their compositions with other random graphs, we study properties su...

  9. Math 497E/564 Graph Theory Winter 2012 Instructor Amites Sarkar

    E-Print Network [OSTI]

    Sarkar, Amites

    Math 497E/564 Graph Theory Winter 2012 Instructor Amites Sarkar Text Modern Graph Theory B, in 216 Bond Hall. My phone number is 650 7569 and my e-mail is amites.sarkar@wwu.edu #12;

  10. Vacuum energy, spectral determinant and heat kernel asymptotics of graph Laplacians with general vertex matching conditions

    E-Print Network [OSTI]

    J. M. Harrison; K. Kirsten

    2010-03-16T23:59:59.000Z

    We consider Laplace operators on metric graphs, networks of one-dimensional line segments (bonds), with matching conditions at the vertices that make the operator self-adjoint. Such quantum graphs provide a simple model of quantum mechanics in a classically chaotic system with multiple scales corresponding to the lengths of the bonds. For graph Laplacians we briefly report results for the spectral determinant, vacuum energy and heat kernel asymptotics of general graphs in terms of the vertex matching conditions.

  11. Highly Connected Random Geometric Graphs Paul Balister #+ Bela Bollobas +# Amites Sarkar + Mark Walters #

    E-Print Network [OSTI]

    Banaji,. Murad

    Highly Connected Random Geometric Graphs Paul Balister #+ B‚??ela Bollob‚??as +#¬ß Amites Sarkar +¬∂ Mark

  12. Bounds for mixing time of quantum walks on finite graphs

    E-Print Network [OSTI]

    Vladislav Kargin

    2010-07-21T23:59:59.000Z

    Several inequalities are proved for the mixing time of discrete-time quantum walks on finite graphs. The mixing time is defined differently than in Aharonov, Ambainis, Kempe and Vazirani (2001) and it is found that for particular examples of walks on a cycle, a hypercube and a complete graph, quantum walks provide no speed-up in mixing over the classical counterparts. In addition, non-unitary quantum walks (i.e., walks with decoherence) are considered and a criterion for their convergence to the unique stationary distribution is derived.

  13. Bifurcations of mutually coupled equations in random graphs

    E-Print Network [OSTI]

    Eduardo Garibaldi; Tiago Pereira

    2014-09-19T23:59:59.000Z

    We study the behavior of solutions of mutually coupled equations in heterogeneous random graphs. Heterogeneity means that some equations receive many inputs whereas most of the equations are given only with a few connections. Starting from a situation where the isolated equations are unstable, we prove that a heterogeneous interaction structure leads to the appearance of stable subspaces of solutions. Moreover, we show that, for certain classes of heterogeneous networks, increasing the strength of interaction leads to a cascade of bifurcations in which the dimension of the stable subspace of solutions increases. We explicitly determine the bifurcation scenario in terms of the graph structure.

  14. Groups generated by bounded automata and their schreier graphs

    E-Print Network [OSTI]

    Bondarenko, Ievgen

    2008-10-10T23:59:59.000Z

    on levels of automaton groups can be constructed by an iterative procedure of inflation of graphs. This was used to associate a piecewise linear map of the form fK(v) = minA?KAv, where K is a finite set of nonnegative matrices, with every bounded automaton... and minimal growth of the components of f(n)K (v). We prove that the growth exponent of diameters of the Schreier graphs is equal to ?max and the orbital contracting coefficient of the group is equal to 1? min . We prove that the simple random walks on orbital...

  15. Some Remarks on Cycles in Graphs and Digraphs \\Lambda Martin Loebl

    E-Print Network [OSTI]

    Loebl, Martin

    Some Remarks on Cycles in Graphs and Digraphs \\Lambda Martin Loebl Department of Applied, Chile mmatamal@dim.uchile.cl Abstract We survey several recent results on cycles of graphs and directed graphs of the following form: 'Does there exist a set of cycles with a property P that generates all

  16. EVEN CYCLE DECOMPOSITIONS OF GRAPHS WITH NO ODD-K4-MINOR

    E-Print Network [OSTI]

    Kim, Yong Jung

    EVEN CYCLE DECOMPOSITIONS OF GRAPHS WITH NO ODD-K4-MINOR TONY HUYNH, SANG-IL OUM, AND MARYAM VERDIAN-RIZI Abstract. An even cycle decomposition of a graph G is a partition of E(G) into cycles of even length. Evidently, every Eulerian bipartite graph has an even cycle decomposition. Seymour [circuits

  17. Improved bounds and algorithms for graph cuts and network reliability David G. Harris

    E-Print Network [OSTI]

    Srinivasan, Aravind

    Improved bounds and algorithms for graph cuts and network reliability David G. Harris Aravind, the graphs we deal with will be multi-graphs with no self-loops. We define R(p), the reliability polyno- mial there is no currently known algorithm for estimating R(p), the complementary probability U(p) = 1 - R(p), which we

  18. CLAW-FREE 3-CONNECTED P11-FREE GRAPHS ARE HAMILTONIAN

    E-Print Network [OSTI]

    Pfender, Florian

    CLAW-FREE 3-CONNECTED P11-FREE GRAPHS ARE HAMILTONIAN TOMASZ LUCZAK AND FLORIAN PFENDER Abstract. We show that every 3-connected claw-free graph which contains no induced copy of P11 is hamiltonian. Since there ex- ist non-hamiltonian 3-connected claw-free graphs without induced copies of P12

  19. The evolution of helping and harming on graphs: the return of the inclusive fitness effect

    E-Print Network [OSTI]

    Alvarez, Nadir

    The evolution of helping and harming on graphs: the return of the inclusive fitness effect L relatedness between individuals promotes helping behaviour, evolu- tionary graph theory emphasizes., 2006; Ohtsuki & Nowak, 2006). Evolutionary graph theory models allow the effect of space on helping

  20. Between automation and exploration: SAS graphing techniques for visualization of survey data

    E-Print Network [OSTI]

    Yu, Alex

    Between automation and exploration: SAS graphing techniques for visualization of survey data Chong of survey data. There is always a tension between automation and exploration. Automation is a common to automate the graphing processes via SAS/Macros and SAS/Graph. However, hidden patterns of the data may

  1. Protection of a Graph EJ Cockayne y , PJP Grobler z , WR Grundlingh z ,

    E-Print Network [OSTI]

    van Vuuren, Jan H.

    four strategies, i.e. properties of such functions under which the entire graph may be deemed protected of guards required to protect the graph under the various strategies, are stud- ied. Exact values or boundsProtection of a Graph #3; EJ Cockayne y , PJP Grobler z , WR Grundlingh z , J Munganga √? & JH van

  2. Graph Databases for Large-Scale Healthcare Systems: A Framework for Efficient Data Management and Data Services

    SciTech Connect (OSTI)

    Park, Yubin [University of Texas at Austin] [University of Texas at Austin; Shankar, Mallikarjun [ORNL] [ORNL; Park, Byung H [ORNL] [ORNL; Ghosh, Dr. Joydeep [University of Texas at Austin] [University of Texas at Austin

    2014-01-01T23:59:59.000Z

    Designing a database system for both efficient data management and data services has been one of the enduring challenges in the healthcare domain. In many healthcare systems, data services and data management are often viewed as two orthogonal tasks; data services refer to retrieval and analytic queries such as search, joins, statistical data extraction, and simple data mining algorithms, while data management refers to building error-tolerant and non-redundant database systems. The gap between service and management has resulted in rigid database systems and schemas that do not support effective analytics. We compose a rich graph structure from an abstracted healthcare RDBMS to illustrate how we can fill this gap in practice. We show how a healthcare graph can be automatically constructed from a normalized relational database using the proposed 3NF Equivalent Graph (3EG) transformation.We discuss a set of real world graph queries such as finding self-referrals, shared providers, and collaborative filtering, and evaluate their performance over a relational database and its 3EG-transformed graph. Experimental results show that the graph representation serves as multiple de-normalized tables, thus reducing complexity in a database and enhancing data accessibility of users. Based on this finding, we propose an ensemble framework of databases for healthcare applications.

  3. MATLAB Tutorial Getting Started with Calculations, Graphing and Programming

    E-Print Network [OSTI]

    Weinberger, Hans

    MATLAB Tutorial Getting Started with Calculations, Graphing and Programming Nicholas R. Kirchner University of Minnesota Thursday, August 30, 2012 #12;Outline 1 MATLAB installation NRK (University of Minnesota) MATLAB 2012.08.30 2 / 28 #12;Outline 1 MATLAB installation 2 The MATLAB UI NRK (University

  4. Analyzing Gene Relationships for Down Syndrome with Labeled Transition Graphs

    E-Print Network [OSTI]

    Brigham Young University

    Analyzing Gene Relationships for Down Syndrome with Labeled Transition Graphs Neha Rungta, Hyrum changes in gene expres- sion and physical characteristics associated with Down syndrome is not well understood. Chromosome 21 genes interact with non- chromosome 21 genes to produce Down syndrome

  5. Structured Region Graphs: Morphing EP into GBP Max Welling

    E-Print Network [OSTI]

    Welling, Max

    Structured Region Graphs: Morphing EP into GBP Max Welling Dept. of Computer Science UC Irvine@eecs.berkeley.edu Abstract GBP and EP are two successful algo­ rithms for approximate probabilistic infer­ ence, which on these structures allow conversion between EP and GBP free ener­ gies. Thus it is revealed that all EP ap

  6. Structured Region Graphs: Morphing EP into GBP Max Welling

    E-Print Network [OSTI]

    Welling, Max

    Structured Region Graphs: Morphing EP into GBP Max Welling Dept. of Computer Science UC Irvine@eecs.berkeley.edu Abstract GBP and EP are two successful algo- rithms for approximate probabilistic infer- ence, which on these structures allow conversion between EP and GBP free ener- gies. Thus it is revealed that all EP ap

  7. Kron Reduction of Graphs with Applications to Electrical Networks

    E-Print Network [OSTI]

    Bullo, Francesco

    1 Kron Reduction of Graphs with Applications to Electrical Networks Florian D¨orfler Francesco work supported by NSF grants IIS- 0904501 and CPS-1135819. Florian D¨orfler and Francesco Bullo Barbara, CA 93106, {dorfler, bullo}@engineering.ucsb.edu we consider the circuit naturally associated

  8. Brain Mapping Using Topology Graphs Obtained by Surface Segmentation

    E-Print Network [OSTI]

    Linsen, Lars

    Brain Mapping Using Topology Graphs Obtained by Surface Segmentation Fabien Vivodtzev1 , Lars@ucdavis.edu Summary. Brain mapping is a technique used to alleviate the tedious and time- consuming process of annotating brains by mapping existing annotations from brain atlases to individual brains. We introduce

  9. Spectral Decision Diagrams Using Graph Transformations Mitchell Thornton Rolf Drechsler

    E-Print Network [OSTI]

    Thornton, Mitchell

    Spectral Decision Diagrams Using Graph Transformations #3; Mitchell Thornton Rolf Drechsler Department of Electrical and Computer Engineering Siemens AG Mississippi State University Corporate Technology Mississippi State, MS 39762 81730 Munich, Germany mitch@ece.msstate.edu rolf.drechsler@mchp.siemens

  10. Mining Large Graphs And Streams Using Matrix And Tensor Tools

    E-Print Network [OSTI]

    Kolda, Tamara G.

    RESULTS The graphs at right show overall variability distribution estimated for the Pentium D 800 where a core no longer works properly. In the Sun T1 Niagara cores this is done with a built-in- self processors we record the temperature at which the failure occurred and adjust to the frequencies

  11. Optimizing Path Query Performance: Graph Clustering Strategies \\Lambda

    E-Print Network [OSTI]

    .J. Watson Labs ywh@us.ibm.com Ning Jing z Changsha Institute of Technology jning@eecs.umich.edu Elke A because it does not incur any run­time cost, requires no auxiliary data structures, and is complimentary evaluation of the performance of these graph clustering techniques using an actual city road network as well

  12. An Interchange File Format for Graphs Michael Himsolt

    E-Print Network [OSTI]

    Pentus, Mati

    graphical information. It is designed as an extendible format and provides facilities such that other be as flexible and extensible as possible. Other programs should be able to write graph files with low overhead Ascii). Since end of line is encoded differ­ ently on different platform, we choose not to use end­of­line

  13. Hamilton cycles in graphs and hypergraphs: an extremal perspective

    E-Print Network [OSTI]

    Osthus, Deryk

    Hamilton cycles in graphs and hypergraphs: an extremal perspective Abstract. As one of the most fundamental and well-known NP-complete problems, the Hamilton cycle problem has been the subject of intensive and the study of Hamilton cycles in hypergraphs. We survey these developments and highlight open problems

  14. HAMILTON CYCLES IN GRAPHS AND HYPERGRAPHS: AN EXTREMAL PERSPECTIVE

    E-Print Network [OSTI]

    Osthus, Deryk

    HAMILTON CYCLES IN GRAPHS AND HYPERGRAPHS: AN EXTREMAL PERSPECTIVE DANIELA K¨UHN AND DERYK OSTHUS Abstract. As one of the most fundamental and well-known NP-complete problems, the Hamilton cycle problem emerged, such as resilience, robustness and the study of Hamilton cycles in hypergraphs. We survey

  15. HAMILTON CYCLES IN GRAPHS AND HYPERGRAPHS: AN EXTREMAL PERSPECTIVE

    E-Print Network [OSTI]

    Osthus, Deryk

    HAMILTON CYCLES IN GRAPHS AND HYPERGRAPHS: AN EXTREMAL PERSPECTIVE DANIELA K¨UHN AND DERYK OSTHUS Abstract. As one of the most fundamental and well-known NP-complete prob- lems, the Hamilton cycle problem emerged, such as resilience, robustness and the study of Hamilton cycles in hypergraphs. We survey

  16. Compatible Hamilton cycles in random graphs Michael Krivelevich

    E-Print Network [OSTI]

    Sudakov, Benjamin

    Compatible Hamilton cycles in random graphs Michael Krivelevich Choongbum Lee Benny Sudakov, there exists a properly colored Hamilton cycle. Furthermore, our proof can be easily modified to show, there exists a Hamilton cycle in which all edges have distinct colors (i.e., a rainbow Hamilton cycle). 1

  17. SEISMIC WAVES ESTIMATION AND WAVE FIELD DECOMPOSITION WITH FACTOR GRAPHS

    E-Print Network [OSTI]

    Loeliger, Hans-Andrea

    SEISMIC WAVES ESTIMATION AND WAVE FIELD DECOMPOSITION WITH FACTOR GRAPHS Stefano Maran√≤ Christoph, Dept. Information Technology & Electr. Eng., 8092 Z√ľrich ABSTRACT Physical wave fields are often from sensors of different kinds. In this paper we propose a technique for the analysis of vector wave

  18. Quantitative Analysis of the Full Bitcoin Transaction Graph

    E-Print Network [OSTI]

    Quantitative Analysis of the Full Bitcoin Transaction Graph Dorit Ron and Adi Shamir Department.ron,adi.shamir}@weizmann.ac.il Abstract. The Bitcoin scheme is a rare example of a large scale global payment system in which all and how they spend their bitcoins, the balance of bitcoins they keep in their accounts, and how they move

  19. SMITH INVARIANTS AND DUAL GRADED GRAPHS ALEXANDER MILLER

    E-Print Network [OSTI]

    Weinberger, Hans

    SMITH INVARIANTS AND DUAL GRADED GRAPHS ALEXANDER MILLER Abstract. The aim of this paper the Smith invariants immediately, as the eigenvalues are completely understood [3, 15]. Furthermore, we. Background 1 1.1. Differential posets 1 1.2. Eigenvalues 3 1.3. Smith invariants 3 2. Conjecture for r

  20. Evaluation of Multimodal Graphs for Blind People , STEPHEN BREWSTER

    E-Print Network [OSTI]

    Williamson, John

    sense on people's fingers. Tactile diagrams exist in many forms and they mainly differEvaluation of Multimodal Graphs for Blind People WAI YU 1 , STEPHEN BREWSTER 2 1 Virtual visualisation system and its evaluations. This system is designed to improve blind and visually impaired people

  1. Synchronous Black Hole Search in Directed Graphs Adrian Kosowski

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Synchronous Black Hole Search in Directed Graphs Adrian Kosowski Alfredo Navarra Cristina M called black hole nodes, and once a robot enters in one of them, it is destroyed. The goal is to find supported by the Italian CNR Short-Term Mobility Program. A. Kosowski was supported Polish Ministry Grant N

  2. WRIGHT'S CONSTANTS IN GRAPH ENUMERATION AND BROWNIAN EXCURSION AREA

    E-Print Network [OSTI]

    Janson, Svante

    WRIGHT'S CONSTANTS IN GRAPH ENUMERATION AND BROWNIAN EXCURSION AREA SVANTE JANSON Abstract - 1) = n n-2 for every n # 1. Wright [19] proved that for any fixed k # -1, we have the analoguous) Note the equivalent recursion formula # k+1 = 3k + 2 2 # k + k # j=0 # j # k-j , k # -1. (4) Wright

  3. WRIGHT'S CONSTANTS IN GRAPH ENUMERATION AND BROWNIAN EXCURSION AREA

    E-Print Network [OSTI]

    Janson, Svante

    WRIGHT'S CONSTANTS IN GRAPH ENUMERATION AND BROWNIAN EXCURSION AREA SVANTE JANSON Abstract n 1. Wright [19] proved that for any fixed k -1, we have the analoguous asymptotic formula C(n, n-j, k -1. (4) Wright gives in the later paper [20] the same result in the form k = 2(1-5k)/23k1/2(k - 1

  4. A graph-based network-vulnerability analysis system

    SciTech Connect (OSTI)

    Swiler, L.P.; Phillips, C.; Gaylor, T.

    1998-05-03T23:59:59.000Z

    This paper presents a graph based approach to network vulnerability analysis. The method is flexible, allowing analysis of attacks from both outside and inside the network. It can analyze risks to a specific network asset, or examine the universe of possible consequences following a successful attack. The analysis system requires as input a database of common attacks, broken into atomic steps, specific network configuration and topology information, and an attacker profile. The attack information is matched with the network configuration information and an attacker profile to create a superset attack graph. Nodes identify a stage of attack, for example the class of machines the attacker has accessed and the user privilege level he or she has compromised. The arcs in the attack graph represent attacks or stages of attacks. By assigning probabilities of success on the arcs or costs representing level of effort for the attacker, various graph algorithms such as shortest path algorithms can identify the attack paths with the highest probability of success.

  5. A graph-based network-vulnerability analysis system

    SciTech Connect (OSTI)

    Swiler, L.P.; Phillips, C. [Sandia National Labs., Albuquerque, NM (United States); Gaylor, T. [3M, Austin, TX (United States). Visual Systems Div.

    1998-01-01T23:59:59.000Z

    This report presents a graph-based approach to network vulnerability analysis. The method is flexible, allowing analysis of attacks from both outside and inside the network. It can analyze risks to a specific network asset, or examine the universe of possible consequences following a successful attack. The analysis system requires as input a database of common attacks, broken into atomic steps, specific network configuration and topology information, and an attacker profile. The attack information is matched with the network configuration information and an attacker profile to create a superset attack graph. Nodes identify a stage of attack, for example the class of machines the attacker has accessed and the user privilege level he or she has compromised. The arcs in the attack graph represent attacks or stages of attacks. By assigning probabilities of success on the arcs or costs representing level-of-effort for the attacker, various graph algorithms such as shortest-path algorithms can identify the attack paths with the highest probability of success.

