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41.
Video streaming over wireless networks is becoming increasingly important for a variety of applications. To accommodate the
dynamic change of wireless network bandwidths, Quality of Service (QoS) scalable video streams need to be provided. This paper
presents a system of content-adaptive streaming of instructional (lecture) videos over wireless networks for E-learning applications.
We first provide a real-time content analysis method to detect and extract content regions from instructional videos, then
apply a “leaking-video-buffer” model to adjust QoS of video streams dynamically based on video content. In content-adaptive
video streaming, an adaptive feedback control scheme is also developed to transmit properly compressed video streams to video
clients not only based on network bandwidth, but also based on video content and the preferences of users. Finally, we demonstrate
the scalability and content adaptiveness of the proposed video streaming system with experimental results on several instructional
videos. 相似文献
42.
BoyapatiM. Choudary NaiduS. Chowdari Karangula Jyothi Sateesh Madhi MannepalliL. Kantam 《Advanced Synthesis \u0026amp; Catalysis》2002,344(5):503-506
A triple catalytic system designed for asymmetric dihydroxylation of olefins, composed of NMM and two divergent heterogeneous catalysts, titanium silicalite and silica gel‐supported 1,4‐bis(9‐O‐dihydroquinidinyl)phthalazine [SGS‐(DHQD)2PHAL)]‐OsO4 complex relays the transport of two electrons from olefin to H2O2 used as a terminal oxidant to provide chiral diols with good yields and high enantiomeric excesses in a single pot. 相似文献
43.
The estA gene encoding the enzyme that catalyzes the production of (R)-beta-acetylmercaptoisobutyric acid from (R,S)-ester from Pseudomonas aeruginosa 1001, was cloned in Escherichia coli and its nucleotide sequence was determined, revealing the presumed open reading frame encoding a polypeptide of 316 amino acid residues (948 nucleotides). The overall A + T and C + G compositions were 32.59% and 67.41%, respectively. The amino acid sequence of the estA gene product showed a significant similarity with that of the triacylglycerol lipase from Psychrobacter immobilis (38% identity), triacylglycerol lipase from Moraxella sp. (36% identity), and two forms of carboxyl esterases from Acinetobacter calcoaceticus (17% and 17% identities). The deduced amino acid sequences have a pentapeptide consensus sequence, G-X-S-X-G, having an active serine residue, and another active site, dipeptides H-G, located at 70-100 amino acids upstream of the G-X-S-X-G consensus sequence. 相似文献
44.
Je-Hyuk Lee Gokul Boyapati Ki-Bang Song Sang-Ki Rhee Chul-Ho Kim 《Journal of Bioscience and Bioengineering》2000,90(6):684
The estA gene encoding the enzyme that catalyzes the production of (R)-β-acetylmercaptoisobutyric acid from (R,S)-ester from Pseudomonas aeruginosa 1001, was cloned in Escherichia coli and its nucleotide sequence was determined, revealing the presumed open reading frame encoding a polypeptide of 316 amino acid residues (948 nucleotides). The overall A+T and C+G compositions were 32.59% and 67.41%, respectively. The amino acid sequence of the estA gene product showed a significant similarity with that of the triacylglycerol lipase from Psychrobacter immobilis (38% identity), triacylglycerol lipase from Moraxella sp. (36% identity), and two forms of carboxyl esterases from Acinetobacter calcoaceticus (17% and 17% identities). The deduced amino acid sequences have a pentapeptide consensus sequence, G-X-S-X-G, having an active serine residue, and another active site, dipeptides H-G, located at 70–100 amino acids upstream of the G-X-S-X-G consensus sequence. 相似文献
45.
Asymmetric oxidation of sulfides to sulfoxides by chiral titanium pillared montmorillonite catalyst 总被引:1,自引:0,他引:1
Several sulfoxides with high enantiomeric purity have been synthesised using heterogeneous catalytic systems. A variety of titanium catalysts supported on Al2O3, SiO2, ZrO2 and montmorillonite, pillared clay catalysts using montmorillonite obtained from different sources and various chiral auxiliaries in presence of stoichiometric amounts of tertiary butyl hydroperoxide (TBHP) have been evaluated in asymmetric oxidation of prochiral sulfides to sulfoxides. It was found that Ti-PILC using montmorillonite K10 afforded optimum results. A probable active species responsible for high enantioselectivity is also discussed.IICT communication No. 3189. 相似文献
46.
