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11.
A new family of biorthogonal wavelets used to identify fault in gears is dealt with. The fault detection analyses and methods presented in this paper are based on signals created by a faultless gear and by a gear with a crack in the tooth root, caused through operating conditions. The new wavelets are a generalization of biorthogonal wavelet systems. In the analysis, smoothness is controlled independently and discrete finite variation is used to optimise the synthesis bank. The procedure measure dispenses with a measure of differentiability, requiring a large number of vanishing wavelet moments in favour of a smoothness measure that is based on the fact that, in most practical applications, only a finite depth of the filter bank tree is involved. 相似文献
12.
Chemical Synthesis,Sintering and Piezoelectric Properties of Ba0.85Ca0.15 Zr0.1Ti0.9O3 Lead‐Free Ceramics 下载免费PDF全文
Klara Castkova Karel Maca Jaroslav Cihlar Hana Hughes Ales Matousek Pavel Tofel Yang Bai Tim W. Button 《Journal of the American Ceramic Society》2015,98(8):2373-2380
The preparation of Ba0.85Ca0.15 Zr0.1Ti0.9O3 (BCZT) powders by wet chemical methods has been investigated, and the powders used to explore relationships between the microstructure and piezoelectric properties (d33 coefficient) of sintered BCZT ceramics. Sol–gel synthesis has been shown to be a successful method for the preparation of BCZT nanopowders with a pure tetragonal perovskite phase structure, specific surface area up to 21.8 m2/g and a mean particle size of 48 nm. These powders were suitable for the fabrication of dense BCZT ceramics with fine‐grain microstructures. The ceramics with the highest density of 95% theoretical density (TD) and grain size of 1.3 μm were prepared by uniaxial pressing followed by a two‐step sintering approach which contributed to the refinement of the BCTZ microstructure. A decrease in the grain size to 0.8–0.9 μm was achieved when samples were prepared using cold isostatic pressing. Using various sintering schedules, BCZT ceramics with broad range of grain sizes (0.8–60.5 μm) were prepared. The highest d33 = 410.8 ± 13.2 pC/N was exhibited by ceramics prepared from sol–gel powder sintered at 1425°C, with the relative density of 89.6%TD and grain size of 36 μm. 相似文献
13.
Jernej Zupanc Damjana Drobne Barbara Drasler Janez Valant Ales Iglic Veronika Kralj-Iglic Darko Makovec Michael Rappolt Barbara Sartori Ksenija Kogej 《Carbon》2012,50(3):1170-1178
There are some molecular dynamic simulations but a paucity of experimental evidence of the effects of C-60 fullerene on lipid bilayers. The aim of this study is to assess the potential for disruption of the lipid bilayer by C-60 suspended in water. We selected a C-60 suspension that has previously been shown to provoke cell membrane destabilisation in vivo. Electromobility measurements show significant negative surface charge on the C-60 nanoparticles suspended in a glucose solution and a zeta potential of ?26 mV. The prevalent C-60 clusters have hydrodynamic radii of approximately 2 nm. Phase contrast microscopy and computer aided image analysis results show that C-60 causes shape transformations and rupture of unilamellar phospholipid vesicles, indicative of changes in their average mean curvature. Small-angle X-ray scattering reveals that C-60 provokes disruptions of external membranes of multilamellar vesicles only after freeze and thaw cycles. Here, the liposomes undergo breakage and annealing steps which increase the probability for fullerenes to insert into the MLVs. Our experimental findings confirm the potential of C-60 to reconstruct lipids in biological membranes. This research enhances our understanding of the impact of engineered nanoparticles on cell membranes. 相似文献
14.
Ales Landfeld Pavla Novotna Jan Strohalm Milan Houska Karel Kyhos 《International Journal of Food Properties》2013,16(1):165-169
The viscosity of cocoa butter was measured in the range of temperatures 30‐70°C. Product in thawed state behaved as the Newtonian fluid with viscosity independent of shear rate. This behaviour was changed when the temperature reached 30°C. From this temperature the product behaved as non‐Newtonian fluid which was caused by the presence of the first fat crystals. The solidification was detected between 27‐30°C. A comparison of the measured data of viscosity with literature data has been done. The good agreement of literature data enabled us to select the general equation for prediction of cocoa butter viscosity in the thawed state as a function of temperature for the range 30‐97°C. 相似文献
15.