  6. Using Visualization Process Graphs to Improve Visualization Exploration

    E-Print Network [OSTI]

    Jankun-Kelly, T. J.

    Using Visualization Process Graphs to Improve Visualization Exploration T. J. Jankun-Kelly1 University, MS 39762, USA. Email: tjk@acm.org Abstract. Visualization exploration is an iterative process, redundant exploration was quickly identified and eliminated. 1 Introduction During the visualization process

  7. Graphs, Rewriting and Pathway Reconstruction for Rule-Based Models

    E-Print Network [OSTI]

    Fontana, Walter

    simulation of systems represented by rule- based models. This is founded on a new, clean, graph on Foundations of Software Technology and Theoretical Computer Science (FSTTCS 2012). Editors: D. D'Souza, J ¬≠ Leibniz-Zentrum f√ľr Informatik, Dagstuhl Publishing, Germany #12;Danos et al. 277 illuminates choices made

  8. Approximating the Diameter of Planar Graphs in Near Linear Time

    E-Print Network [OSTI]

    Yuster, Raphael

    common starting vertex. Let Gin (resp. Gout) be the subgraph of G induced by C and all interior (resp. exterior) vertices to C. Let d(Gin, Gout, G) denote the largest distance in the graph G between a marked vertex in V (Gin) and a marked vertex in V (Gout). In the beginning, all vertices of G are marked and we

  9. A Simple Approach to Abductive Inference using Conceptual Graphs

    E-Print Network [OSTI]

    Pagnucco, Maurice

    A Simple Approach to Abductive Inference using Conceptual Graphs Maurice Pagnucco Knowledge Systems, Australia. email: morri@cs.su.oz.au fax : +61­2­692­3838 Abstract Abductive reasoning (or simply abduction) is a form of logical in­ ference that aims to derive plausible explanations for data. The term ``abduction

  10. Concept generation of dynamic systems using bond graphs

    E-Print Network [OSTI]

    Krishnan, S

    1990-01-01T23:59:59.000Z

    REPRESENTATIONS OF IMMITTANCES . . . Immittance synthesis in design Conventional immit tance synthesis techniques by Foster and Cauer Immittance synthesis with bond graphs . . . . . . . . . . . . . Example - Synthesis of two frequency absorber... . . . . . . . . . 35 . 35 . 38 . . . . . . 40 . . . . . . 49 TABLE OF CONTENTS (Continued) CHAPTER Page V PHYSICAL REPRESENTATIONS OF TRANSFER FUNCTIONS Transfer function synthesis in design . . . . . . . . . . . General procedure Conditions for passive...

  11. The average number of distinct sites visited by a random walker on random graphs

    E-Print Network [OSTI]

    De Bacco, Caterina; Sollich, Peter

    2015-01-01T23:59:59.000Z

    We study the linear large $n$ behavior of the average number of distinct sites $S(n)$ visited by a random walker after $n$ steps on a large random graph. An expression for the graph topology dependent prefactor $B$ in $S(n) = Bn$ is proposed. We use generating function techniques to relate this prefactor to the graph adjacency matrix and then devise message-passing equations to calculate its value. Numerical simulations are performed to evaluate the agreement between the message passing predictions and random walk simulations on random graphs. Scaling with system size and average graph connectivity are also analysed.

  12. Multi-view kernel construction

    E-Print Network [OSTI]

    Sa, Virginia R.; Gallagher, Patrick W.; Lewis, Joshua M.; Malave, Vicente L.

    2010-01-01T23:59:59.000Z

    5157-z Multi-view kernel construction Virginia R. de Sa ∑multiple different graph construction algorithms. The Ng et

  13. LDRD final report : first application of geospatial semantic graphs to SAR image data.

    SciTech Connect (OSTI)

    Brost, Randolph C.; McLendon, William Clarence,

    2013-01-01T23:59:59.000Z

    Modeling geospatial information with semantic graphs enables search for sites of interest based on relationships between features, without requiring strong a priori models of feature shape or other intrinsic properties. Geospatial semantic graphs can be constructed from raw sensor data with suitable preprocessing to obtain a discretized representation. This report describes initial work toward extending geospatial semantic graphs to include temporal information, and initial results applying semantic graph techniques to SAR image data. We describe an efficient graph structure that includes geospatial and temporal information, which is designed to support simultaneous spatial and temporal search queries. We also report a preliminary implementation of feature recognition, semantic graph modeling, and graph search based on input SAR data. The report concludes with lessons learned and suggestions for future improvements.

  14. Quantitative Analysis of the Full Bitcoin Transaction Graph

    E-Print Network [OSTI]

    Dorit Ron; Adi Shamir

    Abstract. The Bitcoin scheme is a rare example of a large scale global payment system in which all the transactions are publicly accessible (but in an anonymous way). We downloaded the full history of this scheme, and analyzed many statistical properties of its associated transaction graph. In this paper we answer for the first time a variety of interesting questions about the typical behavior of users, how they acquire and how they spend their bitcoins, the balance of bitcoins they keep in their accounts, and how they move bitcoins between their various accounts in order to better protect their privacy. In addition, we isolated all the large transactions in the system, and discovered that almost all of them are closely related to a single large transaction that took place in November 2010, even though the associated users apparently tried to hide this fact with many strange looking long chains and fork-merge structures in the transaction graph.

  15. A graph-separation theorem for quantum causal models

    E-Print Network [OSTI]

    Jacques Pienaar; Caslav Brukner

    2014-10-31T23:59:59.000Z

    A causal model is an abstract representation of a physical system as a directed acyclic graph (DAG), where the statistical dependencies are encoded using a graphical criterion called `d-separation'. Recent work by Wood & Spekkens shows that causal models cannot, in general, provide a faithful representation of quantum systems. Since d-separation encodes a form of Reichenbach's Common Cause Principle (RCCP), whose validity is questionable in quantum mechanics, we propose a generalised graph separation rule that does not assume the RCCP. We prove that the new rule faithfully captures the statistical dependencies between observables in a quantum network, encoded as a DAG, and is consistent with d-separation in a classical limit. We note that the resulting model is still unable to give a faithful representation of correlations stronger than quantum mechanics, such as the Popescu-Rorlich box.

  16. Spectral properties of microwave graphs with local absorption

    E-Print Network [OSTI]

    M. Allgaier; S. Gehler; S. Barkhofen; H. -J. StŲckmann; U. Kuhl

    2014-03-30T23:59:59.000Z

    The influence of absorption on the spectra of microwave graphs has been studied experimentally. The microwave networks were made up of coaxial cables and T junctions. First, absorption was introduced by attaching a 50 Ohm load to an additional vertex for graphs with and without time-reversal symmetry. The resulting level-spacing distributions were compared with a generalization of the Wigner surmise in the presence of open channels proposed recently by Poli et al. [Phys. Rev. Lett. 108, 174101 (2012)]. Good agreement was found using an effective coupling parameter. Second, absorption was introduced along one individual bond via a variable microwave attenuator, and the influence of absorption on the length spectrum was studied. The peak heights in the length spectra corresponding to orbits avoiding the absorber were found to be independent of the attenuation, whereas, the heights of the peaks belonging to orbits passing the absorber once or twice showed the expected decrease with increasing attenuation.

  17. Judicious partitions of graphs Bela Bollobas and Alexander Scott

    E-Print Network [OSTI]

    Scott, Alexander Alexander

    , and for any graph G, there is a partition V (G) = k i=1 Vi such that e(G[Vi]) e(G)/ k+1 2 for i = 1 demand 1 #12;that e(G[Vi]) be fairly close to e(G)/k2 , for i = 1, . . . , k, and that e(Vi, Vj) be fairly close to 2e(G)/k2 , for 1 i

  18. A Spatiotemporal Graph Model for Rainfall Event Identification and Representation

    E-Print Network [OSTI]

    Liu, Weibo

    2014-04-21T23:59:59.000Z

    of a storm ? The spread of a wildfire ? Other dynamic geographic phenomena from time series of snapshot datasets 3Research Objectives Identify the whole lifecycle of rainstorms from time series of snapshot datasets; Represent and analyze the rainstorms... based on a spatiotemporal graph model; Analyze the spatiotemporal characteristics of rainstorms. Data ? NEXRAD (Next generation Radar) ? Hourly precipitation estimate ? Cover more than 2/3 of the nation Rainstormsí Lifecycle Identification Delineate...

  19. Semi-classical measures on Quantum graphs and the Gau map of the determinant manifold

    E-Print Network [OSTI]

    Boyer, Edmond

    believed that QE does not hold in general for a FIXED quantum graph. In [BKW04], it is proved that QE does

  20. Materials for Math 13900 Bring to class each day: graph paper ...

    E-Print Network [OSTI]

    Roames, Renee S

    2015-01-08T23:59:59.000Z

    Materials for Math 13900. Bring to class each day: graph paper isometric dot paper unlined paper cm ruler. We will also be using: compass small scissors.

  1. A Penrose inequality for asymptotically locally hyperbolic graphs

    E-Print Network [OSTI]

    Levi Lopes de Lima; Frederico Gir„o

    2013-05-14T23:59:59.000Z

    We use the inverse mean curvature flow to prove a sharp Alexandrov-Fenchel-type inequality for a class of hypersurfaces in certain locally hyperbolic manifolds. As an application we derive an optimal Penrose inequality for asymptotically locally hyperbolic graphs in any dimension $n\\geq 3$. When the horizon has the topology of a compact surface of genus at least one, this provides an affirmative answer, for this class of initial data sets, to a question posed by Gibbons, Chru\\'sciel and Simon on the validity of a Penrose-type inequality for black hole solutions carrying a higher genus horizon.

  2. Conclusions and future work We have pointed out the importance of proximity graphs as scaffolds for clustering

    E-Print Network [OSTI]

    Carreira-Perpi√Ī√°n, Miguel √Ā.

    have introduced two new types of proximity graphs based on ensembles of minimum spanning trees, which for non-Euclidean data; study stochastic graphs. 7 Results: dimens. reduction (Isomap) Ellipse, high noise

  3. A tree-decomposed transfer matrix for computing exact Potts model partition functions for arbitrary graphs, with applications to planar graph colourings

    E-Print Network [OSTI]

    Andrea Bedini; Jesper Lykke Jacobsen

    2010-08-06T23:59:59.000Z

    Combining tree decomposition and transfer matrix techniques provides a very general algorithm for computing exact partition functions of statistical models defined on arbitrary graphs. The algorithm is particularly efficient in the case of planar graphs. We illustrate it by computing the Potts model partition functions and chromatic polynomials (the number of proper vertex colourings using Q colours) for large samples of random planar graphs with up to N=100 vertices. In the latter case, our algorithm yields a sub-exponential average running time of ~ exp(1.516 sqrt(N)), a substantial improvement over the exponential running time ~ exp(0.245 N) provided by the hitherto best known algorithm. We study the statistics of chromatic roots of random planar graphs in some detail, comparing the findings with results for finite pieces of a regular lattice.

  4. Actes JFPC 2008 LS(Graph): Un cadre de recherche locale pour des

    E-Print Network [OSTI]

    Deville, Yves

    le diam`etre d'un arbre) parce que ceux-ci sont d¬īej`a impl¬īement¬īes dans LS(Graph). Le program- meur recherche heu- ristiques et metaheuristiques. LS(Graph) est con¬łcu et impl¬īement¬īe en COMET (le code source

  5. Fast solution of NP-hard coloring problems on large random graphs

    E-Print Network [OSTI]

    Bedini, Andrea

    2010-01-01T23:59:59.000Z

    Combining tree decomposition and transfer matrix techniques provides a highly efficient and very general algorithm for computing exact partition functions of statistical models defined on large graphs. We illustrate this by considering the hard problem of computing the exact number of vertex colorings for randomly generated planar graphs with up to N = 100 vertices.

  6. MadGraph/MadEvent 4 SUSY, new models, matching and more!

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    Alwall - MadGraph/MadEvent 4 513 Mar 2007 What is new in MG/ME 4? Web-oriented, modular software banner #12;Johan Alwall - MadGraph/MadEvent 4 713 Mar 2007 Whole chain on web or downloaded and run locally Cards filled on the web or uploaded (reusable) Modular structure ­ easy to interface to other

  7. Possible and necessary winners in voting trees: majority graphs vs. profiles

    E-Print Network [OSTI]

    Rossi, Francesca

    Possible and necessary winners in voting trees: majority graphs vs. profiles Maria Silvia Pini like those of Gibbard and Sattertwhaite demonstrate that, under weak assumptions like an election in voting trees: majority graphs vs. profiles, Maria Silvia Pini, Francesca Rossi, Kristen Brent Venable

  8. A near-optimal approximation algorithm for Asymmetric TSP1 on embedded graphs2

    E-Print Network [OSTI]

    Erickson, Jeff

    algorithm of Oveis Gharan and Saberi [SODA 2011], which applies only to graphs15 with orientable genus g and Saberi [11] described a polynomial-time9 O( g log g)-approximation algorithm when the input includes and Saberi [11] applies only to23 graphs embedded on orientable surfaces.24 Chekuri and Sidiropoulos [3

  9. DATABASE Open Access RAG: An update to the RNA-As-Graphs resource

    E-Print Network [OSTI]

    Schlick, Tamar

    DATABASE Open Access RAG: An update to the RNA-As-Graphs resource Joseph A Izzo1 , Namhee Kim1 utilize the benefits of relational database, and improvements to several of the utilities such as directed/labeled graphs and a subgraph search program. Conclusions: The RAG updates presented here augment the database

  10. A SURVEY ON HAMILTON CYCLES IN DIRECTED GRAPHS DANIELA KUHN AND DERYK OSTHUS

    E-Print Network [OSTI]

    K√ľhn, Daniela

    A SURVEY ON HAMILTON CYCLES IN DIRECTED GRAPHS DANIELA K¨UHN AND DERYK OSTHUS Abstract. We survey some recent results on long-standing conjectures regard- ing Hamilton cycles in directed graphs towards Kelly's conjecture on Hamilton decompositions of regular tournaments: the edges of every regular

  11. EDGE-DISJOINT HAMILTON CYCLES IN GRAPHS DEMETRES CHRISTOFIDES, DANIELA KUHN AND DERYK OSTHUS

    E-Print Network [OSTI]

    Osthus, Deryk

    EDGE-DISJOINT HAMILTON CYCLES IN GRAPHS DEMETRES CHRISTOFIDES, DANIELA K¨UHN AND DERYK OSTHUS at least n/8 edge-disjoint Hamilton cycles. More generally, we give an asymptotically best possible answer for the number of edge-disjoint Hamilton cycles that a graph G with minimum degree must have. We also prove

  12. Bent Hamilton Cycles in d-Dimensional Grid Graphs Department of Computer Science

    E-Print Network [OSTI]

    Sawada, Joe

    Bent Hamilton Cycles in d-Dimensional Grid Graphs F. Ruskey Department of Computer Science Classifications: 05C45, 05C38 Abstract A bent Hamilton cycle in a grid graph is one in which each edge Hamilton cycle if some dimension is even and d 3, and does not have a bent Hamilton cycle if all

  13. A conjecture of Biggs concerning the resistance of a distance-regular graph

    E-Print Network [OSTI]

    Markowsky, Greg

    2010-01-01T23:59:59.000Z

    Previously, Biggs has conjectured that the resistance between any two points on a distance-regular graph of valency greater than 2 is bounded by twice the resistance between adjacent points. We prove this conjecture, give the sharp constant for the inequality, and display the graphs for which the conjecture most nearly fails. Some necessary background material is included, as well as some consequences.

  14. Dig-ta Video, Learn-ng Styes, and Student Understanding of Kinematics Graphs

    E-Print Network [OSTI]

    Zollman, Dean

    Dig-ta Video, Learn-ng Styes, and Student Understanding of Kinematics Graphs Teresa Larkin Video, Learning Styles, and Student Understanding of Kinematics Graphs Introduction Student learning interactive digital video as well preferences and student understanding and their ability to interpret motion

  15. Graph-based simulated annealing: A hybrid approach to stochastic modeling of complex

    E-Print Network [OSTI]

    Kroese, Dirk P.

    of the system, where the energy is associated with its surface area. The advantage is that for model fittingGraph-based simulated annealing: A hybrid approach to stochastic modeling of complex is based on a hybrid approach, where in a first step a graph model is developed using ideas from stochastic

  16. Compositionality in Synchronous Data Flow: Modular Code Generation from Hierarchical SDF Graphs

    E-Print Network [OSTI]

    Compositionality in Synchronous Data Flow: Modular Code Generation from Hierarchical SDF Graphs in Synchronous Data Flow: Modular Code Generation from Hierarchical SDF Graphs Stavros Tripakis, Dai Bui, Bert of California, Berkeley stavros, daib, eal@eecs.berkeley.edu October 20, 2009 Abstract Hierarchical SDF models

  17. The power graph of a finite group, II Peter J. Cameron

    E-Print Network [OSTI]

    Cameron, Peter

    The power graph of a finite group, II Peter J. Cameron School of Mathematical Sciences Queen Mary, University of London Mile End Road London E1 4NS, U.K. Abstract The directed power graph of a group G is the digraph with vertex set G, having an arc from y to x whenever x is a power of y; the undirected power

  18. Energy Models for Drawing Signed Graphs Anne-Marie Kermarrec and Afshin Moin

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Energy Models for Drawing Signed Graphs Anne-Marie Kermarrec and Afshin Moin INRIA Rennes Bretagne-dimensional space. Energy models are the prevalent approach to graph drawing. In this paper, we propose energy) or as negative (repulsive). The existent energy models do not discriminate against edge sign. Hence, they do

  19. WILD QUOTIENT SURFACE SINGULARITIES WHOSE DUAL GRAPHS ARE NOT STAR-SHAPED

    E-Print Network [OSTI]

    Schröer, Stefan

    WILD QUOTIENT SURFACE SINGULARITIES WHOSE DUAL GRAPHS ARE NOT STAR-SHAPED HIROYUKI ITO AND STEFAN- zini on wild quotient singularities in dimension two. Using Kato's theory of log structures and log of Heisenberg groups lead to examples of wild quotient singularities where the dual graph contains at least two

  20. Graph Mining for Object Tracking in Videos Fabien Diot1,2

    E-Print Network [OSTI]

    Graph Mining for Object Tracking in Videos Fabien Diot1,2 , Elisa Fromont1 , Baptiste Jeudy1 of graph mining for tracking objects in videos with moving cameras and without any contextual information on the objects to track. To make the mining algorithm efficient, we benefit from a video representation based

  1. Solving planning-graph by compiling it into CSP Minh Binh Do & Subbarao Kambhampati

    E-Print Network [OSTI]

    Kambhampati, Subbarao

    Solving planning-graph by compiling it into CSP Minh Binh Do & Subbarao Kambhampati Department to adapt CSP search techniques into the backward search phase of Graphplan. This paper describes GP-CSP, a system that does planning by automati- cally converting Graphplan's planning graph into a CSP encoding

  2. K6 MINORS IN LARGE 6-CONNECTED GRAPHS Ken-ichi Kawarabayashi

    E-Print Network [OSTI]

    Norin, Sergey

    Princeton, NJ 08544, USA Robin Thomas2 School of Mathematics Georgia Institute of Technology Atlanta-20146 Hamburg, Germany ABSTRACT J√łrgensen conjectured that every 6-connected graph G with no K6 minor hand, Conjecture 1.1 provides a nice and clean statement for 6-connected graphs. Unfortunately, it, too

  3. INDDGO: Integrated Network Decomposition & Dynamic programming for Graph Optimization

    SciTech Connect (OSTI)

    Groer, Christopher S [ORNL; Sullivan, Blair D [ORNL; Weerapurage, Dinesh P [ORNL

    2012-10-01T23:59:59.000Z

    It is well-known that dynamic programming algorithms can utilize tree decompositions to provide a way to solve some \\emph{NP}-hard problems on graphs where the complexity is polynomial in the number of nodes and edges in the graph, but exponential in the width of the underlying tree decomposition. However, there has been relatively little computational work done to determine the practical utility of such dynamic programming algorithms. We have developed software to construct tree decompositions using various heuristics and have created a fast, memory-efficient dynamic programming implementation for solving maximum weighted independent set. We describe our software and the algorithms we have implemented, focusing on memory saving techniques for the dynamic programming. We compare the running time and memory usage of our implementation with other techniques for solving maximum weighted independent set, including a commercial integer programming solver and a semi-definite programming solver. Our results indicate that it is possible to solve some instances where the underlying decomposition has width much larger than suggested by the literature. For certain types of problems, our dynamic programming code runs several times faster than these other methods.

