Search results for "Algorithms"
showing 10 items of 1716 documents
Modelling complex dynamics and distributed generation of knowledge with bacterial-based algorithms
2014
Este estudio tuvo como objetivo demostrar que las sociedades conectadas y heterogéneas con intercambios entre pares (P2P) son más resilientes que las centralizadas y homogéneas. En el modelado basado en agentes, se modelizan agentes con racionalidad limitada que interactúan en un entorno común guiado por reglas locales, lo que lleva a Sistemas Adaptativos Complejos (CAS) que se denominan 'sociedades artificiales'. Estos modelos simplificados de sociedades humanas crecen de abajo hacia arriba en entornos computacionales y pueden utilizarse como un laboratorio para probar algunas hipótesis. Hemos demostrado que en un modelo basado en interacciones libres entre agentes autónomos, los resultado…
Fast and Simple Approximation of the Diameter and Radius of a Graph
2006
The increasing amount of data to be processed by computers has led to the need for highly efficient algorithms for various computational problems. Moreover, the algorithms should be as simple as possible to be practically applicable. In this paper we propose a very simple approximation algorithm for finding the diameter and the radius of an undirected graph. The algorithm runs in $O(m\sqrt{n})$ time and gives an additive error of $O(\sqrt{n})$ for a graph with n vertices and m edges. Practical experiments show that the results of our algorithm are close to the optimum and compare favorably to the 2/3-approximation algorithm for the diameter problem by Aingworth et al [1].
Comparative genomics and protein domain graph analyses link ubiquitination and RNA metabolism.
2006
The human gene parkin, known to cause familial Parkinson disease, as well as several other genes, likely involved in other neurodegenerative diseases or in cancer, encode proteins of the RBR family of ubiquitin ligases. Here, we describe the structural diversity of the RBR family in order to infer their functional roles. Of particular interest is a relationship detected between RBR-mediated ubiquitination and RNA metabolism: a few RBR proteins contain RNA binding domains and DEAH-box RNA helicase domains. Global protein domain graph analyses demonstrate that this connection is not RBR-specific, but instead many other proteins contain both ubiquitination and RNA-related domains. These protei…
Identifying individuality and variability in team tactics by means of statistical shape analysis and multilayer perceptrons.
2012
Abstract Offensive and defensive systems of play represent important aspects of team sports. They include the players’ positions at certain situations during a match, i.e., when players have to be on specific positions on the court. Patterns of play emerge based on the formations of the players on the court. Recognition of these patterns is important to react adequately and to adjust own strategies to the opponent. Furthermore, the ability to apply variable patterns of play seems to be promising since they make it harder for the opponent to adjust. The purpose of this study is to identify different team tactical patterns in volleyball and to analyze differences in variability. Overall 120 s…
Linear-size suffix tries
2016
Suffix trees are highly regarded data structures for text indexing and string algorithms [MCreight 76, Weiner 73]. For any given string w of length n = | w | , a suffix tree for w takes O ( n ) nodes and links. It is often presented as a compacted version of a suffix trie for w, where the latter is the trie (or digital search tree) built on the suffixes of w. Here the compaction process replaces each maximal chain of unary nodes with a single arc. For this, the suffix tree requires that the labels of its arcs are substrings encoded as pointers to w (or equivalent information). On the contrary, the arcs of the suffix trie are labeled by single symbols but there can be Θ ( n 2 ) nodes and lin…
Table Compression
2016
Data Compression Techniques for massive tables are described. Related methodological results are also presented.
Fully Automatic Trunk Packing with Free Placements
2010
We present a new algorithm to compute the volume of a trunk according to the SAE J1100 standard. Our new algorithm uses state-of-the-art methods from computational geometry and from combinatorial optimization. It finds better solutions than previous approaches for small trunks.
Continuous reformulations and heuristics for the Euclidean travelling salesperson problem
2008
We consider continuous reformulations of the Euclidean travelling salesperson problem (TSP), based on certain clustering problem formulations. These reformulations allow us to apply a generalisation with perturbations of the Weiszfeld algorithm in an attempt to find local approximate solutions to the Euclidean TSP.
An Analysis of the Influence of Noneffective Instructions in Linear Genetic Programming
2020
Abstract Linear Genetic Programming (LGP) represents programs as sequences of instructions and has a Directed Acyclic Graph (DAG) dataflow. The results of instructions are stored in registers that can be used as arguments by other instructions. Instructions that are disconnected from the main part of the program are called noneffective instructions, or structural introns. They also appear in other DAG-based GP approaches like Cartesian Genetic Programming (CGP). This article studies four hypotheses on the role of structural introns: noneffective instructions (1) serve as evolutionary memory, where evolved information is stored and later used in search, (2) preserve population diversity, (3)…
Fermion sign problem in imaginary-time projection continuum quantum Monte Carlo with local interaction
2016
We use the Shadow Wave Function formalism as a convenient model to study the fermion sign problem affecting all projector Quantum Monte Carlo methods in continuum space. We demonstrate that the efficiency of imaginary time projection algorithms decays exponentially with increasing number of particles and/or imaginary-time propagation. Moreover, we derive an analytical expression that connects the localization of the system with the magnitude of the sign problem, illustrating this prediction through some numerical results. Finally, we discuss the fermion sign problem computational complexity and methods for alleviating its severity.