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71.
André Miguel F. Santos Rosa Maria dos Santos Pedro Miguel A.C. Castro Elsa Azevedo Luísa Sousa João Manuel R.S. Tavares 《Expert systems with applications》2013,40(16):6570-6579
A novel algorithm is proposed for the segmentation of the lumen and bifurcation boundaries of the carotid artery in B-mode ultrasound images. It uses the image contrast characteristics of the lumen and bifurcation of the carotid artery in relation to other tissues and structures for their identification. The relevant ultrasound data regarding the artery presented in the input image is identified using morphologic operators and processed by an anisotropic diffusion filter for speckle noise removal. The information obtained is then used to define two initial contours, one corresponding to the lumen and the other one regarding the bifurcation boundaries, for the application of the Chan-Vese level set segmentation model. A set of longitudinal ultrasound B-mode grayscale images of the common carotid artery was acquired using a GE Healthcare Vivid-e ultrasound system. The results reveal that the new algorithm is effective and robust, and that its main advantage relies on the automatic identification of the carotid lumen, which overcomes the known limitations of the traditional algorithms. 相似文献
72.
C. Cordoba A. Perez I. Aguirre De Carcer F. Jaque D. Henriques F. Carvalho 《International journal of remote sensing》2013,34(16):3473-3478
Measures of total ozone at Lisbon in July 1996 taken with a differential optical absorption filter instrument (UAM-DOAF) and a Dobson spectrophotometer are compared. Correlation of the UAM-DOAF measures and NOAATOVS data from April to October 1996 and NASA Earth Probe TOMS data from July to October 1996 for Madrid (40 N, 3 W) are given. Results show that the UAM-DOAF instrument can be used with approximately a 3 per cent error in estimating short-term total ozone variations. 相似文献
73.
Jordan Navarro Elsa Yousfi Jonathan Deniel Christophe Jallais Mercedes Bueno Alexandra Fort 《Ergonomics》2016,59(12):1553-1564
In the past, lane departure warnings (LDWs) were demonstrated to improve driving behaviours during lane departures but little is known about the effects of unreliable warnings. This experiment focused on the influence of false warnings alone or in combination with missed warnings and warning onset on assistance effectiveness and acceptance. Two assistance unreliability levels (33 and 17%) and two warning onsets (partial and full lane departure) were manipulated in order to investigate interaction. Results showed that assistance, regardless unreliability levels and warning onsets, improved driving behaviours during lane departure episodes and outside of these episodes by favouring better lane-keeping performances. Full lane departure and highly unreliable warnings, however, reduced assistance efficiency. Drivers’ assistance acceptance was better for the most reliable warnings and for the subsequent warnings. The data indicate that imperfect LDWs (false warnings or false and missed warnings) further improve driving behaviours compared to no assistance.
Practitioner Summary: This study revealed that imperfect lane departure warnings are able to significantly improve driving performances and that warning onset is a key element for assistance effectiveness and acceptance. The conclusion may be of particular interest for lane departure warning designers. 相似文献
74.
This paper proposes a new approach for the segmentation of both near-end and far-end intima-media regions of the common carotid artery in ultrasound images. The method requires minimal user interaction and is able to segment the near-end wall in arteries with large, hypoechogenic and irregular plaques, issues usually not considered previously due to the increased segmentation difficulty. 相似文献
75.
In this Letter, a new approach to build a neural model for the fast identification of spatiotemporal sequences is proposed. Such a model, the Stochastic Neural Sequence Identifier (SNSI), is simple and rapidly learns and identifies a given sequence. The SNSI receives as input several patterns belonging to a particular spatiotemporal sequence and produces as output a label for the sequence identified and a probability of this classification being correct. The SNSI is able to identify a sequence from patterns learned during training or novel ones, i.e., combinations of the sequence items distinct from those belonging to the trained set. The SNSI was tested on a 2D set of both closed and open trajectories with varying levels of complexity. The results suggest that the SNSI is able to recognize all the patterns presented in the training and most of the novel patterns used for testing. 相似文献
76.
Pedro Rangel Henriques Maria Joo Varanda Pereira Marjan Mernik Mitja Leni
Enis Avdi
auevi Viljem
umer 《Electronic Notes in Theoretical Computer Science》2002,65(3)
Many tools can be automatically derived from formal language definitions, such as compilers/interpreters, editors, analyzers, visualizers/animators, etc. Some examples of language-based tools generated automatically by the LISA system are described in the paper. In addition the specification of an algorithm animator and program visualizer, Alma, generated from an extended LISA input-grammar is discussed; LISA principles and code are reused in Alma implementation. 相似文献
77.
