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11.
Michalis Christou Maxime Crochemore Tomáš Flouri Costas S. Iliopoulos Jan Janoušek Bořivoj Melichar Solon P. Pissis 《Information Processing Letters》2012,112(24):958-962
We consider the problem of computing all subtree repeats in a given labeled ordered tree. We first transform the tree to a string representing its postfix notation, and then present an algorithm based on the bottom-up technique to solve it. The proposed algorithm consists of two phases: the preprocessing phase and the phase where all subtree repeats are computed. The linear time and space complexity of the proposed algorithm are important parts of its quality. 相似文献
12.
The airflow behavior in a fluidization unit was integrally studied by means of experimental work and computational fluid dynamics simulation. The computational domain included the gas inlet pipe, plenum, perforated plate, fluidization chamber, and air outlet pipe. Different scenarios were simulated to allow distinguishing the best way to represent perforated‐plate distributors and elucidate the impact of the grid design on the fluidization performance. The simulated pressure drop across the distributor and the plenum flow pattern were in concordance with the experimental data. It was found that the distance between the peripheral holes and walls has a great impact on the airflow downstream the distributor. 相似文献
13.
Majid Ahmadi Satyaprakash Sahoo Reza Younesi Anand P. S. Gaur Ram S. Katiyar Maxime J-F Guinel 《Journal of Materials Science》2014,49(17):5899-5909
Tungsten oxide (WO3) nano-ribbons (NRs) were obtained by annealing tungstite (WO3·H2O) NRs. The latter was synthesized below room temperature using a simple, environmentally benign, and low cost aging treatment of precursors made by adding hydrochloric acid to diluted sodium tungstate solutions (Na2WO4·2H2O). WO3 generates significant interests and is being used in a growing variety of applications. It is therefore important to identify suitable methods of production and better understand its properties. The phase transformation was observed to be initiated between 200 and 300 °C, and the crystallographic structure of the NRs changed from orthorhombic WO3·H2O to monoclinic WO3. It was rigorously studied by annealing a series of samples ex situ in ambient air up to 800 °C and characterizing them afterward. A temperature-dependent Raman spectroscopy study was performed on tungstite NRs between minus 180 and 700 °C. Also, in situ heating experiments in the transmission electron microscope allowed for the direct observation of the phase transformation. Powder X-ray diffraction, electron diffraction, electron energy-loss spectroscopy, and X-ray photoelectron spectroscopy were employed to characterize precisely this transformation. 相似文献
14.
Maxime Schwertz Pierre Ranque Sébastien Lemonnier Elodie Barraud Adele Carradò Marie‐France Vallat Michel Nardin 《应用聚合物科学杂志》2015,132(9)
The present study deals with the optimization of polyimide (PI) mechanical properties, obtained by Spark Plasma Sintering (SPS), by using a method combining Design of Experiments (DOE) with physical, structural, and mechanical characterizations. The effects of SPS parameters such as temperature, pressure, dwell time, and cooling rate on the density, mechanical properties, and structure of PI were investigated. The experimental results revealed that the mechanical properties of the material were optimized by raising the sintering temperature up to 350°C. The optimized SPS processing parameters were a temperature of 350°C, a pressure of 40 MPa, and a dwell time of 5 min. Under these conditions, a relative density of 99.6% was reached within only a few minutes. The corresponding mechanical properties consisted of Young's modulus of 3.43 GPa, a Shore D hardness of 87.3, and a compressive strength of 738 MPa for a maximum compressive strain of 61.8%. Moreover, when working at 320°C and at 100 MPa, an increase in the dwell time was necessary to enhance the properties. Contrary to the other parameters, the cooling rate appeared to be a non‐significant parameter. Finally, correlations between the PI structure and the mechanical properties were made to demonstrate the densification mechanisms. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41542. 相似文献
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Sylvain Lamoine Mlissa Cumenal David A. Barriere Vanessa Pereira Mathilde Fereyrolles Laëtitia Prival Julie Barbier Ludivine Boudieu Emilie Brasset Benjamin Bertin Yoan Renaud Elisabeth Miot-Noirault Marie-Ange Civiale David Balayssac Youssef Aissouni Alain Eschalier Jrme Busserolles 《International journal of molecular sciences》2022,23(1)
18.
Cameron P. Brown Jennifer L. Boyd Antony J. Palmer Mick Phillips Charles‐Andre Couture Maxime Rivard Philippa A. Hulley Andrew J. Price Andreas Ruediger Francois Légaré Andrew J. Carr 《Advanced functional materials》2016,26(42):7662-7667
Piezoelectricity is a well‐established property of biological materials, yet its functional role has remained unclear. Here, a mechanical effect of piezoelectric domains resulting from collagen fibril organisation is demonstrated, and its role in tissue function and application to material design is described. Using a combination of scanning probe and nonlinear optical microscopy, a hierarchical structuring of piezoelectric domains in collagen‐rich tissues is observed, and their mechanical effects are explored in silico. Local electrostatic attraction and repulsion due to shear piezoelectricity in these domains modulate fibril interactions from the tens of nanometre (single fibril interactions) to the tens of micron (fibre interactions) level, analogous to modulated friction effects. The manipulation of domain size and organisation thus provides a capacity to tune energy storage, dissipation, stiffness, and damage resistance. 相似文献
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Maxime Tye-Gingras 《Numerical Heat Transfer, Part A: Applications》2013,63(4):349-366
This article presents a conceptual design of a heat sink combining a porous medium whose matrix is highly conductive and a fin. A simplified model is presented to estimate the performance of the system, relying on Darcy law and local thermal equilibrium. The objective is to minimize the hot-spot temperature under global mass constraint by using an optimization procedure based on genetic algorithms. The design variables are the porosity and material of each layer of the porous medium, the fin material, height, and width, the aspect ratio of the heat sink, and the shape of a weightless upper corner deflector which reduces the width of the inlet and outlet air slots while removing the less useful mass. Results show that the optimal porous layers were generally of copper, independent of the mass constraint. However, the fin is mostly beneficial for heavier designs, while the deflector becomes more important when lightness is required. These two special features show their efficiency by allowing a mass reduction of 95% with a decrease of only 24% in the cooling performance. 相似文献