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11.
Visual evaluation experiments of color discrimination threshold and suprathreshold color‐difference comparison were carried out using CRT colors based on the psychophysical methods of interleaved staircase and constant stimuli, respectively. A large set of experimental data was generated ranged from threshold to large suprathreshold color difference at the five CIE color centers. The visual data were analyzed in detail for every observer at each visual scale to show the effect of color‐difference magnitude on the observer precision. The chromaticity ellipses from this study were compared with four previous published data, of CRT colors by Cui and Luo, and of surface colors by RIT‐DuPont, Cheung and Rigg, and Guan and Luo, to report the reproducibility of this kind of experiment using CRT colors and the variations between CRT and surface data, respectively. The present threshold data were also compared against the different suprathreshold data to show the effect of color‐difference scales. The visual results were further used to test the three advance color‐difference formulae, CMC, CIE94, and CIEDE2000, together with the basic CIELAB equation. In their original forms or with optimized KL values, the CIEDE2000 outperformed others, followed by CMC, and with the CIELAB and CIE94 the poorest for predicting the combined dataset of all color centers in the present study. © 2005 Wiley Periodicals, Inc. Col Res Appl, 30, 198–208, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.20106 相似文献
12.
分析了电石法PVC生产链中电石炉烟气及电厂烟气二氧化硫的排放情况,指出利用电石炉烟气中的CO合成氨、再将合成氨用于燃煤电厂烟气的"氨法"脱硫是具有较大应用潜力的循环经济产业链。 相似文献
13.
Injun Lee Taeseong Jung Junggi Kim Suho Ro Chulsu Kim Yeji Lee Youngmi Kim Juhyun Lee Misook Kang 《Journal of Industrial and Engineering Chemistry》2008,14(6):869-873
This study focuses on the relationship between photo-catalytic performance and optical property over Si-incorporated TiO2. The Si-incorporated TiO2 particles exhibited a pure structure of anatase having a particle size of less than 20 nm and surface area of more than 190 m2/g. The absorbance did not shift to a higher wavelength in spite of the incorporation of the Si ions, but the intensity of the photoluminescence (PL) curve was the smallest in the case of the 2.0 mol% Si-TiO2, which was related to the recombination between the excited electrons and holes. Based on these results, the photodecomposition of methyl orange in the liquid reaction was enhanced over the 2.0 mol% Si-incorporated TiO2 compared with that over pure TiO2: Methyl orange at 10.0 ppm was completely decomposed after 100 min when 1.0 g of the 2.0 mol% Si-incorporated TiO2 was used. 相似文献
14.
对"比较法"原理和应用情况进行了分析,说明其在房地产开发中能够科学地预测房地产的价格和收益,从而提高财务分析的科学性和权威性,为项目决策提供科学依据,以促进"比较法"在房地产开发中的应用。 相似文献
15.
Residual stress as measured quantity in quality assurance The x‐ray method is used in the Volkswagen Automotive Group at different world‐wide locations as a standard procedure to determine residual stress. As an important measured quantity in the quality assurance residual stresses are specified in drawings of different components (e.g. gears, coil springs). Measurements are carried out during quality assurance, production, damage analyse, technical development department and design control of components from suppliers. An optimum efficiency can be achieved, if it exists a unique correlation between residual stress values and loading capacity of components, and if the processes to introduce residual stress can be optimized using residual stress measurements during the production. 相似文献
16.
结合兰州市的水泥标准稠度用水量方法测定 (代用法 )的实例 ,分析代用法测定标准稠度用水量的缺点 ,并对此方法提出了一些改进措施 相似文献
17.
Arash Sarhangi Fard Navid M. Famili Patrick D. Anderson 《Computers & Chemical Engineering》2008,32(7):1471-1481
The main objective of the present work is to modify the traditional mapping method for the simulation of distributive mixing of multiphase flows in geometries involving moving parts such as, internal mixers or twin-screw extruders without a limitation on their geometrical periodicity. The periodicity condition, limits the results of traditional mapping method to tracking mapping mesh between specific discrete time intervals or distances for that geometry is repeated, hence, result is only for fixed orientation of rotors. Imaginary domain method is introduced to track mapping mesh from one state to the next free of geometrical periodicity limitations. In this work the method is introduced and its applicability and accuracy is discussed in details. A two-dimensional (2D) simulation of mixing of two Newtonian fluids with different viscosities in an intermeshing internal mixer is used as a test case study. In this example the key issues of ability to predict mixing state in details for all orientations of rotors is presented. To reduce diffusion errors of mapping method in the boundaries of the rotors, mapping mesh refinement technique that relies upon one single reference mesh is also presented. 相似文献
18.
风管摩擦阻力的直接计算方法 总被引:2,自引:1,他引:1
提出用高精度的反映密度、黏度和温度关系的经验公式和Colebrook公式计算风管摩擦阻力系数的方法。分析和算例表明,用该方法计算,计算结果比采用常用工程设计方法更为准确,为应用计算机进行风道设计提供了直接、简便的方法。 相似文献
19.
This study develops a mathematical model for coupled heat and mass transfer in an unsaturated porous slab exposed to a flowing hot gas. Effects of the initial saturation conditions on associated variables, i.e., total pressure, temperature, moisture content, and multiphase flow, are studied. The Newton-Raphson method based on a finite volume technique is applied. This study emphasizes the influence of initial saturation level and gravitational effect in heat and multiphase flow phenomena associated with this system. Gravity enhances the downward flow of liquid within the porous slab. Pressure buildup occurs near the interface between the wet and the dry zone. However, it appears that the order of magnitude to the total pressure is small. This study explains the fundamental mechanism of multiphase flow that involves heat and mass transfer in a heated unsaturated porous slab. 相似文献
20.
We present a numerical study of the packing of uniform spheres under three-dimensional vibration using the discrete element method (DEM), focusing on the effects of vibration condition (amplitude and frequency) and inter-particle frictions (sliding and rolling frictions). The results are analysed in terms of packing density, coordination number (CN), radial distribution function (RDF) and pore structure. It is shown that increasing either the vibration amplitude or frequency causes packing density to increase initially to a maximum and then decrease. Both vibration frequency and amplitude should be considered to characterize the effect of vibration process on packing structure. The sliding and rolling frictions between particles can decrease packing density since they dissipate energy, although the effect of rolling friction is less significant. In line with the change of packing density, microstructural properties such as CN, RDF and pore distribution also change: a looser packing often corresponds to smaller CN, less peaked RDF and larger but more widely distributed pores. 相似文献