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93.
Marcos Eduardo Valle Raul Ambrozio Valente 《Journal of Mathematical Imaging and Vision》2017,57(2):183-201
Mathematical morphology is a theory with applications in image processing and analysis. This paper presents a quantale-based approach to color morphology based on the CIELab color space in spherical coordinates. The novel morphological operations take into account the perceptual difference between color elements by using a distance-based ordering scheme. Furthermore, the novel approach allows for the use of non-flat structuring elements. An illustrative example reveals that non-flat dilations and erosions may preserve more features of a color image than their corresponding flat operations. Furthermore, the novel non-flat morphological operators yielded promising results on experiments concerning the detection of the boundaries of objects on color images. 相似文献
94.
M. Maczka A.G. Souza Filho W. Paraguassu P.T.C. Freire J. Mendes Filho J. Hanuza 《Progress in Materials Science》2012,57(7):1335-1381
High pressure has been one of key tools for discovering and accessing new phases and novel properties of materials. Under these extreme conditions, it is possible to obtain information about the structural instabilities and to probe the delicate balance between short and long range interactions, which is fundamental for understanding the emergence of many properties. In this paper we reviewed the high-pressure behavior of some molybdate and tungstate materials, which comprises a large class of inorganic compounds that exhibit interesting physical properties (optical, ferroelastic, ferroelectric, negative thermal expansion) and have technological applications in different fields. These materials have a rich polymorphism in high pressures and some of them exhibit pressure-induced amorphization, thus making molybdates and tungstates compounds good prototypes to exploit new concepts about the physics of amorphization processes and about chemical decomposition under high pressure. We discussed how the combination of short and long-range probe techniques (which gives detailed information on the structural changes occurring in these materials) under high-pressures provides significant insight into the origin of lattice instabilities and pressure-induced amorphization in this particular class of inorganic materials. Furthermore, we reviewed in detail, how these structural changes affect their optical and ferroelectric properties. The conclusions derived from the high-pressure studies duly reviewed herewith have important implications for science and applications of these materials. 相似文献
95.
Andrea Carrara Ge?cze Evelyn de Souza Oliveira Katalin Carrara Ge?cze Raquel Mendon?a Alvarenga Marcus H. Canuto Helmuth G. L. Siebald 《European Food Research and Technology》2012,235(5):853-859
Brazilian cacha?a can be produced in two different ways: distilled in stainless steel column or in copper alembic stills. We evaluated 36 samples of commercial non-aged cacha?as: 18 samples of sweetened cacha?as distilled in stainless steel column, and 18 samples distilled in copper alembic stills. Fingerprints were obtained through electrospray ionization mass spectrometry by recording the intensity of the 15 most abundant ions. Principal component analysis was applied to the data and separated the samples in two groups. However, after sample standardization with sugar (20?g?L?1), it was not possible to group them by type of distillation. The results showed that the technique applied did not allow differentiation of cacha?as based on the distillation system, but for the presence or absence of sugar in them. 相似文献
96.
This paper presents a non-prioritized belief change operator, designed specifically for incorporating new information from many heterogeneous sources in an uncertain environment. We take into account that sources may be untrustworthy and provide a principled method for dealing with the reception of contradictory information. We specify a novel Data-Oriented Belief Revision Operator, that uses a trust model, subjective logic, and a preference-based argumentation framework to evaluate novel information and change the agent’s belief set accordingly. We apply this belief change operator in a collaborative traffic scenario, where we show that (1) some form of trust-based non-prioritized belief change operator is necessary, and (2) in a direct comparison between our operator and a previous proposition, our operator performs at least as well in all scenarios, and significantly better in some. 相似文献
97.
Carlos Elias Helio Lopes Victor Vieira Leticia Souza Márcia Vieira 《Journal of Materials Engineering and Performance》2014,23(7):2533-2538
This study analyzed the influences of manufacturing process (twisting and machining) and surface finishing on the angular distortion, maximum torque, and toughness of two NiTi endodontic instruments (Race—FKG Dentaire and TF—Twisted Files, SybronEndo). Statistical analysis of results showed that TF instruments (twisted) had higher distortion angle (p < 0.05) and lower maximum torque to fracture (p < 0.05) than Race instruments (machined). SEM analysis of fractured instruments showed a surface morphology characteristic of ductile fracture, with plastic deformation in the helical shafts. The results suggest that both instruments are equally suitable for clinical applications. This study is purely scientific as it evaluates only some material properties, and is not intended to endorse a commercial product. 相似文献
98.
