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991.
Aykut Avci Jan De CockPeter Lambert Roel BeernaertJelle De Smet Lawrence BogaertYouri Meuret Hugo ThienpontHerbert De Smet 《Journal of Visual Communication and Image Representation》2012,23(2):287-292
An efficient disparity estimation algorithm for multi-view video sequences, recorded by a two-dimensional camera array in which the cameras are spaced equidistantly, is presented. Because of the strong geometrical relationship among views, the disparity vectors of a certain view can for most blocks be derived from the disparity vectors of other views. A frame constructed using that idea is called a D frame in this work. Three new prediction schemes which contain D frames are proposed for encoding 5 × 3 multi-view video sequences. The schemes are applied to several multi-view image sequences taken from a camera-array and they are compared in terms of quality, bit-rate and complexity. The experimental results show that the proposed prediction schemes significantly decrease the complexity of the encoder at a very low cost of quality and/or bit-rate. 相似文献
992.
A novel method for the extraction of (−)epigallocatechin gallate of high purity from green tea leaves is proposed in this
study. The method comprised a two-stage water-based extraction followed by successive use of microfiltration and ultrafiltration.
Microfiltration was used as a pretreatment to ultrafiltration. The best process conditions of each unit operation were estimated
by performing well-planned experimentations. The clarified liquor was dried to powder by freeze drying. Chemical analyses
revealed that the tea powder contained about 90% of polyphenols. The purity of (−)epigallocatechin gallate was found to be
about 80%, while its average yield was 1.22 g/l. The method outlined in this study may have remarkable importance for the
bulk production of high-purity (−)epigallocatechin gallate with potential application in pharmaceutical, cosmetic, and food-processing
industries. Besides being a green process, this method can be easily scaled up for the commercial production of (−)epigallocatechin
gallate. 相似文献
993.
A qualitative and quantitative research has been performed on the physico-chemical parameters of the neighboring coastal waters of the rivers Matla and Saptamukhi in the Sunderban district, West Bengal. The distribution pattern of eight physico-chemical parameters, namely pH, salinity, dissolved oxygen, suspended solids, nitrogen and phosphorus concentrations (inorganic and total) has been graphed and compared for the two rivers over a time period of ten years (??90s decade). A statistical analysis has been carried out and the correlation data between these parameters has been rationalized based on both natural and man-made activities during that time. This has pointed to various causes behind coastal pollution of river waters. The changes in water quality have been related to flood impacts, storm surge, eutrophication, domestic sewage, agricultural and industrial wastes. In order to avoid coastal degradation and maintain environmental balance, it is very important to understand the impact of these parameters on coastal zones. 相似文献
994.
Jin-Kyung Kim Yuri Estrin Bruno C. De Cooman 《Metallurgical and Materials Transactions A》2018,49(12):5919-5924
The present article proposes a constitutive model that includes the stacking fault energy (SFE)-dependence of the deformation behavior of Fe-Mn-C-(Al) TWIP steels. The different kinetics of the SFE-dependent strain hardening of twinned and twin-free grains are accounted for. The high flow stress of TWIP steels investigated is attributed to the combined effect of a large fraction of twinned grains and a low dynamic recovery rate—both effects being associated with its lowest SFE. 相似文献
995.
Hans Steenackers Kim Hermans Jos Vanderleyden Sigrid C.J. De Keersmaecker 《Food research international (Ottawa, Ont.)》2012,45(2):502-531
The ability of Salmonella to form complex surface-associated communities, called biofilms, contributes to its resistance and persistence in both host and non-host environments and is especially important in food processing environments. In this review, the different types of abiotic (plastic, glass, cement, rubber, and stainless steel) and biotic surfaces (plant surfaces, epithelial cells, and gallstones) on which Salmonella biofilms have been described are discussed, as well as a number of commonly used laboratory setups to study Salmonella biofilm formation (rdar morphotype, pellicle formation, and biofilms on polystyrene pegs). Furthermore, the structural components important during Salmonella biofilm formation are described (curli and other fimbriae, BapA, flagella, cellulose, colanic acid, anionic O-antigen capsule and fatty acids), with special attention to the structural variations of biofilms grown on different surfaces and under different conditions. Indeed, biofilm formation is strongly influenced by different environmental signals, via a complex regulatory network. An extensive overview is given on the current understanding of this genetic network and the interactions between its different components (CsgD, RpoS, Crl, OmpR, IHF, H-NS, CpxR, MlrA, c-di-GMP, BarA/SirA, Csr, PhoPQ, RstA, Rcs, metabolic processes and quorum sensing). To further illustrate that biofilm formation is a mechanism of Salmonella to adapt to different environments, the resistance of Salmonella biofilms against different stress factors including desiccation stress, disinfectants (e.g. hypochlorite, glutaraldehyde, cationic tensides and triclosan) and antibiotics (e.g. ciprofloxacin) is described. Finally, a number of Salmonella biofilm inhibitors, identified through bottom-up- and top-down-approaches, are discussed, such as surfactin, glucose, halogenated furanones, 4(5)-aryl 2-aminoimidazoles, furocoumarins and salicylates. Also the potential of combination therapy (e.g. combinations of triclosan and quaternary ammonium salts or halogenated furanones and antibiotics/disinfectants) and nano- and micro-emulsions to inhibit Salmonella biofilm formation is discussed. Insight into the pathogen's complex biofilm process will eventually lead to further unraveling of its intricacies and more efficient strategies to combat Salmonella biofilms. 相似文献
996.
