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81.
Vicente Milanés Joshué Pérez Jorge Godoy Enrique Onieva 《Expert systems with applications》2012,39(10):9097-9107
To decrease traffic accidents is a declared target of Intelligent Transportation Systems (ITS). Among them, rear-end collisions are one of the most common and constitute one of the as yet unsolved topics in the automotive sector. This paper presents an approach to the avoidance of rear-end collisions in congested traffic situations. To this end, two fuzzy controllers, a Collision Warning System (CWS) and a Collision Avoidance System (CAS), have been developed. The former is in charge of alerting the driver in case of an impending rear-end collision to prevent or mitigate the crash. The latter is in charge of generating an output control signal for the steering wheel in order to avoid the collision. Both CWS and CAS have been tested with real cars using vehicle-to-infrastructure (V2I) communications to acquire data of vehicles. A system installed in the infrastructure capable of assessing road traffic conditions in real time is responsible for transmitting the data of the vehicles in the surrounding area. The systems have been tested at the Center for Automation and Robotics (CAR)’s facilities with two mass-produced cars. 相似文献
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83.
Víctor Falguera Anabel Mengual Manuel Vicente Albert Ibarz 《Food research international (Ottawa, Ont.)》2010,43(3):882-885
Calcium pidolate is a calcium containing molecule that has the essential advantage of being absorbed more easily and in a greater proportion than any other calcium compound. The combination between a low methoxyl pectin and calcium allows forming food gels with a small amount of sugar. In this work, the use of calcium pidolate in the composition of two of these products (jams and gelatins) has been assayed, testing its rheological properties. An optimum content of calcium pidolate has been found for each product and sugar proportion. Both in jams and gelatins, the results obtained with calcium pidolate were better than the ones obtained with calcium chloride. 相似文献
84.
Luz M. Romo-Fernández Cristina López-Pujalte Vicente P. Guerrero Bote Félix Moya-Anegón 《Renewable Energy》2011,36(9):2529-2537
An overview is given of research in the major countries of Europe in the area of renewable energies. The analysis used the Scopus (Elsevier) database of scientific literature, calculating bibliometric indices (primary production, average citations per document, percentage variation, SJR, etc.) for the geographical domain of Europe during the period 2002–2007. The aim of the study is to supplement previous works on the subject which have mostly been limited to a particular type of energy without addressing the area as a whole, as well as to expand their methodological approaches in both the data retrieval strategy and the calculation of indices. The results show Europe to be well positioned globally in this scientific field – in production, in citations, and in impact. 相似文献
85.
Construction safety management involves complex issues (e.g., different trades, multi-organizational project structure, constantly changing work environment, and transient workforce). Systems thinking is widely considered as an effective approach to understanding and managing the complexity. This paper aims to better understand dynamic complexity of construction safety management by exploring archetypes of construction safety. To achieve this, this paper adopted the ground theory method (GTM) and 22 interviews were conducted with participants in various positions (government safety inspector, client, health and safety manager, safety consultant, safety auditor, and safety researcher). Eight archetypes were emerged from the collected data: (1) safety regulations, (2) incentive programs, (3) procurement and safety, (4) safety management in small businesses (5) production and safety, (6) workers’ conflicting goals, (7) blame on workers, and (8) reactive and proactive learning. These archetypes capture the interactions between a wide range of factors within various hierarchical levels and subsystems. As a free-standing tool, they advance the understanding of dynamic complexity of construction safety management and provide systemic insights into dealing with the complexity. They also can facilitate system dynamics modelling of construction safety process. 相似文献
86.
Metformin Reduces Lipogenesis Markers in Obese Mice Fed a Low-Carbohydrate and High-Fat Diet
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Karla Nayara de Oliveira Santana Deborah Farias Lelis Keila Lopes Mendes Jamille Fernandes Lula Alanna Fernandes Paraíso João Marcus Oliveira Andrade John David Feltenberger Junio Cota Diego Vicente da Costa Alfredo Mauricio Batista de Paula André Luiz Sena Guimarães Sérgio Henrique Sousa Santos 《Lipids》2016,51(12):1375-1384
Lipogenesis is the process by which fatty acids are synthesized. In metabolic syndrome, an insulin resistant state along with high plasma levels of free fatty acids (FFA) and hyperglycemia may contribute to the lipogenic process. The aim of the present study was to investigate the effects of oral administration of metformin on the expression of lipogenic genes and glycemic profile in mice fed with low‐carbohydrate high‐fat diet by evaluating their metabolic profile. SWISS male mice were divided into 4 groups (N = 7) that were fed with standard (ST), standard plus metformin (ST + MET), low‐carbohydrate high‐fat diet (LCHFD) and low‐carbohydrate high‐fat diet plus metformin (LCHFD + MET) (100 mg kg?1 diet) diets respectively. Food intake, body weight and blood parameters, such as glucose tolerance, insulin sensitivity, glucose, HDL‐c, total cholesterol, triglycerides, ASL and ALT levels were assessed. Histological analyses were performed on hematoxylin and eosin‐stained epididymal adipose tissue histological specimens. The expression levels of peroxisome proliferator‐activated receptor (PPARγ), sterol regulatory element‐binding protein 1 (SREBP1), fatty acid synthase (FAS) and acetyl‐CoA carboxylase (ACC), were assessed by RT‐PCR. This study showed that metformin decreased adipocyte area, body weight and food consumption in obese animals when compared to the standard group. Furthermore, the expression of lipogenic markers in adipose tissue were diminished in obese animals treated with metformin. This data showed that oral administration of metformin improved glucose and lipid metabolic parameters in white adipose tissue by reducing the expression of lipogenesis markers, suggesting an important clinical application of MET in treating obesity‐related diseases in metabolic syndrome. 相似文献
87.
