CHARACTERIZATION OF MICRO-DEFECTS IN NEARLY PERFECT CRYSTALS BY ANALYZING THE PENDELLÖSUNG FRINGES IN THE SECTION TOPOGRAPHS OF HIGH-ORDER REFLECTIONS

1990 ◽  
pp. 1529-1534 ◽  
Author(s):  
Satoshi IIDA ◽  
Hiroshi TAKENO ◽  
Yasuyoshi YAGOU ◽  
Nobuo KASAGI ◽  
Yoshimitsu SUGITA ◽  
...  
Keyword(s):  
High Order ◽  
Section Topographs

Characteristics in Response Integration and Bifurcation of a Forced Duffing Oscillator

2007 ◽  
Author(s):  
Jang-Der Jeng ◽  
Yuan Kang ◽  
Yeon-Pun Chang ◽  
Shyh-Shyong Shyr
Keyword(s):  
Applied Sciences ◽  
Phase Plane ◽  
Duffing Oscillator ◽  
High Order ◽  
Chaotic Motions ◽  
Integration Algorithm ◽  
High Order Harmonic ◽  
Stiffness And Damping

The Duffing oscillator is well-known models of nonlinear system, with applications in many fields of applied sciences and engineering. In this paper, a response integration algorithm is proposed to analyze high-order harmonic and chaotic motions in this oscillator for modeling rotor excitations. This method numerically integrates the distance between state trajectory and the origin in the phase plane during a specific period and predicted intervals with excitation periods. It provides a quantitative characterization of system responses and can replace the role of the traditional stroboscopic technique (Poincare´ section method) to observe bifurcations and chaos of the nonlinear oscillators. Due to the signal response contamination of system, thus it is difficult to identify the high-order responses of the subharmonic motion because of the sampling points on Poincare´ map too near each other. Even the system responses will be made misjudgments. Combining the capability of precisely identifying period and constructing bifurcation diagrams, the advantages of the proposed response integration method are shown by case studies. Applying this method, the effects of the change in the stiffness and the damping coefficients on the vibration features of a Duffing oscillator are investigated in this paper. From simulation results, it is concluded that the stiffness and damping of the system can effectively suppress chaotic vibration and reduce vibration amplitude.

scholarly journals On accurate high-order numerical derivatives computations for quantum chemistry purposes

2018 ◽  
Keyword(s):  
Quantum Chemistry ◽  
Finite Field ◽  
Numerical Differentiation ◽  
Field Method ◽  
High Order ◽  
Parameter Choice ◽  
Derivatives Of ◽  
Finite Field Method ◽  
Account Electron

Various molecular parameters in quantum chemistry could be computed as derivatives of energy over different arguments. Unfortunately, it is quite complicated to obtain analytical expression for characteristics that are of interest in the framework of methods that account electron correlation. Especially it relates to the coupled cluster (CC) theory. In such cases, numerical differentiation comes to rescue. This approach, like any other numerical method has empirical parameters and restrictions that require investigation. Current work is called to clarify the details of Finite-Field method usage for high-order derivatives calculation in CC approaches. General approach to the parameter choice and corresponding recommendations about numerical steadiness verification are proposed. As an example of Finite-Field approach implementation characterization of optical properties of fullerene passing process through the aperture of carbon nanotorus is given.

Characterization of intra-mode forward Brillouin scattering induced by vector high-order optical mode in nanofibers

2021 ◽  
pp. 127612
Author(s):  
Min Cao ◽  
Lin Huang ◽  
Min Tang ◽  
Yuean Mi ◽  
Wenhua Ren ◽  
...  
Keyword(s):  
Brillouin Scattering ◽  
High Order ◽  
Optical Mode

Characterization of high-order harmonic radiation on femtosecond and attosecond time scales

2004 ◽  
Vol 78 (7-8) ◽  
pp. 835-840 ◽  
Author(s):  
R. López-Martens ◽  
J. Mauritsson ◽  
P. Johnsson ◽  
K. Varjú ◽  
A. L’Huillier ◽  
...  
Keyword(s):  
Time Scales ◽  
High Order ◽  
Harmonic Radiation ◽  
High Order Harmonic

scholarly journals Characterization of a dual-gas multi-jet gas puff target for high-order harmonic generation using extreme ultraviolet shadowgraphy

