133 research outputs found

    On complex algebras of subalgebras

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    We establish a condition (so called generalized entropic property), equivalent to the fact that for every algebra A from a given variety V, the set of all subalgebras of A is a subuniverse of the complex algebra of A. We investigate the relationship between the generalized entropic property and the entropic law. Further, we study the identities satisfied by the complex algebras of subalgebras of algebras from a variety V.Comment: 19 page

    On complex algebras of subalgebras

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    Let V be a variety of algebras. We establish a condition (so called generalized entropic property), equivalent to the fact that for every algebra A 2 V, the set of all subalgebras of A is a subuniverse of the complex algebra of A. We investigate the relationship between the generalized entropic property and the entropic law. Further, provided the generalized entropic property is satisfied in V, we study the identities satisfied by the complex algebras of subalgebras of algebras from

    Crowdsourcing Question-Answer Meaning Representations

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    We introduce Question-Answer Meaning Representations (QAMRs), which represent the predicate-argument structure of a sentence as a set of question-answer pairs. We also develop a crowdsourcing scheme to show that QAMRs can be labeled with very little training, and gather a dataset with over 5,000 sentences and 100,000 questions. A detailed qualitative analysis demonstrates that the crowd-generated question-answer pairs cover the vast majority of predicate-argument relationships in existing datasets (including PropBank, NomBank, QA-SRL, and AMR) along with many previously under-resourced ones, including implicit arguments and relations. The QAMR data and annotation code is made publicly available to enable future work on how best to model these complex phenomena.Comment: 8 pages, 6 figures, 2 table

    Weyl Algebras and Knots

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    In this paper we push forward results on the invariant F{\cal F}-module of a virtual knot investigated by the first named author where F{\cal F} is the algebra with two invertible generators A,BA,B and one relation A1B1ABB1AB=BA1B1AAA^{-1}B^{-1}AB-B^{-1}AB= BA^{-1}B^{-1}A-A. For flat knots and links the two sides of the relation equation are put equal to unity and the algebra becomes the Weyl algebra. If this is perturbed and the two sides of the relation equation are put equal to a general element, qq, of the ground ring, then the resulting module lays claim to be the correct generalization of the Alexander module. Many finite dimensional representations are given together with calculations.Comment: 18 pages, 5 figures, accepted by Journal of Geometry and Physic

    Electrodiffusion Method of Near-Wall Flow Diagnostics in Microfluidic Systems

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    This paper was presented at the 4th Micro and Nano Flows Conference (MNF2014), which was held at University College, London, UK. The conference was organised by Brunel University and supported by the Italian Union of Thermofluiddynamics, IPEM, the Process Intensification Network, the Institution of Mechanical Engineers, the Heat Transfer Society, HEXAG - the Heat Exchange Action Group, and the Energy Institute, ASME Press, LCN London Centre for Nanotechnology, UCL University College London, UCL Engineering, the International NanoScience Community, www.nanopaprika.eu.The electrodiffusion technique has been mostly used for the near-wall flow diagnostics on large scales. A novel technique for fabrication of plastic microfluidic systems with integrated metal microelectrodes (called technique of sacrificed substrate) enables us to produce microfluidic devices with precisely shaped sensors for wall shear stress measurements. Several micrometer thick gold sensors built-in a plastic substrate exhibit good mechanical resistance and smoothness. Proper functioning of prepared chips with microsensors has been first tested in various calibration experiments (polarization curve, sensor response to polarization set-up, steady flow calibration, temperature dependence of diffusivity). Our first results obtained for separating/reattaching flow behind a backward-facing step and for gas-liquid Taylor flow in microchannels then demonstrate its applicability for the detection of near-wall flow reversal, the delimitation of flow-recirculation zones, and the determination of wall shear stress response to moving bubbles. Other applications of these sensors in microfluidics (e.g. characterization of liquid films, capillary waves, bubbles or drops) can be also envisaged

    Meniscus dynamics in bubble formation : a parametric study

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    This study brings new experimental data on the bubble formation process with a particular focus on the behaviour of the gas–liquid interface (meniscus) inside a transparent orifice on a perforated plate. The meniscus plays an important role by coupling the gas and liquid sides. The goal was to find the effect of five important control parameters on the bubble production and the meniscus behaviour (orifice diameter, plate thickness, gas chamber size, liquid height, and liquid viscosity). The gas input was also varied. Three physical signals were taken in the measurements to extract the information needed (gas pressure in plenum, acoustic pressure in liquid, and video record of meniscus motion). Several relevant quantities were measured to characterize the bubbling process (bubbling period, active orifice time, and periods of meniscus oscillations). The data obtained show how these quantities depend on the control parameters. The recognition of the role of the meniscus dynamics in the gas dispersing process with perforated plates offers a deeper insight into this important and complicated problem

    Проектирование параметров несимметричной тепловой обработки

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    Становский А. Л. Проектирование параметров несимметричной тепловой обработки / А. Л. Становский, Е. Г. Трофименко // Труды Одесского политехнического университета. – 1997. – Вып. 1. – С. 271-274.Розглянуто режими нагріву напівобмеженого тіла крапковим джерелом тепла, який рухається по його поверхні. Досліджено термічні умови, що виникають при такому нагріві плоского об'єкту, та принципи побудови моделі. Визначені параметри прогріву об'єкту до заданої температури.Рассмотрены режимы нагрева полуограниченного тела точечным источником тепла, который движется по его поверхности. Исследовано термические условия, возникающие при таком нагреве плоского объекта, и принципы построения модели. Определены параметры прогрева объекта к заданной температуре.Investigation is given to conditions of heating of a semi- limited body by a point source of heat moving over its surface. Researches were carried out into thermal conditions brought about during such heating of a flat object and principles of model construction. Determined are parameters of object heat-up to preset temperature
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