scholarly journals Use of Unmanned Aerial Assault Vehicles (UAAV) as an Asymmetric Factor

2014 ◽  
Vol 2 (4) ◽  
pp. 101
Author(s):  
Alper Alpaslan Eker ◽  
Eray Sallar ◽  
Yasin Turan
Keyword(s):  
Asymmetric Factor

scholarly journals A Novel Method for Tooth Bending Stress Calculation of Gears With Asymmetric Teeth

2021 ◽  
Author(s):  
Oguz DOGAN ◽  
Celalettin YUCE ◽  
Fatih KARPAT
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Experimental Studies ◽  
Element Model ◽  
Bending Stress ◽  
Element Analysis ◽  
Stress Calculation ◽  
Bending Stresses ◽  
New Equation ◽  
Asymmetric Factor

Abstract Today, gear designs with asymmetric tooth profiles offer essential solutions in reducing tooth root stresses of gears. Although numerical, analytical, and experimental studies are carried out to calculate the bending stresses in gears with asymmetric tooth profiles a standard or a simplified equation or empirical statement has not been encountered in the literature. In this study, a novel bending stress calculation procedure for gears with asymmetric tooth profiles is developed using both the DIN3990 standard and the finite element method. The bending stresses of gears with symmetrical profile were determined by the developed finite element model and was verified by comparing the results with the DIN 3990 standard. Using the verified finite element model, by changing the drive side pressure angle between 20° and 30° and the number of teeth between 18 and 100, 66 different cases were examined and the bending stresses in gears with asymmetric profile were determined. As a result of the analysis, a new asymmetric factor was derived. By adding the obtained asymmetric factor to the DIN 3390 formula, a new equation has been derived to be used in tooth bending stresses of gears with asymmetric profile. Thanks to this equation, designers will be able to calculate tooth bending stresses with high precision in gears with asymmetric tooth profile without the need for finite element analysis.

X-ray phase contrast imaging study of activated carbon/carbon composite

1999 ◽  
Vol 590 ◽  
Author(s):  
Kenji Kobayashi ◽  
Koichi Izumi ◽  
Hidekazu Kimura ◽  
Shigeru Kimura ◽  
Tomoaki Ohira ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Spatial Resolution ◽  
Phase Contrast ◽  
Imaging Study ◽  
Carbon Composite ◽  
Bragg Diffraction ◽  
Magnification Factor ◽  
Contrast Imaging ◽  
X Ray ◽  
Asymmetric Factor

ABSTRACTWe have obtained the x-ray phase contrast images of the activated carbon/carbon (AC/C) composite used as electrodes in an electric double-layer capacitor (EDLC). To improve the spatial resolution, the beam size of x-ray transmitted from a sample were expanded by using asymmetric Bragg diffraction (asymmetric factor b) of analyzer crystal. Since the analyzer crystals were placed in (+, -) arrangements in both vertical and horizontal directions, the total magnification factor was 1/b2 for each direction. By using the 511 asymmetric Bragg diffraction of Si (100) analyzer with an asymmetric factor of 0.207, we could obtain the magnification factor of about 23.3. We applied this optical system to the AC/C composite. The phase contrast image corresponding to the carbon particles with the diameter of about 10 μm could be detected with the spatial resolution of 5 μm. Furthermore, we also obtained realtime images of bubble formation and movement during the overcharging of an EDLC with the time resolution of 30 frames number per second.

scholarly journals Double asymmetric percolation drives a quadruple transition in sexual contact networks

2019 ◽  
Author(s):  
Hongyu Zheng ◽  
Xiangrui Zeng
Keyword(s):  
Sexual Contact ◽  
Graph Structure ◽  
Mosquito Vectors ◽  
Percolation Process ◽  
Contact Networks ◽  
Scale Free ◽  
Scale Free Networks ◽  
Control And Prevention ◽  
Asymmetric Factor ◽  
Insight Into

AbstractSince 2007, ZIKV outbreaks have been occurring around the world. While ZIKV is mainly spread by mosquito vectors, transmission via sex activities enables the virus to spread in regions without mosquito vectors. Modeling the patterns of ZIKV outbreak in these regions remain challenging. We consider age as an asymmetric factor in transmitting ZIKV, in addition to gender as seen in previous literature, and modify the graph structure for better modeling of such patterns. We derived our results by both solving the underlying differential equations and simulation on population graph. Based on a double asymmetric percolation process on sexual contact networks. we discovered a quadruple ZIKV epidemic transition. Moreover, we explored the double asymmetric percolation on scale-free networks. Our work provides more insight into the ZIKV transmission dynamics through sexual contact networks, which may potentially provide better public health control and prevention means in a ZIKV outbreak.

