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Wyniki wyszukiwania dla: RAMSEY NUMBER

Wyniki wyszukiwania dla: RAMSEY NUMBER

  • Brushing with additional cleaning restrictions

    Publikacja

    In graph cleaning problems, brushes clean a graph by traversing it subject to certain rules. We consider the process where at each time step, a vertex that has at least as many brushes as incident, contaminated edges, sends brushes down these edges to clean them. Various problems arise, such as determining the minimum number of brushes (called the brush number) that are required to clean the entire graph. Here, we study a new variant...

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  • Drawing maps with advice

    Publikacja

    W pracy podejmujemy temat konstrukcji algorytmu dla agenta, który zostaje umieszczony w dowolnym wierzchołku grafu (wierzchołki są nierozróżnialne, krawędzie mają etykiety portów), po czym realizuje algorytm zmierzający do znalezienia drzewa spinającego grafu lub izomorficznej kopii grafu. Dla obu problemów podajemy asymptotycznie dokładne lub prawie dokładne oszacowania na ilość bitów dodatkowej informacji, którą agent musi otrzymać...

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  • Protokół transmisji sensorowej sieci Ad Hoc

    W referacie zaprezentowano protokół radiowej sieci sensorowej Ad Hoc. Sieć ta pracuje w oparciu o metodę wielodostępu TDMA. Szybkość transmisji w kanale radiowym wynosi 57,6 kb/s. W referacie przedstawiono budowę ramek, rodzaje pakietów oraz procedury przypisania wolnych szczelin czasowych do węzła, zwalniania przypisanych szczelin i wykrywania konfliktów przyporządkowania szczelin.

  • Erratum to "Formulas and Theorems for the Special Functions of Mathematical Physics" by W. Magnus, F. Oberhettinger, R. P. Soni

    Publikacja

    We correct a number of misprints in the handbook "Formulas and theorems for the special functions of mathematial physics" (3rd edition) by Magnus, Oberhettinger and Soni.

  • Strategic balance in graphs

    For a given graph G, a nonempty subset S contained in V ( G ) is an alliance iff for each vertex v ∈ S there are at least as many vertices from the closed neighbourhood of v in S as in V ( G ) − S. An alliance is global if it is also a dominating set of G. The alliance partition number of G was defined in Hedetniemi et al. (2004) to be the maximum number of sets in a partition of V ( G ) such that each set is an alliance. Similarly,...

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  • Seagrass vegetation and meiofauna enhance the bacterial abundance in the Baltic Sea sediments (Puck Bay)

    Publikacja

    - ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH - Rok 2015

    This study presents the first report on bacterial communities in the sediments of eelgrass (Zostera marina) meadows in the shallow southern Baltic Sea (Puck Bay). Total bacterial cell numbers (TBNs) and bacteria biomass (BBM) assessed with the use of epifluorescence microscope and Norland’s formula were compared between bare and vegetated sediments at two localities and in two sampling summer months. Significantly higher TBNs and...

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  • Mathematical modeling and prediction of pit to crack transition under cyclic thermal load using artificial neural network

    Publikacja

    - Rok 2023

    The formation of pitting is a major problem in most metals, which is caused by extremely localized corrosion that creates small holes in metal and subsequently, it changes into cracks under mechanical load, thermo-mechanical stress, and corrosion process factors. This research aims to study pit to crack transition phenomenon of steel boiler heat tubes under cyclic thermal load, and mathematical modeling...

  • Total Completion Time Minimization for Scheduling with Incompatibility Cliques

    Publikacja

    - Rok 2021

    This paper considers parallel machine scheduling with incompatibilities between jobs. The jobs form a graph equivalent to a collection of disjoint cliques. No two jobs in a clique are allowed to be assigned to the same machine. Scheduling with incompatibilities between jobs represents a well-established line of research in scheduling theory and the case of disjoint cliques has received increasing attention in recent...

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  • Iwona Gabriel dr hab. inż.

