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Mobile Networks and Applications - The text mining process typically involves the application of natural language processing (NLP) techniques, in order to obtain important information and extract...  相似文献   
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Six olive oils extracted from the cultivars Arbequina, Arbosana, Coratina, Frantoio, Koroneiki, and Picual from 2017 and 2018 harvests, cultivated in Pinheiro Machado, Rio Grande do Sul, Brazil, are evaluated for standard oil composition parameters and bioactive constituents (pigments, tocopherols, and phenolic compounds). Multivariate principal component analysis (PCA) and univariate ANOVA and Fisher's LSD test are used to verify the effect of cultivar and harvest year on oil composition. Olive oil composition met extra virgin olive oil (EVOO) standard parameters and is influenced by both cultivar and harvest year. EVOO produced in 2018 has greater chlorophyll, caffeic acid, ligstroside aglycone, hydroxyoleuropein aglycone, syringic acid, and hydroxytyrosol acetate contents than the EVOOs from 2017. Linoleic acid, ferulic acid, ligstroside aglycone, and hydroxytyrosol acetate are the variables whose contents most contributed to the differentiation of oils by cultivar in both harvest years. Chemical characterization analyses allow for the differentiation of oil composition based on harvest year and cultivar. Metabolic quality data obtained here support the establishment of a local EVOO profile and the compounds that most contributed to treatment differentiation may serve as markers that can be utilized in determining origin, cultivar, and harvest year. Practical Applications: Olive production in Brazil is recent and is based on European cultivars which have not been bred for the local environmental conditions. Therefore, the measurement of olive oil metabolic quality will determine cultivar adaptability to local edaphoclimatic conditions as well as assist in the establishment of a standard of identity for the product and promote the development of its market. Olive oil produced in Southern Brazil shows high quality, and is especially rich in phenolic compounds. Although harvest year influences oil composition, oil from both harvests meet EVOO standards and cultivar specific metabolic markers are observed. This study provides the foundation for olive producers in Southern Brazil to seek authentication of the geographical origin of olive oil.  相似文献   
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The performance of an adsorption icemaker prototype operating in a double-stage mass recovery cycle was experimentally investigated under the generation temperature of 75°C. The prototype was heated in the regeneration phase by an electric heater, and an analytical model was employed to assess the daily number of cycles and the ice production, if evacuated tube solar collectors were used to supply the regeneration heat. It was found that the parasitic heat consumed by the metallic part of the reactor greatly reduced the coefficient of performance (COP) and ice production per unit area of solar collector. A reduction of the parasitic heat by 60% would increase the COP in 54%, and the daily ice production per unit area of solar collector in 50 to 54%, depending on the insolation. The performance of the studied prototype was inferior to the performance of some prototypes presented in the literature, which were directly heated by solar energy and used methanol as refrigerant, but this type of prototype could be an alternative to avoid subatmospheric working pressures and to provide ice on rainy and low insolation days, if waste heat or another heat source is available.  相似文献   
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Soy protein isolate (SPI) was hydrolyzed with Flavourzyme® (SHF) or chymotrypsin (SHC). Hydrolysates were sequencially fractionated by ultrafiltration using different membrane pore sizes (50, 10, and 3 kDa). The antioxidant ability of each hydrolysate protein fraction was tested in a liposome oxidizing system and their free radical scavenging activity (FRSA) was evaluated with the DPPH method (diphenylpicrilhydrazine radical). Molecular weight (MW) distribution, solubility, surface hydrophobicity, and amino acid composition of each SPI hydrolysate fraction were measured and their effect on antioxidant and scavenging activities was established by multivariate correlation. The most active ultrafiltrated peptide fractions (P < 0.05), from SHF and SHC, had of MW of <3 kDa (F3 and C3, respectively). These fractions decreased liposome oxidation by 83.2% and 84.5%, respectively, and also showed the highest FRSA (F3: 21.3% and C3: 24.4%). In addition to molecular size, the antioxidant activity and FRSA of soy protein fractions were related to their amino acid composition, especially to an increased content of Phe and a lowered content of Lys. Also, hydrophobicity of ultrafiltrated peptide fractions was an important characteristic (P < 0.001) associated with their ability to trap free radicals. Ultrafiltered peptide fractions with low MW have a high potential to be used as natural alternatives to prevent lipid oxidation in foods.  相似文献   
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Studies based on AC high voltage tests have been done at Cepel to investigate the performance of 800 kV bushar insulators under heavy wetting conditions. Insulators were tested which are now used on si...  相似文献   
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Chromium carbide-based thermally sprayed coatings are widely used for high temperature wear applications (typical temperature range from 540 to 900 °C). In these extreme environments at those temperatures, several phenomena will degrade, oxidize, and change the microstructure of the coatings, thereby affecting their wear behavior. Although it can be easily conceived that the Cr3C2-NiCr coating microstructure evolution after high temperature exposure will depend on the as-sprayed microstructure and spraying parameters, very little has been done in this regard. This study intends to develop a better understanding of the effect of spraying parameters on the resulting chromium carbide coating microstructure after high temperature operation and high temperature sliding wear properties. The microstructures of different coatings produced from two morphologies of Cr3C2-NiCr powders and under a window of in-flight particle temperature and velocity values were characterized through x-ray diffraction and scanning electron microscopy. Sliding wear at 800 °C was performed and the wear behavior correlated with the spraying parameters and coating microstructure. Vickers microhardness (300 gf) of the coatings before and after sliding wear was also measured.  相似文献   
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The use of diffusers around the horizontal-axis wind turbines has been widely studied since the diffuser improves the power coefficient of the turbine and it is often called DAWTs (diffuser augmented wind turbines).Turbines using diffuser are called DWATs (Diffuser Augmented Turbines),and have efficiency bigger than the Betz limit (maximum energy flow extracted = 59.26%). Thus, this study presents a mathematical model describing the behavior of the velocity profile internally to a diffuser according to the characteristics of flow and geometry of a conical diffuser. The results are compared with experimental data and show good agreement.  相似文献   
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In this paper, we apply performance evaluation and capacity allocation models to support decisions in the design (or redesign) and planning of a job-shop queueing network of a metallurgical plant. Approximate parametric decomposition methods are used to evaluate system performance measures, such as the expected work-in-process (WIP) and production leadtimes. Based on these methods, optimisation models are then applied for the allocation (or reallocation) of capacity to the stations of the job-shop network. These models are also used to generate approximate trade-off curves between capacity investment and WIP or leadtime, which are valuable for a production manager to estimate how much capacity should be allocated to the stations to reach some targeted performance measures. These curves are also useful for the sensitivity analysis of the solutions to changes in the input parameters, such as the variability of the product demands, the mix of the production and the throughput rate of the network.  相似文献   
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