A sensitive and accurate method/ test to predict the lifetime of aluminum oxide used as a tunnel barrier in magnetic random access memory (MRAM) has been devised. The performance of magnetic tunnel junction is dependent upon the lifetime of aluminum oxide. Aluminum oxide has also been used in high dielectric constant gate dielectric MOS devices suitable for high speed applications. This method ...

The Layer 2 Tunneling Protocol (L2TP) provides a standard method for setting up and managing L2TP sessions to tunnel a variety of L2 protocols. One of the reference models supported by L2TP describes the use of an L2TP session to connect two Layer 2 circuits attached to a pair of peering L2TP Access Concentrators (LACs), which is a basic form of Layer 2 Virtual Private Network (L2VPN). This doc...

This paper describes several flow visualization experiments carried out in Mach 3 and Mach 8 turbulent shear flows. The experimental technique was based on laser scattering from particles of H2O or CO2 condensate that form in the wind tunnel nozzle expansion process. The condensate particles vaporize extremely rapidly on entering the relatively hot fluid within a turbulent structure, so that a ...

w data, valuable contributions have been made to the physical understanding of turbulence over an unprecedented range of Reynolds numbers. The shear stress measurements were made at the unique SLTEST (Surface Layer Turbulence and Environmental Science Test facility) site on the great salt lakes of Utah, pictured in figure 1. Winds over the site are known to remain strong and consistent for exte...

Among the few classes of computational approaches for examining rarefied gas dynamics, the most widely used technique for spatial scales relevant to suborbital spaceflight is the direct simulationMonte Carlo method. One area in which the direct simulation Monte Carlo method can be improved is the numerical modeling of the interactions between gas molecules and solid surfaces. Gas–surface intera...

This article reports on the use of a shock tunnel to study the operation of scramjet powered configurations at sub-orbital velocities above 2 km/s. Thrust, as given by a net thrust equation, is used as a figure of merit throughout the study. After a short description of the shock tunnel used and its operating characteristics, experiments on the combustion release of heat in a constant area duct...

In coastal cities, some paralleled twin tunnels must be constructed in soft soil layers, and stratum reinforcement is necessary to enhance the stability of tunnel. However, influence construction following tunnel on preceding reinforced strata not clear. This study focuses four kinds strategies: ring right (RR), left (LR), (TR), cement wall between (CR). The interaction mechanism during constru...

Non-destructive test methods are often used in tunnel construction to check the required lining thicknesses. Hereby, mostly ground penetrating radar, impact-echo and ultrasonic echo are applied. However, the current knowledge and experience is largely limited to testing the concrete thickness of double-shell tunnels. Problems with the application of non-destructive test methods can arise, when ...

Volvo Car Corporation (VCC) uses Computational Fluid Dynamics (CFD) and wind tunnel during the aerodynamic development of new vehicles. In the past VCC main focus has been on the drag force correlation to the wind tunnel measurements but in recent years improved methods for lift force correlations has been highly wanted. Three objectives were considered in this study to improve the lift force c...