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961.
Leonardo A. de Andrade Matheus R. U. Zingarelli Rodolfo R. Silva Rudinei Goularte 《Multimedia Tools and Applications》2014,71(3):1673-1697
This paper presents a new spatial compression method specifically designed for stereo videos. Different form current compressors, which simply apply known 2D compression techniques, the method proposed here was developed taking into account specificities of the components of the spatial compression process which may impact the correct depth visualization, named Chrominance Subsampling, Discrete WaveletTransform (DWT) and Quantization. Each component was evaluated analyzing where datalosses occur and proposing ways to provide a good balance between compression ratio and image quality, minimizing losses in depth perception. The evaluations were made using standard objective (PSNR) and subjective (DSCQS) metrics, applied to an anaglyphic stereoscopic video base. The results showedour method is competitive regarding compression rate and providessuperior image quality. 相似文献
962.
B. T. Ermagambet B. K. Kasenov N. U. Nurgaliyev M. A. Nabiev Zh. M. Kasenova M. K. Kazankapova A. M. Zikirina 《Solid Fuel Chemistry》2018,52(2):138-141
In this work, the chemical analysis of the initial and activated shale from the Kendyrlyk deposit of Kazakhstan is described. The activated shale was obtained in the high-temperature processes of carbonization and activation in the atmospheres of argon and water vapor, respectively. The electrophysical characteristics of the test shale were determined for first time by measuring the electrocapacity of samples in a temperature range of 293–483 K. The temperature dependences of the specific heat of shale were obtained by dynamic calorimetry. Based on the experimental data, equations for the temperature dependence of the heat capacity of shale were derived; these equations can be subsequently used for determining the thermal conductivity and thermal diffusivity of shale. 相似文献
963.
B. T. Ermagambet B. K. Kasenov N. U. Nurgaliyev M. K. Kazankapova Zh. M. Kasenova A. M. Zikirina 《Solid Fuel Chemistry》2018,52(5):302-307
The thermal activation of Kendyrlyk shale (at temperatures of 700–800°C) facilitates the production of a porous carbon material—activated shale. Currently available techniques such as electron microscopy and IR-spectroscopic analysis were used, and the elemental composition was determined. The morphology of the samples was studied, and the type of carbon modification was revealed; the adsorption characteristics of the samples were determined by the BET method. It was established that the specific surface area and the specific pore volume substantially increased as a result of the high-temperature activation of shale. The resulting activated shale was tested as an adsorbent. 相似文献
964.
New biodegradable poly(ester urethane)/soy protein isolate (PEU/SPI) hybrids were prepared by in situ polymerization. The chemical incorporation of the SPI into the backbone chain of the PEU was facilitated by the reaction of the amine functional groups of SPI with methylene diphenyl diisocyanate (MDI). X-ray diffraction results showed that the chemical incorporation of SPI into PEU significantly changed the molecular structure of the PEU. The PEU/SPI hybrids exhibited higher thermal decomposition temperature and significant increase in the modulus compared with that of pure PEU. Microscopic examination of the morphology of PEU/SPI hybrids confirmed very fine and homogeneous SPI dispersion in PEU. The hydrolytic degradation of the PEU in a phosphate buffer solution was accelerated by incorporation of SPI, which was confirmed by water absorption and scanning electron microscopy of the samples after up to 10 weeks immersion in the buffer solution. This study provides a facile and innovative method of controlling the biodegradation rate of pure PEU with the additional advantage of environmentally-benign biodegradation of the hybrid PEU/SPI polymer, making the concept potentially widely applicable. 相似文献
965.
Using the modified non-linearity approach and the recently introduced Fourier superseries, expressions are derived for the harmonic gains of non-linearities with harmonically related inputs. It is also shown that the extension of the problem to the situation where the commensurate sinusoids are contaminated by noise is straightforward. Examples are given to illustrate the computational procedure. 相似文献
966.
P.P. Hankare M.R. Kadam P.D. Kamble S.D. Jadhav U.B. Sankpal R.P. Patil V.B. Helavi N.S. Gajbhiye 《Journal of Alloys and Compounds》2010,489(1):233-236
The system manganese substituted lanthanum ferrite viz. LaMnxFe1?xO3 (1.0 ≤ x ≥ 0) was prepared by sol–gel autocombusion method. The structural characterization of the samples was carried out by X-ray diffraction technique and it is found that, the phase transfer from cubic to orthorhombic perovskite structure. The lattice parameter and crystallite size decrease with increasing Mn content. The phase formation of perovskite was revealed by thermal analysis technique. The surface morphology and elemental analysis of all the samples were carried out by scanning electron microscopy and energy dispersive X-ray spectroscopic technique, respectively. Electrical properties of the compounds show that, they exhibit semiconducting behavior. The substitution of manganese ions plays an important role in changing their structural, electrical and magnetic properties of lanthanum ferrite. 相似文献
967.
968.
U. L. Basiniuk M. A. Levantsevich N. N. Maksimchenko A. I. Mardasevich 《Journal of Friction and Wear》2013,34(6):438-443
The results of a study on the technological capabilities of the modification of working profile of the teeth of the gears by nanostructured functionally oriented coating particles formed by the method of cladding by a flexible tool (CFT) and evaluated their impact on the reduction of generated tooth gearing noise. It is established that the efficiency of the technology CFT used for the noise reduction of bevel gear drives of machine tools is largely determined by the rational choice of the donor material composition for the formation of a coating. In some cases, gear teeth made from various materials formed on the working profile can significantly change the general character of the distribution of the frequencies of sound energy reducing the level of noise at one frequency and remaining unchanged or even higher at others. The best results in lower noise level of gearing in the whole spectrum of frequencies provided by the bronze-graphite Br05S20Gr0.5DMO0.5 coating. The decrease in noise at the general level was 2–4 dBA depending on rotation speed and, on a separate spectral component, reaches 6–9 dBA. 相似文献
969.
970.
J. P. Tamang S. Dewan S. Thapa N. A. Olasupo U. Schillinger A. Wijaya 《Food Biotechnology》2013,27(1-2):99-112
Abstract This paper is the first report on the microbial population and predominant lactic acid bacteria (LAB) of two soft‐varieties (mild and strong flavoured) of chhurpi., a traditional cheese product of the Sikkim Himalayas. The enzymatic profiles and percentage hydrophobicity (as one criterion of potential adhesion capability) of the predominant LAB were also studied. The LAB, yeasts and viable mesophilic microbial numbers ranged from 7.6–7.9, 7.0–7.4 and 7.7–8.0 log10 cfu/g respectively. The predominant LAB were identified as Lactobacillus plantarum, Lb. curvatus, Lb. fermentum, Lb. paracasei subsp. pseudoplcmtarum and Leuconostoc mesenteroides. They produced a wide spectrum of enzymes and also exhibited similar patterns of enzymatic activity between species. In comparison to the peptidases, they showed relatively weak esterase and lipase activities. No proteinase activity was detected. Most strains had a high degree of hydrophobicity. The results are discussed in relation to the possible role of the strains in food processing. 相似文献