OBSERVATION OF THE COLLINEAR MULTI-BODY DECAYS IN THE REACTION 238U+4He (40 MEV)

2008 ◽  
Vol 17 (10) ◽  
pp. 2226-2230 ◽  
Author(s):  
◽  
YU. PYATKOV
Keyword(s):  
Inelastic Scattering ◽  
Flight Path ◽  
Scission Point ◽  
Magic Clusters ◽  
A Chain ◽  
The Masses ◽  
Multi Body

Two different modes of the multibody collinear decay from the reaction 238 U +4 He (40 MeV ) are discussed. Basing on the masses of three detected fragments one can come to conclusion that the decaying system in each mode looks like a chain consisting of two or three magic clusters respectively. Some of the clusters involved undergo "second" clusterisation in the scission point leading to formation of dinuclear molecules. These latter can disintegrate via inelastic scattering on the materials on the flight path.

A 3D Multi-Body Dynamics Model for Chain-Type Continuously Variable Unit

2017 ◽  
Author(s):  
Mohammad A. Hotait ◽  
Avinash Singh
Keyword(s):  
Three Dimensional ◽  
Operating Conditions ◽  
Speed Ratio ◽  
3 Dimensional ◽  
Three Dimensional Representation ◽  
Static Performance ◽  
Torque Capacity ◽  
A Chain ◽  
Multi Body ◽  
Chain Type

This paper presents a new 3-dimensional multi-body dynamic model of a chain-type continuously variable unit (CVU). The modeling requirements and assumptions are presented first. Then, the paper discusses the approaches developed to mathematically represent the chain, pulleys, and their interactions in terms of contact and friction. Three dimensional representation of the chain is given. Actual geometries of the pins and pulleys are captured, including crowning on either member. The model is then used to investigate the effects of different operating conditions, including speed ratio and torque, on the quasi-static performance of a CVU. Several metrics are discussed to characterize the behavior of an example CVU under practical operating conditions; these include torque capacity and the ratio of clamping forces. The predictions presented show the sensitivity of the model to these operating conditions. Finally, trends that describe the CVU quasi-static behavior are explained in context of the parameters studied.

Sequential and Near-Simultaneous Multi-Body Collisions

2004 ◽  
Author(s):  
D. Dane Quinn ◽  
Kalyan Bairavarasu
Keyword(s):  
Initial Conditions ◽  
Coefficient Of Restitution ◽  
Initial Configuration ◽  
Collision Model ◽  
Sufficient Distance ◽  
Initial Spacing ◽  
Compliance Model ◽  
The Masses ◽  
Multi Body ◽  
Impact Duration

This work considers a three mass collision model with finite-time, compliant contacts. If the masses are initially separated by a sufficient distance, the collision sequence is sequential, that is, comprised of a sequence of pairwise impacts. The final velocities of each mass are then independent of the specific initial spacing. In contrast, if the initial spacing between the masses is sufficiently small there exists an interval during which the three masses interact simultaneously. In this instance the final velocity state also depends on the initial configuration of the system. Given an assumed impact duration and coefficient of restitution for a pairwise collision, a two-dimensional map is derived to describe those initial conditions that lead to pairwise sequences. Finally, for a specific nonlinear compliance model the variation in the final velocities is characterized in terms of the initial configuration and velocity state of the system.

Energy Control of Nonlinear Non-Homogeneous Chains

2013 ◽  
Author(s):  
Firdaus E. Udwadia ◽  
Harshavardhan Mylapilli
Keyword(s):  
Degrees Of Freedom ◽  
Energy State ◽  
Fundamental Equation ◽  
Constrained Motion ◽  
Energy Control ◽  
Spring Element ◽  
Fundamental Equation Of Mechanics ◽  
A Chain ◽  
Control Forces ◽  
The Masses

In this paper, we consider the problem of energy control of an n-degrees-of-freedom system consisting of a chain of masses wherein each of the masses is connected to its neighboring mass with the help of a nonlinear memoryless spring element. The qualitative nature of the nonlinearity in each of the spring elements can, in general, be different. Both fixed-fixed and fixed-free boundary conditions are considered. The energy control problem is approached from a new perspective — that of constrained motion. For a given set of masses at which the control is to be applied, explicit closed form expressions for the nonlinear control forces are derived by using the fundamental equation of mechanics. Through the use of the invariance principle, we show that these control forces provide global asymptotic convergence to any ‘given’ non-zero energy state provided that the first mass, or the last mass, or alternately, any two consecutive masses in the chain are included in the subset of masses that are controlled. The results obtained in this paper are, in general, applicable to any finite degrees-of-freedom, fixed-fixed or fixed-free nonlinear chain whose spring potentials are described by a class of twice continuously differentiable, strictly convex functions, which possess a global minimum at zero displacement, with zero curvature possibly only at zero displacement.

GEOMETRICALLY INDUCED NONLINEAR DYNAMICS IN ONE-DIMENSIONAL LATTICES

2008 ◽  
Vol 18 (08) ◽  
pp. 2471-2476
Author(s):  
M. HAMILTON ◽  
O. F. DE ALCANTARA BONFIM
Keyword(s):  
Coupled Oscillators ◽  
Domain Walls ◽  
Equations Of Motion ◽  
Geometric Constraints ◽  
One Dimensional ◽  
Long Wavelength ◽  
Simple Lattice ◽  
A Chain ◽  
The Stability ◽  
The Masses

We present a simple lattice model consisting of a chain of coupled oscillators, where their masses are interconnected by linear springs and allowed to move along a common axis, as in a monorail. In the transverse direction each mass is also attached to two other springs, one on each side of the mass. The ends of these springs are kept at fixed positions. The nonlinearity in the model arises from the geometric constraints imposed on the motion of the masses, as well as from the configuration of the springs, where in the transverse directions the springs are either in the extended or compressed state depending on the position of the mass. Under these conditions we show that solitary waves (domain walls) are present in the system. In the long wavelength limit an analytical solution for these nonlinear waves is found. Numerical integrations of the equations of motion in the full discrete system are also performed to analyze the stability of the domain wall solution. Nonlinear supratransmission is also shown to exist in the model and a discussion of mechanism is presented.

