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11.
Multimedia Tools and Applications - Emotions are spontaneous feelings that are accompanied by fluctuations in facial muscles, which leads to facial expressions. Categorization of these facial...  相似文献   
12.
Expanded gamut printing is an approach in color reproduction that expands the color gamut of conventional CMYK printing processes via the use of additional colorants, such as Orange, Green, and Violet inks. This study evaluates the ability of commercial color management software to create an accurate solution for an expanded gamut printing system. In this study, two printing processes were used, an Epson SureColor P9000 inkjet printer/proofer and an HP Indigo 7900 digital production press, both with 7-color expanded gamut ink sets. Software solutions from Alwan, CGS ORIS, ColorLogic, GMG Color, Heidelberg, and Kodak were evaluated. The systems were tested to see how well they could reproduce the colors in the entire PANTONE+ Solid Coated spot color library. It is shown that the solutions are able to reproduce 89% to 94% of the spot colors on the Epson P9000 inkjet printer and 77% to 87% of the library on the Indigo 7900, both to less than two CIEDE2000 (a typical tolerance in label and packaging work). The number of color patches in expanded gamut characterization test charts was noted, as this is still an area of proprietary, nonstandardized working practice. There are many different colorant combinations that can make the same color in expanded gamut printing. The ink build created by the different software solutions was studied, as it relates to press stability through appropriate choice of colorants. Pantone and Adobe provide everyday commercial tools for expanded color workflows. The study identified some issues with products from these companies that could confuse a less-skilled user in a busy production environment. The conclusion of the study is that expanded gamut solutions for spot color printing produce totally acceptable results for digital printing processes; expanded gamut printing is ready, here and now. The findings show that expanded gamut printing can replace cumbersome conventional spot color workflows creating considerable savings and advantages, especially for label and packaging printers.  相似文献   
13.
FeO-doped TiO2 nanoparticle photocatalysts were immobilized onto the surface of fibrous activated carbon (ACF) via a sol-gel process. As an adsorbent and photocatalyst, FeO-TiO2 on immobilized ACFs (FeO-TiO2/ACF) greatly improved the photocatalysis rate of hydrogen production as compared with pure TiO2 and ACF-TiO2 under UV irradiation and visible light. The addition of ACFs surface significantly reduced the photogenerated pairs of electrons-hole recombination, thereby promoting the photocatalysis action of doped photo-metal oxides of FeO-TiO2. Co-doping of FeO onto the lattice of the TiO2 approach can improve the absorption activity of visible light through photo-metal oxide of TiO2 and further enhance hydrogen production under visible light. The photocatalytic fabrics (FeO-TiO2/ACF) were effortlessly split out from the experimental solution for re-utilization and exhibited high stability even after five complete regeneration cycles.  相似文献   
14.
Clean Technologies and Environmental Policy - Manufacturing organizations are under continuous pressure to implement sustainability in their activities. There is a need to identify the...  相似文献   
15.
Improving the performance of heat transfer fluids is altogether significant. The best approach for improving the thermal conductivity is the addition of nanoparticles to the base fluid. In the present study, specific heat, dynamic viscosity, and thermal conductivity of water-based Indian coal fly ash stable nanofluid for 0.1% to 0.5% volume concentration in the temperature range of 30 to 60°C has been investigated. To evaluate an average particle diameter of 11.5 nm, the fly ash nanoparticles were characterized with scanning electron microscopy and dynamic light scattering. Using zeta potential, the stability of nanofluid in the presence of surfactant Triton X-100 was tested. Thermal conductivity and viscosity of fly ash nanofluid increased, while specific heat decreased as volume concentration increased. The effect of temperature on the fly ash nanofluid was directly proportional to its thermal conductivity and specific heat and inversely proportional to viscosity.  相似文献   
16.
