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Journal of Thermal Science 2017年第1期26卷 54-59页

作者： Jaison Philip Abhilash Suryan T.V Sanand P Unnikrishnan Nair S. Sivakumar Department of Mechanical Engineering College of Engineering Trivandrum Kerala India 695016 Turbo Pump Division LPSC Valiamala Trivandrum Kerala. Department of Mechanical Engineering Rajadhani Institute Engineering & Technology Trivandrum Kerala India

Fluid flow in a screw pump which rotates at very high angular velocity is numerically analyzed. In the present study, fluid flow in screw pumps under high Reynolds number, of the order of 105, is considered. Screw pump has two major elements, a plain shroud which is a stationary element and a rotating hub with helical grooves contained within the shroud. In this paper, three variants of hubs with different number of thread starts numbering six, eight and twelve in combination with a plain shroud is studied. Each of the three possible combinations are analyzed on the basis of pressure rise developed, efficiency and shaft power. It was seen that pressure rise, efficiency and shaft power increases as the number of threads increases in the range of mass flow rates studied.

关键词： Screw pump, Turbulent flow, Angular velocity

Model-independent constraints on spin observables

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Chinese Physics C 2009年第12期33卷 1153-1158页

作者： Jean-Marc Richard Xavier Artru Mokhtar Elchikh Jacques Soffer Oleg Teryaev lpsc Université Joseph Fourier CNRS/IN2P3 INPG Grenoble France Université de Lyon IPNL Université Lyon 1 and CNRS/IN2P3 Villeurbanne France Université des Sciences et de Technologie d'Oran El Menauoer Oran Algeria Physics Department Temple University Philadelphia PA 19122 -6082 USA Bogoliubov Laboratory of Theoretical Physics JINR 141980 Dubna Russia

We discuss model-independent constraints on spin observables in exclusive and inclusive reactions, with special attention to the case of photoproduction.

关键词： spin observables positivity exclusive reactions inclusive reactions

Recent Developments on the Phoenix ECR Booster at ISOLDE,CERN

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Chinese Physics C 2007年第S1期31卷 216-218页

作者： M.Marie-Jeanne P.Delahaye CERN GenevaCH-1211Switzerland LPSCGrenobleF-38000France Université Joseph FourierGrenobleF-38000France CERN GenevaCH-1211Switzerland

At ISOLDE (CERN),an on-line test bench is dedicated to charge breeding experiments with a 14GHz Phoenix ion source,for the investigation of the 1+→n+ scenario at next generation ISOL-type *** year,various technical developments have been undertaken for intensifying the tests of the on- line performances of the booster with a high diversity of stable and radioactive ion *** contribution will present an overview of the latest developments,the current challenges,and some perspectives for the future use of the Phoenix booster for physics experiments at ISOLDE.

关键词： ion sources charge breeding mass and energy spectrometer

ECRIS Charge Breeding at ISAC

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Chinese Physics C 2007年第S1期31卷 211-215页

作者： F.Ames R.Baartman P.Bricault K.Jayamanna M.McDonald M.Olivo P.Schmor D.H.L.Yuan T.Lamy TRIUMF 4004 Wesbrook MallVancouverBCV6t 2A3Canada lpsc UJF-IN2P3-CNRS53 Av.Des Martyrs38026 GrenobleFrance

An ECR ion source for charge breeding of radioactive ions from the ISAC facility at TRIUMF has been set up at a test *** has been operated with different ion sources for the injection of singly charged ions and the efficiency,breeding time and emittance have been determined for several elements.A maximum efficiency of more than 6% for the breeding of Kr^(12+) has been achieved so *** the charge exchange of Rb and Cs ions in the range of 10+ to 23+ with residual gas molecules in the transport beam lines has been *** absolute values for the cross sections at 10—15 q keV agree with predictions extrapolated from lower charge states but the strong dependence on the ionization energy of the gas molecules could not be verified.

