model-based microwave imaging system

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Breast Tumor Detection System Based on a Compact UWB Antenna Design

Breast Tumor Detection System Based on a Compact UWB Antenna Design

In order to verify the validation of any imaging technique, a model representing the main tissues of the object under study is required. The principle of microwave imaging for breast cancer detection is based on the large contrast of the dielectric constant and conductivity between the malignant tumor and other breast tissues [8, 9]. In fact, a UWB microwave pulse is radiated by the antenna into the breast penetrating the skin and traveling through the breast to interact with the malignant and other breast tissues. The reflections occurring on the surface of these tissues are due to different characteristics of microwave absorption, reflection and transmission. As the breast tissues appear as lossy dispersive material to the microwave propagation, it is necessary to take the dispersive effect into account to approach the real electrical properties of the breast model. Their behaviour, to variation of frequency, is most likely to be governed by single-pole Debye model, expressed as follows:
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Holographic Microwave Imaging Array for Brain Stroke Detection

Holographic Microwave Imaging Array for Brain Stroke Detection

This paper proposes a new holographic microwave imaging array (HMIA) technique for brain stroke detection. This approach is based on holographic microwave and aperture synthesis imaging techniques. The system is designed for operation at a single frequency of 2.5 GHz. A realistic three dimensional (3D) head model that contains skin, fat, skull, cerebrospinal fluid (CSF), grey matter, white matter and ischemic or hemorrhagic stroke area is developed using MATLAB to demonstrate the proposed HMIA imaging algorithm. A matching solution medium is used between the antennas and the head model. The study is conducted using HMIA computer simulations and 3D head model with- stroke.The simulation results showed that small stroke area (5 mm in diameter) could be successfully detected with the HMIA approach.
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Implementation Of The Novel MSP Dielectric Antenna Design On Effective Prediction Of Breast Cancer

Implementation Of The Novel MSP Dielectric Antenna Design On Effective Prediction Of Breast Cancer

Elham et al (2019) [1] proposed about the two time-reversal (TR) based algorithms performances which are decomposition of the time reversal operator and time-reversal multiple signal classification for the detection of breast cancer over UWB microwave image which assess their application. Wang et al (2018) [2] proposed about the microwave antenna of wideband for the purpose of health microwave breast imaging. A number of simulations were conducted for the validation of proposed antenna scheme. The outcomes reveal that the presented antenna scheme has some potential for the microwave imaging system application for the recognition of breast lesions. Ren et al (2018) [3] proposed about the FRET strategy with F19 fluorescence proteins for the effective identification of the tumor. Akinci et al (2019) [4] proposed about the use of the dissimilarity agents that increases the dielectric properties of malignant tissue in a selective manner. Conversely, both field measurements that were multi-static will be collected after and before the contrast agent administration. Afterwards, the Green’s function of the breast that were homogeneous will be predictable through the back- propagation of the dielectric magnetic field and after that phantoms of breast could be obtained in the form of the 3D measurements. Akki et al (2019) [5] proposed about the modeling of Multi-physics to learn the cold stress and tissue compression influence on improving the detection of breast tumor with the use of microwave radiometry. Avsar et al (2019) [6] anticipated the breast model that were double layered with a globular swelling and were located in the layer of fibro- glandular was made with the utilization of software CST microwave studio. This will be embedded in the canola oil for declining the signals that were distorted among the receiving
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Data Analysis Techniques for Microwave Imaging Reflectometry

Data Analysis Techniques for Microwave Imaging Reflectometry

Present MIR system on LHD has three antennas that separate in the toroidal and poloidal directions. A probe beam with frequencies of 53, 66, and 69 GHz in either the O- or the X-mode illuminates the plasma [1, 2]. The il- luminating beam is parallel to the 20 cm diameter in the plasma, which is limited by the window of LHD. The re- ceiving focus spot size in the plasma is about 3-4 cm in diameter. The beam separation is about 8.4-10 cm in the toroidal direction and 10-12 cm in the poloidal direction on the cuto ff surface. Therefore, there is no overlapping between neighboring channels. The injection paths of the beams are optimized, which is in agreement with the ray
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Compact Wideband Antenna for Microwave Imaging of Brain

Compact Wideband Antenna for Microwave Imaging of Brain

The design of a compact wideband tapered slot antenna immersed in a coupling liquid for the use in a microwave-based brain imaging is presented. The coupling liquid is designed properly to improve the matching between the antenna and the brain tissues using a mixture of water, grape seed oil and polysorbate 80(Tween-80). To miniaturize the antenna, corrugations are introduced in outer edges of both the radiator and the ground plane. To protect the antenna from ill effects, such as corrosion of the conductive layers by the coupling liquid, the antenna is covered by a dielectric sheet. The simulated and measured return loss of the antenna tested with and without a head phantom have shown that the antenna covers the band from 1 GHz to 4 GHz with better than 10 dB return loss across the desired band.
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Microwave Radiometer Analysis for Imaging and Vehicular Systems

