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991.
992.
F. Ádám 《Electrical Engineering (Archiv fur Elektrotechnik)》1938,32(1):64-70
Zusammenfassung Unter Verhältnissen, wie sie praktisch bei Induktionsmaschinen vorkommen, ist für ungesättigte, unendlich dünne Zahnkopfstege und bei gegebenem LuftspaltB
min/B
max nur von dem Nutenschlitz abhängig. Für die offene Nut mit derselben Schlitzöffnung istB
min/B
max größer, der Cartersche Faktor kleiner als für die oben gekennzeichnete Nut. Der von Weber angegebene Verlauf der Induktion im Luftspalt [13] entspricht auch bei gesättigten Zahnspitzen nicht der Wirklichkeit. 相似文献
993.
994.
995.
996.
Roberto Moreno Soriano Nuria Rojas Emilio Nieto Rosa de Guadalupe González-Huerta Juan Manuel Sandoval-Pineda 《International Journal of Hydrogen Energy》2021,46(51):25944-25953
To keep optimally connected, all electrolysis cell elements is one of the most important design criteria. The optimal distribution of the clamping points is crucial to increasing cell performance. In this work, the compression pressure distribution inside of a 25 cm2 PEM electrolysis cell was evaluated, using different materials: Teflon®, Viton®, ethylene propylene diene monomer rubber (EPDM), and nitrile rubber. Sealing material evaluation was performed taking as performance indicators: total compressed area (%) and compression pressure, for different torques applied. Pressure distribution was obtained by using pressure-sensitive films, analyzing the distribution of pressure points from three-dimensional plots (3D), and quantifying intensities of the images obtained. Results showed that pressure points distribution depends on the stiffness and thickness of the gasket materials. For a tightening torque of 3.70 N m, a pressure of 2.23 MPa is obtained with 85% of the membrane area compressed using nitrile rubber-EPDM gaskets. 相似文献
997.
A. Mendizabal J. B. González-Díaz M. San Sebastián A. Echeverría 《Journal of Materials Engineering and Performance》2016,25(7):2670-2678
This paper describes the implementation of a simple strategy adopted for the inherent shrinkage method (ISM) to predict welding-induced distortion. This strategy not only makes it possible for the ISM to reach accuracy levels similar to the detailed transient analysis method (considered the most reliable technique for calculating welding distortion) but also significantly reduces the time required for these types of calculations. This strategy is based on the sequential activation of welding blocks to account for welding direction and transient movement of the heat source. As a result, a significant improvement in distortion prediction is achieved. This is demonstrated by experimentally measuring and numerically analyzing distortions in two case studies: a vane segment subassembly of an aero-engine, represented with 3D-solid elements, and a car body component, represented with 3D-shell elements. The proposed strategy proves to be a good alternative for quickly estimating the correct behaviors of large welded components and may have important practical applications in the manufacturing industry. 相似文献
998.
999.
Camilo Zúñiga Gerard Lligadas Juan Carlos Ronda Marina Galià Virginia Cádiz 《Polymer》2012,53(15):3089-3095
This work concerns the investigation of porous polybenzoxazines based on the non-toxic renewable diphenolic acid. The approach described relies on the in situ generation of foaming agent (CO2) during the thermal curing. For this purpose, the previously synthesized benzoxazine monomer from diphenolic acid was thermally polymerized at different temperatures. As the beginning of decarboxylation is about 200 °C, we selected five foaming temperatures (Tf) ranging from 190 to 230 °C. The influence of the foaming temperature on the cellular structure and its dependency on final properties is discussed. 相似文献
1000.
In this article we present Ethane, a parallel heterogeneous metaheuristic model specifically designed for its execution on heterogeneous hardware environments. With Ethane we propose a hybrid parallel search algorithm inspired in the structure of the chemical compound of the same name, implementing a heterogeneous island model based in the structure of the chemical bonds of the ethane compound. Here we also shape a schema for describing a complete family of parallel heterogeneous metaheuristics inspired by the structure of hydrocarbons in nature, HydroCM (HydroCarbon inspired Metaheuristics), establishing a resemblance between atoms and computers, and between chemical bonds and communication links. Our goal is to gracefully match computers of different computing power to algorithms of different behavior (genetic algorithm and simulated annealing in this study), all them collaborating to solve the same problem. In addition to the nice natural metaphor we will show that Ethane, though simple, can solve search problems in a faster and more robust way than well-known panmictic and distributed algorithms very popular in the literature, as well as can achieve a better exploration/exploitation balance during the search process. 相似文献