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Sensors ◽  
2022 ◽  
Vol 22 (2) ◽  
pp. 600
Author(s):  
Krzysztof Maniak ◽  
Remigiusz Mydlikowski

This paper analyses the function of an innovative integrated receiver for the measurement of electromagnetic field emissions. The autonomous receiver measures and registers the elevated emission levels of both components of the EM field originating from rocks subjected to increased mechanical stress. The receiver’s sensitivity of 60 µV/m, its dynamic range of 98 dB, and its impulse response of 0.23 V/µs were determined in laboratory conditions. Real EM field signals from hard coal samples subjected to crushing force were recorded using an autonomous receiver. The observed and recorded results confirm that the receiver operates in the full range of amplitudes of the EM field signal emitted from the rock. The results determine the band of characteristic signals for EM field emission from hard coal. The system created on the basis of autonomous EM receivers can support the existing seismic safety systems in real mine conditions by predicting the possibility of mine collapse hazards.



Author(s):  
Hiroki Sonoda ◽  
Takuji Miki ◽  
Makoto Nagata

Abstract Internet-of-things (IoT) devices are compact and low power. A voltage-controlled oscillator (VCO) based analog-to-digital converter (ADC) benefits from scaled CMOS transistors in representing analog signals in the time domain and therefore meets those demands. However, we find the potential drawback of VCO-based ADCs for the electromagnetic susceptibility (EMS) to radio-frequency (RF) disturbances that are essentially present in IoT environment. It is exhibited that the single and even differential designs of VCO-based ADC suffer from the EMS by RF disturbance, which behaves differently from the known common-mode noise rejection. A 28-nm CMOS 10-bit VCO-ADC prototype exhibit the sensitivity against RF signals in the widely used 2.4 GHz frequency band.



Sensors ◽  
2021 ◽  
Vol 22 (1) ◽  
pp. 240
Author(s):  
Michael Gerasimov ◽  
Egor Dyunin ◽  
Jacob Gerasimov ◽  
Johnathan Ciplis ◽  
Aharon Friedman

The construction of a transmission line (TL) for a wide tunable broad-spectrum THz radiation source is not a simple task. We present here a platform for the future use of designs of the TL through our homemade simulations. The TL is designed to be a component of the construction of an innovative accelerator at the Schlesinger Family Center for Compact Accelerators, Radiation Sources and Applications (FEL). We developed a three-dimensional space-frequency tool for the analysis of a radiation pulse. The total electromagnetic (EM) field on the edge of the source is represented in the frequency domain in terms of cavity eigenmodes. However, any pulse can be used regardless of its mathematical function, which is the key point of this work. The only requirement is the existence of the original pulse. This EM field is converted to geometric-optical ray representation through the Wigner transform at any desired resolution. Wigner’s representation allows us to describe the dynamics of field evolution in future propagation, which allows us to determine an initial design of the TL. Representation of the EM field by rays gives access to the ray tracing method and future processing, operating in the linear and non-linear regimes. This allows for fast work with graphics cards and parallel processing, providing great flexibility and serving as future preparation that enables us to apply advanced libraries such as machine learning. The platform is used to study the phase-amplitude and spectral characteristics of multimode radiation generation in a free-electron laser (FEL) operating in various operational parameters.



Sensors ◽  
2021 ◽  
Vol 22 (1) ◽  
pp. 38
Author(s):  
Tomasz Kowalski ◽  
Gian Piero Gibiino ◽  
Jarosław Szewiński ◽  
Krzysztof Czuba ◽  
Dominik Rybka ◽  
...  

The low-level radio frequency (LLRF) control system is one of the fundamental parts of a particle accelerator, ensuring the stability of the electro-magnetic (EM) field inside the resonant cavities. It leverages on the precise measurement of the field by in-phase/quadrature (IQ) detection of an RF probe signal from the cavities, usually performed using analogue downconversion. This approach requires a local oscillator (LO) and is subject to hardware non-idealities like mixer nonlinearity and long-term temperature drifts. In this work, we experimentally evaluate IQ detection by direct sampling for the LLRF system of the Polish free electron laser (PolFEL) now under development at the National Centre for Nuclear Research (NCBJ) in Poland. We study the impact of the sampling scheme and of the clock phase noise for a 1.3-GHz input sub-sampled by a 400-MSa/s analogue-to-digital converter (ADC), estimating amplitude and phase stability below 0.01% and nearly 0.01°, respectively. The results are in line with state-of-the-art implementations, and demonstrate the feasibility of direct sampling for GHz-range LLRF systems.



2021 ◽  
Vol 11 (40) ◽  
pp. 149-149
Author(s):  
Settimio Grimaldi

Background: Only recently has the critical importance of electromagnetic (EM) field interactions in biology and medicine been recognized. We review the phenomenon of resonance signaling, discussing how specific frequencies modulate cellular function to restore or maintain health. Evidence: Application of EM tuned signals represents more than merely a new tool in Information Medicine. It can also be viewed in the larger context of Electromagnetic Medicine, the all-encompassing view that elevates the electromagnetic over the biochemical. The discovery by Zhadin that ultrasmall magnetic intensities are biologically significant suggests that EM signaling is endogenous to cell regulation, and consequently that the remarkable effectiveness of EM resonance treatments reflects a fundamental aspect of biological systems. The concept that organisms contain mechanisms for generating biologically useful electric signals is not new, dating back to the 19th century discovery of currents of injury by Matteucci. The corresponding modern-day version is that ion cyclotron resonance magnetic field combinations help regulate biological information. Prospects: The next advance in medicine will be to discern and apply those electromagnetic signaling parameters acting to promote wellness, with decreasing reliance on marginal biochemical remediation and pharmaceuticals.



