the stolt (f-k) migration algorithm is a direct (i.e. non-recursive) fourier-domain technique based on a change of variables (or equivalently, a mapping) that converts the input spectrum to the output spectrum. the algorithm is simple and efficient but limited to constant velocity. a v(z)(f-k) migration method, capable of very high accuracy for vertical variations of velocity, can be formulated...

Frequency response diagrams of a system include detailed and recognizable information about the structural and parameter effects of the transfer function model of the system. The information are qualitatively and quantitatively obtainable from simultaneous consideration of amplitude ratio and phase information. In this paper, some rules and relationships are presented for making use of frequenc...

The cerebrated Kalman-Yakubovic̆-Popov (KYP) lemma establishes the equivalence between a frequency domain inequality (FDI) and a linear matrix inequality (LMI), and has played one of the most fundamental roles in systems and control theory. This paper generalizes the KYP lemma in two aspects — the frequency range and the class of systems — and unifies various existing versions by a single theore...

Domain Axel Simon Andy King Jacob M. Howe Computing Laboratory, Department of Computing, University of Kent, Canterbury, UK. City University, London, UK. {a.m.king, a.simon}@ukc.ac.uk [email protected] Abstract. This paper explores the spatial domain of sets of inequalities where each inequality contains at most two variables – a domain that is richer than intervals and more tractable than g...

Most of the researches in the domain of fuzzy number comparisons serve the fuzzy number ordering purpose. For making a comparison between two fuzzy numbers, beyond the determination of their order, it is needed to derive the magnitude of their order. In line with this idea, the concept of inequality is no longer crisp however it becomes fuzzy in the sense of representing partial belonging or de...

Purpose: The aim of this study was to characterize prolonged standing and its effect on postural control in elderly individuals in comparison to adults.Materials and Methods: The elderly individuals’ behavior during standing and how demanding such a task is for them, is still unknown. We recorded the center of pressure (COP) position of 12 elder and 15 young participants while they were standin...