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71.
S. Sedef Savas C. Göktuğ Gürler A. Murat Tekalp Erhan Ekmekcioglu Stewart Worrall Ahmet Kondoz 《Signal Processing: Image Communication》2012,27(5):522-531
In this paper, we propose a novel solution for the adaptive streaming of 3D representations in the form of multi-view video by utilizing P2P overlay networks to assist the media delivery and minimize the bandwidth requirement at the server side. Adaptation to diverse network conditions is performed regarding the features of human perception to maximize the perceived 3D. We have performed subjective tests to characterize these features and determined the best adaptation method to achieve the highest possible perceived quality. Moreover, we provide a novel method for mapping from scalable video elementary stream to torrent-like data chunks for adaptive video streaming and provide an optimized windowing mechanism that ensures timely delivery of the content over yanl?? gibi. The paper also describes techniques generating scalable video chunks and methods for determining system parameters such as chunk size and window length. 相似文献
72.
Effects of Er:YAG laser on bond strength of self‐etching adhesives to caries‐affected dentin 下载免费PDF全文
Alp Erdin Koyuturk Bilal Ozmen Murat Cortcu Ugur Tokay Gul Tosun Mustafa Erhan Sari 《Microscopy research and technique》2014,77(4):282-288
The erbium:yttrium–aluminum–garnet (Er:YAG) laser may be effective the bond strength of adhesive systems on dentine surfaces, the chemical composition and aggressiveness of adhesive systems in clinical practice. The purpose of this study was to evaluate the effects of the Er:YAG laser system with the bonding ability of two different self‐etching adhesives to caries‐affected dentine in primary molars. Ninety mid‐coronal flat dentine surfaces obtained from sound and caries‐affected human primary dentine were treated with an Er:YAG laser or a bur. The prepared surfaces were restored with an adhesive system (Xeno V; Clearfil S3) and a compomer (Dyract Extra). The restored teeth were sectioned with a low‐speed saw and 162 samples were obtained. The bond strength of the adhesive systems was tested using the micro‐tensile test method. The data were statistically analyzed. A restored tooth in each group was processed for scanning electron microscopy evaluation. The values of the highest bond strength were obtained from the Clearfil S3‐Er:YAG laser‐sound dentine group in all groups. (24.57 ± 7.27 MPa) (P > 0.05). The values of the lowest bond strength were obtained from the Xeno V‐Er:YAG laser‐sound dentine group in all groups (11.01 ± 3.89 MPa). It was determined that the Clearfil S3 increased the bond strength on the surface applied with Er:YAG laser according to the Xeno V. Microsc. Res. Tech. 77:282–288, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
73.
Dried fruits and nuts make up a significant portion of the commodities traded globally, and the presence of yeasts and molds on dried fruits and nuts can be a public health risk because of the potential for exposure to toxigenic fungi. Since current postharvest treatment technologies are rather limited for dried fruits and nuts, electron beam (E-beam) radiation experiments were performed to determine the doses required to reduce the yeast and mold bioburden of raisins, walnuts, and dates. The indigenous yeast and mold bioburden on a select number of commodities sold at retail ranged from 10(2) to 10(3) CFU/g. E-beam inactivation kinetics based on the linear model suggest that the decimal reduction dose required to eliminate 90% of the microbial population (D10-value) of these indigenous fungal populations ranges from 1.09 to 1.59 kGy. Some samples, however, exhibited inactivation kinetics that were better modeled by a quadratic model. The results indicate that different commodities can contain molds and yeasts of varying resistance to ionizing radiation. It is thus essential for the dried fruit and nut industry to determine empirically the minimum E-beam dose that is capable of reducing or eliminating the bioburden of yeasts and molds in their specific commodities. 相似文献
74.
Abstract We consider a change detection problem in which the arrival rate of a Poisson process changes suddenly at some unknown and unobservable disorder time. It is assumed that the prior distribution of the disorder time is known. The objective is to detect the disorder time with an online detection rule (a stopping time) in a way that balances the frequency of false alarms and detection delay. So far in the study of this problem, the prior distribution of the disorder time is taken to be exponential distribution for analytical tractability. Here, we will take the prior distribution to be a phase-type distribution, which is the distribution of the absorption time of a continuous time Markov chain with a finite state space. We find an optimal stopping rule for this general case. We illustrate our findings on two numerical examples. 相似文献
75.
