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排序方式: 共有652条查询结果,搜索用时 15 毫秒
1.
Castro Mateus B. Souza Raphael R. N. Junior Agord M. P. Lima Eduardo R. Manera Leandro T. 《Analog Integrated Circuits and Signal Processing》2021,109(3):647-656
Analog Integrated Circuits and Signal Processing - This paper presents the complete design of a phase locked loop-based clock synthesizer for reconfigurable analog-to-digital converters. The... 相似文献
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3.
Tsuchiya Letícia Diniz Braga Lucas Fiorini de Faria Oliveira Otávio de Bettio Raphael Winckler Greghi Juliana Galvani Freire André Pimenta 《Personal and Ubiquitous Computing》2021,25(2):281-295
Personal and Ubiquitous Computing - This article presents a study concerning the evaluation of a smart home control system for elderly people with a sample of 10 users in a city in the interior of... 相似文献
4.
Abd Essalam Badoud Farid Merahi Belkacem Ould Bouamama Saad Mekhilef 《International Journal of Hydrogen Energy》2021,46(47):24011-24027
This work presents a complete bond graph modeling of a hybrid photovoltaic-fuel cell-electrolyzer-battery system. These are multi-physics models that will take into account the influence of temperature on the electrochemical parameters. A bond graph modeling of the electrical dynamics of each source will be introduced. The bond graph models were developed to highlight the multi-physics aspect describing the interaction between hydraulic, thermal, electrochemical, thermodynamic, and electrical fields. This will involve using the most generic modeling approach possible for managing the energy flows of the system while taking into account the viability of the system. Another point treated in this work is to propose. In this work, a new strategy for the power flow management of the studied system has been proposed. This strategy aims to improve the overall efficiency of the studied system by optimizing the decisions made when starting and stopping the fuel cell and the electrolyzer. It was verified that the simulation results of the proposed system, when compared to simulation results presented in the literature, that the hydrogen demand is increased by an average of 8%. The developed management algorithm allows reducing the fuel cell degradation by 87% and the electrolyzer degradation by 65%. As for the operating time of the electrolyzer, an increment of 65% was achieved, thus improving the quality of the produced hydrogen. The Fuel Cell's running time has been decreased by 59%. With the ambition to validate the models proposed and the associated commands, the development of this study gave rise to the creation of an experimental platform. Using this high-performance experimental platform, experimental tests were carried out and the results obtained are compared with those obtained by simulation under the same metrological conditions. 相似文献
5.
Platelet aggregation is known to be inhibited by ethanol, and this has been suggested to be one of the attenuating effects
of ethanol in cardiovascular disease. Recent studies have implicated an inhibition of phospholipase A2 induced arachidonic acid release, since the production of prostanoids that are formed from arachidonic acid and are involved
in the aggregation process has been shown to be diminished by ethanol. Phospholipase A2 is found in platelets in both a cytosolic form, from where it may translocate to the plasma membrane to release arachidonic
acid, and in a secretory form which is released extracellularly upon activition. In the present study, the effect of ethanol
on the secretion of phospholipase A2 and on its activity was determined. It was found that ethanol inhibited trast, the activity of the cytosolic form of phospholipase
A2 was inhibited by ethanol. 相似文献
6.
The reticular lamina creates an ion barrier, withstands mechanical stress in the organ of Corti and is able to maintain its integrity during and after severe hair cell loss. Tight junctions maintain the ionic gradient whereas adherens junctions and the cytoskeleton are responsible for the integrity and mechanical resistance of tissues. In this study we used immunofluorescence and electron microscopy to examine the distribution of proteins of tight junctions (cingulin), adherens junctions (E-cadherin, alpha- and beta-catenin) and the cytoskeleton (actin, cytokeratin and tubulin) in whole-mounts of the normal and ototoxically damaged organ of Corti. In normal ears the proteins of adherens junctions were found in all cell types of the reticular lamina. We now demonstrate that all cells forming the reticular lamina partially overlap each other organizing extensive cell contacts with a complex three-dimensional shape. During scar formation, the tight junctions as well as adherens junctions between hair and supporting cells appeared in two distinct focal planes, which could help to preserve the ionic barrier and tissue integrity during hair cell degeneration. During scar formation all cytoskeletal structures in the reticular lamina were reorganized in a specific spatio-temporal pattern. We present a three-dimensional model of cell contact organization in the reticular lamina of normal ears and during scar formation. 相似文献
7.
Raphael M. Munavu 《Journal of the American Oil Chemists' Society》1983,60(9):1653-1653
Seed kernels ofCalodendrum capense (L.f.) Thunb. yielded 60% of a light yellow oil which had the following fatty acid composition: 23.8% palmitic, 4.5% stearic,
33.7% oleic, 35.6% linoleic, 1.4% linolenic and 1.0% arachidic. Myristic and behenic acids were present in trace amounts,
and the kernel cake contained 37.6% crude protein. 相似文献
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9.
Dragomir B. Bukur Snehal A. Patel Raphael Matheo 《Chemical Engineering Communications》1987,60(1):63-78
Gas hold-up and Sauter mean bubble diameter measurements were made in a 0.051 m diameter by 3 m long glass bubble column in the system, nitrogen-molten wax, with three different waxes (paraffin wax FT-300, Sasol's Arge wax and Mobil's reactor wax). Paraffin wax has a tendency to foam and gas hold-up is a strong function of gas distributor type, temperature and start-up procedure, whereas the reactor waxes do not foam and are much less affected by these variables, In experiments at 265°C with a 1.85 mm single hole orifice plate distributor the gas hold-ups were nearly the same for all three waxes. However, significant differences in Sauter mean bubble diameters were obtained in experiments with different waxes; FT-300 wax produced the smallest Sauter mean bubble diameters whereas Mobil's reactor wax produced the largest bubbles. Addition of 1-octadecanol and octadecanoic acid (up to 10wt%) to the FT-300 paraffin wax caused an increase in gas hold-up and a delay in the foam break-up in runs at 265°C with the 1.85 mm orifice plate distributor. 相似文献
10.
目的 基于非下采样Contourlet变换(NSCT)融合策略可以有效地抑制背景信息增强变化区域的信息。但是融合后图像具有复杂的统计特征,传统的基于统计特征的变化检测难以实现。基于参数化内核图割的遥感图像分割不受统计特征的限制。为此提出了一种基于NSCT融合和参数化内核图割的SAR图像无监督水灾变化检测新算法。方法 将均值比差异图像和对数比差异图像采用基于NSCT的融合算法进行融合,将融合后的差异图像采用参数化内核图割算法进行前景/背景的分割,得到最终的变化检测结果。结果 融合后的差异图像利用前两种差异图像的互补信息提高了变化检测精度。算法不受统计模型限制,不需要先验知识,适用性强。结论 实验结果表明,本文算法的检测精度优于传统的变化检测方法。 相似文献