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21.
Smith P. Shah M. da Vitoria Lobo N. 《Intelligent Transportation Systems, IEEE Transactions on》2003,4(4):205-218
This paper presents a system for analyzing human driver visual attention. The system relies on estimation of global motion and color statistics to robustly track a person's head and facial features. The system is fully automatic, it can initialize automatically, and reinitialize when necessary. The system classifies rotation in all viewing directions, detects eye/mouth occlusion, detects eye blinking and eye closure, and recovers the three dimensional gaze of the eyes. In addition, the system is able to track both through occlusion due to eye blinking, and eye closure, large mouth movement, and also through occlusion due to rotation. Even when the face is fully occluded due to rotation, the system does not break down. Further the system is able to track through yawning, which is a large local mouth motion. Finally, results are presented, and future work on how this system can be used for more advanced driver visual attention monitoring is discussed. 相似文献
22.
Anupam Glorious Lobo Abdul Mujeeb Mahammad Nawaz Adeeb Aman A. P. Abdul Basith 《Polymer-Plastics Technology and Engineering》2016,55(16):1713-1719
Elucidation of the structure of naturally existing or synthesized substances is an important criterion in the study of materials to predict the application of the substance. In this study, polylactide was doped with nano-aluminium oxide and nano-cupric oxide with 1 and 3 mg of concentration variants. The interaction between the polymer matrix and the nanoparticles has been studied using Fourier transform infrared. Successful doping of the polymer has been observed. Attention has been drawn to check the intermolecular bonding in films having varying thicknesses, films prepared at higher sonication temperatures, and chemical homogeneity of the doped polymer films. 相似文献
23.
Michelle C. Barbosa Nigel R. Messmer Tayra R. Brazil Fernanda R. Marciano Anderson O. Lobo 《Materials science & engineering. C, Materials for biological applications》2013,33(5):2620-2625
Nanohydroxyapatite (nHAp) powders were produced via aqueous precipitation by adopting four different experimental conditions, assisted or non-assisted by ultrasound irradiation (UI). The nHAp powders were characterized by X-ray diffraction, energy-dispersive X-ray fluorescence, Raman and attenuated total reflection Fourier transform infrared spectroscopies, which showed typical surface chemical compositions of nHAp. Analysis found strong connections between UI and the crystallization process, crystal growth properties, as well as correlations between calcination and substitution reactions. 相似文献
24.
Daniel Lobo Mauricio Solano George A. Bubenik Michael Levin 《Journal of the Royal Society Interface》2014,11(92)
A fundamental assumption of today''s molecular genetics paradigm is that complex morphology emerges from the combined activity of low-level processes involving proteins and nucleic acids. An inherent characteristic of such nonlinear encodings is the difficulty of creating the genetic and epigenetic information that will produce a given self-assembling complex morphology. This ‘inverse problem’ is vital not only for understanding the evolution, development and regeneration of bodyplans, but also for synthetic biology efforts that seek to engineer biological shapes. Importantly, the regenerative mechanisms in deer antlers, planarian worms and fiddler crabs can solve an inverse problem: their target morphology can be altered specifically and stably by injuries in particular locations. Here, we discuss the class of models that use pre-specified morphological goal states and propose the existence of a linear encoding of the target morphology, making the inverse problem easy for these organisms to solve. Indeed, many model organisms such as Drosophila, hydra and Xenopus also develop according to nonlinear encodings producing linear encodings of their final morphologies. We propose the development of testable models of regeneration regulation that combine emergence with a top-down specification of shape by linear encodings of target morphology, driving transformative applications in biomedicine and synthetic bioengineering. 相似文献
25.
Ana M. Herrera-González Martín Caldera-Villalobos Jesús García-Serrano Marissa Vargas Ramírez Azdrubal Lobo Guerrero-Serrano 《Designed Monomers and Polymers》2018,21(1):137-144
In this paper we report the synthesis of a new polyacrylate named poly(1,1?-BP4MA) which is a derivate from 4-biphenylmethanol monomer. Poly(1,1?-BP4MA) was obtained by solution and bulk polymerization techniques to yield polymers with high molecular weight and high solubility. The study of the optical properties showed that poly(1,1?-BP4MA) is a fluorescent material with emission in the UV-green region and it has similar quantum yield to tryptophan. 相似文献
26.
Philippe Owezarski Jorge Lobo Deep Medhi 《Journal of Network and Systems Management》2013,21(4):707-712
This short paper reports on the CNSM’2012 conference (International Conference on Network and Service Management). It presents an overview on the technical sessions, keynotes, tutorials, and panel, especially focusing on the original and dominating topics that raised the most comments and discussion. It then aims at indicating what the dominant research directions were in the network and service management community. 相似文献
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29.
George F. Finco Karina G. Fiametti Viviane da Silva Lobo Edson A. da Silva Fernando Palú João H. C. Wancura Maria L. F. Rodrigues Alexsandra Valério José Vladimir de Oliveira 《Journal of the American Oil Chemists' Society》2022,99(7):559-568
Monoacylglycerol (MAG) and diacylglycerol (DAG) are two natural components found in most edible oils and fats. Conventional synthesis of MAG and DAG is usually conducted by glycerolysis of triacylglycerol (TAG) at high temperatures (above 200°C) in the presence of an alkaline catalyst. In this work, the synthesis of MAG and DAG using enzymatic glycerolysis of olive oil was investigated using Tween 80 as surfactant, n-butanol as co-surfactant and the novel lipase in free/liquid formulation Lipozyme TL 100L as catalyst. Experimental design was used to evaluate the effect of enzyme load and reaction temperature on the feedstock conversion. Enzyme load and system temperature were significant variables in the statistical design and the best condition was found at 35°C, 7.5 vol% of Lipozyme TL 100L and glycerol to oil volumetric ratio of 2:1 with conversion of TAG at approximately 98% after 2 h of process. A mathematical model based on the Ping-Pong Bi-Bi mechanism was used to describe the reaction kinetics. The model adequately described the behavior of the system and can be a useful tool for the design of reactors in larger scales. 相似文献
30.
M Pilar Cano Begoa de Ancos M Gloria Lobo Marianne Monreal 《Journal of the science of food and agriculture》1996,71(3):351-358
The predominant carotenoids in extracts of female and hermaphrodite Papaya fruits (Carica papaya L) Solo cv Sunrise were determined by high-performance liquid chromatography on a C18 reversed-phase column using a diode-array detector. Three classes of carotenoids were separated and identified from the papaya extract without saponification; these were xanthophylls, hydrocarbon carotenoids and carotenol fatty acid esters. The xanthophylls were identified as trans-zeaxanthin, cryptoflavin and β-cryptoxanthin; other xanthophyls were detected in very small quantities. The major hydrocarbon carotenoid was identified as lycopene. Carotenol fatty acid esters were identified as carotenol fatty acid esters of β-cryptoxanthin, cryptoxanthin-5,6-epoxide, lutein, zeaxanthin and violaxanthin. There were no qualitative differences among the carotenoid pattern of female and hermaphrodite papaya fruits. Changes in carotenoid composition during ripening in hermaphrodite and female papaya fruits (cv Sunrise) were investigated in three different stages of ripeness. These changes could be shown in terms of Hunter colour values. 相似文献