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71.
Gustavo Olague Cynthia B. Pérez Francisco Fernández Evelyne Lutton 《Artificial Life and Robotics》2009,13(2):585-596
This article presents an adaptive approach to improving the infection algorithm that we have used to solve the dense stereo
matching problem. The algorithm presented here incorporates two different epidemic automata along a single execution of the
infection algorithm. The new algorithm attempts to provide a general behavior of guessing the best correspondence between
a pair of images. Our aim is to provide a new strategy inspired by evolutionary computation, which combines the behaviors
of both automata into a single correspondence problem. The new algorithm will decide which automata will be used based on
the transmission of information and mutation, as well as the attributes, texture, and geometry, of the input images. This
article gives details about how the rules used in the infection algorithm are coded. Finally, we show experiments with a real
stereo pair, as well as with a standard test bed, to show how the infection algorithm works. 相似文献
72.
M Fernández J Cao MD Vázquez-Illanes JI Ramos-Martínez JA Villamarín 《Canadian Metallurgical Quarterly》1994,33(2):355-363
Phosphofructokinase purified from mantle tissue of the sea mussel Mytilus galloprovincialis, was phosphorylated "in vitro" by the catalytic subunit of cyclic AMP-dependent protein kinase. The incorporation of phosphate gave rise to an activation of the enzyme by increasing its affinity for fructose-6-phosphate, by decreasing its sensitivity to the inhibition by ATP and by enhancing the effect of allosteric activators (5'-AMP and fructose-2,6-bisphosphate). In addition, the effects of phosphorylation on the catalytic activity are pH-dependent. 相似文献
73.
Rodríguez J Fernández S Palacios SL Crespo RD Fernández JM Guinea A Virgós JM Olivares J 《Applied optics》1995,34(27):6172-6179
We present a theoretical method that makes it possible to analyze three-dimensional (3-D) integrated optical waveguides with arbitrary refractive-index profiles. With this method it is easy to obtain effective indexes, propagation constants, and coupling-switching properties of planar and channel optical waveguides. This theoretical approach involves one's modeling the original optical waveguide by means of an equivalent optical waveguide whose effective index is evaluated by the application of a technique that we call the asymptotic effective-index method. The numerical values show good convergence and accuracy for effective indexes, propagation constants, and coupling-switching characteristics. Theoretical and experimental results are given. 相似文献
74.
Criticality Analysis for Maintenance Purposes: A Study for Complex In‐service Engineering Assets
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Adolfo Crespo Márquez Pedro Moreu de León Antonio Sola Rosique Juan F. Gómez Fernández 《Quality and Reliability Engineering International》2016,32(2):519-533
The purpose of this paper is to establish a basis for a criticality analysis, considered here as a prerequisite, a first required step to review the current maintenance programs, of complex in‐service engineering assets. Review is understood as a reality check, a testing of whether the current maintenance activities are well aligned to actual business objectives and needs. This paper describes an efficient and rational working process and a model resulting in a hierarchy of assets, based on risk analysis and cost–benefit principles, which will be ranked according to their importance for the business to meet specific goals. Starting from a multicriteria analysis, the proposed model converts relevant criteria impacting equipment criticality into a single score presenting the criticality level. Although detailed implementation of techniques like Root Cause Failure Analysis and Reliability Centered Maintenance will be recommended for further optimization of the maintenance activities, the reasons why criticality analysis deserves the attention of engineers and maintenance and reliability managers are precisely explained here. A case study is presented to help the reader understand the process and to operationalize the model. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
75.
Mónica Giménez‐Marqués Elena Bellido Thomas Berthelot Teresa Simón‐Yarza Tania Hidalgo Rosana Simón‐Vázquez África González‐Fernández José Avila Maria Carmen Asensio Ruxandra Gref Patrick Couvreur Christian Serre Patricia Horcajada 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(40)
Controlling the outer surface of nanometric metal–organic frameworks (nanoMOFs) and further understanding the in vivo effect of the coated material are crucial for the convenient biomedical applications of MOFs. However, in most studies, the surface modification protocol is often associated with significant toxicity and/or lack of selectivity. As an alternative, how the highly selective and general grafting GraftFast method leads, through a green and simple process, to the successful attachment of multifunctional biopolymers (polyethylene glycol (PEG) and hyaluronic acid) on the external surface of nanoMOFs is reported. In particular, effectively PEGylated iron trimesate MIL‐100(Fe) nanoparticles (NPs) exhibit suitable grafting stability and superior chemical and colloidal stability in different biofluids, while conserving full porosity and allowing the adsorption of bioactive molecules (cosmetic and antitumor agents). Furthermore, the nature of the MOF–PEG interaction is deeply investigated using high‐resolution soft X‐ray spectroscopy. Finally, a cell penetration study using the radio‐labeled antitumor agent gemcitabine monophosphate (3H‐GMP)‐loaded MIL‐100(Fe)@PEG NPs shows reduced macrophage phagocytosis, confirming a significant in vitro PEG furtiveness. 相似文献
76.
