The strong variability of magnetic central engines of AGN and GRBs may result in highly intermittent strongly magnetized relativistic outflows. We find a new magnetic acceleration mechanism for such impulsive flows that can be much more effective than the acceleration of steady-state flows. This impulsive acceleration results in kineticenergy-dominated flows that are conducive to efficient diss...

Received 17 June 2021Accepted 8 July 2021DOI:https://doi.org/10.1103/PhysRevAccelBeams.24.078002Published by the American Physical Society under terms of Creative Commons Attribution 4.0 International license. Further distribution this work must maintain attribution to author(s) and published article’s title, journal citation, DOI.Published SocietyPhysics Subject Headings (PhySH)Research AreasB...

Inviscid computations are presented of a self-propelled virtual body connected to combined heaving and pitching foil that uses continuous intermittent motions. It is determined swimming can improve efficiency when the dimensionless heave ratio $h^* < 0.7$ while it degrades for \geq 0.7$. This consequence physical origins force production pitch-dominated ($h^* 0.5$) heave-dominated > Based on in...

Current research on eco-driving has focused solving an optimal control problem (OCP) to generate a speed profile be tracked by drivers. The optimization variables are often chosen as low level actions such engine torque and gear positions, which leads complex mixed-integer problems. In this brief, we propose assistance system (EDAS) improve current EDAS in two aspects. First, adviser with simpl...

The objective of this paper is to formulate and analyze the benefits a predictive non-linear multi optimization method for platoon mild-hybrid line haul trucks. In study group three trucks with hybrid electric powertrain are considered in formation where each truck has optimal control save fuel out any loss trip time. While controller on uses look ahead knowledge entire route terms road grade, ...

The aim of this paper is the optimization velocity trajectories for electrical railway vehicles with focus on total energy consumption. On basis four fundamental operating modes—acceleration, cruising, coasting, and braking—energy-optimal are determined by optimizing sequence modes as well corresponding switching points. approach carried out in two consecutive steps. first step ensures complian...

This papers introduces an analytic method to define multistage launcher trajectories determine the payload mass that can be inserted in orbits of different semimajor axes and inclinations. evaluate gravity loss, which is main term subtracted Tziolkowski evaluation velocity provided by thrust a launcher. In method, are dependent on two parameters only: final flight-path angle γf at end gravity-t...

Abstract Track–vehicle severe interaction on track with small curve radius results in rail wear and corrugation, wheel polygonization, which drain considerable resources for grinding wheels re-profiling metro lines. To reduce the damage caused by track-vehicle interaction, paper analyzes reasons leading to then proposes an architecture of a vehicle independently rotating driven directly permane...

The prompt emission of short gamma-ray bursts (sGRBs) with known redshifts is analyzed using the model a multicolor blackbody, which interpreted as from nondissipative photosphere taking into account power-law jet structure and viewing geometry jet. We find nearly 69% 26% sample consistent blackbody pure model, respectively. Using this interpretation, we infer that 57% (18%) sGRBs in our are ob...