  • Structure and properties of liquid Al–Cu alloys: Empirical potentials compared

    We report on the structure and mass transport properties of liquid Al–Cu alloys predicted by two recently-developed empirical many-body potentials: MEAM (Jelinek et al., 2012) and EAM-ADP (Apostol and Mishin, 2011), and by the well-known Gupta potential. Total and partial pair correlation functions, angular distribution functions, densities, coordination numbers and self-diffusion coefficients are compared with published experimental...

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  • Modeling of Passive and Forced Convection Heat Transfer in Channels with Rib Turbulators

    Publikacja

    - ENERGIES - Rok 2021

    The main goal of the research presented in this paper was the experimental and numerical analysis of heat enhancement and aerodynamic phenomena during air flow in a channel equipped with flow turbulators in the form of properly configured ribs. The use of ribs intensifies the heat transfer and at the same time increases not only the flow resistance but also the energy costs. Therefore, designing modern heat exchangers with optimal...

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  • Iwona Nowakowska dr

    Osoby

    Adiunkt badawczo-dydaktyczny w Instytucie Psychologii Akademii Pedagogiki Specjalnej im. Marii Grzegorzewskiej w Warszawie. Absolwentka psychologii (Uniwersytet Warszawski, 2019), doktor nauk społecznych w dyscyplinie psychologia (Akademia Pedagogiki Specjalnej im. Marii Grzegorzewskiej, 2022). Prowadziła badania w obszarach: pogranicza psychologii społecznej i klinicznej oraz społecznej i różnic indywidualnych. Obecna aktywność...

  • Depth Determination Accuracy of the Modified Prony Method in a Swath Mapping Application

    Publikacja

    - Rok 2018

    This article presents the performance of the modified Prony method in a swath mapping application. Depth determination accuracy is assessed by processing raw signal acquired by an EdgeTech 6205 swath bathymetry system over flat seafloor. An updated version of the method, proposed previously by the authors, is used to determine the number of signal echoes. The number of signal echoes is essential for performing the low-rank approximation...

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  • The Use of an Autoencoder in the Problem of Shepherding

    Publikacja

    This paper refers to the problem of shepherding clusters of passive agents consisting of a large number of objects by a team of active agents. The problem of shepherding and the difficulties that arise with the increasing number of data describing the location of agents have been described. Several methods for reducing the dimensionality of data are presented. Selected autoencoding method using a Restricted Boltzmann Machine is...

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  • PTR-MS and GC-MS as complementary techniques for analysis of volatiles: A tutorial review

    This tutorial review is a critical commentary on the combined use of two instrumental analytical techniques, namely GC-MS and PTR-MS. The first mention of such an analytical approach likely appeared after the year 2000 and despite many advantages, it has not been applied very often. Therefore, the aim of this article is to elaborate on the concept of their combined use and to provide a curse tutorial for those considering taking...

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  • Speace frienly for the blind = Przestrzeń przyjazna dla niewidomych

    Publikacja

    - Rok 2012

    The article presents issues connected with accessibility of public space for people with eyesight disabilities. The use of the extravisual spatial stimuli in shaping the urban environment has been analysed. Spaces in which musltisensory spatial reception is feasible become user-friendly, as they come to meet the changing needs of their users. The article introduces a system of textures aiding spatial orientation, navigation and...

  • Leading with Understanding: Cultivating Positive Relationships between Neurotypical Leaders and Neurodivergent Employees

    Publikacja

    Neurodivergent employees have atypical needs that require distinctive leadership approaches. In this study, the specific nature of a relationship between neurodivergent employees and their neurotypical leaders is explored through the lens of the Leader-Member-Exchange (LMX) theory. This two-phased qualitative study builds on 12 semi-structured interviews with neurodivergent employees and an unstructured focus group with 15 individuals...

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  • Family business succession – the practical or also theoretical problem. Bibliometric analysis

    Publikacja

    - Rok 2020

    Family businesses, in various forms, have existed since societies began to be created. However, family business research has a decidedly shorter tradition. In favorable conditions, family enterprises develop for many generations, and their fate is intertwined with the fate of the families. The topics of family businesses are raised by researchers around the world. Estimates regarding the number of family businesses are a frequent...

