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991.
Rocío de Andrés José Luis García-Lapresta Luis Martínez 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2010,14(1):21-34
The performance appraisal is a relevant process to keep and improve the competitiveness of companies in nowadays. In spite
of this relevance, the current performance appraisal models are not sufficiently well-defined either designed for the evaluation
framework in which they are defined. This paper proposes a performance appraisal model where the assessments are modelled
by means of linguistic information provided by different sets of reviewers in order to manage the uncertainty and subjectivity
of such assessments. Therefore, the reviewers could express their assessments in different linguistic scales according to
their knowledge about the evaluated employees, defining a multi-granular linguistic evaluation framework. Additionally, the
proposed model will manage the multi-granular linguistic labels provided by appraisers in order to compute collective assessments
about the employees that will be used by the management team to make the final decision about them. 相似文献
992.
993.
Stéphane Zieba Philippe Polet Frédéric Vanderhaegen Serge Debernard 《Cognition, Technology & Work》2010,12(3):193-203
Unmanned ground vehicles tend to be more and more autonomous, but both complete teleoperation and full autonomy are not efficient
enough to deal with all possible situations. To be efficient, the human–robot system must be able to anticipate, react and
recover from errors of different kinds, i.e., to be resilient. From this observation, this paper proposes a survey on the
resilience of a human–machine system and the means to control the resilience. The resilience of a system can be defined as
the ability to maintain or recover a stable state when subject to disturbance. Adjustable autonomy and human–machine cooperation
are considered as means of resilience for the system. This paper then proposes three indicators to assess different meanings
of resilience of the system: foresight and avoidance of events, reaction to events and recovery from occurrence of events.
The third of these metrics takes into consideration the concept of affordances that allows a common representation for the
opportunities of action between the automated system and its environment. 相似文献
994.
Roberto Sanchez Geneviève Dauphin-Tanguy Xavier Guillaud Frédéric Colas 《Simulation Modelling Practice and Theory》2010,18(9):1185-1198
This paper proposes a model of a three phase electrical inverter with a LC output filter in delta connection used in a renewable energy supply system. The concept of inverse bond graph via bicausality is used for the control law design. The control law robustness is tested by connecting passive and active (induction machine) loads. 相似文献
995.
Adrià Junyent-Ferré Oriol Gomis-Bellmunt Andreas Sumper Marc Sala Montserrat Mata 《Simulation Modelling Practice and Theory》2010,18(9):1365-1381
The present paper deals with the modeling of wind turbine generation systems. The model of a doubly fed induction generator, along with the corresponding converter, crow bar protection and electrical grid is described. The different level control strategies both in normal operation and under voltage dig conditions are discussed, including speed control, torque and reactive power control for the rotor-side converter, reactive and DC voltage control for the grid-side converter and the corresponding current loops control. The results obtained with simulations are compared to experimental data obtained from voltage sags provoked to real wind turbines. 相似文献
996.
997.
The automatic compilation of bilingual lists of terms from specialized comparable corpora using lexical alignment has been successful for single-word terms (SWTs), but remains disappointing for multi-word terms (MWTs). The low frequency and the variability of the syntactic structures of MWTs in the source and the target languages are the main reported problems. This paper defines a general framework dedicated to the lexical alignment of MWTs from comparable corpora that includes a compositional translation process and the standard lexical context analysis. The compositional method which is based on the translation of lexical items being restrictive, we introduce an extended compositional method that bridges the gap between MWTs of different syntactic structures through morphological links. We experimented with the two compositional methods for the French–Japanese alignment task. The results show a significant improvement for the translation of MWTs and advocate further morphological analysis in lexical alignment. 相似文献
998.
Liquid recirculation in microfluidic channels by the interplay of capillary and centrifugal forces 总被引:1,自引:1,他引:0
Jose L. Garcia-Cordero Lourdes Basabe-Desmonts Jens Ducrée Antonio J. Ricco 《Microfluidics and nanofluidics》2010,9(4-5):695-703
We demonstrate a technique to recirculate liquids in a microfluidic channel by alternating predominance of centrifugal and capillary forces to rapidly bring the entire volume of a liquid sample to within one diffusion length, δ, of the surface, even for sample volumes hundreds of times the product of δ and the geometric device area. This is accomplished by repetitive, random sampling of an on-disc sample reservoir to form a thin fluid layer of thickness δ in a microchannel, maintaining contact for the diffusion time, then rapidly exchanging the fluid layer for a fresh aliquot by disc rotation and stoppage. With this technique, liquid volumes of microlitres to millilitres can be handled in many sizes of microfluidic channels, provided the channel wall with greatest surface area is hydrophilic. We present a theoretical model describing the balance of centrifugal and capillary forces in the device and validate the model experimentally. 相似文献
999.
Martijn H. A. Bonte Lionel Fourment Tien-tho Do A. H. van den Boogaard J. Huétink 《Structural and Multidisciplinary Optimization》2010,42(5):797-810
During the last decades, simulation software based on the Finite Element Method (FEM) has significantly contributed to the
design of feasible forming processes. Coupling FEM to mathematical optimization algorithms offers a promising opportunity
to design optimal metal forming processes rather than just feasible ones. In this paper Sequential Approximate Optimization (SAO) for optimizing forging processes is discussed. The algorithm
incorporates time-consuming nonlinear FEM simulations. Three variants of the SAO algorithm—which differ by their sequential
improvement strategies—have been investigated and compared to other optimization algorithms by application to two forging
processes. The other algorithms taken into account are two iterative algorithms (BFGS and SCPIP) and a Metamodel Assisted
Evolutionary Strategy (MAES). It is essential for sequential approximate optimization algorithms to implement an improvement
strategy that uses as much information obtained during previous iterations as possible. If such a sequential improvement strategy
is used, SAO provides a very efficient algorithm to optimize forging processes using time-consuming FEM simulations. 相似文献
1000.
Pierre De Loor Romain Bénard Pierre Chevaillier 《Expert systems with applications》2011,38(5):5145-5153
The aim of this paper is to present the principles and results about case-based reasoning adapted to real-time interactive simulations, more precisely concerning retrieval mechanisms. The article begins by introducing the constraints involved in interactive multiagent-based simulations. The second section presents a framework stemming from case-based reasoning by autonomous agents. Each agent uses a case base of local situations and, from this base, it can choose an action in order to interact with other autonomous agents or users’ avatars. We illustrate this framework with an example dedicated to the study of dynamic situations in football. We then go on to address the difficulties of conducting such simulations in real-time and propose a model for case and for case base. Using generic agents and adequate case base structure associated with a dedicated recall algorithm, we improve retrieval performance under time pressure compared to classic CBR techniques. We present some results relating to the performance of this solution. The article concludes by outlining future development of our project. 相似文献