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81.
Jorge R. Chávez Fuentes Oscar R. González W. Steven Gray 《International journal of control》2018,91(6):1460-1472
This paper presents a symmetric Kronecker product analysis of independent and identically distributed jump linear systems to develop new, lower dimensional equations for the stability and performance analysis of this type of systems than what is currently available. In addition, new closed form expressions characterising multi-parameter relative sensitivity functions for performance metrics are introduced. The analysis technique is illustrated with a distributed fault-tolerant flight control example where the communication links are allowed to fail randomly. 相似文献
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Joana T. Pimenta Carlos Gonçalves Loic Hiliou Jorge F. J. Coelho Fernão D. Magalhães 《Journal of Coatings Technology and Research》2016,13(2):227-238
This study investigates the role of the polymeric binder on the properties and performance of an intumescent coating. Waterborne resins of different types (vinylic, acrylic, and styrene-acrylic) were incorporated in an intumescent paint formulation, and characterized extensively in terms of thermal degradation behavior, intumescence thickness, and thermal insulation. Thermal microscopy images of charred foam development provided further information on the particular performance of each type of coating upon heating. The best foam expansion and heat protection results were obtained with the vinyl binders. Rheological measurements showed a complex evolution of the viscoelastic characteristics of the materials with temperature. As an example, the vinyl binders unexpectedly hardened significantly after thermal degradation. The values of storage moduli obtained at the onset of foam blowing (melamine decomposition) were used to explain different intumescence expansion behaviors. 相似文献
86.
Fátima Barceló-Rico José-Luis Díez Jorge Bondia 《Knowledge and Information Systems》2012,30(2):377-403
This paper presents a method to find a model of a system based on the integration of a set of local models. Mainly, properties
are sought for the local models: independence of clusters and interpretability of their validity. This has been achieved through
the introduction of a possibilistic clustering for the first property and a pre-fixed shape of the membership functions for
the second one. A new cost index for the clustering optimization problem has been defined consisting of two terms: one for
global error and another for local errors. By giving higher importance to the local errors term, local models valid regionally
can be found. To avoid local optima and numerical issues, the parameters of the models are found using global optimization.
This new method has been applied to several data sets, and results show how the desired characteristics can be achieved in
the resulting models. 相似文献
87.
Jorge González-DomínguezAuthor Vitae Guillermo L. Taboada Author VitaeBasilio B. Fraguela Author Vitae María J. Martín Author VitaeJuan Touriño Author Vitae 《Computers & Electrical Engineering》2012,38(2):258-269
Servet is a suite of benchmarks focused on detecting a set of parameters with high influence on the overall performance of multicore systems. These parameters can be used for autotuning codes to increase their performance on multicore clusters. Although Servet has been proved to detect accurately cache hierarchies, bandwidths and bottlenecks in memory accesses, as well as the communication overhead among cores, up to now the impact of the use of this information on application performance optimization has not been assessed. This paper presents a novel algorithm that automatically uses Servet for mapping parallel applications on multicore systems and analyzes its impact on three testbeds using three different parallel programming models: message-passing, shared memory and partitioned global address space (PGAS). Our results show that a suitable mapping policy based on the data provided by this tool can significantly improve the performance of parallel applications without source code modification. 相似文献
88.
Angélica R. Jiménez‐Sánchez Israel Santillán Juvenal Rodriguez Resendiz Carlos A. Gonzalez‐Gutierrez Jorge D. Mendiola‐Santibañez 《International journal of imaging systems and technology》2012,22(2):137-144
In this article, a morphological contrast index based on the Weber's law is proposed to quantify the contrast in a processed image. This measure involves the contours of the image along with its background. The proposal made here is applied to detect the image with higher contrast, and also identify the enhanced image most similar to the original. Moreover, the contrast index is compared with other four indexes reported in the current literature. © 2012 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 22, 137–144, 2012 相似文献
89.
Francisca Castro Jorge Gomes Fernando C. de Sousa 《Creativity & Innovation Management》2012,21(2):171-182
This research investigates the connection between emotional intelligence (EI) and creativity. This was studied by exploring: (i) an association between leaders' EI and their followers' creative output; (ii) an association between six sub‐dimensions of EI and creativity; and (iii) a mediating role of climate in the link between EI and creativity. Two questionnaires (one for leaders and one for employees) were used to collect data in a hospital. Sixty‐six usable leader‐employee dyads were collected. The findings confirmed a positive relationship between leaders' EI and employees' creativity. At an EI's sub‐dimensions level, the current research showed an association between creativity, on one hand, and self‐encouragement and understanding of own emotions, on the other. Finally, no mediating effect of climate was observed. The absence of a mediating effect is interesting, since it suggests a direct link between leaders' EI and employees' creativity, regardless of the climate. This is important, since it calls attention to the paramount role of leaders in shaping individual and organizational behaviours as far as creativity is concerned. The paper also discusses implications for management and practice. 相似文献
90.
Thomas Gredig Mathew Werber Jorge L. Guerra Evan A. Silverstein Matthew P. Byrne Brian G. Cacha 《Journal of Superconductivity and Novel Magnetism》2012,25(7):2199-2203
The magnetic characteristics of iron phthalocyanine thin films are studied with a vibrating sample magnetometer, identifying a ferromagnetic transition temperature at 4.5?K. The metal ions at the center of the molecule are self-assembled along chains producing quasi one-dimensional magnetic chains of variable length in the thin films. The average chain length is varied from 20 to 300?nm via substrate temperature during deposition. Below the critical transition temperature, the magnetization curves have the shape of wasp-waisted or constricted loops. The in-plane chain length modulates the coercivity and saturation field and larger grains increase the coercivity significantly. First-order reversal curves of the wasp-waisted hysteresis loops reveal a long narrow strip that suggests a broad distribution of coercive fields and weak intergrain magnetic interactions. These findings are also supported through simulations based on the Preisach model. 相似文献