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1.
It is necessary to determine the accurate reflectance of painted surfaces for the review of paint finishes by computer graphics (CG) before actual painting of the exterior color of automobiles, and for quality control during production and inspection processes. We have optimized a method for measuring reflectance by using a statistical technique. We have found that the reflectance of a painted surface is best measured at an incident angle of 60° and at five aspecular angles of 10°, 18°, 28°, 40°, and 90°. Our method makes it possible to accurately reproduce reflection characteristics of paint finishes containing special flake pigments, such as pearl mica. Also it was proved that our method can apply not only to solid and metallic coatings but to all painted surfaces. © 2005 Wiley Periodicals, Inc. Col Res Appl, 30, 275–282, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.20125 相似文献
2.
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
3.
Abstract. This article proposes an extension to scalar component methodology for the identification and estimation of VARMA models. The complete methodology determines the exact positions of all free parameters in any VARMA model with a predetermined embedded scalar component structure. This leads to an exactly identified system of equations that is estimated using full information maximum likelihood. 相似文献
4.
Fourteen commercial polyadipates and a polysebacate were analysed for their components of a molecular mass below 1000 Da, primarily with the aim of generating the background data for measuring the migration of this type of polymeric additives from plasticized PVC (e.g. cling films and gaskets of lids) into foods or food simulants. Since the composition of the material <1000 Da varies between the polyadipates, the main components must be identified to enable a correct quantification. Polyadipates differ in the diol used as linker, their termination (acid or alcohol) and in the end‐capping (free alcohols, acetylation, acylation with fatty acids, esterification with octanol/decanol). Gas chromatography (GC) provides good separation, but the material remaining in the column up to high temperatures decomposes and forms a hump in the rear part of the chromatogram. Examples of mass spectra are shown, the most indicative fragments pointed out and spectra of 159 components listed. The polyadipates and the sebacate are characterized by their structure, the main components <1000 Da and the fraction of material <1000 Da. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
5.
湿浸法制备活性组分非均匀分布负载型催化剂过程的计算机模拟 总被引:1,自引:0,他引:1
对活性组分非均匀分布的负载型催化剂的湿浸法制备过程进行了计算机模拟,其模拟程度可适用于任意多个活性组分的浸渍。发现单组分浸渍时,通过控制浸渍时间可获得活性组分由薄到厚的蛋壳型分布和均匀分布,但通过预浸渍吸附至一定分布后,再在空白溶液中浸渍洗脱,控制洗脱条件也可获得蛋黄、蛋白型的分布;加入竞争吸附剂,进行双组分及多组分浸渍,通过控制浸渍溶液性质及浸渍时间可获得各种类型的活性组分分布,诸如蛋壳型、蛋白型、蛋黄型和均匀型。通过对制备过程参数(如竞争吸附剂的选择、各组分有效扩散系数、初始浓度、吸脱附速率常数等)与活性组分分布形式之间关系的分析,可实现对任一分布形式的催化剂的制备过程参数的优化。这对实际制备催化剂具有指导意义。 相似文献
6.
Coordination components for collaborative virtual environments 总被引:1,自引:0,他引:1
Alberto B. Raposo Adailton J. A. da Cruz Christian M. Adriano Lo P. Magalhes 《Computers & Graphics》2001,25(6):1025-1039
This paper deals with the behavior of virtual environments from the collaboration point-of-view, in which actors (human or virtual beings) interact and collaborate by means of interdependent tasks. In this sense, actors may realize tasks that are dependent on tasks performed by other actors, while the interdependencies between tasks (through resource management and temporal relations) delineate the overall behavior of a virtual environment. Our main goal is to propose an approach for the coordination of those behaviors. Initially a generic study of possible interdependencies between collaborative tasks is presented, followed by the formal modeling (using Petri Nets) of coordination mechanisms for those dependencies. In order to implement such mechanisms, an architecture of reusable and pluggable coordination components is also introduced. These components are used in an implementation of a multi-user videogame. The presented approach is a concrete step to create virtual societies of actors that collaborate to reach common goals without the risk of getting involved in conflicting or repetitive tasks. 相似文献
7.
It has been confirmed that adult virgin females ofAnthrenus sarnicus Mroczkowski exhibit a characteristic headstand posture that is associated with the release of a sex pheromone. Volatiles trapped on filter papers suspended above calling females were attractive to adult virgin males when tested in a two-choice target bioassay. Separate aeration extracts of males and females were analyzed by gas chromatography-mass spectrometry and showed that decanol and decyln-butyrate were released by females only. These components were present in approximately equal amounts and accounted for about 90% of the total area of the chromatogram. Decyl butyrate produced an electroantennogram response with a larger response from males than females. Behaviorally, a mixture of 10g of decanol and 10g of decyl butyrate attracted 88% of males and 10g of decyl butyrate alone attracted 82% of males in the bioassay. The role of decyl butyrate as a sex pheromone is convincing, but this is not the case for decanol. 相似文献
8.
Disruption damage conditions for future large tokamaks like ITER are nearly impossible to simulate on current tokamaks. The electrothermal plasma source SIRENS has been designed, constructed, and operated to produce high density (> 1025/m3), low temperature (1–3 eV) plasma formed by the ablation of the insulator with currents of up to 100 kA (100 s pulse length) and energies up to 15 kJ. The source heat fluence (variable from 0.2 to 7 MJ/m2) is adequate for simulation of the thermal quench phase of plasma disruption in future fusion tokamaks. Different materials have been exposed to the high heat flux in SIRENS, where comparative erosion behavior was obtained. Vapor shield phenomena has been characterized for different materials, and the energy transmission factor through the shielding layer is obtained. The device is also equipped with a magnet capable of producing a parallel magnetic field (up to 16 T) over a 8 msec pulse length. The magnetic field is produced to decrease the turbulent energy transport through the vapor shield, which provides further reduction of surface erosion (magnetic vapor shield effect). 相似文献
9.
Software release management is the process through which software is made available to and obtained by its users. Until now, this process has been relatively straightforward. However, the emergence of component‐based software is complicating software release management. Increasingly, software is constructed via the assembly of pre‐existing, independently produced, and independently released components. Both developers and users of such software are affected by these complications. Developers need to accurately document the complex and changing dependencies among the components constituting the software. Users must be involved in locating, retrieving, and assembling components in order to appropriately bring the software into their particular environment. In this paper, we introduce the problem of release management for component‐based software and discuss SRM, a prototype software release management tool we have developed that supports both developers and users in the software release management process. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
10.
A combined 2D numerical-analytical algorithm for electromagnetic (EM) fields computation in one-counter waveguides with arbitrary cross section is proposed. The developed algorithm is employed to investigate the influence of the normalized propagation constant and dielectric loading on the field distribution in a rectangular T-septum waveguide with an E-plane dielectric insert. Dominant-mode varieties of a given transmission line are represented. © 2004 Wiley Periodicals, Inc. Int J RF and Microwave CAE 14, 201–205, 2004. 相似文献