Katarzyna Skryplonek Marta Henriques David Gomes Jorge Viegas Catarina Fonseca Carlos Pereira Izabela Dmytrów Anna Mituniewicz-Małek 《Journal of dairy science》2019,102(9):7838-7848
Frozen yogurt is a type of dairy product that is considered to be a more healthful alternative to conventional ice cream due to its lower fat content and the presence of viable lactic acid bacteria. Lactose-free products are a growing trend in the dairy industry, and lactose-free yogurts and ice creams can both be found on the market. However, lactose-free frozen yogurt has not yet reached the market. In this study, we aimed to investigate the effect of adding κ-carrageenan (0.05, 0.1, and 0.15%) and corn starch (1, 2, and 3%) on acidity, texture, viscosity, overrun, melting properties, color attributes, and sensory characteristics of lactose-free frozen yogurts. Lactose was reduced by enzymatic hydrolysis during the fermentation process. The effectiveness of the hydrolysis was measured by HPLC, and lactose was reduced to 0.05% after 80 min of incubation with the enzyme. The addition of stabilizers did not change overrun and melting properties of frozen yogurt, but it did affect pH, titratable acidity, and color parameters. The product with 0.15% κ-carrageenan had the highest hardness and stickiness values. Moreover, κ-carrageenan had a positive effect on sensory attractiveness of lactose-free frozen yogurt, and it reduced the coarse texture in comparison with the control without stabilizers. A lactose-free frozen yogurt with good quality and nutritional characteristics was produced, particularly with the use of κ-carrageenan as stabilizer. 相似文献
78.
Laurent GueudréNicolas Bats Elsa Jolimaître 《Microporous and mesoporous materials》2012,147(1):310-317
Adsorption kinetics of cyclohexane in a variety of Silicalite-1 samples were measured by gravimetric uptake experiments. The kinetic appears as dependent upon the history of the crystals. Samples stored for several months before calcination (with their micropores full of template) exhibit a kinetic drop by almost an order of magnitude. Surprisingly, physico-chemicals analysis do not show any differences between these samples (no modification of their crystallinity or morphology, and no residual carbon is detected in the pore network). The kinetic drop is therefore attributed to a modification of the crystals surface, induced by a long-time contact with the template or cyclohexane molecules.Aged and as-synthesized (non-calcined) samples were etched by an HF solution, so as to “purify” the surface of the crystals. After a few minutes of treatment, the aged samples recover their initial adsorption kinetic, confirming that the kinetic drop is induced by the partial blocking of the entrance of the pores. Moreover, some of the as-synthesized crystals also show a rise of their adsorption kinetic, showing that surface resistance can be present ab initio, depending on the synthesis conditions.In an attempt to produce an accelerated aging effect, hydrothermal treatments were performed on non-calcined crystals. However, the treatments conditions are too severe, and induce variations in the crystal structure. 相似文献
79.
Carlos Henriques Olivier Marie Frdric Thibault-Starzyk Jean-Claude Lavalley 《Microporous and mesoporous materials》2001,50(2-3):167-171
NO+, generated from NO and O2, is an infrared probe for the differentiation of Brønsted sites in the main channels and side pockets of mordenites, and for the location and accessibility of sodium ions in the structure. Na+ ions in cationic positions in the main channels are replaced by NO+, and sodium nitrate is formed. The band assignment was checked by isotopic experiments. 相似文献
80.
Nutrition facts and functional potential of quinoa (Chenopodium quinoa willd.), an ancient Andean grain: a review 总被引:3,自引:0,他引:3
Antonio Vega‐Gálvez Margarita Miranda Judith Vergara Elsa Uribe Luis Puente Enrique A Martínez 《Journal of the science of food and agriculture》2010,90(15):2541-2547
Quinoa, Chenopodium quinoa Willd., is an Amaranthacean, stress‐tolerant plant cultivated along the Andes for the last 7000 years, challenging highly different environmental conditions ranging from Bolivia, up to 4.500 m of altitude, to sea level, in Chile. Its grains have higher nutritive value than traditional cereals and it is a promising worldwide cultivar for human consumption and nutrition. The quinoa has been called a pseudo‐cereal for botanical reasons but also because of its unusual composition and exceptional balance between oil, protein and fat. The quinoa is an excellent example of ‘functional food’ that aims at lowering the risk of various diseases. Functional properties are given also by minerals, vitamins, fatty acids and antioxidants that can make a strong contribution to human nutrition, particularly to protect cell membranes, with proven good results in brain neuronal functions. Its minerals work as cofactors in antioxidant enzymes, adding higher value to its rich proteins. Quinoa also contains phytohormones, which offer an advantage over other plant foods for human nutrition. Copyright © 2010 Society of Chemical Industry 相似文献