Simplified Analysis of a Coherent THz Cherenkov Radiation Generator

Contradictious results published by different authors about the dynamics of systems with random parameters have been examined. Statistical analysis of the simple 1st order system proves that the random parameter can cause a systematic difference in the dynamic behavior that cannot be (in general) described by the usual constant-parameter model with the additive noise at the output.

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Simplified analysis and design for elevated temperature components of Monju

Nuclear Engineering and Design ◽

10.1016/0029-5493(87)90008-2 ◽

1987 ◽

Vol 98 (3) ◽

pp. 305-317 ◽

Cited By ~ 34

Author(s):

Kunihiro Iida ◽

Yasuhide Asada ◽

Kunio Okabayashi ◽

Takashi Nagata

Keyword(s):

Elevated Temperature ◽

Analysis And Design ◽

Simplified Analysis

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Cherenkov radiation of the fast magnetoacoustic waves in the non-uniform magnetospheric plasma

Physics of Plasmas ◽

10.1063/5.0035904 ◽

2021 ◽

Vol 28 (2) ◽

pp. 022901

Author(s):

Dmitri Yu. Klimushkin ◽

Pavel N. Mager

Keyword(s):

Cherenkov Radiation ◽

Magnetospheric Plasma ◽

Magnetoacoustic Waves

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A Simple Transient Poiseuille-Based Approach to Mimic the Womersley Function and to Model Pulsatile Blood Flow

Dynamics ◽

10.3390/dynamics1010002 ◽

2021 ◽

Vol 1 (1) ◽

pp. 9-17

Author(s):

Andrea Natale Impiombato ◽

Giorgio La Civita ◽

Francesco Orlandi ◽

Flavia Schwarz Franceschini Zinani ◽

Luiz Alberto Oliveira Rocha ◽

...

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Blood Flow ◽

Boundary Conditions ◽

Quadratic Function ◽

Pulsatile Blood Flow ◽

Flow Through ◽

Simplified Analysis ◽

Function Models ◽

Flow Reversals

As it is known, the Womersley function models velocity as a function of radius and time. It has been widely used to simulate the pulsatile blood flow through circular ducts. In this context, the present study is focused on the introduction of a simple function as an approximation of the Womersley function in order to evaluate its accuracy. This approximation consists of a simple quadratic function, suitable to be implemented in most commercial and non-commercial computational fluid dynamics codes, without the aid of external mathematical libraries. The Womersley function and the new function have been implemented here as boundary conditions in OpenFOAM ESI software (v.1906). The discrepancy between the obtained results proved to be within 0.7%, which fully validates the calculation approach implemented here. This approach is valid when a simplified analysis of the system is pointed out, in which flow reversals are not contemplated.

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Unstable resonator and output-coupling design study for diffraction radiation generator near-mm sources

International Journal of Infrared and Millimeter Waves ◽

10.1007/bf01007425 ◽

1981 ◽

Vol 2 (3) ◽

pp. 605-627 ◽

Cited By ~ 1

Author(s):

Colin S. Willett

Keyword(s):

Output Coupling ◽

Diffraction Radiation ◽

Unstable Resonator ◽

Design Study ◽

Radiation Generator ◽

Diffraction Radiation Generator

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Oliver Heaviside: an accidental time traveller

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2017.0448 ◽

2018 ◽

Vol 376 (2134) ◽

pp. 20170448

Author(s):

Paul J. Nahin

Keyword(s):

Cherenkov Radiation ◽

Charged Particles ◽

Electromagnetic Theory ◽

Time Travel ◽

Characteristic Radiation ◽

Theme Issue ◽

The Past ◽

Faster Than Light

A little discussed aspect of Heaviside's work in electromagnetics concerned faster-than-light (FTL) charged particles, precursors to the hypothetical tachyon and his discovery that such motion should produce a characteristic radiation signature (now called Cherenkov radiation ). When Heaviside wrote, the time travel implications of FTL were not known (Einstein was still a teenager), and in this paper some speculations are offered on what Heaviside would have thought of FTL time travel, and of the associated (now classic) time travel paradoxes, including the possibility (or not) of sending information into the past. This article is part of the theme issue ‘Celebrating 125 years of Oliver Heaviside's ‘Electromagnetic Theory’’.

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