BM Fernández 《Canadian Metallurgical Quarterly》1996,7(2):48-54
Being part of the first report of the SEEIUC Forum on the training of nurses in critical care units, this article shows the different postgraduation training paths which Spanish legislation establishes. The "Titulos Oficiales de Especialización Profesional" ("Official Degrees on Professional Specialization") settle the seven nursing specialties regulated by the Decreto 992/1987. Following a second path, "Titulos de Postgraduado no Oficiales" ("Non-official postgraduation degrees"), every University acknowledged by the LRU and creating them as their Own Degrees, may organize Master courses, University experts, University specialists and Postgraduation university degrees, according to their autonomy. So that this autonomous offer is as homogeneous as possible, there is an interuniversity agreement which encompasses 24 national universities and gathers the general criteria for the academic organization of such courses. The report is completed by an analysis of the training offer for critical care nursing, developed during the 1995/1996 course in Spain. 相似文献
77.
D Defey E Storch S Cardozo O Díaz G Fernández 《Canadian Metallurgical Quarterly》1996,42(10):1447-1456
Menopause has often been described as a time of loss and decay in the lay and medical literature. The present research aims at defining women's perception of themselves and their health care needs in this period of life. Through a community-based sample of women, participative assessments were performed and their conclusions contrasted with the opinions of male and female gynecologists. Though both groups coincided concerning the relevance of loneliness, partnership, beauty and the "empty nest" syndrome, several items showed a marked difference between both groups. Gynecologists tended to perceive women as much more striving for an active sex-life, depressed, lacking projects for the future and worried about their health care than they actually were. Women, instead, stressed the relevance of menopause as a life crisis laden with opportunities for self-accomplishment and positive changes in life-style towards greater autonomy. 相似文献
78.
Nominal terms generalise first-order terms by including abstraction and name swapping constructs. α-equivalence can be easily axiomatised using name swappings and a freshness relation, which makes the nominal approach well adapted to the specification of systems that involve binders. Nominal matching is matching modulo α-equivalence and has applications in programming languages, rewriting, and theorem proving. In this paper, we describe efficient algorithms to check the validity of equations involving binders and to solve matching problems modulo α-equivalence, using the nominal approach. 相似文献
79.
Javier Sánchez-Monedero Pedro A. Gutiérrez F. Fernández-Navarro C. Hervás-Martínez 《Neural Processing Letters》2011,34(2):101-116
Recently, a multi-objective Sensitivity–Accuracy based methodology has been proposed for building classifiers for multi-class problems. This technique is especially suitable for imbalanced and multi-class datasets. Moreover, the high computational cost of multi-objective approaches is well known so more efficient alternatives must be explored. This paper presents an efficient alternative to the Pareto based solution when considering both Minimum Sensitivity and Accuracy in multi-class classifiers. Alternatives are implemented by extending the Evolutionary Extreme Learning Machine algorithm for training artificial neural networks. Experiments were performed to select the best option after considering alternative proposals and related methods. Based on the experiments, this methodology is competitive in Accuracy, Minimum Sensitivity and efficiency. 相似文献
80.
Ruben Sevilla Sonia Fernández-Méndez Antonio Huerta 《Archives of Computational Methods in Engineering》2011,18(4):441-484
The development of NURBS-Enhanced Finite Element Method (NEFEM) is revisited. This technique allows a seamless integration
of the CAD boundary representation of the domain and the finite element method (FEM). The importance of the geometrical model
in finite element simulations is addressed and the benefits and potential of NEFEM are discussed and compared with respect
to other curved finite element techniques. 相似文献