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101.
Andrés Vignaga Frédéric Jouault María Cecilia Bastarrica Hugo Brunelière 《Software and Systems Modeling》2013,12(1):105-119
Model management is essential for coping with the complexity introduced by the increasing number and varied nature of artifacts involved in model-driven engineering-based projects. Global model management (GMM) addresses this issue by enabling the representation of artifacts, particularly transformation composition and execution, within a model called a megamodel. Type information about artifacts can be used for preventing type errors during execution. Built on our previous work, in this paper we present the core elements of a type system for GMM that improves its original typing approach and enables both typechecking and type inference on artifacts within a megamodel. This type system is able to deal with non-trivial situations such as the use of higher order transformations. We also present a prototypical implementation of such a type system. 相似文献
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Olivier Quéméner Frédéric Joly Alain Neveu 《International Journal of Heat and Mass Transfer》2012,55(4):1197-1207
In this paper, we propose an extension of the amalgam method to reduce advection diffusion problem with time dependent parameters. From a full general basis, this technique consists to select rapidly the most influent modes, and to add to them the remaining modes balanced by a coefficient. The originality of this paper lies in the fast obtention of a full degraded model, used as a reference in a minimization process of the reduced model’s error. Transcribed to the physical space, this error approaches the error between the reduced model and the real physical finite elements model. The treated application is a disk rotating at a variable velocity with time dependent thermal inputs. Comparison between the reduced and the finite elements model gives a gain in term of computational time of 36 for a mean error on the entire domain equal to 0.42%. 相似文献
105.
Chatterjee Gaurav Latorre Laurent Mailly Frédérick Nouet Pascal Hachelef Nacim Oudea Coumar 《Microsystem Technologies》2017,23(9):3969-3978
Microsystem Technologies - Inertial measurement units (IMU) are essentially a combination of acceleration and rotation rate sensors, generating position and attitude information. For tactical and... 相似文献
106.
WANG Jiang FAUTRELLE Yves REN Zhong-ming LI Xi NGUYEN-THI Henri MANGELINCK-NOEL Nathalie SALLOUM ABOU JAOUDE Georges ZHONG Yun-bo KALDRE Imants BOJAREVICS Andris BULIGINS Leonid 《钢铁研究学报(英文版)》2012,(Z1):381-385
Sn-3wt%Pb alloy was directionally solidified without and with a 0.08T transverse magnetic field(TMF),and real-time recorded by in-situ synchrotron X-ray imaging.Results indicate that TMF shortened the distance from the location of nucleation to the advancing interface,and accelerated the growth rate of the equiaxed crystal,which caused the columnar-to-equiaxed transition(CET)finally.The thermoelectromagnetic convection(TEMC)in front of the interface and around the crystal’s dendritic branch should respond to changes of the distance and the growth rate. 相似文献
107.
Influence of high power ultrasound on physical–chemical properties of polypropylene films aimed for food packaging: barrier and contact angle features 下载免费PDF全文
Mario Ščetar Mia Kurek Anet Režek Jambrak Frédéric Debeaufort Kata Galić 《Polymer International》2017,66(11):1572-1578
Investigation was focused on the impact of high power ultrasound (HPUS), also called thermosonication, on the oxygen permeation properties (permeability, solubility and diffusion coefficients) of barrier films aimed for food packaging. For this purpose, biaxially oriented polypropylene (BOPP) coated with acrylic/polyvinylidene chloride (BOPPAcPVDC) and biaxially oriented coextruded polypropylene (BOPPcoex) were used. The physical–chemical profile of the samples was determined using goniometry. There is a significant impact only of extreme HPUS conditions (the longest time and the highest amplitude) on the permeability, solubility and diffusion coefficients of oxygen through the BOPP films. The highest influence on the oxygen permeability in both investigated BOPP samples involved an HPUS with an amplitude of 100% during a 6 min treatment. However, BOPP samples showed different sensitivities at lower HPUS treatments. © 2017 Society of Chemical Industry 相似文献
108.
Leyla Belkaïd 《Costume》2014,48(1):60-81
This essay describes the evolution of the garment known as a blusa, worn by urban women in north-western Algeria. The blusa, a full-length dress with short sleeves, was conceived and developed in the cities of Tlemcen and Oran. It incorporates locally meaningful traditions as well as fashion styles in conjunction with different cultures. Its transformation illustrates how Algerian women resisted cultural assimilation through dress while creatively appropriating western European textiles, techniques and aesthetics in their clothing, during the French colonial period (1830–1962) and its aftermath. The exploration of the contemporary blusa variations reveals how the relationship between clothing and identity is still highly complex in Algerian cities. To date, the invention, the rituals, the design, and the production of the blusa dress has been little studied. This paper reconstitutes an historical puzzle based on recent object-based research and anthropological investigations. It seeks to interpret the blusa as an interface between tradition and modernity. 相似文献
109.
Guglielmo Barone Antonello d’Alessandro Guido de Blasio 《Papers in Regional Science》2019,98(5):1893-1902
National policies may have heterogeneous effects at the regional level. When coming to programmes aimed at increasing human capital, worker mobility from poorer to richer regions can reduce the benefits of the policy for the former areas. We focus on Italy and estimate the impact of education on the probability of migrating from a lagging area to a leading one. Endogeneity is addressed by exploiting an increase in the minimum school-leaving age in an instrumental variable framework. We find that one additional year of education increases the probability to migrate by 1.7 percentage points (9% of the average migration rate). 相似文献
110.
Kurtulus Kullu Uğur Güdükbay Dinesh Manocha 《Autonomous Agents and Multi-Agent Systems》2017,31(6):1403-1423
Behavioral plausibility is one of the major aims of crowd simulation research. We present a novel approach that simulates communication between the agents and assess its influence on overall crowd behavior. Our formulation uses a communication model that tends to simulate human-like communication capability. The underlying formulation is based on a message structure that corresponds to a simplified version of Foundation for Intelligent Physical Agents Agent Communication Language Message Structure Specification. Our algorithm distinguishes between low- and high-level communication tasks so that ACMICS can be easily extended and employed in new simulation scenarios. We highlight the performance of our communication model on different crowd simulation scenarios. We also extend our approach to model evacuation behavior in unknown environments. Overall, our communication model has a small runtime overhead and can be used for interactive simulation with tens or hundreds of agents. 相似文献