关键词： ECRIS charge breeding radioactive ions charge exchange

On Energy-Efficient Time Synchronization for Wireless Sensors under Large-Scale and Small-Scale Fading Effects

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Wireless Sensor Network 2013年第10期5卷 181-193页

作者： Pablo Briff Ariel Lutenberg Leonardo Rey Vega Fabian Vargas CONICET National Scientific and Technical Research Council Buenos Aires Argentina lpsc Faculty of Engineering University of Buenos Aires Buenos Aires Argentina Embedded Systems Laboratory Faculty of Engineering University of Buenos Aires Buenos Aires Argentina Embedded Systems Laboratory Faculty of Engineering University of Buenos Aires Buenos Aires Argentina CONICET National Scientific and Technical Research Council Buenos Aires Argentina Signals and Systems for Computing Group Faculty of Engineering Catholic University Porto Alegre Brazil

In this work, the existing trade-off between time synchronization quality and energy is studied for both large-scale and small-scale fading wireless channels. We analyze the clock offset estimation problem using one-way, two-way and N-way message exchange mechanisms affected by Gaussian and exponentially distributed impairments. Our main contribution is a general relationship between the total energy required for synchronizing a wireless sensor network and the clock offset estimation error by means of the transmit power, number of transmitted messages and average message delay, deriving the energy optimal lower bound as a function of the time synchronization quality and the number of hops in a multi-hop network.

关键词： Wireless Sensor Networks Clock Offset Estimation Time Synchronization Wireless Channel Fading

Latest results from GRAAL collaboration

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Chinese Physics C 2009年第12期33卷 1249-1253页

作者： V. Vegna V. Bellini J.P. Bouquet L. Casano A. D'Angelo J.P. Didelez R. Di Salvo A. Fantini D. Franco G. Gervino F. Ghio G. Giardina B. Girolami A. Giusa M. Guidal E. Hourany A.S. Ignatov R. Kunnel A. Lapik A. Lleres P. Levi Sandri F. Mammoliti G. Mandaglio M. Manganaro M. Moricciani A.N. Mushkarenkov V.G. Nedorezov C. Randieri D. Rebreyend N.V. Rudnev G. Russo C. Schaerf M.L. Sperduto M.C. Sutera A.Turinge Dip. di Fisica Università degli Studi di Roma 'Tor Vergata' via della Ricerca Scientifica 1 I-00133 Roma Italy INFN - Sezione di Roma 'Tor Vergata' via della Ricerca Scientifica 1 I-00133 Roma Italy Dip. di Fisica e Astronomia Università di Catania via Santa Sofia 44 I-95123 Catania Italy INFN - Sezione di Catania via Santa Sofia 44 I-95123 Catania Italy lpsc Universit Joseph Fourier Grenoble 1 CNRS/IN2P3 Institut National Polytechnique de Grenoble 53 Avenue des Martyres 38026 Grenoble France IPNO Universit de Paris-Sud 11 CNRS/IN2P3 15 rue Georges Clemenceau 91406 Orsay France Dip. di Fisica Sperimentale Università di Torino via P.Giuria I-00125 Torino Italy INFN - Sezione di Torino via P.Giuria I-00125 Torino Italy Istituto Superiore di Sanità viale Regina Elena 299 I-00161 Roma Italy INFN - Sezione di Roma piazzale Aldo Moro 2 I-00185 Roma Italy Dip. di Fisica Universitàdi Messina salita Sperone 31 I-98166 Messina Italy Institute for Nuclear Research RAS 117312 Moscow Russia INFN - Laboratori Nazionali di Frascati via E.Fermi 40 I-00044 Frascati Italy INFN - Sezione di Catania via Santa Sofia 44 I-95123 Catania Italy

The GRAAL experimental set-up consists of a polarized and tagged photon beam that covers an energy range from a minimum of 600 MeV up to a maximum of 1500 MeV, of a liquid Hydrogen or Deuterium target and of the 4π Lagrange detector optimized for photon detection. It allows the study of pseudo-scalar and vector meson photoproduCtion on the nucleon in the energy range corresponding to the second and the third resonance regions. In the following, the ∑ beam asymmetries in η and π0 photoproduction on quasi-free nucleon are shown. Also single and double polarization observables in K＋A photoproduction on free proton are shown; they are important to confirm the role of new or poorly known resonances in the 1900 MeV mass region.

关键词： polarized photon meson photoproduction polarization observables