Microwave Radiometer Analysis for Imaging and Vehicular Systems

always softer types of surface compared to the vegetated lands. J.L. Sánchez,ainsi que al.(2013)[3] proposed a lot of the meteorological phenomena developing from meso-γ require findings enough close in concert around time and space. Your multichannel micro wave radiometer (MMWR) offers constant temperatures and wetness profiles. Many of us illustrate the solution to account disposition static correction that tremendously enhances vertical temperatures (T) and mineral water vapor denseness (δwv) account accuracy. We compared MMWR temperatures (TRD) and wetness (δwvRD) users during winter within the Sierra associated with Guadarrama (Madrid) from 1150 meters altitude together with thousands of radiosonde temperatures (TRW) and wetness soundings at a launch site from 610 meters altitude and 50 km distance. Even with somewhat significant vertical and horizontal separating involving the 2 main web sites, looking distinctions above the limit part tend to be comparable to observation problem normally allotted to radiosonde soundings when consumed in to math weather models. Wolfgang Krüll,ainsi que al.(2012)[4] proved your scientific study “Intercontinental Woodlands Flame Fighting” (iWBB) has been loaned from the Reverend with regard to Economic Extramarital affairs and Strength of the Talk about associated with North Rhine- Westphalia, Germany. Several grouped corporations, investigation organizations and schools have been group to cultivate an incorporated, nonetheless flip-up system. An internal approach for earlier woodland fire detection and reduction will depend on a respectable collaboration of detection programs according to a wild fire danger, how big the the spot and man occurrence connected to a respectable logistical facilities, education through simulation, and impressive extinguishing technology. Seeing that regarding wildfires significant spots should
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A Comparative Study for Breast Cancer Detection by Neural Approach for Different Configurations of the Microwave Imaging System

A Comparative Study for Breast Cancer Detection by Neural Approach for Different Configurations of the Microwave Imaging System

Breast cancer is one of the most common cancers for women. For this, detection and early intervention are one of the most important factors in improving survival rates and quality of life of people with this type of cancer, since this is the time when treatment is most effective [1]. X-ray mammography is one of the most widely used imaging methods for early detection of breast cancer. However, despite significant progress in the improvement of the mammographic technique, persistent limitations lead to high rates of false negatives [2] and high rates of false positives [3] particularly in premenopausal women where increased breast density can obscure non-palpable lesions [4]. These false-positive diagnoses result in unnecessary biopsies, causing considerable distress to the patient and unnecessary financial burden on the health service. These limitations motivate the need of other methods that can overcome such limitations in a cost-effective manner.
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An active microwave sensor for near field imaging

An active microwave sensor for near field imaging

Roger W Clarke (M’06) is a senior lecturer in the Electrical Engineering and Computer Science in the School of Engineering and Informatics at the University of Bradford. Since joining the University in 1987, he has worked on a wide variety of projects in the area of Radio Frequency design within the Antennas, Propagations and RF design research group, Bradford University, UK. Recently, he has worked on multiple-antenna technologies, General electronics for re-configurable antennas, antenna design, battery technology and electric vehicles. His main research interests are Radio frequency, electromagnetic computational techniques, compact sensors design, advanced materials engineering, MIMO systems, energy- efficient and reconfigurable transceivers, beam steering, radio reconfigurable system design and sensors for breast cancer applications. Dr Clarke is member of the Institution of Engineering and Technology and Fellow of Higher Education Academy and a Chartered Engineer.
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Microwave Imaging Reflectometry Experiment in TPE-RX

Microwave Imaging Reflectometry Experiment in TPE-RX

In this case, the 2-D Yagi-Uda antenna array is em- ployed. Figure 5 (f) shows MIR channel numbers at the detector position schematically. Here, subscripts p and t denote the poloidal and toroidal directions, respectively. Since the imaging optics make vertical inverted images, the p direction corresponds to the positive sign in the plasma, and the t direction corresponds to the clockwise direction in the top view. As waveforms are similar to those in other channels, the 2-D receiver works well. Examples of MIR signals from this plasma are shown in Figs. 6 (a)-(b). Fig- ure 6 (a) shows fluctuations in the standard RFP plasma with Θ = 1.5 at t = 0.019 s. Figure 6 (b) shows fluctua- tions in the high- Θ plasma with Θ = 1 . 7 at t = 0 . 029 s. In both cases, the MIR signal contains many short-period bursts of waves with di ff erent frequencies. The signal con- tains high-frequency components in the case of the high-Θ
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A Novel Time Reversal Based Microwave Imaging System

