LATIN 2008 - Theoretical Informatics 8th Latin American Symposium, Búzios, Brazil, April 7-11, 2008, Proceedings

• Main Authors: Laber, Eduardo Sany, Bornstein, Claudson, Nogueira, Loana Tito, Faria, Luerbio
• Format: eBook
• Language: English
• Published: Berlin, Heidelberg Springer Berlin / Heidelberg 2008; Springer
• Edition: 1
• Series: Lecture Notes in Computer Science
• ISBN: 9783540787723; 3540787720

This proceedings volume examines a range of topics in theoretical computer science, including automata theory, data compression, logic, machine learning, mathematical programming, parallel and distributed computing, quantum computing and random structures.

Table of Contents:

• Intro -- Title Page -- Preface -- Organization -- Table of Contents -- Profile of Tries -- Introduction -- Summary of Main Results -- Random 2-XORSAT at the Satisfiability Threshold -- Introduction -- Context -- Main Result and Outline of Proof -- Organization of the Paper and Further Results as || is Large -- Exact Enumeration -- Generating Functions -- Differential Recurrence for EGFs -- Inequalities for EGFs -- Proof of Theorem 1 -- Proof of Fact (i) -- Sketch of the Proof of Fact (ii) -- Conclusion -- On Dissemination Thresholds in Regular and Irregular Graph Classes -- Introduction -- Regular Graphs -- Cubic Graphs -- Random Cubic Graphs -- p_c({\cal G}_3) \geq \frac{1}{2} -- Wheels and Toroidal Grids -- How to Complete a Doubling Metric -- Introduction -- Our Results -- Related Work -- Preliminaries and Notation -- A Structure Theorem -- Convex Completions for Graphs -- The Spanner Construction -- Bounding the Dimension of the Convex Closure -- Convex Completions for Trees -- The Construction for Trees -- Bounding the Dimension of the Convex Closure: The Tree Case -- Sorting and Selection with Random Costs -- Introduction -- A Motivation from Game Theory -- Our Results -- Preliminaries -- Uniform Comparison Costs -- Boolean Comparison Costs -- Unit and Infinite Comparison Costs -- Conclusions and Open Questions -- Guided Search and a Faster DeterministicAlgorithm for 3-SAT -- Introduction -- The Local Search Algorithm k-SAT -- Branching Rules -- Simple Branching Rules -- Partial Exact Assignments and Guided Search -- Conclusions -- Comparing and Aggregating Partially Resolved Trees -- Introduction -- Preliminaries -- Distance Measures for Phylogenies -- Properties of Parametric Distance -- Relationships Among the Metrics -- Computing Parametric Distance -- Computing the Parametric Triplet Distance
• The Integrality of the LCS Polytope -- Formulation for the RFLCS -- The Separation Problem for the Extended Star Inequalities -- Computational Results -- Conclusion -- Competitive Cost Sharing withEconomies of Scale -- Introduction -- Model and Basic Properties -- Covering and Facility Location -- Cost and Complexity of Nash Equilibria -- Approximate Nash Equilibria -- Single Element Players -- Emergency Connectivity in Ad-Hoc Networkswith Selfish Nodes -- Introduction -- Model and Terminology -- Characterization of Nash Equilibria -- Connected Equilibria -- NP-hardness of Existence of a Connected Nash Equilibrium -- Conclusion -- Fully-Compressed Suffix Trees -- Introduction and Related Work -- Basic Concepts -- Using Compressed Suffix Arrays -- The Sampled Suffix Tree -- Computing LSA for Leaves -- The Kernel Operations -- Two Fundamental Observations -- Entangled Operations -- Breaking the Cycle -- Further Operations -- Conclusions and Future Work -- Improved Dynamic Rank-Select Entropy-BoundStructures -- Introduction and Related Work -- Collection of Searchable Partial Sums with Indels -- Uncompressed Dynamic Rank-Select Structures for a Small Alphabet -- Compressed Dynamic Rank-Select Structures -- Conclusions -- An Improved Algorithm Finding NearestNeighbor Using Kd-trees -- Introduction -- Preliminaries -- Problem Statement -- Kd-trees -- An Improved Search Algorithm on Kd-trees -- Traditional Kd-tree Algorithms Fails with High Probability -- Modified Algorithm has a Higher Probability of Success -- Experiments -- List Update with Locality of Reference -- Introduction -- Bijective Analysis -- List Update with Locality of Reference -- Experimental Results and Analysis -- Conclusions -- Approximating Steiner Networks with NodeWeights -- Introduction -- Motivation, Problem Definition, and Previous Work -- Our Results
• Decomposition of Covers of Uncrossable Families
