Computer Science Journal (AGH University of Science and Technology, Krakow)
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Desynchronization of simulation and optimization algorithms in HPC Environment
Get PDFNeed for scalability of an algorithm is essential, when one wants to utilize HPC infrastructure in an efficient and reasonable way. In such infrastructures, synchronization affects the efficiency of the parallel algorithms. However, one can consider introducing certain means of desynchronization in order to increase scalability. Allowing for omitting or delaying certain messages, can be easily accepted in the case of metaheuristics. Furthermore, some simulations can also follow this pattern and handle bigger environments. The paper presents a short survey of desynchronization idea, pointing out already obtained results or sketching out the future work focused on scaling the parallel and distributed computing or simulation algorithms leveraging desynchronization
A multi--criterion simulation model to determine dengue outbreaks
No full textIn this study we develop a multi-criteria model to identify dengue outbreak periods. To validate the model, we perform simulation using dengue transmission related data in the Western Province, Sri Lanka. Our results indicate that the developed model can be used to predict the dengue outbreak situation in a given region upto one month
Data Censoring with Set-Membership Affine Projection Algorithm
Get PDFIn this paper, the set-membership affine projection (SM-AP) algorithm is utilized to censor non-informative data in big data applications. To this end, the probability distribution of the additive noise signal and the excess of the mean-squared error (EMSE) in steady-state are employed in order to estimate the threshold parameter of the single threshold SM-AP (ST-SM-AP) algorithm aiming at attaining the desired update rate. Furthermore, by defining an acceptable range for the error signal, the double threshold SM-AP (DT-SM-AP) algorithm is proposed to detect very large errors due to the irrelevant data such as outliers. The DT-SM-AP algorithm can censor non-informative and irrelevant data in big data applications, and it can improve the misalignment and convergence rate of the learning process with high computational efficiency. The simulation and numerical results corroborate the superiority of the proposed algorithms over traditional algorithms
A CELLULAR AUTOMATA MODELS OF EVOLUTION OF TRANSPORTATION NETWORKS
Get PDFWe present a new approach to modelling o f transportation networks. Supply o f resources and their influence on the evolution o f the consuming environment is a principal problem considered. We present two concepts, which are based on cellular automata paradigm. In thefirst model SCAMAN {Simple CellularAutomata Model ofAnastomosing NetWork), the system is represented by a 2D mesh o f elementary cells. The rules o f interaction between them are introducedfor modelling of the waterflow and other phenomena connected with anastomosing river. Due to limitations o f SCAMAN model, we introduce a supplementary model. The MANGraCA {Model o fAnastomosing NetWork with Graph o f Cellular Automa ta) model beside the classical mesh o f automata, introduces an additional structure: the graph o f cellular automata, which represents the network pattern. Finally we discuss the prospective applications of the models. The concepts offuturę implementation are also presented
RESOLYING AMBIGUITIES OF MEANING FROM CONTEXTUAL CLUES IN POLISH TEXTS
Get PDFThis article describes a Computer programme designed to assign the appropriate meaning to homonyms based on the context in which they appear. Homonyms can be defined as words with a number o f dijferent, often unrelated, meanings (for example a bank - a business that lends or keeps money, the land along the side o f river, a large pile o f earth, sand, snów).The programme described in the paper exploits a monolingual dictionary, which, together with and supported by declension dictionary assigns the appropriate meaningfor any given wordfrom the text. In order to assign the correct and appropriate meaningfor the given context two methods are used and exploited:1) Recognition o f the meaning o f a particular homonym based on the occurrence o f its collocations in the immediate context.2) Applying the correct meaning o f the word based on the overall theme or topie o f the text in which appears
AUTOMATIC EXTRACTION OF SEMANTIC ASSOCIATION FROM POLISH TEXT
Get PDFIn the paper we presents a methodfor automatic construction of an association listfor a particular word. Association list is a set o f word, each o f which is in a semantic relation with the words.to dejine. To construct the association list we use statistic reasoning algory- thm, which works on the base o f the Polish inflection dictionary, text corpus, and the quan- titative dictionary createdfor the corpus. Experiments are encouraging enough - one may think that the association can serve as the basefor the entry in a semantic dictionary
FINITE-STATE METHODOLOGY IN NATURAL LANGUAGE PROCESSING
Get PDFRcccnt mathcmatical and algorithmic rcsults in thc field of fmite-state tcchnology, as well as thc increasc in computing powcr, havc constructcd thc basc for a ncw approach in natural languagc Processing.Howcvcr the task of creating an appropriatc model that would dcscribe thc phcnomcna of thc natural languagc is still to be achicvcd. In this papcr l’m prcscnting somc notions rclated to thc finitc-statc modclling of syntax and morphology
Extracting class diagram from hidden dependencies in data set
Get PDFA conceptual model is a high-level, graphical representation of a specic do-main, presenting its key concepts and relationships between them. In particular, these dependencies can be inferred from concepts\u27 instances being a part of big raw data les. The paper aims to propose a method for constructing a conceptual model from data frames encompassed in data les. The result is presented in the form of a class diagram. The method is explained with several examples and veried by a case study in which the real data sets are processed. It can also be applied for checking the quality of the data set
An efficient implementation of the Chinese Remainder Theorem in minimally redundant Residue Number System
No full textThe Chinese Remainder Theorem (CRT) widely used in many modern computer applications. This paper presents an efficient approach to the calculation of the rank of a number, a principal positional characteristic used in the Residue Number System (RNS). The proposed method does not use large modulo addition operations compared to a straightforward implementation of the CRT algorithm. The rank of a number is equal to a sum of an inexact rank and a two-valued correction factor that only takes on the values 0 or 1. We propose a minimally redundant RNS, which provides low computational complexity of the rank calculation. The effectiveness of the novel method is analyzed concerning conventional non-redundant RNS. Owing to the extension of the residue code, by adding the extra residue modulo 2, the complexity of rank calculation goes down from to , where equals the number of residues in non-redundant RNS
SEMIGROUPS, GROUPS AND GRAMMARINFERENCE PROBLEM
Get PDFIn the paper we analyse a problem o f inferring a grammarfrom a given sample o f a langu- age. We try topresent an algebraicformalism capable ofdescribing the issue. We consider two cases: a case o f inferring canonical finite-state grammars, and a case o f inferring generał grammars. In both cases we define a semigroup structure. Finally we look at the possibility o f getting a structure o f a group