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91.
We propose mathematical programming models for solving problems arising from planning and running an energy production process based on burning biomasses. The models take into account different aspects of the problem: determination of the biomasses to produce and/or buy, transportation decisions to convey the materials to the respective plants, and plant site locations. Whereas the “running model” is linear, we propose two “planning models”, both of which are mixed-integer nonlinear programming problems. We show that a spatial branch-and-bound type algorithm applied to them is guaranteed to converge to an exact optimum in a finite number of steps. 相似文献
92.
The “antioxidant power” of a food is an expression of its capability both to defend the human organism from the action of the free radicals and to prevent degenerative disorders deriving from persistent oxidative stress. Purpose of this study is to analyse the antioxidant capacity (measured by means of the crocin bleaching method) of several samples of Sicilian red wines and to evaluate their dependency on the vintage and on the grape variety. Finally, the correlation between the single flavonoids compounds and the antioxidant capacity has been investigated. The analyses show that the antioxidant properties of red wine appear to be unequally influenced by the vintages for the different cultivars and that the correlation between antioxidant capacity and the total phenolic contents is weak. The latter can be explained by the fact that the wine’s antioxidant properties are influenced differently by each polyphenolic molecule. 相似文献
93.
Sergio M. Bonesi Esther Carbonell Hermenegildo Garcia Maurizio Fagnoni Angelo Albini 《Applied catalysis. B, Environmental》2008,79(4):368-375
Solid photocatalysts in which the 2,4,6-triphenylpyrylium (TP) or 2,4,6-triphenylthiapyrylium cation (TTP) are encapsulated within zeolite Y or deposited on mesoporous silica are used as photosensitizers for the oxidation of sulfides, both aromatic and aliphatic, in solvents of various polarity. Contrary to the same cations in solution, these solid sensitizers are not significantly degraded during operation. An effective oxygenation takes place leading to sulfoxides, disulfides, sulfinic and sulfenic esters as well as sulfonic acids. This large scope method shows a limited dependence on the substrate structure and on conditions and is suitable for the abatement of sulfur-containing pollutants. 相似文献
94.
采用动量积分方法分析压水堆发生失水事故时在安全壳的内表面上的液膜凝结、再浸润和蒸发过程。由凝结液膜的质量和动量守恒方程导出了凝结液膜在延展表面的子午线方向平均速度的积分-微分方程。假设液膜以层流的方式流动,把导出的积分-微分方程变成容易进行数值积分的液膜速度的一阶常微分方程,由此求得液膜厚度分布。液膜能量守恒方程的解给出了安全壳内壁面的温度分布。 相似文献
95.
Software Quality Journal - In the last few years, Internet of Things (IoT) systems have drastically increased their relevance in many fundamental sectors. For this reason, assuring their quality is... 相似文献
96.
Peter Zalar Lucia Rubino Fatima Margani Gerwin Kirchner Daniele Raiteri Maurizio Stefano Galimberti Vincenzina Barbera 《Advanced Engineering Materials》2023,25(17):2300706
Inspired by decades of research in the compatibilization of fillers into elastomeric composites for high-performance materials, a novel polyurethane-based stretchable carbon ink is created by taking advantage of a Janus molecule, 2-(2,5-dimethyl-1H-pyrrol-1-yl)propane-1,3-diol (serinol pyrrole, SP). SP is used to functionalize the carbon and comonomer in the polymer phase. The use of SPs in both the organic and inorganic phases results in an improved interaction between the two phases. When printed, the functionalized material has a factor 1.5 lower resistance-strain dependence when compared to its unfunctionalized analogue. This behavior is superior to commercially available carbon inks. To demonstrate the suitability of ink in an industrial application, an all-printed, elastomer-based force sensor is fabricated. This “pyrrole methodology” is scalable and broadly applicable, laying the foundation for the realization of printed functionalities with improved electromechanical performance. 相似文献
97.
The roadmap approach to robot path planning is one of the earliest methods. Since then, many different algorithms for building roadmaps have been proposed and widely implemented in mobile robots but their use has always been limited to planning in static, totally known environments. In this paper we combine the use of dynamic analogical representations of the environment with an efficient roadmap extraction method, to guide the robot navigation and to classify the different regions of space in which the robot moves. The paper presents the general reference architecture for the robotic system and then focuses on the algorithms for the construction of the roadmap, the classification of the regions of space and their use in robot navigation. Experimental results indicate the applicability and robustness of this approach in real situations. 相似文献
98.
99.
A key problem in time series prediction using autoregressive models is to fix the model order, namely the number of past samples
required to model the time series adequately. The estimation of the model order using cross-validation may be a long process.
In this paper, we investigate alternative methods to cross-validation, based on nonlinear dynamics methods, namely Grassberger–Procaccia,
Kégl, Levina–Bickel and False Nearest Neighbors algorithms. The experiments have been performed in two different ways. In
the first case, the model order has been used to carry out the prediction, performed by a SVM for regression on three real
data time series showing that nonlinear dynamics methods have performances very close to the cross-validation ones. In the
second case, we have tested the accuracy of nonlinear dynamics methods in predicting the known model order of synthetic time
series. In this case, most of the methods have yielded a correct estimate and when the estimate was not correct, the value
was very close to the real one. 相似文献
100.