Author(s):  
Stanley A. Bruce

In this paper, we propose a simple generalization of axion-electrodynamics (AED) for the general case in which Dirac fermion fields and scalar/pseudoscalar axion-like fields are present in the local [Formula: see text]([Formula: see text])[Formula: see text] gauge-invariant Lagrangian of the system. Our primary goal (which is not explored here) is to understand and predict novel phenomena that have no counterpart in standard (pseudoscalar) AED. With this end in view, we discuss on very general grounds, possible processes in which a Dirac field is coupled to axionic fields via the electromagnetic (EM) field.



2021 ◽  
Vol 66 (6) ◽  
pp. 81-92
Author(s):  
O. Kurpeshev

The review analyzes the features of the interaction of electromagnetic (EM) energy with various tissues and the temperature distribution in model, experimental and clinical studies from emitters for external and intracavitary microwave hyperthermia (MWHT). The effect of MWHT on the antitumor efficacy of radiation (RT) and / or chemotherapy (CT), as well as toxic effects on normal tissues, was studied. Based on the literature data and our own experience, some approaches to the treatment of cancer patients have been identified. The general principles of the method, the design features of the applicators and their role in creating a hyperthermic regime in tumors of superficial and subsurface localization are also considered. The development of methods for thermometric control and supply of the EM field, allowing relatively uniform heating of tumors, as well as the determination of the minimum effective thermal doses, remains a priority area of research both in MW and other hyperthermia methods. Based on the literature data and our own experience, some approaches to the treatment of cancer patients have been identified.



2021 ◽  
Vol 64 (12) ◽  
pp. 95-103
Author(s):  
Haojian Jin ◽  
Jingxian Wang ◽  
Swarun Kumar ◽  
Jason Hong

Despite widespread popularity, today's microwave ovens are limited in their cooking capabilities, given that they heat food blindly, resulting in a nonuniform and unpredictable heating distribution. We present software-defined cooking (SDC), a low-cost closed-loop microwave oven system that aims to heat food in a software-defined thermal trajectory. SDC achieves this through a novel high-resolution heat sensing and actuation system that uses microwave-safe components to augment existing microwaves. SDC first senses the thermal gradient by using arrays of neon lamps that are charged by the electromagnetic (EM) field a microwave produces. SDC then modifies the EM-field strength to desired levels by accurately moving food on a programmable turntable toward sensed hot and cold spots. To create a more skewed arbitrary thermal pattern, SDC further introduces two types of programmable accessories: A microwave shield and a susceptor. We design and implement one experimental test bed by modifying a commercial off-the-shelf microwave oven. Our evaluation shows that SDC can programmatically create temperature deltas at a resolution of 21°C with a spatial resolution of 3 cm without the programmable accessories, and 183°C with them. We further demonstrate how an SDC-enabled microwave can be enlisted to perform unexpected cooking tasks: Cooking meat and fat in bacon discriminatively and heating milk uniformly.



Author(s):  
Stanley A. Bruce

We address the bound-state dynamics of relativistic spin-1/2 neutral particles (in this paper, Dirac neutrinos) with anomalous magnetic dipole moment in the presence of an electromagnetic (EM) field described by a generalized Dirac–Pauli equation. This equation of motion is derived including appropriate couplings between Lorentz scalar and pseudoscalar fields with the EM field in the Lagrangian of the system. Specifically, we exactly solve the bound-state problem of neutrinos in the presence of a homogeneous magnetic field in cylindrical coordinates. We comment on the relevance of this approach to study Dirac neutrino self-interactions.



2021 ◽  
Vol 1206 (1) ◽  
pp. 012011
Author(s):  
Neetirajsinh J Chhasatia ◽  
Jitendra P Chaudhari ◽  
Amit V Patel

Abstract This paper describes a simple, low loss, compact tuneable band pass filter based on ridge gap waveguide (RGW) technology for the Ku-band applications. This is achieved by keeping the height of the air gap in the gap guide structure equal to the thickness of the substrate or base of the structure. The resonant frequency and electromagnetic (EM) field distribution of the structure is investigated. This filter is designed by inserting the proposed ridge in the cut-off region of the gap waveguide. The frequency of tuning has been carried out using the slot created on ridge, which generates capacitive effect. Experimental results of the manufactured structure show an insertion loss of approximately 0.15 dB and a return loss of 16.38 dB over 4.5% relative bandwidth in Ku-band. The structure, put forwarded here, has been designed and optimized in the CST microwave studio environment and simulated results are validated by experimental results. The size of the structure is 64.65 mm × 64.65 mm × 7 mm.



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