236 research outputs found

    P-AMENABLE LOCALLY COMPACT HYPERGROUPS

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    Abstract. Let K be a locally compact hypergroup with left Haar measure and let We say that K is P-amenable if there exists a left invariant mean on C(P 1 (K)), the space of all bounded continuous functions on P 1 (K). In this note, we consider the Pamenability of hypergroups. The P-amenability of hypergroup joins K = H ∨ J where H is a compact hypergroup and J is a discrete hypergroup with H ∩ J = {e} is characterized. It is also shown that Z-hypergroups are P-amenable if Z(K) ∩ G(K) is compact

    Gravitation on a Homogeneous Domain

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    Among all plastic deformations of the gravitational Lorentz vacuum \cite{wr1} a particular role is being played by conformal deformations. These are conveniently described by using the homogeneous space for the conformal group SU(2,2)/S(U(2)x U(2)) and its Shilov boundary - the compactified Minkowski space \tilde{M} [1]. In this paper we review the geometrical structure involved in such a description. In particular we demonstrate that coherent states on the homogeneous Kae}hler domain give rise to Einstein-like plastic conformal deformations when extended to \tilde{M} [2].Comment: 10 pages, 1 figure; four misprints in the original version corrected: one lacking closing parenthesis, two letters, and an overall sign in front of the primitive function on p.

    The importance of contextual aspects in the care for patients with functional somatic symptoms

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    Functional somatic symptoms refer to physical symptoms that cannot be (bio) medically explained. The pattern or clustering of such symptoms may lead to functional syndromes like chronic fatigue syndrome, fibromyalgia, irritable bowel syndrome, among many others. Since the underlying pathophysiology remains unknown, several explanatory models have been proposed, nearly all including social and psychological parameters. These models have stimulated effectiveness studies of several psychological and psychopharmacological therapies. While the evidence for their effectiveness is steadily growing, effect-sizes are at most moderate and many patients do not benefit. We hypothesize that the context in which interventions for functional somatic symptoms are delivered substantially influences their effectiveness. Although this hypothesis is in line with explanatory models of functional somatic symptoms, to our knowledge, studies primarily focusing on the influence of contextual aspects on treatment outcome are scarce. Contextual research in the field of somatic symptoms has (irrespective whether these symptoms can be medically explained or not), however, just begun and already yielded some valuable results. These findings can be organized according to Duranti's and Goodwin's theoretical approach to context in order to substantiate our hypothesis. Based on this approach, we categorized empirical findings in three contextual aspects, i.e. 1) the setting, 2) the behavioural environment, and 3) the language environment. Collectively, some support is found for the fact that early identification of patients with functional somatic symptoms, starting treatment as soon as possible, having a neat appearance and an organized office interior, a warm and friendly nonverbal approach and a language use without defensiveness are contextual parameters which enhance the assessment by the patient of the physician's competence to help. Nonetheless, in vivo studies addressing the most aspects, i.e. nonverbal behaviour and language, are needed for better understanding of these contextual aspect. Moreover, future research should address to what extent optimizing contextual aspects improve care for functional somatic symptoms

    A transient formulation of Newton’s cooling law for spherical bodies

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    Newton's law of cooling is shown to underestimate the heat flux between a spherical body (droplet) and a homogeneous gas after this body is suddenly immersed into the gas. This problem is rectified by replacing the gas thermal conductivity by the effective thermal conductivity. The latter reduces to the gas thermal conductivity in the limit of t→ϱ, but can be substantially higher in the limit of t→0. In the case of fuel droplet heating in a medium duty truck Diesel engine the gas thermal conductivity may need to be increased by more than 100 percent at the initial stage of calculations to account for transient effects during the process of droplet heating

    Finding Homogeneity in Heterogeneity—A New Approach to Quantifying Landscape Mosaics Developed for the Lao PDR

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    A key challenge for land change science in general and research on swidden agriculture in particular, is linking land cover information to human–environment interactions over larger spatial areas. In Lao PDR, a country facing rapid and multi-level land change processes, this hinders informed policy- and decision-making. Crucial information on land use types and people involved is still lacking. This article proposes an alternative approach for the description of landscape mosaics. Instead of analyzing local land use combinations, we studied land cover mosaics at a meso-level of spatial scale and interpreted these in terms of human–environmental interactions. These landscape mosaics were then overlaid with population census data. Results showed that swidden agricultural landscapes, involving 17% of the population, dominate 29% of the country, while permanent agricultural landscapes involve 74% of the population in 29% of the territory. Forests still form an important component of these landscape mosaics

    An IAEA Multi-technique X-ray Spectrometry End-station at Elettra Sincrotrone Trieste: Benchmarking Results and Interdisciplinary Applications

