Amplitude of jump motion signatures in classical vibration-jump dynamics

Abstract Various nuclear magnetic resonance (NMR) methods are combined to study the structure and dynamics of Li1.5Al0.5Ti1.5(PO4)3 (LATP) samples, which were obtained from sintering at various temperatures between 650 and 900 °C. 6Li, 27Al, and 31P magic angle spinning (MAS) NMR spectra show that LATP crystallites are better defined for higher calcination temperatures. Analysis of 7Li spin-lattice relaxation and line-shape changes indicates the existence of two species of lithium ions with clearly distinguishable jump dynamics, which can be attributed to crystalline and amorphous sample regions, respectively. An increase of the sintering temperature leads to higher fractions of the fast lithium species with respect to the slow one, but hardly affects the jump dynamics in either of the phases. Specifically, the fast and slow lithium ions show jumps in the nanoseconds regime near 300 and 700 K, respectively. The activation energy of the hopping motion in the LATP crystallites amounts to ca. 0.26 eV. 7Li field-gradient diffusometry reveals that the long-range ion migration is limited by the sample regions featuring slow transport. The high spatial resolution available from the high static field gradients of our setup allows the observation of the lithium ion diffusion inside the small (<100 nm) LATP crystallites, yielding a high self-diffusion coefficient of D = 2 × 10−12 m2/s at room temperature.

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Option Valuation with Observable Volatility and Jump Dynamics

SSRN Electronic Journal ◽

10.2139/ssrn.2494379 ◽

2014 ◽

Cited By ~ 1

Author(s):

Peter Christoffersen ◽

Bruno Feunou ◽

Yoontae Jeon

Keyword(s):

Option Valuation ◽

Jump Dynamics

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Free and Forced Wave Vibration Analysis of a Timoshenko Beam/Frame Carrying a Two-Degree-of-Freedom Spring-Mass System

Journal of Vibration and Acoustics ◽

10.1115/1.4050808 ◽

2021 ◽

pp. 1-25

Author(s):

Carole Mei

Keyword(s):

Timoshenko Beam ◽

Discrete Systems ◽

Degree Of Freedom ◽

Combined System ◽

Bending Vibrations ◽

Mass System ◽

Short Beam ◽

Beam Frame ◽

Classical Vibration ◽

Two Degree Of Freedom

Abstract In this paper, free and forced vibrations of a transversely vibrating Timoshenko beam/frame carrying a discrete two-degree-of-freedom spring-mass system are analyzed using the wave vibration approach, in which vibrations are described as waves that propagate along uniform structural elements and are reflected and transmitted at structural discontinuities. From the wave vibration standpoint, external excitations applied to a structure have the effect of injecting vibration waves to the structure. In the combined beam/frame and two-degree-of-freedom spring-mass system, the vibrating discrete spring-mass system injects waves into the distributed beam/frame through the spring forces at the two spring attached points. Assembling the propagation, reflection, transmission, and external force injected wave relations in the beam/frame provides an analytical solution to vibrations of the combined system. In this study, the effects of rotary inertia and shear deformation on bending vibrations are taken into account, which is important when the combined structure involves short beam element or when higher frequency modes are of interest. Numerical examples are given, with comparisons to available results based on classical vibration theories. The wave vibration approach is seen to provide a systematic and concise solution to both free and forced vibration problems in hybrid distributed and discrete systems.

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Exchange options under clustered jump dynamics

Quantitative Finance ◽

10.1080/14697688.2019.1704045 ◽

2020 ◽

Vol 20 (6) ◽

pp. 949-967 ◽

Cited By ~ 1

Author(s):

Yong Ma ◽

Dongtao Pan ◽

Tianyang Wang

Keyword(s):

Jump Dynamics ◽

Exchange Options

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Firm characteristics and jump dynamics in stock prices around earnings announcements

The North American Journal of Economics and Finance ◽

10.1016/j.najef.2019.101003 ◽

2019 ◽

Vol 50 ◽

pp. 101003

Author(s):

Haigang Zhou ◽

John Qi Zhu

Keyword(s):

Stock Prices ◽

Earnings Announcements ◽

Firm Characteristics ◽

Jump Dynamics

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Simulation and Characterization of a Nonlinear Dual-Frequency Piezoelectric Energy Harvester

Proceedings ◽

10.3390/proceedings2130908 ◽

2018 ◽

Vol 2 (13) ◽

pp. 908 ◽

Cited By ~ 2

Author(s):

Sofiane Bouhedma ◽

Yuhang Zheng ◽

Dennis Hohlfeld

Keyword(s):

Energy Harvester ◽

Frequency Tuning ◽

Dual Frequency ◽

Piezoelectric Energy ◽

Frequency Agile ◽

Classical Vibration ◽

Multi Mode

In this paper, we present a concept, simulation and characterization results of a dual-frequency piezoelectric energy harvester with magnetic frequency tuning capabilities. We demonstrate that the frequency-agile multi-mode capability enables the device to harvest on a wider range of operating frequencies than classical vibration harvesters.

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An analysis method of the vortex-induced vibrations of a tethered sphere

Meccanica ◽

10.1007/s11012-020-01231-0 ◽

2020 ◽

Vol 55 (10) ◽

pp. 1949-1974

Author(s):

Marco Negri ◽

Domenica Mirauda ◽

Stefano Malavasi

Keyword(s):

Relevant Literature ◽

Reynolds Numbers ◽

Periodic Pattern ◽

Analysis Method ◽

Phase Average ◽

Vortex Induced Vibrations ◽

Present Complex ◽

Wide Range ◽

Low Mass ◽

Classical Vibration

Abstract Vortex-induced vibrations (VIV) in systems with more than one degree of freedom often present complex synchronization among the motion components, also hidden by the randomness that characterizes the motion itself. A phase average method has been here developed and applied to the displacements of a tethered sphere, at low mass and damping, to analyze its xy trajectories over a wide range of reduced velocities, 5 ≤ U* ≤ 25 (Reynolds numbers, 5.1 × 103 ≤ Re ≤ 2.67 × 104). This method has allowed the identification of both the periodic and chaotic contribution of each motion component, accurately reconstructing the underlying trajectory periodic pattern. The two classical vibration modes, I and II, have been also observed. The method developed here was able to better rebuild the experimental data compared to other methods found in the relevant literature, providing useful insights into the study of the dynamic response of a freely-oscillating tethered sphere immersed in a steady flow.

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