Results 151 to 160 of about 14,134,355 (324)

Symmetry Analysis of the Two-Dimensional Stationary Gas Dynamics Equations in Lagrangian Coordinates

Mathematics
This article analyzes the symmetry of two-dimensional stationary gas dynamics equations in Lagrangian coordinates, including the search for equivalence transformations, the group classification of equations, the derivation of group foliations, and the ...
Sergey V. Meleshko, Evgeniy I. Kaptsov
doaj   +1 more source

Next Generation 7 Tesla Arterial Spin Labeling With Rotated Spiral Acquisition Enables Mesoscale Resolution in 3D Brain Perfusion and Functional MRI

Magnetic Resonance in Medicine, EarlyView.
ABSTRACT Purpose To achieve high resolution (≤ 1 mm isotropic) whole‐brain perfusion imaging at 7 T with next generation ASL pulse sequence, reconstruction algorithm, and MRI hardware. Methods We capitalized on three major innovations: (1) FLASH‐based pseudo‐Continuous ASL (pCASL) sequence with rotated golden‐angle stack‐of‐spirals (rGA‐SoS) sampling; (
Chenyang Zhao, Fanhua Guo, Zidong Yang, Xingfeng Shao, Samantha J. Ma, Alexander J. S. Beckett, An T. Vu, David A. Feinberg, Danny J. J. Wang   +8 more
wiley   +1 more source

Effect of Variations in the Ring Thickness on the Dynamic Performance of the Bimetal Gears

International Journal of Mechanical System Dynamics, EarlyView.
ABSTRACT This study used a six‐degrees‐of‐freedom dynamic model to analyze the dynamic response of bimetal spur gears. Aluminum alloy forms the core of the bimetal gears, and a uniform‐thickness steel ring surrounds the teeth. Gear mesh stiffness of bimetal gears and the transmission error have been assessed using a numerical approach based on finite ...
Bikramjit Singh, Pawan Kumar, S. P. Harsha   +2 more
wiley   +1 more source

Dynamics Modeling of Robot Manipulators Based on Deep Lagrangian Network and Torque Separation Technique

International Journal of Mechanical System Dynamics, EarlyView.
ABSTRACT In recent years, learning robot manipulator dynamics with deep networks has been extensively studied, as it avoids deriving the analytical expression of the robot dynamics equations. In particular, deep Lagrangian networks that incorporate the prior knowledge of Lagrangian mechanics into the deep networks have shown prominent advantages in ...
Xianglong Liang, Tianyu Gao, Zhikai Yao, Jianyong Yao   +3 more
wiley   +1 more source

Single Smooth Waveform Command‐Shaping Control of Overhead Crane Systems Utilizing Two‐Stage Acceleration–Deceleration Profile for Short‐Moving Point‐to‐Point Maneuver

International Journal of Mechanical System Dynamics, EarlyView.
ABSTRACT Modern industrial demand for efficient material handling in confined spaces has driven the need for overhead cranes capable of short‐distance point‐to‐point maneuvers without compromising payload stability. Conventional three‐stage shaper profiles, experiencing acceleration, cruising, and deceleration, become inefficient or infeasible for ...
Mohammed Alfares, Jasem Baroon, Khaled Alhazza   +2 more
wiley   +1 more source

Large Deformation Pile‐soil Interaction Under Lateral Vehicle Impact Using Hybrid SPH+FEM and EFG+FEM Models

International Journal for Numerical and Analytical Methods in Geomechanics, EarlyView.
ABSTRACT This study presents large deformation computational methods to simulate lateral vehicular impacts on steel piles in granular soil. Soil‐mounted longitudinal barrier systems rely on energy dissipation in both the piles and the surrounding soil to safely redirect errant vehicles, so dynamic pile‐soil interaction is important for design ...
Tewodros Y. Yosef, Chen Fang, Seunghee Kim, Ronald K. Faller, Qusai A. Alomari, Mojtaba Atash Bahar, Gnyarienn S. Kumar   +6 more
wiley   +1 more source

Explicit‐Implicit Material Point Method for Dense Granular Flows With a Novel Regularized µ(I) Model

International Journal for Numerical and Analytical Methods in Geomechanics, EarlyView.
ABSTRACT The material point method (MPM) is widely employed to simulate granular flows. Although explicit time integration is favored in most current MPM implementations for its simplicity, it cannot rigorously incorporate the incompressible µ(I)‐rheology, an efficient model ubiquitously adopted in other particle‐based numerical methods. While operator‐
Hang Feng, Zhen‐Yu Yin
wiley   +1 more source

An Exact Method for Reliable Shortest Path Problems With Correlation

Networks, EarlyView.
ABSTRACT Shortest path problems often arise in contexts where travel times are uncertain. In these settings, reliable paths are often valued more than paths with lower expected travel times. This has led to several variants of reliable shortest path problems (RSPP) that handle travel time reliability differently. We propose an algorithmic framework for
Esteban Leiva, Santiago Morales, Daniel Yamín, Andrés L. Medaglia   +3 more
wiley   +1 more source

Applying Dynamics/Cost Parameter Continuation to the Optimal Guidance of Variable‐Speed Unicycle

Optimal Control Applications and Methods, EarlyView.
(a) Classical parameter continuation method diverges. (b) Dynamics/cost parameter continuation method converges. ABSTRACT The problem of a variable‐speed unicycle guidance to the stationary target is considered. The vehicle should be guided to the origin while minimizing the energy loss due to the induced drag.
Gleb Merkulov, Vladimir Turetsky, Tal Shima   +2 more
wiley   +1 more source

Numerical Simulations of Very Low Velocity Impacts and Ignition of an Explosive Confined by a Thin Case

Propellants, Explosives, Pyrotechnics, EarlyView.
A low‐speed impact (around one meter per second) of a metallic tip on an explosive confined by a thin plate is simulated. The heat due to friction between the tip and the plate and the one due to the deformation of the plate are not transfered to the ignited zone.
Lucas Bonneau, Didier Picart
wiley   +1 more source