Variable rate speech coding is now recognized as an important system component for high-capacity cellular networks because it exploits speech statistics to reduce the average bit rate, which results in reduced interference and increased capacity. Once a variable rate capability is available, an additional capacity enhancement can be achieved by introducing network control of the user bit rate in response to changing traffic levels. We introduce the concept of network control of rate and propose a particular network-control method for code-division multiple access (CDMA) systems. Based on an M/M/∞//M queueing model applied to a cell under heavy traffic conditions and a new performance measure called averaged speech quality, we obtain simulation results to demonstrate how network control of rate can achieve improved speech quality or increased capacity for a given quality objective  相似文献   
17.
A genetic linkage map of human chromosome 21q (HC21q) containing 43 markers genotyped by the polymerase chain reaction in the CEPH pedigrees is presented. The markers placed on this map are highly polymorphic with an average heterozygosity of 61%. The average interval size of the markers localized at 1000:1 odds is 2.5 cM. The map has a total length of 65.5 cM, with male and female lengths of 47.7 and 83.3 cM, respectively. The genotypes used in the construction of this map were subjected to rigorous error checking, which is reflected in the shorter map length compared to previous maps; the estimated error rate in genotyping is less than 0.04%. As noted in previous linkage maps there is increased recombination in females on proximal HC 21q and in the male in a region near the telomere. This map of HC 21 represents a highly informative and dense meiotic linkage map and will be useful in linking disease phenotypes to loci on this chromosome.  相似文献   
18.
This paper demonstrates the use of computer simulation for topological design and performance engineering of transparent wavelength-division multiplexing metropolitan-area networks. Engineering of these networks involves the study of various transport-layer impairments such as amplifier noise, component ripple, chirp/dispersion, optical crosstalk, waveform distortion due to filter concatenation, fiber nonlinearities, and polarization effects. A computer simulation methodology composed of three main simulation steps is derived and implemented. This methodology obtains performance estimations by applying efficient wavelength-domain simulations on the entire network topology, followed by time-/frequency-domain simulations on selected paths of the network and finally Q-budgeting on an identified worst case path. The above technique provides an efficient tool for topological design and network performance engineering. Accurate simulation models are presented for each of the performance impairments, and the computer simulation methodology is used for the design and engineering of a number of actual metro network architectures  相似文献   
19.
传统制导弹药自动驾驶仪的设计要求精确的气动模型,并依赖于变增益(gainschedule),以说明系统的非线性.本文给出了一种简化自动驾驶仪设计程序的方法:在单一飞行条件下设计逆控制器,将逆控制器与在线神经网络组合,以说明因近似逆引起的误差,这样减少了大量设计程序及精确的气动数据.这些数据在大攻角或其它情况下很重要,因为这些领域中的空气动力特征变得高度非线性化.研究发现:逆的选择在其实现的过程中很重要,所以详细讨论.最后,给出该方法在非线性6自由度制导弹药中的模拟结果.  相似文献   
20.
The bulk copolymerization of styrene–acrylonitrile monomers using styrene‐N+–montmorillonite complex as a comonomer in the polymerization was studied. The X‐ray diffraction (XRD) analysis showed that part of the styrene‐N+–montmorillonite complex remained non‐dispersed (immiscible) and the copolymer was excluded from the interlayer of the immiscible part of the clay. The successive chemical extraction process revealed that a reasonable amount of the styrene–acrylonitrile copolymer was directly attached to the styrene‐N+–montmorillonite complex and enveloped the clay. Highly exfoliated clay lamella and nanospheres (3–5 nm) were observed by transmission electron microscopy (TEM). The montmorillonite clay assume two different morphologies, immiscible and exfoliated, on the basis of the XRD and TEM data. A simple method of calculation of the ratio of the exfoliated/immiscible amounts of the clay indicated that the amount of the styrene‐N+–montmorillonite complex exfoliated into separate lamella was 40 % (w/w) of the amount of the clay samples containing 2 % of the (styrene‐N+–montmorillonite complex) clay. This amount of exfoliated clay decreases with the increase of the concentration of the clay. The presence of the styrene‐N+–montmorillonite clay in the copolymerization reaction had a minor effect on both the copolymer composition and the molecular weight. Modification of the clay with the derivatized styrene monomer can achieve a nanocomposite using a percentage no more than 4 % (w/w) of complex in the copolymer. Copyright © 2004 Society of Chemical Industry  相似文献   
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