Coupling multistable systems : uncertainty due to the initial positions on the attractors

Acknowledgment This work has been supported by the Foundation for Polish Science, Team Programme – Project No. TEAM/2010/5/5.Peer reviewedPublisher PD

Coupling multistable systems: uncertainly due to the initial positions on the attractors.

We consider the coupling of multistable nonidentical systems. For small values of the coupling coefficient the behavior of the coupled system strongly depends on the actual position of trajectories on their attractors in the moment when the coupling is introduced. After reaching the coupling threshold value, this dependence disappears. We give an evidence that this behavior is robust as it exists for a wide range of parameters and different types of coupling. We argue why this behavior cannot be considered as a dependence on the initial conditions

Helical buckling of thin rods : FE modelling

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Suppression of drill-string stick–slip vibration by sliding mode control : Numerical and experimental studies

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State Dependent Delayed Drill-string Vibration : Theory, Experiments and New Model

L.J. Pei would like to acknowledge NNSF of China (No. 11372282) and China Scholarship Council.Peer reviewedPublisher PD

Bifurcation scenarios in helical buckling of slender rods using new FE

The authors would like to acknowledge the use of the Maxwell High Performance Computing Cluster of the University of Aberdeen IT Service and various industrial projects sponsored by Oil & Gas Innovation Centre (OGIC), which stipulated these studies.Peer reviewedPostprin

Numerical Study on the Elastic Deformation and the Stress Field of Brittle Rocks under Harmonic Dynamic Load

Funding: The support of National Natural Science Foundation of China (No. 51704074) and Youth Science Foundation of Heilongjiang Province (No. QC2018049) are gratefully acknowledged. The work is also supported by Talent Cultivation Foundation (No. SCXHB201703; No. ts26180119; No. td26180141) and Youth Science Foundation (No. 2019QNL-07) of Northeast Petroleum University.Peer reviewedPublisher PD

Complex dynamics of drill-strings : Theory and experiments

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Experimental studies of forward and backward whirls of drill-string

The authors wish to thank BG Group plc for the financial support to this research.Peer reviewedPostprin

Application of Resonance Enhanced Drilling to coring

The authors would like to acknowledge the support of Oil & Gas Innovation Centre (OGIC), the project manager Ms Mhairi Begg, and Volcanic Basin Petroleum Research AS (VBPR). Siqi Li would like to acknowledge the support of National Natural Science Foundation of China (No. 51704074) and Youth Science Foundation of Heilongjiang Province (No. QC2018049) and Talent Cultivation Foundation (No. SCXHB201703; No. ts26180119; No. td26180141) and Youth Science Foundation (No. 2019QNL-07) of Northeast Petroleum University. The authors also would like to acknowledge the generous donation of coring drill-bits from Halliburton and Jan-Erik Rosberg for use in the project, and the preliminary work by graduate student Diana Xiuhnelli Herrera Solis.Peer reviewedPostprin