Results 1 to 10 of about 616,376 (202)
Applied Sciences, 2021 In downhole drilling systems, self-excited torsional vibrations caused by the bit-rock interactions can affect the drilling process and lead to the premature failure of components.
Vincent Kulke +3 more
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Voices, 2022 In August 2020, two colleagues and I began an ongoing conversation on music, consent, power, language/jargon, accessibility, and inclusivity. We are not music therapists, but each of us, from our own professional and personal perspectives, is interested ...
Heather Strohschein +2 more
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A Novel Mesoscopic Drill Bit Model for Deep Drilling Applications
Modelling, 2023 This paper deals with the development of a novel mesoscopic model of polycrystalline diamond compact (PDC) drill bits that can be implemented in complex drill string models for simulations to analyse the influence of rock inhomogeneities or the impact of
Mohamed Ichaoui +2 more
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Friction, 2022 The load-bearing behaviour of lubricated contacts depends primarily on the normal force, the relative velocity, and the geometry. Thus, with the aid of the Stribeck curve, it is usually well possible to characterize whether hydrodynamics, mixed friction,
Lukas Stahl +2 more
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Sensors, 2021 Strain measurements using fibre Bragg grating (FBG) optical sensors are becoming ever more commonplace. However, in some cases, these measurements can become corrupted by sudden jumps in the signal, which manifest as spikes or step-like offsets in the ...
Dominik Johannes Marius Fallais +4 more
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Journal of Physics A: Mathematical and General, 2000 Summary: The effect of a high-frequency force on the response of a bistable system to a low-frequency signal is considered for both the overdamped and weakly damped cases. It is shown that the response can be optimized by an appropriate choice of vibration amplitude.
Landa, P. S., McClintock, Peter V. E.
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Shock and Vibration, 2021 In this paper, a passive damper based on energy dissipation through shock and dry friction (shock-friction damper) is investigated regarding its design and effectiveness for damping self-excited torsional vibrations similar to those occurring in deep ...
Vincent Kulke +2 more
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Aerodynamic Characteristics of a Z-Shaped Folding Wing
Aerospace, 2023 Z-shaped folding wings have the potential to enhance the flight performance of an aircraft, contingent upon its mission requirements. However, the current scope of research on unmanned aerial vehicles (UAVs) with Z-shaped folding wings primarily focuses ...
Yongchang Huang +2 more
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Exploring Fatigue Effects on Performance Variation of Intensive Brain–Computer Interface Practice
Frontiers in Neuroscience, 2021 Motor imagery (MI) is an endogenous mental process and is commonly used as an electroencephalogram (EEG)-based brain–computer interface (BCI) strategy. Previous studies of P300 and MI-based (without online feedback) BCI have shown that mental states like
Songwei Li +5 more
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Stability and bifurcation analyses for exterior resonant families in Earth-Moon system
Results in Physics, 2021 In this work, stability and bifurcation analyses for exterior resonant orbit families have been investigated for a test spacecraft around Earth-Moon system. The initial states are obtained for certain resonance ratio orbits in the two-body problem.
Xu Li +3 more
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