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111.
Christian Überall Christopher Köhnen Veselin Rakocevic Rudolf Jäger Erich Hoy Muttukrishnan Rajarajan 《Multimedia Tools and Applications》2013,62(3):785-820
This paper presents novel algorithms which are able to generate recommendations within a heterogeneous service environment. In this work explicitly set preferences as well as implicitly logged viewing behavior are employed to generate recommendations for Digital Video Broadcast (DVB) content. This paper also discusses the similarity between the DVB genres and YouTube categories. In addition it presents results to show the comparison between well known collaborative filtering methods. The outcome of this comparison study is used to identify the most suitable filtering method to use in the proposed environment. Finally the paper presents a novel Personal Program Guide (PPG), which is used as a tool to visualize the generated recommendations within a heterogeneous service environment. This PPG is also capable of showing the linear DVB content and the non-linear YouTube videos in a single view. 相似文献
112.
Shahram Minaei Oguzhan ÇiÇekoglu Hakan Kuntman Sait TÜrkÖz 《International Journal of Electronics》2013,100(8):915-922
Three new current-mode second-order filter configurations which employ one or two current controlled conveyors (CCCIIs) and three passive elements are presented. Each proposed filter can realize one of the bandpass, lowpass or highpass responses all at high impedance outputs. The proposed filters offer current-control of pole angular frequency ωo without disturbing the parameter ωo /Q. No component matching is required and all the passive and active sensitivities are low. PSPICE simulation results are given to confirm the theoretical analysis. 相似文献
113.
A contour diagram approach is presented for the identification of surface ozone concentration feature based on a set of rules by considering the meteorological variables such as the solar radiation, wind speed, temperature, humidity and rainfall. A fuzzy rule system approach is used because of the imprecise, insufficient, ambiguous and uncertain data available. The contour diagrams help to identify qualitative ozone concentration variability rules which are more general than conventional statistical or time series analysis. In the methodology, ozone concentration contours are based on a fixed variable as ozone precursor, namely, NOx and as the third variable one of the meteorological factors. Such contour diagrams for ozone concentration variation are prepared for six months. It is possible to identify the maximum ozone concentration episodes from these diagrams and then to set up the valid rules in the form of IF-THEN logical statements. These rules are obtained from available daily ozone, NOx and meteorological data as a first approximate reasoning step. In this manner, without mathematical formulations, expert maximum ozone concentration systems are identified. The application of the contour diagram approach is performed for daily ozone concentration measurements on European side of Istanbul city. It is concluded that through approximate reasoning with fuzzy rules, the maximum ozone concentration episodes can be identified and predicted without any mathematical expression. 相似文献
114.
Modifying of Cotton Fabric Surface with Nano-ZnO Multilayer Films by Layer-by-Layer Deposition Method 总被引:1,自引:0,他引:1
Şule S Uğur Merih Sarıışık A Hakan Aktaş M Çiğdem Uçar Emre Erden 《Nanoscale research letters》2010,5(7):1204-1210
ZnO nanoparticle–based multilayer nanocomposite films were fabricated on cationized woven cotton fabrics via layer-by-layer
molecular self-assembly technique. For cationic surface charge, cotton fabrics were pretreated with 2,3-epoxypropyltrimethylammonium
chloride (EP3MAC) by pad-batch method. XPS and SEM were used to examine the deposited nano-ZnO multilayer films on the cotton
fabrics. The nano-ZnO films deposited on cotton fabrics exhibited excellent antimicrobial activity against Staphylococcus aureus bacteria. The results also showed that the coated fabrics with nano-ZnO multilayer films enhanced the protection of cotton
fabrics from UV radiation. Physical tests (tensile strength of weft and warp yarns, air permeability and whiteness values)
were performed on the fabrics before and after the treatment with ZnO nanoparticles to evaluate the effect of layer-by-layer
(LbL) process on cotton fabrics properties. 相似文献
115.
Nilay Bereli Gülsu Şener Handan Yavuz Adil Denizli 《Materials science & engineering. C, Materials for biological applications》2011,31(5):1078-1083
Low density lipoprotein (LDL) cholesterol is a major ingredient of the plaque that collects in the coronary arteries and causes coronary heart diseases. Among the methods used for the extracorporeal elimination of LDL from intravasal volume, immunoaffinity technique using anti-LDL antibody as a ligand offers superior selectivity and specificity. Proper orientation of the immobilized antibody is the main issue in immunoaffinity techniques. In this study, anti-human β-lipoprotein antibody (anti-LDL antibody) molecules were immobilized and oriented through protein A onto poly(2-hydroxyethyl methacrylate) (PHEMA) cryogel in order to remove LDL from hypercholesterolemic human plasma. PHEMA cryogel was prepared by free radical polymerization initiated with N,N,N′,N′-tetramethylene diamine (TEMED). PHEMA cryogel with a swelling degree of 8.89 g H2O/g and 67% macro-porosity was characterized by swelling studies, scanning electron microscope (SEM) and blood compatibility tests. All the clotting times were increased when compared with control plasma. The maximum immobilized anti-LDL antibody amount was 63.2 mg/g in the case of random antibody immobilization and 19.6 mg/g in the case of oriented antibody immobilization (protein A loading was 57.0 mg/g). Random and oriented anti-LDL antibody immobilized PHEMA cryogels adsorbed 111 and 129 mg LDL/g cryogel from hypercholesterolemic human plasma, respectively. Up to 80% of the adsorbed LDL was desorbed. The adsorption–desorption cycle was repeated 6 times using the same cryogel. There was no significant loss of LDL adsorption capacity. 相似文献
116.
Yay?k butter, made from yoghurt, is one of the traditional dairy products in Anatolia In this study, some properties of Yay?k butter produced from cow, sheep, and goat yoghurts have been observed during 30 days of storage at 4–5 °C. In this purpose yoghurts were produced from different species milks then these yoghurts were used as a raw material for production of Yay?k butters samples. On the first day of the storage, differences in pH of serum among the butter produced from different mammals were statistically significant. The highest value of lactic acid was measured in the sample of sheep butter (SB). The level of lactic acid in Yay?k butters was significantly different. Goat butter (GB) had weaker oxidative stability and significantly higher peroxide value than those of other samples. The highest accumulation of the free fatty acids has been detected in sample GB. All samples of Yay?k butter received almost the same score on the first day of the storage, but on day 30 some flavour defects in sample GB were noted by the panelists. 相似文献
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118.
Polymeric nanocomposites were synthesized from functionalized soybean‐oil‐based polymer matrix and montmorillonite (MMT) clay using an in situ free radical polymerization reaction. Acrylated epoxidized soybean oil combined with styrene was used as the monomer. Organophilic MMT (OrgMMT) was obtained using a quaternized derivative of methyl oleate, which was synthesized from olive oil triglyceride, as a renewable intercalant. The resultant nanocomposites were characterized using X‐ray diffraction and atomic force microscopy. The effect of increased nanofiller loading on the thermal and mechanical properties of the nanocomposites was investigated using thermogravimetric analysis and dynamic mechanical analysis. It was found that the desired exfoliated nanocomposite structure was achieved when the OrgMMT loading was 1 and 2 wt%, whereas a partially exfoliated or intercalated nanocomposite was obtained for 3 wt% loading. All the nanocomposites were found to have improved thermal and mechanical properties as compared with virgin acrylated epoxidized soybean‐oil‐based polymer matrix. The nanocomposite containing 2 wt% OrgMMT clay was found to have the highest thermal stability and best dynamic mechanical performance. Copyright © 2010 Society of Chemical Industry 相似文献
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