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Iterative Reconstruction for Transmission Tomography on GPU Using Nvidia CUDA

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Tsinghua Science and Technology 2010年第1期15卷 11-16页

作者： Damien Vintache Bernard Humbert David Brasse institut pluridisciplinaire hubert curien CNRS/IN2P323 rue du Loess BP28 67037 StrasbourgFrance

The iterative reconstruction algorithms for X-ray CT image reconstruction suffer from their high computational cost. Recently Nvidia releases common unified device architecture （CUDA）, allowing developers to access to the processing power of Nvidia graphical processing units （GPUs）, in order to perform general purpose computations. The use of the GPU, as an alternative computation platform, allows decreasing processing times, for parallel algorithms. This paper aims to demonstrate the feasibility of such an implementation for the iterative image reconstruction. The ordered subsets convex （OSC） algorithm, an iterative reconstruction algorithm for transmission tomography, has been developed with CUDA. The performances have been evaluated and compared with another implementation using a single CPU node. The result shows that speed-ups of two orders of magnitude, with a negligible impact on image accuracy, have been observed.

关键词： tomography image reconstruction parallel processing

A reference voltage in capacitor–resister hybrid SAR ADC for front-end readout system of CZT detector

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Journal of Semiconductors 2016年第1期37卷 113-118页

作者：刘伟魏廷存李博杨利锋胡永才 School of Computer Science and Technology Northwestern Polytechnical University Xi'an 710072 China institute pluridisciplinaire hubert curien Strasbourg France

An on-chip reference voltage has been designed in capacitor-resister hybrid SAR ADC for CZT detec- tor with the TSMC 0.35 μm 2P4M CMOS process. The voltage reference has a dynamic load since using variable capacitors and resistances, which need a large driving ability to deal with the current related to the time and sampling rate. Most of the previous articles about the reference for ADC present only the bandgap part for a low temperature coefficient and high PSRR. However, it is not enough and overall, it needs to consider the output driving ability. The proposed voltage reference is realized by the band-gap reference, voltage generator and output buffer. Apart from a low temperature coefficient and high PSRR, it has the features of a large driving ability and low power con- sumption. What is more, for CZT detectors application in space, a radiation-hardened design has been considered. The measurement results show that the output reference voltage of the buffer is 4.096 V. When the temperature varied from 0 to 80 ℃, the temperature coefficient is 12.2 ppm/℃. The PSRR was -70 dB @ 100 kHz. The drive current of the reference can reach up to 10 mA. The area of the voltage reference in the SAR ADC chip is only 449 × 614μm2. The total power consumption is only 1.092 mW.

关键词： reference voltage SAR ADC CZT detector

Experimental and Simulated Effective Dose for Some Building Materials in France

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World Journal of Nuclear Science and Technology 2013年第2期3卷 41-45页

作者： Samir Dziri Abdellatif Nachab Abdelmjid Nourreddine Addil Sellam Dominique Gelus Groupe RaMsEs Institut Pluridisciplinaire Hubert Curien (IPHC) Université de Strasbourg Strasbourg France

The specific radioactivity of several building materials used in France, which is considered a direct exposure to radiation, has been assessed by γ-ray spectrometry. Corrected for coincidence summing and self-absorption effects, the values for 226Ra, 232Th and 40K were in the ranges 4 - 56, 3 - 72 and 9 - 1136 Bq·kg-1, respectively. The samples were found to have radium-equivalent activities between 5 and 245 Bq·kg-1. Values of 0.02 - 0.67 for the external and 0.03 - 0.82 for the internal hazard indexes were estimated. The calculated absorbed dose in air agrees closely with MCNPX simulations. The conversion of absorbed dose to annual effective dose gave values between 0.03 - 1.09 mSv·y-1. All these values are below action limits recommended by the International Commission on Radiological Protection. The materials examined would not contribute a significant radiation exposure for an occupant and thus are acceptable for construction.

