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121.
Stereo Matching with Transparency and Matting 总被引:2,自引:2,他引:0
This paper formulates and solves a new variant of the stereo correspondence problem: simultaneously recovering the disparities, true colors, and opacities of visible surface elements. This problem arises in newer applications of stereo reconstruction, such as view interpolation and the layering of real imagery with synthetic graphics for special effects and virtual studio applications. While this problem is intrinsically more difficult than traditional stereo correspondence, where only the disparities are being recovered, it provides a principled way of dealing with commonly occurring problems such as occlusions and the handling of mixed (foreground/background) pixels near depth discontinuities. It also provides a novel means for separating foreground and background objects (matting), without the use of a special blue screen. We formulate the problem as the recovery of colors and opacities in a generalized 3D (x, y, d) disparity space, and solve the problem using a combination of initial evidence aggregation followed by iterative energy minimization. 相似文献
122.
The results of the investigations of conversions occurring during synthesis of aluminum oxide and zirconium dioxide porous fibres with alloying additions in the temperature range from 20 to 1300°C are presentated. The analysis of the experimental results enabled to reveal features typical for pyrolitic conversion and sintering of aluminum oxide — and zirconium dioxide — base ceramic fibres. 相似文献
123.
Alexander Kononov Jen-Shin Hong Polina Kononova Feng-Cheng Lin 《Journal of Scheduling》2012,15(4):487-497
Conventional studies on buffer-constrained flowshop scheduling problems have considered applications with a limitation on the number of jobs that are allowed in the intermediate storage buffer before flowing to the next machine. The study in Lin et al. (Comput. Oper. Res. 36(4):1158?C1175, 2008a) considered a two-machine flowshop problem with ??processing time-dependent?? buffer constraints for multimedia applications. A???passive?? prefetch model (the PP-problem), in which the download process is suspended unless the buffer is sufficient for keeping an incoming media object, was applied in Lin et al. (Comput. Oper. Res. 36(4):1158?C1175, 2008a). This study further considers an ??active?? prefetch model (the AP-problem) that exploits the unoccupied buffer space by advancing the download of the incoming object by a computed maximal duration that possibly does not cause a buffer overflow. We obtain new complexity results for both problems. This study also proposes a new lower bound which improves the branch and bound algorithm presented in Lin et al. (Comput. Oper. Res. 36(4):1158?C1175, 2008a). For the PP-problem, compared to the lower bounds developed in Lin et al. (Comput. Oper. Res. 36(4):1158?C1175, 2008a), on average, the results of the simulation experiments show that the proposed new lower bound cuts about 38% of the nodes and 32% of the execution time for searching the optimal solutions. 相似文献
124.
Poly(dimethylsiloxane) (PDMS) polymers end-capped on both ends with pyrene chromophores have been synthesized. Rate constants for end-to-end cyclization 〈 k1 〉 have been determined for dilute solutions of these polymers in toluene solution using a combination of fluorescence decay and steady-state fluorescence measurements. While precise values of the critical exponent for the chain length (N¯) dependence of 〈 k1 〉 are not yet available, these results are consistent with the N¯? 3/2 dependence predicted by Wilemski-Fixman theory. PDMS chains cyclize somewhat more than two times faster than polystyrene chains of the same length in solvents of similar solvating power and viscosity. These results provide strong support for similar predictions made several years ago by Perico and Cuniberti, who used intrinsic viscosity data to parametrize the Rouse-Zimm model for analysis of polymer cyclization dynamics. 相似文献
125.
Anton A. Koval’chuk Alla N. Klyamkina Alexander M. Aladyshev Polina M. Nedorezova Eugeniy M. Antipov 《Polymer Bulletin》2006,56(2-3):145-153
Summary Propylene copolymerization with 1-hexene and 4-methyl-1-pentene in liquid propylene medium in presence of MAO-activated C2-symmetry ansa-zirconocene rac-Me2Si(4-Ph-2-MeInd)2ZrCl2 was studied. Random copolymers of propylene with 1-hexene and 4-methyl-1-pentene content up to 7 mol % were obtained at 60 °C.
General kinetic characteristics of propylene/higher α-olefin copolymerization were evaluated. The distinct feature of propylene
copolymerization with 1-hexene and 4-methyl-1-pentene in liquid propylene medium – the proximity of comonomer relative reactivity
ratios (r1∼r2∼1) that indicates azeotropic nature of copolymerization processes in studied conditions. Synthesized copolymers were characterized
with the use of IR, 13C NMR, GPC, WAXD, DSC techniques, and uniaxial tensile testing. 相似文献
126.
