time-of-flight diffraction method (tofd) is an amplitude-independent sizing method which is based on the measurement of time-of-flight of defect tip diffracted waves. although tofd can measure through-wall length of defect accurately, this method is not capable of measuring horizontal defect size. in this paper, a new tofd method for evaluating horizontal planar defects is presented. the finite...

We study the territory covered by N Lévy flights by calculating the mean number of distinct sites, ^SN(n)&, visited after n time steps on a d-dimensional, d>2, lattice. The Lévy flights are initially at the origin and each has a probability Al 2(d1a) to perform an l -length jump in a randomly chosen direction at each time step. We obtain asymptotic results for different values of a . For d52 an...

the performance and flight behavior of the potato aphid macrosiphum euphorbiae was studied on the 'superior-bt' line transgenic for the cryiiia toxin of bacillus thuringien-sis (bt), resistant to the colorado potato beetle; and non transformed 'superior' line which served as control. mortality of the treated aphids was negligible and potato lines did not affect the development time of m. euphor...

A Lévy process is observed at time points of distance ∆ until time T . We construct an estimator of the Lévy-Khinchine characteristics of the process and derive optimal rates of convergence simultaneously in T and ∆. Thereby, we encompass the usual lowand high-frequency assumptions and obtain also asymptotics in the mid-frequency regime.

A long landing is one type of flight incident that will multiply the risk of a runway excursion. It occurs frequently but receives little attention in research due to difficulty in obtaining the real flight data. The aim of this paper is to discover key flight parameter features of long landing incidents by analyzing Quick Access Recorder (QAR) data and put forward prevention measures from the ...

Martin Powell makes the point that the death of the National Health Service (NHS) is constantly asserted without criteria. This article suggests that the NHS is many things, which makes criteria unstable. The alignment of interests in the structure of the NHS enables both overheated rhetoric and political strength, and that pluralization of provision might actually undermine that alignment over...

In this paper we characterize the mean and the distribution of the first exit time of a Lévy flight from a bounded region in N-dimensional spaces. We characterize tight upper and lower bounds on the tail distribution of the first exit time, and provide the exact asymptotics of the mean first exit time for a given range of step-length distribution parameters.