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141.
Kazimierz Choroś 《Multimedia Tools and Applications》2016,75(24):16923-16942
The paper proposes measures for weighted indexing of sports news videos. The content-based analyses of sports news videos lead to the classification of frames or shots into sports categories. A set of sports categories reported in a given news video can be used as a video representation in visual information retrieval system. However, such an approach does not take into account how many sports events of a given category have been reported and how long these events have been presented in news for televiewers. Weighting of sports categories in a video representation reflecting their importance in a given video or in a whole video data base would be desirable. The effects of applying the proposed measures have been demonstrated in a test video collection. The experiments and evaluations performed on this collection have also shown that we do not need to apply perfect content-based analyses to ensure proper weighted indexing of sports news videos. It is sufficient to recognize the content of only some frames and to determine the number of shots, scenes or pseudo-scenes detected in temporal aggregation process, or even only the number of events of a given sports category in a sports news video being indexed. 相似文献
142.
Jerzy Jedliński Jean-Luc Grosseau-Poussard Kazimierz Kowalski Jarosław Dąbek Günter Borchardt 《Oxidation of Metals》2013,79(1-2):41-51
The development of the oxide scale on model Fe20Cr5Al-type alloys unmodified and containing implanted yttrium was studied in oxygen-dominated atmosphere at 1,100 °C for up to 1 h. A two-stage-oxidation exposure was applied with the use of 18O2 as a tracer. The choice of the exposure durations ensured the possibility to follow the consecutive stages of scale development. The oxidized samples were characterized using SEM (morphology); PLS (phase composition), and SIMS (elemental distributions). The obtained results are discussed in terms of the mechanism of the development of protective α-Al2O3 scale and the effect of the additions on this process taking into account the necessity of distinguishing the mechanism and kinetics of the scale evolution. Similar scale evolution stages were found on both studied materials and in both cases the protective α-Al2O3 scale developed rapidly, already after the exposure for 3 min. Implanted yttrium appeared to have a negligible effect on the evolution of the scale. It only slightly retarded the evolution which can be attributed rather to a kinetic effect than to mechanistic one. However, the mechanical failure of the scales via formation of cracks at the asperities of convolutions occurred on the yttrium-implanted alloy but not on the non-implanted one. 相似文献
143.
In this paper, the possibilities for forming non-circular pulleys using laser cutting techniques and cutting techniques using water jets with abrasive materials are described. Research on laser cutting with use of gases for formation of carbon steel and acid-resistant steel pulleys is also discussed. The advantages of water jet cutting of non-circular pulleys are shown, and the methodology for measuring machined pulleys with a coordinate measuring technique is also presented. Use of computer-aided design systems with a range of software enabling automation of CNC contour saw control and optimization processes for formed elements spacing are all also discussed. 相似文献
144.
Kornelia Wiśniewska Waldemar Pichór Ewelina Kłosek-Wawrzyn 《International Journal of Applied Ceramic Technology》2021,18(3):1063-1073
Sintered ceramics, represented by ceramic tiles or clinker bricks, are widely used in the building materials industry due to their technological properties and visual qualities. The topic of color changing of ceramic materials from cream-firing clays with the use of mineral additives has not been addressed to date. The aim of the paper was to investigate the effect of granulation of dolomite additives to ceramic masses based on cream-firing Borkowice clay on the color and properties of fired ceramic materials. The paper proposes that grain size of mineral additive affects the color of sintered ceramics. In order to confirm this hypothesis, a number of experiments were performed, consisting of determination of the color and technological properties of ceramic materials. The conducted tests showed that the color and technological properties of sintered ceramics are influenced by the grain size of the additives used. 相似文献
145.
Małgorzata Wiśniewska Stanisław Chibowski Teresa Urban 《Journal of Industrial and Engineering Chemistry》2013,19(1):263-271
The effect of solution pH and molecular weight of polyethylene glycol (PEG) and polyethylene oxide (PEO) on their adsorption as well as stability of the colloidal Al2O3 water suspension was studied. The following methods were applied: turbidimetry, spectrophotometry, viscosimetry, potentiometric titration and microelectrophoresis.It was shown that the increasing solution pH affects conformation of the adsorbed macromolecules which affects the stability properties of such systems. The polymer adsorption causes deterioration of the stability conditions of the investigated alumina systems in comparison to those without polymer at all investigated pH values. At pH 3 and 6 the effect of the suspension destabilization is significantly smaller than at pH 9. The most effective flocculent of Al2O3 water suspension is PEO of the molecular weight 218,000 at pH 9. 相似文献
146.
