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Wireless Networks - Nowadays, the smart grid has demonstrated a great ability to make life easier and more comfortable given recent advances. This paper studies the above issue from the perspective...  相似文献   
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Glass with compositions xK2O-(30 ? x)Li2O-10WO3-60B2O3 for 0 ≤ x ≤ 30 mol.% have been prepared using the normal melt quenching technique. The optical reflection and absorption spectra were recorded at room temperature in the wavelength range 300–800 nm. From the absorption edge studies, the values of the optical band gap (E opt) and Urbach energy (ΔE) have been evaluated. The values of E opt and ΔE vary non-linearly with composition parameter, showing the mixed alkali effect. The dispersion of the refractive index is discussed in terms of the single oscillator Wemple Di-Domenico model.  相似文献   
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The ubiquitous adoption of WiFi introduces large diversity in types of application requirements and topological characteristics. Consequently, considerable attention is being devoted to making WiFi networks controllable without compromising their scalability. However, the main MAC protocol of WiFi, distributed coordination function (DCF), is a contention-based protocol using random backoff. Thus, operating under DCF, the access of channel is hard to control and nonpredictable. In order to provide controllability of channel access in WiFi, we propose Rhythm, a MAC protocol that achieves scheduled WiFi efficiently using distributed contention. By achieving scheduled WiFi, channel access can be controlled by manipulating the schedule decision. We evaluate the performance of Rhythm through analysis, experiments, and case-studies.  相似文献   
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The TFRC protocol has been proposed as a TCP‐friendly protocol to transport streaming media over the Internet. However, its deployment is still questionable because it has not been compared to other important protocols, analysed in the presence of important mechanisms, such as the explicit congestion notification (ECN), and studied under more realistic network conditions. In this paper, we address these three aspects, including other congestion control protocols not considered before in the same investigation, such as TCP Tahoe, Reno, Newreno, Vegas, Sack, GAIMD, and the Binomial algorithms, the effect of using ECN in the friendliness of the protocols, and the fairness of the protocols under static and dynamic network conditions. We found that TFRC can be safely deployed in the Internet if competing with TCP Tahoe, New Reno and SACK since fairness is achieved under all scenarios considered. We also found that ECN actually helps in achieving better fairness. However, fairness problems arise when TFRC competes with TCP Reno, GAIMD, SQRT or IIAD in static or dynamic conditions, or both. We used normalized throughput, fairness index, and convergence time as the main performance metrics for comparison. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
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A study was conducted to determine the most suitable lactic culture combinations and the techniques for the preparation of low moisture part skim (LMPS) mozzarella cheese (pizza cheese) with a low level of galactose. The cheesemaking time tested for all 12 culture combinations was less than 3 h and hence was found suitable for pizza cheesemaking. The initial accumulated galactose concentration was lower in unstretched curd followed by no-brine curd and stretched curd in ascending order. During storage of the cheese for 7 days, the galactose percentage in the cheeses prepared using cultures comprising galactose-fermenting strains of Lactobacillus helveticus and Streptococcus thermophilus was 0.30 in stretched curd, 0.04 in unstretched curd and 0.03 in no-brine curd. The degree of reduction in the level of galactose in pizza cheese during storage was maximum with the no-brine curd technique followed by the unstretched and stretched curd techniques in that order. This study provides information regarding selection of starter culture combinations and techniques for pizza cheesemaking based on consumer preference for low or moderate browning mozzarella cheese as a result of its galactose concentration.  相似文献   
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Phytosterols (PS) from nine samples of olive oil from Olea europaea L., the Carolea, Cassanese and Coratina mono-cultivars, have been analyzed by gas chromatography. Coratina virgin olive oil (VOO) from the month of November showed highest contents of β-sitosterol (5491 mg kg−1) and Δ5 avenasterol (1767 mg kg−1). Olive pomace oil had the lowest total content of all PS, when compared to VOO. These results suggests that, PS can be an important regulatory factor for the functional quality of olive oil along the agro-industry chain from the orchard to nutraceutical.  相似文献   
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After earlier promising results for the control of anthracnose in avocado fruit by thyme vapours, our studies were extended to commercial use in tray packs. The effect of thyme oil low-density polyethylene impregnated pellets (TO-LDPE-P) in polylactic acid (PLA) sachets was investigated for the control of anthracnose and retention of dietary phytochemicals, fatty acid composition, D-mannoheptulose sugar and fruit quality in ready-to-eat avocado fruit. The 10% TO-LDPE-P significantly reduced the incidence severity of anthracnose and enabled the retention of dietary phytochemicals (p-coumaric, ferulic and caffeic acid, catechin and epicatechin), fatty acids, mannoheptulose, fruit firmness and taste compared to the currently used prochloraz® fungicide treatment. The results of this study strongly suggest the incorporation of 10% TO-LDPE-P in PLA sachets in commercial avocado tray packs as a natural option to improve fruit health, dietary phytochemicals, fatty acid composition and consumer satisfaction.  相似文献   
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