Results 51 to 60 of about 1,689,762 (301)

Lumbo-sacral Junction Instability by Traumatic Sacral Fractures: Isler’s Classification Revisited – A Narrative Review

Global Spine Journal, 2022
Study Design Narrative review Objectives Multiple classifications have been proposed for sacral fractures since the last century. While initial classifications focussed on vertical and transverse fractures, the recent fracture classifications encompass ...
Rishi M Kanna MS, MRCS, FNB, Shanmuganathan Rajasekaran PhD, Gregory D Schroeder MD, Klaus Schnake MD, Alexander R Vaccaro MD, PhD, MBA, Lorin Benneker MD, Cumhur F Oner MD, PhD, Frank Kandziora MD, PhD, Emiliano Vialle MD   +8 more
doaj   +1 more source

Observer‐Based Adaptive Event‐Triggered Tracking Control for Fuzzy TS Systems With Premise Mismatch

International Journal of Adaptive Control and Signal Processing, EarlyView.
This paper presents an adaptive logistic event‐triggered observer‐based tracking controller for Takagi‐Sugeno fuzzy systems under constrained inputs and network delays. Leveraging a hybrid LMI and Secretary Bird Optimization approach, this strategy significantly minimizes communication overhead and computational burden while ensuring optimal reference ...
Oussama Djadane, Salama Makni, Mourad Kchaou, Ahmed El Hajjaji   +3 more
wiley   +1 more source

Vertical shear instability in accretion discs [PDF]

Monthly Notices of the Royal Astronomical Society, 1993
Two-dimensional shear flows in the (R-z) and (φ-z) planes in thin accretion discs are studied. The vertical shear is set up by the resonant response of a disc with small tilt. It is shown that the flow is dynamically unstable, with growth rates in excess of ∼ 0.1 Ω −1 , corresponding to a growth time-scale of one orbital period at a given radius ...
S. Kumar, C. S. Coleman
openaire   +1 more source

Thermodynamic Pathways of Nonequilibrium Solidification in Wire‐Arc Additive Manufacturing Fe‐Based Multicomponent Alloy Structures

Advanced Engineering Materials, EarlyView.
Geometry‐driven thermal behavior in wire‐arc additive manufacturing (WAAM) influences microstructural evolution during nonequilibrium solidification of a chemically complex Fe–Cr–Nb–W–Mo–C nanocomposite system. By comparing different deposits configurations, distinct entropy–cooling rate correlations, segregation, and carbide evolution are revealed ...
Blanca Palacios, Anthony Gonzalez, Aleksander Aleman, Tyler Dolmetsch, Tanaji Paul, Arvind Agarwal   +5 more
wiley   +1 more source

On the delicate state of instability of a vertical riser transporting fluid [PDF]

, 2020
The variation in the dynamic characteristics of a flexible riser as the riser transitions from a vertical riser to a catenary-type riser is investigated.
O’Reilly, Oliver M, Kim, Hyung-Taek
core   +1 more source

Inverse Identification of Energy‐Dependent Laser Absorptivity in NiTi Laser Powder‐Bed Fusion via Calibrated Melt Pool Simulation

Advanced Engineering Materials, EarlyView.
A combined experimental–computational framework identifies energy‐dependent laser absorptivity for NiTi in laser powder‐bed fusion, applicable to conduction and transition modes. Single‐track experiments and thermofluid smoothed particle hydrodynamics simulations are coupled through inverse analysis of melt pool geometry.
Mohamadreza Afrasiabi, Hadi Moutablaleh, Ignatius A. Setiawan, Mehrshad Mehrpouya   +3 more
wiley   +1 more source

Stratified and Vertically Shearing Streaming Instabilities in Protoplanetary Disks [PDF]

The Astrophysical Journal, 2021
Abstract Under the right conditions, the streaming instability between imperfectly coupled dust and gas is a powerful mechanism for planetesimal formation as it can concentrate dust grains to the point of gravitational collapse. In its simplest form, the streaming instability can be captured by analyzing the linear stability of ...
openaire   +2 more sources

Controlling the vertical mode coupling instability with feedback in the ALS [PDF]

, 1997
The authors present the results of experiments to control the mode coupling instability in the vertical direction using a feedback system. Presently, they can raise the instability threshold from {approximately} 20 mA to 35 mA.
Barry, W., Byrd, J, Barry, W, Byrd, J.
core   +1 more source

Influence of Scan Strategies in Electron Beam Powder Bed Fusion on Solidification, Microstructure, and High‐Temperature Compressive Properties of γ′‐Strengthened Inconel 738LC

Advanced Engineering Materials, EarlyView.
Experiments and thermophysical simulations were conducted to investigate the electron beam powder bed fusion electron beam (PBF‐EB/M) process for the γ′‐strengthened nickel‐based superalloy Inconel 738LC. The results demonstrate the impact of process‐induced microstructural variations on high‐temperature mechanical behavior, providing a basis for ...
Jan Niklas Petenati, Karthik Kumar Banku, Prasanth Bondi, Ivan Zhirnov, Yangyiwei Yang, Gordon Schmidt, Jürgen Christen, Georg Hasemann, Manja Krüger, Bai‐Xiang Xu, Bilal Gökce, Silja‐Katharina Rittinghaus   +11 more
wiley   +1 more source

Vertical scale selection in inertial instability [PDF]

Journal of Fluid Mechanics, 2007
The linear instability of a barotropic flow with uniform horizontal shear in a stratified rotating fluid is investigated with respect to perturbations invariant in the alongflow direction. The flow can be inertially unstable if there is sufficiently strong anticyclonic shear, but only for sufficiently high Reynolds numbers Re. We determine the critical
Kloosterziel, R. C., Carnevale, G. F.
openaire   +1 more source