  4. Bond Graph Modeling of Current Diffusion in Magnetic Cores Herv Morel, Bruno Allard, Sabrine M'Rad, Cyril Buttay

    E-Print Network [OSTI]

    Paris-Sud XI, Universitť de

    Bond Graph Modeling of Current Diffusion in Magnetic Cores Hervť Morel, Bruno Allard, Sabrine M, F-69621 Villeurbanne Cedex, France KEYBOARD: Bond Graphs, Variational approximation, Diffusive with the diffusion representation. Both approaches yield a same bond graph representation. 2. MODELING CURRENT

  5. Vertex-Colored Graphs, Bicycle Spaces and Mahler Measure Kalyn R. Lamey Daniel S. Silver Susan G. Williams

    E-Print Network [OSTI]

    Williams, Susan

    Vertex-Colored Graphs, Bicycle Spaces and Mahler Measure Kalyn R. Lamey Daniel S. Silver Susan G to the bicycle space of the graph. For graphs G with a free Zd -action by automorphisms, C is a finitely identify the subspace C0 of based conservative vertex colorings with the bicycle space B of G. In section 3

  6. A note on QUBO instances defined on Chimera graphs

    E-Print Network [OSTI]

    Sanjeeb Dash

    2013-07-01T23:59:59.000Z

    McGeoch and Wang (2013) recently obtained optimal or near-optimal solutions to some quadratic unconstrained boolean optimization (QUBO) problem instances using a 439 qubit D-Wave Two quantum computing system in much less time than with the IBM ILOG CPLEX mixed-integer quadratic programming (MIQP) solver. The problems studied by McGeoch and Wang are defined on subgraphs -- with up to 439 nodes -- of Chimera graphs. We observe that after a standard reformulation of the QUBO problem as a mixed-integer linear program (MILP), the specific instances used by McGeoch and Wang can be solved to optimality with the CPLEX MILP solver in much less time than the time reported in McGeoch and Wang for the CPLEX MIQP solver. However, the solution time is still more than the time taken by the D-Wave computer in the McGeoch-Wang tests.

  7. Linking SARAH and MadGraph using the UFO format

    E-Print Network [OSTI]

    Staub, Florian

    2012-01-01T23:59:59.000Z

    SARAH is a Mathematica package optimized for the fast, efficient and precise study of supersymmetric models beyond the MSSM: a new model can be defined in a short form and all vertices are derived. This allows SARAH to create model files for FeynArts/FormCalc, CalcHep/CompHep and WHIZARD/OMEGA. The newest version of SARAH now provides the possibility to create model files in the UFO format which is supported by MadGraph 5, MadAnalysis 5, GoSam, and soon by Herwig++. Furthermore, SARAH also calculates the mass matrices, RGEs and 1-loop corrections to the mass spectrum. This information is used to write source code for SPheno in order to create a precision spectrum generator for the given model. This spectrum-generator-generator functionality as well as the output of WHIZARD and CalcHep model files have seen further improvement in this version.

  8. A framework for graph-based synthesis, analysis, and visualization of HPC cluster job data.

    SciTech Connect (OSTI)

    Mayo, Jackson R.; Kegelmeyer, W. Philip, Jr.; Wong, Matthew H.; Pebay, Philippe Pierre; Gentile, Ann C.; Thompson, David C.; Roe, Diana C.; De Sapio, Vincent; Brandt, James M.

    2010-08-01T23:59:59.000Z

    The monitoring and system analysis of high performance computing (HPC) clusters is of increasing importance to the HPC community. Analysis of HPC job data can be used to characterize system usage and diagnose and examine failure modes and their effects. This analysis is not straightforward, however, due to the complex relationships that exist between jobs. These relationships are based on a number of factors, including shared compute nodes between jobs, proximity of jobs in time, etc. Graph-based techniques represent an approach that is particularly well suited to this problem, and provide an effective technique for discovering important relationships in job queuing and execution data. The efficacy of these techniques is rooted in the use of a semantic graph as a knowledge representation tool. In a semantic graph job data, represented in a combination of numerical and textual forms, can be flexibly processed into edges, with corresponding weights, expressing relationships between jobs, nodes, users, and other relevant entities. This graph-based representation permits formal manipulation by a number of analysis algorithms. This report presents a methodology and software implementation that leverages semantic graph-based techniques for the system-level monitoring and analysis of HPC clusters based on job queuing and execution data. Ontology development and graph synthesis is discussed with respect to the domain of HPC job data. The framework developed automates the synthesis of graphs from a database of job information. It also provides a front end, enabling visualization of the synthesized graphs. Additionally, an analysis engine is incorporated that provides performance analysis, graph-based clustering, and failure prediction capabilities for HPC systems.

  9. A PTAS for the Classical Ising Spin Glass Problem on the Chimera Graph Structure

    E-Print Network [OSTI]

    Rishi Saket

    2013-07-01T23:59:59.000Z

    We present a polynomial time approximation scheme (PTAS) for the minimum value of the classical Ising Hamiltonian with linear terms on the Chimera graph structure as defined in the recent work of McGeoch and Wang. The result follows from a direct application of the techniques used by Bansal, Bravyi and Terhal who gave a PTAS for the same problem on planar and, in particular, grid graphs. We also show that on Chimera graphs, the trivial lower bound is within a constant factor of the optimum.

  10. Homogeneous Factorisations of Graphs and Michael Giudici a, Cai Heng Li a

    E-Print Network [OSTI]

    Giudici, Michael

    Homogeneous Factorisations of Graphs and Digraphs Michael Giudici a, Cai Heng Li a Primoz Potocnik@maths.uwa.edu.au (Michael Giudici), li@maths.uwa.edu.au (Cai Heng Li), primoz.potocnik@fmf.uni-lj.si (Primoz Preprint

  11. Maximal Independent Sets In Graphs With At Most r Goh Chee Ying

    E-Print Network [OSTI]

    Sagan, Bruce

    Maximal Independent Sets In Graphs With At Most r Cycles Goh Chee Ying Department of Mathematics National University of Singapore Singapore goh chee ying@moe.edu.sg Koh Khee Meng Department of Mathematics

  12. Omega: an Overlap-graph de novo Assembler for Meta-genomics

    SciTech Connect (OSTI)

    Haider, Bahlul [ORNL; Ahn, Tae-Hyuk [ORNL; Bushnell, Brian [U.S. Department of Energy, Joint Genome Institute; Chai, JJ [ORNL; Copeland, Alex [U.S. Department of Energy, Joint Genome Institute; Pan, Chongle [ORNL

    2014-01-01T23:59:59.000Z

    Motivation: Metagenomic sequencing allows reconstruction of mi-crobial genomes directly from environmental samples. Omega (overlap-graph metagenome assembler) was developed here for assembling and scaffolding Illumina sequencing data of microbial communities. Results: Omega found overlaps between reads using a prefix/suffix hash table. The overlap graph of reads was simplified by removing transitive edges and trimming small branches. Unitigs were generat-ed based on minimum cost flow analysis of the overlap graph. Obtained unitigs were merged to contigs and scaffolds using mate-pair information. Omega was compared with two de Bruijn graph assemblers, SOAPdenovo and IDBA-UD, using a publically-available Illumina sequencing dataset of a 64-genome mock com-munity. The assembly results were verified by their alignment with reference genomes. The overall performances of the three assem-blers were comparable and each assembler provided best results for a subset of genomes.

  13. The Minimum Rank, Inverse Inertia, and Inverse Eigenvalue Problems for Graphs.

    E-Print Network [OSTI]

    Kempton, Mark Condie

    2010-01-01T23:59:59.000Z

    ??For a graph G we define S(G) to be the set of all real symmetric n by n matrices whose off-diagonal zero/nonzero pattern is describedÖ (more)

  14. Forced Orientation of Graphs B. FARZAD , M. MAHDIAN y , E.S. MAHMOODIAN z ,

    E-Print Network [OSTI]

    Saberi, Amin

    Forced Orientation of Graphs B. FARZAD #3; , M. MAHDIAN y , E.S. MAHMOODIAN z , A. SABERI x , AND B, Georgia Institute of Technology, Atlanta, USA. (saberi@cc.gatech.edu) { Department of Computer Science

  15. A New Approach to Argument by Analogy: Extrapolation and Chain Graphs Daniel Steel

    E-Print Network [OSTI]

    Steel, Daniel

    A New Approach to Argument by Analogy: Extrapolation and Chain Graphs Daniel Steel Department of Philosophy 503 S Kedzie Hall East Lansing, MI 48824-1032 steel@msu.edu #12;1. Introduction. In order to make

  16. THE SPECTRAL RADIUS OF INFINITE GRAPHS N. L. BIGGS, BOJAN MOHAR AND JOHN SHAWE-TAYLOR

    E-Print Network [OSTI]

    Mohar, Bojan

    THE SPECTRAL RADIUS OF INFINITE GRAPHS N. L. BIGGS, BOJAN MOHAR AND JOHN SHAWE-TAYLOR 1 follows from Theorem 2.2. #12;118 N. L. BIGGS, B. MOHAR AND J. SHAWE-TAYLOR 3. The expanding case

  17. Feedback vertex sets and disjoint cycles in planar (di)graphs

    E-Print Network [OSTI]

    graph has a feedback vertex set of cardinality at most k then its treewidth. is bounded ... in linear time, and this is used to nd an algorithm computing a feedback.

  18. The usefulness of the generalised computational model of Term Graph Rewriting Systems (TGRS) for designing and

    E-Print Network [OSTI]

    Banach, Richard

    of programs written in UFO ([8,9]), a state-of-the-art object- oriented functional language, onto equivalent as follows: the next two sections introduce MONSTR and UFO and provide Term Graph Rewriting

  19. Storage device sizing for a hybrid railway traction system by means of bicausal bond graphs

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    (a supercapacitor) included in this system is then discussed. Keywords: bond graph, bicausality In the paper, the example of a supercapacitor process consists of choosing the system structure dimensioning

  20. Design techniques for graph-based error-correcting codes and their applications

    E-Print Network [OSTI]

    Lan, Ching Fu

    2006-04-12T23:59:59.000Z

    by channels afterward. The discovery of turbo codes and rediscovery of Low Density Parity Check codes (LDPC) have revived the research in channel coding with novel ideas and techniques on code concatenation, iterative decoding, graph-based construction...

  1. Coloring Kk-free intersection graphs of geometric objects in the plane

    E-Print Network [OSTI]

    Fox, Jacob

    Coloring Kk-free intersection graphs of geometric objects in the plane Jacob Fox Department that copies are not made or distributed for profit or commercial advantage and that copies bear this notice

  2. Mathematical misconceptions in graphing and central tendency among sixth grade and undergraduate students

    E-Print Network [OSTI]

    Hammer, Mary Elizabeth

    2002-01-01T23:59:59.000Z

    of the requirements for the degree of MASTER OF SCIENCE August 2002 Major Subject: Curriculum and Instruction MATHEMATICAL MISCONCEPTIONS IN GRAPHING AND CENTRAL TENDENCY AMONG SIXTH GRADE AND UNDERGRADUATE STUDENTS A Thesis by MARY ELIZABETH HAMMER... lfeldt / Head of De artment) August 2002 Major Subject: Curriculum and Instruction 111 ABSTRACT Mathematical Misconceptions in Graphing and Central Tendency Among Sixth Grade and Undergraduate Students. (August 2002) Mary Elizabeth Hammer, B. A...

  3. Exact sampling of graphs with prescribed degree correlations

    E-Print Network [OSTI]

    Bassler, Kevin E; Erd?s, Pťter L; Miklůs, IstvŠn; Toroczkai, ZoltŠn

    2015-01-01T23:59:59.000Z

    Many real-world networks exhibit correlations between the node degrees. For instance, in social networks nodes tend to connect to nodes of similar degree. Conversely, in biological and technological networks, high-degree nodes tend to be linked with low-degree nodes. Degree correlations also affect the dynamics of processes supported by a network structure, such as the spread of opinions or epidemics. The proper modelling of these systems, i.e., without uncontrolled biases, requires the sampling of networks with a specified set of constraints. We present a solution to the sampling problem when the constraints imposed are the degree correlations. In particular, we develop an efficient and exact method to construct and sample graphs with a specified joint-degree matrix, which is a matrix providing the number of edges between all the sets of nodes of a given degree, for all degrees, thus completely specifying all pairwise degree correlations, and additionally, the degree sequence itself. Our algorithm always pro...

  4. Hierarchical graphs for better annotations of rule-based models of biochemical systems

    SciTech Connect (OSTI)

    Hu, Bin [Los Alamos National Laboratory; Hlavacek, William [Los Alamos National Laboratory

    2009-01-01T23:59:59.000Z

    In the graph-based formalism of the BioNetGen language (BNGL), graphs are used to represent molecules, with a colored vertex representing a component of a molecule, a vertex label representing the internal state of a component, and an edge representing a bond between components. Components of a molecule share the same color. Furthermore, graph-rewriting rules are used to represent molecular interactions, with a rule that specifies addition (removal) of an edge representing a class of association (dissociation) reactions and with a rule that specifies a change of vertex label representing a class of reactions that affect the internal state of a molecular component. A set of rules comprises a mathematical/computational model that can be used to determine, through various means, the system-level dynamics of molecular interactions in a biochemical system. Here, for purposes of model annotation, we propose an extension of BNGL that involves the use of hierarchical graphs to represent (1) relationships among components and subcomponents of molecules and (2) relationships among classes of reactions defined by rules. We illustrate how hierarchical graphs can be used to naturally document the structural organization of the functional components and subcomponents of two proteins: the protein tyrosine kinase Lck and the T cell receptor (TCR)/CD3 complex. Likewise, we illustrate how hierarchical graphs can be used to document the similarity of two related rules for kinase-catalyzed phosphorylation of a protein substrate. We also demonstrate how a hierarchical graph representing a protein can be encoded in an XML-based format.

  5. How the permutation of edges of a metric graph affects the number of points moving along the edges

    E-Print Network [OSTI]

    V. L. Chernyshev; A. A. Tolchennikov

    2014-10-18T23:59:59.000Z

    We consider a dynamical system on a metric graph, that corresponds to a semiclassical solution of a time-dependent Schr\\"odinger equation. We omit all details concerning mathematical physics and work with a purely discrete problem. We find a weak inequality representation for the number of points coming out of the vertex of an arbitrary tree graph. We apply this construction to an "H-junction" graph. We calculate the difference between numbers of moving points corresponding to the permutation of edges. Then we find a symmetrical difference of the number of points moving along the edges of a metric graph.

  6. Decay of Correlations for the Hardcore Model on the $d$-regular Random Graph

    E-Print Network [OSTI]

    Nayantara Bhatnagar; Allan Sly; Prasad Tetali

    2014-05-23T23:59:59.000Z

    A key insight from statistical physics about spin systems on random graphs is the central role played by Gibbs measures on trees. We determine the local weak limit of the hardcore model on random regular graphs asymptotically until just below its condensation threshold, showing that it converges in probability locally in a strong sense to the free boundary condition Gibbs measure on the tree. As a consequence we show that the reconstruction threshold on the random graph, indicative of the onset of point to set spatial correlations, is equal to the reconstruction threshold on the $d$-regular tree for which we determine precise asymptotics. We expect that our methods will generalize to a wide range of spin systems for which the second moment method holds.

  7. 17Solar Storm Energy and Pie Graphs The pie charts below show approximately how various forms of energy

    E-Print Network [OSTI]

    17Solar Storm Energy and Pie Graphs The pie charts below show approximately how various forms of energy are involved in a solar flare. Flares occur when stored magnetic energy is suddenly released magnetic energy Graph of solar flare energy forms Problem 1 - About what percentages of each of the four

  8. GeoTriples: a Tool for Publishing Geospatial Data as RDF Graphs Using R2RML Mappings

    E-Print Network [OSTI]

    Koubarakis, Manolis

    GeoTriples: a Tool for Publishing Geospatial Data as RDF Graphs Using R2RML Mappings Kostis the linked data paradigm. Therefore, Earth Ob- servation data and other kinds of geospatial data and geospatial data into RDF graphs. GeoTriples goes beyond the state of the art by extending the R2RML mapping

  9. Graph Data Format Workshop Report Ulrik Brandes 1 , M. Scott Marshall 2 , and Stephen C. North 3

    E-Print Network [OSTI]

    Brandes, Ulrik

    Graph Data Format Workshop Report Ulrik Brandes 1 , M. Scott Marshall 2 , and Stephen C. North 3 1, The Netherlands. scott@cwi.nl 3 AT&T Research, 180 Park Ave., Bldg. 103, Florham Park, NJ 07932-0971, U.S.A. north workshop was held in conjunction with Graph Drawing 2000. The participants identi#12;ed requirements

  10. The Elusive Hamilton Problem for Cayley Graphs--an 28th Clemson Mini-Conference on Discrete Mathematics and Algorithms

    E-Print Network [OSTI]

    Goddard, Wayne

    The Elusive Hamilton Problem for Cayley Graphs--an Overview 28th Clemson Mini State University October 3, 2013 Erik Westlund (KSU) Elusive Hamilton Problem for Cayley Graphs October} Cay(Z12; {2, 3, 4} ) Cay(D4; {a, b} ) Cay(Z4 2; S ) Erik Westlund (KSU) Elusive Hamilton Problem

  11. Analyzing the Facebook friendship graph S. Catanese1, P. De Meo2, E. Ferrara3, G. Fiumara1

    E-Print Network [OSTI]

    Ferrara, Emilio

    Analyzing the Facebook friendship graph S. Catanese1, P. De Meo2, E. Ferrara3, G. Fiumara1 1Dept Internet 20 September 2010, Berlin Catanese, De Meo, Ferrara, Fiumara () Analyzing the Facebook friendship Issues Catanese, De Meo, Ferrara, Fiumara () Analyzing the Facebook friendship graph MIFI 2010, 20

  12. In "Handbook of Mathematical Models in Computer Vision", Springer, 2006 p.1 Graph Cuts in Vision and Graphics

    E-Print Network [OSTI]

    Boykov, Yuri

    and Graphics: Theories and Applications Yuri Boykov and Olga Veksler Computer Science, The University the corresponding graph. Thus, many applications in vision and graphics use min-cut algorithms as a tool for computing optimal hypersurfaces. Secondly, graph-cuts also work as a powerful energy minimization tool

  13. Improved vertex cover algorithms for fixed genus graphs through genus reduction and planar separation

    E-Print Network [OSTI]

    Gupton, Kevin Thomas

    2003-01-01T23:59:59.000Z

    , problems are restricted to decision problems? problems with yes/no answers. The VERTEX CovER problem formulated as a decision problem is "Given a graph G = (V, E) and positive cover k, does there exist a vertex cover of G whose size is at most k...: "Given a graph G = (V, E) and parameter k, does there exist a vertex cover C c: V for G such that C~ & k?" As a decision problem, Karp first demonstrated quantitatively how "hard" VERTEx CovER is to solve by showing that vERTEx covER is NP-complete [16...

