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141.
C. Thanga Raj Radha Thangaraj Millie Pant Pascal Bouvry Ajith Abraham 《Applied Artificial Intelligence》2013,27(9):809-831
This article deals with the design optimization of a squirrel-cage three-phase induction motor, selected as the driving power of spinning machines in the textile industry, using three newly developed versions of differential evolution (DE) algorithms called modified DE versions (CMDE, GMDE, and LMDE). Efficiency, which decides the operating or running cost of the motor (industry), is considered as the objective function. First, the algorithms are applied to design a general purpose motor with seven variables and nine performance-related parameters with their nominal values as constraints. To make the machine feasible, practically acceptable to serve in textile industries, and less costly to operate, certain constraints are modified in accordance with the demands of the spinning application. Comparison of the optimum designs with the industrial (existing) motor reveals that the motor designed by the proposed algorithms consumes less power input. 相似文献
142.
Vincent Wawrzyniak Hervé Piégay Pascal Allemand Lise Vaudor Philippe Grandjean 《International journal of remote sensing》2013,34(13):4812-4831
Braided rivers exhibit high spatial thermal heterogeneity that is difficult to understand using only in situ measurements. In this summer study, we used a drone and a powered paraglider to acquire very high spatial resolution (14–27 cm) thermal infrared (TIR) images of nine braided reaches located in the French Alps. We applied atmospheric corrections to TIR images and calibrated them based on in situ data. To characterize spatial and temporal thermal patterns, three temporal approaches were applied. A single survey of each site was performed to comparatively explore the nine braided reaches. Three reaches were imaged twice, in 2010 and 2011, to explore inter-annual variability. Finally, two reaches were selected for an intra-day survey for which four and three flights, respectively, were realized within one day. We reported two types of thermal patterns in braided reaches, the first showing very low thermal variability throughout the day. This low variability was linked to the low diversity found in the aquatic habitat, notably due to proglacial regimes with high summer flows which homogenize water temperatures. The second type exhibited a higher thermal variability with changes during the day. The temperature of flowing channels changed during the daytime according to air temperature. In contrast, the temperature of channels downstream connected to the main network exhibited smaller changes, which created thermal variability over space and time associated with hyporheic or phreatic flows. Non-proglacial and proglacial reaches behaved differently according to air temperature. Proglacial reaches were colder and less sensitive to air temperature in comparison with non-proglacial reaches. These findings allow for a prediction of habitat diversity from temperature heterogeneity based on time and the proportion of ponds, alluvial, and groundwater channels. 相似文献
143.
Pascal Gautron Cyril Delalandre Jean‐Eudes Marvie Pascal Lecocq 《Computer Graphics Forum》2013,32(7):305-314
We introduce Boundary‐Aware Extinction Maps for interactive rendering of massive heterogeneous volumetric datasets. Our approach is based on the projection of the extinction along light rays into a boundary‐aware function space, focusing on the most relevant sections of the light paths. This technique also provides an alternative representation of the set of participating media, allowing scattering simulation methods to be applied on arbitrary volume representations. Combined with a simple out‐of‐core rendering framework, Boundary‐Aware Extinction Maps are valuable tools for interactive applications as well as production previsualization and rendering. 相似文献
144.
145.
Pascal Tournier 《电子设计技术》2005,12(12):74-74,115
手机等便携式电子产品正集成越来越多的多媒体功能,这引起了人们对增加立体声功能的极大兴趣。单声道结构用于声音放大及和弦铃声,在某些情况下可用作免提扬声器。虽然功能已足够,但这并非是令人满意的高质量音乐播放解决方案。 相似文献
146.
