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An exact and simple method to evaluate the frequency reuse efficiency for the reverse link of cellular CDMA systems over a non-uniform traffic distribution is presented. This method is based on a traffic redistribution and decomposition process and on standard curves with which partial reuse efficiencies are obtained and conveniently added to give the final parameter 相似文献
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Quantification of ethyl carbamate in cachaça produced in different agro‐industrial production systems
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Gabriel Biscotto d'Avila Maria das Graças Cardoso Wilder Douglas Santiago Leonardo Milani Avelar Rodrigues Bruno Leuzinger da Silva Rodolfo Romanielo Cardoso Alex Rodrigues Silva Caetano Cleusa de Fátima e Silva Ribeiro David Lee Nelson 《Journal of the Institute of Brewing》2016,122(2):299-303
Popularly known by various names such as caninha, dangerous, drips, damned and many other denominations, cachaça is the genuine Brazilian drink, produced by the fermentation of sugarcane juice by yeast, followed by distillation in alambics. Considering that cachaça is the most widely consumed distilled beverage from Brazil, the knowledge of the chemical composition and the presence of potentially toxic compounds such as ethyl carbamate, considered a human carcinogen, is important. The aim of this study was to evaluate the influence of different conditions of the agro‐industrial cachaça production systems, including the variety of sugarcane, on the quantification of ethyl carbamate through the chromatographic. Thirteen unaged beverage samples, produced from different varieties of sugarcane, were analysed. Using analysis of variance and comparison of average concentrations of ethyl carbamate (Scott–Knott, α = 5%), all of the samples were found to contain contaminant levels below the ceiling established by the legislation, which is 210 µg L?1. Copyright © 2016 The Institute of Brewing & Distilling 相似文献
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The importance of the efforts to bridge the gap between the connectionist and symbolic paradigms of artificial intelligence has been widely recognized. The merging of theory (background knowledge) and data learning (learning from examples) into neural-symbolic systems has indicated that such a learning system is more effective than purely symbolic or purely connectionist systems. Until recently, however, neural-symbolic systems were not able to fully represent, reason, and learn expressive languages other than classical propositional and fragments of first-order logic. In this article, we show that nonclassical logics, in particular propositional temporal logic and combinations of temporal and epistemic (modal) reasoning, can be effectively computed by artificial neural networks. We present the language of a connectionist temporal logic of knowledge (CTLK). We then present a temporal algorithm that translates CTLK theories into ensembles of neural networks and prove that the translation is correct. Finally, we apply CTLK to the muddy children puzzle, which has been widely used as a test-bed for distributed knowledge representation. We provide a complete solution to the puzzle with the use of simple neural networks, capable of reasoning about knowledge evolution in time and of knowledge acquisition through learning. 相似文献
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E Sosa M Scanavacca A d'Avila J Fukushima A Jatene 《Canadian Metallurgical Quarterly》1998,9(11):1133-1143
INTRODUCTION: Postinfarction ventricular tachycardia (VT), anteroseptal aneurysm, and ventricular dysfunction are commonly associated and predict a poor long-term prognosis. Surgical left ventricular reconstruction, which includes double plication of the anterior and septal wall, can improve ventricular function. This article analyzes the long-term efficacy of such a procedure to control recurrence of VT in a group of 50 consecutive patients. METHODS AND RESULTS: The study group consisted of 50 consecutive patients operated on between December 1986 and December 1994. The group comprised 44 men and 6 women. The mean age was 56+/-11 years. All patients had spontaneous VT following an anterior myocardial infarction. Twenty-five patients had two or more episodes of VT (eight presented as cardiac arrest, nine as syncope). Coronary artery disease was limited to the left anterior descending artery in 27 patients. An anteroseptal aneurysm was present in 49 patients. All patients had VT induced by programmed ventricular stimulation before surgery, and left ventricular reconstruction was performed without intraoperative mapping in all cases. Total mortality, VT recurrence, and sudden death rate were the endpoints of the study. In-hospital mortality was 8%. Postoperative left ventricular ejection fraction improved from 0.38 to 0.50 (P<0.05). Only two patients had postoperative inducible VT. Overall survival, VT recurrence rate, and sudden death rate were 73%, 12%, and 10%, respectively, after a median follow-up period of 6.25 years (0 to 8 years). CONCLUSION: Visually guided left ventricular reconstruction with septal and anterior wall plicature can be utilized effectively to treat recurrent VT associated with postinfarction anteroseptal aneurysm. 相似文献
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Roberta Perroni Marouço da Costa Cristiane Gimenes de Souza Rafael Cavalcante dos Santos Débora França de Andrade Luiz Antonio d'Avila 《European Journal of Lipid Science and Technology》2021,123(12):2100069
The purpose of this study is to develop and validate a method based on size-exclusion chromatography (SEC) for the simultaneous determination of fatty acid methyl esters (FAME), monoacylglycerols (MAG), diacylglycerols (DAG), and triacylglycerols (TAG) in biodiesel. The proposed method presents good linearity. The limits of detection are 0.26% mass for FAME, 0.02% mass for MAG, 0.01% mass for DAG, and 0.02% mass for TAG. The limits of quantification are 0.78% mass for FAME, 0.06% mass for MAG, 0.01% mass for DAG, and 0.06% mass for TAG. Accuracy evaluated by recovery yielded values ranging from 98.93% to 117.67%. Precision is evaluated by repeatability (%), which is ranged from 0.03% to 13.67%. The proposed SEC method proves effective in determining the FAME, MAG, DAG, and TAG content of standard samples, and the paired t-test shows that the results obtained were statistically similar to the gas chromatography (GC) values. The method also has some advantages over the reference GC methods, since it obtains the content for each class analyzed, irrespective of its components. Also, it does not require derivatization, which makes it easier and also quicker (15 min) than the 60 min taken by the two reference methods, and it does not need an internal standard, which makes it cheaper. Practical Applications: Size exclusion chromatography (SEC) is an efficient method for simultaneous and quantitative determination of fatty acid methyl esters (FAME), monoacylglycerols (MAG), diacylglycerols and triacylglycerols (TAG). The method present itself as an alternative to reference methods (ASTM D 6584 and ABNT NBR 15764) based on gas chromatography (GC). The proposed method shows advantages compared to reference methods, once it makes possible to determine the content of each constituent class in samples, regardless of its components, what makes the peak integration easier. Beyond that, previous sample derivatization is unnecessary, what makes the method simpler, cheaper and faster (15 min) than both reference methods that demands together 60 min for analysis (ASTM D 6584 for MAG, DAGa and TAG and ABNT NBR 15764 for FAME analysis). 相似文献
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