• Randomization -- Maximizing the Minimum Load for SelfishAgents -- Introduction -- Unsuccessful Directions -- PTAS for Constant m -- FPTAS for Constant m -- An FPTAS Which is Not Monotone -- Approximation Algorithm SNC for Arbitrary Values of m -- Algorithms for Small Numbers of Machines -- Approximate Polynomial gcd:Small Degree and Small Height Perturbations -- Introduction -- Gcd of Large Degree -- Gcd of Large Height -- Pseudorandom Graphs from Elliptic Curves -- Introduction -- Motivation -- Our Results -- Outline of the Paper and Notation -- Preparation -- Background on Elliptic Curves -- Exponential Sums -- Main Results -- Construction -- Estimates -- Remarks -- Speeding-Up Lattice Reduction with RandomProjections -- Introduction -- Some Reminders on Lattices -- Probabilistic Reduction of Rectangular Lattices -- High-Level Description of the Algorithm -- Complexity Analysis -- Probabilistic Correctness in Two Continuous Models -- Probabilistic Correctness in the Gaussian Model -- Probabilistic Correctness in the Unit Ball Model -- Experimental Data -- Sparse Approximate Solutions to SemidefinitePrograms -- Introduction -- Existence of Sparse Solutions -- Preliminaries -- A Sparse Approximate SDP Solver -- Using Approximate Eigenvector Computations -- Solving General SDPs -- QST in Linear Time -- On the Facets of Mixed Integer Programswith Two Integer Variables and Two Constraints -- Introduction -- Facets of Rf and Facets of Rf(r1, ƒ, rk) -- Split Inequalities -- Nondegenerate Case -- Degenerate Case -- Triangle and Quadrilateral Inequalities -- Triangle Inequalities -- Quadrilateral Inequalities -- Degenerate Triangle and Quadrilateral Inequalities -- A Polyhedral Investigation of the LCS Problemand a Repetition-Free Variant -- Introduction -- A Polyhedral Study of the LCS Polytope -- The Separation Problem for the Star Inequalities
• An Approximation Algorithm for Parametric Quartet Distance -- Computing the Growth of the Number ofOverlap-Free Words with Spectra of Matrices -- Introduction -- The Minimal and Maximal Rates of Growth of the Overlap-Free Words -- The Average Rate of Growth: The Lyapunov Exponent -- Conclusions -- On Stateless Multihead Automata:Hierarchies and the Emptiness Problem -- Introduction -- Stateless Multihead Two-Way Automata -- Stateless Multihead One-way Automata -- The Emptiness Problem -- Myhill-Nerode Theorem forRecognizable Tree Series Revisited -- Introduction -- Preliminaries -- Recognizable Yields Finite Index -- Finite Index Yields Recognizable -- Minimization of Deterministic All-Accepting wta -- A Myhill-Nerode Congruence for Cancellative Semirings -- A Myhill-Nerode Theorem for All-Accepting wta -- The View Selection Problemfor Regular Path Queries -- Introduction -- Regular Path Query Rewritings -- Viewsets of Minimal Cardinality and p-Containment -- Maximal Factors of Regular Languages -- Algorithm -- Arbitrary Rewritings and p-Containment of Viewsets -- Viewsets of Minimal Size -- Conclusion -- Optimal Higher Order Delaunay Triangulations of Polygons -- Introduction -- Higher Order Delaunay Triangulations -- Triangulating Polygons -- Triangulating Polygons with Points Inside -- Some Other Measures -- Application to Point Sets -- Discussion -- Coloring Geometric Range Spaces -- Introduction -- Halfplanes -- Lower Halfspaces in R3 -- Disks and Pseudo-disks -- Local Algorithms for Dominating and ConnectedDominating Sets of Unit Disk Graphs withLocation Aware Nodes -- Introduction -- Related Work -- Preliminaries and Results of the Paper -- Local Algorithm for Dominating Set of a UDG -- Construction of the Dominating Set -- Local Algorithm for Connected Dominating Set of a UDG -- Conclusion -- Spanners of Complete k-PartiteGeometric Graphs
• Introduction -- The Well-Separated Pair Decomposition -- A First Algorithm -- Analysis of Algorithm 1 -- An Improved Algorithm -- Improving the Stretch Factor -- Minimum Cost Homomorphisms to ReflexiveDigraphs -- Introduction and Terminology -- Structure and Forbidden Subgraphs -- Complexity -- On the Complexity of Reconstructing H-freeGraphs from Their Star Systems -- Introduction -- Preliminaries -- Forbidding Short Paths and Cycles -- Forbidding Short Paths -- Forbidding C3 and C4 -- Forbidding Long Paths and Cycles -- Closing Remarks -- Optimization and Recognition for K5-minor FreeGraphs in Linear Time -- Results and Related Work -- The Structure of K5-minor Free Graphs -- Cutset Structure -- Cutset Structure Relative to a Reduction -- The Algorithm -- Running Time -- Applications -- Finding a Separator -- k-Realizations -- Further Applications -- More Details -- Bandwidth of Bipartite Permutation Graphs inPolynomial Time -- Introduction -- Preliminaries -- Bandwidth of Bipartite Permutation Graphs -- Deciding the Existence of Desired Layouts -- A Polynomial-Time Algorithm for Computing the Bandwidth of Bipartite Permutation Graphs -- The Online Transportation Problem: On theExponential Boost of One Extra Server -- Introduction -- Previous Results -- Our Results -- Online Transportation on a Star -- The General Lower Bound -- BODS on the Star -- Generalization to HSTs -- Generalization to Any Metric Space -- Conclusions -- Average Rate Speed Scaling -- Introduction -- Other Related Results -- Formal Problem Statement -- The Lower Bound -- An Elementary Proof that AVR is 2-1-competitive -- Conclusion -- Geometric Aspects of Online Packet Buffering:An Optimal Randomized Algorithm for TwoBuffers -- Introduction -- Preliminaries -- Algorithm PBF -- Outline of the Proof -- Worst-Case Sequences -- Performance Ratio on Regular Sequences