Rhana Amanda Ribeiro Teodoro Regiane Victória de Barros Fernandes Diego Alvarenga Botrel Soraia Vilela Borges Amanda Umbelina de Souza 《Food and Bioprocess Technology》2014,7(9):2560-2569
This study aimed to characterize rosemary essential oil particles obtained by spray-drying and to evaluate their antimicrobial activity. Measurements of mycelial growth of Penicillium and Aspergillus fungi, isolated from fresh dough, were made applying oil concentrations of 1.0, 5.0, 10.0, 20.0, and 50.0 μL/mL. Fungi and yeast counts in the fresh dough submitted to the control (no oil), pure oil, and microencapsulated oil treatments were also conducted. The microcapsules showed 50 % oil retention after drying, and the major oil components identified were 1,8-cineole (29.0 %), camphor (26.6 %), and α-pinene (10.6 %). The analysis of the particles revealed surfaces without fissures, with a mean particle size of 12.2 μm and presenting an amorphous structure. The growth inhibiting effect of Penicillium sp. fungus, compared to the control, was verified at concentrations of 1.0, 5.0, and 10.0 μL/mL rosemary essential oil, which did not differ among them. For Aspergillus sp., the application of 10.0 μL/mL oil provided greater inhibition compared to 1.0 and 5.0 μL/mL. Complete inhibition occurred with the application of 50.0 μL/mL for both fungal genera tested. At 8 days of dough storage at 25 °C, a decrease of at least 0.7 and 1.5 log cycles of fungal growth was observed in the dough with pure oil and that with microencapsulated oil, respectively, relative to the control. The microencapsulation process retained the antimicrobial property of rosemary essential oil and provided further extension of this activity over time when applied to fresh dough. 相似文献
99.
A two-way coupled multiscale model for predicting damage-associated performance of asphaltic roadways 总被引:1,自引:1,他引:0
Yong-Rak Kim Flavio V. Souza Jamilla Emi Sudo Lutif Teixeira 《Computational Mechanics》2013,51(2):187-201
This paper presents a quasi-static multiscale computational model with its verification and rational applications to mechanical behavior predictions of asphaltic roadways that are subject to viscoelastic deformation and fracture damage. The multiscale model is based on continuum thermo-mechanics and is implemented using a finite element formulation. Two length scales (global and local) are two-way coupled in the model framework by linking a homogenized global scale to a heterogeneous local scale representative volume element. With the unique multiscaling and the use of the finite element technique, it is possible to take into account the effect of material heterogeneity, viscoelasticity, and anisotropic damage accumulation in the small scale on the overall performance of larger scale structures. Along with the theoretical model formulation, two example problems are shown: one to verify the model and its computational benefits through comparisons with analytical solutions and single-scale simulation results, and the other to demonstrate the applicability of the approach to model general roadway structures where material viscoelasticity and cohesive zone fracture are involved. 相似文献
100.
Rafael Balbino Cardoso Luiz Augusto Horta Nogueira Edson Palhares de Souza Jamil Haddad 《Energy Efficiency》2012,5(3):433-446
Increasing efficiency of electrical equipment is essential to national energy rationality, enabling energy consumption reduction and postponing inversion in distribution, transmission and generation, as well as mitigating environmental impacts associated with such activities. Considering such purposes, two actions have been promoted in Brazil: (a) minimum energy performance standards (MEPS) have been required for some appliances and (b) consumers have been informed about the most efficient products by ??endorsement labeling.?? The purpose of this study is to assess window and split air-conditioners with Brazilian MEPS. To evaluate the impact of efficient air-conditioners in this market, a model was developed based on estimates for quantity of equipment in operation and unitary consumption, as determined by local temperature records. From this model, it was deduced that using only efficient conditioners (class A for Brazilian Labeling Program/INMETRO, with PROCEL Label) an annual saving of 322?GWh and a reduction in demand of 109?MW could be obtained in 2007. Furthermore, it was observed that the current MEPS established by Brazilian legislation for air-conditioners may be considered relatively low. Considering that MEPS are similar to those observed in China (the main exporter of air-conditioners to the Brazil), an energy saving of roughly 222?GWh could be achieved in the same year. Impacts on emission of greenhouse gases are also estimated. 相似文献