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1.
Sensors (Basel) ; 19(2)2019 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-30669319

RESUMO

Home monitoring and remote care systems aim to ultimately provide independent living care scenarios through non-intrusive, privacy-protecting means. Their main aim is to provide care through appreciating normal habits, remotely recognizing changes and acting upon those changes either through informing the person themselves, care providers, family members, medical practitioners, or emergency services, depending on need. Care giving can be required at any age, encompassing young to the globally growing aging population. A non-wearable and unobtrusive architecture has been developed and tested here to provide a fruitful health and wellbeing-monitoring framework without interfering in a user's regular daily habits and maintaining privacy. This work focuses on tracking locations in an unobtrusive way, recognizing daily activities, which are part of maintaining a healthy/regular lifestyle. This study shows an intelligent and locally based edge care system (ECS) solution to identify the location of an occupant's movement from daily activities using impulse radio-ultra wide band (IR-UWB) radar. A new method is proposed calculating the azimuth angle of a movement from the received pulse and employing radar principles to determine the range of that movement. Moreover, short-term fourier transform (STFT) has been performed to determine the frequency distribution of the occupant's action. Therefore, STFT, azimuth angle, and range calculation together provide the information to understand how occupants engage with their environment. An experiment has been carried out for an occupant at different times of the day during daily household activities and recorded with time and room position. Subsequently, these time-frequency outcomes, along with the range and azimuth information, have been employed to train a support vector machine (SVM) learning algorithm for recognizing indoor locations when the person is moving around the house, where little or no movement indicates the occurrence of abnormalities. The implemented framework is connected with a cloud server architecture, which enables to act against any abnormality remotely. The proposed methodology shows very promising results through statistical validation and achieved over 90% testing accuracy in a real-time scenario.

2.
Sensors (Basel) ; 18(11)2018 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-30400362

RESUMO

Unobtrusive indoor location systems must rely on methods that avoid the deployment of large hardware infrastructures or require information owned by network administrators. Fingerprinting methods can work under these circumstances by comparing the real-time received RSSI values of a smartphone coming from existing Wi-Fi access points with a previous database of stored values with known locations. Under the fingerprinting approach, conventional methods suffer from large indoor scenarios since the number of fingerprints grows with the localization area. To that aim, fingerprinting-based localization systems require fast machine learning algorithms that reduce the computational complexity when comparing real-time and stored values. In this paper, popular machine learning (ML) algorithms have been implemented for the classification of real time RSSI values to predict the user location and propose an intelligent indoor positioning system (I-IPS). The proposed I-IPS has been integrated with multi-agent framework for betterment of context-aware service (CAS). The obtained results have been analyzed and validated through established statistical measurements and superior performance achieved.

3.
Tomography ; 9(1): 105-129, 2023 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-36648997

RESUMO

Mammography is the gold standard technology for breast screening, which has been demonstrated through different randomized controlled trials to reduce breast cancer mortality. However, mammography has limitations and potential harms, such as the use of ionizing radiation. To overcome the ionizing radiation exposure issues, a novel device (i.e. MammoWave) based on low-power radio-frequency signals has been developed for breast lesion detection. The MammoWave is a microwave device and is under clinical validation phase in several hospitals across Europe. The device transmits non-invasive microwave signals through the breast and accumulates the backscattered (returned) signatures, commonly denoted as the S21 signals in engineering terminology. Backscattered (complex) S21 signals exploit the contrast in dielectric properties of breasts with and without lesions. The proposed research is aimed to automatically segregate these two types of signal responses by applying appropriate supervised machine learning (ML) algorithm for the data emerging from this research. The support vector machine with radial basis function has been employed here. The proposed algorithm has been trained and tested using microwave breast response data collected at one of the clinical validation centres. Statistical evaluation indicates that the proposed ML model can recognise the MammoWave breasts signal with no radiological finding (NF) and with radiological findings (WF), i.e., may be the presence of benign or malignant lesions. A sensitivity of 84.40% and a specificity of 95.50% have been achieved in NF/WF recognition using the proposed ML model.


