Communicated June 30, 1964 The problem of the diffraction of obliquely incident scalar waves by finite slits and strips with various boundary conditions has been considered previously.' Reference may be made to the work of other authors on the diffraction of scalar waves by finite slits.2 The problem of the diffraction of obliquely incident vector elastic waves by a clamped finite strip has als...

Introduction: Cracks are a key feature that determines the structural integrity of rocks, and their angular distribution can be used to determine local or regional stress patterns. The temporal growth cracks monitored in order predict impending failures materials structures such as weakened dam. Thus, spatial-temporal distributions should automatically for assessing integrity, associated patter...

iranian crack is a new form of narcotic substance that has found widespread prevalence iniran in the past years. crack only nominally resembles crack cocaine as it is widely different inits clinical signs. thus the present study aims to quantify the chemical combination of this drug.the samples included 18 specimen of crack collected from different zones of tehran, iran.all specimens were in th...

We use semi-analytical modelling of galaxy formation to predict the redshift-size-evolution of elliptical galaxies. Using a simple model in which relative sizes of elliptical galaxies of a given mass correlate with the fraction of stars formed in a star burst during a major merger event, we are able to reproduce the observed redshift-size-evolution. The size evolution is a result of the amount ...

Especially for ageing aircraft the development of fatigue cracks at fastener holes due to stress concentration and varying loading conditions constitutes a significant maintenance problem. High frequency guided waves offer a potential compromise between the capabilities of local bulk ultrasonic measurements with proven defect detection sensitivity and the large area coverage of lower frequency ...