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41.
Élise Vareilles Michel AldanondoAurélien Codet de Boisse Thierry CoudertPaul Gaborit Laurent Geneste 《Engineering Applications of Artificial Intelligence》2012,25(1):31-47
The goal of this paper is to show how it is possible to support design decisions with two different tools relying on two kinds of knowledge: case-based reasoning operating with contextual knowledge embodied in past cases and constraint filtering that operates with general knowledge formalized using constraints. Our goals are, firstly to make an overview of existing works that analyses the various ways to associate these two kinds of aiding tools essentially in a sequential way. Secondly, we propose an approach that allows us to use them simultaneously in order to assist design decisions with these two kinds of knowledge. The paper is organized as follows. In the first section, we define the goal of the paper and recall the background of case-based reasoning and constraint filtering. In the second section, the industrial problem which led us to consider these two kinds of knowledge is presented. In the third section, an overview of the various possibilities of using these two aiding decision tools in a sequential way is drawn up. In the fourth section, we propose an approach that allows us to use both aiding decision tools in a simultaneous and iterative way according to the availability of knowledge. An example dealing with helicopter maintenance illustrates our proposals. 相似文献
42.
Khaled Metwally Laurent Robert Samuel Queste Bernard Gauthier-Manuel Chantal Khan-Malek 《Microsystem Technologies》2012,18(2):199-207
Microfluidics on foil is gaining momentum due to a number of advantages of employing thin films combined with the capability
of cost-effective high-volume manufacturing of devices. In this work, ultra-thin, flexible Y-microreactors with microchannels
of 100 μm width and 30 μm depth were fabricated in thermoplastic polymer foils. The fluidic pattern was hot roll embossed
in 125 μm thick poly-methyl-methacrylate (PMMA) and 130 μm thick cyclic-olefin-copolymer (COC) films using a dry-etched microstructured
silicon wafer as a flat embossing tool in a laminator. The sealing of the channels was performed with two different techniques,
one based on lamination of SU8 dry film resist (DFR) and the other one based on spin-coated poly-dimethylsiloxane (PDMS).
Testing of the interconnected microreactor was carried out using two dye colorant solutions to demonstrate mixing. 相似文献
43.
Fothergill J.C. Montanari G.C. Stevens G.C. Laurent C. Teyssedre G. Dissado L.A. Nilsson U.H. Platbrood G. 《Dielectrics and Electrical Insulation, IEEE Transactions on》2003,10(3):514-527
The aim of the European project "ARTEMIS" is to develop a diagnostic system for assessing aging in power cable insulation. Its first task was to make a thorough characterisation of the cable insulation before aging. This is intended to provide a background against which any changes introduced by thermo-electric aging can be identified. The aging markers derived from this initial characterisation will be considered both as diagnostic indicators in their own right, and also to develop an aging model for predictive purposes, if and when possible. This stage of the ARTEMIS programme is now complete and we will present an analysis of the results, and show how they may be correlated with the concepts proposed in aging theories. 相似文献
44.
This paper reports on the creation of interactive computer installations that combine artificial life and real life by means
of human-computer interactions. These installations have focused on real-time interactions and evolutionary image processes.
Accordingly, visitors to the installations become essential parts of the systems by transmitting their individual behaviors,
emotions, and personalities to the image processes of the work. Images in these installations are no longer static, pre-fixed,
and predictable, but become “living systems” themselves, representing minute changes in the viewers' interactions with the
evolutionary image processes. Natural evolution has brought about a vast variety of forms and structures in nature. This research
considers how artificial evoluation can function as a tool of the visual creation process; design should no longer be done
by a designer or artist, but should emerge through the evolutionary image process itself. 相似文献
45.
The operational levels of production management, often called production activity control (PAC) or manufacturing process control, require increasing reaction capabilities in order to adapt the workshop management to the changes of its environment. It often implies giving more responsibilities to the low decision levels. However, the management of the corresponding degrees of freedom is generally unusual. In such a situation, decision support systems (DSSs) provide a way to reconcile the satisfaction of mid-level objectives and the reaction requirements. A conceptual model is described that provides a design framework for a PAC DSS. Since the available knowledge lies mainly in expertise, a DSS has been implemented using a knowledge-based system. The uncertainty and imprecision of the managed information led to the use of fuzzy logic as a modeling tool. Moreover, various inference semantics have been implemented in the expert rules because different kinds of reasoning have been identified. Two versions of the DSS are described and several examples of implemented reasoning processes are developed. 相似文献
46.