关键词： Building Materials Hazard Indexes Radium-Equivalent Absorbed Dose Annual Effective Dose MCNPX

A longitudinal network analysis of social dynamics in rooks corvus frugilegus： repeated group modifications do not affect social network in captive rooks

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Current Zoology 2017年第5期63卷 379-388页

作者： Palmyre H. BOUCHERIE Sebastian SOSA Cristian PASQUARETTA Valerie DUFOUR institut pluridisciplinaire hubert curien University of Strasbourg 23 rue Becquerel 67087 Strasbourg France Centre National de la Recherche Scientifique UMR 7178 67087 Strasbourg France Formerly affiliated with Grupo de Conducta Adaptativa e Interacci6n Psychology Faculty University of Barcelona 08035 Barcelona Spain

Numerous studies have investigated the remarkable variation of social features and the resulting structures across species. Indeed, relationships are dynamic and vary in time according to various factors such as environmental conditions or individuals attributes. However, few studies have investigated the processes that stabilize the structures within a given species, and the behavioral mechanisms that ensure their coherence and continuity across time. Here, we used a dynamic actor-based model, RSiena, to investigate the consistency of the temporal dynamic of relationships of a group of captive rooks facing recurrent modifications in group composition （i.e., the loss and introduction of individuals）. We found that changes in relationships （i.e., formation and removal） followed consistent patterns regardless of group composition and sex-ratio. Rooks preferentially interacted with paired congeners （i.e., unpopular attachment） and were more likely to form rela- tionships with individuals bonded to a current social partner （i.e., ＂friends of friends＂, or triadic closure）. The sex of individuals had no effect on the dynamic of relationships. This robust behav- ioral mechanisms formed the basis of inter-connected networks, composed of sub-structures of in- dividuals emerging from the enmeshment of dyadic and triadic motifs. Overall, the present study reveals crucial aspects of the behavioral mechanisms shaping rooks social structure, suggesting that rooks live in a well-integrated society, going far beyond the unique monogamous pair-bond.

关键词： corvids preferential attachment social interactions social network analysis temporal dynamics triadic closure.

High pt and photon physics with ALICE at LHC

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Chinese Physics C 2010年第9期34卷 1383-1386页

作者：周代翠万仁卓毛亚显 Y.Schutz 王梦亮马科王亚平殷中宝蔡勖 Y.Kharlov G.Conesa C.Roy institute of Particle Physics Huazhong Normal UniversityKey Laboratory of Quark & Lepton Physics (Ministry of Education) institute pluridisciplinaire hubert curien University of Strasbourg Laboratoire de Physique Subatomique et de Cosmologie CERN institute for High Energy Physics(Russia)

ALICE,A Large Ion Collider Experiment,is dedicated to study the QCD matter at extreme high temperature and density to understand the Quark Gluon Plasma （QGP） and phase ***-transversemomentum photons and neutral mesons from the initial hard scattering of partons can be measured with ALICE calorimeters,PHOS （PHOton Spectrometer） and EMCAL （ElectroMagnetic CALorimeter）.Combing the additional central tracking detectors,the γ-jet and π 0-jet measurements thus can be *** measurements offer us a sensitive tomography probe of the hot-dense medium generated in the heavy ion *** this paper,high p T and photon physics is discussed and the ALICE calorimeters capabilities of high-transverse-momentum neutral mesons and γ-jet measurements are presented.

关键词： ALICE experiment PHOS EMCAL Jet quenching γ-jet measurement

Excitation and relaxation dynamics in ultrafast laser irradiated optical glasses

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High Power Laser Science and Engineering 2016年第4期4卷 1-8页

作者： C.Mauclair A.Mermillod-Blondin K.Mishchik J.Bonse A.Rosenfeld J.P.Colombier R.Stoian Laboratoire hubert curien UMR 5516 CNRSUniversité de LyonUniversité Jean Monnet Max-Born-institut für Nichtlineare Optik und Kurzzeitspektroskopie Bundesanstalt für Materialforschung und-prüfung (BAM)

We discuss the dynamics of ultrashort pulsed laser excitation in bulk optical silica-based glasses(fused silica and borosilicate BK7) well-above the permanent modification threshold. We indicate subsequent structural and thermomechanical energy relaxation paths that translate into positive and negative refractive index changes, compression and rarefaction zones. If fast electronic decay occurs at low excitation levels in fused silica via self-trapping of excitons,for carrier densities in the vicinity of the critical value at the incident wavelength, persistent long-living absorptive states indicate the achievement of low viscosity matter states manifesting pressure relaxation, rarefaction, void opening and compaction in the neighboring domains. An intermediate ps-long excited carrier dynamics is observed for BK7 in the range corresponding to structural expansion and rarefaction. The amount of excitation and the strength of the subsequent hydrodynamic evolution is critically dependent on the pulse time envelope, indicative of potential optimization schemes.

