G , ~ H ~ +G,H, +CG,H, i=l Abstract This paper presents a proposed model in an explicit form and its simulation results for characterizing wideband line-of-sight (LOS) radio channel in an urban microcellular environment. The model is fast to compute, easy to implement, and only those rays that reach the receiver locations are calculated. Effect of street-grid, with any number of crossing street...

The present work reports a discrete stress-dependent, complex compliance spectra method that may be used to predict the mechanical response of nonlinear viscoelastic polymers during creep and recovery processes. The method is based on the observation that the real and imaginary parts of a discrete complex compliance frequency spectra obtained from creep and recovery measurements are smooth, eas...

An assessment of spectrum efficiency for a microcellular land mobile radio system is presented by considering the desired signal as (fast) Rician fading with (slow) lognormal shadowing and co-channel interfering signals as uncorrelated (fast) Rayleigh fading superimposed over (slow) lognormal shadowing. Spectrum efficiency is defined in terms of reuse distance, Le., cluster size, traffic intens...

Foam injection is becoming a standard conditioning agent when tunnelling with an earth-pressure balanced shield, resulting in an increasing interest in this technique. The technique is mostly based on empirical rules and experience. To be able to determine what foam and how may foam has to be injected for different soils, it is necessary to know the mechanical parameters of the foam-water-soil ...

A four-sector cross-shaped urban microcellular system with intelligent switched-beam antennas is proposed. Each sector covers a street block with a base station located at an intersection, and an intelligent beam-switching scheme is used to locate mobile users in the most suitable beam coverage. Due to directional narrow-beam patterns and waveguide effects of tall buildings, radio signals along...

With the rapid evolvement of wireless communication technologies, ever increasing needs to prevent electromagnetic waves (EMWs) pollution have urged development lightweight materials with excellent interference (EMI) shielding property. However, achieving desired EMI performance often requires high loadings conductive nanofillers, like graphene, which poses challenges control nanoparticle dispe...

Application of foam in EOR, increases macroscopic sweep efficiency via awesome increscent of mobility control. Macroscopic manifestation of foam application performance in porous media is complex process that involves several interacting microscopic foam events. Stability as an important factor in foam injection within large reservoirs, depends on several variables including oil saturation, con...

aluminum foams are a novel branch of advanced materials with superior properties. sandwich structures with aluminum foam core are good energy absorbers. in this paper, mechanical properties and energy absorption of aluminum foam sandwich panels subjected to quasi-static perforation tests with conical-nosed indenter were investigated experimentally. for this purpose sandwich panels consisting of...