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Purpose - The purpose of this paper is to compare the properties of simplified physical and corresponding numerical human body models (phantoms) and verify their applicability to path loss modeling in narrowband and ultra-wideband on-body wireless body area networks (WBANs). One of the models has been proposed by the authors. Design/methodology/approach - Two simplified numerical and two physical phantoms for body area network on-body channel computer simulation and field measurement results are presented and compared. Findings - Computer simulations and measurements which were carried out for the proposed simplified six-cylinder model with various antenna locations lead to the general conclusion that the proposed phantom can be successfully used for experimental investigation and testing of on-body WBANs both in ISM and UWB IEEE 802.15.6 frequency bands. Research limitations/implications - Usage of the proposed phantoms for the simulation/measurement of the specific absorption rate and for off-body channels are not within the scope of this paper. Practical implications - The proposed simplified phantom can be easily made with a low cost in other laboratories and be used both for research and development of WBAN technologies. The model is most suitable for wearable antenna radiation pattern simulation and measurement. Social implications - Presented results facilitate applications of WBANs in medicine and health monitoring. Originality/value - A new six-cylinder phantom has been proposed. The proposed simplified phantom can be easily made with a low cost in other laboratories and be used both for research and development of WBAN technologies. [ABSTRACT FROM AUTHOR]

Purpose In electrochemotherapy, flexible electrodes, composed by an array of needles, are applied to human tissues to treat large surface tumors. The positioning of the needles in the tissue depends on the surface curvature. The parallel needle case is preferred, as their relative inclinations strongly affect the actual distribution of electric field. Nevertheless, in some case, small inclinations are unavoidable. The purpose of this paper is to study the electric field distribution for non-parallel needles.Design/methodology/approach The effect of electrode position is evaluated systematically by means of numerical models and experiments on phantoms for two different angles (5° and 30°) and compared with the case of parallel needles. Potato model was used as phantom, as this tissue becomes dark after few hours from electroporation. The electroporation degree was gauged from the color changings on the potatoes.Findings The distribution of electric field in different needle configuration is found by means of finite element analysis (FEA) and experiments on potatoes. The electric field level of inclined needles was compared with parallel needle case. In particular, the electric field distribution in the case of inclined needles could be very different with respect to the one in the case of parallel needles. The degree of enhancement for different inclinations is visualized by potato color intensity. The FEA suggested that the needle parallelism has to be maintained as possible as if the tips are closer to each other, the electric field intensity could be different with respect to the one in the case of parallel needles.Originality/value This paper analyzes the effect of inclined electrodes considering also the non-linearity of tissues. [ABSTRACT FROM AUTHOR]

An excerpt from the paper "Tissue-Mimicking Phantoms for Photoacoustic and Ultrasonic Imaging," is presented.

The article previews the Borealis collection of Type II vinyl wallcovering from Wolf-Gordon.

In some models dark energy is described by phantom scalar fields (scalar fields with the "wrong" sign of the kinetic term in the Lagrangian). In the current paper we study the effect of phantom scalar field and/or phantom electromagnetic field on gravitational lensing by black holes in the strong deflection regime. The black-hole solutions that we have studied have been obtained in the frame of the Einstein-(anti-)Maxwell-(anti)dilaton theory. The numerical analysis shows a considerable effect of the phantom scalar and electromagnetic fields on the angular position, brightness, and separation of the relativistic images. [ABSTRACT FROM AUTHOR]

Abstract: This paper proposes a numerical technique, based on the boundary element method, for the reconstruction of the specific absorption rate in 3-D human phantoms. The method intends to relate electric and magnetic field measurements on the surfaces of a virtual box surrounding the considered phantom with the SAR values within the body. After a description of the adopted boundary element approach, an analysis of the influence on the SAR reconstruction accuracy of several parameters, such as size and shape of the virtual box, or position and number of the measurement points, is presented. The effect of the field source and supply frequency is also investigated. Finally, an extension of the approach to non-homogeneous phantoms is discussed. [ABSTRACT FROM AUTHOR]

Purpose - The classical f-a formulations for numerical dosimetry of currents induced by extremely low frequency magnetic fields requires that the source field is provided through a vector potential. The purpose of this paper is to present a new formulation t-b which directly takes the flux density as source term. Design/methodology/approach - This formulation is implemented through finite element and validated by comparison with analytical solutions. The results obtained by both formulations are compared in the case of an anatomical computational phantom exposed to a vertical uniform field. Findings - A good agreement between the t-b formulation and both numerical and analytical computations was found. Originality/value - This new formulation seems to be more accurate than the f-a formulation, and is more suited for situations where the magnetic field is known from experimental measurements, as there is no need for a magnetic vector potential. [ABSTRACT FROM AUTHOR]

The article discusses the growing use of simulation in the biomedical sector in 2022. Topics covered include computational modeling to support medical devices in line with the U.S. Food and Drug Administration's (FDA) initiatives, and such technologies as a novel heat therapy for brain cancer treatment, a human-heart model for cardiovascular analysis and treatments, and computed tomography (CT) scanners for diagnostic products. Also noted are hand-held ultrasound body-imaging devices.