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21.
SEBASTIANO PORRETTA † GIUSEPPE CARPI GIANFRANCO DALL'AGLIO CLAUDIO GHIZZONI 《International Journal of Food Science & Technology》1992,27(4):427-433
The characteristics of high-quality tomato pulp (commercial def.: crushed or diced tomatoes with about 30% tomato juice as packing medium) canned with tomato juice pulp enriched by ultrafiltration as packing medium were compared with those covered with conventional vacuum-concentrated juice.
Both hot- and cold-break products were prepared and those containing 20% serum-reduced packing juice proved to be the best, showing no signs of syneresis on storage and with improvements in sensory properties, colour and non-enzymatic browning; some volatile components were reduced. 相似文献
Both hot- and cold-break products were prepared and those containing 20% serum-reduced packing juice proved to be the best, showing no signs of syneresis on storage and with improvements in sensory properties, colour and non-enzymatic browning; some volatile components were reduced. 相似文献
22.
V Arvis B Michalet‐Doreau C Debain 《Journal of the science of food and agriculture》2004,84(14):1848-1854
We present a new computer vision method for measuring the physical characteristics of maize silages based on the extraction of image textural features, namely five Haralick features, the moments of order 1 and 2 on the grey levels of the image, and a fractal parameter. To show the effectiveness of these features for characterising the physical properties of the maize silage, a trial was performed on three maize cultivars (Zea mays L, a mid–early hybrid and an early hybrid) to study the effects of the ensiling process. The features could discern effects of the ensiling process on the physical properties of the maize silage. These effects were neither significant by comparing particle size distributions, nor with chemical compositions, whereas a biological response (degradation in the rumen) to the ensiling process exists. Thus image textural features seemed to give new and interesting measurements of the physical properties of the silage, explaining the biological response better than other methods. Furthermore, the ensiling effect was not the same with all the maize types and varied with the proportion of large particles in the silages. Linear relations between features before and after the ensiling process made it possible to predict a measure on a silage knowing its value on the parent forage. Copyright © 2004 Society of Chemical Industry 相似文献
23.
Wood inspection with non-supervised clustering 总被引:9,自引:0,他引:9
Abstract. The appearance of sawn timber has huge natural variations that the human inspector easily compensates for mentally when determining
the types of defects and the grade of each board. However, for automatic wood inspection systems these variations are a major
source for complication. This makes it difficult to use textbook methodologies for visual inspection. These methodologies
generally aim at systems that are trained in a supervised manner with samples of defects and good material, but selecting
and labeling the samples is an error-prone process that limits the accuracy that can be achieved. We present a non-supervised
clustering-based approach for detecting and recognizing defects in lumber boards. A key idea is to employ a self-organizing
map (SOM) for discriminating between sound wood and defects. Human involvement needed for training is minimal. The approach
has been tested with color images of lumber boards, and the achieved false detection and error escape rates are low. The approach
also provides a self-intuitive visual user interface.
Received: 16 December 2000 / Accepted: 8 December 2001
Correspondence to: O. Silvén 相似文献
24.
25.
S. Zaefferer 《Advanced Engineering Materials》2003,5(8):607-613
In recent years the investigation of local texture and microstructure by analysis of electron backscatter diffraction patterns (EBSP) in the SEM has become a very powerful and popular method. With the introduction of SEM with field emission guns (FEG) the spatial resolution of EBSP measurements could be enhanced from 500 nm with a tungsten emitter to better than 50 nm. This evolution of SEM techniques raises the question whether transmission electron microscopy (TEM) still has fields of application in texture research. The present article answers this question with a clear “yes” and presents three examples of investigations where TEM is indispensable. The three examples comprise the investigation of the correlation between dislocation structure and deformation texture, a study on nucleation mechanisms of recrystallization in highly deformed metals and the investigation of microtexture and microstructure in nanocrystalline materials. Together with the presentation of these cases some of the necessary measurement techniques are described briefly. It is shown that TEM has to be applied when highest spatial resolution of orientation determination and imaging and high accuracy of orientation determination are to be reached, when the three‐dimensional and quantitative characterization of lattice defects is required or when materials with a high density of lattice defects are to be investigated. 相似文献
26.
Real-time homogenous translucent material editing 总被引:4,自引:0,他引:4
This paper presents a novel method for real-time homogenous translucent material editing under fixed illumination. We consider the complete analytic BSSRDF model proposed by Jensen et al. [ [JMLH01] ], including both multiple scattering and single scattering. Our method allows the user to adjust the analytic parameters of BSSRDF and provides high-quality, real-time rendering feedback. Inspired by recently developed Precomputed Radiance Transfer (PRT) techniques, we approximate both the multiple scattering diffuse reflectance function and the single scattering exponential attenuation function in the analytic model using basis functions, so that re-computing the outgoing radiance at each vertex as parameters change reduces to simple dot products. In addition, using a non-uniform piecewise polynomial basis, we are able to achieve smaller approximation error than using bases adopted in previous PRT-based works, such as spherical harmonics and wavelets. Using hardware acceleration, we demonstrate that our system generates images comparable to [ [JMLH01] ]at real-time frame-rates. 相似文献
27.
Graziella Tonfoni 《Artificial Intelligence Review》1996,10(3-4):187-208
CPP-TRS (Tonfoni 1989–94) is both a methodology and a language. Through the methodology (CPP — Communicative Positioning Program) those invisible aspects of communication are identified and represented by the meta-language (TRS — Text Representation Systems), which complements natural language. CPP-TRS is a new paradigm which applies to any communicative context.Icons in CPP-TRS are not intended to represent words or sentences in order to substitute them; they are rather intended to represent visually what natural language does not convey naturally. The improvement of communication is a challenge of the present and the future: CPP-TRS is designed explicitly for it.The CPP-TRS system thus is able to support the user with a set of visual tools, that are specifically suited to structuring text and communicating effectively.The same tools can support communication very effectively in situations where ambiguity can highly compromise the final result.The system may be used in a way that is either opaque or transparent to the reader of the text.Author of CPP-TRS¢ and CPP-TRS¢ Applications Designer. 相似文献
28.
Simulation of polycrystalline aluminum tensile test with crystal plasticity finite element method 总被引:1,自引:0,他引:1
The crystal plasticity was implemented in the finite element method(FEM) software ABAQUS through the user subroutine UMAT. By means of discretizing the space at the grain level with the Voronoi diagram method, a polycrystal model was built and used in the FEM analysis. The initial orientation of each grain was generated based on the orientation distribution function(ODF). The developed model was successfully applied in simulation of polycrystalline aluminium samples deformed by the tensile tests. The theoretical strain--stress relation was in good agreement with the experimental result. The simulation results show that the grain size has significant effect on the deformation behavior. The initial plastic deformation usually occurs at grain boundaries, and multiple slip often results in an enhanced local hardening at grain boundaries. 相似文献
29.
30.
Nie Zuoren Zhang Xinming Yin Zhimin Department of Materials Science Engineering Central South University of Technology Changsha 《中国有色金属学会会刊》1997,(3)
MICROSTRUCTURESANDTEXTURESINCOLDROLLEDALUMINIUMSTRIP①NieZuoren,ZhangXinming,YinZhiminDepartmentofMaterialsScienceandEngineri... 相似文献