A Novel Time Reversal Based Microwave Imaging System

A new prototype for an active microwave imaging system is presented in this paper. The key feature of the system is the utilization of a tunable reflectarray antenna to scan the region of interest (ROI). The collected scattered field is then conveniently used in a time reversal based algorithm to detect scatterers. This is an alternative to conventional microwave imaging systems with significant advantages. A traditional tomographic setup needs an array of costly transceivers to be placed all around the object [6–11]. This requires complicated circuitry and results in a high production cost of the system. The reflectarray paired with a single source greatly alleviates both of these issues. In addition, unlike conventional setups, this system is not constrained by the dimensions of the object. Therefore the inspection of large objects such as extended laminate structures and composite airplane wings becomes possible. Moreover, our system is scalable and has the potential for medical applications such as breast cancer detection. Not only can the system detect a tumor, the beam shaping capability of the reflectarray allows for the formation of pencil-shaped beams for therapy purposes. This work was inspired by [12, 13], where a system employing a deformable mirror for generating projections was investigated using a theoretical framework. This paper presents the implementation using the reflectarray instead of a mechanically conformable mirror. Details on the design of the proposed system and experimental results attained using a prototype are presented in this work.
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Live Imaging of Host Parasite Interactions in a Zebrafish Infection Model Reveals Cryptococcal Determinants of Virulence and Central Nervous System Invasion

Live Imaging of Host Parasite Interactions in a Zebrafish Infection Model Reveals Cryptococcal Determinants of Virulence and Central Nervous System Invasion

minants, we infected zebrafish larvae with several C. neoformans mutants chosen for their description as virulence or fitness factors in mice to verify that the zebrafish infection model recapitulates findings from standard vertebrate models. (i) Capsule formation is a characterizing feature of cryptococcus that becomes enlarged within specific sites within the host and is essential for human disease production. The capsule surrounds the cell wall and is a critical virulence factor with a multitude of effects in the host, including preventing phagocytosis by macrophages (16). cap64 is a key capsule formation gene: deletion of this gene, cap64⌬, has been reported to compromise capsule formation and cryptococcal virulence in mammals (20). (ii) PLB1 encodes a secreted phospho- lipase B that may function in multiple processes that contribute to disease within the host, including survival in macrophages and/or possible nutrient acquisition through breakdown of host phos- pholipids of the phagosome, and the plbl⌬ deletion mutant is avirulent in the murine system (21, 22). (iii) The ability to adapt to growth at 37°C is a common attribute of all human pathogens. The trehalose pathway is critical for the ability of this yeast to grow at 37°C (23, 24). The examined tps1⌬ strain lacks the ability to produce trehalose and is unable to survive at high temperatures in vitro and in vivo (23, 25). In vivo, the tps1⌬ strain is rapidly cleared from infected mice. However, the tps1 ⌬ mutant is also avirulent in the C. elegans model system (25), suggesting roles beyond adapta- tion to elevated temperatures since C. elegans is maintained at room temperature. (iv) URE1 encodes a urease enzyme that has
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Hyperspectral Imaging System Model Implementation and Analysis

Hyperspectral Imaging System Model Implementation and Analysis

Different applications have different algorithms, and another difference in system modeling lies in the processing of the data. There were different data processing algorithms implemented for different applications. For sup- porting relatively small target detection and high sensor altitude imaging, [15] extended the application into subpixel target detection, based on a subpixel object model using the subpixel fraction to define the fractional area of the pixel occupied by the object within direct sight of the sensor. In the subpixel target detection scenario, several pairs of parameter trade-offs, and also in different combination of backgrounds were discussed and analyzed to better understanding the detection performance. [14] used the system model to pre- dict unmixing performance, which included a different post-processing method applied to the data. Then the data observed from real world was shown to compare well with the predicted result, which validated another application of the FASSP model.
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Application of Group Theory for Computation Reduction in Microwave Imaging of Human Breast Model at 500 MHz

Application of Group Theory for Computation Reduction in Microwave Imaging of Human Breast Model at 500 MHz

