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Browsing by Subject "Reiknirit"

Browsing by Subject "Reiknirit"

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  • Losievskaja, Elena (Háskólinn í Reykjavík, 2011-01-24)
    This thesis deals with approximation algorithms for the Maximum Independent Set and the Minimum Hitting Set problems on hypergraphs. As a hypergraph is a generalization of a graph, the question is whether the best known approximations on graphs can be ...
  • Kirchhoff, Björn (University of Iceland, School of Engineering and Natural Sciences, Faculty of Physical Sciences, 2021-05-28)
    The oxygen reduction reaction (ORR) is of central importance in the development of more efficient and durable fuel cells and computer simulations can be used to help explain and predict properties of ORR catalysts. In this thesis, various simulation methods ...
  • Cimini, Matteo (Háskólinn í Reykjavík, 2012-12-09)
    Structural Operational Semantics (SOS) is one of the most natural ways for providing programming languages with a formal semantics. Results on the meta-theory of SOS typically (but not solely) say that if the inference rules used in writing the semantic ...
  • Hyytia, Esa; Righter, Rhonda; Bilenne, Olivier; Wu, Xiaohu (Elsevier BV, 2017-09)
    We study the M/D/1 queue when jobs have firm deadlines for waiting (or sojourn) time. If a deadline is not met, a job-specific deadline violation cost is incurred. We derive explicit value functions for this M/D/1 queue that enable the development of ...
  • landeros, alberto; Koziel, Slawomir; Abdel-Fattah, Mohamed (Springer Science and Business Media LLC, 2018-12-13)
    Distribution network reconfiguration (DNR) can significantly reduce power losses, improve the voltage profile, and increase the power quality. DNR studies require implementation of power flow analysis and complex optimization procedures capable of ...
  • Morris, John N.; Berg, Katherine; Howard, Elizabeth P.; Jónsson, Pálmi V.; Craig, Meredith (Elsevier BV, 2019-08)
    Objective: To identify home care clients with substantial functional deficits who had capacity to improve and, thus, for whom recovery goals should be articulated. Design: Retrospective longitudinal analysis of an international home care database. ...
  • Liu, Ying; Cheng, Qingsha S.; Koziel, Slawomir (MDPI AG, 2019-07-11)
    In this article, a generalized sequential domain patching (GSDP) method for efficient multi-objective optimization based on electromagnetics (EM) simulation is proposed. The GSDP method allowing fast searching for Pareto fronts for two and three ...
  • Halldórsson, Magnús M.; Konrad, Christian (Elsevier BV, 2020-04)
    We give a distributed (1+eps)-approximation algorithm for the minimum vertex coloring problem on interval graphs, which runs in the LOCAL model and operates in O((1/eps) log* n) rounds. If nodes are aware of their interval representations, then the ...
  • Halldórsson, Magnús M.; Holzer, Stephan; Markatou, Evangelia Anna; Lynch, Nancy (Elsevier BV, 2020-04)
    We consider the Leader Election Problem in the Signal-to-Interference-plusNoise-Ratio (SINR) model where nodes can adjust their transmission power. We show that in this setting it is possible to elect a leader in two communication rounds, with high ...
  • Bessarab, Pavel; Müller, Gideon Philipp; Lobanov, Igor S.; Rybakov, Filipp N.; Kiselev, Nikolai S.; Jónsson, Hannes; Uzdin, Valery M.; Blügel, Stefan; Bergqvist, Lars; Delin, Anna (Springer Nature, 2018-02-21)
    The skyrmion racetrack is a promising concept for future information technology. There, binary bits are carried by nanoscale spin swirls–skyrmions–driven along magnetic strips. Stability of the skyrmions is a critical issue for realising this technology. ...
  • Gotz, Markus; Cavallaro, Gabriele; Geraud, Thierry; Book, Matthias; Riedel, Morris (Institute of Electrical and Electronics Engineers (IEEE), 2018-11-01)
    Component trees are region-based representations that encode the inclusion relationship of the threshold sets of an image. These representations are one of the most promising strategies for the analysis and the interpretation of spatial information ...
  • Koziel, Slawomir; Bekasiewicz, Adrian (Walter de Gruyter GmbH, 2015-09-23)
    This paper addresses computationally feasible multi-objective optimization of antenna structures. We review two recent techniques that utilize the multi-objective evolutionary algorithm (MOEA) working with fast antenna replacement models (surrogates) ...
  • Aceto, Luca; Fabregas, Ignacio; Garcia-Perez, Alvaro; Ingolfsdottir, Anna; Ortega-Mallen, Yolanda (2019-10-14)
    The nominal transition systems (NTSs) of Parrow et al. describe the operational semantics of nominal process calculi. We study NTSs in terms of the nominal residual transition systems (NRTSs) that we introduce. We provide rule formats for the specifications ...
  • Liu, Bo; Koziel, Slawomir; Ali, Nazar (Oxford University Press (OUP), 2016-11-20)
    Efficiency improvement is of great significance for simulation-driven antenna design optimization methods based on evolutionary algorithms (EAs). The two main efficiency enhancement methods exploit data-driven surrogate models and/or multi-fidelity ...
  • Jónsson, Kristján Valur (Háskólinn í Reykjavík, 2014-02-03)
    In-network aggregation is an important paradigm for current and future networked systems, enabling efficient cooperate processing of aggregate information, while providing sub-linear scalability properties. However, security of this important class of ...
  • Ogurtsov, Stanislav; Kozieł, Sławomir; Bekasiewicz, Adrian (Walter de Gruyter GmbH, 2016-05-31)
    A simulation-based optimization approach to design of phase excitation tapers for linear phased antenna arrays is presented. The design optimization process is accelerated by means of Surrogate-Based Optimization (SBO); it uses a coarse-mesh surrogate ...