A simple relation between the root mean square (rms) of the ground acceleration and earthquake spectral (or source) parameters is introduced: EQ-TARGET;temp:intralink-;;55;590 Arms ! "2π#Ω0 f0 !!!!!!!!! πκT p "1$ πκf0 1:50:25# 2 ; in which Ω0 is the low-frequency displacement spectral plateau, f0 is the corner frequency, κ is an attenuation parameter, and T is the data interval. This result use...

The present paper deals with the analysis and development of noise-reduction transformer that has a filter function for conductive noise transmission. Two types of prototype noise-reduction transformers with two different output voltages are proposed. To determine an optimum design for the noise-reduction transformer, noise attenuation characteristics are discussed based on the experiments and ...

Stress waves contain useful information about the properties of porous materials; they can be recovered through different non-destructive testing methods such as crosswell, vertical seismic profile, borehole logging as well as sonic tests. In all these methods, it is crucial to assess the effects of frequency on wave attributes including velocity and intrinsic attenuation. The dependency of per...

An analytical overview of research involving EM waves attenuation by vegetation canopies in the frequency range 100...10000 MHz is given. Brief descriptions of objects of investigation and typical biometric features are presented. The models of vegetation as a continuous medium and as a collection of scatterers are considered. Dielectric properties of vegetative material are discussed. The rela...

The velocity and attenuation of ultrasonic stress waves in gabbroic rock samples (San Marcos, California) subjected to shock loading in the 2 GPa range were studied. From P wave velocity measurements we determined the damage parameter Dp and crack density e of the samples and related these to the attenuation coefficient (quality factor) under dynamic strains of 2 x 10 -? and at a frequency of 2...

To solve noises affecting the performance of laser communication system problems, this paper studies mathematical model in atmospheric attenuation condition, sets up atmospheric attenuation coefficient of the primary factor aerosol (haze) according to the absorbing and scattering characteristics of the atmosphere, gives output SNR(Signal to Noise Ratio) models under atmosphere attenuation based...

elastic energy of seismic wave is lost through propagation into the earth. various factors affect seismic energy. some of them are frequency independent and recovered in processing steps. but other factors such as intrinsic absorption of medium are frequency dependent and cannot be recovered by processing methods. lost energy caused by these factors is called attenuation. there are various meth...

The relation between the NMR spin-echo attenuation in the magnetic field gradient and the velocity autocorrelations of molecular random migration has been derived by using the commulant expansion theorem for averaging stochastic processes. It may explain certain cases of time dependent diffusion observed in many systems. In the limit of long correlation times it is identical to Torrey’s well-kn...

  The sporozoites of Theileria annulata invade bovine MHC II cells, where they differentiate into schizonts. The later can immortalize and induce fundamental changes in their host cells. Live attenuated vaccine is an important way of controlling T. annulata infection of cattle. Production is by prolonged cultivation of macroschizont-infected cells. The mechanisms underlying this transformation ...