Griseri V. Fukunaga K. Maeno T. Laurent C. Levy L. Payan D. 《Dielectrics and Electrical Insulation, IEEE Transactions on》2004,11(5):891-898
Dielectric materials are frequently used in satellite structures for substantial savings in weight. Their dielectric nature and the effect of different forms of radiation encountered in space combine to accumulate electrical charges resulting in the occurrence of electrostatic discharges which cause harmful interference with the electronic parts of the satellite, leading to its malfunction or to a total loss of equipment control. Therefore, the behavior of dielectrics under irradiation must be investigated before being used in space. A pulsed electroacoustic (PEA) device was mounted in an irradiation chamber to monitor the spatial distribution of electrons implanted into polymer films during electronic irradiation. Internal charge accumulation was clearly identified. Penetration depth versus energy was double checked by comparing PEA with surface potential data. 相似文献
47.
Sébastien Hentz Laurent Daudeville Frédéric V. Donzé 《Canadian Metallurgical Quarterly》2004,130(6):709-719
The use of a three-dimensional discrete element method (DEM) is proposed to study concrete structures submitted to dynamic loading. The aim of this paper is to validate the model first in the quasistatic domain, and second in dynamic compression, at the sample scale. A particular growing technique is used to set a densely packed assembly of arbitrarily sized spherical particles interacting together, representing concrete. An important difference from classical DEMs where only contact interactions are considered, is the use of an interaction range. First, the correct identification of parameters of the DEM model to simulate elastic and nonlinear deformation including damage and rupture is made through quasistatic uniaxial compression and tension tests. The influence of the packing is shown. The model produces a quantitative match of strength and deformation characteristics of concrete in terms of Young’s modulus, Poisson’s coefficient, and compressive and tensile strengths. Then, its validity is extended through dynamic tests. The simulations exhibit complex macroscopic behaviors of concrete, such as strain softening, fractures that arise from extensive microcracking throughout the assembly, and strain rate dependency. 相似文献
48.
Laurent Jeff; Catanzaro Salvatore J.; Joiner Thomas E. Jr. 《Canadian Metallurgical Quarterly》2004,16(4):373
Considerable empirical support exists for the positive affect and negative affect components of the tripartite model of anxiety and depression proposed by L. A. Clark and D. Watson (1991); however, less attention has been paid to the physiological hyperarousal component of the model. The development of the Physiological Hyperarousal Scale for Children (PH-C; J. Laurent, S. J. Catanzaro, & T. E. Joiner Jr., 1995) is described. The psychometric properties of items are examined using students in Grades 6-12 (N = 398). Initial scale validation includes a joint factor analysis with the Positive and Negative Affect Scale for Children (PANAS-C; J. Laurent et al., 1999; J. Laurent, K. Potter, & S. J. Catanzaro, 1994). The relationship between the PH-C and existing measures that tap related constructs is examined. Together, the PH-C and PANAS-C provide a means to assess tripartite model constructs useful in differentiating anxiety and depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
49.
Marc Rennhard Sandro Rafaeli Laurent Mathy Bernhard Plattner David Hutchison 《Electronic Commerce Research》2004,4(1-2):83-111
The lack of privacy is one of the main reasons that limits trust in e-commerce. Current e-commerce practice enforces a customer to disclose her identity to the e-shop and the use of credit cards makes it straightforward for an e-shop to know the real identity of its customers. Although there are some payment systems based on untraceable tokens, they are not as widely used as credit cards. Furthermore, even without buying anything, a customer is already disclosing some information about who or where she may be by just connecting to the e-shop's web server and leaving behind an IP-address. In this paper, we present novel components that enable secure pseudonymous e-commerce. On the one hand, these components allow a customer to browse through an e-shop, select goods, and pay the goods with her credit card such that neither the e-shop operator nor the credit card issuer nor an eavesdropper is able to get any information about the customer's identity. On the other hand, it is guaranteed that none of the involved parties is able to act dishonestly during the credit card payment. Such a system could greatly enhance trust in e-commerce since it overcomes the customers' privacy concerns. 相似文献
50.
Xavier Desforges Abdallah Habbadi Laurent Geneste François Soler 《Journal of Intelligent Manufacturing》2004,15(1):39-53
The study of smart sensors and actuators led, during the past few years, to the development of facilities which improve traditional sensors and actuators in a necessary way to automate production systems. In another context, many studies have been carried out aimed at defining a decisional structure for production activity control and the increasing need of reactivity leads to the autonomization of decisional levels close to the operational system. We study in this paper the natural convergence between these two approaches and we propose an integration architecture, dealing with machine tool and machining control, that enables the exploitation of distributed smart sensors and actuators in the decisional system. 相似文献