Identification and PID tuning techniques for stable and unstable SOPDT processes
Sign Up to like & getrecommendations! Published in 2018 at "International Journal of Dynamics and Control"
DOI: 10.1007/s40435-017-0362-2
Abstract: In this paper, identification and control of a process whose dynamics can be described by a second-order-plus-dead-time (SOPDT) stable/unstable model is presented. Using the state-space approach and limit cycle information, analytical expressions are derived to… read more here.
Keywords: pid tuning; tuning techniques; stable unstable; identification ... See more keywords
Stable and unstable supersonic stagnation of an axisymmetric rotating magnetized plasma
Sign Up to like & getrecommendations! Published in 2022 at "Journal of Fluid Mechanics"
DOI: 10.1017/jfm.2022.77
Abstract: Abstract The Naval Research Laboratory ‘Mag Noh problem’, described in this paper, is a self-similar magnetized implosion flow, which contains a fast magnetohydrodynamic (MHD) outward propagating shock of constant velocity. We generalize the classic Noh… read more here.
Keywords: unstable supersonic; axisymmetric rotating; supersonic stagnation; problem ... See more keywords
Thermals from finite sources in stable and unstable environments
Sign Up to like & getrecommendations! Published in 2023 at "Journal of Fluid Mechanics"
DOI: 10.1017/jfm.2023.245
Abstract: Abstract The rise of thermals in the atmosphere has attracted a lot of attention since the early work of Morton et al. (Proc. R. Soc. Lond. A, vol. 234, 1956, pp. 1–23), who proposed that… read more here.
Keywords: sources stable; analytical solutions; stable unstable; momentum ... See more keywords
A shift from drought to extreme rainfall drives a stable landslide to catastrophic failure
Sign Up to like & getrecommendations! Published in 2019 at "Scientific Reports"
DOI: 10.1038/s41598-018-38300-0
Abstract: The addition of water on or below the earth’s surface generates changes in stress that can trigger both stable and unstable sliding of landslides and faults. While these sliding behaviours are well-described by commonly used… read more here.
Keywords: shift drought; stable unstable; catastrophic failure; rainfall ... See more keywords
Understanding stable/unstable miscible A+B→C reaction front and mixing in porous medium
Sign Up to like & getrecommendations! Published in 2023 at "Physics of Fluids"
DOI: 10.1063/5.0143853
Abstract: The transport phenomena of [Formula: see text] type reactive miscible front undergoing radial displacement in a porous medium are numerically investigated. For a stable displacement when the viscosity of fluids A, B, and C is… read more here.
Keywords: formula see; reaction; instability; stable unstable ... See more keywords
Carbonates and intermediate-depth seismicity: Stable and unstable shear in altered subducting plates and overlying mantle
Sign Up to like & getrecommendations! Published in 2023 at "Proceedings of the National Academy of Sciences of the United States of America"
DOI: 10.1073/pnas.2219076120
Abstract: Significance Earthquakes at subduction zones extend to great depths where slip on faults cannot occur by conventional frictional processes. Earthquakes at depths greater than 15 km are commonly attributed to high pore pressures, low effective… read more here.
Keywords: depth seismicity; seismicity stable; stable unstable; carbonates intermediate ... See more keywords
The Stable and Unstable Oscillations of a Rod Attached to Many Springs
Sign Up to like & getrecommendations! Published in 2023 at "European Journal of Physics"
DOI: 10.1088/1361-6404/acdb0f
Abstract: The oscillation equations of a multi-spring system connected to a rod are developed. Oscillations can be stable or unstable depending on the distribution of the spring constant and the number of springs. The symmetrical spring… read more here.
Keywords: unstable oscillations; attached many; stable unstable; rod attached ... See more keywords
Linear response theory for diffeomorphisms with tangencies of stable and unstable manifolds—a contribution to the Gallavotti–Cohen chaotic hypothesis
Sign Up to like & getrecommendations! Published in 2018 at "Nonlinearity"
DOI: 10.1088/1361-6544/aae740
Abstract: This note presents a non-rigorous study of the linear response for an SRB (or `natural physical') measure $\rho$ of a diffeomorphism $f$ in the presence of tangencies of the stable and unstable manifolds of $\rho$.… read more here.
Keywords: response theory; linear response; unstable manifolds; stable unstable ... See more keywords
Stable and unstable vortex knots in excitable media.
Sign Up to like & getrecommendations! Published in 2019 at "Physical review. E"
DOI: 10.1103/physreve.99.012211
Abstract: We study the dynamics of knotted vortices in a bulk excitable medium using the FitzHugh-Nagumo model. From a systematic survey of all knots of at most eight crossings we establish that the generic behavior is… read more here.
Keywords: unstable vortex; geometry; stable unstable; excitable media ... See more keywords
When Is a Helix Stable?
Sign Up to like & getrecommendations! Published in 2020 at "Physical review letters"
DOI: 10.1103/physrevlett.125.088001
Abstract: We determine which helical equilibria of an isotropic Kirchhoff elastic rod with clamped ends are stable and which are unstable. Although the set of all helical equilibria is parametrized by four variables, with an additional… read more here.
Keywords: helix stable; stable unstable;
Learned Lifted Linearization Applied to Unstable Dynamic Systems Enabled by Koopman Direct Encoding
Sign Up to like & getrecommendations! Published in 2022 at "IEEE Control Systems Letters"
DOI: 10.1109/lcsys.2022.3231641
Abstract: This letter presents a Koopman lifting linearization method that is applicable to nonlinear dynamical systems having both stable and unstable regions. It is known that Dynamic Mode Decomposition (DMD) and its extended methods are often… read more here.
Keywords: lifted linearization; linearization applied; direct encoding; stable unstable ... See more keywords