Edwina Klay Frédéric Diologent Johanne Arnéodo Pascal Dubos Andreas Mortensen 《Intermetallics》2011,19(5):726-737
Seven alloys of the ternary Au-Cu-Pt system, containing 75 or 76.5 wt.% Au with 0–15 wt.% Pt and heat-treated to a fully ordered condition, are examined using in-situ synchrotron radiation to determine transformation temperatures and phases formed, and to investigate mechanisms of ordering and disordering. These experiments are complemented by differential scanning calorimetry. Diffraction data show that the alloys can be separated into three groups according to their stable low-temperature ordered phase(s), namely L10, L12, or the two combined. Platinum increases transformation temperatures in comparison with binary AuCu, two-phase ordered alloys showing the highest transformation temperatures. Details of the evolution of the X-ray diffraction peak structures upon heating and cooling point to significant differences between mechanisms of disordering and ordering: whereas ordering visibly proceeds at significant undercooling by nucleation and growth, disordering appears, from the visible shifts in peak position, to progress in more homogeneous fashion within the alloy. 相似文献
147.
148.
Visualization is often invaluable to understand the behavior of optimization algorithms, identify their bottlenecks or pathological
behaviors, and suggest remedial techniques. Yet developing visualizations is often a tedious activity requiring significant
time and expertise. This paper presents a framework for the visualization of constraint-based local search (CBLS) algorithms.
Given a high-level model and a declarative visualization specification, the CBLS visualizer systematically produces animations
to visualize constraints and objectives, violations, and conflicts, as well as the temporal behavior of these measures. The
visualization specification is declarative and typically composed of a triple (what,where,how) indicating what to display, where, and with which graphical objects. The visualizer architecture is compositional and extensible.
It provides building blocks which can be assembled freely by the user and focuses almost exclusively on static aspects, the
dynamic aspects being automated by the use of invariants. The paper highlights various functionalities of the visualizer and
describes a blueprint for its implementation. 相似文献
149.
Michaël Ndjinga Anela Kumbaro Pascal Laurent-Gengoux 《Nuclear Engineering and Design》2008,238(8):2075-2083
The application of the generalized Roe scheme to the numerical simulation of two-phase flow models requires a fast and robust computation of the absolute value of the system matrix. In several models such as the two-fluid model or a general multifield model, this matrix has a non-trivial eigenstructure and the eigendecomposition is often ill conditioned. We give a general algorithm avoiding the diagonalization process. It is based on an iterative approach, but turns out to be an exact computation when the eigenvalues are real. The knowledge of the characteristic polynomial gives us an easy access to the eigenvalues but however, the iterative scheme can be used with only estimates of the eigenvalues, using for example Gershgorin’s disk localization. We finally show some numerical results of two-fluid model simulations involving interfacial pressure and a virtual mass force model. 相似文献
150.
Lapointe Nicolas P.; Ung Roth-Visal; Rouleau Pascal; Guertin Pierre A. 《Canadian Metallurgical Quarterly》2008,122(3):576
Experiments in completely spinal cord transected (Tx) cats have provided compelling evidence that clonidine combined with tail stimulation can promote locomotor function recovery. However, clonidine has generally failed to induce locomotor activity in other comparable animal models suggesting the existence of species- or condition-specific effects. This study aimed at investigating the effects of clonidine administered (0.25 or 5.0 mg/kg, i.p.) in mice during tail pinching in early (6-7 days post-Tx) or late (41-42 days post-Tx) paraplegic animals (Th9/10 level). Comparisons were made with the effects induced by 8-OH-DPAT (1.0 mg/kg, i.p.), a 5-HT1A/7 receptor agonist known to display prolocomotor effects. Clonidine with or without tail pinching failed to induce hind limb movements and even suppressed the frequency of spontaneously occurring nonlocomotor (NLM) and locomotor-like movements (LM) whereas tail pinching alone (prior to clonidine administration) increased the frequency of spontaneous movements specifically in late chronic animals. In turn, 8-OH-DPAT clearly induced hind limb movements that remained relatively unchanged during tail pinching. Altogether, the results suggest that the prolocomotor effects of clonidine reported elsewhere must depend upon stimuli or factors that remain to be identified. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献