Results 51 to 60 of about 161,605 (253)

Four Directions, One Solution: Enabling Rapid Diffusion Tensor MRI for Ultra‐Low Field Using Deep Learning

Magnetic Resonance in Medicine, EarlyView.
ABSTRACT Purpose This study revisits the tetrahedral encoding strategy originally proposed to accelerate Diffusion Tensor Magnetic Resonance Imaging (DT‐MRI) by reducing the requisite number of diffusion‐weighted measurements to four. We examine its practical limitations and explore how artificial intelligence (AI) can extend its utility. Specifically,
Joshua Mawuli Ametepe, James Gholam, Leandro Beltrachini, Mara Cercignani, Derek Kenton Jones   +4 more
wiley   +1 more source

MATHEMATICS OF THE FÂ: CASE OF ALGEBRA AND GEOMETRY

Universal Journal of Mathematics and Mathematical Sciences, 2021
d’ALMEIDA Zokpé Zoki, EDARH-BOSSOU Toyo Koffi   +1 more
openaire   +1 more source

Bending Analysis of Thickness‐ and Shear‐Deformable Materially Imperfect Composite Shells With von Kármán‐Type Geometric Nonlinearities

International Journal of Mechanical System Dynamics, EarlyView.
ABSTRACT Geometrically nonlinear static analysis of materially imperfect composite doubly curved shells is investigated via the generalised differential quadrature method. The effects of both shear and thickness deformation are considered through a thickness‐ and shear‐deformable third‐order theory formulated in curvilinear coordinates, while the ...
Behrouz Karami, Mergen H. Ghayesh, Shahid Hussain, Marco Amabili   +3 more
wiley   +1 more source

A Comprehensive Multistage Average Controller for Trajectory Tracking in Solar‐Powered Mobile Robots: Analysis of Actuator‐Driver and Power Stage Integration

International Journal of Mechanical System Dynamics, EarlyView.
ABSTRACT This work addresses the challenge of bidirectional trajectory tracking in solar‐powered wheeled mobile robots (WMRs), considering the mechanical structure, actuator‐driver, and power stage subsystems. Notably, this is the first study to explicitly model and control the actuator‐driver subsystem within this context. The proposed solution relies
Benjamin Natanael Santiago‐Nogales, Julio Cesar Ordaz‐Dehesa, Ramón Silva‐Ortigoza, Erik Reyes‐Reyes, J. Martín Alba‐Martínez, Juan Eduardo Velázquez‐Velázquez, José Rafael García‐Sánchez, Magdalena Marciano‐Melchor, Hind Taud   +8 more
wiley   +1 more source

Uncertainty, Sensitivity, and Efficiency Analysis of a Hybrid Piezoelectric–Electromagnetic Energy Harvester

International Journal of Mechanical System Dynamics, EarlyView.
ABSTRACT Digitalization and emerging technologies are increasing the demand for wireless sensing and the Internet of Things (IoT), which provide opportunities for autonomous sources of electricity in the form of energy harvesting systems. This paper focuses on the challenges in hybrid piezoelectric‐electromagnetic kinetic energy harvesting systems that
Petr Sosna, Damian Gaska, Zdeněk Hadaš
wiley   +1 more source

Robust Position Control of an Electro‐Hydraulic Actuator via Metaheuristic Optimization of a Fractional‐Order PID Controller

International Journal of Mechanical System Dynamics, EarlyView.
ABSTRACT In this study, a robust position control strategy is presented for a two‐stage electro‐hydraulic actuator system using a fractional‐order proportional–integral–derivative (FOPID) controller tuned by Kirchhoff's law algorithm (KLA). Electro‐hydraulic systems exhibit strong nonlinearities, parameter uncertainties, and external disturbances ...
Ridvan Firat Cinar, Davut Izci, Serdar Ekinci, Mohammad Salman, Mohammad Al‐Rabayah, Ali Akdagli, Ali Yildiz, Filiz Karaomerlioglu, Gökhan Yüksek   +8 more
wiley   +1 more source

Coexistence, crossover and extirpation in coalescent communities and ecotones

Oikos, EarlyView.
When two ecological communities come into contact, the strength of their mixing determines whether species coexist, extirpate, or extend their ranges. We present analytical formulas and simulations describing these transitions. Specifically, we derive abundance shifts upon community coalescence, identify the critical mixing strength leading to first ...
Martin Heidelman, Dervis Can Vural
wiley   +1 more source

Impact of Packaging and Recycling Systems on Material Recirculation: A Stage‐Decomposition Model

Packaging Technology and Science, EarlyView.
A system‐level view emerges from decomposing recycling into four stages (participation, collection, sorting and process yield), diagnosing constraints and targeting interventions. Cumulative equivalent uses (CEUs) quantify long‐term retention, revealing marginal improvements at high baselines generate disproportionately larger gains than low‐baseline ...
Diogo Figueirinhas, Daniel Hellström, Henrik Pålsson, Yulia Vakulenko   +3 more
wiley   +1 more source

New views of some invariants associated with the Cartesian 2D velocity gradient tensor

Quarterly Journal of the Royal Meteorological Society, EarlyView.
Vorticity and divergence of horizontal flow are fundamental quantities in meteorology; both are linear functions of the four elements of the 2D velocity gradient tensor and both are formally unchanged under coordinate rotation. We explore four quadratic functions of the elements that are geometrically invariant in this sense, finding some novel ...
I. Roulstone, S. A. Clough, A. A. White
wiley   +1 more source

Sliding Mode Control in Aerospace Applications: A Survey

International Journal of Robust and Nonlinear Control, EarlyView.
ABSTRACT Sliding mode control (SMC) enjoys robustness to matched and unmatched (in the case of minimum phase input‐output dynamics) bounded perturbations, and finite time convergence. Second‐order and higher‐order sliding mode control systems (2‐SMC/HOSMC) retain all the advantages of sliding mode control, but in addition can be applied to systems of ...
Yuri Shtessel, Christopher Edwards
wiley   +1 more source