Jana Orsavova Ladislava Misurcova Jarmila Vavra Ambrozova Robert Vicha Jiri Mlcek 《International journal of molecular sciences》2015,16(6):12871-12890
Characterizations of fatty acids composition in % of total methylester of fatty acids (FAMEs) of fourteen vegetable oils—safflower, grape, silybum marianum, hemp, sunflower, wheat germ, pumpkin seed, sesame, rice bran, almond, rapeseed, peanut, olive, and coconut oil—were obtained by using gas chromatography (GC). Saturated (SFA), monounsaturated (MUFA) and polyunsaturated fatty acids (PUFA), palmitic acid (C16:0; 4.6%–20.0%), oleic acid (C18:1; 6.2%–71.1%) and linoleic acid (C18:2; 1.6%–79%), respectively, were found predominant. The nutritional aspect of analyzed oils was evaluated by determination of the energy contribution of SFAs (19.4%–695.7% ERDI), PUFAs (10.6%–786.8% ERDI), n-3 FAs (4.4%–117.1% ERDI) and n-6 FAs (1.8%–959.2% ERDI), expressed in % ERDI of 1 g oil to energy recommended dietary intakes (ERDI) for total fat (ERDI—37.7 kJ/g). The significant relationship between the reported data of total fat, SFAs, MUFAs and PUFAs intakes (% ERDI) for adults and mortality caused by coronary heart diseases (CHD) and cardiovascular diseases (CVD) in twelve countries has not been confirmed by Spearman’s correlations. 相似文献
16.
Vilem Pechanec Ales Vavra Martina Hovorkova Jan Brus Helena Kilianova 《International journal of remote sensing》2013,34(3):967-987
The paper describes the analyses of moisture parameters and biomass of vegetation cover. These include a relative moisture classification, a relative biomass classification, and the actual aboveground biomass estimate. All analyses were carried out by applying spectral indices and fuzzy classification for assessment. The satellite imagery from the Thematic Mapper (TM) (Landsat 5) and the Enhanced Thematic Mapper Plus (ETM+) (Landsat 7) was used as input data. Biomass indices derived from the satellite imagery were correlated with table data of average crop yields in 2007. Since the imagery used was from three periods of time (May 2001, July 2007, August 2000), it could have been assessed in terms of both time dependence and phenological phases. The monitored variables during the year were the relative moisture and vegetation biomass. The territory of interest was the Trkmanka River basin in southeast Moravia. Time dependence was obtained with the results of classifications in terms of varying phenological phases as well as dependence between the two characteristics. The data from the comparison of May and June revealed primarily their increase (a decrease occurred only on arable land), whereas those from the comparison of July and August revealed mainly their decrease. The two characteristics show almost linear mutual dependence except for some forest land. We processed map outputs showing the spectral indices used, changes in relative moisture and relative biomass, the actual biomass estimate, and a deviation from a linear dependence of the two characteristics under examination. The selected indices were processed into Geoscientific Model Development (GMD) – models that can be repeatedly run in Model Maker in Earth Resources Data Analysis System (ERDAS) IMAGINE. Together with the models of spectral indices, these were optimized for the sensor TM and ETM+. 相似文献
17.
In this article, we propose a meta-model for formal specification of functional requirements for configurable content- and context-aware dynamic service selection in business process models with the objective to enable greater flexibility of the modeled processes. The dynamic service selection can cope with highly dynamic business environments that today's business processes must handle. Modeling functional requirements for dynamic service selection in business process models is not well covered in literature. Some partial solutions exist but none of them allows modeling a complete set of functional requirements for the selection similar to the one we are addressing in this article. Our meta-model enables formal specification of service selection relevant data extracted from service request message, custom configuration data (e.g., thresholds), process and task definition/instance metadata, and service selection rules. The meta-model is configurable and content- and context-aware. Processes leveraging our meta-model can adapt to changing requirements without redesign of the process flow. Proposed meta-model allows users to additionally configure the models at run time (e.g., raising a threshold). Modeling can be divided into roles with different required competences. We implement our meta-model in BPMN 2.0 (Business Process Model and Notation) through specific extensions to the BPMN semantic and diagram elements. By measuring complexity of real-world sample process models we show that using our solution modelers can efficiently model business processes that need to address frequent changing demands. Compared to available alternatives, models using our solution have on average ~13% fewer activities, ~16% fewer control-flow elements and ~22% fewer control paths. By reading ~10% smaller models (by volume) model readers get more flexible process models that capture all functional requirements for the dynamic selection. 相似文献
18.
