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This study introduces an approach to predicting cardiovascular diseases (CVDs) by leveraging neural networks and evaluates its performance against the widely recognized SCORE2 risk assessment tool. Given the significant global health impact of CVDs, our research aims to assess the effectiveness of deep learning‐based models compared with traditional methods. Our methodology involves developing and deploying a neural network model capable of learning intricate patterns and relationships from a comprehensive dataset. Leveraging a large population cohort with extended follow‐up enables precise and long‐term risk estimation. We utilize the T‐paired test to compare risk predictions between our neural network model and the SCORE2 tool. Our results indicate a notable accuracy of 0.77 for our neural network‐based model in predicting CVDs, with the T‐paired test revealing no significant variations in risk levels between the two methods. These findings underscore the effectiveness of neural networks as a robust tool for CVD risk prediction and advocate for further exploration and integration of these technologies to enhance cardiovascular risk assessment, thereby advancing predictive modeling in healthcare. [ABSTRACT FROM AUTHOR]

This paper describes the design of a hybrid coupler with a continuously variable output phase difference. This is achieved by using reconfigurable transmission lines with electrically tunable lengths controlled by two biasing voltages through varactor diodes placed across the coupler branches. The design of the coupler is based on the quadrature hybrid structure for the case where the output phase difference is 90° and on the asymmetric structure for the other cases. The proposed coupler can achieve a tunable output phase difference from 52° to 128°, while keeping a coupling coefficient of −3 dB (± 0.5 dB) over the entire desired frequency band. To validate the simulated results, a prototype working at 3.5 GHz was fabricated and tested. The measurement results show good correspondence with the simulation results, especially when the output phase difference is 90°, while a phase mismatch of less than 7° was observed for the other cases. The presented coupler would be a great asset for antenna feeding arrays, especially the Butler matrix. [ABSTRACT FROM AUTHOR]

Artificial intelligence has had an impact on a variety of fields, including medicine and, most importantly, cardiovascular diseases. Indeed, early diagnosis of many disorders is a serious medical issue. In this article, we will compare various machine learning algorithms in order to select the optimal one for diagnosing people who might suffer from heart disease based on a variety of clinical data from patients. The effort in this article is focused on studying the dataset using data mining algorithms, and also explaining the used machine learning algorithms in predicting heart disease, in order to assist future researchers in getting the most out of these skills.

Antipodal Vivaldi antennas hold significant importance in medical applications, particularly in the field of microwave imaging, due to their wideband characteristics and efficient radiation properties. These antennas have shown promising results, enabling precise tumor localization and characterization in breast cancer detection, thus facilitating early diagnosis and improving patient outcomes (vers la conclusion). This paper presents the development of a prototype antipodal antenna through a meticulous process that involved using an electromagnetic solver that utilizes the Finite Element Method (FEM) for conceptualization and subsequent realization of the proposed antenna. Rigorous testing in our laboratory has demonstrated auspicious and concrete results, showcasing the antenna's exceptional performance in terms of radiation patterns and efficacy in the Ultra-Wide Band (UWB) frequency region. Furthermore, we found a strong correlation between the simulated and measured values of the reflection coefficients (S11), validating the accuracy and reliability of our design approach. These findings mark substantial progress in our pursuit of developing a low-cost imaging system for early breast cancer detection. [ABSTRACT FROM AUTHOR]

This W presents a new technique of Dielectric Characterization of composites building materials. This technique is based on the modeling of an open coaxial cell with a mathematical formulation that links the admittances of the filled and empty cell to the complex permittivity ε* of materials characterization. We applied this technique to the dielectric characterization of some building materials powder in the frequency band (100MHz-4GHz). We also characterize some composite materials (sand- brick, cement- sand, and cement-brick) depending on the volume fraction for Mobile Phone Frequencies. We made a comparison with the laws of mixtures to identify the most appropriate law to render the dielectric behavior of these materials.

The application of the Nicolson-Ross and Weir (NRW) technique is based on the mesurement of the scattering parameters (S-parameters), and calculation simultaneously of the real and the imaginary parts of the relative complex permittivity εr * and the relative complex permeability μr * of the Lanthanum Iron Garnet loaded PVDF (polyvinylidene fluoride) polymer nano-composites. The complex reflection S11 and complex transmission S21 coefficients were calculated by transmission/reflection measurement method. The 13%-LIG/PVDF nano-composite is placed in rectangular waveguide at X-band frequencies. The average values of the real and imaginary parts of the relative complex permittivity and relative complex permeability of 13%-LIG/PVDF in X-band frequencies are (4.34 - j0.09) and (1.27 - j0.15) respectively. The valeus obtained in this work are in good agreement with the results obtained in the literature. [ABSTRACT FROM AUTHOR]

A microwave technology is the most safety and accuracy method for breast cancer detection in the early stages. This paper proposes a novel method for detecting and locating a tumor by measuring the energy absorbed in normal tissue and malignant tissue. This method is based on the conception of an UWB biomedical system, especially an UWB microstrip antenna, which plays an important part in determining the system performances. In this contribution we proved the feasibility of detecting small breast tumors using SAR technique with high precision and efficiency. [ABSTRACT FROM AUTHOR]

This paper presents an original elliptical microstrip patch antenna is proposed for Ku/K band satellite applications. The proposed antenna has a simple structure, small size with dimensions of about 10×12×1.58 mm3. The antenna has been designed and simulated on an FR4 substrate with dielectric constant 4.4 and thickness of 1.58 mm. The design is simulated by two different electromagnetic solvers. The results from the measured data show that the antenna has two resonant frequencies that define 2 bandwidths, defined by a return loss of less than -10 dB, and are: (14.44 GHz, 829 MHz) and (21.05 GHz, 5126 MHz),with the gain 5.59 dB and 5.048 dB respectively. The proposed antenna can be used in many applications such as in satellite, and wireless communications. [ABSTRACT FROM AUTHOR]