In recent years, polysaccharide-based films have been developed for many applications. Some of these are in the pharmaceutical
industry, where the adhesion of microorganisms to surfaces is a concern. After adhesion of a microorganism to a solid surface
has taken place, the subsequent biofilm formed can act as a vehicle for spreading infections. The aim of this study is to
compare the bacterial adhesion of E. coli and S. aureus from a contaminated solid model (Tryptone Soya Agar) to a range of polysaccharide-based films. These polysaccharide-based
films consist of different natural starches (potato, cassava, wheat, pea and rice) and synthetic polymers hydroxyl-propyl
cellulose (HPC) and carboxyl methyl cellulose (CMC)). The surface energy parameters of the films were calculated from the
contact angle measurements by the sessile drop method. Apolar and polar liquids (water, formamide and hexadecane) and the
Lifshitz-Van der Waals/acid-base (LW/AB) approach were used according to the method of Van Oss, Chaundhury and Good. The surface
properties of the films were also correlated to the microbial adhesion. This indicated that, for both E. coli and S. aureus, the surface roughness did not affect the microbial adhesion. Only had any correlation with the microbial adhesion and was almost constant for all the various polysaccharide films tested. In addition, the electron—donor properties of the materials,
exhibited via , were positively correlated with the adhesion of S. aureus but not with E. coli. This was in agreement with the results of the MATS (Microbial Adhesion To Solvents) test performed on the two bacteria.
This revealed that only S. aureus presented an electron—acceptor characteristic. 相似文献
127.
Polina Ermolaeva 《影响评估与项目评价》2013,31(1):66-71
Based on the environmental case of the 2013 Universiade in Kazan, this research highlights that despite the variety of tools employed for citizen engagement, the key procedures can be claimed as ‘false dialogues’. The study identifies the key factors for such a discrepancy. The main external barriers for post-socialist Russian cities include the limited time frame for building sports venues, poor execution of environmental legislation, and complicated bureaucratic procedures maintained by governmental actors. The internal factors are polarized positions in the community due to the complexity of the project, the gap between the citizen environmental concern and actual engagement in environmentally friendly behaviours associated with the lack of the environmental knowledge, time, and financial resources, lack of knowledge of the environmental impact assessment process, and dominance of the material and paternalistic values and low trust in government proponents. 相似文献
128.
Delaney MF Blodget C Hoey CE McSweeney NE Epelman PA Rhode SF 《Environmental science & technology》2007,41(24):8383-8387
Carefully controlled bench-scale and on-site experiments demonstrated that cyanide can form in the treated drinking water sample container during preservation and storage. In the bench-scale experiment, treated tap water samples were collected on 20 days over six months. The tap water samples were split and some of the splits were spiked with formaldehyde, a known ozone disinfection byproduct, held for three hours and tested for cyanide. Then they were preserved and held for 2-10 days. None of the 69 initial samples had cyanide detects, but 22 of 49 formaldehyde-spiked samples and three of the 20 unspiked samples developed detectable cyanide concentrations during storage. In the on-site experiment, six samples were collected at a finished water tap at an ozone/chloramination treatment plant over three days. Each sample was split, and a portion was spiked with formaldehyde. Each portion was analyzed in triplicate after three different procedures: (1) immediately distilled on-site, (2) stabilized on-site in a distillation tube and distilled back at the laboratory several days later, or (3) following the conventional procedure of preserving the sample to pH > 12 in a container and distilling the sample back at the laboratory. Only the samples handled in the conventional way had detectable amounts of cyanide. Both experiments demonstrated that cyanide can form during conventional preservation and storage, and it is likely that the cyanide detected for this treated drinking water was formed in the sample container as a consequence of the preservation and storage conditions. 相似文献
129.
Gruber June; Eidelman Polina; Johnson Sheri L.; Smith Bailey; Harvey Allison G. 《Canadian Metallurgical Quarterly》2011,120(4):956
Rumination has been consistently implicated in the onset and maintenance of depression. Less work has examined rumination in the context of bipolar disorder, especially rumination about positive emotion. The present study examined rumination about negative and positive emotion in interepisode bipolar disorder (BD; n = 39) and healthy controls (CTL; n = 34). Trait rumination about positive and negative emotion, as well as experiential and physiological responses to a rumination induction, was measured. Illness course was also assessed for the BD group. Results indicated that the BD group reported greater trait rumination about positive and negative emotion compared with the CTL group, though no group differences emerged during the rumination induction. For the BD group, trait rumination about positive and negative emotion, as well as increased cardiovascular arousal (i.e., heart rate), was associated with greater lifetime depression frequency; trait rumination about positive emotion was associated with greater lifetime mania frequency. These findings suggest that interepisode BD is associated with greater rumination about positive and negative emotion, which in turn is associated with illness course. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
130.
Semiconducting polymer-based nanoparticles (Pdots) have recently emerged as a new class of ultrabright probes for biological detection and imaging. This paper describes the development of poly(2,5-di(3',7'-dimethyloctyl)phenylene-1,4-ethynylene) (PPE) Pdots as a platform for designing Fo?rster resonance energy transfer (FRET)-based ratiometric pH nanoprobes. We describe and compare three routes for coupling the pH-sensitive dye, fluorescein, to PPE Pdots, which is a pH-insensitive semiconducting polymer. This approach offers a rapid and robust sensor for pH determination using the ratiometric methodology where excitation at a single wavelength results in two emission peaks, one that is pH sensitive and the other one that is pH insensitive for use as an internal reference. The linear range for pH sensing of the fluorescein-coupled Pdots is between pH 5.0 and 8.0, which is suitable for most cellular studies. The pH-sensitive Pdots show excellent reversibility and stability in pH measurements. In this paper, we use them to measure the intracellular pH in HeLa cells following their uptake by endocytosis, thus demonstrating their utility for use in cellular and imaging experiments. 相似文献