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  • Teaching civil engineering in English at Gdansk University of Technology

    The effects of globalization, as well as many possibilities of easy and cheap ways of travelling, have led to the increase in number of different types of university studies conducted in English. This paper describes advantages and disadvantages after seven years of experience of conducting three-semester MSc Studies in Civil Engineering in English at Gdansk University of Technology, Poland. The studies started in 2009 after a...

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  • UNDECLARED WORK IN POLAND CHARACTERISTICS AND PREVALENCE

    Publikacja

    - Ekonomika - Rok 2016

    This article aims to present the significance and prevalence of the phenomenon of undeclared work. First, we discuss the definitional issues of this phenomenon. Then, we present previous estimates on shadow economy and undeclared work in Poland, based on statistics provided by Central Statistical Office and other research entities. Our analysis covers the years 2000–2014. In the last part of the article, we use data from the Labour...

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  • Turbulence model evaluation for numerical modelling of turbulent flow and heat transfer of nanofluids

    Publikacja

    - Applied Mechanics and Materials - Rok 2016

    In this work, Nusselt number and friction factor are calculated numerically for turbulent pipe flow (Reynolds number between 6000 and 12000) with constant heat flux boundary condition using nanofluids. The nanofluid is modelled with the single-phase approach and the simulation results are compared with experimental data. Ethylene glycol and water, 60:40 EG/W mass ratio, as base fluid and SiO2 nanoparticles are used as nanofluid...

  • New potential functions for greedy independence and coloring

    Publikacja

    - DISCRETE APPLIED MATHEMATICS - Rok 2015

    A potential function $f_G$ of a finite, simple and undirected graph $G=(V,E)$ is an arbitrary function $f_G : V(G) \rightarrow \mathbb{N}_0$ that assigns a nonnegative integer to every vertex of a graph $G$. In this paper we define the iterative process of computing the step potential function $q_G$ such that $q_G(v)\leq d_G(v)$ for all $v\in V(G)$. We use this function in the development of new Caro-Wei-type and Brooks-type...

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  • On the Origin of Protein Superfamilies and Superfolds

    Publikacja

    - Scientific Reports - Rok 2015

    Distributions of protein families and folds in genomes are highly skewed, having a small number of prevalent superfamiles/superfolds and a large number of families/folds of a small size. Why are the distributions of protein families and folds skewed? Why are there only a limited number of protein families? Here, we employ an information theoretic approach to investigate the protein sequence-structure relationship that leads to...

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  • Why is TASK Quarterly a Significant Journal to Publish Your Article? —A Bibliometric Analysis of a Scientific and Technical Journal

    Publikacja

    A bibliometric analysis of TASK Quarterly in the years 1997-2021 in terms of various bibliometric indicators was performed to celebrate the 25th anniversary of the publication of the first issue of the journal. The number of publications and citations increased over the mentioned span of years. The leading countries in terms of the greatest number of papers published in TASK Quarterly are Poland, Italy, Germany, Ukraine, USA and...

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  • Benefit of the doubt approach to assessing the research performance of Australian universities

    This paper proposes a benefit of the doubt (BoD) approach to assess the research performance of 37 public Australian universities based on data from 2015. The primary activities of Higher Education institutions are teaching and research, but the prestige of a university depends mainly on the results of its research activities. The BoD method is rooted in the data envelopment analysis methodology, which enables the flexible and...

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  • SPECYFIKA OBLIGACJI ZAMIENNYCH EMITOWANYCH PRZEZ SPÓŁKI PUBLICZNE

    Publikacja

    Upublicznienie rynku instrumentów dłużnych przedsiębiorstw w Polsce umożliwiło spółkom bardziej efektywne pozyskiwanie środków finansowych poprzez zaciąganie długu u wierzycieli detalicznych, równolegle z istniejącą już możliwością pozyskiwania kapitałów własnych. Rynek ten otworzył także spółkom publicznym drogę do emisji obligacji zamiennych, które z kolei bez obecności instrumentów udziałowych emitenta na rynku publicznym, stają...