  14. Automation of the Dipole Subtraction Method in MadGraph/MadEvent

    E-Print Network [OSTI]

    Rikkert Frederix; Thomas Gehrmann; Nicolas Greiner

    2008-08-15T23:59:59.000Z

    We present the implementation of the dipole subtraction formalism for the real radiation contributions to any next-to-leading order QCD process in the MadGraph/MadEvent framework. Both massless and massive dipoles are considered. Starting from a specific (n+1)-particle process the package provides a Fortran code for all possible dipoles to all Born processes that constitute the subtraction term to the (n+1)-particle process. The output files are given in the usual "MadGraph StandAlone" style using helicity amplitudes.

  15. Multiclass Diffuse Interface Models for Semi-Supervised Learning on Graphs

    E-Print Network [OSTI]

    Garcia-Cardona, Cristina; Percus, Allon G

    2012-01-01T23:59:59.000Z

    We present a graph-based variational algorithm for multiclass classification of high-dimensional data, motivated by total variation techniques. The energy functional is based on a diffuse interface model with a periodic potential. We augment the model by introducing an alternative measure of smoothness that preserves symmetry among the class labels. Through this modification of the standard Laplacian, we construct an efficient multiclass method that allows for sharp transitions between classes. The experimental results demonstrate that our approach is competitive with the state of the art among other graph-based algorithms.

  16. View

    E-Print Network [OSTI]

    2010-03-14T23:59:59.000Z

    Aug 19, 2009 ... linear-algebraic and graph theoretic properties of this matrix class. The con- ..... The MatLab solvers linprog and quadprog were used.

  17. Exploring Aggregate Effect with Weighted Transcoding Graphs for Efficient Cache Replacement in Transcoding Proxies

    E-Print Network [OSTI]

    Chen, Ming-Syan

    Exploring Aggregate Effect with Weighted Transcoding Graphs for Efficient Cache Replacement University Taipei, Taiwan, ROC E-mail: {cychang@arbor.ee.ntu.edu.tw; mschen@cc.ee.ntu.edu.tw} Abstract This paper explores the aggregate effect when caching multiple versions of the same Web object

  18. Optimizing Graph Algorithms for Improved Cache Performance*+ Joon-Sang Park

    E-Print Network [OSTI]

    Prasanna, Viktor K.

    . For these algorithms, we demonstrate up to 2√? improvement in real execution time by using a simple cache- friendly graphs. We show performance improvements of 2√? - 3√? in real execution time by using the technique N and C are the problem size and cache size respectively. Experimental results show that this cache

  19. A Genetic Algorithm based Approach for Multi-Objective Data-Flow Graph Optimization

    E-Print Network [OSTI]

    Coello, Carlos A. Coello

    that the correct- ness of algebraic transformations realized by the underlying genetic operators selection shown for power optimization. In order to avoid inferior results caused by the counteracting demandsA Genetic Algorithm based Approach for Multi-Objective Data-Flow Graph Optimization Birger Landwehr

  20. On the Number of Cycles in Planar Graphs Kevin Buchin1

    E-Print Network [OSTI]

    Fuchs, Gunter

    technique. Combining both, we show that there is no planar graph with more than 2.8927n simple cycles cycles can be obtained by combining an upper bound on the number of triangulations with an upper bound spanning cycles on n points with an alternative approach. This bound is better than the combined bound

  1. Development of the TIGRE This describes the TIGRE method for combinator graph reduction.

    E-Print Network [OSTI]

    Koopman, Philip

    been previously implemented for the G-Ma- chine graph reduction implementation on a VAX (Peyton Jones 1987). In VAX assembly language, unwinding a node while traversing the stack requires four instructions, on average, processing nodes for stack unwinding costs: (4 * 1.38) + 7 = 12.52 VAX instructions per

  2. Planar Hop Spanners for Unit Disk Graphs Nicolas Catusse, Victor Chepoi, and Yann Vax`es

    E-Print Network [OSTI]

    Chepoi, Victor

    Planar Hop Spanners for Unit Disk Graphs Nicolas Catusse, Victor Chepoi, and Yann Vax`es Marseille Cedex 9, France {nicolas.catusse,victor.chepoi,yann.vaxes}@lif.univ-mrs.fr Abstract. The simplest;2 Nicolas Catusse, Victor Chepoi, and Yann Vax`es factors (see [9], for instance), the problem

  3. Muller's ratchet in random graphs and scale-free networks Paulo R. A. Campos,1,

    E-Print Network [OSTI]

    Dionisio, Francisco

    Muller's ratchet in random graphs and scale-free networks Paulo R. A. Campos,1, * Jaime Combad√£o,2 manuscript received 1 September 2006; published 4 October 2006 Muller's ratchet is an evolutionary process study the speed of Muller's ratchet in a population subdivided into many small subpopulations connected

  4. Absolutely continuous spectrum implies ballistic transport for quantum particles in a random potential on tree graphs

    SciTech Connect (OSTI)

    Aizenman, Michael [Departments of Physics and Mathematics, Princeton University, Princeton, New Jersey 08544 (United States); Warzel, Simone [Zentrum Mathematik, TU Munich, Boltzmannstr. 3, 85747 Garching (Germany)

    2012-09-15T23:59:59.000Z

    We discuss the dynamical implications of the recent proof that for a quantum particle in a random potential on a regular tree graph absolutely continuous (ac) spectrum occurs non-perturbatively through rare fluctuation-enabled resonances. The main result is spelled in the title.

  5. Fully Distributed Trust Model based on Trust Graph for Mobile Ad hoc Networks

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Fully Distributed Trust Model based on Trust Graph for Mobile Ad hoc Networks Mawloud Omar, Yacine University of Technology, France. bouabdal@hds.utc.fr Abstract A mobile ad hoc network (MANET) is a wireless that defines who trusts who and how. Our work aims to provide a fully distributed trust model for mobile ad hoc

  6. A Methodology for Empirical Analysis of Brain Connectivity through Graph Mining

    E-Print Network [OSTI]

    Xie, Mengjun

    A Methodology for Empirical Analysis of Brain Connectivity through Graph Mining Jiang Bian, Josh M Informatics Brain Imaging Research Center, Psychiatric Research Institute University of Arkansas for Medical and functional brain connectivity networks and has helped researchers conceive the effects of neurological

  7. Intro. to Linear Algebra 250C Extra Credit Project 2 ---Graphs and Markov Processes

    E-Print Network [OSTI]

    Woodward, Christopher

    of the week? How do you write this in matrix form? Use MATLAB to do the calculations. We are now interested A is called the transition matrix for the process. 9. Using MATLAB, find A k for k = 1, 2, 3, 5, 10, 20, 50Intro. to Linear Algebra 250­C Extra Credit Project 2 --- Graphs and Markov Processes Introduction

  8. Intro. to Linear Algebra 250-C Extra Credit Project 2 --Graphs and Markov Processes

    E-Print Network [OSTI]

    Woodward, Christopher

    that each column of A should sum up to 1 (why?). Use MATLAB to create the vectors x, y and the matrix A. 3 of the week? How do you write this in matrix form? Use MATLAB to do the calculations. We are now interestedIntro. to Linear Algebra 250-C Extra Credit Project 2 -- Graphs and Markov Processes Introduction

  9. Novel approaches for solving large-scale optimization problems on graphs

    E-Print Network [OSTI]

    Trukhanov, Svyatoslav

    2009-05-15T23:59:59.000Z

    . . . . . . . . . . . . . . . . . . . . . . . 97 8 Parameters of calculated weighted diversified portfolios correspon- ding to 500-day trading periods . . . . . . . . . . . . . . . . . . . . . 110 9 Graph parameters for small test-bed . . . . . . . . . . . . . . . . . . 126 10 Number of k... . . . . . . . . . . . . . . . . . . 29 5 Crown structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 6 t-hat structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 7 2-club and 2-clique example . . . . . . . . . . . . . . . . . . . . . . . 54 8...

  10. Time-varying Reeb Graphs for Continuous Space-Time Data Herbert Edelsbrunner

    E-Print Network [OSTI]

    Pascucci, Valerio

    and/or a fee. SOCG '04 New York City, New York USA Copyright 2004 ACM ?? . . . $4.99. of dataTime-varying Reeb Graphs for Continuous Space-Time Data Herbert Edelsbrunner , John Harer , Ajith the evolving sequence into a single, partially persistent data structure. We envision this data structure

  11. 1 Introduction 1 1.1 Graphs, digraphs, and homomorphisms 1

    E-Print Network [OSTI]

    Hell, Pavol

    CONTENTS 1 Introduction 1 1.1 Graphs, digraphs, and homomorphisms 1 1.2 Homomorphisms preserve adjacency 3 1.3 Homomorphisms generalize colourings 6 1.4 The existence of homomorphisms 10 1.5 Homomorphisms generalize isomorphisms 16 1.6 Homomorphic equivalence 18 1.7 The composition of homomorphisms 20

  12. Graphs of models for exploring design spaces in the engineering of Human Computer Interaction

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Graphs of models for exploring design spaces in the engineering of Human Computer Interaction +33 (0)4 76 51 48 54 gaelle.calvary@imag.fr ABSTRACT Model Driven Engineering (MDE) has focused creativity in the early phases. Our research aims at stretching MDE all over the design process including

  13. Kronk, Hudson V., Associate Professor, PhD, 1964, Michigan State University: Graph theory.

    E-Print Network [OSTI]

    Suzuki, Masatsugu

    227 Kronk, Hudson V., Associate Professor, PhD, 1964, Michigan State University: Graph theory) Schick, Anton, Associate Professor, PhD, 1983, Michigan State University: Statistics, probability. (1984, conformal field theory. (1979) Ferry, Steven, Distinguished Professor, PhD, 1973, University of Michigan

  14. Hamilton Cycles which Extend Transposition Matchings in Cayley Graphs of S n

    E-Print Network [OSTI]

    Savage, Carla D.

    Hamilton Cycles which Extend Transposition Matchings in Cayley Graphs of S n Frank Ruskey \\Lambda matching M b in Cay(B : S n ). We show here when n ? 4 that for any b 2 B, there is a Hamilton cycle in Cay only a Hamilton path, the question is still open and is, in fact, a special case of the more general

  15. Hamilton Cycles Containing Randomly Selected Edges in Random Regular Graphs \\Lambda

    E-Print Network [OSTI]

    Robinson, Robert W.

    Hamilton Cycles Containing Randomly Selected Edges in Random Regular Graphs \\Lambda R. W. Robinson oriented root edges have been randomly specified for the cycle to contain. The Hamilton cycle must be orientable to agree with all of the orientations on the j root edges. It is shown that the requisite Hamilton

  16. EDGE-DISJOINT HAMILTON CYCLES IN RANDOM GRAPHS FIACHRA KNOX, DANIELA KUHN AND DERYK OSTHUS

    E-Print Network [OSTI]

    K√ľhn, Daniela

    EDGE-DISJOINT HAMILTON CYCLES IN RANDOM GRAPHS FIACHRA KNOX, DANIELA K¨UHN AND DERYK OSTHUS a collection of (G)/2 edge-disjoint Hamilton cycles in G Gn,p, plus an additional edge-disjoint matching of Frieze and Krivelevich. 1. Introduction The question of how many edge-disjoint Hamilton cycles one can

  17. The critical group of a graph Texas State U., San Marcos, March 21th, 2014.

    E-Print Network [OSTI]

    Sin, Peter

    -firing game (Björner-Lovasz-Shor, Gabrielov, Biggs); #12;This talk is about the critical group, a finite-Tang-Wiesenfeld, Dhar); its combinatorial variant: the Chip-firing game (Björner-Lovasz-Shor, Gabrielov, Biggs-Lovasz-Shor, Gabrielov, Biggs); in arithmetic geometry: Picard group, graph Jacobian (Lorenzini). We'll consider

  18. The critical group of a graph Millican Colloquium, UNT, March 24th, 2014.

    E-Print Network [OSTI]

    Sin, Peter

    -firing game (Björner-Lovasz-Shor, Gabrielov, Biggs); #12;This talk is about the critical group, a finite-Tang-Wiesenfeld, Dhar); its combinatorial variant: the Chip-firing game (Björner-Lovasz-Shor, Gabrielov, Biggs-Lovasz-Shor, Gabrielov, Biggs); in arithmetic geometry: Picard group, graph Jacobian (Lorenzini). We'll consider

  19. A functional central limit theorem for interacting particle systems on transitive graphs

    E-Print Network [OSTI]

    Paul Doukhan; Gabriel Lang; Sana Louhichi; Bernard Ycart

    2007-04-12T23:59:59.000Z

    A finite range interacting particle system on a transitive graph is considered. Assuming that the dynamics and the initial measure are invariant, the normalized empirical distribution process converges in distribution to a centered diffusion process. As an application, a central limit theorem for certain hitting times, interpreted as failure times of a coherent system in reliability, is derived.

  20. NLS ground states on graphs Riccardo Adami # , Enrico Serra + , Paolo Tilli

    E-Print Network [OSTI]

    Abstract We investigate the existence of ground states for the subcritical NLS energy on metric graphs. In particular, we find out a topologi­ cal assumption that guarantees the nonexistence of ground states, and give an example in which the assumption is not fulfilled and ground states actually exist. In order

  1. The Effect of Neighbor Graph Connectivity on Coverage Redundancy in Wireless Sensor Networks

    E-Print Network [OSTI]

    Varela, Carlos

    that the network field is covered by these nodes at the desired ratio while the usage of the energy by the sensorThe Effect of Neighbor Graph Connectivity on Coverage Redundancy in Wireless Sensor Networks problems in wireless sensor networks. To reduce the energy consumption that arises when the high number

  2. A Discriminative Model-Constrained Graph Cuts Approach to Fully Automated Pediatric

    E-Print Network [OSTI]

    Carneiro, Gustavo

    A Discriminative Model-Constrained Graph Cuts Approach to Fully Automated Pediatric Brain Tumor of Radiology, University Medical Center, Erlangen, Germany 4 Siemens, CT SE SCR 2, Erlangen, Germany Abstract. In this paper we present a fully automated approach to the segmentation of pediatric brain tumors in multi

  3. LOOP TRANSFORMATIONS FOR INTERFACE-BASED HIERARCHIES IN SDF GRAPHS Jonathan Piat1

    E-Print Network [OSTI]

    Bhattacharyya, Shuvra S.

    LOOP TRANSFORMATIONS FOR INTERFACE-BASED HIERARCHIES IN SDF GRAPHS Jonathan Piat1 , Shuvra S processing (DSP) applica- tions. A restricted version of data-flow, termed synchronous data-flow (SDF of hierarchy (Interface-based SDF) has been proposed allowing more expressivity while maintaining its

  4. Back to Basics: Homogeneous Representations of Multi-Rate Synchronous Dataflow Graphs

    E-Print Network [OSTI]

    Al Hanbali, Ahmad

    Synchronous dataflow (SDF) [1] is a popular class of models of computation and is used to model the temporal are particularly useful in the design of systems where worst-case guarantees on performance must be given. An SDF and processing elements. The class of SDF graphs that we focus on in this paper are called multi-rate SDF (MRSDF

  5. Factor Graphs for Universal Portfolios Andrew J. Bean and Andrew C. Singer

    E-Print Network [OSTI]

    Singer, Andrew C

    transaction costs while taking advantage of side information. We introduce factor graphs as a computational of sequentially investing in a stock market where we have access to a side information sequence and we also must the ratio of the opening price of the jth stock on the (t + 1)th trading period to the opening price

  6. Semantics Guided Filtering of Combinatorial Graph Transformations in Declarative Equation-Based Languages.

    E-Print Network [OSTI]

    Burns, Peter

    required to get the simulation working. The paper is organized as follows: Section 2 introduces Modelica, a new equation-based declarative language. Some specific Modelica language constructs necessary using Modelica. Section 5 gives some preliminary definitions related to the concept of bipartite graphs

  7. Roots xk(y) of a formal power series with applications to graph enumeration

    E-Print Network [OSTI]

    Banaji,. Murad

    the n(y) are formal power series with invertible constant term (coefficients lying in a commutative ringRoots xk(y) of a formal power series f(x, y) = n=0 an(y) xn with applications to graph enumeration and q-series Alan Sokal New York University / University College London Lectures at Queen Mary -- 11, 18

  8. Affine Nested Loop Programs and their Binary Parameterized Dataflow Graph Counterparts

    E-Print Network [OSTI]

    Bhattacharyya, Shuvra S.

    Affine Nested Loop Programs and their Binary Parameterized Dataflow Graph Counterparts Ed F Parameterized static affine nested loop programs can be automatically converted to input-output equivalent Kahn affine nested loop programs which are nested loop programs in which the loop boundaries, the conditions

  9. VIDEO SUMMARIZATION BY SPATIAL-TEMPORAL GRAPH OPTIMIZATION Shi Lu, Michael R. Lyu, Irwin King

    E-Print Network [OSTI]

    King, Kuo Chin Irwin

    VIDEO SUMMARIZATION BY SPATIAL-TEMPORAL GRAPH OPTIMIZATION Shi Lu, Michael R. Lyu, Irwin King SAR {slu, lyu, king}@cse.cuhk.edu.hk ABSTRACT In this paper we present a novel approach for video sum-temporal content cov- erage and visual coherence of the video summary. The ap- proach has three stages. First

  10. Introduction to Physical Systems Modelling with Bond Graphs Jan F. Broenink

    E-Print Network [OSTI]

    Batlle, Carles

    on energy and energy exchange. Analogies between domains are more than just equations being analogous and directed graphs, in which the vertices represent submodels and the edges represent an ideal energy connection between power ports. The vertices are idealised descriptions of physical phenomena

  11. Finite propagation speed for solutions of the wave equation on metric graphs

    E-Print Network [OSTI]

    Vadim Kostrykin; JŁrgen Potthoff; Robert Schrader

    2011-06-04T23:59:59.000Z

    We provide a class of self-adjoint Laplace operators on metric graphs with the property that the solutions of the associated wave equation satisfy the finite propagation speed property. The proof uses energy methods, which are adaptions of corresponding methods for smooth manifolds.

  12. Linear Prediction Models with Graph Regularization for Web-page Categorization

    E-Print Network [OSTI]

    Zhang, Tong

    ! Inc. New York City, NY, USA tzhang@yahoo-inc.com Alexandrin Popescul Yahoo! Inc. Santa Clara, CA, USA popescul@yahoo- inc.com Byron Dom Yahoo! Inc. Santa Clara, CA, USA bdom@yahoo-inc.com ABSTRACT We present that classes of graph neighbors seeded with a text only classifier and further re- fined with an EM

  13. Graph-based Criteria for Spectrum-Aware Clustering in Cognitive Radio Milan Bradonjica, Loukas Lazosb,

    E-Print Network [OSTI]

    Lazos, Loukas

    Graph-based Criteria for Spectrum-Aware Clustering in Cognitive Radio Networks Milan Bradonji, Arizona Email: llazos@ece.arizona.edu Abstract Cognitive radios (CRs) can exploit vacancies in licensed. 1. Introduction Under a fixed spectrum allocation paradigm, frequency bands are licensed

  14. The stackelberg minimum spanning tree game on planar and bounded-treewidth graphs

    E-Print Network [OSTI]

    Cardinal, Jean

    The Stackelberg Minimum Spanning Tree Game is a two-level combinatorial pricing problem introduced at WADSí07. The game is played on a graph, whose edges are colored either red or blue, and where the red edges have a given ...