Zexuan Zhu Yew-Soon Ong Manoranjan Dash 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》2007,37(1):70-76
This correspondence presents a novel hybrid wrapper and filter feature selection algorithm for a classification problem using a memetic framework. It incorporates a filter ranking method in the traditional genetic algorithm to improve classification performance and accelerate the search in identifying the core feature subsets. Particularly, the method adds or deletes a feature from a candidate feature subset based on the univariate feature ranking information. This empirical study on commonly used data sets from the University of California, Irvine repository and microarray data sets shows that the proposed method outperforms existing methods in terms of classification accuracy, number of selected features, and computational efficiency. Furthermore, we investigate several major issues of memetic algorithm (MA) to identify a good balance between local search and genetic search so as to maximize search quality and efficiency in the hybrid filter and wrapper MA. 相似文献
47.
Ikegami Aiko; Olsen Christopher M.; D'Souza Manoranjan S.; Duvauchelle Christine L. 《Canadian Metallurgical Quarterly》2007,121(2):389
Experiments were performed to examine the effects of cocaine self-administration and conditioning experience on operant behavior, locomotor activity, and nucleus accumbens (NAcc) and prefrontal cortex (PFC) dopamine (DA) responses. Sensory cues were paired with alternating cocaine and nonreinforcement during 12 (limited training) or 40 (long-term training) daily operant sessions. After limited training, NAcc DA responses to cocaine were significantly enhanced in the presence of cocaine-associated cues compared with nonreward cues and significantly depressed after cocaine-paired cues accompanied a nonreinforced lever response. PFC DA levels were generally nonresponsive to cues after the same training duration. However, after long-term training, cocaine-associated cues increased the magnitude of cocaine-stimulated PFC DA levels significantly over levels observed with nonreinforcement cues. Conversely, conditioned cues no longer influenced NAcc DA levels after long-term training. In addition, cocaine-stimulated locomotor activity was enhanced by cocaine-paired cues after long-term, but not after limited, training. Findings demonstrate that cue-induced cocaine expectation exerts a significant impact on dopaminergic and behavioral systems, progressing from mesolimbic to mesocortical regions and from latent to patent behaviors as cocaine and associative experiences escalate. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
48.
M. Lakshmi Kantam Y. Haritha N. Mahender Reddy B.M. Choudary F. Figueras 《Catalysis Letters》2003,90(3-4):231-231
49.
U. V. Choudary K. A. Gingerich L. R. Cornwell 《Metallurgical and Materials Transactions A》1977,8(9):1487-1491
From the Kundsen cell mass-spectrometric investigation of Pd-rich liquid alloys of Ti, the Gibbs energies of formation of
TiPd and TiPd3 at 1873 K have been derived as -67 ± 8 and -56 ± 8 kj/g atom, respectively. The corresponding enthalpies of
formation at 298 K are estimated to be -80 ± 10 and -70 ± kjJg atom. The stabilities of some Ti-X systems, with X = Fe, Ni,
Pd and Pt, are compared and correlated with the extent of electron transfer which is consistent with the Engel-Brewer concepts
of alloying behavior in transition metals.
Formerly with Texas A & M University. 相似文献
50.
Video streaming over wireless networks is becoming increasingly important for a variety of applications. To accommodate the
dynamic change of wireless network bandwidths, Quality of Service (QoS) scalable video streams need to be provided. This paper
presents a system of content-adaptive streaming of instructional (lecture) videos over wireless networks for E-learning applications.
We first provide a real-time content analysis method to detect and extract content regions from instructional videos, then
apply a “leaking-video-buffer” model to adjust QoS of video streams dynamically based on video content. In content-adaptive
video streaming, an adaptive feedback control scheme is also developed to transmit properly compressed video streams to video
clients not only based on network bandwidth, but also based on video content and the preferences of users. Finally, we demonstrate
the scalability and content adaptiveness of the proposed video streaming system with experimental results on several instructional
videos. 相似文献