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Joumana Farah Ralph Mounzer 《AEUE-International Journal of Electronics and Communications》2010,64(11):1046-1054
In this paper, we tackle the problem of motion estimation in video compression. Since Full Search Algorithms (FSA) present the disadvantage of adding a high computational burden to the encoder, fast search techniques have been used in conjunction with predictive filtering, in such a way to guarantee an acceptable quality with an affordable complexity. The aim of this work is to propose a novel framework for Kalman filtering of motion information in compressed video sequences. The merits of our new framework are twofold: First, using an appropriate formulation of the system equations, several shortcomings inherent with former models in the literature are greatly counteracted. Secondly, it is constructed using a generalized structure in such a way to enclose a large variety of prediction models. Therefore, it can adapt to different types of motion activities in video sequences, without the need for a different formulation in each prediction model, as was the case in previous studies. Furthermore, we propose an adaptive motion compensation technique that permits an additional improvement to the decoded video quality. Our framework permits a considerable gain in the average performance compared to previous models and even to the FSA technique. 相似文献
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Factors affecting polymer network organization were studied in highly crosslinked acrylics of the type used in dental adhesive resins. The variables tested were comonomer content and processing conditions. BisEMA (2,2,-bis[4-(2-methacryloyloxyethoxy)-phenyl]-propane) and BisEMA + TEGDMA (triethyleneglycol dimethacrylate) were cured with and without 25% comonomer. Comonomers had characteristics that are expected to influence intrachain organization in amorphous phases: TEGDMA, crosslinking; methyl methacrylate (MMA), monomer conversion; isobornyl methacrylate (IBM), low cure shrinkage; tetrahydrofurfuryl methacrylate (THFM), antiplasticization. Dynamic mechanical analysis temperature scans were run at 0.1 Hz 2h or 24h after ambient cure, or 24h postcure after heating at 75° or 125°C. After 24h, tan δ maxima occurred in ranges centering on approximately -30°, 75° and 150°C (Tg). Heating at 125°C nearly eliminated all peaks except Tg, reduced tan δ peaks and increased Tg by 0–14°. Tg increased in the order: TEGDMA>125°C>IBM>MMA>75°C>2h>24h>THFM. The ability to crosslink, and postcure heating at 125°C, were the more important factors found to increase intrachain organization in amine-promoted, unfilled BisEMA resins of the type used in dental sealants, luting cements and bulk-filling resin composite materials. 相似文献
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Tarter Ralph E.; Kirisci Levent; Kirillova Galina P.; Gavaler Judy; Giancola Peter; Vanyukov Michael M. 《Canadian Metallurgical Quarterly》2007,21(4):462
This investigation determined the influence of testosterone and neurobehavioral disinhibition (ND) on risk for substance use disorder (SUD). Testosterone level during puberty was hypothesized to promote social dominance associated with norm-violating behavior that, in turn, predisposes individuals to use of illicit drugs and, subsequently, SUD. Using a prospective paradigm, the authors recruited 179 boys (mean age=11.62 years, SD=0.88) and followed up when participants were ages 12-14, 16, 19, and 22. Results indicated that social dominance/norm-violating behavior (SD/NVB) at age 16 mediated the association between testosterone level (ages 12-14) and SUD (age 22). In addition, SD/NVB mediated the association between ND and SUD. These findings suggest that development of SUD is influenced by androgen-dependent and neurobehavioral processes via a social motivational style characterized by SD/NVB. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Akiya Kozawa Hidehiko Oho Mitsuru Sano Dorothy Brodd Ralph Brodd 《Journal of power sources》1999,80(1-2):12-16
Based on the previous success of adding ultra-fine carbon–PVA (polyvinyl alcohol) colloid solution to restore performance of weak batteries, a large scale test programme of practical batteries including those used in forklift, golf cart, taxi cab, truck and bus applications from 150 companies was carried out. More than 95% of the tested batteries exhibited excellent recovery in performance parameters including the specific gravity (S.G.), voltage and operation time (Ah capacity). The work reported here includes basic research studies to understand better the beneficial action of the carbon–PVA colloid additive. 相似文献
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