  15. A Distributed Polylogarithmic Time Algorithm for Self-Stabilizing Skip Graphs

    E-Print Network [OSTI]

    Richa, Andrea Werneck

    A Distributed Polylogarithmic Time Algorithm for Self-Stabilizing Skip Graphs Riko Jacob Dept. Computer Science Technische Universit√§t M√ľnchen D-85748 Garching bei M√ľnchen, Germany jacob or commercial advantage and that copies bear this notice and the full citation on the first page. To copy

  16. Design and Verification of Instantiable Compliance Rule Graphs in Process-Aware

    E-Print Network [OSTI]

    Pfeifer, Holger

    against imposed compliance rules. Tab. 1 summarizes quality compliance rules imposed on the software. Nevertheless, for quality assurance, it could be desired to verify c2 over the development process. ThusDesign and Verification of Instantiable Compliance Rule Graphs in Process-Aware Information Systems

  17. Predicting Protein Folds with Structural Repeats Using a Chain Graph Model

    E-Print Network [OSTI]

    Xing, Eric P.

    Predicting Protein Folds with Structural Repeats Using a Chain Graph Model Yan Liu yanliu, Carnegie Mellon University, Pittsburgh, PA 15213 USA Abstract Protein fold recognition is a key step to to accurately identify protein folds aris- ing from typical spatial arrangements of well-defined secondary

  18. On covering planar graphs with a fixed number of balls Victor Chepoi, Bertrand Estellon, Yann Vax`es

    E-Print Network [OSTI]

    Chepoi, Victor

    On covering planar graphs with a fixed number of balls Victor Chepoi, Bertrand Estellon, Yann Vax`es¬īediterran¬īee, F-13288 Marseille Cedex 9, France, {chepoi,estellon,vaxes}@lif.univ-mrs.fr Abstract. In this note

  19. Characterization of Trivalent Graphs with Minimal Eigenvalue Gap* Clemens Brand,a Barry Guiduli,b,** and Wilfried Imrichc,***

    E-Print Network [OSTI]

    Babai, László

    Characterization of Trivalent Graphs with Minimal Eigenvalue Gap* Clemens Brand,a Barry Guiduli is the mirror image of one of these blocks. Each interior block is of the type: or (2) We will refer

  20. Lower bounds on the obstacle number of graphs Padmini Mukkamala1, Janos Pach2, and Domotor Palvolgyi3

    E-Print Network [OSTI]

    Pach, J√°nos

    Lower bounds on the obstacle number of graphs Padmini Mukkamala1, J¬īanos Pach2, and D¬®om¬®ot¬®or P are extensively studied and used in computational geometry, robot motion planning, computer vision, sensor

  1. The relationship between graphing calculator use and the development of classroom norms in an exemplay teacher's college algebra course

    E-Print Network [OSTI]

    Gerren, Sally Sue

    2008-10-10T23:59:59.000Z

    to explore the question: What happens when an exemplary teacher uses graphing calculators in a college algebra class? The purposively selected participants were the teacher and eleven students of a Texas community college algebra course. All 29 classes...

  2. Discrete Mathematics and Theoretical Computer Science DMTCS vol. 12:3, 2010, 6374 Covering codes in Sierpinski graphs

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Discrete Mathematics and Theoretical Computer Science DMTCS vol. 12:3, 2010, 63¬≠74 Covering codesth May 2010. For a graph G and integers a and b, an (a, b)-code of G is a set C of vertices. In this paper we classify integers a and b for which there exist (a, b)-codes in Sierpi¬īnski graphs. Keywords

  3. Instability of Bose-Einstein condensation on quantum graphs under repulsive perturbations

    E-Print Network [OSTI]

    Jens Bolte; Joachim Kerner

    2014-11-26T23:59:59.000Z

    In this Note we investigate Bose-Einstein condensation in interacting quantum many-particle systems on graphs. We extend previous results obtained for particles on an interval and show that even arbitrarily small repulsive two-particle interactions destroy a condensate in the non-interacting Bose gas. Our results also cover singular two-particle interactions, such as the well-known Lieb-Lininger model, in the thermodynamic limit.

  4. Dynamic Motion Graphs Bjrn Krger1, Arno Zinke2, Andreas Weber1

    E-Print Network [OSTI]

    Bonn, Universität

    Dynamic Motion Graphs Bj√∂rn Kr√ľger1, Arno Zinke2, Andreas Weber1 1Institute of Computer Science II, University of Bonn 2GfaR mbH, Bonn e-mail: {kruegerb, zinke, weber}@cs.uni-bonn.de Introduction Method result. [KTWZ10] KR√?GER, B., TAUTGES, J., WEBER, A., AND ZINKE, A. Fast local and global similarity

  5. ISOPERIMETRIC CONSTANT OF A k-REGULAR GRAPH (A NOTE ON A THEOREM OF

    E-Print Network [OSTI]

    Smirnova-Nagnibeda, Tatiana

    ISOPERIMETRIC CONSTANT OF A k-REGULAR GRAPH (A NOTE ON A THEOREM OF BIGGS, MOHAR, AND SHAWE.2 in the paper [BMS] of Biggs, Mohar, and Shawe-Taylor we have instead of (1) and (2): i #21; 4(1 #26;) , #26 that #26; #20; q 1 i 2 k 2 . References BMS. N. Biggs, B. Mohar, J. Shawe-Taylor, The spectral radius of in

  6. Efficient Graph Based Assembly of Short-Read Sequences on Hybrid Core Architecture

    SciTech Connect (OSTI)

    Sczyrba, Alex; Pratap, Abhishek; Canon, Shane; Han, James; Copeland, Alex; Wang, Zhong; Brewer, Tony; Soper, David; D'Jamoos, Mike; Collins, Kirby; Vacek, George

    2011-03-22T23:59:59.000Z

    Advanced architectures can deliver dramatically increased throughput for genomics and proteomics applications, reducing time-to-completion in some cases from days to minutes. One such architecture, hybrid-core computing, marries a traditional x86 environment with a reconfigurable coprocessor, based on field programmable gate array (FPGA) technology. In addition to higher throughput, increased performance can fundamentally improve research quality by allowing more accurate, previously impractical approaches. We will discuss the approach used by Convey?s de Bruijn graph constructor for short-read, de-novo assembly. Bioinformatics applications that have random access patterns to large memory spaces, such as graph-based algorithms, experience memory performance limitations on cache-based x86 servers. Convey?s highly parallel memory subsystem allows application-specific logic to simultaneously access 8192 individual words in memory, significantly increasing effective memory bandwidth over cache-based memory systems. Many algorithms, such as Velvet and other de Bruijn graph based, short-read, de-novo assemblers, can greatly benefit from this type of memory architecture. Furthermore, small data type operations (four nucleotides can be represented in two bits) make more efficient use of logic gates than the data types dictated by conventional programming models.JGI is comparing the performance of Convey?s graph constructor and Velvet on both synthetic and real data. We will present preliminary results on memory usage and run time metrics for various data sets with different sizes, from small microbial and fungal genomes to very large cow rumen metagenome. For genomes with references we will also present assembly quality comparisons between the two assemblers.

  7. Memorial University of Newfoundland Department of Mathematics and Statistics Bellman's Algorithm for Acyclic Directed Graphs

    E-Print Network [OSTI]

    deYoung, Brad

    time O(n 2 ). And each iteration of step (3) takes times O(n); with up to n iterations, step (3. A canonical ordering of the vertices is generated by the following algorithm (the output of which is either of a directed graph takes time O(n 2 ). How- ever, the algorithm presented has time O(n 3 ). In step (2), which

  8. Resumes de textes par extraction de phrases, algorithmes de graphe et energie textuelle

    E-Print Network [OSTI]

    San-Juan, Eric

    R¬īesum¬īes de textes par extraction de phrases, algorithmes de graphe et ¬īenergie textuelle Silvia. Lorsqu'il s'agit de r¬īesumer automatiquement une large quantit¬īe de texte, l'approche actuellement la¬īen¬īeralement effectu¬īes sur la matrice mots √? phrases. Le r¬īesum¬īe reprend alors les n phrases les plus lourdes dans l

  9. Experimental investigation of Wigner's reaction matrix for irregular graphs with absorption

    E-Print Network [OSTI]

    Oleh Hul; Oleg Tymoshchuk; Szymon Bauch; Peter M. Koch; Leszek Sirko

    2009-03-12T23:59:59.000Z

    We use tetrahedral microwave networks consisting of coaxial cables and attenuators connected by T-joints to make an experimental study of Wigner's reaction K matrix for irregular graphs in the presence of absorption. From measurements of the scattering matrix S for each realization of the microwave network we obtain distributions of the imaginary and real parts of K. Our experimental results are in good agreement with theoretical predictions.

  10. AGE: a distributed environment for creating interactive animations of graphs

    E-Print Network [OSTI]

    Veatch, Timothy Richard

    1990-01-01T23:59:59.000Z

    com- munication domain. Standard routines, which we shall refer to as the AGE client primitives, that read snd write AGE messages to and from the socket, and routines that create and interpret AGE messages have been developed and are available... for use by those wishing to code a client program (refer to Appendix C). While most requirements for the environment desired are fulfilled by the AGE server, itself, some facilities are supplied by clients, namely, scripts, view broadcasting...

  11. On the Irreps of the N-Extended Supersymmetric Quantum Mechanics and Their Fusion Graphs

    E-Print Network [OSTI]

    Francesco Toppan

    2006-12-27T23:59:59.000Z

    In this talk we review the classification of the irreducible representations of the algebra of the N-extended one-dimensional supersymmetric quantum mechanics presented in hep-th/0511274. We answer some issues raised in hep-th/0611060, proving the agreement of the results here contained with those in hep-th/0511274. We further show that the fusion algebra of the 1D N-extended supersymmetric vacua introduced in hep-th/0511274 admits a graphical presentation. The N=2 graphs are here explicitly presented for the first time.

  12. Some observations on Goldberg-Trajan's Maximum Flow algorithm on Bipartite Graphs

    E-Print Network [OSTI]

    Yang, Bencai

    1997-01-01T23:59:59.000Z

    ) is a direct graph with two distinguished vertices s (the source) and t (the sink). Each edge [u, v] in G is associated with a positive integer cap(u, v), called the capacity of the edge. If there is no edge from vertex u to vertex v. then we define... cap(u, v) = 0. Intuitively, a flow in a flow network should satisfy the following three conditions: (1) the amount of flow along an edge should not exceed the capacity of the edge (capacity constraint); (2) a flow from a vertex u to a vertex v can...

  13. Planning Graph as a (Dynamic) CSP: Exploiting EBL, DDB and other CSP Search Techniques in Graphplan

    E-Print Network [OSTI]

    Kambhampati, S

    2011-01-01T23:59:59.000Z

    This paper reviews the connections between Graphplan's planning-graph and the dynamic constraint satisfaction problem and motivates the need for adapting CSP search techniques to the Graphplan algorithm. It then describes how explanation based learning, dependency directed backtracking, dynamic variable ordering, forward checking, sticky values and random-restart search strategies can be adapted to Graphplan. Empirical results are provided to demonstrate that these augmentations improve Graphplan's performance significantly (up to 1000x speedups) on several benchmark problems. Special attention is paid to the explanation-based learning and dependency directed backtracking techniques as they are empirically found to be most useful in improving the performance of Graphplan.

  14. MadDM v.1.0: Computation of Dark Matter Relic Abundance Using MadGraph5

    E-Print Network [OSTI]

    Mihailo Backovic; Kyoungchul Kong; Mathew McCaskey

    2014-04-24T23:59:59.000Z

    We present MadDM v.1.0, a numerical tool to compute dark matter relic abundance in a generic model. The code is based on the existing MadGraph 5 architecture and as such is easily integrable into any MadGraph collider study. A simple Python interface offers a level of user-friendliness characteristic of MadGraph 5 without sacrificing functionality. MadDM is able to calculate the dark matter relic abundance in models which include a multi-component dark sector, resonance annihilation channels and co-annihilations. We validate the code in a wide range of dark matter models by comparing the relic density results from MadDM to the existing tools and literature.

  15. Experimental and numerical investigation of the reflection coefficient and the distributions of Wigner's reaction matrix for irregular graphs with absorption

    E-Print Network [OSTI]

    Michal Lawniczak; Oleh Hul; Szymon Bauch; Petr Seba; Leszek Sirko

    2009-03-18T23:59:59.000Z

    We present the results of experimental and numerical study of the distribution of the reflection coefficient P(R) and the distributions of the imaginary P(v) and the real P(u) parts of the Wigner's reaction K matrix for irregular fully connected hexagon networks (graphs) in the presence of strong absorption. In the experiment we used microwave networks, which were built of coaxial cables and attenuators connected by joints. In the numerical calculations experimental networks were described by quantum fully connected hexagon graphs. The presence of absorption introduced by attenuators was modelled by optical potentials. The distribution of the reflection coefficient P(R) and the distributions of the reaction K matrix were obtained from the measurements and numerical calculations of the scattering matrix S of the networks and graphs, respectively. We show that the experimental and numerical results are in good agreement with the exact analytic ones obtained within the framework of random matrix theory (RMT).

  16. A preliminary version appeared in Advances in Cryptology --Asiacrypt'02. This is a revised version. The Provable Security of GraphBased OneTime Signatures and

    E-Print Network [OSTI]

    Hevia, Alejandro

    A preliminary version appeared in Advances in Cryptology -- Asiacrypt'02. This is a revised version based on ``graphs of one≠way functions''. Bleichen≠ bacher and Maurer thoroughly analyze graph based . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 3 The GBOTS construction 7 4 The Reduction 8 4.1 Inverting H

  17. A preliminary version appeared in Advances in Cryptology Asiacrypt'02. This is a revised version. The Provable Security of Graph-Based One-Time Signatures and

    E-Print Network [OSTI]

    Hevia, Alejandro

    A preliminary version appeared in Advances in Cryptology ≠ Asiacrypt'02. This is a revised version based on "graphs of one-way functions". Bleichen- bacher and Maurer thoroughly analyze graph based . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 3 The GBOTS construction 7 4 The Reduction 8 4.1 Inverting H

  18. Sharpness of the phase transition and exponential decay of the subcritical cluster size for percolation on quasi-transitive graphs

    E-Print Network [OSTI]

    Ton?i Antunovi?; Ivan Veseli?

    2007-11-12T23:59:59.000Z

    We study homogeneous, independent percolation on general quasi-transitive graphs. We prove that in the disorder regime where all clusters are finite almost surely, in fact the expectation of the cluster size is finite. This extends a well-known theorem by Menshikov and Aizenman & Barsky to all quasi-transitive graphs. Moreover we deduce that in this disorder regime the cluster size distribution decays exponentially, extending a result of Aizenman & Newman. Our results apply to both edge and site percolation, as well as long range (edge) percolation. The proof is based on a modification of the Aizenman & Barsky method.

  19. Mathematical Proofs of Two Conjectures: The Four Color Problem and The Uniquely 4-colorable Planar Graph

    E-Print Network [OSTI]

    Jin Xu

    2012-01-18T23:59:59.000Z

    The famous four color theorem states that for all planar graphs, every vertex can be assigned one of 4 colors such that no two adjacent vertices receive the same color. Since Francis Guthrie first conjectured it in 1852, it is until 1976 with electronic computer that Appel and Haken first gave a proof by finding and verifying 1936 reducible unavoidable sets, and a simplified proof of Robertson, Sanders, Seymour and Thomas in 1997 only involved 633 reducible unavoidable sets, both proofs could not be realized effectively by hand. Until now, finding the reducible unavoidable sets remains the only successful method to use, which came from Kempe's first "proof" of the four color problem in 1879. An alternative method only involving 4 reducible unavoidable sets for proving the four color theorem is used in this paper, which takes form of mathematical proof rather than a computer-assisted proof and proves both the four color conjecture and the uniquely 4-colorable planar graph conjecture by mathematical method.

  20. Pattern analysis of directed graphs using DEDICOM: an application to Enron email.

    SciTech Connect (OSTI)

    Bader, Brett William; Harshman, Richard A. (University of Western Ontario London, Ontario, Canada); Kolda, Tamara Gibson (Sandia National Labs, Livermore, CA)

    2006-12-01T23:59:59.000Z

    DEDICOM is a linear algebra model for analyzing intrinsically asymmetric relationships, such as trade among nations or the exchange of emails among individuals. DEDICOM decomposes a complex pattern of observed relations among objects into a sum of simpler patterns of inferred relations among latent components of the objects. Three-way DEDICOM is a higher-order extension of the model that incorporates a third mode of the data, such as time, giving it stronger uniqueness properties and consequently enhancing interpretability of solutions. In this paper, we present algorithms for computing these decompositions on large, sparse data as well as a variant for computing an asymmetric nonnegative factorization. When we apply these techniques to adjacency arrays arising from directed graphs with edges labeled by time, we obtain a smaller graph on latent semantic dimensions and gain additional information about their changing relationships over time. We demonstrate these techniques on the Enron email corpus to learn about the social networks and their transient behavior. The mixture of roles assigned to individuals by DEDICOM showed strong correspondence with known job classifications and revealed the patterns of communication between these roles. Changes in the communication pattern over time, e.g., between top executives and the legal department, were also apparent in the solutions.

  1. GeoTriples: a Tool for Publishing Geospatial Data as RDF Graphs Using R2RML Mappings

    E-Print Network [OSTI]

    Koubarakis, Manolis

    GeoTriples: a Tool for Publishing Geospatial Data as RDF Graphs Using R2RML Mappings Kostis the tool GeoTriples that allows the transformation of Earth Observation data and geospatial data into RDF of geospatial data. GeoTriples is a semi- automated tool that transforms geospatial information into RDF follow

  2. Introduction to Network Science 1 Spectral Methods (aka Algebraic Graph Theory, see Chapter 14 in [BE] "Network analysis")

    E-Print Network [OSTI]

    Safro, Ilya

    Introduction to Network Science 1 Spectral Methods (aka Algebraic Graph Theory, see Chapter 14 #12;Introduction to Network Science 2 #12;Introduction to Network Science 3 Homework: Prove any 2 out of 3 in Theorem 3 (submit by 3/6/2014) #12;Introduction to Network Science 4 There exists some nonzero

  3. Introduction to Network Analysis 1 Spectral Methods (aka Algebraic Graph Theory, see Chapter 14 in *BE+ "Network analysis")

    E-Print Network [OSTI]

    Safro, Ilya

    Introduction to Network Analysis 1 Spectral Methods (aka Algebraic Graph Theory, see Chapter 14 in *BE+ "Network analysis") Three main objects of interest: adjacency matrix, Laplacian, and normalized to Network Analysis 12 original reverse Cuthill-McKee spectral Matlab demo #12;Introduction to Network

  4. To be published in Computers & Graphics, vol. 28, no. 6, 2004. Point Cloud Surfaces using Geometric Proximity Graphs

    E-Print Network [OSTI]

    Behnke, Sven

    Proximity Graphs Jan Klein a and Gabriel Zachmann b aHeinz Nixdorf Institute and Institute of Computer@cs.uni-bonn.de (Gabriel Zachmann). In this paper, we present a new definition of a surface over a given point cloud

  5. To be published in Computers & Graphics, vol. 28, no. 6, 2004. Point Cloud Surfaces using Geometric Proximity Graphs

    E-Print Network [OSTI]

    Zachmann, Gabriel

    Proximity Graphs Jan Klein a and Gabriel Zachmann b a Heinz Nixdorf Institute and Institute of Computer@cs.uni­bonn.de (Gabriel Zachmann). In this paper, we present a new definition of a surface over a given point cloud

  6. Approximate inference on planar graphs using loop calculus and belief progagation

    SciTech Connect (OSTI)

    Chertkov, Michael [Los Alamos National Laboratory; Gomez, Vicenc [RADBOUD UNIV; Kappen, Hilbert [RADBOUD UNIV

    2009-01-01T23:59:59.000Z

    We introduce novel results for approximate inference on planar graphical models using the loop calculus framework. The loop calculus (Chertkov and Chernyak, 2006b) allows to express the exact partition function Z of a graphical model as a finite sum of terms that can be evaluated once the belief propagation (BP) solution is known. In general, full summation over all correction terms is intractable. We develop an algorithm for the approach presented in Chertkov et al. (2008) which represents an efficient truncation scheme on planar graphs and a new representation of the series in terms of Pfaffians of matrices. We analyze in detail both the loop series and the Pfaffian series for models with binary variables and pairwise interactions, and show that the first term of the Pfaffian series can provide very accurate approximations. The algorithm outperforms previous truncation schemes of the loop series and is competitive with other state-of-the-art methods for approximate inference.