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  • Average CIT rate in European Union countries in 2008, 2010, 2012, 2014 and 2016 (in%)

    Dane Badawcze
    open access

    The following data presents the average CIT rate in European Union countries between 2008-2016 .

  • Lucyna Nyka prof. dr hab. inż. arch.

    Lucyna Nyka (prof. dr hab. inż. arch.) jest architektem i profesorem na Wydziale Architektury Politechniki Gdańskiej. W latach 2008-2016 pełniła funkcję prodziekana ds. nauki, a od 2016 jest dziekanem Wydziału Architektury.     Zainteresowania badawcze prof. Lucyny Nyki skoncentrowane są wokół kwestii powiązań architektury i wody, przekształceń terenów nadwodnych oraz urbanistycznych krajobrazów. Jest autorem i współautorem wielu...

  • Comparative study on total nitrogen prediction in wastewater treatment 1 plant and effect of various feature selection methods on machine learning algorithms performance

    Publikacja

    - Journal of Water Process Engineering - Rok 2021

    Wastewater characteristics prediction in wastewater treatment plants (WWTPs) is valuable and can reduce the number of sampling, energy, and cost. Feature Selection (FS) methods are used in the pre-processing section for enhancing the model performance. This study aims to evaluate the effect of seven different FS methods (filter, wrapper, and embedded methods) on enhancing the prediction accuracy for total nitrogen (TN) in the WWTP...

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  • Evaluation of wow defects based on tonal components detection and tracking

    Publikacja

    Referat przedstawia opis metody wyznaczania charakterystyki pasożytniczego kołysania dźwięku. W metodzie wykorzystuje się informacje o zmianach tonalnych składowych dźwięku wyszukiwanych w kolejnych ramkach czasowych. Komponenty tonalne z poszczególnych ramek łączone są w ścieżki. Na podstawie tych trajektorii tworzona jest krzywa PVC obrazująca pasożytnicze zmiany dźwięku. Krzywa PVC może być wykorzystana do usunięcia pasożytniczego...

  • Efektywna metoda wyznaczania trasy statków żaglowych

    Publikacja

    - Rok 2016

    Zaproponowano metodę wyznaczania suboptymalnej trasy statków żaglowych poruszających się w ograniczonym akwenie morskim. Uwzględniono przy tym dynamikę tego środowiska w tym warunki pogodowe oraz charakterystyki prędkościowe statków żaglowych. Jako kryterium optymalizacji przyjęto czas żeglugi T oraz liczbę wykonanych manewrów ω. Zaprojektowano heurystyczny algorytm oraz odpowiednią aplikację wyznaczania trasy dla ustalonych punktów...

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  • Video content analysis in the urban area telemonitoring system

    Publikacja

    The task of constant monitoring of video streams from a large number of cameras and reviewing the recordings in order to find a specified event requires a considerable amount of time and effort from the system operators and it is prone to errors. A solution to this problem is an automatic system for constant analysis of camera images being able to raise an alarm if a predefined event is detected. The chapter presents various aspects...

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  • CROWDFUNDING OF RESEARCH PROJECTS IN POLAND

    Publikacja

    Crowdfunding recently became a very popular way of funding, which allows funding almost everything, from minor personal projects to expensive commercial ones, as long as we can find investors. It may also be a new opportunity for entrepreneurial researchers, who may attract capital investment in companies that are promised to own developed technologies. Social financing of science is well suited to reduce some of the biggest problems...

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  • Some variations of perfect graphs

    Publikacja

    - Discussiones Mathematicae Graph Theory - Rok 2016

    We consider (ψk−γk−1)-perfect graphs, i.e., graphs G for which ψk(H) =γk−1(H) for any induced subgraph H of G, where ψk and γk−1 are the k -path vertex cover number and the distance (k−1)-domination number, respectively. We study (ψk−γk−1)-perfect paths, cycles and complete graphs for k≥2. Moreover, we provide a complete characterisation of (ψ2−γ1)-perfect graphs describing the set of its forbidden induced subgraphs and providing...