AbstractThis article presents the results of numerical simulation and experimental study of a multi-pin electrohydrodynamic (EHD) dryer. Combined effect of EHD flow and the external air cross-flow on drying performance was investigated with 3-D numerical model, which accounts for electric field, electric charge transport, external air cross-flow and material-gas moisture transport. Effect of cross-flow air stream on drying was positive in the range of low velocities, changing to negative at high velocities due to counteracting with EHD flow. Numerical simulation predicted previously unknown effect of EHD flow on the cross-flow air stream, which was quantified as an increase of airway resistance. This prediction was fully validated by experiments. Both numerical simulation and experiment proved that for given intensity of EHD flow there is an optimum value of the cross-flow, resulting in maximum drying performance. The numerical model can be applied to determine the optimal operating parameters for multi-pin EHD dryer. 相似文献
147.
Goulon J Rogalev A Goujon G Wilhelm F Ben Youssef J Gros C Barbe JM Guilard R 《International journal of molecular sciences》2011,12(12):8797-8835
X-ray Detected Magnetic Resonance (XDMR) is a novel spectroscopy in which X-ray Magnetic Circular Dichroism (XMCD) is used to probe the resonant precession of local magnetization components in a strong microwave pump field. We review the conceptual bases of XDMR and recast them in the general framework of the linear and nonlinear theories of ferromagnetic resonance (FMR). Emphasis is laid on the information content of XDMR spectra which offer a unique opportunity to disentangle the precession dynamics of spin and orbital magnetization components at given absorbing sites. For the sake of illustration, we focus on selected examples in which marked differences were found between FMR and XDMR spectra simultaneously recorded on ferrimagnetically ordered iron garnets. With pumping capabilities extended up to sub-THz frequencies, high-field XDMR should allow us to probe the precession of orbital magnetization components in paramagnetic organometallic complexes with large zero-field splitting. Even more challenging, we suggest that XDMR spectra might be recorded on selected antiferromagnetic crystals for which orbital magnetism is most often ignored in the absence of any supporting experimental evidence. 相似文献
148.
Janusz Nowicki Julia Woch Małgorzata Mościpan Andrzej Robaszkiewicz Rafał Grabowski Izabela Semeniuk Karol Erfurt 《Journal of surfactants and detergents》2017,20(6):1475-1481
The synthesis of selected polyoxyethylene–polyoxypropylene block copolymer (poloxamer) fatty acid monoesters is presented. Organotin homogeneous catalyst Sn bis(2‐ethylhexanoate) effectively catalyzed the esterification reaction of (EO)–(PO)–(EO) block copolymer (poloxamer) with fatty acids. The reaction proceeded in high yield and high selectivity to monoesters. Content of diesters in final products was below 1 wt%. The new protocol opened up a high yield and high selective method for the synthesis of poloxamer fatty acid monoesters. These products are potentially interesting for industrial applications, e.g. in lubricants, cosmetics and, in particular, as potential emulsifying agents compatible with hydrocarbon bases, such as paraffin. 相似文献
149.
Wojciech Łukasz Grześkowiak 《火与材料》2012,36(1):75-83
This article presents the results of investigations obtained for a wood fire retardant agent which is currently under production. Experiments were conducted using a mixture of potassium carbonate and urea in accordance with the PN‐C‐04914 standard (the Polish equivalent of ISO 5660‐1). Wood samples of Scots pine (Pinus sylvestris L.) were treated with the above mixture as well as with its individual components. It was observed that impregnation of samples with potassium carbonate and a mixture of potassium carbonate and urea has an advantageous influence on the reduction of the heat release and the heat of combustion, and also prolongs the time to ignition. Urea alone failed to exert a fire‐retardant effect on wood samples. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
150.
M Szczecińska M Kwaśniewski J Sawicki K Chwiałkowska K Szandar W Pisarek 《International journal of molecular sciences》2012,13(8):9893-9899
We identify a large number of microsatellites from Galium trfidum, a plant species considered rare and endangered in Central and Western Europe. Using a combination of a total enriched genomic library and small-scale 454 pyrosequencing, we determined 9755 contigs with a length of 100 to 6192 bp. Within this dataset, we identified 153 SSR motifs in 144 contigs. Here, we tested 14 microsatellite loci in 2 populations of G. trifidum. The number of alleles and expected heterozygosity were 1-8 (mean 3.2) and 0.00-0.876 (0.549 on average), respectively. The markers described in this study will be useful for evaluating genetic diversity within and between populations, and gene flow between G. trifidum populations. These markers could also be applied to investigate the biological aspects of G. trifidum, such as the population dynamics and clonal structure, and to develop effective conservation programs for the Central European populations of this species. 相似文献