  7. Eigenfunctions of Unbounded Support for Embedded Eigenvalues of Locally Perturbed Periodic Graph Operators

    E-Print Network [OSTI]

    Stephen P. Shipman

    2014-04-24T23:59:59.000Z

    It is known that, if a locally perturbed periodic self-adjoint operator on a combinatorial or quantum graph admits an eigenvalue embedded in the continuous spectrum, then the associated eigenfunction is compactly supported--that is, if the Fermi surface is irreducible, which occurs generically in dimension two or higher. This article constructs a class of operators whose Fermi surface is reducible for all energies by coupling several periodic systems. The components of the Fermi surface correspond to decoupled spaces of hybrid states, and in certain frequency bands, some components contribute oscillatory hybrid states (corresponding to spectrum) and other components contribute only exponential ones. This separation allows a localized defect to suppress the oscillatory (radiation) modes and retain the evanescent ones, thereby leading to embedded eigenvalues whose associated eigenfunctions decay exponentially but are not compactly supported.

  8. Understanding resonance graphs using Easy Java Simulations (EJS) and why we use EJS

    E-Print Network [OSTI]

    Wee, Loo Kang; Chew, Charles; Wong, Darren; Tan, Samuel

    2015-01-01T23:59:59.000Z

    This paper reports a computer model- simulation created using Easy Java Simulation (EJS) for learners to visualize how the steady-state amplitude of a driven oscillating system varies with the frequency of the periodic driving force. The simulation shows (N=100) identical spring-mass systems being subjected to (1) periodic driving force of equal amplitude but different driving frequencies and (2) different amount of damping. The simulation aims to create a visually intuitive way of understanding how the series of amplitude versus driving frequency graphs are obtained by showing how the displacement of the system changes over time as it transits from the transient to the steady state. A suggested how to use the model is added to help educators and students in their teaching and learning, where we explained the theoretical steady state equation, time conditions when the model starts allowing data recording of maximum amplitudes to closely match the theoretical equation and steps to collect different runs of deg...

  9. Parallel Chip-Firing on the Complete Graph: Devil's Staircase and Poincare Rotation Number

    E-Print Network [OSTI]

    Levine, Lionel

    2008-01-01T23:59:59.000Z

    We study how parallel chip-firing on the complete graph K_n changes behavior as we vary the total number of chips. Surprisingly, the activity of the system, defined as the average number of firings per time step, does not increase smoothly in the number of chips; instead it remains constant over long intervals, punctuated by sudden jumps. In the large n limit we find a "devil's staircase" dependence of activity on the number of chips. The proof proceeds by reducing the chip-firing dynamics to iteration of a self-map of the circle S^1, in such a way that the activity of the chip-firing state equals the Poincare rotation number of the circle map. The stairs of the devil's staircase correspond to periodic chip-firing states of small period.

  10. Designing a graph-based approach to landscape ecological assessment of linear infrastructures

    SciTech Connect (OSTI)

    Girardet, Xavier, E-mail: xavier.girardet@univ-fcomte.fr; FoltÍte, Jean-Christophe, E-mail: jean-christophe.foltete@univ-fcomte.fr; Clauzel, Cťline, E-mail: celine.clauzel@univ-fcomte.fr

    2013-09-15T23:59:59.000Z

    The development of major linear infrastructures contributes to landscape fragmentation and impacts natural habitats and biodiversity in various ways. To anticipate and minimize such impacts, landscape planning needs to be capable of effective strategic environmental assessment (SEA) and of supporting environmental impact assessment (EIA) decisions. To this end, species distribution models (SDMs) are an effective way of making predictive maps of the presence of a given species. In this paper, we propose to combine SDMs and graph-based representation of landscape networks to integrate the potential long-distance effect of infrastructures on species distribution. A diachronic approach, comparing distribution before and after the linear infrastructure is constructed, leads to the design of a species distribution assessment (SDA), taking into account population isolation. The SDA makes it possible (1) to estimate the local variation in probability of presence and (2) to characterize the impact of the infrastructure in terms of global variation in presence and of distance of disturbance. The method is illustrated by assessing the impact of the construction of a high-speed railway line on the distribution of several virtual species in Franche-Comtť (France). The study shows the capacity of the SDA to characterize the impact of a linear infrastructure either as a research concern or as a spatial planning challenge. SDAs could be helpful in deciding among several scenarios for linear infrastructure routes or for the location of mitigation measures. -- Highlights: ē Graph connectivity metrics were integrated into a species distribution model. ē SDM was performed before and after the implementation of linear infrastructure. ē The local variation of presence provides spatial indicators of the impact.

  11. Bifurcations and stability of standing waves in the nonlinear SchrŲdinger equation on the tadpole graph

    E-Print Network [OSTI]

    Diego Noja; Dmitry Pelinovsky; Gaukhar Shaikhova

    2014-12-28T23:59:59.000Z

    We develop a detailed rigorous analysis of edge bifurcations of standing waves in the nonlinear Schr\\"odinger (NLS) equation on a tadpole graph (a ring attached to a semi-infinite line subject to the Kirchhoff boundary conditions at the junction). It is shown in the recent work [7] by using explicit Jacobi elliptic functions that the cubic NLS equation on a tadpole graph admits a rich structure of standing waves. Among these, there are different branches of localized waves bifurcating from the edge of the essential spectrum of an associated Schr\\"odinger operator. We show by using a modified Lyapunov-Schmidt reduction method that the bifur- cation of localized standing waves occurs for every positive power nonlinearity. We distinguish a primary branch of never vanishing standing waves bifurcating from the trivial solution and an infinite sequence of higher branches with oscillating behavior in the ring. The higher branches bifurcate from the branches of degenerate standing waves with vanishing tail outside the ring. Moreover, we analyze stability of bifurcating standing waves. Namely, we show that the primary branch is composed by orbitally stable standing waves for subcritical power nonlinearities, while all nontrivial higher branches are linearly unstable near the bifurcation point. The stability character of the degenerate branches remains inconclusive at the analytical level, whereas heuristic arguments based on analysis of embedded eigenvalues of negative Krein signatures support the conjecture of their linear instability at least near the bifurcation point. Numerical results for the cubic NLS equation show that this conjecture is valid and that the degenerate branches become spectrally stable far away from the bifurcation point.

  12. Retracts of products of chordal graphs B. Bresar1, J. Chalopin2, V. Chepoi2, M. Kovse1, A. Labourel2, and Y. Vax`es2

    E-Print Network [OSTI]

    Chepoi, Victor

    2, and Y. Vax`es2 1Faculty of Natural Sciences and Mathematics University of Maribor, Koroska cesta {chalopin,chepoi,labourel,vaxes}@lif.univ-mrs.fr Abstract. In this note, we characterize the graphs G

  13. Relating Doubly-Even Error-Correcting Codes, Graphs, and Irreducible Representations of N-Extended Supersymmetry

    E-Print Network [OSTI]

    C. F. Doran; M. G. Faux; S. J. Gates Jr; T. Hubsch; K. M. Iga; G. D. Landweber

    2008-05-31T23:59:59.000Z

    Previous work has shown that the classification of indecomposable off-shell representations of N-supersymmetry, depicted as Adinkras, may be factored into specifying the topologies available to Adinkras, and then the height-assignments for each topological type. The latter problem being solved by a recursive mechanism that generates all height-assignments within a topology, it remains to classify the former. Herein we show that this problem is equivalent to classifying certain (1) graphs and (2) error-correcting codes.

  14. $K$-theory and homotopies of 2-cocycles on higher-rank graphs.

    E-Print Network [OSTI]

    Elizabeth Gillaspy

    This paper continues our investigation into the question of when a homotopy $\\omega = {\\omega_t}_{t \\in [0,1]}$ of 2-cocycles on a locally compact Hausdorff groupoid $\\mathcal{G}$ gives rise to an isomorphism of the $K$-theory groups of the twisted groupoid $C^*$-algebras: $K_*(C^*(\\mathcal{G}, \\omega_0)) \\cong K_*(C^*(\\mathcal{G}, \\omega_1)).$ In particular, we build on work by Kumjian, Pask, and Sims to show that if $\\mathcal{G} = \\mathcal{G}_\\Lambda$ is the infinite path groupoid associated to a row-finite higher-rank graph $\\Lambda$ with no sources, and ${c_t}_{t \\in [0,1]}$ is a homotopy of 2-cocycles on $\\Lambda$, then $K_*(C^*(\\mathcal{G}_\\Lambda, \\sigma_{c_0})) \\cong K_*(C^*(\\mathcal{G}_\\Lambda, \\sigma_{c_1})),$ where $\\sigma_{c_t}$ denotes the 2-cocycle on $\\mathcal{G}_\\Lambda$ associated to the 2-cocycle $c_t$ on $\\Lambda$. We also prove a technical result (Theorem 3.5), namely that a homotopy of 2-cocycles on a locally compact Hausdorff groupoid $\\mathcal{G}$ gives rise to an upper semi-continuous $C^*$-bundle.

  15. Complete-Graph Tensor Network States: A New Fermionic Wave Function Ansatz for Molecules

    E-Print Network [OSTI]

    Konrad H Marti; Bela Bauer; Markus Reiher; Matthias Troyer; Frank Verstraete

    2010-04-29T23:59:59.000Z

    We present a new class of tensor network states that are specifically designed to capture the electron correlation of a molecule of arbitrary structure. In this ansatz, the electronic wave function is represented by a Complete-Graph Tensor Network (CGTN) ansatz which implements an efficient reduction of the number of variational parameters by breaking down the complexity of the high-dimensional coefficient tensor of a full-configuration-interaction (FCI) wave function. We demonstrate that CGTN states approximate ground states of molecules accurately by comparison of the CGTN and FCI expansion coefficients. The CGTN parametrization is not biased towards any reference configuration in contrast to many standard quantum chemical methods. This feature allows one to obtain accurate relative energies between CGTN states which is central to molecular physics and chemistry. We discuss the implications for quantum chemistry and focus on the spin-state problem. Our CGTN approach is applied to the energy splitting of states of different spin for methylene and the strongly correlated ozone molecule at a transition state structure. The parameters of the tensor network ansatz are variationally optimized by means of a parallel-tempering Monte Carlo algorithm.

  16. Graph-theoretic analysis of discrete-phase-space states for condition change detection and quantification of information

    SciTech Connect (OSTI)

    Hively, Lee M.

    2014-09-16T23:59:59.000Z

    Data collected from devices and human condition may be used to forewarn of critical events such as machine/structural failure or events from brain/heart wave data stroke. By monitoring the data, and determining what values are indicative of a failure forewarning, one can provide adequate notice of the impending failure in order to take preventive measures. This disclosure teaches a computer-based method to convert dynamical numeric data representing physical objects (unstructured data) into discrete-phase-space states, and hence into a graph (structured data) for extraction of condition change.

  17. arXiv:1104.0081v2[math.CO]4Apr2011 CAYLEY GRAPHS OF ORDER 16p ARE HAMILTONIAN

    E-Print Network [OSTI]

    Morris, Joy

    is prime. We show that if S is any generating set of G, then there is a hamiltonian cycle.2(1) of [10]. Namely, several of the main results of that paper combine to show: Every connected Cayley graph on G has a hamiltonian cycle if |G| = kp, where p is prime, 1 k

  18. The Twelfth IEEE International Conference on Computer Vision, Kyoto, Japan. September 27 -October 4, 2009. Higher-Order Gradient Descent by Fusion-Move Graph Cut

    E-Print Network [OSTI]

    Ishikawa, Hiroshi

    , us- ing the reduction[6, 14] then available. The more recent reduction[10] for energies of even 4, 2009. Higher-Order Gradient Descent by Fusion-Move Graph Cut Hiroshi Ishikawa Nagoya City) the fusion move algorithm, ii) the reduction of higher-order binary energy minimization to first

  19. The graphs at right show overall variability distribution estimated for the Pentium D 800 series (near) and the T1 Niagara (far) using the FPGA data

    E-Print Network [OSTI]

    Renau, Jose

    RESULTS The graphs at right show overall variability distribution estimated for the Pentium D 800 where a core no longer works properly. In the Sun T1 Niagara cores this is done with a built-in- self processors we record the temperature at which the failure occurred and adjust to the frequencies

  20. Design and analysis of algorithms and data structures for the efficient solution of graph theoretic problems on MIMD computers

    SciTech Connect (OSTI)

    Quinn, M.J.

    1983-01-01T23:59:59.000Z

    The problem of developing efficient algorithms and data structures to solve graph theoretic problems on tightly-coupled MIMD comuters is addressed. Several approaches to parallelizing a serial algorithm are examined. A technique is developed which allows the prediction of the expected execution time of some kinds of parallel algorithms. This technique can be used to determine which parallel algorithm is best for a particular application. Two parallel approximate algorithms for the Euclidean traveling salesman problem are designed and analyzed. The algorithms are parallelizations of the farthest-insertion heuristic and Karp's partitioning algorithm. Software lockout, the delay of processes due to contention for shared data structure, can be a significant hindrance to obtaining satisfactory speedup. Using the tactics of indirection and replication, new data structures are devised which can reduce the severity of software lockout. Finally, an upper bound to the speedup of parallel branch-and-bound algorithms which use the best-bound search strategy is determined.

  1. The Need to Support of Data Flow Graph Visualization of Forensic Lucid Programs, Forensic Evidence, and their Evaluation by GIPSY

    E-Print Network [OSTI]

    Mokhov, Serguei A; Debbabi, Mourad

    2010-01-01T23:59:59.000Z

    Lucid programs are data-flow programs and can be visually represented as data flow graphs (DFGs) and composed visually. Forensic Lucid, a Lucid dialect, is a language to specify and reason about cyberforensics cases. It includes the encoding of the evidence (representing the context of evaluation) and the crime scene modeling in order to validate claims against the model and perform event reconstruction, potentially within large swaths of digital evidence. To aid investigators to model the scene and evaluate it, instead of typing a Forensic Lucid program, we propose to expand the design and implementation of the Lucid DFG programming onto Forensic Lucid case modeling and specification to enhance the usability of the language and the system.

  2. L-RCM: a method to detect connected components in undirected graphs by using the Laplacian matrix and the RCM algorithm

    E-Print Network [OSTI]

    Pedroche, Francisco; Carrascosa, Carlos; Palomares, Alberto

    2012-01-01T23:59:59.000Z

    In this paper we consider undirected graphs with no loops and multiple edges, consisting of k connected components. In these cases, it is well known that one can find a numbering of the vertices such that the adjacency matrix A is block diagonal with k blocks. This also holds for the (unnormalized) Laplacian matrix L= D-A, with D a diagonal matrix with the degrees of the nodes. In this paper we propose to use the Reverse Cuthill-McKee (RCM) algorithm to obtain a block diagonal form of L that reveals the number of connected components of the graph. We present some theoretical results about the irreducibility of the Laplacian matrix ordered by the RCM algorithm. As a practical application we present a very efficient method to detect connected components with a computational cost of O(m+n), being m the number of edges and n the number of nodes. The RCM method is implemented in some comercial packages like MATLAB and Mathematica. We make the computations by using the function symrcm of MATLAB. Some numerical resu...

  3. Graph algorithms experimentation facility

    E-Print Network [OSTI]

    Sonom, Donald George

    1994-01-01T23:59:59.000Z

    DRAWADJMAT 2 ~e ~l 2. ~f ~2 2 ~t ~& [g H 2 O? Z Mwd a P d ed d Aid~a sae R 2-BE& T C dbms Fig. 2. External Algorithm Handler The facility is menu driven and implemented as a client to XAGE. Our implementation follows very closely the functionality...

  4. Graphs, Strings, and Actions

    E-Print Network [OSTI]

    2010-04-01T23:59:59.000Z

    c© Springer Science+Business Media, LLC 2009 ...... [MS1] J. E. McClure and J. H. Smith. A solution of ... [MS3] James E. McClure and Jeffrey H. Smith.

  5. PDSF Utilization Graphs

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLas Conchas recoveryLaboratorySpeedingOptimizingTools Software and Tools Chos Chos is used

  6. AN ASPECT OF A DIDACTICAL PATH FOR APPROACHING THE CONCEPT OF FUNCTION: THE QUALITATIVE INTERPRETATION OF A GRAPH

    E-Print Network [OSTI]

    Spagnolo, Filippo

    156 AN ASPECT OF A DIDACTICAL PATH FOR APPROACHING THE CONCEPT OF FUNCTION: THE QUALITATIVE uncertainties and difficulties when teaching it (Even, 1993). At the middle school level, it seems didactically and their representations. From a didactical point of view, this sets the problem of how to lead the student to put

  7. Digitizer Auditory Graph: Making Graphs Accessible to the Visually

    E-Print Network [OSTI]

    .2 Social Issues: Assistive technologies for persons with disabilities Copyright is held by the author 30332 USA heejoong@gatech.edu Bruce N. Walker Sonification Lab, Schools of Psychology and Interactive Computing Georgia Institute of Technology 654 Cherry St. Atlanta, GA 30332 USA bruce

  8. Presented by Scalable Graph Decompositions

    E-Print Network [OSTI]

    Approach #12;4 Managed by UT-Battelle for the U.S. Department of Energy Sullivan_MapD_SC10 Tree by UT-Battelle for the U.S. Department of Energy Sullivan_MapD_SC10 Finding a tree decomposition · Tree.S. Department of Energy Sullivan_MapD_SC10 Yeast Protein Interaction Network Motivation · Massive data

  9. Graphs in R and Bioconductor

    E-Print Network [OSTI]

    Spang, Rainer

    biggest: size ~ log(n)). degrees of separation: log(n). Erdös and Rényi 1960 #12;Small worlds Clustering networks - scientific collaboration networks - WWW - company ownership in Germany - ,,6 degrees of Kevin

  10. HLTNAACL 06 TextGraphs

    E-Print Network [OSTI]

    Radev, Dragomir R.

    of the Workshop #12; Production and Manufacturing by Omnipress Inc. 2600 Anderson Street Madison, WI 53704 c #2006 of confidence provided by her quick and enthusiastic acceptance. Rada Mihalcea and Dragomir Radev June 2006 iii, Cornell University Patrick Pantel, USC / Information Sciences Institute Paul Tarau, University of North

  11. Automatic Online Haptic Graph Construction

    E-Print Network [OSTI]

    Yu, W.; Cheung, K.; Brewster, S.A.

