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91.
92.
We present a multiresponse estimation procedure for parameters of systems described by ? = As. The procedure features a generalized Gauss–Newton algorithm for optimizing the determinant criterion, efficient evaluation of the expectation function and its derivatives directly from the reaction network or compartment diagram, automatic determination of starting values, and eficient computational procedures for handling linear constraints on the responses. 相似文献
93.
94.
Abstract The performance of a nonlinear joint transform correlator which employs a GEC-Marconi optically addressed spatial light modulator in the Fourier plane is investigated in terms of the device operating conditions and other system parameters. We discuss the optimum performance characteristics of the correlator and the sensitivity to changes in the rotation, scale and separation of the objects in the input plane. 相似文献
95.
The design of a novel multi-electrode electromagnetic flowmeter, which provides nine conventional electromagnetic flowmeters housed in a single body, has been used in adverse flow conditions immediately downstream from a header tank. The results show that careful initial calibration, in accord with the pipeline conditions recommended in international standards, enables errors of under 1% to be achieved. The results show that the two electrode planes closest to the header provide results with the greatest errors. The performance with the electrodes mounted in the vertical plane is generally better than that achieved with the electrodes mounted in the horizontal plane. Pressure measurements together with laser Doppler anemometry (LDA) and particle image velocimetry (PIV) techniques have been used to provide details of the magnitude of the disturbance caused to the flow field by the header and outflow combination. 相似文献
96.
New approach to metamerism measurement on halftone color images 总被引:2,自引:0,他引:2
There is often a phenomenon depending on dominant tones which results in the end users dissatisfaction with halftone color reproduction. This phenomenon is known as “metamerism” and it is the subject of research for many scientists.The metamerism on halftone color images with different dominant tones (blue, red, green and yellow) was researched in this paper, at the light sources D50, D65 and daylight. The results of the objective and visual evaluation were presented on the basis of colorimetric measurement of the grey balance patch, by the means of MacAdam ellipsoids in three dimension CIE L*a*b* system. Both the metamerism index MI and the ellipsoid volume have also been calculated.This paper confirms that the metamerism of the halftone color images can be estimated by measuring CIE L*a*b* values of the grey balance patch and by calculating MacAdam ellipsoids. 相似文献
97.
A. V. Sverdlin G. E. Totten C. Bates L. M. Jarvis 《Metal Science and Heat Treatment》1996,38(6):248-251
The development of methods for evaluating and predicting the variation of the properties of polymer quenching media in operation requires an analysis of the quenching factor, which characterizes the degree of decomposition of the solid solution in quenching, which decreases the strength (hardness) of the alloy by a given value. In the present paper the quenching factorQ is used to compare the properties of aluminum alloys quenched in hot water and aqueous solutions of polymers.Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 6, pp. 14 – 17, June, 1996. 相似文献
98.
Laboratory activated sludge systems were operated at various COD:P ratios to study the effects of the influent phosphorus concentration on COD removal efficiency, cellular phosphorus, carbohydrate and protein contents, and alkaline phosphatase activity. In varying the COD:P ratio, the COD was held constant at 1000 mg l−1 and phosphorus concentrations of 1, 2, 3, 5, 7, 9, 10, 20, 35 and 50 mg l−1 were used. The optimum COD:P ratio for this study was found to be 100:1. Increasing the phosphorus concentration in the influent above one percent of the influent COD did not provide for an increase in the COD removal nor for significant changes in the cellular protein and carbohydrate content or the alkaline phosphatase activity. 相似文献
99.
Sherry Bates 《The Journal of Architecture》2013,18(1):75-86
This paper compares two forms of representation of cities: the drawings of the urban designer and the photographs of the tourist guidebook or brochure. Both forms of representation reveal two often opposing value systems and each may offer only a restricted view of what the attractions of a city might be. The tourist industry's ‘imagineering’ is excluded from ‘urban design’. Yet the city on the ground and its popular image are entities in whose design the tourist industry plays a major role … 相似文献
100.
With the aim of seeking an alternative low-cost process for the fabrication of MCrAlY coatings, an electrolytic co-deposition process was employed to form a composite coating consisting of a Ni matrix and CrAlY particles. Three configurations were investigated in the co-deposition process, including a vertical setup, a horizontal arrangement, and a rotating barrel. The CrAlY volume fractions in the resultant composite coatings were compared. The advantages and disadvantages of each configuration were discussed. Among the three configurations studied in this paper, the rotating barrel demonstrated the best overall performance, with the capability of producing coatings with more uniform CrAlY particle incorporation of up to 40 vol.%. 相似文献