Introduction In recent years measurement of permittivity signal has been increasingly used for online biomass monitoring of cell cultures. Breweries use it as an established method for fermenter inoculation and bioprocess control for instance [1]. In the case of animal cell cultures the correlation between permittivity and viable cell densities determined offline varies along cultivation time. ...

It is crucial to know the permittivity of dielectric materials used in radio frequency (RF) components and devices because their operation loss characteristics are significantly affected by permittivity. In this study, we propose a characterization technique based on deep neural network (DNN). The latter was trained using data obtained from full-wave electromagnetic simulation software. With DN...

A porous material was considered as a platform for optical sensing. It was envisaged that the porous material was infiltrated by a fluid that contains an agent to be sensed. Changes in the optical properties of the infiltrated porous material provide the basis for detection of the agent to be sensed. Using a homogenization approach based on the Bruggeman formalism, wherein the infiltrated porou...

In this paper, we study a Dielectric Resonator Antenna of cylindrical shape with circular polarization for applications in the C band. The proposed antenna is composed of two different layers. The first is Polyflon Polyguide with relative permittivity εr1 = 2.32 and a loss tangent tanδ = 0.002 as a lower layer. The second is Rogers RO3010 with relative permittivity εr2 = 10.2 and a loss tangent...

Measurements with different techniques point to a strong affinity of hydroxide ions for interfaces between water and hydrophobes, but some spectroscopic experiments do not detect excess hydroxide at the interface, while others do. Hydroxide ions are unusual in that they reduce the relative permittivity of an electrolyte solution more than other monovalent, monatomic ions. This implies that they...

An electromagnetic logging technique based on borehole radar is introduced in this paper. The tool consists of one transmitter and two receivers, which can be used to cancel the effect of the antenna characteristics by taking the ratio of two receiver signals. Since receiver signals measured in the time domain can be converted into the frequency domain by Fourier transformation, the amplitude r...

The insulating performance of oil is vulnerable to particles especially the conductive particles. This paper investigated the influence of copper particles of micrometer size on the breakdown strength and frequency-dependent properties of vegetable oil. The AC breakdown voltage of contaminated vegetable oil with copper particles of different numbers (ranging from 103 to 106) was measured. The f...

Numerical simulation of passive microwave remote sensing of ocean surfaces has a strict requirement of accuracy. This is because the key output of the simulations is the difference of brightness temperature between a rough surface and a flat surface. Since the difference can be as small as 0.5 K, it is important to simulate the scattering and emission accurately. In this paper, we perform accur...

Nanoparticles are generally anti-lipophilic and have a tendency to aggregate when they embedded in nanofluids. Thus, surfactants major role achieving long term dispersion stability of nanofluids through surface modification nanoparticles. However, the surfactant changes structure interfacial zone around nanoparticles can crucial impact on dielectric properties Accordingly, this paper aims clari...