Delta distribution of electronegative plasma predicted by reformed “spring oscillator” dynamic equation with dispersing force

AbstractBy using of generalized Opial’s type inequality on time scales, a new oscillation criterion is given for a singular initial-value problem of second-order dynamic equation on time scales. Some oscillatory results of its generalizations are also presented. Example with various time scales is given to illustrate the analytical findings.

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Soliton turbulence in electronegative plasma due to head-on collision of multi solitons

Zeitschrift für Naturforschung A ◽

10.1515/zna-2020-0186 ◽

2020 ◽

Vol 75 (12) ◽

pp. 999-1007

Author(s):

Rustam Ali ◽

Anjali Sharma ◽

Prasanta Chatterjee

Keyword(s):

Wave Field ◽

Soliton Solutions ◽

Negative Ions ◽

First Integral ◽

Statistical Properties ◽

Charged Dust ◽

Bilinear Method ◽

Electronegative Plasma ◽

Kdv Equations ◽

First Four Moments

AbstractHead-on interaction of four dust ion acoustic (DIA) solitons and the statistical properties of the wave field due to head-on interaction of solitons moving in opposite direction is studied in the framework of two Korteweg de Vries (KdV) equations. The extended Poincaré–Lighthill–Kuo (PLK) method is applied to obtain two opposite moving KdV equations from an unmagnetized four component plasma model consisting of Maxwellian negative ions, cold mobile positive ions, κ-distributed electrons and positively charged dust grains. Hirota’s bilinear method is adopted to obtain two-soliton solutions of both the KdV equations and accordingly act of soliton turbulence is presented due to head-on collision of four solitons. The amplitude and shape of the resultant wave profile at the point of strongest interaction are obtained. To see the effect of head-on collision on the statistical properties of wave field the first four moments are computed. It is observed that the head-on collision has no effect on the first integral moment while the second, third and fourth moments increase in the dominant interaction region of four solitons, which is a clean indication of soliton turbulence.

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Solitary waves in a dusty adiabatic electronegative plasma

Journal of Plasma Physics ◽

10.1017/s0022377809990614 ◽

2010 ◽

Vol 76 (3-4) ◽

pp. 409-418 ◽

Cited By ~ 7

Author(s):

A. A. MAMUN ◽

K. S. ASHRAFI ◽

M. G. M. ANOWAR

Keyword(s):

Solitary Waves ◽

Vries Equation ◽

Negative Ions ◽

Finite Amplitude ◽

Reductive Perturbation Method ◽

Charged Dust ◽

Electronegative Plasma ◽

Ion Acoustic ◽

Basic Features ◽

Electronegative Plasmas

AbstractThe dust ion-acoustic solitary waves (SWs) in an unmagnetized dusty adiabatic electronegative plasma containing inertialess adiabatic electrons, inertial single charged adiabatic positive and negative ions, and stationary arbitrarily (positively and negatively) charged dust have been theoretically studied. The reductive perturbation method has been employed to derive the Korteweg-de Vries equation which admits an SW solution. The combined effects of the adiabaticity of plasma particles, inertia of positive or negative ions, and presence of positively or negatively charged dust, which are found to significantly modify the basic features of small but finite-amplitude dust-ion-acoustic SWs, are explicitly examined. The implications of our results in space and laboratory dusty electronegative plasmas are briefly discussed.

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Task-based torque minimization of a 3-PṞR spherical parallel manipulator

Robotica ◽

10.1017/s026357472100062x ◽

2021 ◽

pp. 1-30

Author(s):

Soheil Zarkandi

Keyword(s):

Closed Form ◽

Dynamic Modeling ◽

Dynamic Equation ◽

Parallel Manipulator ◽

Optimization Problem ◽

Dynamic Constraints ◽

Part C ◽

Euler Approach ◽

Three Degree Of Freedom ◽

Spherical Parallel Manipulator

Abstract A comprehensive dynamic modeling and actuator torque minimization of a new symmetrical three-degree-of-freedom (3-DOF) 3-PṞR spherical parallel manipulator (SPM) is presented. Three actuating systems, each of which composed of an electromotor, a gearbox and a double Rzeppa-type driveshaft, produce input torques of the manipulator. Kinematics of the 3-PṞR SPM was recently studied by the author (Zarkandi, Proc. Inst. Mech. Eng. Part C J. Mech. Eng. Sci. 2020, https://doi.org/10.1177%2F0954406220938806). In this paper, a closed-form dynamic equation of the manipulator is derived with the Newton–Euler approach. Then, an optimization problem with kinematic and dynamic constraints is presented to minimize torques of the actuators for implementing a given task. The results are also verified by the SimMechanics model of the manipulator.

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Electrostatic wave breaking limit in a cold electronegative plasma with non-Maxwellian electrons

Scientific Reports ◽

10.1038/s41598-021-85228-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

I. S. Elkamash ◽

I. Kourakis

Keyword(s):

Wave Breaking ◽

Density Ratio ◽

Negative Ions ◽

First Integral ◽

Energy Balance Equation ◽

Plasma Parameters ◽

Ion Density ◽

Electrostatic Wave ◽

Nonthermal Electrons ◽

Electronegative Plasma

AbstractA one-dimensional multifluid hydrodynamic model has been adopted as basis for an investigation of the role of suprathermal electrons on the wave breaking amplitude limit for electrostatic excitations propagating in an electronegative plasma. A three-component plasma is considered, consisting of two inertial cold ion populations of opposite signs, evolving against a uniform background of (non-Maxwellian) electrons. A kappa-type (non-Maxwellian) distribution function is adopted for the electrons. By employing a traveling wave approximation, the first integral for the fluid-dynamical system has been derived, in the form of a pseudo-energy balance equation, and analyzed. The effect of intrinsic plasma parameters (namely the ion density ratio, the ion mass ratio, and the superthermal index of the nonthermal electrons) on the wave breaking amplitude limit is explored, by analyzing the phase space topology of the associated pseudopotential function. Our results are relevant to particle acceleration in Space environments and to recent experiments based on plasma-based accelerator schemes, where the simultaneous presence of negative ions and nonthermal electrons may be observed.

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