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Javier Pliego‐Jimenez Marco Arteaga‐Perez 《International Journal of Adaptive Control and Signal Processing》2017,31(8):1217-1231
In this work, we consider the problem of 2 robots handling a rigid object, while model‐parameter uncertainties are assumed. It is also assumed that the manipulators can push but not pull the object. Several control schemes proposed in the literature attempt to control the position of the object rather than its orientation. However, many industrial tasks require to move and to rotate the object. To this end, we propose an adaptive hybrid position/force control law based on time‐variant holonomic constraints, which allow for object position and orientation control. Our approach guarantees that the force error asymptotically converges to 0; therefore, a stable grasp can be accomplished by means of a proper definition of the desired pushing force. In addition, a dynamic model of the cooperative system based on the load distribution and joint‐space orthogonalization principles is developed. Experimental results are presented to validate the proposed dynamic model and control scheme. 相似文献
95.
Lipolysis,lipid peroxidation and texture of Serrano ham processed under different ripening temperature conditions 下载免费PDF全文
Ana del Olmo Javier Calzada Manuel Nuñez 《International Journal of Food Science & Technology》2016,51(8):1793-1800
Lipolysis, lipid peroxidation, texture and rancid taste were investigated in Serrano hams processed under low, medium and high ripening temperature conditions (RTC) for 15 months. Medium RTC hams showed the highest contents of saturated and monounsaturated free fatty acids (FFAs) from month 5 to 15 and of polyunsaturated FFAs from month 7 to 12. The primary peroxidation index decreased during ripening in all hams, with higher levels for low RTC hams from month 5 onwards. Contrarily, the secondary peroxidation index increased during ripening in all hams, with higher levels for medium RTC hams from month 7 onwards. Texture parameters varied significantly among ham muscles. Shear force increased during ripening in all hams, with higher values for medium RTC hams, whereas cutting force was not influenced by RTC or ripening time. Rancid taste scarcely developed during ripening and was not affected by RTC. 相似文献
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Tomáš Brázdil Javier Esparza Stefan Kiefer Antonín Kučera 《Formal Methods in System Design》2013,43(2):124-163
The paper gives a summary of the existing results about algorithmic analysis of probabilistic pushdown automata and their subclasses. 相似文献
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Javier Solano Martínez Jérôme Mulot Fabien Harel Daniel Hissel Marie-Cécile Péra Robert I. John Michel Amiet 《Engineering Applications of Artificial Intelligence》2013,26(7):1772-1779
The aim of this paper is to present experimental validation results of an energy management system for hybrid electrical vehicles based on type-2 fuzzy logic. The energy management system (EMS) is designed by extracting knowledge from several experts using surveys. The consideration of interval type-2 fuzzy sets enables modeling the uncertainty in the answers of the experts. The validation of the EMS is performed on a real-scale heavy duty vehicle equipped with different energy sources such as batteries, fuel cell system and ultracapacitors. Experimental results are strong evidence that type-2 fuzzy logic is wide adapted for performing the energy management in hybrid electrical vehicles. 相似文献
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Fermín L. Cruz José A. Troyano Fernando Enríquez F. Javier Ortega Carlos G. Vallejo 《Expert systems with applications》2013,40(8):3174-3184
Nowadays, people do not only navigate the web, but they also contribute contents to the Internet. Among other things, they write their thoughts and opinions in review sites, forums, social networks, blogs and other websites. These opinions constitute a valuable resource for businesses, governments and consumers. In the last years, some researchers have proposed opinion extraction systems, mostly domain-independent ones, to automatically extract structured representations of opinions contained in those texts. In this work, we tackle this task in a domain-oriented approach, defining a set of domain-specific resources which capture valuable knowledge about how people express opinions on a given domain. These resources are automatically induced from a set of annotated documents. Some experiments were carried out on three different domains (user-generated reviews of headphones, hotels and cars), comparing our approach to other state-of-the-art, domain-independent techniques. The results confirm the importance of the domain in order to build accurate opinion extraction systems. Some experiments on the influence of the dataset size and an example of aggregation and visualization of the extracted opinions are also shown. 相似文献
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Manuel Bethencourt Francisco Javier Botana María José Cano Leandro González-Rovira Mariano Marcos José María Sánchez-Amaya 《Metallurgical and Materials Transactions A》2012,43(1):182-194
A wide variety of anticorrosive treatments for aluminum alloys that can be employed as “green” alternatives to those based
on Cr(VI) are currently under development. This article reports a study of the morphological and anticorrosive characteristics
of surface layers formed on the Al–Cu alloy AA2017 by immersion treatment in baths of cerium salt, accelerated by increased
temperature and the employment of hydrogen peroxide. Scanning electron microscopy (SEM)/X-ray energy dispersive spectroscopy
(XEDS) studies of the samples treated have demonstrated the existence of a heterogeneous layer formed by a film of aluminum
oxide/hydroxide on the matrix, and a series of dispersed islands of cerium over the cathodic intermetallics. The protective
efficacy has been evaluated using electrochemical techniques, linear polarizations (LP) and electrochemical impedance spectroscopy
(EIS), and salt spray tests. The results obtained indicate that the layer provided good resistance to corrosion in media with
chlorides, and the method gives a considerable reduction of the time required for the immersion treatments. 相似文献