No. 5/2017

Online archive of Computer Science and Mathematical Modelling

No. 5/2017

  1. P. Augustynowicz, A. Buraczyńska - Comparison between experimental, analytical and simulation model of distributed computation on ARM processors in High-Performance Computing
    Pages: 5 - 10
    Abstract: The paper presents a comparison between experimental, analytical and simulation model of distributed cryptographic computation regarding password recovery with SHA 1 password hashing. The aim of this paper is compare popular mobile ARM processors with their Intel Atom analogue and determine their usefulness in cryptographic computations from High Performance Computing (HPC) point of view. During the construction process of HPC cluster, three different versions of Raspberry Pi computers were used. Then the constructed model was applied to develop an analytical and simulation models that allow calculating most influential characteristics from HPC clusters administrator’s point of view. Reference model was constructed on Intel Atom processors.
    Keywords ARM processors, High-Performance Computing, Analytical Model
    Full article: PDF icon 5_10_csmm_5_paugustynowicz.pdf
  2. K. Banach, R. Kasprzyk - Software environment for rapid prototyping of graph and network algorithms
    Pages: 11 - 16
    Abstract: The article presents an innovative software environment for rapid prototyping of graph and network algorithms. The environment consists of two main components: an editor of graphs & networks and an editor of algorithms’ code. The presented environment enables interactive visualization of algorithms implemented therein, which in turn allows quick verification of algorithms results as well as its correctness. The aim of the environment construction was to provide a solution for rapid prototyping of novel algorithms. The developed tool can also be successfully used for educational purposes.
    Keywords graph and network theory, algorithms prototyping, algorithms visualization
    Full article: PDF icon 11_16_csmm_5_kbanach_rkasprzyk.pdf
  3. D. Dzida - Using complex networks in social impact models
    Pages: 17 - 28
    Abstract: This paper describes models of opinion dynamics. It presents various ways of modelling opinion spreading in the population. The author proposes to apply complex networks to a model, which is based on the theory of social impact. The agent based modelling is applied to construct the model and perform simulations. Performed simulations allowed to investigate how the use of complex networks and its properties have an influence on the final distribution of opinions in the population. The results of simulations have been shown and interpreted.
    Keywords social impact model, social simulation, opinion dynamics, complex networks
    Full article: PDF icon 17_28_csmm_5_ddzida.pdf
  4. P.A. Ryszawa - On sentence membership problem in context sensitive languages
    Pages: 29 - 44
    Abstract: A new type of graph is introduced, the grammar graph. The possibility of assigning labels to each node in such a graph extends it to the grammar net. The grammar net should be considered as a new graphical tool that helps in an analysis of whether a particular sentence belongs to a given context-sensitive grammar. Another concept, the derivation net, closely related to the grammar graph and of a similar structure, will be used to show an algorithm that is able to decide that some sentences do not belong to a language generated by a context sensitive grammar, while leaving others as a candidate members of it.
    Keywords context-sensitive grammar, non-contracting grammar, formal language, graph, parsing
    Full article: PDF icon 29_44_csmm_5_pryszawa.pdf
  5. P. Wołoszyn - Assessment of ranking algorithms in complex networks
    Pages: 45 - 51
    Abstract: A particularly helpful search of a network such as the Internet or a citation network not only finds nodes that satisfy some criteria but also ranks those nodes for importance to create what amounts to a “reading list”. In the recent past, there has been a large interest across a number of research communities in the analysis of complex networks. The selected set of pages from the World Wide Web can be modeled as a directed graph, where nodes are designated as individual pages, and the links as a connection between them. As the number of webpages to be ranked is in the billions, the computation is time-consuming and can take several days or more. Algorithms like PageRank, HITS, SALSA and their modifications has a challenge to deal with the size of the processed data. The need for accelerated algorithms is clear. This article presents the characteristics of three best known ranking algorithms and the assumptions for new algorithm development with first test runs.
    Keywords link analysis, web search, HITS algorithm, Kleinberg’s HITS algorithm, PageRank algorithm, SALSA algorithm, hubs, authorities.
    Full article: PDF icon 45_51_csmm_5_pwoloszyn.pdf