A time domain hybrid method for the coupling of two wires above the ground excited by electromagnetic pulses

2019 ◽  
Vol 62 (3) ◽  
pp. 1117-1124 ◽  
Author(s):  
Rui Huan ◽  
Cheng Liao ◽  
Zhihong Ye ◽  
Jie Luo
Keyword(s):  
Hybrid Method ◽  
Time Domain ◽  
Electromagnetic Pulses

Optimized Mooring Line Simulation Using a Hybrid Method Time Domain Scheme

2014 ◽  
Author(s):  
Niels Hørbye Christiansen ◽  
Per Erlend Torbergsen Voie ◽  
Jan Høgsberg ◽  
Nils Sødahl
Keyword(s):  
Hybrid Method ◽  
Time Domain ◽  
Computation Time ◽  
Mooring Line ◽  
Mooring Lines ◽  
Fem Model ◽  
Input Variables ◽  
The Time Domain ◽  
The Cost ◽  
Short Time

Dynamic analyses of slender marine structures are computationally expensive. Recently it has been shown how a hybrid method which combines FEM models and artificial neural networks (ANN) can be used to reduce the computation time spend on the time domain simulations associated with fatigue analysis of mooring lines by two orders of magnitude. The present study shows how an ANN trained to perform nonlinear dynamic response simulation can be optimized using a method known as optimal brain damage (OBD) and thereby be used to rank the importance of all analysis input. Both the training and the optimization of the ANN are based on one short time domain simulation sequence generated by a FEM model of the structure. This means that it is possible to evaluate the importance of input parameters based on this single simulation only. The method is tested on a numerical model of mooring lines on a floating off-shore installation. It is shown that it is possible to estimate the cost of ignoring one or more input variables in an analysis.

scholarly journals Locating the frozen–unfrozen interface in soils using time-domain reflectometry

1982 ◽  
Vol 19 (4) ◽  
pp. 511-517 ◽  
Author(s):  
T. H. W. Baker ◽  
J. L. Davis ◽  
H. N. Hayhoe ◽  
G. C. Topp
Keyword(s):  
Transmission Lines ◽  
Time Domain ◽  
Freezing Temperature ◽  
Time Domain Reflectometry ◽  
Temperature Measurements ◽  
Soil Freezing ◽  
Electromagnetic Pulses ◽  
The Time Domain ◽  
Time Domain Reflectometer ◽  
Liquid And Solid Phases

The time-domain reflectometry technique was compared with the temperature measurement method for locating the frozen–unfrozen interface in water and sandy soils. This technique depends on the high-frequency (1–1000 MHz) electrical properties of water that change significantly and abruptly between the liquid and solid phases. Parallel wire transmission lines were inserted into the soil to guide electromagnetic pulses produced by a time-domain reflectometer (TDR). The frozen–unfrozen interface produced reflections measured by the TDR which were in turn used to locate the interface as it moved along the transmission line. In the laboratory it was possible to locate the interface using the TDR to within ±0.5 cm and in the field to within ±2.4 cm. These errors were equal to those associated with the temperature measurements. Keywords: soil freezing, temperature measurements, dielectric constant, time-domain reflectometry.

A time-domain hybrid method combining the finite-difference and physical-optics methods

1999 ◽  
Vol 21 (2) ◽  
pp. 82-88 ◽  
Author(s):  
F. Le Bolzer ◽  
R. Gillard ◽  
J. Citerne ◽  
V. Fouad Hanna ◽  
M. F. Wong
Keyword(s):  
Finite Difference ◽  
Hybrid Method ◽  
Time Domain ◽  
Physical Optics

scholarly journals Time domain model of the resonance-based electromagnetic pulses emission system

2019 ◽  
Vol 28 ◽  
pp. 01001
Author(s):  
Mikołaj Nowak ◽  
Kazimierz Jakubiuk ◽  
Daniel Kowalak ◽  
Mirosław Wołoszyn
Keyword(s):  
Electromagnetic Field ◽  
Experimental Research ◽  
Time Domain ◽  
Domain Model ◽  
Time Domain Simulation ◽  
Resonance System ◽  
Field Pulse ◽  
Electromagnetic Pulses ◽  
Emission Efficiency ◽  
Emission System

In the literature, the emission properties of the electromagnetic field pulse systems based on high voltage antennas (HVR) have been widely described. In order to increase the emission efficiency by extending duration and increasing amplitude of the impulse it is possible to use a resonance system tuned to the parameters of the signal shaped in the pulse forming circuit. The synthesis of a time-domain simulation model of a complex electromagnetic pulses emission system and its verification by experimental research has been presented in this paper.

Sign in / Sign up

Export Citation Format

Share Document