Breast cancer detection research using microwave imaging is growing rapidly due to non-ionizing nature of microwave radiation. However, there are several pending research challenges in this research area. Microwave signal is transmitted by antenna arrays surrounding human breast. This signal then interacts with the breast tissues. According to dielectric profile of breast tissues, signal is scattered and received at receivers surrounding human breast. Now, based on this received signal dielectric profile of breast tissues is reconstructed in inverse problem. Two breast models are used in this paper. First model is used for explanation of group theory concepts. Second model is used in simulation. Forward problem is solved by using moment-method formulation of electric field integral equation [1–5]. Group theory is applied on matrices to exploit symmetry. Now, Inverse scattering problem is formulated in the presence of noise. This formulated problem is solved by using Levenberg-Marquardt algorithm. An overview of previous work is given below which form base for this research paper. Computation reduction using group theory in human breast model is reported in [1]. Phase unwrapping and log-phase formulation is used to implement 3-D microwave imaging of breast cancer in [2]. Method of moments based electric field calculation inside biological body is shown in detail [3]. Matrix formulation of electromagnetic problem is given using method of moments in [4]. Microwave imaging of human chest 36-cell model is given with all technical details in [5]. Computation cost of matrix inversion in electromagnetic imaging is reduced by exploiting symmetry using group theory in [6, 7]. Pseudo inverse transformation is applied on matrix to solve electromagnetic problem in [8]. Dielectric profile reconstruction of human arm and horse kidney is shown using models in [9]. Dielectric profile reconstruction using stochastic technique known as simulated annealing is described greatly in [10]. Multi frequency scattering data is used for shape and location reconstruction in [11]. A classical model driven approach is given for biomedical applications in [12]. Different stochastic methods, to solve inverse scattering problem for microwave imaging are reviewed in [13]. Singular value decomposition is used to solve inverse scattering problem in [14]. Hybrid reconstruction technique using Levenberg-Marquardt and genetic algorithm is described in detail [15]. Gauss-Newton and conjugate gradient least square algorithms are used to solve
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Recent advances in the effects of microwave radiation on brains

Recent advances in the effects of microwave radiation on brains

frequency radiation (FR) and miRNAs. Studies have also suggested that long-term exposure to 2.4 GHz microwave radiation may lead to adverse effects, as observed in neurodegenerative diseases that originate from the altered expression of some miRNAs. The authors found that 2.4 GHz microwave radiation reduced the expression of some miRNAs such as miR-106b-5p and miR-107 [98]. Zhao et al. [99] used a microarray and quantitative real- time PCR to analyze the miRNA expression profile in the hippocampus on days 7 and 14 after irradiation with a microwave at 30 mW/cm 2 . The authors predicted the dif- ferential expression of genes associated with transcription, translation and receptor functions (in addition to brain- related and signaling pathway-related) using the iRDB, miRbase and miRanda databases. They summarized the characteristics and functions of hippocampus-related miR- NAs following irradiation with microwaves, and these data laid a foundation that clarified the molecular mechanisms underlying microwave-induced injury to hippocampal learning and memory and suggested potential therapeutic targets. To investigate the effects of 2.4 GHz Wi-Fi radi- ation on multisensory integration in rats, a cross-modal visual-tactile object recognition (CMOR) task was per- formed by four variations of the spontaneous object rec- ognition (SOR) test including the standard SOR, tactile SOR, visual SOR, and CMOR tests. The results of this study showed that chronic exposure to Wi-Fi electromag- netic waves might impair both unimodal and cross-modal encoding of information. The increase in M1 receptor gene expression along with the impairment of novel pref- erences in Wi-Fi-exposed animals may suggest a possible role of the cholinergic system in the detrimental effects of Wi-Fi radiation on multisensory integration [100].
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THE UNIVERSITY OF ALBERTA EDMONTON, ALBERTA, CANADA

THE UNIVERSITY OF ALBERTA EDMONTON, ALBERTA, CANADA

c) Photocopying → Electronic document capture: High speed scanning workstations have been installed in each branch library replacing photocopiers. The 30ppm pedal-activated scanner has been modified to deal with bound documents and high volumes, and tied into a Windows-based scanning software utilizing touch-screen controls. The resulting image file is now available for a range of Internet-based delivery options. This is the only manual operation left in the lending and copying cycle.

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An Support Vector Regression Based Nonlinear Modeling Method for Sic Mesfet

An Support Vector Regression Based Nonlinear Modeling Method for Sic Mesfet

Abstract—An approach for the microwave nonlinear device modeling technique based on a combination of the conventional equivalent circuit model and support vector machine (SVM) regression is presented in this paper. The intrinsic nonlinear circuit elements are represented by Taylor series expansions, coefficients of which are predicted by its support vector regression (SVR) model. Example of a SiC MESFET nonlinear model is demonstrated, and good results is achieved.