    Yu,W. Cheung,K. Brewster,S.A. In Proceedings of Eurohaptics 2002 (Edinburgh, UK), Edinburgh University pp 128-133 Academic Press

  12. Graph regularization methods for Web spam detection

    E-Print Network [OSTI]

    Abernethy, Jacob; Chapelle, Olivier; Castillo, Carlos

    2010-01-01T23:59:59.000Z

    An introduction to the conjugate gradient method without theonly implemented the conjugate gradient method. Note onemployed was the conjugate gradient method, de- scribed in

  13. Support graph preconditioners for sparse linear systems

    E-Print Network [OSTI]

    Gupta, Radhika

    2005-02-17T23:59:59.000Z

    Elliptic partial differential equations that are used to model physical phenomena give rise to large sparse linear systems. Such systems can be symmetric positive de?nite and can be solved by the preconditioned conjugate gradients method...

  14. Continuous Control in Buildings with Bond Graphs

    E-Print Network [OSTI]

    Zeiler, W.

    2011-01-01T23:59:59.000Z

    and reductions in room air mixing, International conference on Environmental Ergonomics August 2-7. Zhang H., Arens E., Huizinga C., Han T., 2010, Thermal sensations and comfort models for non- uniform and transient environments, Building and Environment...

  15. Graph Transformation with Focus on Incident Edges

    E-Print Network [OSTI]

    Duval, Dominique

    such as the sesqui-pushout, the heterogeneous pushout and the adaptive star grammars approaches. We first define-called shallow cloning [15] or deep cloning [20] operations). Informally, by cloning a node n, we mean making funded by the project CLIMT of the French Agence Nationale de la Recherche (ANR-11-BS02-016). #12;(Sq

  16. A Parallel Graph Partitioner for STAPL

    E-Print Network [OSTI]

    Castet, Nicolas

    2013-04-26T23:59:59.000Z

    difficult task for programmers. They need to deal with low-level parallel mechanisms such as data distribution, inter-processor communication, and task placement. The goal of the Standard Template Adaptive Parallel Library (STAPL) is to provide a generic...

  17. HLT-NAACL 06 TextGraphs

    E-Print Network [OSTI]

    Radev, Dragomir R.

    of the Workshop #12;Production and Manufacturing by Omnipress Inc. 2600 Anderson Street Madison, WI 53704 c 2006 of confidence provided by her quick and enthusiastic acceptance. Rada Mihalcea and Dragomir Radev June 2006 iii, Cornell University Patrick Pantel, USC / Information Sciences Institute Paul Tarau, University of North

  18. Analysis of Link Graph Compression Techniques

    E-Print Network [OSTI]

    Hannah, D.; Macdonald, C.; Ounis, I.

    Hannah,D. Macdonald,C. Ounis,I. In Proceedings of the 30th European Conference on Information Retrieval (ECIR 2008), Glasgow, 30th March - 3rd April 2008. LNCS, Springer

  19. Convex Optimization of Graph Laplacian Eigenvalues

    E-Print Network [OSTI]

    with Persi Diaconis, Arpita Ghosh, Seung-Jean Kim, Sanjay Lall, Pablo Parrilo, Amin Saberi, Jun Sun, Lin Xiao

  20. Diffusion and clustering on large graphs

    E-Print Network [OSTI]

    Tsiatas, Alexander

    2012-01-01T23:59:59.000Z

    Jennifer Chayes, and Amin Saberi. ďOn the spread of virusesGanesh, and Amin Saberi. ďHow to distribute antidote toMontanari and Amin Saberi. ďConvergence to equilibrium in

  1. Convex Optimization of Graph Laplacian Eigenvalues

    E-Print Network [OSTI]

    Persi Diaconis, Arpita Ghosh, Seung-Jean Kim, Sanjay Lall, Pablo Parrilo, Amin Saberi. Jun Sun, and Lin

  2. Covering Graphs with Few Complete Bipartite Subgraphs

    E-Print Network [OSTI]

    Paulusma, Daniel

    Vienna, Austria fleisch@dbai.tuwien.ac.at 2 Mathematics Department, University of Dar es Salaam PO Box 35062, Dar es Salaam, Tanzania emujuni@maths.udsm.ac.tz 3 Department of Computer Science, Durham

  3. A Spectral Algorithm for Improving Graph Partitions

    E-Print Network [OSTI]

    2009-12-03T23:59:59.000Z

    Dec 3, 2009 ... G to bias it towards this vector, and use this relaxation to present a new ...... extracted from it, we see that the resulting voltages must exactly†...

  4. Detecting Network Vulnerabilities Through Graph Theoretical Methods

    E-Print Network [OSTI]

    Geddes, Cameron Guy Robinson

    vulnerabilities in power networks is an important prob- lem, as even a small number of vulnerable connections can benchmark power networks. 1 Introduction The electric power grid network is susceptible to power outages northeast and Canada, which affected an estimated 50 million people, causing over $6 billion in damage

  5. BASSET: Scalable Gateway Finder in Large Graphs

    SciTech Connect (OSTI)

    Tong, H; Papadimitriou, S; Faloutsos, C; Yu, P S; Eliassi-Rad, T

    2010-11-03T23:59:59.000Z

    Given a social network, who is the best person to introduce you to, say, Chris Ferguson, the poker champion? Or, given a network of people and skills, who is the best person to help you learn about, say, wavelets? The goal is to find a small group of 'gateways': persons who are close enough to us, as well as close enough to the target (person, or skill) or, in other words, are crucial in connecting us to the target. The main contributions are the following: (a) we show how to formulate this problem precisely; (b) we show that it is sub-modular and thus it can be solved near-optimally; (c) we give fast, scalable algorithms to find such gateways. Experiments on real data sets validate the effectiveness and efficiency of the proposed methods, achieving up to 6,000,000x speedup.

  6. Evolutionary Design of Objects Using Scene Graphs

    E-Print Network [OSTI]

    Ebner, Marc

    for the evolution of a wind turbine. The VRML representation produced better results. 1 Motivation Evolutionary of di#11;erent representations have been used in evolutionary design. They range from direct encoding

  7. Graph-Theoretic Connectivity Control of Mobile

    E-Print Network [OSTI]

    Pappas, George J.

    exploration, surveillance, and recon- naissance, to cooperative construction and manipulation. The success]­[23]. This research has given rise to connectivity or topology control algorithms that regulate the transmission power is with the Department of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA 30332 USA (e

  8. Detecting Network Vulnerabilities Through Graph Theoretical Methods

    E-Print Network [OSTI]

    2007-01-01T23:59:59.000Z

    a signi?cant linear relationship between generator size andof those generators. We performed simple linear regression

  9. Graphs from Volume 1 Book 2

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation ProposedUsingFun with Big Sky LearningGetGraphene's 3D Counterpart Print1, 2009Ôāó We want

  10. OpenEI Community - Visualization Graph

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 No revision hasInformation Earth'sOklahoma/Geothermal < Oklahomast, 2012Coast Utilities prepare

  11. On Grids in Topological Graphs Eyal Ackerman

    E-Print Network [OSTI]

    Pach, J√°nos

    Berlin Takustr. 9, 14195 Berlin, Germany eyal@inf.fu-berlin.de Jacob Fox Department of Mathematics or distributed for profit or commercial advantage and that copies bear this notice and the full citation

  12. Single View Human Action Recognition using Key Pose Matching and Viterbi Path Searching

    E-Print Network [OSTI]

    Southern California, University of

    by a graph model called Action Net. Given the input, silhouette matching be- tween the input frames representation scheme called Action Net. Action Net is a graph model. Each node in the Action Net contains the 2D the essence of each action class even if there is variance in execution styles of the same action. The Action

  13. Surface Reconstruction with Feature Preservation based on Graph-cuts

    E-Print Network [OSTI]

    Soatto, Stefano

    features. The effectiveness of the weighted minimal surface model E(S) is examined in the tetrahedral mesh is a very close approximation to the global minimum of EC (S). Various examples show the effectiveness Sciences, Nanyang Technological University, Singapore 637371. E-mail: wanm0003@e.ntu.edu.sg, {desheng,xctai}@ntu

  14. Decoding linear codes via optimization and graph-based techniques

    E-Print Network [OSTI]

    Taghavi, Mohammad H.

    2008-01-01T23:59:59.000Z

    including the conjugate-gradient method, have a slowsuch as the conjugate-gradient (CG) method, that are oftenpreconditioned conjugate gradient (PCG) method for solving

  15. GraphBased Authentication of Digital Streams Sara Miner

    E-Print Network [OSTI]

    @cs.ucsd.edu Jessica Staddon y Xerox Palo Alto Research Center 3333 Coyote Hill Road Palo Alto, CA 94304 jstaddon@parc the secret as a key for a message authentica­ tion code (MAC), then MAC the content in each packet

  16. NP-Hardness of the Bandwidth Problem on Dense Graphs

    E-Print Network [OSTI]

    Eckmiller, Rolf

    , know, do, of, is, me, in, just, be, was, with, that, this, for, my, on, think, im, what, up, not, we 2

  17. Bounds for the Online Multicast Problem in Directed Graphs

    E-Print Network [OSTI]

    Faloutsos, Michalis

    with polynomial complexity. \\Lambda Designated Contact Author. E­mail: mfalou@cs.toronto.edu. Telephone: +416­978­5182

  18. DISS. ETH NO. 16256, 2005 Games on Graphs

    E-Print Network [OSTI]

    Stojakovic, Milos

    Science, University of Novi Sad, Serbia and Montenegro born August 26, 1976 citizen of Serbia and Montenegro accepted on the recommendation of Prof. Dr. Emo Welzl, ETH Zurich, examiner Dr. Tibor Szab¬īo, ETH

  19. Computing the Grothendieck constant of some graph classes

    E-Print Network [OSTI]

    Monique Laurent

    2011-06-10T23:59:59.000Z

    Jun 10, 2011 ... However this is not the case for the clique-web inequalities, a wide class of valid inequalities for the cut polytope, whose integrality ratio is†...

  20. Computing the Grothendieck constant of some graph classes

    E-Print Network [OSTI]

    2011-06-10T23:59:59.000Z

    Jun 10, 2011 ... However this is not the case for the clique-web inequalities, ... Keywords: Grothendieck constant, elliptope, cut polytope, clique-web inequality.

  1. Monitoring Business Process Compliance Using Compliance Rule Graphs

    E-Print Network [OSTI]

    Ulm, Universität

    processes. Finally, collections of quality controls, e.g., Six Sigma or ITIL, are of particular impor- tance

  2. Design Guidelines for Audio Presentation of Graphs and Tables

    E-Print Network [OSTI]

    Brown, L.M.; Brewster, S.A.

    Brown,L.M. Brewster,S.A. Ramloll,R. Burton,M. Riedel,B. ICAD 2003 Workshop on Auditory Displays In Assistive Technologies, Boston, M.A. International Conference on Auditory Display

  3. Introduction In 1975, Noy-Meir presented a comprehensive, graph-

    E-Print Network [OSTI]

    Schwinning, Susan - Department of Biology, Texas State University

    equilibria (i.e. states of zero net cha; Parsons & Chapman 1998). This simple calculation illustrates that grazed grassland is necessarily

  4. Bounds and Algorithms for the Knapsack Problem with Conflict Graph

    E-Print Network [OSTI]

    2014-06-19T23:59:59.000Z

    a partial feasible solution to the KPCG, i.e., a subset S ? V of items inserted in .... called load in the following, which corresponds to the item weight wi. The goal.

  5. EIGENVALUE ASYMPTOTICS FOR SCHRDINGER OPERATORS ON SPARSE GRAPHS

    E-Print Network [OSTI]

    Recanati, Catherine

    , BKW, D2, DK, F, M1, M2, K1, KL2, Woj1]. In certain more spe- cific geometric situations the bottom

  6. Towards a Better Quality Metric for Graph Cluster Evaluation

    E-Print Network [OSTI]

    Zaki, Mohammed Javeed

    CiÍncia e Tecnologia para a Web - InWeb (MCT/CNPq 573871/2008-6) Copyright c 2012 Permission to copy

  7. Cryptanalysis and improvements on some graph-based authentication schemes

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Salahaddin University, College of Science Mathematics Department, Kurdistan, Iraq email:herish omer69@yahoo

  8. Graph Rotation Systems for Physical Construction of Large Structures

    E-Print Network [OSTI]

    Xing, Qing

    2012-02-14T23:59:59.000Z

    ), Form-Z, Rhinoceros 3D, Cadwork, 3ds Max and SketchUp. However, there are still a lot to do theoretically and practically. 9 II.2. Computer Graphics Applied to Architecture Computer Graphics techniques have been used in mostly virtual design...

  9. On Dissemination Thresholds in Regular and Irregular Graph Classes

    E-Print Network [OSTI]

    Rapaport, I.; Suchan, K.; Todinca, I.; Verstraete, J.

    2011-01-01T23:59:59.000Z

    2003) 13. Hayrapetyan, A. , Kempe, D. , PŠl, M. , Svitkina,Wiley, New York (2000) 16. Kempe, D. , Kleinberg, J. ,

  10. A Brief History of Curves in Graph Drawing David Eppstein

    E-Print Network [OSTI]

    Eppstein, David

    , in the sinuous course of its rivers, in the body of the beloved woman." -- Oscar Niemeyer [2000] Amazon River

  11. Exploring Blog Graphs Patterns and a Model for Information

    E-Print Network [OSTI]

    success, discovering links between companies. Example: blogs in the 2004 election. [Adamic, Glance 2005MichelleMalkin #12;11 Blogosphere network Non-trivial vs. trivial cascades Cascades From networks to cascades slashdot boingboing DlistedMichelleMalkin Time #12;12 From networks to cascades Non-trivial vs. trivial

  12. Space-Variant Computer Vision: A Graph Theoretic Approach

    E-Print Network [OSTI]

    Schwartz, Eric L.

    equation 2 u = 0 Combinatorial Dirichlet integral D[x] = 1 2xT AT CAx Laplace equation AT CAx = Lx = 0 ­ p

  13. Tradespace exploration for space system architectures : a weighted graph framework

    E-Print Network [OSTI]

    Davison, Peter Leslie

    2014-01-01T23:59:59.000Z

    Many systems undergo significant architecture-level change during their lifecycles as a result of exogenous system disturbances (e.g. budget reduction or changes in stakeholder requirements), failure to develop critical ...

  14. Analyzing Network-Wide Interactions Using Graphs: Techniques and Applications

    E-Print Network [OSTI]

    Iliofotou, Marios

    2011-01-01T23:59:59.000Z

    IP networks. They enable network administrators to gain in-Network Managment Network Administrator Figure 1.1: Basica valuable tool for network administrators to detect

  15. Security Optimization of Dynamic Networks with Probabilistic Graph Modeling

    E-Print Network [OSTI]

    Yao, Danfeng "Daphne'

    analysis tools. A network administrator needs to identify vulnerable configurations, as well as tools placement problem, where the network administrator needs to compute on which machine(s) to install new, and services added to or removed from the network. Network administrators also need to respond to newly

  16. On Dependency Graphs and the Lattice Gas Alexander D. Scott

    E-Print Network [OSTI]

    Scott, Alexander Alexander

    College London London WC1E 6BT, England scott@math.ucl.ac.uk Alan D. Sokal Department of Physics New York probability space, for which one wishes to prove that P( xX Ax) > 0, i.e. that with positive probability none for independent subsets of vertices, i.e. the polynomial ZG(w) = X X X independent xX wx , (1.1) where we

  17. Asymptotic Behavior and Distributional Limits of Preferential Attachment Graphs

    E-Print Network [OSTI]

    Chaudhuri, Surajit

    , Christian Borgs, Jennifer T. Chayes and Amin Saberi Mathematics Department, Hebrew University, Jerusalem Alto, CA 94305. e-mail: saberi@stanford August 2009 (revised August 2010) Abstract: We give an explicit;Berger, Borgs, Chayes, Saberi /Preferential attachment limits 2 Earlier, a notion of a weak local limit

  18. Confluence in Data Reduction: Bridging Graph Transformation and Kernelization

    E-Print Network [OSTI]

    Wichmann, Felix

    , Claudia Ermel, Falk H¨uffner , Rolf Niedermeier, and Olga Runge Institut f¨ur Softwaretechnik und Theoretische Informatik, TU Berlin {hartmut.ehrig, claudia.ermel, falk.hueffner, rolf.niedermeier, olga, supported by the AGG software tool. These results support the main goal of our work, namely, to establish

  19. On Superposition of Heterogeneous Edge Processes in Dynamic Random Graphs

    E-Print Network [OSTI]

    Yao, Zhongmei

    between dead/alive (i.e., ON/OFF) states that rep- resent the online/offline behavior of the corresponding

  20. Proximity Graphs for Defining Surfaces over Point Clouds

    E-Print Network [OSTI]

    Behnke, Sven

    over Point Clouds Gabriel Zachmann University of Bonn Germany Jan Klein University of Paderborn Germany

  1. APPROXIMATING SIGNALS SUPPORTED ON GRAPHS Xiaofan Zhu and Michael Rabbat

    E-Print Network [OSTI]

    Rabbat, Michael

    monitoring and the smart grid. For example, in field estimation [1, 2], a large number of wireless sensors these issues. We first generalize the concept of smooth signals and define a metric to measure the smoothness

  2. Semi-Supervised Learning with Graphs Xiaojin Zhu

    E-Print Network [OSTI]

    Zhu, Xiaojin "Jerry"

    Faloutsos, Li Fan, Zhaohui Fan, Marc Fasnacht, Stephen Fienberg, Robert Frederking, Rayid Ghani, Anna, Si Luo, Yong Lu, Matt Mason, Iain Matthews, An- drew McCallum, Uwe Meier, Tom Minka, Tom Mitchell

  3. Consistent cycles in graphs and digraphs Stefko Miklavic

    E-Print Network [OSTI]

    Poto√®nik, Primo¬?

    of this result can be found in Biggs' paper [1]. A sketch of the proof given there is based on a beautiful idea. (see Theorem 4.1.) Many results in this paper follow Biggs [1], but for the sake of self- containedness

  4. Approximating the Minimum Hub Cover Problem on Planar Graphs

    E-Print Network [OSTI]

    2014-11-25T23:59:59.000Z

    Nov 25, 2014 ... The proposed algorithm incrementally constructs a search tree representing the ..... Ph.D. thesis, Sabanci University. Yelbay, B., S. ?I. Birbil,†...

  5. Conic approach to quantum graph parameters using linear ...

    E-Print Network [OSTI]

    2014-07-10T23:59:59.000Z

    Jul 10, 2014 ... that are invariant under action of the permutation group Sym(t) (consisting of all permutations of [t] = {1,...,t}). ...... Private Communications, 2013.

  6. Graph Theory: Problem Set 2 Jan 21, 2013

    E-Print Network [OSTI]

    Harju, Tero

    of G if uNG(v) ((v) - (u)) = 0. Show that G has at least two poles. Solution. Let Amax = {v | (v) is maximum} VG. Since is not a constant function, Amax is a nonempty proper subset of VG. Let A Amax be the set of those vertices v for which there exists a vertex u / Amax such that vu G. Since G is connected

  7. Spectral problems of optical waveguides and quantum graphs

    E-Print Network [OSTI]

    Ong, Beng Seong

    2006-10-30T23:59:59.000Z

    xjj 1g centered at x. We now give a more precise formulation of Theorem 2: Theorem 3. There exist positive constants C1 and C(z) such that k xuk C1 (1 + jx1j)N e C(z)dist(x;Sl); (2.22) where N is the order of polynomial boundedness of u. Remark 4... polynomially 20 one cannot expect anything better. In the periodic situation, using Floquet-Bloch theory, one can guarantee absence of this growth. Details of this claim will be provided at the end of this section. Proof. De ne the sesqui-linear form Q[';w...

