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101.
We propose a composite multivariate quality control (CMQC) system to control simultaneously measured variables. This system is designed to detect unacceptable trends and systematic error in one or more variables, unacceptable random error in one or more variables, and unacceptable changes in the correlation structure in any pair of variables. It is also designed to be tolerant of missing data, to be capable of rejecting as few as one or as many as all variables in a run, and to provide the analyst with control statistics and graphics that logically relate to sources of analytical error. Quality control rules for univariate, multivariate, and correlation conditions are incorporated in the system, as are plots displaying CMQC statistic values and control limits for univariate, multivariate, and correlation parameters. We also discuss advantages of the CMQC over the T2 and principal component multivariate quality control methods. We demonstrate the CMQC procedure using data from a laboratory process in which 40 variables were measured during 40 characterization runs and 23 runs analyzing unknowns. 相似文献
102.
Ken Smith 《Color research and application》2007,32(4):249-255
This study describes a process of relating the perceptual analysis of the colors of the terrestrial atmosphere to currently available pigments used in artists' painting systems. This process sought to discover how the colors of the sky could be defined and simulated by these pigments. The author also describes how confusion over the bewildering choice of suitable pigments on offer in the market place can be clarified. © 2006 Wiley Periodicals, Inc. Col Res Appl, 32, 249–255, 2007 相似文献
103.
A difficulty in reliability modeling is how to capture the impact of all of the various reliability defect types. The general approach to optimizing burn-in that we describe in this article addresses a multiple-defect environment. The approach has four main parts: (i) modeling the product's failure rate distribution, (ii) establishing the Pareto distribution of reliability defects, (iii) assessing the kinetic information of each reliability defect, and (iv) estimating the DPPM under product use conditions. This article compares and contrasts the acceleration effects of various extrinsic defects found in 130- and 90-nm CMOS technology products. 相似文献
104.
Several railgun experiments designed to accelerate projectile masses of 2 to 5 g to velocities greater than 6 km/s were performed. Two parallel rail-type accelerators with 12.7 mm square bores were used for the experiments. One gun is 2 m long, has molybdenum rails and alumina ceramic insulators. The other is 1 m long, has molybdenum rails and granite insulators. The greatest velocity achieved to date during the experiments was 5.1 km/s. During the test program, the following ideas to enhance launcher performance were tested: stiff-gun structures to reduce plasma leakage and rail movement, refactory bore materials to reduce ablation and frictional losses, and prefilling the gun bore with gases which will eliminate precursor arcs. After three experiments utilizing the 2 m long launcher, with peak currents ranging from 660 to 780 kA, a gun barrel comprised of 96% pure alumina ceramic insulators and 99.9% pure molybdenum rails has survived with minimal damage and no degradation of seals 相似文献
105.
Becker D. Vaughn; Kenrick Douglas T.; Neuberg Steven L.; Blackwell K. C.; Smith Dylan M. 《Canadian Metallurgical Quarterly》2007,92(2):179
Findings of 7 studies suggested that decisions about the sex of a face and the emotional expressions of anger or happiness are not independent: Participants were faster and more accurate at detecting angry expressions on male faces and at detecting happy expressions on female faces. These findings were robust across different stimulus sets and judgment tasks and indicated bottom-up perceptual processes rather than just top-down conceptually driven ones. Results from additional studies in which neutrally expressive faces were used suggested that the connections between masculine features and angry expressions and between feminine features and happy expressions might be a property of the sexual dimorphism of the face itself and not merely a result of gender stereotypes biasing the perception. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
106.
Enteric viral infections of calves and passive immunity 总被引:6,自引:0,他引:6
At least eight viruses have been identified, four within the last 5 yr, that produce diarrhea and pathological intestinal lesions in experimentally inoculated calves. Coronavirus and rotavirus frequently are associated with the neonatal calf diarrhea syndrome, but the etiologic role of the newly identified viruses is undefined. All diarrheal viruses replicate within small intestinal epithelial cells, resulting in variable degrees of villous atrophy. Immunity against these viral infections, therefore, must be directed toward protection of the susceptible intestinal epithelial cells. Because most of these viral infections occur in calves less than 3 wk of age, passive lactogenic immunity within the gut lumen plays an important role in protection. This report reviews methods of boosting rotavirus antibody responses in bovine mammary secretions and analyses of passive and active immunity in calves supplemented with colostrum and challenged by rotavirus. Results indicate rotavirus immunoglobulin G1 antibodies in colostrum and milk were elevated after intramuscular and intramammary vaccination of pregnant cows with an Ohio Agricultural Research and Development Center rotavirus vaccine but not after intramuscular immunization with a commercial rota-coronavirus vaccine. Feeding colostrum from intramuscular plus intramammary immunized cows to newborn calves challenged by rotavirus prevented diarrhea and shedding of rotavirus. 相似文献
107.
108.
DePriest C.M. Yilmaz T. Braun A. Abeles J. Delfyett P.J. Jr. 《Quantum Electronics, IEEE Journal of》2002,38(4):380-389
We report on the development of an ultralow-noise, external-cavity, actively mode-locked semiconductor diode laser for application in next-generation photonic sampling systems. A summary of harmonically mode-locked noise characteristics in a 65-MHz ring cavity is presented through the range of pulse repetition frequencies between 130 MHz and 8.3 GHz (2nd-128th harmonic). Important implications regarding the use of gain-versus-loss modulation as the active modelocking mechanisms are discussed. We also report what are, to our knowledge, the lowest noise characteristics achieved to date for a semiconductor diode laser operating at 10 GHz. Individually optimized results of 0.12% rms amplitude noise (10 Hz-10 MHz), and 43 fs rms residual phase jitter (10 Hz-10 MHz) provide a theoretical resolution of 8.6 bits in a 10-GSPS optical analog-to-digital converter. We have also achieved dispersion-compensated pulsewidths; as short as 1.2 ps, and shown successful operation of a novel phase-locked-loop capable of reducing the rms; residual phase noise by as much as 91% within its response bandwidth. Finally, the first measurements of residual phase noise out to the Nyquist frequency (5 GHz) are presented, providing an upper bound on the rms residual phase jitter of 121 fs (10 Hz-5 GHz) 相似文献
109.
To improve a company's 'chopping' power it is necessary to apply systems engineering principles to 'project systems' and take the time to plan effectively, to reflect upon what it is that is being done and thereby improve the way things are done. This article takes a systems view of the project and applies systems engineering principles to project management. Projects (complex systems) are needed to create deliverables (which are also complex systems) and investing in the former will be more than paid back in the latter. It is our aim here to clear up some misunderstandings about systems engineering and its role within a complex project and to highlight the need for businesses to take time to improve their processes in the context of good systems engineering practice. 相似文献
110.