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1.
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   
2.
High planting density has been used to increase coffee production but there are few studies related to the variations it provokes in metabolite compositions. The use of 1H NMR data associated with chemometric techniques allows the determination of metabolic fingerprints and verification of metabolic changes when coffee is subjected to high planting densities. The aim of this work is to investigate 1H NMR spectral data of green bean extracts of Coffea arabica cv. IAPAR 59 grown in a square pattern at two planting densities, 6000 and 10,000 plants ha?1. Thirty extracts were obtained using a simplex centroid design with four solvents (ethanol, acetone, dichloromethane, and hexane). The lyophilized extracts were dissolved in DMSO-d6 to obtain the 1H NMR spectra. The spectral data were analyzed with principal component (PCA) and cluster analyses (CA). Significant differences between ethanolic and non-ethanolic extracts were found by PCA. Only the ethanolic mean spectrum showed characteristic chemical shifts of sugars and trigonelline. Acetone extracts were separated by cluster analysis.  相似文献   
3.
This paper provides a parallel review of two important issues for the next‐generation multimedia networking. Firstly, the emerging multimedia applications require a fresh approach to congestion control in the Internet. Currently, congestion control is performed by TCP; it is optimised for data traffic flows, which are inherently elastic. Audio and video traffic do not find the sudden rate fluctuations imposed by the TCP multiplicative‐decrease control algorithm optimal. The second important issue is the mobility support for multimedia applications. Wireless networks are characterized by a substantial packet loss due to the imperfection of the radio medium. This increased packet loss disturbs the foundation of TCP's loss‐based congestion control. This paper contributes to the ongoing discussion about the Internet congestion control by providing a parallel analysis of these two issues. The paper describes the main challenges, design guidelines, and existing proposals for the Internet congestion control, optimised for the multimedia traffic in the wireless network environment. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
4.
Wireless Networks - Coordination is foreseen to be an important component of future mobile radio networks. It is especially relevant in heterogeneous networks, where high power base stations...  相似文献   
5.
Nickel was sputter deposited on a glass with a thin film thickness of 600 nm under either in an argon atmosphere or under a partial pressure of nitrogen of either 1.3 x 10(-4) or 4 x 10(-4) mbar. Atomic force microscopy and scanning surface potential microscopy (SSPM) were used to study the morphology and to estimate the surface resistivity of the obtained Ni thin films taking into account surface-roughness effects. For the three samples investigated, the surface resistivity values as estimated using SSPM were in good agreement with the results obtained by standard four-point probe measurements.  相似文献   
6.
Hydrogen is considered to be the most promising candidate as a future energy carrier. One of the most used technologies for the electrolytic hydrogen production is alkaline water electrolysis. Electrode materials used in alkaline water electrolysis are mainly made from Ni or Ni-based alloys due to their desirable mechanical and chemical stability in hot and alkaline solution. Considerable research effort has been conducted on enhancement of electrocatalytic activity of Ni electrodes.  相似文献   
7.
Myotonic dystrophy type 1 (DM1) is one of the most variable monogenic diseases at phenotypic, genetic, and epigenetic level. The disease is multi-systemic with the age at onset ranging from birth to late age. The underlying mutation is an unstable expansion of CTG repeats in the DMPK gene, varying in size from 50 to >1000 repeats. Generally, large expansions are associated with an earlier age at onset. Additionally, the most severe, congenital DM1 form is typically associated with local DNA methylation. Genetic variability of DM1 mutation is further increased by its structural variations due to presence of other repeats (e.g., CCG, CTC, CAG). These variant repeats or repeat interruptions seem to confer an additional level of epigenetic variability since local DNA methylation is frequently associated with variant CCG repeats independently of the expansion size. The effect of repeat interruptions on DM1 molecular pathogenesis is not investigated enough. Studies on patients indicate their stabilizing effect on DMPK expansions because no congenital cases were described in patients with repeat interruptions, and the age at onset is frequently later than expected. Here, we review the clinical relevance of repeat interruptions in DM1 and genetic and epigenetic characteristics of interrupted DMPK expansions based on patient studies.  相似文献   
8.
The existence of a potential primary central nervous system lymphoma-specific genomic signature that differs from the systemic form of diffuse large B cell lymphoma (DLBCL) has been suggested, but is still controversial. We investigated 19 patients with primary DLBCL of central nervous system (DLBCL CNS) using the TruSeq Amplicon Cancer Panel (TSACP) for 48 cancer-related genes. Next generation sequencing (NGS) analyses have revealed that over 80% of potentially protein-changing mutations were located in eight genes (CTNNB1, PIK3CA, PTEN, ATM, KRAS, PTPN11, TP53 and JAK3), pointing to the potential role of these genes in lymphomagenesis. TP53 was the only gene harboring mutations in all 19 patients. In addition, the presence of mutated TP53 and ATM genes correlated with a higher total number of mutations in other analyzed genes. Furthermore, the presence of mutated ATM correlated with poorer event-free survival (EFS) (p = 0.036). The presence of the mutated SMO gene correlated with earlier disease relapse (p = 0.023), inferior event-free survival (p = 0.011) and overall survival (OS) (p = 0.017), while mutations in the PTEN gene were associated with inferior OS (p = 0.048). Our findings suggest that the TP53 and ATM genes could be involved in the molecular pathophysiology of primary DLBCL CNS, whereas mutations in the PTEN and SMO genes could affect survival regardless of the initial treatment approach.  相似文献   
9.
Platinum is deposited spontaneously on Au(1 1 1) surface from 1 mM H2PtCl6 + 1 M HClO4 solution using multiple deposition procedure. X-ray photoelectron spectroscopy (XPS) analysis has shown that after immersion into the Pt containing solution and rinsing with water, Pt(OH)2 resides on the Au(1 1 1) substrate. Consecutive depositions as well as in situ scanning tunneling microscopy (STM) and electrochemical measurements are performed on previously electrochemically reduced Pt/Au(1 1 1) surfaces. Only homogeneous distribution of thus deposited Pt islands is observed by in situ STM. With subsequent depositions, the width of deposited Pt islands increases, but stays lower than 10 nm, while a significant increase of Pt islands height is observed, leading to moderate increase of the coverage. Cyclic voltammetry (CV) profiles of obtained Pt/Au(1 1 1) surfaces, and CO stripping curves are recorded in 0.5 M H2SO4 solution. CO oxidation takes place only at higher potentials shifting negatively with increasing coverage. This is discussed with respect to Pt islands width and height distributions and to the influence of the Au(1 1 1) substrate surface.  相似文献   
10.
Wireless Personal Communications - In orthogonal frequency division multiple access networks buffer aided non-transparent in-band half duplex decode and forward relay nodes aim to improve coverage...  相似文献   
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