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61.
62.
This paper focuses on the detection of objects with a Lambertian surface under varying illumination and pose. We offer to apply a novel detection method that proceeds by modeling the different illuminations from a small number of images in a training set; this automatically voids the illumination effects, allowing fast illumination invariant detection, without having to create a large training set. It is demonstrated that the method “fits in” nicely with previous work about modeling the set of object appearances under varying illumination. In the experiments, an object was correctly detected under image plane rotations in a 45° range, and a wide variety of different illuminations, even when significant shadows were present. 相似文献
63.
Method for reconstructing atmospheric optical parameters from the data of polarization lidar sensing
Inversion of polarization lidar sensing data based on the form of the lidar sensing equation with allowance for contributions from multiple-scattering calls for a priori information on the scattering phase matrix. In the present study the parameters of the Stokes vectors for various propagation media, including those with the scattering phase matrices that vary along the measuring range, are investigated. It is demonstrated that, in spaceborne lidar sensing, a simple parameterization of the multiple-scattering contribution is applicable and the polarization signal's characteristics depend mainly on the lidar and depolarization ratios, whereas differences in the angular dependences of the matrix components are no longer determining factors. An algorithm for simultaneous reconstruction of the profiles of the backscattering coefficient and depolarization and lidar ratios in an inhomogeneous medium is suggested. Specific features of the methods are analyzed for the examples of interpretation of lidar signal profiles calculated by the Monte Carlo method and are measured experimentally. 相似文献
64.
65.
Christo Kratchanov Stamen Stamov Mariana Popova und Margarita Kuntscheva 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1978,167(5):338-341
Zusammenfassung Es wurde nachgewiesen, daß die untersuchten Äthylester (Äthylpektine) wesentlich bessere Emulgiereigenschaften als das Ausgangs-Sonnenblumenpektin haben. Die Dispersität und die Viscosität der Emulsionen erhöht sich mit der Konzentration der Äthylpektine und der Ölphase. Die Stabilität der Emulsionen wird bei steigender Konzentration von Äthylpektin und Ölphase verbessert. Es wurde festgestellt, daß die Emulgierfähigkeiten von Äthylestern des Sonnenblumenpektins auch vom Veresterungsgrad abhängen. Die besten Ergebnisse erzielt man mit Derivaten, die einen Veresterungsgrad von etwa 65% haben.
Emulsifying properties of ethylesters of sunflower pectin
Summary It has been shown that the studied ethylesters (ethylpectins) have far better emulsifying properties than the initial sunflower pectin.The dispersity, viscosity and stability of the emulsions increase with increasing concentration of the ethylpectins and the oily phase. It has been found that the emulsifying properties of ethylesters of the sunflower pectin depend also on the degree of esterification. Best results are achieved with derivatives which have a degree of esterification of about 65%.相似文献
66.
67.
Use of antimicrobial biodegradable packaging to control Listeria monocytogenes during storage of cooked ham 总被引:5,自引:0,他引:5
Marcos B Aymerich T Monfort JM Garriga M 《International journal of food microbiology》2007,120(1-2):152-158
The antimicrobial effect against L. monocytogenes of biodegradable films (alginate, zein and polyvinyl alcohol) containing enterocins was investigated. Survival of the pathogen was studied by means of challenge tests performed at 6 degrees C during 8 and 29 days, for air-packed and vacuum-packed sliced cooked ham, respectively. Air packaging was tested with two concentrations of enterocins (200 and 2000 AU/cm2). Control air-packed cooked ham showed an increase of L. monocytogenes from 10(4) to 10(7) CFU/g after 8 days. By contrast, packaging with antimicrobial films effectively slowed down the pathogen's growth, leading to final counts lower than in control lots. Air-packaging with alginate films containing 2000 AU/cm2 of enterocins effectively controlled L. monocytogenes for 8 days. An increase of only 1 log unit was observed in zein and polyvinyl alcohol lots at the same enterocin concentration. Vacuum packaging with films containing enterocins (2000 AU/cm2) also delayed the growth of the pathogen. No increase from inoculated levels was observed during 15 days in antimicrobial alginate films. After 29 days of storage, the lowest counts were obtained in samples packed with zein and alginate films containing enterocins, as well as with zein control films. The most effective treatment for controlling L. monocytogenes during 6 degrees C storage was vacuum-packaging of sliced cooked ham with alginate films containing 2000 AU/cm2 of enterocins. From the results obtained it can concluded that antimicrobial packaging can improve the safety of sliced cooked ham by delaying and reducing the growth of L. monocytogenes. 相似文献
68.
Igor Tomasevic Margarita Dodevska Milan Simić Smiljana Raicevic Violeta Matovic Ilija Djekic 《Food Additives and Contaminants: Part B: Surveillance Communications》2018,11(1):49-53
In total 7351 meat preparations and fresh processed meat products were analysed from 555 different Serbian meat producers over a 10-year period, 4.5 years before and 5.5 years after mandatory Hazard Analysis and Critical Control Points (HACCP) implementation. From the obtained results, it could be concluded that HACCP has contributed to a better alignment of practices with the legal provisions. The share of non-compliant samples dropped from 18.6% before HACCP to 8.3% after its mandatory implementation. Average sulphite concentrations for all categories of meat preparations and fresh processed meat products decreased by 43%, declining from 33.6 to 19.3 mg kg?1. Typical misuse and frequent abuse of sulphites was independent of a season. Application of HACCP principles in the Serbian meat industry raised awareness about the misuse of sulphites and contributed to a better control, minimising exposure to sulphites. 相似文献
69.
Characteristics of Convective Drying of Pepino Fruit (Solanum muricatum Ait.): Application of Weibull Distribution 总被引:2,自引:0,他引:2
Elsa Uribe Antonio Vega-G��lvez Karina Di Scala Romina Oyanadel Jorge Saavedra Torrico Margarita Miranda 《Food and Bioprocess Technology》2011,4(8):1349-1356
The aim of this research was to study the behaviour of the drying kinetics of pepino fruit (Solanum muricatum Ait.) at five temperatures (50, 60, 70, 80 and 90 °C). In addition, desorption isotherms were determined at 20, 40 and 60 °C
over a water activity range from 0.10 to 0.90. The Guggenheim, Anderson and de Boer model was suitable to depict the desorption
data. A monolayer moisture content from 0.10 to 0.14 g water g−1 d.m. was reported. The equations of Newton, Henderson–Pabis, Modified Page, Wang–Singh, Modified Henderson–Pabis, Logarithmic
as well as standardised Weibull were tested for modelling drying kinetics. Besides, Fick’s second law model was used to calculate
the water diffusion coefficient which increased with temperature from 2.55 to 7.29 × 10−10 m2 s−1, with estimated activation energy of 27.11 kJ mol−1. The goodness of fit of the models was evaluated using sum squared error and chi-square statistical tests. The comparison
of the experimental moisture values with respect to the calculated values showed that the standardised Weibull model presented
the best goodness of fit, showing that this equation is very accurate for simulating drying kinetics for further optimisation
of drying times. 相似文献
70.
Preservation of different fig cultivars (Ficus carica L.) under modified atmosphere packaging during cold storage 下载免费PDF全文