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11.
Control charts are usually implemented in two phases: the retrospective phase (phase I) and the monitoring phase (phase II). The performance of any phase II control chart structure depends on the preciseness of the control limits obtained from the phase I analysis. In statistical process control, the performance of phase I dispersion charts has mainly been investigated for normal or contaminated normal distributions of the quality characteristic of interest. Little work has been carried out to investigate the performance of a wide range of possible phase I dispersion charts for processes following non‐normal distributions. The current study deals with the proper choice of a control chart for the evaluation of process dispersion in phase I. We have analyzed the performance of a wide range of dispersion control charts, including two distribution‐free structures. The performance of the control charts is evaluated in terms of probability to signal, under normal and non‐normal process setups. These results will be useful for quality control practitioners in their selection of a phase I control chart. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
12.
The logistics of the fuel supply have a large impact on the economy of a biomass power generation facility, especially for low density biomass fuels like straw. A detailed cost analysis of a typical rice straw logistics process for two baling options in three regions of Thailand shows that the costs for all logistics operations vary from a minimum of 18.75 USD/t for small rectangular bales in the Northern region of Thailand to maximum 19.89 USD/t for large rectangular bales in the North-eastern region. The difference in costs is not very significant due to the higher ownership and operating costs of the equipment for using large rectangular bales; however, the specific fuel consumption cost is substantially lower by around 17.5% and a total transport cost reduction is about 31.5%. Analysis of the logistics economies of scale for projected power plant capacities of 2-35 MWe showed that each doubling the capacity of the energy facility increases the specific costs of the logistics operations only by around 4% in all regions.  相似文献   
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A study is made of the propagation of plane electro-magneto-thermo-visco-elastic harmonic waves in an unbounded isotropic conducting visco-elastic medium of Kelvin–Voigt type permeated by a primary uniform magnetic field when the entire medium rotates with a uniform angular velocity. The thermal relaxation time of heat conduction, the electric displacement current, the coupling between heat flow density and current density, and that between the temperature gradient and the electric current are included in the analysis. A more general dispersion relation is obtained to determine the effects of rotation, thermal relaxation time, visco-elastic parameters, and the external magnetic field on the phase velocity of the waves. Perturbation techniques are used to study the influence of small magneto-elastic and thermo-elastic couplings on the phase velocity of the waves. Cases of low and high frequencies are also analyzed to determine the effect of rotation, visco-elastic parameters, thermo elastic and magneto-elastic coupling, as well as thermal relaxation time of heat conduction on the waves.  相似文献   
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Microsystem Technologies - Electronic devices are shrinking day by day, while the speed and reliability is increasing. At the same time, IC designs and micro/nano electronic systems are becoming...  相似文献   
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In the context of the world's energy crisis and environmental concerns, crop-based ethanol has emerged as an energy alternative, the use of which can help reduce oil imports as well as emissions of CO2 and other air pollutants. However, a clear disadvantage of ethanol is its high cost over gasoline under the current pricing scheme that does not include externalities. The intent of this study is to perform a life cycle analysis comparing environmental and cost performance of molasses-based E10 with those of CG. The results show that although E10 provides reduction in fossil energy use, petroleum use, CO2 and NOx emissions, its total social costs are higher than those of gasoline due to higher direct production costs and external costs for other air emissions, e.g. CH4, N2O, CO, SO2, VOC and PM10. An analysis of projection scenarios shows that technological innovations towards cleaner production help maximize ethanol's benefits whilst minimizing its limitations.  相似文献   
17.
Glidant and lubricant efficiencies of a number of different types of talcs were evaluated. The in vitro properties of tablets lubricated with talcs were compared to those lubricated with magnesium stearate. Talc lubricated tablets showed superior in vitro properties compared to magnesium stearate lubricated tablets. Different sources of talcs showed significant differences in glidant and lubricant efficiencies.  相似文献   
18.
Building enclosures contribute 10–50% of the total building cost and 14–17% of the total material mass. The direct as well as indirect influence of the enclosure materials plays an important role in the building life cycle energy. Single landed houses, the typical houses in Indonesia, have been chosen for this study. The life cycle energy of the house enclosures and energy consumed during their life spans shows intriguing results. The initial embodied energy of typical brick and clay roof enclosures is 45 GJ compared to the other typical walls and roof material (cement based) which is 46 GJ. However, over the 40 years life span of the houses, the clay based ones have a better energy performance than the cement based ones, 692 GJ versus 733 GJ, respectively. The material selection during the design phase is thus crucial since the buildings have at least 40–50 years’ life span.  相似文献   
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Image fusion has been receiving increasing attention in the research community with the aim of investigating general formal solutions to a wide spectrum of applications such as multifocus, multiexposure, multispectral ( $IR$ -visible) and multimodal medical (CT and MRI) image and video fusion. While there exist many fusion techniques for each of these applications, it is difficult to formulate a common fusion technique that works equally well for all these applications. This is mainly because of the different characteristics of the images involved in various applications and the correspondingly different requirements on the fused image. In this work, we propose a common generalized fusion framework for all these classes, based on the statistical properties of local neighborhood of a pixel. As the eigenvalue of the unbiased estimate of the covariance matrix of an image block depends on the strength of edges in that block, we propose to employ it to compute a quantity we call as the significance of a pixel. This generalized pixel significance in turn can be used as a measure of the useful information content in that block, and hence can be used in the fusion process. Several data sets were fused to compare the results with various recently published methods. The analysis shows that for all the image types into consideration, the proposed methods improve the quality of the fused image, both visually and quantitatively, by preserving all the relevant information.  相似文献   
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