Shock and Vibration Isolation Using Internally Rotating Masses

2015 ◽  
Author(s):  
Eric Smith ◽  
Al Ferri
Keyword(s):  
Energy Transfer ◽  
Kinetic Energy ◽  
Numerical Simulations ◽  
Vibration Isolation ◽  
Viscous Damping ◽  
Targeted Energy Transfer ◽  
Axial Vibration ◽  
Transmitted Force ◽  
A Chain ◽  
The Masses

This paper considers the use of a chain of springs and masses to reduce the transmission of shock and vibration through the system. The masses are equipped with internally rotating masses that absorb some of the axial vibration into internal kinetic energy of the masses. The internal masses have viscous damping, but no elastic or gravitational restraint. Previous research has shown that a single cart system attached to a vibrating structure can help mitigate shock through targeted energy transfer. This paper examines the potential for shock isolation provided by a chain of such systems. Through numerical simulations, tradeoffs are examined between displacement and transmitted force.

V.—The Structure and Later Geological History of New Zealand

1916 ◽  
Vol 3 (7) ◽  
pp. 314-320 ◽  
Author(s):  
C. A. Cotton
Keyword(s):  
New Zealand ◽  
Sea Level ◽  
Deep Water ◽  
Geological History ◽  
Great Weight ◽  
Mountain Ranges ◽  
Wide Acceptance ◽  
History Of ◽  
A Chain ◽  
The Masses

Supported by the great weight of Hutton's authority, his views, with which those of Haast and the early views of Hector were in general agreement, have gained wide acceptance, notwithstanding the opposition of McKay. Marshall, for example, as late as 1911 wrote as follows: “The great elevation [Mesozoic orogenic movement] was succeeded by nearly as great a depression. The majestic mountain ranges were gradually lowered until nothing but a chain of islands showed above sea level. To what a great extent this movement prevailed is seen at Lake Te Anau, where the Oamaru formation, some 3,000 feet thick, rises to the tops of the mountains. At Wakatipu and in the Rangitata valley the Oamaru rocks are found in the recesses of the mountains. In the Trelissick basin and between the masses of the Kaikoura ranges there was deep water. The valleys of the tributaries of the Buller are filled with Oamaru sediments.”

Mass–spring–damper modelling of the human body to study running and hopping – an overview

2011 ◽  
Vol 225 (12) ◽  
pp. 1121-1135 ◽  
Author(s):  
A A Nikooyan ◽  
A A Zadpoor
Keyword(s):  
Mechanical Properties ◽  
Human Body ◽  
Soft Tissues ◽  
Equations Of Motion ◽  
Future Research ◽  
Advantages And Disadvantages ◽  
The Masses ◽  
Mass Spring ◽  
Stiffness And Damping ◽  
Multi Body

Several mass–spring–damper models have been developed to study the response of the human body to the collision with the ground during hopping, trotting, or running. The mass, spring, and damper elements represent the masses, stiffness properties, and damping properties of hard and soft tissues. The masses that models are composed of are connected to each other via springs and dampers. The present paper reviews the various types of mass–spring–damper models including one-body and multi-body models. The models are further categorized as being either passive or active. In passive models, the mechanical properties (stiffness and damping) of soft tissues remain constant regardless of the type of footwear, ground stiffness, etc. In active models, the mechanical properties adapt to external loads. The governing equations of motion of all models as well as their parameters are presented. The specific ways that the models take account of the shoe–ground interactions are discussed as well. The methods used for determination of different modelling parameters are briefly surveyed. The advantages and disadvantages of the different types of mass–spring–damper models are also discussed. The paper concludes with a brief discussion of possible future research trends in the area of mass–spring–damper modelling.

scholarly journals Soft gravitational radiation from multi-body collisions

2021 ◽  
Vol 2021 (11) ◽  
Author(s):  
Andrea Addazi ◽  
Kaiqiang Alan Zeng
Keyword(s):  
Energy Flux ◽  
Gravitational Radiation ◽  
Radiation Flux ◽  
Radiation Energy ◽  
Simple Expression ◽  
Quantum Spin ◽  
Particle Collisions ◽  
The Masses ◽  
Multi Body ◽  
Universal Expression

Abstract We derive a universal expression for the gravitational radiation energy spectrum dEGW/dω at sub-leading order emitted from a generic gravitational hard scattering of multi-particles or multi-bodies. Our result includes all $$ \mathcal{O} $$ O (ω) corrections to the gravitational radiation flux from a generic 2 → N collision, in both the cases of massless and massive particles/bodies. We also show the dependence of the radiation energy flux by the quantum spin in case of particle collisions. Then, we consider the specific case of a gravitational elastic scattering of two massive bodies, i.e. m + M → m + M with m, M the masses of the two bodies respectively. We demonstrate that in this case all $$ \mathcal{O} $$ O (ω) contributions to the energy flux exactly cancel each others. Nevertheless, we also show that, for a 2 → 2 inelastic scattering, the inclusion of sub-leading soft gravitons leads to a not zero radiation flux, having a simple expression in certain asymptotic regimes. Our results can be applied to the case of Black Hole collisions with possible testable implications in gravitational waves physics.

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