Ratikanta Mishra Ales Kroupa Adela Zemanova Herbert Ipser 《Journal of Electronic Materials》2013,42(4):646-653
Phase equilibria in the ternary Ni-Sb-Sn system are of interest for high-temperature soldering, both considering ternary alloys as solder materials themselves or as the basis for understanding the reactions between Sb-Sn-based solders and Ni-based substrates. Therefore, the Sn-rich corner of the ternary Ni-Sb-Sn phase diagram with Sn content of more than 75 at.% was investigated by a combination of powder x-ray diffraction (XRD), differential thermal analysis (DTA), and electron probe microanalysis (EPMA). Ternary phase equilibria and phase compositions of the respective equilibrium phases were determined within the isothermal section at 200°C, and two isopleths were constructed for constant Sn contents of 80 at.% and 85 at.%. The experiments were supported by CALPHAD-type calculations of this ternary system to yield a consistent reaction scheme which shows four invariant ternary transition reactions in this composition range. A liquidus projection is presented, accompanied by the corresponding Scheil diagram. 相似文献
19.
Styskalik Ales Kordoghli Imene Poleunis Claude Delcorte Arnaud Dochain Denis D. Moravec Zdenek Vida Julius Homola Tomas Aprile Carmela Fusaro Luca Devred François Debecker Damien P. 《Journal of Materials Science》2021,56(25):14001-14018
Journal of Materials Science - Hybrid materials are intensely studied for potential applications in heterogeneous catalysis. Organic groups at the catalyst surface can modify not only its... 相似文献
20.
Opatrný K Krouzzecký A Polanská K Mares J Tomsů M Bowry SK Vienken J 《Hemodialysis international. International Symposium on Home Hemodialysis》2006,10(2):201-208
The aim of the study was to assess the biocompatibility profile of a newly developed high-flux polysulfone dialyzer type (FX-class dialyzer). The new class of dialyzers incorporates a number of novel design features (including a new membrane) that have been developed specifically in order to enhance the removal of small- and middle-size molecules. The new FX dialyzer series was compared with the classical routinely used high-flux polysulfone F series of dialyzers. In an open prospective, randomized, crossover clinical study, concentrations of the C5a complement component, and leukocyte count in blood and various thrombogenicity parameters were evaluated before, and at 15 and 60 min of hemodialysis at both dialyzer inlet and outlet in 9 long-term hemodialysis patients using the FX60S dialyzers and, after crossover, the classical F60S, while in another 9 patients, the evaluation was made with the dialyzers used in reverse order. The comparison of dialyzers based on evaluation of the group including all procedures with the FX60S and the group including procedures with the F60S did not reveal significant differences in platelet count, activated partial thromboplastin times, plasma heparin levels, platelet factor-4, D-dimer, C5a, and leukocyte count at any point of the collecting period. Both dialyzer types showed a significant increase in the plasma levels of the thrombin-antithrombin III complexes; however, the measured levels were only slightly elevated compared with the upper end of the normal range. Biocompatibility parameters reflecting the behavior of platelets, fibrinolysis, complement activation, and leukopenia do not differ during dialysis with either the FX60S or the F60S despite their large differences in design and geometry features. Although coagulation activation, as evaluated by one of the parameters used, was slightly higher with the FX60S, it was still within the range seen with other highly biocompatible dialyzers and therefore is not indicative of any appreciable activation of the coagulation system. Thus, the incorporation of various performance-enhancing design features into the new FX class of dialyzers does not result in a deterioration of their biocompatibility profile, which is comparable to that of the classical F series of dialyzers. 相似文献