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REVIEW OF AVAILABLE DATA FOR ASSESSMENT OF NON-INTRUSIVE DIAGNOSTIC METHODS FOR INTERNAL MATERIAL PROCESS DIAGNOSTICS - EXECUTIVE SUMMARY

REVIEW OF AVAILABLE DATA FOR ASSESSMENT OF NON-INTRUSIVE DIAGNOSTIC METHODS FOR INTERNAL MATERIAL PROCESS DIAGNOSTICS - EXECUTIVE SUMMARY

An extensive survey of non-intrusive experimental techniques has been undertaken in relation with plasma wind-tunnel tests (PWT) of ablative materials accounting for the efforts performed in the previous work package [9]. The techniques in use for the development of non-space applications such as medicine, energy, chemical engineering and electronics have been considered. This survey takes advantages of a previous effort [10] done for the experimental investigation of tank sloshing. Here, a particular effort has been dedicated to electric and ultrasound techniques since these techniques are cheap and being developed for TPS investigation. Other methods based on radiation, microwave, magnetic, and holographic approaches have been also considered in the current effort.
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Exploiting macrophages as targeted carrier to guide nanoparticles into glioma

Exploiting macrophages as targeted carrier to guide nanoparticles into glioma

In vivo imaging experiments were performed to evaluate the behavior of M-NPs in nude mice bearing intracranial U87 glioma. The accumulation of NPs in tumors via passive EPR effect was limited, while M-NPs exhibited a significant superiority in glioma targeting with high fluorescent intensity at all-time points. Consistently, in frozen brain sections, the accumulation of NPs was low and located on the border of glioma. However, M-NPs showed an extensive distribution and deep penetration into glioma parenchyma, indicating circulating macrophages could overcome the barriers (BBB, BBTB, IFP) and penetrate into the tumor tissue. The major organs, including heart, liver, spleen, lung, kidney, and brain, were harvested 24 hours after the administration of M-NPs and
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Parallel preconditioners and high order elements for microwave imaging

Parallel preconditioners and high order elements for microwave imaging

A novel competitive technique with these traditional imaging modalities is microwave tomography. With microwave imaging in a range of frequencies between 100 MHz and several GHz, the tissues are well differentiated and they can be imaged on the basis of their dielectric properties. The electromagnetic emissions are lower than the ones from mobile phones and the spatial resolution is good ( 5 − 7 mm). The first works on microwave imaging date back to 1989 when Lin and Clark tested experimentally the detection of cerebral edema (excessive accumulation of water in the brain) using a frequency signal of 2.4 GHz in a head phantom. Other works followed, but almost always on phantoms or synthetic simplified models [1]. Despite these encouraging results, there is still no microwave device for medical diagnosis. The techniques designed by the University of Chalmers (Gothenburg, Sweden) [2] and by EMTensor GmbH (Vienna, Austria) [3] rely on technologies and softwares developed only in recent years. In both cases the improvement in terms of reliability, price and miniaturization of electromagnetic sensors is a key factor. In this approach, it is necessary to transfer the data to a remote HPC machine. The rapid telephony standards such as 4G and 5G allow to send the acquired measurements of the patient’s brain to a supercomputer that will compute the 3D images. Then these images can be quickly transmitted from the computer to the hospital by ADSL or fiber network.
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Development of Microwave Imaging Diagnostics on the HL-2A Tokamak

Development of Microwave Imaging Diagnostics on the HL-2A Tokamak

The reflected waves from the cutoff surfaces in the plasma are focused via the same optical system onto the horn receiver array (HRA). The HRA is composed of 8 (poloidal) × 2 (toroidal) horn antennas. As shown in Fig. 1, the focal plane is a U-shaped surface obtained from simula- tion and modified by laboratory test. The antennas should be installed on the U-shaped focal surface. To match the focal surface, each antenna is designed to be adjusted in the vertical and horizontal directions. The received wave is amplified and then divided into four channels in a wide- band 4-way power divider. Four band-pass filters with pass frequencies of 32, 34, 36, and 38 GHz are used to separate the reflected waves from the different cutoff sur- faces. Then, the four reflected frequencies are separately demodulated with the reference signals in the quadrature detectors. The reflected wave can be written as Ae i φ e i ω t , where ω is the launching frequency, and A and φ repre- sent the amplitude and the phase caused by density fluctu- ation, respectively. In the quadrature detector, the in-phase (I ∝ A cos(φ)) and the quadrature (Q ∝ A sin(φ)) signals are finally obtained. The IQ signals are low pass filtered with a bandwidth of 1 MHz and video amplified. Finally, the IQ signals are converted to digital signals by 16 bit dig- itizers, capable of storing 1.25 Msamples per channel at a maximum sampling rate of 1.25 Msamples/s.
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