  8. Graph spectra and modal dynamics of oscillatory networks

    E-Print Network [OSTI]

    Ayazifar, Babak, 1967-

    2003-01-01T23:59:59.000Z

    Our research focuses on developing design-oriented analytical tools that enable us to better understand how a network comprising dynamic and static elements behaves when it is set in oscillatory motion, and how the ...

  9. Some contributions to graph theory and network analysis

    E-Print Network [OSTI]

    Blumentritt, Charles Wayne

    1964-01-01T23:59:59.000Z

    length of the shortest path of o + 1 or less arcs joining x to x . Again, by de fin ition ik kj k min(ck+ak ) k For k j, (cik + ak ) becomes ci + 0 ci, thus di gives the length of the ik kj ij ij ' ij shortest path, even if that path is composed...

  10. Exploring computer-generated line graphs through virtual touch.

    E-Print Network [OSTI]

    Yu, W.; Ramloll, R.; Brewster, S.A.

    Yu,W. Ramloll,R. Brewster,S.A. Riedel,B. Accepted for publication in IEEE ISSPA 2001 (Kuala-Lumpur, Malaysia), IEEE IEEE

  11. SampleRank: Training Factor Graphs with Atomic Gradients

    E-Print Network [OSTI]

    McCallum, Andrew

    a user-provided loss function to distribute stochastic gradients across an MCMC chain. As a result, parameter updates can be computed between arbitrary MCMC states. Sam- pleRank is not only faster than CD- expensive gradients between the ground-truth and samples along an MCMC chain yielding a stochastic

  12. A Graph Theoretic Mathematical Model for Alzheimer's disease

    E-Print Network [OSTI]

    Baras, John S.

    by microglia, a cytokine that inhibits the secretion of IL1 and TNA. Dysregulation of lipid metabolism lipids that is dysregulated, though its exact mechanism in the AD process is not well

  13. Removing critical nodes from a graph: complexity results and ...

    E-Print Network [OSTI]

    2011-07-29T23:59:59.000Z

    Jul 26, 2011 ... Acknowledgements. This work was mostly carried out while the second author was a postdoctoral fellow in the Dis- crete Optimization group at†...

  14. Large Mesh Deformation Using the Volumetric Graph Laplacian

    E-Print Network [OSTI]

    Kazhdan, Michael

    VGL can impose volume constraints Volumetric constraints are represented by a quadric energy function volume constraints Volumetric constraints are represented by a quadric energy function #12 destination A quadric energy function is generated ≠ Minimum maps the points to their specified destination

  15. Graph Modeling for Quadratic Assignment Problems Associated with ...

    E-Print Network [OSTI]

    2009-02-27T23:59:59.000Z

    Since the the communication system is imperfect, there is a certain probability that the received message is different .... In [21], the authors further lift model (3) to higher dimension, with n6 variables based ...... introduce new artificial variables tl.

  16. Graph Coloring in the Estimation of Sparse Derivative Matrices ...

    E-Print Network [OSTI]

    2004-03-15T23:59:59.000Z

    Mar 15, 2004 ... taining nonzero entries in the column positions mapped by the column segments. A(wėi,q) and A(wėp,j) for all ėp = ėi. This is done for every pair†...

  17. The dimension of semialgebraic subdifferential graphs. 1 Introduction

    E-Print Network [OSTI]

    2011-02-18T23:59:59.000Z

    Feb 18, 2011 ... Consider a semi-algebraic set Q and a finite-to-one, con- tinuous, semi-algebraic map ?: Q ? Rm. Then the map ? does not decrease.

  18. Comparing Two Haptic Interfaces for Multimodal Graph Rendering

    E-Print Network [OSTI]

    Yu, W.; Brewster, S.A.

    Yu,W. Brewster,S.A. 10th Symposium on Haptic Interfaces for Virtual Environment and Teleoperator Systems (Haptics 2002). (Florida USA) pp 3-9 IEEE Computer Society Press

  19. *The graph shown at the top right is the complement of line graph of the complete graph on 8 vertices. The smallest Seidel eigenvalue of this graph is -3 with multiplicity 21. This proves the

    E-Print Network [OSTI]

    in Euclidian space, J. Combin., 7 (2000), Re- search Paper 55, 3 pp. (electronic). [2] J. M. RENES, R. BLUME-KOHOUT

  20. A Graph-Based Toy Model of Chemistry , Christoph Flamm,

    E-Print Network [OSTI]

    Stadler, Peter F.

    substantial sampling biases in the few networks that are known in detail. A computational model for generating of the Frontier Molecular Orbital Theory based on the Extended H¨uckel scheme. The approach is illustrated for two there. Rather, novel molecules can be generated. This is the principal difficulty for any theoretical

  1. Bond graph models of electromechanical systems. The AC generator case

    E-Print Network [OSTI]

    Batlle, Carles

    . After reviewing electromechanical energy conversion and torque gener- ation, the core element present in any electromechanical system is introduced, and the corresponding electrical and mechanical ports are attached to it. No modulated elements are necessary, since the energy representation

  2. Efficient Parallel Graph Algorithms For Coarse Grained Multicomputers and BSP ?

    E-Print Network [OSTI]

    Santoro, Nicola

    7 , and S. W. Song 8 1 Univ. Federal de Mato Grosso do Sul, Campo Grande, Brasil, edson and Engineering Research Council of Canada, FAPESP (Brasil), CNPq (Brasil), PROTEM­2­TCPAC (Brasil

  3. Generating Reports & Graphs in Portfolio Manager | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-UpHeatMulti-Dimensional Subject: Guidance for naturalGeneral Service LED Lamps

  4. Useful Graphs and Charts - Ion Beams - Radiation Effects Facility /

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched Ferromagnetism inS-4500II Field Emission SEMUsed Fuel Disposition ResearchCyclotron

  5. A semidefinite programming based heuristic for graph coloring

    E-Print Network [OSTI]

    compute ?-number in each iteration or recycle the matrix X until there are no remaining .... Preliminary tests show that combining recycling strategy with TABU

  6. A Bond Graphs approach to Physical Modelling of Musical Instruments

    E-Print Network [OSTI]

    McGregor, Andrew

    is the equivalent of the current i flowing in the electric circuit. These equivalencies follow from the fact for representing physical systems, such as an electrical circuit or a mechanical engine. They provide a precise of vibrating media using a network of interconnected mechanical units, called mass and spring. On a computer

  7. DETECTING CRITICAL NODES IN SPARSE GRAPHS Given a ...

    E-Print Network [OSTI]

    2008-08-21T23:59:59.000Z

    the pair-wise disconnectivity among the nodes, but also minimizes the variance in the car- dinalities of the components. Particularly, in Lemma 1 we show that for

  8. Automated Inclusive Design Heuristics Generation with Graph Mining

    E-Print Network [OSTI]

    Sangelkar, Shraddha Chandrakant

    2013-08-01T23:59:59.000Z

    Inclusive design is a concept intended to promote the development of products and environments equally usable by all users, irrespective of their age or ability. This research focuses on developing a method to derive heuristics for inclusive design...

  9. ECCV 2006 tutorial on Graph Cuts vs. Level Sets

    E-Print Network [OSTI]

    Boykov, Yuri

    3 4 1 02 5 ∑ Definition. is a reparameterisation of if they define the same energy: xxx anyfor fractional segmentations ∑ Extend energy: linear programming (LP) relaxation ≠ Now convex problem! Energy,1} xp[0,1] ≠ Allow fractional segmentations ∑ Extend energy: linear programming (LP) relaxation ≠ Now

  10. SIMPLICIAL EMBEDDINGS BETWEEN PANTS GRAPHS Javier Aramayona 1

    E-Print Network [OSTI]

    Aramayona, Javier

    is induced by a surface homeomorphism. More concretely, let be a compact orientable surface whose every, the group of homotopy classes of self-homeomorphisms of . Note that Mod() acts on P() by simplicial]: Theorem 1 ([Mar]). If is a compact, connected, orientable surface with () > 0, then the natural

  11. Global Minimum Cuts in Surface Embedded Graphs Jeff Erickson

    E-Print Network [OSTI]

    Erickson, Jeff

    contract no. DE-AC05-06OR23100. Portions of this work were done while this author was visiting Toyota

  12. Graph theoretic generalizations of clique: optimization and extensions

    E-Print Network [OSTI]

    Balasundaram, Balabhaskar

    2009-05-15T23:59:59.000Z

    and telecommunication industry among others. The focus of this dissertation is a degree-based relaxation called k-plex. A distance-based relaxation called k-clique and a diameter-based relaxation called k-club are also investigated in this dissertation. We present...

  13. Generalized Domination in Graphs with Applications in Wireless Networks

    E-Print Network [OSTI]

    Sung, Je Sang

    2013-12-10T23:59:59.000Z

    failure is considered by studying k-connected m-dominating set. We describe several structural properties that hold form ? k, but fail when m < k. Three different formulations based on vertex-cut inequalities are shown depending on the value of k and m...

  14. Dynamic Graph Generation for Large Scale Operational Train ...

    E-Print Network [OSTI]

    Frank Fischer

    2011-08-01T23:59:59.000Z

    Aug 1, 2011 ... Abstract: The aim of operational train timetabling is to find a conflict free timetable for a set of passenger and freight trains with predefined†...

  15. Sequoia supercomputer tops Graph 500 | National Nuclear Security

    National Nuclear Security Administration (NNSA)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "ofEarlyEnergyDepartmentNational Nuclearhas 'Natitude'SecurityAdministration ranked third in TOP500

  16. Game matching number of graphs Douglas B. West

    E-Print Network [OSTI]

    West, Douglas B.

    . Game: Two players, Max and Min, alternately choose edges of a matching, ending with a maximal matching. Max wants it to be large; Min wants it to be small. #12;The Matching Game We want a large matching but can't pick all the edges. Game: Two players, Max and Min, alternately choose edges of a matching

  17. Graph Coloring in the Estimation of Sparse Derivative Matrices ...

    E-Print Network [OSTI]

    2004-03-15T23:59:59.000Z

    Mar 15, 2004 ... being run for 3 days on a Sun Blade 10 running Solaris. Chaff (a SAT solver) to- .... A sparse matrix library in c++ for high performance†...

  18. Isomorphism testing for circulant graphs Cn(a, b)

    E-Print Network [OSTI]

    2010-03-10T23:59:59.000Z

    Mar 10, 2010 ... Page 1 ... and define a simple combinatorial model, which is new for the topic. Building on such a model, we derive a necessary and sufficient†...

  19. Extremes are better: investigating mental map preservation in dynamic graphs

    E-Print Network [OSTI]

    Purchase, H.C.

    Purchase,H.C. Samra,A. Proceedings of the 5th International Conference on Diagrammatic Representation and Inference pp 60-73

  20. Cuts and Partitions in Graphs/Trees with Applications

    E-Print Network [OSTI]

    Fan, Jia-Hao

    2013-07-23T23:59:59.000Z

    algorithm for the problem, which gives an upper bound of O(k3) on the kernel size, significantly improving the previous best upper bound O(k6). We further exploit this connection to give a parameterized algorithm for the problem that runs in time O? (1.62k...

  1. Notes for Graduate Course "Graphs, Spectral Theory, and

    E-Print Network [OSTI]

    Miller, Stephen David

    of Eisenstein series (some notes on this can be found on my web- page). I wish to thank Jonathan circumventing Weil's deep p __ work showing |K`| 2 p, which is sharp). Our proof is just a geometri- cal rearrangement. There already is a DEEP algebraic- geometric proof

  2. Beyond Streams and Graphs: Dynamic Tensor Analysis Dacheng Tao

    E-Print Network [OSTI]

    not necessarily scale up, let alone operate on semi-infinite streams. Thus, we introduce the dynamic ten- sor nodes; all of them are identical or closely related to eigen analysis or derivatives; 4) social networks- zero entries in the adjacency matrix. The network value of a customer [13] has close ties to the first

  3. Mysteries around the graph Laplacian eigenvalue 4 Yuji Nakatsukasaa

    E-Print Network [OSTI]

    Saito, Naoki

    , which we previously observed through our numerical experiments. The eigen- value distribution, there is a sudden jump. Interest- ingly, the eigenvectors corresponding to the eigenvalues below 4 are semi of any eigen- vector corresponding to the eigenvalue greater than 4 decay exponentially from

  4. Mysteries around the graph Laplacian eigenvalue 4 Yuji Nakatsukasa1

    E-Print Network [OSTI]

    Saito, Naoki

    from the eigen- value 0 up to 4. Then, at the eigenvalue 4, there is a sudden jump as shown in Figure 1 Laplacian eigen- value distributions. (a) 2D projection of dendrites of an RGC of a mouse; (b to the eigenvalues below 4 are semi-global oscillations (like Fourier modes) over the entire tree or one

  5. PUTNAM 2014 WEEK 4: GRAPH THEORY. A graph is a collection of vertices and a collection of edges connecting

    E-Print Network [OSTI]

    Tevelev, Jenia

    to put hats on some people so that people wearing hats are friends with at least as many people not wearing hats as with people wearing hats, and people not wearing hats are friends with at least as many if the corresponding objects are "related". Easier Problems 1. Some people in a room are friends with each other

  6. Introduction to CEAL Online Statistics I

    E-Print Network [OSTI]

    Doll, Vickie; Liu, Wen-ling

    2014-09-25T23:59:59.000Z

    .lib.ku.edu/ceal/php/tblview_adv/tblview_adv.php 1. Search the database and 2. Customize the display fields CEAL stats workshop I 1109/25/2014 Table View (Advance) CEAL stats workshop I 1209/25/2014 Table View (Advance) Step 1: Choose year... in selected year(s) CEAL stats workshop I 2209/25/2014 Graph View Search the database and view the data available as graphs. CEAL stats workshop I 2309/25/2014 Graph View (Advance) CEAL stats workshop I 2409/25/2014 Graph View CEAL stats workshop I 2509...

  7. GRAPHMC

    Energy Science and Technology Software Center (OSTI)

    002928WKSTN00 graphMC: A package for testing the independence of graphs† www.sandia.gov/~apinar/graphMC/graphMC†

  8. A memory-efficient algorithm to obtain splicing graphs and de novo expression estimates from de Bruijn graphs of RNA-Seq data

    E-Print Network [OSTI]

    Sze, Sing-Hoi; Tarone, Aaron M

    2014-07-14T23:59:59.000Z

    tp ro ce ss in g al g or it h m , O as es an d Tr an s- A B yS S us in g si x p ub lic ly av ai la b le lib ra ri es ov er d if fe re n t va lu es of k -m er co ve ra g e cu to ff c . p os tp ro ce ss k _ c in it ia l no de s la rg es t ta ng le la rg... es t SC C sp lic in g gr ap hs m ax le ng th N 50 > 1- no de gr ap hs m ax no de s av g no de s SN Ps to ta l hi ts un iq ue hi ts > 1- hi t gr ap hs m ax hi ts ti m e (m in s) m em or y (G B) 35 _3 22 76 14 17 85 45 88 09 4 75 36 7 10 53 9 54 4 20 48...

  9. Pending Jobs by Group

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Pending Jobs by Group Pending Jobs by Group Daily Graph: Weekly Graph: Monthly Graph: Yearly Graph: 2 Year Graph: Last edited: 2011-04-05 14:00:14...

  10. Long Term by Group

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Running Jobs by Group Running Jobs by Group Daily Graph: Weekly Graph: Monthly Graph: Yearly Graph: 2 Year Graph: Last edited: 2011-04-05 13:59:48...

  11. Expanded Pending Jobs by Group

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Expanded Pending Jobs by Group Expanded Pending Jobs by Group Daily Graph: Weekly Graph: Monthly Graph: Yearly Graph: 2 Year Graph: Last edited: 2011-04-05 14:00:25...

  12. Private Social Network Analysis: How to Assemble Pieces of a Graph Privately

    E-Print Network [OSTI]

    Golle, Philippe

    University 230 Kreger Hall Oxford, OH 45056 frikkekb@muohio.edu Philippe Golle Palo Alto Research Center 3333 Coyote Hill Rd Palo Alto, CA, 94304 pgolle@parc.com ABSTRACT Connections in distributed systems ACM 1-58113-968-3/06/0010 ...$5.00. population of users with connections defined, for example, by who

  13. The Abstract Task Graph: A Methodology for Architecture-Independent Programming of Networked Sensor Systems

    E-Print Network [OSTI]

    Prasanna, Viktor K.

    Center 3333 Coyote Hill Road Palo Alto, CA 94304 USA jreich, larner @parc.com Abstract The Abstract Task-provided code that implements the actual information processing functions in the sys- tem. Appropriate numbers and network configuration, with each node incorporating the user-provided code, automatically gen- erated glue

  14. SAFE COOPERATIVE ROBOT DYNAMICS ON GRAPHS ROBERT W. GHRIST AND DANIEL E. KODITSCHEK

    E-Print Network [OSTI]

    Ghrist, Robert W.

    . This paper initiates the use of vector fields to design, optimize, and implement reactive sched- ules. Introduction. Recent literature suggests the growing awareness of a need for "reactive" scheduling wherein one the original domain. This paper explores the use of vector fields for reactive scheduling of safe cooper- ative

  15. Lower and upper queries for graph-mining Amina Kemmar 1

    E-Print Network [OSTI]

    Boyer, Edmond

    , and Mohammed Ouali 1 1 Laboratoire LITIO, Universit¬īe d'Oran BP 1524, El-M'Naouer, 31000 Oran, Alg¬īerie 2

  16. Challenges in large-scale graph processing on HPC platforms and the

    E-Print Network [OSTI]

    Yuan, Xin

    Dockery #12;High Performance Computing Workloads Core-memory sized Floating point intensive Well-structured def high performance computing zone in on parallel/distributed nature and the amount of communication describe conventional workload High performance computing typically refers to the connection of a large

  17. Micro-grid State Estimation Using Belief Propagation on Factor Graphs

    E-Print Network [OSTI]

    Kavcic, Aleksandar

    to environmental and energy sustainability concerns, variable pricing, sophisticated communication and sensing energy resources and enable a future self-dispatch and self- healing grid. This would first require, renewable energy generation become more prevalent (with intermittent sources such as wind and solar) due

  18. Consistent Weighted Graph Layouts Dana Vrajitoru and Jason DeBoni

    E-Print Network [OSTI]

    Vrajitoru, Dana

    of years from now some aliens discover traces of human civilization on Earth and they try to recover our, and that all that the aliens find is a schedule of an airline company containing the amount of time that each flight would require to connect a given city to another. The problem is, can the aliens reconstruct

  19. Exploring the use of Reeb graphs in LOD generation Benoit LANGE

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    rue Ada 34392 Montpellier Cedex 5 - France Benoit.lange@lirmm.fr Nancy RODRIGUEZ LIRMM LIRMM, UMR 5506 - CC 477 161 rue Ada 34392 Montpellier Cedex 5 - France Nancy.Rodriguez@lirmm.fr ABSTRACT Level model. In 1976, James Clark introduces the LOD concept [1]. It was use for produce different resolution

  20. Cut Graph Based Information Storage and Retrieval in 3D Sensor Networks with General Topology

    E-Print Network [OSTI]

    Wu, Hongyi

    curve with the guaranteed success to retrieve aggregated data through time and space with one and a balanced traffic load. I. INTRODUCTION This research focuses on in-network data-centric informa- tion along a curve called replication curve, and a query travels along another curve called retrieval curve