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Showing 1 to 18 of 18 for “"Oscillatory Behaviour"”.
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The asymptotic and oscillatory behaviour of difference and differential equations
This thesis deals with the asymptotic and oscillatory behaviour of the solutions of certain differential and difference equations. It mainly consists of three parts. The first part is to study the asymptotic behaviour of certain differential equations. The second part is to look for oscillatory …
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Computational Fluid Dynamics Investigation of Oscillatory Behaviour in Annular Combustors
… employed to counter this issue may result in oscillatory behaviour, which can cause substantial damage to the engine. Recent work has been undertaken on predicting this behaviour in annular combustors. The complexity of the annular design can give rise to an additional set of intricate …
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ΜΕΛΕΤΗ ΜΑΓΝΗΤΟΑΝΤΙΣΤΑΣΗΣ ΣΕ ΜΟΝΟΚΡΥΣΤΑΛΛΟΥΣ FE7S8
… OUTSIDE THIS RANGE, ΔΡ/Ρ(O) EXHIBITS AN OSCILLATORY BEHAVIOUR.
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Controllable, non-oscillatory damping for deformable objects
… interface, with intuitive control over the behaviour of the material. This method is particularly suited for strongly damped materials, which account for the majority of objects of interest to animation, since it produces non-oscillatory behaviour. This is similar to critical damping, except …
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Coexistence of Slow Magnetoacoustic Waves and Thermal Limit Cycles in a Coronal Bright Point
… plasma as a function of time, which exhibit oscillatory behaviour. We detect and analyse 792 oscillation events with periods ranging from 3 to 240 min. We observe spatial coherence across regions and find, with increasing periodicity, collective behaviour on a spatial scale larger than an …
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Nonlinear Dynamics of solitary and optically-injected spin vertical-cavity lasers
… Quantum-Well (QW) spin-VCSELs. Various forms of oscillatory behaviour causing self-sustained oscillations in the polarisation of the spin-VCSEL subject to Continuous-Wave (CW) pumping are found. Additionally, this work is extended to study experimentally and theoretically the evolution of the …
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Mathematical modelling of thixotropic and antithixotropic fluids
… of our investigations is on the periodic oscillatory behaviour of the systems, rather than on the transient initial phase during which the system adjusts to the attracting periodic solution. In chapter 4 we consider the two-dimensional flow of a thixotropic or antithixotropic fluid along a …
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Mathematical modelling of pulsatility in neuroendocrine systems.
… mathematical description of the characteristic oscillatory electrical behaviour of certain neurosecretory cells found in the hypothalamus of the mammalian brain. This study concentrates on those cells which secrete the hormone oxytocin. A model first described by Hodgkin and Huxley is used as a …
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High accuracy computational methods for the semiclassical Schrödinger equation
… is carried out by characterising the highly oscillatory behaviour of the solution.
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Inverse modelling and inverse simulation for system engineering and control applications
… oscillations” which leads to low-frequency oscillatory behaviour in the inverse solutions. Moreover, the need for derivative information may limit their applicability for situations involving manoeuvre discontinuities, model discontinuities or input constraints. Two new methods are developed …
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Topics in number theory
… (σ₀), that ζ(s) ≠ O for σ > σ₀. The orders and oscillatory behaviour of a variety of summatory functions are considered in this context. Particular study is made of the sums defined by [formula] And [formula] (k = 0, 1, 2 ...), incomplete sums of the form [formula] and summatory functions …
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Triadic Resonance Instability in finite-width internal gravity wave beams
… the resonant triad also modulate over time. This behaviour is shown to be a result of the finite spatial extent of the primary beam, which causes cyclic growth and decay of different triadic perturbations. As previously published literature does not consider the triadic energy exchange to be a …
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An updated model of the krill-predator dynamics of the Antarctic ecosystem
… to those from the Mori-Butterworth model is more oscillatory behaviour in the trajectories for krill and some of its main predators. This likely results from the different approach to modelling natural mortality for krill and warrants further investigation. That may in turn resolve a key mismatch …
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Novel Notch signalling dynamics within the molecular oscillator underlying vertebrate segmentation
… of pulsatile gene expression themselves exhibit oscillatory behaviour. Additionally, <i>Notch1</i> is found to be a target of Notch signalling, whereas <i>Dll1</i> is demonstrated to Wnt regulated. The differential regulation of <i>Notch1</i> and <i>Dll1</i> expression thus links the activity of …
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Finite element characterisation of photonic crystal fibres
… values of R. At some very low values of R, some oscillatory behaviour was observed in the curves obtained for the fibre losses, where further investigations were carried out. These oscillations appeared due to degeneration of the fundamental mode with the cladding modes. In most of the cases …
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Spherically-symmetric inhomogeneities in general relativity and their effects in cosmology
… in turn illustrate the interesting behaviour of a number of `horizons' in general cosmological models. We also consider the theoretical arguments presented by Melia for the `zero active mass' condition, which he claims is required by the Friedmann-Robertson-Walker spacetime. We …
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A comparative study between the cubic spline and b-spline interpolation methods in free energy calculations
… of using high-degree polynomials is the oscillatory behaviour towards the endpoints, also known as Runge's Phenomenon. Spline interpolation overcomes this obstacle by connecting the data points in a piecewise fashion. However, its complex formulation requires nested iterations in higher …
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Análisis experimental de los mecanismos de mejora termohidráulica en reactores de flujo oscilatorio
… of the thermal-hydraulic characteristics of oscillatory Flow reactors is carried out. These devices consist of a tubular equipment with a net flow in which an insert is introduced to promote mixing and, additionally, an oscillatory flow is superimposed. The inserts which have been studied are …