scholarly journals Radiation power spectral distribution for two electrons moving in magnetic fields

2008 ◽  
Vol 8 (2) ◽  
pp. 70-74
Author(s):  
A. V. Konstantinovich ◽  
Keyword(s):  
Magnetic Fields ◽  
Spectral Distribution ◽  
Radiation Power ◽  
Power Spectral

scholarly journals Radiation Spectrum of Sequence of Electrons Moving in Spiral in Medium

2019 ◽  
Vol 20 (1) ◽  
pp. 5-12
Author(s):  
I.A. Konstantinovich ◽  
A.V. Konstantinovich
Keyword(s):  
Magnetic Fields ◽  
Spectral Distribution ◽  
Cherenkov Radiation ◽  
Radiation Spectrum ◽  
Radiation Power ◽  
Coherent Radiation ◽  
Transparent Medium ◽  
Interaction Method ◽  
Direct Numerical Method ◽  
Spectral Distributions

Integral expressions for spectral-angular and spectral distributions of the radiation power for the sequence of electrons moving in magnetic fields in isotropic transparent medium are investigated using the improved Lorentz`s self-interaction method. Special attention is given to the research of the fine structurre of the spectral distribution of the synchrotron-Cherenkov radiation of one, two, three and four point electrons moving along the spiral in medium. The effects of coherent radiation of harmonics and oscillations in spectrum of the synchrotron-Cherenkov radiation of two, three and four point electrons are established and investigated using the direct numerical method for calculation the function of spectral distributions of the radiation power.

Environmental considerations

2017 ◽  
Author(s):  
A. G. Wright
Keyword(s):  
Magnetic Fields ◽  
Collection Efficiency ◽  
Liquid Argon ◽  
Harsh Environments ◽  
Oil Well ◽  
High Permeability ◽  
Electric Field Gradients ◽  
Field Gradients ◽  
High Shock ◽  
Power Spectral

Magnetic fields, with a magnitude comparable with that of the earth (10−4 tesla), affect trajectories of electrons and hence gain and collection efficiency. The inclusion of a high-permeability shield usually offers sufficient protection. Photomultiplier (PMT) performance is affected by electric field gradients generated by the proximity of a metal housing. The design criteria of such housings are discussed. Strong magnetic fields of the order of a tesla require special devices. Operation in harsh environments such as those encountered in oil well logging requires performance at high temperature (200 °C) and in situations of high shock and vibration expressed in terms of power spectral density. Rugged PMTs can meet all these requirements. Applications at cryogenic temperatures, such as liquid argon, can also be met with special PMTs.

scholarly journals Primordial Magnetic Field Effects on the CMB and Large-Scale Structure

2010 ◽  
Vol 2010 ◽  
pp. 1-19 ◽  
Author(s):  
Dai G. Yamazaki ◽  
Kiyotomo Ichiki ◽  
Toshitaka Kajino ◽  
Grant J. Mathews
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Large Scale ◽  
Large Scale Structure ◽  
Big Bang ◽  
Scale Structure ◽  
Magnetic Field Effects ◽  
Power Spectral ◽  
Primordial Magnetic Field ◽  
The Big Bang

Magnetic fields are everywhere in nature, and they play an important role in every astronomical environment which involves the formation of plasma and currents. It is natural therefore to suppose that magnetic fields could be present in the turbulent high-temperature environment of the big bang. Such a primordial magnetic field (PMF) would be expected to manifest itself in the cosmic microwave background (CMB) temperature and polarization anisotropies, and also in the formation of large-scale structure. In this paper, we summarize the theoretical framework which we have developed to calculate the PMF power spectrum to high precision. Using this formulation, we summarize calculations of the effects of a PMF which take accurate quantitative account of the time evolution of the cutoff scale. We review the constructed numerical program, which is without approximation, and an improvement over the approach used in a number of previous works for studying the effect of the PMF on the cosmological perturbations. We demonstrate how the PMF is an important cosmological physical process on small scales. We also summarize the current constraints on the PMF amplitudeBλand the power spectral indexnBwhich have been deduced from the available CMB observational data by using our computational framework.

scholarly journals Methodology Proposal of ADHD Classification of Children Based on Cross Recurrence Plots

