The transformation of the eikonal equation from depth coordinates (z, x) into verticaltraveltime coordinates (τ ,ξ ) enables the computation of reflections traveltimes independent of depth-mapping. This separation allows the focusing and mapping steps to be performed sequentially even in the presence of complex velocity functions, that otherwise would “require” depth migration. The traveltimes ...

This study aimed to identify the bottlenecks in patients' journeys through an emergency department (ED). For each stage of the patient journey, the average times were compared between two groups divided according to the four hour time frame and disproportionate delays were identified using a significance test These bottlenecks were evaluated with reference to a lean thinking value-stream map an...

We address the problem of how to develop and assess algorithms for tracking local focus and for proposing referents of pronouns. Previous focusing research has not adequately addressed the processing of complex sentences. We discuss issues involved in processing complex sentences and review a methodology used by other researchers to develop their focusing frameworks. We identify difficulties wi...

According to the ‘median-voter’ hypothesis, greater inequality in the market distribution of earnings or income tends to produce greater generosity in redistributive policy. We outline the steps in the causal chain specified by the hypothesis and attempt to assess these steps empirically. Prior studies focusing on crosscountry variation have found little support for the median-voter model. We e...

We study the densities of uniform random walks in the plane. A special focus is on the case of short walks with three or four steps and, less completely, those with five steps. As one of the main results, we obtain a hypergeometric representation of the density for four steps, which complements the classical elliptic representation in the case of three steps. It appears unrealistic to expect si...

every year, for realizing the goals of five-year state civil development plan, a great part of state credits and financial resources are spent for investment in national projects, whilst most of national projects are performed with considerable delay. essential objectives of applying this research is design and explanaion of national projects managers’ competencies model, focusing on risk that ...