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M Pan J Suárez de Lezo A Medina M Romero E Hernández J Segura F Melian F Wangüemert M Landin F Benítez M Amat F Velasco A Torres 《Canadian Metallurgical Quarterly》1997,80(10):1336-1338
Two hundred twenty-eight patients with successful coronary stent implantation were randomized either to protamine administration and femoral sheath removal (group I, n = 117) or no heparin neutralization and delayed sheath removal (group II, n = 111). The hospital stay after treatment was shorter in patients receiving protamine; therefore, protamine use for neutralizing circulating heparin may be safely administered immediately after stent implantation. 相似文献
73.
The extensive application of emerging technologies is revolutionizing warehouse management. These technologies facilitate working with complex and powerful warehouse management models in which products do not have assigned fixed locations (random storage). Random storage allows the utilization of the available space to be optimized. In this context, and motivated by a real problem, this article presents a model that looks for the optimal allocation of goods in order to maximize the storage space availability within the restrictions of the warehouse. For the proposed model a construction method, a local search algorithm and different metaheuristics have been developed. The introduced algorithms can also be used for other purposes such as to assess when and how it is convenient to perform relocation of stored items to improve the current level of storage space availability. Computational tests performed on a set of randomly generated and real warehouse instances show the effectiveness of the proposed methods. 相似文献
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C. Boztug J. R. Sánchez‐Pérez F. F. Sudradjat RB Jacobson D. M. Paskiewicz M. G. Lagally R. Paiella 《Small (Weinheim an der Bergstrasse, Germany)》2013,9(4):622-630
The use of tensilely strained Ge nanomembranes as mid‐infrared optical gain media is investigated. Biaxial tensile strain in Ge has the effect of lowering the direct energy bandgap relative to the fundamental indirect one, thereby increasing the internal quantum efficiency for light emission and allowing for the formation of population inversion, until at a strain of about 1.9% Ge is even converted into a direct‐bandgap material. Gain calculations are presented showing that, already at strain levels of about 1.4% and above, Ge films can provide optical gain in the technologically important 2.1–2.5 μm spectral region, with transparency carrier densities that can be readily achieved under realistic pumping conditions. Mechanically stressed Ge nanomembranes capable of accommodating the required strain levels are developed and used to demonstrate strong strain‐enhanced photoluminescence. A detailed analysis of the high‐strain emission spectra also demonstrates that the nanomembranes can be pumped above transparency, and confirms the prediction that biaxial‐strain levels in excess of only 1.4% are required to obtain significant population inversion. 相似文献
75.
R. Bravo J.L. Pérez‐Aparicio T.A. Laursen 《International journal for numerical methods in engineering》2012,92(9):753-781
An energy frictional dissipating algorithm (EFDA) for time integration of Coulomb frictional impact‐contact problems is presented. With the use of the penalty method, and in the context of a conserving framework, linear and angular momenta are conserved, and energy is consistently dissipated. Previously published formulations were stable, forcing the energy dissipation to be monotonic to prevent unstable energy growth. The shortcoming of many was that they were not able to reproduce the real kinematics and dissipation of physical processes, provided by analytical formulations and experiments. EFDA formulates a conserving framework on the basis of a physical energy dissipation estimator. This framework uses an enhanced penalty contact model based on a spring and a dashpot, enforcing physical frictional energy dissipation, controlling gap vibrations, and modifying the velocities and contact forces during each time step. The result is that the dissipated energy, kinematics, and contact forces are consistent with the expected physical behavior. Energy frictional dissipating algorithm has been applied to four rigid‐body frictional problems using the discrete element method. The first problem is the analysis of a disk moving on a flat rough surface; the second problem analyzes the kinematics and energy dissipation of elliptical particle impacts. Numerical solutions are compared with analytical ones in both problems. The motion and impact of two disks moving on a semicircular surface are studied in the third problem. Finally, the fourth problem simulates the collapse of a two‐dimensional granular column, which is compared with the experimental results. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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Ramiro-Manzano F Fenollosa R Xifré-Pérez E Garín M Meseguer F 《Advanced materials (Deerfield Beach, Fla.)》2011,23(27):3022-3025
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Dector D. Olivares-Ramírez J. M. Ovando-Medina V. M. Sosa Dominguez A. Villa A. L. Duarte-Moller A. Sabaté N. Esquivel J. P. Dector A. 《Microsystem Technologies》2019,25(1):211-216
Microsystem Technologies - A passive micro direct glucose fuel cell (μDGFC) using SU8-current collector structures of 8 × 14 mm with a grid that allows the delivery... 相似文献
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