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  • Trade differentiation and the characteristics of new imported and exported products - international panel data analysis

    Drawing on o large panel of international economies we have shown how the set of imported and exported products evolves in economic growth process. Strong activity at the extensive margin, manifested through the rise in the number of active export and import lines, is typical for early stages of development. Trade diversification tendency, typical for a predominant mass of observations in our panel, is associated with changes in...

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  • A Dual-Polarized 39 GHz 4x4 Microstrip Antenna Array for 5G MU-MIMO Airflight Cabin Connectivity

    Publikacja

    This paper presents the design, fabrication, and experimental validation of a 39 GHz dual-polarized 4x4 microstrip antenna array. The array consists of 16 slot coupled circular microstrip patches, fed through SMPS connectors. The procedure requiring a reduced number of cables for measurement of the uniformly excited antenna array is also presented. The array exhibits 18 dBi peak gain and 2.9 GHz reflection bandwidth and is intended...

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  • Jakub Miler dr inż.

    Kariera akademicka: 2000: mgr inż. Wydział ETI, Politechnika Gdańska, praca pt. "Computer system for supporting risk management in a software engineering project", promotor prof. Janusz Górski 2005: dr inż. Wydział ETI, Politechnika Gdańska, rozprawa pt. "A Method of Software Project Risk Identification and Analysis", obroniona z wyróżnieniem, dziedzina nauki techniczne, dyscyplina informatyka, promotor prof. Janusz Górski Zainteresowania...

  • EMISJA AKUSTYCZNA JAKO SYGNAŁ DIAGNOSTYCZNY ODWZOROWUJĄCY ZMĘCZENIOWE ZUŻYCIE WARSTW ŚLIZGOWYCH PANWI ŁOŻYSK GŁÓWNYCH I KORBOWYCH SILNIKÓW O ZAPŁONIE SAMOCZYNNYM

    Publikacja

    W artykule przedstawiono wyniki badań laboratoryjnych, z których wynika, że emisja akustyczna (EA) może być uznana za sygnał diagnostyczny, przydatny do identyfikacji stanu technicznego łożysk głównych i korbowych okrętowych silników o zapłonie samoczynnym. Wykazano w nim bowiem, że parametry emisji akustycznej takie jak: czas rejestracji, energia sygnału, amplituda sygnału, ilość przekroczeń poziomu dyskryminacji, czas narastania,...

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  • The searchlight problem for road networks

    Publikacja

    - THEORETICAL COMPUTER SCIENCE - Rok 2015

    We consider the problem of searching for a mobile intruder hiding in a road network given as the union of two or more lines, or two or more line segments, in the plane. Some of the intersections of the road network are occupied by stationary guards equipped with a number of searchlights, each of which can emit a single ray of light in any direction along the lines (or line segments) it is on. The goal is to detect the intruder,...

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  • Ryszard Woźniak dr inż.

    Jest absolwentem Wydziału Mechanicznego i Organizacji Politechniki Lubelskiej, gdzie w 1984 uzyskał tytuł magistra inżyniera mechanika w zakresie Mechaniki specjalności Samochody i Ciągniki. W 2002 roku w Politechnice Gdańskiej obronił pracę doktorską na temat: "Hałas opon w warunkach występowania znacznych sił stycznych w strefie styku opony z jezdnią" i uzyskał stopień naukowy doktora nauk technicznych w zakresie budowy i eksploatacji...

  • Association of Genes Related to Oxidative Stress with the Extent of Coronary Atherosclerosis

    Publikacja

    - Life - Rok 2020

    Oxidative stress is believed to play a critical role in atherosclerosis initiation and progression. In line with this, in a group of 1099 subjects, we determined eight single nucleotide polymorphisms (SNPs) related to oxidative stress (PON1 c.575A>G, MPO c.463G>A, SOD2 c.47T>C, GCLM c.590C>T, NOS3 c.894G>T, NOS3 c.786T>C, CYBA c.214C>T, and CYBA c.932A>G) and assessed the extent of atherosclerosis in coronary arteries based on...

