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931.
Alfredo Altuzarra José María Moreno-JiménezManuel Salvador 《European Journal of Operational Research》2007
This paper proposes a new priorization procedure for Analytic Hierarchy Process Group Decision Making (AHP-GDM). Unlike the methods normally employed in AHP-GDM, this process does not require intermediate filters for the actors’ initial judgements. The procedure is based on a Bayesian analysis of the problem and in general, it provides more efficient estimates than the techniques conventionally applied in the literature for AHP-GDM: aggregation of individual judgements (AIJ) and aggregation of individual priorities (AIP). The proposed procedure naturally extends to the analysis of incomplete and/or imprecise pairwise comparison matrices, enhancing realism, practicality and scope. The methodology has been illustrated by the analysis of a case study. 相似文献
932.
The scenario under consideration involves n cascaded continuous processing units responsible for processing m product lines. Each product line needs to be processed by all the units in the same sequence, and has dedicated finite capacity storage tanks before and after every processing unit. A unit can process only one product line at a time. Inputs for all the product lines arrive continuously and simultaneously on the input side of the first unit in the sequence. There are multiple intermediate due dates for the final products. An optimal schedule for the units calls for a trade-off among spillage costs, upliftment failure penalties and changeover costs. A mathematical model is developed for the purpose and the resulting MINLP is linearized using standard techniques. The MILP has been tested using GAMS for three units and three product lines as encountered in a refinery situation. The model could output optimal schedules for a ten day scheduling horizon within reasonable time. 相似文献
933.
Wang Fengyuand Yan Shijinn 《东北数学》1994,(2)
Order-preservationandPositiveCorrelationsforDiffusionProcessesonTorus¥WangFengyu(王凤雨)andYanShijinn(严士健)(DepartmentofMathemati... 相似文献
934.
A numerical model is developed to study the interactions of multiple angled jet flows in the inlet port plane of the Detroit Diesel 6V-92 two-stroke engine cylinder. The random vortex method is used in two dimensions. Results show axisymmetric swirl initially. As flow develops, the centre of the swirl moves to the mid-radius region and begins to precess about the cylinder centre. The flow becomes progressively more chaotic as time progresses. 相似文献
935.
Assume that a dam has a capacity V. Its water input I={It, t ? [0, ∞)}], is assumed to be a diffusion process. The water is released at one of two rates 0 and M units of water per unit of time. The release rate is 0 until the water reaches level λ(0 < λ < V), when the water is released at rate M until it reaches level λ, (0 ≤ τ < λ). Once the level λ is reached, the release rate remains at zero until level λ is reached again, and the cycle is repeated. Under general cost structure, we discuss and review some of the most recent work in the area of optimal control of dams with release policies of the above type; we also discuss some new results and corrections to some existing results. 相似文献
936.
937.
Separation of bulk lifetime and surface recombination velocity obtained by transverse optical probing and multi-wavelength technique 总被引:1,自引:0,他引:1
L. Sirleto A. Irace G. F. Vitale L. Zeni A. Cutolo 《Optics and Lasers in Engineering》2002,38(6):461-472
In this paper, a contactless, all-optical and non-destructive technique for simultaneous measurement of minority carrier recombination lifetime and surface recombination velocity is presented. The principle is based upon measurement, at low injection level, of the free carrier optical absorption transient probed by an infrared beam following electron–hole pairs excitation by a pulsed laser beam working at several wavelengths. Being contactless and non-destructive with respect to the surface to be analyzed, the method is appealing for routine lifetime characterization. A brief review of the theory underlying the measurement technique, aimed to emphasize its advantages and limits, and preliminary experimental data proving the applicability of the new scheme are presented. 相似文献
938.
939.
940.
Stanimirova I Michalik K Drzazga Z Trzeciak H Wentzell PD Walczak B 《Analytica chimica acta》2011,(1):1-7
The aim of this paper is to show how it is possible to extract analytical information from images acquired with a flatbed scanner and make use of this information for real time control of a nickel plating process. Digital images of plated steel sheets in a nickel bath are used to follow the process under degradation of specific additives. Dedicated software has been developed for making the obtained results accessible to process operators. This includes obtaining the RGB image, to select the red channel data exclusively, to calculate the histogram of the red channel data and to calculate the mean colour value (MCV) and the standard deviation of the red channel data. MCV is then used by the software to determine the concentration of the additives Supreme Plus Brightner (SPB) and SA-1 (for confidentiality reasons, the chemical contents cannot be further detailed) present in the bath (these two additives degrade and their concentration changes during the process). Finally, the software informs the operator when the bath is generating unsuitable quality plating and suggests the amount of SPB and SA-1 to be added in order to recover the original plating quality. 相似文献