Simona De Marino Carmen Festa Franco Zollo Filomena Incollingo Gennaro Raimo Giovanna Evangelista Maria Iorizzi 《Food chemistry》2012
In the present study, the chemical composition and antioxidant activities of Teucrium polium L. (Lamiaceae) were assessed. Fractionation of methanol extract obtained from the aerial parts of T. polium yielded one new phenylethanoid glycoside, named poliumoside B, together with four known flavonoids, two iridoid glycosides and a known poliumoside. The structures of all of these compounds were elucidated on the basis of spectroscopic data from 1D and 2D NMR experiments and MS spectral analyses. The antioxidant activities of the crude extracts and of the isolated compounds were evaluated through tests such as DPPH radical-scavenging capability, reducing power, xanthine oxidase inhibitory effect and inhibition of linoleic acid peroxidation. The highest antioxidant activity was found in the n-butanol extract, which also contained active polyphenols, thus suggesting that this plant could be used as a source of natural molecules, to provide safe antioxidant additives and nutraceuticals. The structure–activity relationships of the isolated compounds are also discussed. 相似文献
997.
How do the new building façade components work under real climatic conditions? The question is especially related to the dynamic behaviour of new and complex components such as the ventilated walls, the Phase Change Material, or others that use nano-technologies and aerogels. One of the objectives of the undergoing research activity, named Abitare Mediterraneo, is the evaluation of their thermal behaviour through the use of an outdoor test cell, in order to reproduce under the real external conditions the performance of these components, and consequently define the main thermal parameters such as the attenuation factor and the thermal inertia, characterising the component; moreover, the results will be used to write new algorithms for dynamic simulation tools allowing an appropriate evaluation of the complex behaviour of the whole building at a real scale condition. The new test cell is realised in Florence, Italy. The design starts from the study of the experience of the existing PASSYS test cells, overtaking the main weakness of the building structure and of the heat-flux sensors. 相似文献
998.
Gianluigi De Falco Mario Commodo Carmela Bonavolontà Giovanni Piero Pepe Patrizia Minutolo Andrea D’Anna 《Combustion and Flame》2014
Optical and electrical properties of carbonaceous particles produced in laboratory scale, premixed ethylene/air flames are obtained. Light absorption and Raman spectroscopy show that the change in particle nanostructure follows a graphitization trajectory as the flame richness increases. The optical band gap decreases and the size of the aromatic network in the particle increases, while the interlayer spacing between parallel layers decreases. The electrical conductivity of the materials increases by increasing flame richness in agreement to the graphitization trajectory. A non-ohmic behavior has been found and explained in terms of electron tunneling in a percolative network. Our results show that the electrical properties of flame formed carbon nanoparticles are strongly dependent on their nanostructure, and hence they have to be used carefully for the determination of particle concentration with conductometric sensors. Moreover, the dependence of the electrical properties of combustion formed particles might be useful for the development of cheap sensors for the selective detection of different classes of combustion aerosols. 相似文献
999.
Hemodialysis treatment is biased by complications during its operative phases. One of these potential accidents consists in intradialytic hypotension, that causes discomfort to the patient and may even increase the risk of death. Therefore, it is very important to predict these events in routine clinical procedures. A cause of hypotension may be thermal energy/heat exchanges between extracorporeal system and the surrounding environment. A model to evaluate these heat losses is proposed and improved in order to maintain constant patient blood temperature. A convenient procedure is defined to improve and optimize clinical treatment. Although most hemodialysis machines automatically control the dialysate solution temperature starting from peripheral body temperature measurements, the proposed method is based on the control of the pre-dialysis core temperature of the patient, and the temperature of the blood entering the artery from the extracorporeal circuit after the treatment in the dialyzer. Measurements of arterial and venous blood temperatures are obtained in a non invasive way by a suitable estimate of the thermal energy exchanges between the blood and the environment during the extracorporeal recirculation. The suggested model guarantees a constant core temperature of the patient, improving prevention from intradialytic hypotension. 相似文献
1000.