Todd L. Kurth Brajendra K. Sharma Sevim Z. Erhan 《Chemical Engineering Communications》2013,200(8):1065-1077
The frictional behaviors of a variety of fatty alkenyl esters and their corresponding fatty epoxide esters (epoxy methyl oleate (EMO) and methyl oleate (MO), epoxy methyl linoleate (EMLO) and methyl linoleate (MLO), epoxy methyl linolenate (EMLEN) and methyl linolenate (MLEN)), epoxidized soybean oil (ESBO), and a commercial epoxidized 2-ethylhexyl transesterified soybean oil (VF) as additives in hexadecane have been examined in a boundary lubrication test regime using steel contacts. Langmuir critical additive concentrations were determined, which provide the following order of negative adsorption energies: ESBO > VF > EMO ≥ EMLO > EMLEN and MLEN ≥ MLO > MO. Thus, for the similar epoxidized materials the greater degree of epoxidation results in less negative calculated total adsorption energies; this trend is reversed for the olefinic parent systems. This ordering agrees with that obtained via a more complex unconstrained cooperative interaction adsorption model. Fits of the steady-state coefficient of friction (COF) versus concentration data indicate an inverse relation of the obtained interaction parameters (α) with the primary adsorption energies (E). These results demonstrate the complexity of the adsorption mechanism that occurs. 相似文献
76.
为了进一步研究蛋白质酶切后重新结合成同源二聚体时功能区域中残基的影响。本文选用硫氧还蛋白(TRX)和硫氧还蛋白变体(TRXL97F)酶切后得到的两组片段:N片段(1-72)和C片段(74-108)作为研究对象。比较排在79位的残基的改变对N片段(1-73)和C片段(74-108)作为研究对象。比较排在79位的残基的改变对N片段(1-73)和C片段(74-108)重新结合成同源二聚体的影响,得到以下结论:1.TRX中处于β折叠状态的βR区域(P76,T77,L78,L80,F81和K82)^5中残基由链变为芳香环使N片段和C片段重新聚合成非共价同源二聚体的速率常数有所减小。2.这一变化对形成的同源二聚体的稳定性影响不大。 相似文献
77.
An experimental study was conducted to investigate the effects of using binary, ternary, and quaternary cementitious blends
of portland cement (PC), fly ash (FA), ground granulated blast furnace slag (GBS), silica fume (SF), and metakaolin (MK) on
initial and final setting times of self-compacting concretes (SCCs). For this purpose, a total of 65 SCC mixtures were prepared
at two different water binder ratios. Furthermore, based on the experimental results, neural network (NN) model-based explicit
formulations were developed to predict the initial and final setting times of SCCs in terms of the amount of concrete constituents,
namely mixing water, PC, FA, GBS, SF, MK, fine (fa) and coarse (ca) aggregates, and superplasticizer (SP). The test results
have revealed that the mineral admixtures were very effective on the initial and final setting times of SCCs. Besides, it
was found that the model developed by using NN seemed to have a high prediction capability of initial and final setting times
of SCCs. 相似文献
78.
The boundary coefficient of friction (COF) of starch–oil composite dry film lubricants was investigated as a function of starch type (waxy vs. normal purified food grade corn starch), oil chemistry (hexadecane vs. oleic acid and various vegetable oils), and starch‐to‐oil ratio. Based on the results, a mechanism of starch–oil interaction in these composites was proposed. According to the proposed mechanism: (a) the oil in the composite is distributed between the bulk and the surface of the starch; and (b) the fraction of the oil trapped in the bulk and that adsorbed on the surface are related to each other by an equilibrium constant, and are functions of the total oil concentration in the composite. In line with the proposed mechanism, an adsorption model was used to quantify the free energy of adsorption (ΔGads) of the polar oils onto the starch surface. The analysis gave ΔGads values that were higher than those reported for the adsorption of the same polar oils onto steel surfaces. This result is consistent with the effect of the relative surface energies of steel and starch on the adsorption of polar oils. The adsorption property of the non‐polar hexadecane relative to the polar oils was estimated by comparing their interfacial tensions with starch. The result showed a higher interfacial tension for hexadecane–starch than that for the polar oil–starch composites. This result predicts a relatively poorer compatibility with, and, hence, poorer adsorption of hexadecane onto starch leading to higher COF, as was observed in the friction measurements. Published in 2006 by John Wiley & Sons, Ltd. 相似文献
79.
80.
New epoxidized soybean oil (ESO)/clay nanocomposites have been prepared with triethylenetetramine (TETA) as a curing agent. The dispersion of the clay layers is investigated by X-ray diffraction (XRD) and transmission electron microscopy (TEM). XRD and TEM data reveal the intercalated structure of ESO/clay nanocomposites has been developed. The thermogravimetric analysis exhibits that the ESO/clay nanocomposites are thermally stable at temperatures lower than 180 °C, with the maximum weight loss rate after 325 °C. The glass transition temperature, Tg, about 7.5 °C measured by differential scanning calorimetry (DSC) and Tg about 20 °C measured by dynamic mechanical study have been obtained. The difference in the Tg between DSC and dynamic measurements may be caused by different heating rate. The nanocomposites with 5-10 wt% clay content possess storage modulus ranging from 2.0×106 to 2.70×106 Pa at 30 °C. The Young's modulus (E) of these materials varies from 1.20 to 3.64 MPa with clay content ranging from 0 to 10 wt%. The ratio of epoxy (ESO) to hydrogen (amino group of TETA) greatly affects dynamic and tensile mechanical properties. At higher amount of TETA, the nanocomposites exhibit stronger tensile and dynamic properties. 相似文献