Search results for "Plate"

Le plateau du Béage au second âge du Fer (Ardèche) : le site du « Crouzet - La Veysse » et son environnement

2016

National audience; L’opération archéologique au lieu-dit Le Crouzet-La Veysse en haute Ardèche (alt. : 1215 m ; commune du Béage) avait pour objectif de caractériser les indices de site mis au jour lors de travaux agricoles de drainage en janvier 2014 (tessons de céramique d’allure protohistorique). Quatre sondages ont été ouverts en mai 2015 (6,5 m2) et ont permis la mise au jour d'un ensemble de 344 tessons (NMI : 21), ainsi que d’un mobilier lithique consacré à la mouture. Dans les sondages 1 et 2, la disposition de fragments de céramique protohistorique de dimension décimétrique et en connexion suggère la présence de lambeaux de sol archéologique conservés au contact du substrat géologi…

Contextualization of archaeological information using augmented photospheres, viewed with head-mounted displays.

2019

Photospheres, or 360&deg

Plateformisation : quels impacts pour l’expérience ?

2022

Acoustic properties of plates with unevenly distributed macro perforations backed by woven meshes

2012

A hybrid model describing the acoustic properties of plates with macro-perforations that can be unevenly distributed on the plate surface and backed by woven or precision woven meshes with microscopic perforations is proposed. The plate perforations may be of circular or rectangular shapes. Since the perforated plate may not necessarily be considered as an equivalent fluid, its surface impedance is calculated by the Maa model [Noise Control Eng. J. 29, 77-84 (1987)], whereas the Johnson-Champoux-Allard model [J. Appl. Phys. 70, 1975-1979 (1991)] is used for the mesh. It is observed that the absorption of the carrying plate seems to depend on the hydraulic diameter of the perforations and no…

On the measurement and prediction of the sound absorption coefficient of air-cavity backed perforated plates considering the holes interaction effect…

2012

International audience; This paper deals with the measurement and prediction of air cavity backed perforated plates considering the holes interaction effect under relatively low sound excitation. A revised expression for the radiation contribution is proposed to properly account for the holes interaction effect. This expression is integrated in the characteristic impedance expression following Atalla and Sgard [J. Sound Vib. 303, 195-208 (2007)] model. Perforated plate specimens with different centre-to-centre holes distances (pitches) are built and tested using an impedance tube. The particular cases of holes interaction effect with constant low porosity and of holes interaction effect wit…

Sound absorption coefficient of a porous material covered with a low open area perforated plate under high sound excitation

2012

International audience; The sound absorption coefficient of porous materials covered with low open area perforated plate is studied under high sound intensities in the absence of mean flow. The theoretical considerations are based on the equivalent fluid following the Johnson-Champoux-Allard approach and the use of the transfer matrix method. To take into account the high sound levels effects, the air flow resistivity of each layer is modified following the Forchheimer law. Two specimens of perforated plate are built and tested when backed by a polymeric foam and a fibrous material. A specific impedance tube setup is developed for the measurement of the surface acoustic impedance for sound …

Optimization of Passive Constrained Layer Damping (Pcld) Treatments for Vibration Reduction

2015

An efficient method to reduce the frequency averaged transverse vibration level of aplate by optimizing the position of attached passive constrained layer damping PCLD is presented.This method uses a multilayer anisotropic plate model which is an equivalent single layer platemodel (ESL) where transverse shear stresses and displacements are continuous at each layer’sinterfaces. Hence, for a laminate composed of an arbitrary number of layers, all the quantities arerelated to those of the first layer. The optimization process is based on the use of the ESL platemodel combined with the genetic algorithm (GA) and Latin Hypercube Sampling (LHS) algorithmimplemented in a Rayleigh-Ritz resolution p…

Possible Implications for Improved Osteogenesis? The Combination of Platelet-Rich Fibrin With Different Bone Substitute Materials

2021

Bone substitute materials (BSM) are widely used in oral regeneration, but sufficient angiogenesis is crucial for osteogenesis. The combination of BSM with autologous thrombocyte concentrations such as platelet-rich fibrin (PRF) may represent a clinical approach to overcome this limitation. This study analyzes the early influence on osteoblast (HOB) in vitro. Here, four different BSM (allogeneic, alloplastic, and two of xenogeneic origin) were combined with PRF. After the incubation with osteoblasts for 24 h, cell viability, migration, and proliferation were assessed. Next, marker of proliferation, migration, and differentiation were evaluated on gene and protein levels in comparison to the …

Double-application of platelet-rich plasma on bone healing in rabbits

2010

Objective: Platelet-rich plasma (PRP) is considered to enhance bone formation especially at early stages of wound healing, depending on the limited and short life-span of platelets and growth factors. The aim of this study was to evaluate efficacy of double-application of PRP (DA-PRP) on bone healing in a rabbit calvarial defect model. Study design: Twenty-eight rabbits, each had two surgically prepared calvarial bone defects (10mm diameter), were included in this study and randomly divided into six groups. Defects (n=56) were treated with single-application of PRP (SA-PRP)(n=10), SA-PRP and beta-tricalciumphosphate (SA-PRP+TCP)(n=10), DA-PRP (n=8), DA-PRP and beta-tricalciumphosphate (DA-P…

Real-World Data of Anticoagulant Treatment in Non-valvular Atrial Fibrillation

2022

AimsTo assess the impact of anticoagulant treatment on risk for stroke and all-cause mortality of patients with atrial fibrillation using real-world data (RWD).MethodsPatients with prevalent or incident atrial fibrillation were selected throughout a study period of 5 years. Stroke, transitory ischemic attack, hemorrhagic stroke, and all-cause mortality were identified in the claims of the electronic health records (EHRs). Subjects were classified according to the anticoagulant treatment in four groups: untreated, vitamin K antagonists (VKAs), New Oral Anticoagulants (NOACs), and antiplatelet (AP). Risk of events and protection with anticoagulant therapy were calculated by Cox proportional h…