José Gedael Fagundes Junior Rodolfo da Silva Manera Ruís Camargo Tokimatsu Vicente Afonso Ventrella Juno Gallego 《Welding International》2016,30(7):520-526
Equipment of sugar cane plants and mineral extraction are submitted to severe abrasive wear conditions. Welded hardfacings are usually applied to repair this kind of damage, where commercial chromium/carbon-rich welding consumables have usually been employed. In the present work we investigated the microstructure of experimental hardfacings made by addition of residues (chips) collected from the machining of ASTM F67 (unalloyed Ti, grade 4) alloy. Mixtures with different carbide-formers (Cr/Nb ferro-alloys) were also tested. Two layers of ‘pure’ chips (Ti), chips plus Fe–Cr (Ti–Cr), and chips plus Fe–Nb (Ti–Nb) were applied on low-carbon steel specimens by the GTAW/TIG process. The microstructure of hardfacing layers was observed by optical and scanning electron microscopy (SEM) equipped with EDS microanalysis. The microstructural characterization has determined that carbide distributions change significantly with the chemical nature of the hardfacing. SEM observations coupled with EDS microanalysis have confirmed the formation of complex carbides within the metal weld, whose stoichiometry was determined by X-ray diffraction (XRD) analysis. Mixed carbides of MC type and some cementite have been found. As a result it was suggested that use of ASTM F67 chips as carbide formers for composition of welding consumables can contribute to improved wear resistance of hardfacings, if compared with traditional chromium-based hardfacings. 相似文献
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89.
Miguel A Rosales Luis M Cervilla Eva Sánchez‐Rodríguez María del Mar Rubio‐Wilhelmi Begoña Blasco Juan J Ríos Teresa Soriano Nicolás Castilla Luis Romero Juan M Ruiz 《Journal of the science of food and agriculture》2011,91(1):152-162
BACKGROUND: The aim of this study was to examine how different environmental factors (temperature, solar radiation, and vapour‐pressure deficit [VPD]) influenced nutritional quality and flavour of cherry tomato fruits (Solanum lycopersicum L. cv. Naomi) grown in two types of experimental Mediterranean greenhouses: parral (low technology) and multispan (high technology). RESULTS: Fruits were sampled three times during 3 years (2004, 2005 and 2006): at the beginning, middle and end of the fruit production period. Values for temperature, solar radiation, and VPD peaked in the third sampling in both greenhouses; values were higher in the parral‐type greenhouse, triggering abiotic stress. This stress reduced the accumulation of lycopene and essential elements, augmenting the phytonutrient content and the antioxidant capacity of tomatoes. During the third sampling, sugars were increased while organic acid content diminished, producing tomatoes with a sweeter‐milder flavour. The parral greenhouse produced tomatoes with higher phenolic compounds and ascorbic acid contents, together with a greater antioxidant capacity, without showing differences in flavour parameters. CONCLUSION: The higher phytonutrients content and antioxidant activity during the environmental stress, more pronounced in parral than multispan greenhouse, together with the sweeter‐milder flavour, conferred a notable nutritional benefit, which considerably improved the nutritional and organoleptic quality of these tomatoes. Copyright © 2010 Society of Chemical Industry 相似文献
90.
Mar��a-Pilar S��enz-Navajas Federico Echavarri Vicente Ferreira Purificaci��n Fern��ndez-Zurbano 《European Food Research and Technology》2011,232(5):877-887
Anthocyanins play a crucial role in wine color. Thus, their analysis results essential for evaluating their contribution to perceived color in wines, attribute directly linked to quality judgements. In this context, this study was aimed at: (1) defining the color space of a relative large number of commercial oaked Spanish red wines and (2) establishing a linkage between wine coloring, anthocyanic composition, and quality perception of this set of wines. Therefore, CIELab parameters (a 10*, b 10*, L 10*), monomeric anthocyanin contents analyzed by HPLC with ultraviolet and mass detection, and polymeric pigment content estimated by a protein precipitation assay combined with bisulfite bleaching were evaluated in a total of 58 wine samples. Principal component analysis was performed on color variables, and their correlations were discussed. The results have evidenced the important role played by the pyranoanthocyanic compounds since they seem to be the main contributors to the red color of these aged wines, and they have been demonstrated not to increase their yellow nuances. On the other hand, results highlight that, regardless of the time of aging, wines presenting more red (higher values for a 10* and for low molecular weighted anthocyanins) and lower yellow nuances (lower values for b 10* and T) as well as a darker color (lower in L 10* and higher in CI) are in general evaluated with higher quality scores by wine experts. 相似文献