2021 ◽  
Author(s):  
Marco Aceves-Fernandez
Keyword(s):  
Machine Learning ◽  
Spectral Distribution ◽  
High Dimensional ◽  
Control Group ◽  
Machine Learning Method ◽  
Learning Method ◽  
Recurrence Plots ◽  
Eeg Signals ◽  
Power Spectral

Abstract Dealing with electroencephalogram signals (EEG) are often not easy. The lack of predicability and complexity of such non-stationary, noisy and high dimensional signals is challenging. Cross Recurrence Plots (CRP) have been used extensively to deal with detecting subtle changes in signals even when the noise is embedded in the signal. In this contribution, a total of 121 children performed visual attention experiments and a proposed methodology using CRP and a Welch Power Spectral Distribution have been used to classify then between those who have ADHD and the control group. Additional tools were presented to determine to which extent the proposed methodology is able to classify accurately and avoid misclassifications, thus demonstrating that this methodology is feasible to classify EEG signals from subjects with ADHD. Lastly, the results were compared with a baseline machine learning method to prove experimentally that this methodology is consistent and the results repeatable.

Investigating the Effect of Prestress Force on Cross-Tensioned Concrete Pavement Vibration

2020 ◽  
Vol 2674 (8) ◽  
pp. 875-886
Author(s):  
Hongduo Zhao ◽  
Mengyuan Zeng ◽  
Hui Chen ◽  
Jianming Ling ◽  
Difei Wu
Keyword(s):  
Spectral Distribution ◽  
Field Testing ◽  
Dominant Frequency ◽  
Fe Analysis ◽  
Concrete Pavement ◽  
Vibration Characteristics ◽  
Dynamic Responses ◽  
Power Spectral ◽  
Force Monitoring ◽  
The Time Domain

Prestress force loss is crucial to the structural performance of cross-tensioned concrete pavement (CTCP). Severe loss in prestress force will reduce the constricting-cracking capacity of the CTCP, resulting in damage with load and temperature applied. Vibration-based methods are commonly used in prestress force monitoring, but few relative studies are reported into CTCP and the relationship between prestress force and CTCP vibration is still unclear. The purpose of this paper is to investigate the effect of prestress force on CTCP vibration. The vibration characteristics of CTCP subjected to different prestress forces were studied through field testing and finite element (FE) analysis. Impulse load was applied as excitation at the anchorage zone and dynamic responses were measured in the time domain. A signal processing method was employed to obtain short-time power spectral from original vibration signals, which was utilized to extract vibration characteristics in time and frequency. As shown in both the field testing and the FE analysis, the prestress force has a more significant effect on frequency spectral distribution, rather than the dominant frequency. Integrated frequency is proved to be a reliable index for describing frequency spectral distribution and has a good correlation with prestress force, which suggests it can be used to reflect the change in prestress force. Overall, these findings indicate that vibration testing has potential in prestress force monitoring in CTCP, though the practicality of this method requires further demonstration.

scholarly journals Influence of the near-surface regions of the space charge in semiconductor crystals on defect transformation stimulated by action of magnetic fields

2021 ◽  
Vol 24 (1) ◽  
pp. 43-47
Author(s):  
G.V. Milenin ◽  
◽  
R.A. Redko ◽  
◽  
Keyword(s):  
Magnetic Fields ◽  
Electromagnetic Radiation ◽  
Space Charge ◽  
Radiation Power ◽  
Charge Carriers ◽  
Induction Vector ◽  
Near Surface ◽  
Semiconductor Crystals

The mechanisms of electromagnetic radiation in the near-surface regions of semiconductors depleted of the majority charge carriers under action of magnetic fields, the induction vector of which is parallel to the surface of the crystal, have been analyzed. The relationships for estimating the radiation power of space charge regions have been derived.

scholarly journals Brightness power spectral distribution and waves in Jupiter's upper cloud and hazes

Icarus ◽  
2009 ◽  
Vol 202 (1) ◽  
pp. 181-196 ◽  
Author(s):  
N. Barrado-Izagirre ◽  
S. Pérez-Hoyos ◽  
A. Sánchez-Lavega
Keyword(s):  
Spectral Distribution ◽  
Power Spectral
Sign in / Sign up

Export Citation Format

Share Document