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21.
Leila Sharifi Llorenç Cerdà-Alabern Felix Freitag Luís Veiga 《Journal of Grid Computing》2016,14(2):299-325
The cost of power and its associated delivery are becoming significant factors in the total expenditure of large-scale data centers. Numerous techniques have been proposed to address the energy efficiency issue in cloud systems. Recently, some efforts have been made to decentralize the cloud via distributing data centers in diverse geographical positions, at different scales. In this paper, we elaborate on the energy effectiveness of service provisioning on different cloud architectures, from a mega-data center to a nano data center, which provides the extreme decentralization in terms of cloud architecture, as well as P2P-clouds or community network clouds. We study the energy consumption through an analytical and simulation framework for video streaming and MapReduce applications. 相似文献
22.
Emna B. Saafi‐Ben Salah Guido Flamini Amira El Arem Manel Issaoui Samia Dabbou Leila BenYahia Ali Ferchichi Mohamed Hammami Lotfi Achour 《International Journal of Food Science & Technology》2012,47(9):1903-1908
This paper reports a discrimination study based on the physico‐chemical characteristics, fatty acids and profile of volatile compounds of the seeds from seven date palm varieties (Phoenix dactylifera L.) grown in Tunisia. Date seeds contained 10.49–14.76% moisture; 6.28–11.2% fat (on a dry weight basis); 2.67–12.85% protein; 0.91–6.06% reducing sugar; 0.61–2.98% sucrose and 0.97–1.17% ash. Gas liquid chromatography revealed that the oil fraction of the date palm seeds contained eighteen fatty acids, with oleic acid (30.77–42.50%) and lauric acid (18.51–27.48%) as the main unsaturated and saturated ones. Volatile profile showed differences among varieties. In total, forty‐five compounds were identified, mainly alcohols, aldehydes and unsaturated hydrocarbons ones. This study provides evidence that the seeds of date may be a potential source of valuable nutrients with interesting functionality. 相似文献
23.
In this paper a novel low voltage (LV) very low power (VLP) class AB current output stage (COS) with extremely high linearity and high output impedance is presented. A novel current splitting method is used to minimize the transistors gate–source voltages providing LV operation and ultra high current drive capability. High linearity and very high output impedance are achieved employing a novel resistor based current mirror avoiding conventional cascode structures to be used. The operation of the proposed COS has been verified through HSPICE simulations based on TSMC 0.18 μm CMOS technology parameters. Under supply voltage of ±0.7 V and bias current of 5 μA, it can deliver output currents as high as 14 mA with THD better than ?53 dB and extremely high output impedance of 320 MΩ while consuming only 29 μW. This makes the proposed COS to have ultra large current drive ratio (Ioutmax/Ibias or the ratio of peak output current to the bias current of output branch transistors) of 2800. By increasing supply voltage to ±0.9 V, it can deliver extremely large output current of ±24 mA corresponding to 3200 current drive ratio while consuming only 42.9 μW and exhibiting high output impedance of 350 MΩ. Interestingly, the proposed COS is the first yet reported one with such extremely high output current and a THD even less than ?45 dB. Such ultra high current drive capability, high linearity and high output impedance make the proposed COS an outstanding choice for LV, VLP and high drive current mode circuits. The superiority of the proposed COS gets more significance by showing in this work that conventional COS can deliver only ±3.29 mA in equal condition. The proposed COS also exhibits high positive and negative power supply rejection ratio (PSRR+/PSRR?) of 125 dB and 130 dB, respectively. That makes it very suitable for LV, VLP mixed mode applications. The Monte Carlo simulation results are provided, which prove the outstanding robust performance of the proposed block versus process tolerances. Favorably the proposed COS resolves the major limitation of current output stages that so far has prevented designing high drive current mode circuits under low supply voltages. In brief, the deliberate combination of so many effective novel methods presents a wonderful phenomenal COS block to the world of science and engineering. 相似文献
24.
