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991.
The aim of this letter is to derive the spectral density of decimated processes, and to establish their model when they are generated from ARMA processes. The optimal conditions of decimation are also discussed.<> 相似文献
992.
T. A. G. Langrish 《Drying Technology》2002,20(9):1789-1802
Progress in modelling air flow patterns in timber kilns using Computational Fluid Dynamics is reviewed in this work. These simulations are intended to predict the distribution of the flow in the fillet spaces between boards in a hydraulic model of a timber kiln. Here, the flow regime between the boards is transitional between laminar and turbulent flow, with Reynolds numbers of the order of 5000. Running the simulation as a transient calculation has shown few problems with convergence issues, reaching a mass residual of 0.2% of the total inflow after 40-100 iterations per time step for time steps of 0.01 s. Grid sensitivity studies have shown that non-uniform grids are necessary because of the sudden changes in flow cross section, and the flow simulations are insensitive to grid refinement for non-uniform grids with more than 300,000 cells. The best agreement between the experimentally-measured flow distributions between fillet spaces and those predicted by the simulation have been achieved for (effective) bulk viscosities between the laminar viscosity for water and ten times that value. This change in viscosity is not very large (less than an order of magnitude), given that effective turbulent viscosities are typically several orders of magnitude greater than laminar ones. This result is consistent with the transitional flows here. 相似文献
993.
P. G. Bannov G. E. Shumilova N. A. Voronina O. V. Yurkina T. F. Alekseenko 《Chemistry and Technology of Fuels and Oils》1992,28(3):178-179
Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 3, pp. 34–35, March, 1992. 相似文献
994.
995.
996.
997.
G. A. Isaak'yan V. Ya. Alekseev A. I. Ivanov N. I. Karmalitsyn A. E. Kochin T. E. Sazonova S. V. Sepman I. F. Uchevatkin V. I. Fominykh 《Atomic Energy》1992,73(5):903-907
Mendeleev All-Union Metrology Research Institute. Translated from Atomnaya Énergiya, Vol. 73, No. 5, pp. 393–397, November 1992. 相似文献
998.
I. R. Tatur D. A. Yakovlev I. A. Timokhin L. R. Berezovskii G. B. Prigul'skii V. A. Lazarev V. N. Sergeev 《Chemical and Petroleum Engineering》1992,28(10):623-627
Translated from Khimicheskoe i Neftyanoe Mashinostroenie, No. 10, pp. 29–31, October, 1992. 相似文献
999.
1000.
Measurement of human red blood cell deformability using a single micropore on a thin Si3N4 film 总被引:1,自引:0,他引:1
The filtration method for the evaluation of the RBC deformability has been further refined to simulate the deformations encountered in the recticuloendothelial system (in particular the spleen), a recognized site of aged and sickled cells removal. The core of the developed measuring system is a very thin (0.4 micron thick) filter that consists of single micropore (diameters down to 1 micron) on a Si3N4 film which has been constructed using silicon microfabrication techniques. Individual RBC's deformability is quantified measuring the cell pore passage time. From one blood sample 200 passage times are analyzed by a computer, displaying mean and median values as deformability indexes, and class and cumulative histograms for studying the passage times distribution. In this paper the effectiveness of the developed system as a routine clinical evaluation tool is demonstrated by studying several factors that are known to affect the RBC deformability, such as temperature, addition of diamide and glutaraldehyde, and blood storage conditions. In addition, it is experimentally demonstrated that the human RBC can traverse a pore with a diameter as small as 1 micron when the pore length is very short, thus broadening the experimental conditions under which the RBC deformability (fluidity) can be studied. 相似文献