2013 ◽  
Vol 31 (2) ◽  
pp. 219-227 ◽  
Author(s):  
P.W. Wachulak ◽  
L. Wegrzynski ◽  
A. Bartnik ◽  
T. Fok ◽  
R. Jarocki ◽  
...  
Keyword(s):  
Harmonic Generation ◽  
Extreme Ultraviolet ◽  
High Order ◽  
High Order Harmonic Generation ◽  
Density Profiles ◽  
Modes Of Operation ◽  
High Order Harmonic ◽  
Pulsed Injection ◽  
First Time

AbstractCharacterization measurements and modes of operation of a novel, dual-gas multi-jet target, developed for experiments on high-order harmonic generation, are presented. The target has been formed by pulsed injection of argon through a nozzle in a form of linearly oriented small orifices. The argon jets were separated with the helium jets formed by injection of helium through alternate orifices in the nozzle. The targets have been characterized by extreme ultraviolet backlighting at 13.5 nm wavelength. Density profiles for this type of targets have been obtained, to our knowledge, for the first time.

scholarly journals Ultrasonic Characterization of Texture

1988 ◽  
Vol 142 ◽  
Author(s):  
Y. Li ◽  
R. B. Thompson
Keyword(s):  
Orientation Distribution ◽  
Distribution Coefficients ◽  
High Order ◽  
New Technique ◽  
Ultrasonic Velocities ◽  
Ultrasonic Characterization ◽  
Cubic Crystallites ◽  
A New Technique ◽  
Rolled Plates

AbstractThis paper will propose a new technique to characterize texture of rolled plates of cubic crystallites. This technique uses information from ultrasonic velocities of high order plate mode to improve the estimation of orientation distribution coefficients (ODC's), especially W400. Also discussed will be the generalization of this technique to the case of hexagonal crystallites.

Characterization of spherical particles using high-order neural networks and scanning flow cytometry

2006 ◽  
Vol 102 (1) ◽  
pp. 62-72 ◽  
Author(s):  
Vladimir V. Berdnik ◽  
Konstantin Gilev ◽  
Alexander Shvalov ◽  
Valeri Maltsev ◽  
Valery A. Loiko
Keyword(s):  
Neural Networks ◽  
Flow Cytometry ◽  
High Order ◽  
Spherical Particles

scholarly journals Numerical characterization of local and global non-uniformities in the load distribution in ball screws

2021 ◽  
Author(s):  
Luca Sangalli ◽  
Aitor Oyanguren ◽  
Jon Larrañaga ◽  
Aitor Arana ◽  
Mikel Izquierdo ◽  
...  
Keyword(s):  
Load Distribution ◽  
High Order ◽  
Ball Screw ◽  
Computational Time ◽  
Ball Size ◽  
Numerical Characterization ◽  
Design Variables ◽  
Characteristic Features ◽  
Load Arrangement

AbstractLoad distribution in ball screws is a representation of the ball contact stress, and it is fundamental to understanding the behavior of these machine elements. This work aims to conduct a multi-variable analysis of the load distribution in ball screws. For this purpose, a numerical tool is developed for the generation and calculation of ball screw finite element (FE) models, which has been validated against the state of the art. This tool is based on the combination of an analytical contact model and the use of high-order FE models for the analysis of the load distribution of ball screws and stands out for its accuracy (less than 1% error against high-order FE models), adaptability, versatility (models are generated with more than 20 design variables and they can be introduced as components in larger models) and efficiency (being the computational time 1.25% of that of a high-order FE models) with respect to other existing models. Many different design variables (number of start threads, pitch, contact angle, ball size, slenderness and load arrangement) are studied in order to obtain a general characterization of the morphology of the load distribution in ball screws. Among them, the most influential variables on the load distribution and therefore on the structural behavior of ball screws are, load arrangement (with ratio r variations of up to 25% on the same ball screw) and slenderness (with ratio variations of up to 13% on ball screws with two turns of difference). The two most characteristic features, the non-uniformity at a local and global level are identified, along with as the possible causes of their appearance and the consequences that they may cause.

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