Influence of Beam Polarizations on Evaporative Laser Cutting Nonmetallic Materials within High Absorptance

2009 ◽  
Vol 626-627 ◽  
pp. 363-368
Author(s):  
Xiao Zhu Xie ◽  
J.G. Lu ◽  
Xin Wei ◽  
W. Hu
Keyword(s):  
Theoretical Analysis ◽  
Laser Beam ◽  
Ray Tracing ◽  
Laser Cutting ◽  
Three Dimensional ◽  
Coupling Model ◽  
Experimental Results ◽  
Multiple Reflections ◽  
Set Up ◽  
Tracing Method

The three dimensional (3D) coupling model is set up for analyzing the energy reflection and absorption on the kerf using ray tracing method after the laser beam cutting nonmetallic materials with high absorptance through multiple reflections. The laser beam characterized by focused gauss beam and fresnel absorption on the kerf are taken into account. The influences of the polarization on the absorbed intensity both in the front and the two walls are also discussed. Results indicate the differences of absorptive intensity among the three polarized lights are relatively small compared to metal. Thus, the polarization has little effects on the kerf of nonmetallic materials with high absorptance. The experimental results also agree well with the theoretical analysis.

Research on Outdoor Positioning Based on Ray Tracing Method

2014 ◽  
Vol 556-562 ◽  
pp. 3039-3042
Author(s):  
Xian Qiang Peng
Keyword(s):  
Wave Propagation ◽  
Ray Tracing ◽  
Radio Waves ◽  
Complex Environment ◽  
Simulation Experiments ◽  
Outdoor Environments ◽  
Positioning Method ◽  
Tracking Point ◽  
Set Up ◽  
Tracing Method

GPS can’t detect the signal because of the cell complex environment in the outdoor and poor radio wave propagation conditions, so that the positioning result is not ideal. However, the positioning method using the ray tracing prediction of radio waves, the tracking point of the scene from all the source radiation, record the relevant parameters, and then positioned within the microcell environment can satisfy the demand. The principle of ray tracing was firstly introduced in this paper, then an outdoor positioning model was set up, finally, the corresponding simulation experiments was implemented to demonstrate the effectiveness of ray tracing positioning in the outdoor environments.

Effects of convection in laser-guided transportation

2004 ◽  
Vol 218 (7) ◽  
pp. 775-782
Author(s):  
L Chen ◽  
Y Yan ◽  
R Zhang
Keyword(s):  
Laser Beam ◽  
Three Dimensional ◽  
Biological Research ◽  
Convection Flow ◽  
Direct Write ◽  
Laser Guidance ◽  
Element Analysis ◽  
Research Areas ◽  
Fea Model ◽  
Set Up

Weak focusing laser beams can guide micrometre-sized beads to direct-write two-dimensional patterns or three-dimensional structures. Applications based on laser guidance have been found in many fields including biological research areas. This paper discusses the effects of convection, which is the main disturbance during laser-guided transportation. The heat generated by optical absorption causes the convection flow, as observed in experiments. To investigate this convection flow, a finite element analysis (FEA) model was set up and computation under different heat load conditions was carried out. The results show that the convection flow velocity at the laser beam centre has a direct proportional relation to the incident power and varies with the position of the laser beam.

scholarly journals Validation of Three-Dimensional Ray-Tracing Algorithm for Indoor Wireless Propagations

2011 ◽  
Vol 2011 ◽  
pp. 1-5 ◽  
Author(s):  
Majdi Salem ◽  
Mahamod Ismail ◽  
Norbahiah Misran
Keyword(s):  
Ray Tracing ◽  
Electromagnetic Waves ◽  
Three Dimensional ◽  
Prediction Method ◽  
Access Point ◽  
Network Access ◽  
Multiple Reflections ◽  
Indoor Wireless ◽  
3D Ray Tracing ◽  
Tracing Algorithm

A 3D ray tracing simulator has been developed for indoor wireless networks. The simulator uses geometrical optics (GOs) to propagate the electromagnetic waves inside the buildings. The prediction technique takes into account multiple reflections and transmissions of the propagated waves. An interpolation prediction method (IPM) has been proposed to predict the propagated signal and to make the ray-tracing algorithm faster, accurate, and simple. The measurements have been achieved by using a single Wi-Fi network access point as a transmitter and a laptop as a receiver. Measured data had been collected at different positions in indoor environment and compared with predicted signals. The comparison of the predicted and measured received signals gave root mean square error of 2.96 dB and std. deviation of 2.98 dB.

scholarly journals An Efficient 3-D Ray Tracing Method: Prediction of Indoor Radio Propagation at 28 GHz in 5G Network

Electronics ◽  
2019 ◽  
Vol 8 (3) ◽  
pp. 286 ◽  
Author(s):  
Ferdous Hossain ◽  
Tan Geok ◽  
Tharek Rahman ◽  
Mohammad Hindia ◽  
Kaharudin Dimyati ◽  
...  
Keyword(s):  
Ray Tracing ◽  
Three Dimensional ◽  
Measurement Data ◽  
Path Loss ◽  
Simulation Software ◽  
Ray Tracing Method ◽  
Fifth Generation ◽  
Indoor Radio ◽  
5G Network ◽  
Tracing Method

Millimeter wave technology will be dominating the fifth-generation networks due to the clear advantage of higher frequency bands and hence wider spectrum. In this paper, the indoor radio wave propagation at 28 GHz is studied by developing an efficient three-dimensional ray tracing (ETRT) method. The simulation software based on the ETRT model has been verified by measurement data. The received signal strength indication and path loss have shown significant agreement between simulation and measurement. Compared with the conventional shooting bouncing ray tracing method, the proposed ETRT method has better agreement with measurement data.

Evaluation of influence of target location on robot repeatability

Robotica ◽  
2000 ◽  
Vol 18 (4) ◽  
pp. 443-449 ◽  
Author(s):  
Raziel Riemer ◽  
Yael Edan
Keyword(s):  
Error Analysis ◽  
Target Location ◽  
Kinematic Model ◽  
Three Dimensional ◽  
Experimental Results ◽  
Target Point ◽  
Analysis Model ◽  
Significant Statistical Difference ◽  
Optimal Target ◽  
Set Up

This paper evaluates the influence of target location on robot repeatability. An experiment was set up to analyze the effect of the three-dimensional target location on robot repeatability. An error-analysis model to determine repeatability based on the robot's kinematic model and known robot parameters was developed. Experimental results indicated that there was a significant statistical difference between repeatability at different locations in the workspace and that the height of the target point influenced repeatability. Experimental results tended to those derived from the error-analysis kinematic model. Hence, to determine the optimal target location, there is no need for extensive experimentation; instead, only a few target points can be sampled and compared to an error-analysis model.

scholarly journals Verification of a two-dimensional/three-dimensional hybrid ray-tracing method for spatiotemporal channel modeling

Radio Science ◽  
2001 ◽  
Vol 36 (1) ◽  
pp. 53-66 ◽  
Author(s):  
Houtao Zhu ◽  
Jun-ichi Takada ◽  
Kiyomichi Araki ◽  
Takehiko Kobayashi
Keyword(s):  
Ray Tracing ◽  
Three Dimensional ◽  
Channel Modeling ◽  
Two Dimensional ◽  
Ray Tracing Method ◽  
Tracing Method
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