The patch antenna miniaturization with less human health impacts was the aim of recent studies. This paper proposes a design of small sized, low profile quadri-band patch antenna operating at four frequency bands of 900MHz, 1800MHz, 2100MHz and 2600MHz. The dosimetry and temperature distribution studies were achieved, which show that the antenna performance was good and results obtained were optimum. The SAR and the temperature rise are obtained with various simulations results on Ansoft HFSS software that show the impact of the mobile-head distance and exposure time on the electromagnetic waves (EMWs) absorption by tissues protecting the brain of radiation. [ABSTRACT FROM AUTHOR]

In this paper, we propose the design of and provide an analysis of, a rectangular patch antenna and its integration in a 4 element linear array. A T form power divider feeds in parallel the array elements through microstrip lines. The basic antenna has a simple structure, with dimensions of about 16×18×1.6 mm3, leading to a good bandwidth. In addition, the patch element characteristics, such as the reflection coefficient and the voltage standing wave ratio (VSWR), are improved by the insertion of a slot in the structure. The main objective of the 4 element array structure is the enhancement of the gain, which is enhanced up to 12.6 dBi. A prototype of the antenna is fabricated and tested with network analyzer. The proposed antenna has 4 resonant frequencies that define 4 bandwidths, defined by a return loss of less than -10 dB, and are: (7.62 GHz, 1250 MHz), (9.20 GHz, 330 MHz), (11.07 GHz, 940 MHz) and (15.02 GHz, 920 MHz), respectively. The simple configuration of this profile permits an easy and lowexpense fabrication process, with usability in many applications such as in radar, satellite, and wireless communications. [ABSTRACT FROM AUTHOR]

This paper presents a small square patch antenna for UWB communications. The designed antenna with dimensions of 14x19mm² was fabricated on FR4 epoxy substrate dielectric with permittivity of 4.4. In this structure there is a square patch which consists of a partial ground plane and that is fed by a 50 microstrip line. This have been investigated numerically and experimentally in detail. As will be seen, the operation bandwidth of the fabricated antenna is from 3.82 to 11.72 GHz for S11≤-10dB, with stable and bi-directional radiation pattern. The gain is good and has a peak value of 4.55dBi. In terms of bandwidth, comparable results between the simulation and measurement results clearly shows the validity of the proposed structure. The simulation of this antenna has been performed by using Ansoft High Frequency Structure Simulator (HFSS) and Computer Simulation Technology- Microwave Studio (CST). [ABSTRACT FROM AUTHOR]

ABSTRACT In this article, a miniaturized rectangular printed antenna that meets the ultrawideband (UWB) characteristics in terms of bandwidth and reflection coefficient is proposed. The designed antenna with dimension of 25×16 mm2 (L × W) was fabricated on FR-4 epoxy dielectric with relative permittivity of 4.4. SMA female connector is used for feeding with characteristic impedance of 50 Ω. The antenna exhibits good UWB characteristics and has the capability of operating between 3.92 to 11.32 GHz. The proposed antenna has omnidirectional radiation pattern on most of the operating band. The measured reflection coefficient of the proposed antenna is compared with the simulated one; good agreement is observed. Also, radiation pattern and gain of the antenna are presented. All simulations are carried out using the EM commercial simulators, HFSS, and CST. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:460-463, 2015 [ABSTRACT FROM AUTHOR]

This paper presents a simple waveguide measurement technique to determine the complex permittivity and complex permeability of a dielectric material. The dielectric sample is loaded in the transmission line rectangular waveguide WR90. The S-parameters of the waveguide are measured by Network analyzer and calculated as a function of the complex permittivity and complex permeability using theory of transmissions lines. Using the MatLab Optimization Tools, a simple MatLab scripts is written to look for complex permittivity and complex permeability of a dielectric material so as to match the measured and calculated values of S-parameters. The complex permittivity and complex permeability of Teflon, Nylon and Delrin at the X-band frequencies are then determined. [ABSTRACT FROM AUTHOR]

In this paper, a wide-band and high-gain microstrip antenna with mullti-layer microstrip patch and an aperture-coupled feeding is proposed. The antenna has a condensed structure where the dimension is about 8.5mm by 7.5mm by 4.662mm leading to good bandwidths covering 8.05 GHz to 12.01 GHz (39.48%), and the gain is up to 5.23dB. The low expenses of this profile and its simple configuration allows for an its easy fabrication, with appropriation with wireless and satellite communication. [ABSTRACT FROM AUTHOR]

A miniaturized microstrip antenna that meets the requirements of UWB systems in terms of bandwidth and reflection coefficient is presented in this paper. This antenna is designed for a system to detect malignant tumors by microwave imaging. We use certain miniaturization techniques of slots and partial ground plane for expansion of bandwidth in order to achieve our intention. The proposed antenna exhibits good UWB characteristics and has the capability of operating from 2.85GHz to 13.21GHz. The antenna has an ordinary rectangular radiating patch, therefore displays a good omnidirectional radiation pattern. The detailed design and the results are shown and discussed in this paper. [ABSTRACT FROM AUTHOR]

In this paper, a comparative study of dipole and patch antennas commonly used in portable telephones is investigated. The two models antennas are considered working at 900, 1800 and 2450 MHz bands. Thus, we have included different distances between the mobile phone and the human head model. This study shows the effects of electromagnetic waves on the human head model. The objective is to evaluate the SAR in simulation anatomic based model of the human head for different antenna-head distances and in many frequencies. All numerical simulations results are performed using Ansoft HFSS software. [ABSTRACT FROM AUTHOR]