Effect of Mentha spicata L. and Mentha aquatica L. essential oils on the microbiological properties of fermented dairy product,kashk 下载免费PDF全文
Leila Golestan Laleh Seyedyousefi Hami Kaboosi Hamed Safari 《International Journal of Food Science & Technology》2016,51(3):581-587
The antibacterial activity of Mentha spicata and Mentha aquatica essential oils (EO) was tested against Staphylococcus aureus, Lactobacillus reuteri, Bifidobacterium animalis and Clostridium perfringens using agar well and disc diffusion techniques. Results showed that M. spicata EO had the highest inhibition activity against the studied microorganisms. Then, the antibacterial activity of both EO at 1500 and 2500 ppm was examined in industrial liquid kashk during the storage at 4 °C for 20 days. Both EO reduced the S. aureus viable count below 5 log CFU g?1 after 4 days; however, the population of C. perfringens, L. reuteri and B. animalis decreased <1 log CFU g?1 during the storage time. The least deteriorative effect on the lactic acid bacteria was related to M. aquatica. As revealed by organoleptic studies, kashk samples containing M. aquatica EO at 1500 and 2500 ppm were the most preferred samples. 相似文献
25.
Ghabi Jalel Dhouibi Hedi 《International Journal of Control, Automation and Systems》2018,16(3):1156-1164
International Journal of Control, Automation and Systems - In this paper, we propose a new sliding mode control for discrete time nonlinear uncertain systems. The uncertainties include both... 相似文献
26.
Hallal Nassim Yelles Chaouche Abdelkrim Hamai Lamine Lamali Atmane Dubois Laurent Mohammedi Yahia Hamidatou Mouloud Djadia Leila Abtout Abdeslam 《Bulletin of Engineering Geology and the Environment》2019,78(8):5653-5670
Bulletin of Engineering Geology and the Environment - A better understanding of the spatiotemporal evolution of landslides in urban zones is a key factor in assessing the risk of future slides... 相似文献
27.
28.
Elisangela F. Boffo Leila A. Tavares Antonio C.T. Tobias Márcia M.C. Ferreira Antonio G. Ferreira 《LWT》2012,49(1):55-63
The potential of NMR spectroscopy to differentiate honeys concerning to the nectar employed in its production was evaluated. The application of chemometric methods to 1H NMR spectra has allowed to discriminate the honeys produced in the state of São Paulo, being identified the signals of responsible substances for the discrimination. Application of PCA and HCA methods to 1H NMR data have resulted in the natural clustering of the samples. Wildflower honeys were characterized by higher concentration of phenylalanine and tyrosine. Citrus honeys showed higher amounts of sucrose than other compounds, while eucalyptus honeys had higher amount of lactic acid than the others. Assa-peixe honeys showed spectra similar to eucalyptus and citrus. Sugar-cane honeys showed some signals similar to eucalyptus and citrus honeys, but also showed the tyrosine and phenylalanine signals. Adulterated honeys showed 5-hydroxymethylfurfural, citric acid and ethanol signals. KNN, SIMCA and PLS-DA methods were used to build predictive models for honey classification. In the commercial honeys prediction KNN, SIMCA and PLS-DA models correctly classified 66.7; 22.2 and 72.2% of the samples, respectively. 相似文献
29.
Sorkhi Leila Hammell Joshua J. Crawford Grant A. 《Metallurgical and Materials Transactions A》2020,51(9):4390-4405
Metallurgical and Materials Transactions A - Additive manufacturing of magnesium (Mg) alloys has gained interest for the potential to fabricate complex geometries for extreme light-weighting or... 相似文献
30.
Rastegar Leila Montazer Majid Gaminian Hamdam 《Clean Technologies and Environmental Policy》2016,18(6):2019-2026
Clean Technologies and Environmental Policy - In this study, aminolysis of polyester fabric was carried out along with in situ synthesis of silver nanoparticles in a single-step processing at room... 相似文献