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    The International Atomic Energy Agency (IAEA) jointly with the Elettra Sincrotrone Trieste (EST) operates a multipurpose X-ray spectrometry endstation at the X-ray Fluorescence beamline (10.1L). The facility has been available to external users since the beginning of 2015 through the peer-review process of EST. Using this collaboration framework, the IAEA supports and promotes synchrotron-radiation-based research and training activities for various research groups from the IAEA Member States, especially those who have limited previous experience and resources to access a synchrotron radiation facility. This paper aims to provide a broad overview about various analytical capabilities, intrinsic features and performance figures of the IAEA X-ray spectrometry endstation through the measured results. The IAEA-EST endstation works with monochromatic X-rays in the energy range 3.7-14keV for the Elettra storage ring operating at 2.0 or 2.4GeV electron energy. It offers a combination of different advanced analytical probes, e.g. X-ray reflectivity, X-ray absorption fine-structure measurements, grazing-incidence X-ray fluorescence measurements, using different excitation and detection geometries, and thereby supports a comprehensive characterization for different kinds of nanostructured and bulk materials.A broad overview of the various analytical capabilities, intrinsic features and performance figures of the IAEA X-ray spectrometry endstation operated at the X-ray Fluorescence beamline of Elettra Sincrotrone Trieste is given, and different applications are demonstrated to familiarize the user community with the applicable intersdisciplinary research.Fil: Karydas, A.. International Atomic Energy Agency; Austria. National Centre for Scientific Research "Demokritos"; GreciaFil: Czyzycki, M.. International Atomic Energy Agency; Austria. AGH University of Science and Technology. Faculty of Physics and Applied Computer Science ; PoloniaFil: Leani, Juan Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentina. International Atomic Energy Agency; AustriaFil: Migliori, A.. International Atomic Energy Agency; Austria. Nuclear Spectrometry And Appications Lab, Iaea. Onu; AustriaFil: Osán, J.. Hungarian Academy of Sciences Centre for Energy Research; Hungría. International Atomic Energy Agency; AustriaFil: Bogovac, M.. International Atomic Energy Agency; AustriaFil: Wrobel, P.. AGH University of Science and Technology. Faculty of Physics and Applied Computer Science ; PoloniaFil: Vakula, N.. International Atomic Energy Agency; AustriaFil: Padilla Alvarez, R.. International Atomic Energy Agency; AustriaFil: Menk, Ralf Hendrik. Elettra-Sincrotrone Trieste SCpA di Interesse Nazionale; Italia. University of Saskatchewan; CanadáFil: Gol, M. G.. Iranian Light Source Facility; IránFil: Antonelli, M.. Istituto Nazionale di Fisica Nucleare; Italia. Elettra-Sincrotrone Trieste SCpA di Interesse Nazionale; ItaliaFil: Tiwari, M. K.. Raja Ramanna Centre for Advanced Technology; IndiaFil: Caliri, C.. Istituto Nazionale di Fisica Nucleare; ItaliaFil: Vogel Mikuš, K.. Jozef Stefan Institute; Eslovenia. University of Ljubljana; EsloveniaFil: Darby, I.. Elettra-Sincrotrone Trieste SCpA di Interesse Nazionale; Italia. International Atomic Energy Agency; AustriaFil: Kaiser, R.. International Atomic Energy Agency; Austri

    Secondary education reform in Lesotho and Zimbabwe and the needs of rural girls: Pronouncements, policy and practice

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    Analysis of the educational needs of rural girls in Lesotho and Zimbabwe suggests a number of shortcomings in the current form of secondary education, and ways in which it might be modified so as to serve this sizeable group of students better. Several of the shortcomings, notably in relation to curricular irrelevance and excessive focus on examinations, have long been recognised, including by politicians. Yet political pronouncements are seldom translated into policy, and even where policy is formulated, reforms are seldom implemented in schools. This paper makes use of interviews with educational decision-makers in the two southern African countries and a range of documentary sources to explore why, despite the considerable differences between the two contexts, much needed educational reforms have been implemented in neither

    A survey of free software for the design, analysis, modelling, and simulation of an unmanned aerial vehicle

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    The objective of this paper is to analyze free software for the design, analysis, modelling, and simulation of an unmanned aerial vehicle (UAV). Free software is the best choice when the reduction of production costs is necessary; nevertheless, the quality of free software may vary. This paper probably does not include all of the free software, but tries to describe or mention at least the most interesting programs. The first part of this paper summarizes the essential knowledge about UAVs, including the fundamentals of flight mechanics and aerodynamics, and the structure of a UAV system. The second section generally explains the modelling and simulation of a UAV. In the main section, more than 50 free programs for the design, analysis, modelling, and simulation of a UAV are described. Although the selection of the free software has been focused on small subsonic UAVs, the software can also be used for other categories of aircraft in some cases; e.g. for MAVs and large gliders. The applications with an historical importance are also included. Finally, the results of the analysis are evaluated and discussed—a block diagram of the free software is presented, possible connections between the programs are outlined, and future improvements of the free software are suggested. © 2015, CIMNE, Barcelona, Spain.Internal Grant Agency of Tomas Bata University in Zlin [IGA/FAI/2015/001, IGA/FAI/2014/006
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