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  • Measured and predicted freeze-thaw days frequencies in climate change conditions in central Poland

    Publikacja

    - PeerJ - Rok 2021

    The rate of progression of geomorphological phenomena is greatly influenced by freeze-thaw processes. In the face of air temperature increasing over the past few decades, a question of the future impact of these processes arises, notably in the temperate and cold climate zones. Using the mean, maximum and minimum daily air temperature data in the period 1951–2018 obtained from three weather stations located in the vicinity of Jeziorsko...

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  • Analytical ‘Steady-State’-Based Derivation and Clarification of the Courant-Friedrichs-Lewy Condition for Pipe Flow

    This article addresses the problem of choosing the optimal discretization grid for emulating fluid flow through a pipeline. The aggregated basic flow model is linearized near the operating point obtained from the steady state analytic solution of the differential equations under consideration. Based on this model, the relationship between the Courant number (μ) and the stability margin is examined. The numerically set coefficient...

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  • Contact angle of the ferronanofluid and influence of the magnetic field on the drying droplet

    Publikacja
    • R. Mulka
    • B. Zajączkowski
    • E. Neuber
    • M. Buschmann

    - International Journal of Thermofluids - Rok 2022

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  • Hybrid dynamically balanced saw frame drive

    W pilarkach ramowych, w których rama piłowa jest napędzana poprzez mechanizm korbowy, generowana przez ramę piłową siła bezwładności oddziaływuje na fundament pilarki oraz na jej układ napędowy. W niniejszym artykule przedstawiono sposób eliminacji tych niekorzystnych zjawisk. Autorzy zaprezentowali dynamicznie wyrównoważony hybrydowy układ napędu ramy piłowej, w którym występuje akumulator energii kinetycznej przyłączony równolegle...

  • Multi-agent large-scale parallel crowd simulation

    Publikacja

    - Rok 2017

    This paper presents design, implementation and performance results of a new modular, parallel, agent-based and large scale crowd simulation environment. A parallel application, implemented with C and MPI, was implemented and run in this parallel environment for simulation and visualization of an evacuation scenario at Gdansk University of Technology, Poland and further in the area of districts of Gdansk. The application uses a...

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  • Performance Assessment of Using Docker for Selected MPI Applications in a Parallel Environment Based on Commodity Hardware

    In the paper, we perform detailed performance analysis of three parallel MPI applications run in a parallel environment based on commodity hardware, using Docker and bare-metal configurations. The testbed applications are representative of the most typical parallel processing paradigms: master–slave, geometric Single Program Multiple Data (SPMD) as well as divide-and-conquer and feature characteristic computational and communication...

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  • CSMA/CA game in an ad hoc network with self otimising stations.

    Publikacja

    - Rok 2003

    Protokoły dostępu do medium transmisyjnego w bezprzewodowych sieciach ad hoc wykorzystują mechanizm CSMA/CA. Protokół ten nie zapewnia sprawiedliwego podziału pasma w środowiskach ze stacjami wykazującymi zachowania niekooperacyjne przy niewielkiej możliwości ich identyfikacji i karania. W pracy rozważa się modyfikacje algorytmu ekspansji okna rywalizacji po kolizji ramek RTS oraz omawia możliwe zabezpieczenia natury administracyjnej,...

  • The database of odd algebraic periods for quasi-unipotent self-maps of a space having the same homology group as the connected sum of g tori

    Dane Badawcze
    open access

    The dataset consists of 20 files indexed by numbers g=1,...,20. Each file provides sets of odd algebraic periods for all quasi-unipotent self-maps of a space having the same homology groups as the connected sum of g tori. Let us remark that each data set covers all algebraical restrictions that come from zeta functions for the sets of  minimal  Lefschetz...

  • Zbigniew Sikora prof. dr hab. inż.

    Osoby