Springing and Ringing Response of Offshore Triceratops

2015 ◽  
Author(s):  
Srinivasan Chandrasekaran ◽  
Jamshed Nassery
Keyword(s):  
Wave Height ◽  
Significant Wave Height ◽  
Numerical Study ◽  
Irregular Waves ◽  
Impact Loads ◽  
Beat Phenomenon ◽  
Average Wave ◽  
Gradual Decay ◽  
Asymmetric Factor ◽  
Jonswap Spectrum

This paper presents a numerical study of ringing and springing response of a relatively new Offshore Triceratops. The platform is subjected to irregular waves using JONSWAP spectrum by varying the significant wave height, average wave period, vertical asymmetric factor and the over shoot parameter. Strongly asymmetric waves, which are capable of causing impact loads on triceratops, are used to simulate ringing in offshore triceratops. Heave response shows bursts but there are no rapid built ups. Gradual decay, which is seen in the present case, resembles a beat phenomenon.

scholarly journals Adaptive Control for Pure-Feedback Nonlinear Systems Preceded by Asymmetric Hysteresis

Energies ◽  
2019 ◽  
Vol 12 (24) ◽  
pp. 4675 ◽  
Author(s):  
Xiaohuan Lai ◽  
Haipeng Pan ◽  
Xinlong Zhao
Keyword(s):  
Adaptive Control ◽  
Nonlinear Systems ◽  
Control Method ◽  
Controller Design ◽  
State Variables ◽  
External Disturbances ◽  
Hysteresis Nonlinearity ◽  
Control Scheme ◽  
Factor State ◽  
Asymmetric Factor

An adaptive control scheme is proposed for a class of uncertain pure-feedback nonlinear systems preceded by asymmetric hysteresis nonlinearity. The asymmetric property is described by the modified Bouc-Wen model based on the proposed asymmetric factor. State variables in the controller design are directly replaced with nonaffine functions to address the control problem caused by nonaffine appearance. Moreover, the control method can handle systems with external disturbances and guarantee the global stability of all the signals in the closed-loop system. The feasibility of the control scheme is verified by a simulation example and experimental results.

scholarly journals An Asymmetric Hysteresis Model and Parameter Identification Method for Piezoelectric Actuator

2014 ◽  
Vol 2014 ◽  
pp. 1-14 ◽  
Author(s):  
Haichen Qin ◽  
Ningbin Bu ◽  
Wei Chen ◽  
Zhouping Yin
Keyword(s):  
Parameter Identification ◽  
Smart Materials ◽  
Model Parameters ◽  
Hysteresis Model ◽  
Pzt Actuator ◽  
Modified Particle Swarm Optimization ◽  
Identification Method ◽  
Model Based ◽  
Asymmetric Factor ◽  
Hysteresis Behaviour

Hysteresis behaviour degrades the positioning accuracy of PZT actuator for ultrahigh-precision positioning applications. In this paper, a corrected hysteresis model based on Bouc-Wen model for modelling the asymmetric hysteresis behaviour of PZT actuator is established by introducing an input biasφand an asymmetric factorΔΦinto the standard Bouc-Wen hysteresis model. A modified particle swarm optimization (MPSO) algorithm is established and realized to identify and optimize the model parameters. Feasibility and effectiveness of MPSO are proved by experiment and numerical simulation. The research results show that the corrected hysteresis model can represent the asymmetric hysteresis behaviour of the PZT actuator more accurately than the noncorrected hysteresis model based on the Bouc-Wen model. The MPSO parameter identification method can effectively identify the parameters of the corrected and noncorrected hysteresis models. Some cases demonstrate the corrected hysteresis model and the MPSO parameter identification method can be used to model smart materials and structure systems with the asymmetric hysteresis behaviour.

Sign in / Sign up

Export Citation Format

Share Document