关键词： carrier plasmas glasses pulse shaping refractive index engineering ultrafast laser excitation

Supporting flexible regulation of crisis management by means of situated artificial institution

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Frontiers of Information Technology & Electronic Engineering 2016年第4期17卷 309-324页

作者： Maiquel DE BRITO Lauren THEVIN Catherine GARBAY Olivier BOISSIER Jomi Fred HUBNER Federal University of Santa Catarina UFSC/CTC/DAS/PPGEAS-PO Box 476FlorianopolisSC 88040-900Brazil LIG/Universite de Grenoble Grenoble 38041France Laboratoire hubert curien UMR CNRS 5516 Institut Henri FayolMINES Saint-EtienneSaint-Etienne 42023France

This paper highlights the use of situated artificial institution(SAI) within a hybrid, interactive,normative multi-agent system to regulate human collaboration in crisis management. Norms regulate the actions of human actors based on the dynamics of the environment in which they are situated. This dynamics results from both environment evolution and actors' actions. Our objective is to situate norms in the environment in order to provide a context-aware crisis regulation. However, this coupling must be a loose one to keep both levels independent and easyto-change in order to face the complex and changing crisis situations. To that aim, we introduce a constitutive level between environmental and normative states providing a loose coupling of normative regulation with environment evolution. Norms are thus no more referring to environmental facts but to status functions, i.e., the institutional interpretation of environmental facts through constitutive rules. We present how this declarative and distinct SAI modelling succeeds in managing the crisis with a context-aware crisis regulation.

关键词： Situated artificial institutions(SAIs) Normative system Tangible interaction Crisis management

Natural Radioactivity Measurement and Dose Assessment in Soil Samples from Some Selected Areas of Mali

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World Journal of Nuclear Science and Technology 2019年第2期9卷 67-73页

作者： Issiaka Traoré Abdramane Ba Abdel Mjid Nourreddine Département de Physique Université des Sciences des Techniques et Technologies de Bamako Bamako Mali institut pluridisciplinaire hubert curien (IPHC) Université de Strasbourg Strasbourg France

This is the first time that a study applies the gamma ray spectroscopy using a high purity germanium to evaluate the terrestrial gamma radiation level by detector in selected regions of Mali. The results reveal that the activity concentrations of naturally occurring 226Ra, 232Th and 40K radionuclides ranges between respectively 17.26 ±1.81 and 105.43 ±10.36;20.41 ±2.52 and 180.85 ±19.69;41.33 ±8.26 and 627.63 ±85.62 Bq⋅kg−1. The measures of radium equivalent activity (Raeq), absorbed dose rates (ADR), annual effective dose rate (AEDR), external hazard index (Hex), internal hazard index (Hin) and excess lifetime cancer risk (ELCR) were evaluated. Some of the obtained values exceed the recommended safe levels. Further studies are necessary to constitute a baseline reference data about the terrestrial radiation in Mali.

关键词： Soil Radioactivity Radiological Hazard Population Exposure Gamma Spectrometry Mali

Foreword International Conference on Materials and Energy(ICOME 2021)

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Fluid Dynamics & Materials Processing 2023年第8期19卷 2131-2146页

作者： El Ganaoui Mohammed Bennacer Rachid Fassi-Fehri Omar Benyoussef Abdelilah Petrissans Mathieu Universitéde Lorraine-institut Henri Poincaréde Longwy(IUT) LongwyFrance UniversitéParis-Saclay ENS Paris-SaclayCNRSLMPSGif-sur-YvetteFrance Académie Hassan II des Sciences et Techniques RabatMorocco Universitéde Lorraine-institut hubert curien d’Epinal(IUT) EpinalFrance

The International Conference on Materials and Energy(ICOME)was held in Metz on June 2021 following the earlier successful conferences of the same series held in Tunisia in 2019,Spain in 2018,China in 2017,France in 2016 and Morocco in *** 2021 event should be regarded as a late realization of the ICOME 2020 conferences,which had to be delayed due to the pandemic.A significant number of papers presented in the framework of this conference have been selected for publication in the Fluid Dynamics and Material Processing international peer reviewed Journal given the relevance of the treated subjects to the aims and scope of this journal and the high quality of these *** foreword provides a critical review of the 2021 conference aims in relation to its potential impact on the fields of Materials and Energy and related societal benefits.

关键词： Energy materials processes