Assuntos
Neoplasias da Mama , Micro-Ondas , Humanos , Feminino , Mama/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Aprendizado de Máquina Supervisionado , Tecnologia
4.
PLoS One ; 17(7): e0271377, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35862368

RESUMO

MammoWave is a microwave imaging device for breast lesion detection, employing two antennas which rotate azimuthally (horizontally) around the breast. The antennas operate in the 1-9 GHz band and are set in free space, i.e., pivotally, no matching liquid is required. Microwave images, subsequently obtained through the application of Huygens Principle, are intensity maps, representing the homogeneity of the dielectric properties of the breast tissues under test. In this paper, MammoWave is used to realise tissues dielectric differences and localise lesions by segmenting microwave images adaptively employing pulse coupled neural network (PCNN). Subsequently, a non-parametric thresholding technique is modelled to differentiate between breasts having no radiological finding (NF) or benign (BF) and breasts with malignant finding (MF). Resultant findings verify that automated breast lesion localization with microwave imaging matches the gold standard achieving 81.82% sensitivity in MF detection. The proposed method is tested on microwave images acquired from a feasibility study performed in Foligno Hospital, Italy. This study is based on 61 breasts from 35 patients; performance may vary with larger number of datasets and will be subsequently investigated.


Assuntos
Neoplasias da Mama , Imageamento de Micro-Ondas , Algoritmos , Mama/diagnóstico por imagem , Mama/patologia , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Diagnóstico por Imagem , Feminino , Humanos , Micro-Ondas , Redes Neurais de Computação
5.
Diagnostics (Basel) ; 11(10)2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-34679628

RESUMO

Recently, a novel microwave apparatus for breast lesion detection (MammoWave), uniquely able to function in air with 2 antennas rotating in the azimuth plane and operating within the band 1-9 GHz has been developed. Machine learning (ML) has been implemented to understand information from the frequency spectrum collected through MammoWave in response to the stimulus, segregating breasts with and without lesions. The study comprises 61 breasts (from 35 patients), each one with the correspondent output of the radiologist's conclusion (i.e., gold standard) obtained from echography and/or mammography and/or MRI, plus pathology or 1-year clinical follow-up when required. The MammoWave examinations are performed, recording the frequency spectrum, where the magnitudes show substantial discrepancy and reveals dissimilar behaviours when reflected from tissues with/without lesions. Principal component analysis is implemented to extract the unique quantitative response from the frequency response for automated breast lesion identification, engaging the support vector machine (SVM) with a radial basis function kernel. In-vivo feasibility validation (now ended) of MammoWave was approved in 2015 by the Ethical Committee of Umbria, Italy (N. 6845/15/AV/DM of 14 October 2015, N. 10352/17/NCAV of 16 March 2017, N 13203/18/NCAV of 17 April 2018). Here, we used a set of 35 patients. According to the radiologists conclusions, 25 breasts without lesions and 36 breasts with lesions underwent a MammoWave examination. The proposed SVM model achieved the accuracy, sensitivity, and specificity of 91%, 84.40%, and 97.20%. The proposed ML augmented MammoWave can identify breast lesions with high accuracy.

6.
Annu Int Conf IEEE Eng Med Biol Soc ; 2019: 782-787, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31946012

RESUMO

A more locally cared for and self-managing aging population along with better attention to self health-care, has resulted in increasing need for non-intrusive monitoring. Wearable, wireless physiological sensors, and cameras can pose user privacy, security and discomfort issues which may have a negative impact on consumer confidence and uptake. Thus, for the first time a non-contact, non-intrusive 3D human motion model is proposed for gait disorder identification from impulse radio ultra-wide band (ITERATOR) with the understanding of spherical trigonometry and vector field. Simultaneously, the Kinect Xbox One is used to compare the outcomes of the proposed IR-UWB model. The experiment comprises twenty-four human participants, where twenty people have normal walking pattern and four persons have spasticity. The height of different body sections from the ground have been recorded for each individual and employed later to distinguish lower and upper human body from the outcomes. The proposed work has transformed the radars backscattered responses through trigonometry and vector algebra where, only vector algebra has been implemented to transform the skeletal data obtained from Kinect. Angles between two thighs have been determined from the proposed UWB algorithm and validated against angles obtained from the Kinect skeletal data using root mean square error (RMSE), where less than 0.5 RMSE has been found.


Assuntos
Marcha , Algoritmos , Humanos , Tecnologia sem Fio
7.
Sci Rep ; 9(1): 10510, 2019 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-31324863

RESUMO

Breast lesion detection employing state of the art microwave systems provide a safe, non-ionizing technique that can differentiate healthy and non-healthy tissues by exploiting their dielectric properties. In this paper, a microwave apparatus for breast lesion detection is used to accumulate clinical data from subjects undergoing breast examinations at the Department of Diagnostic Imaging, Perugia Hospital, Perugia, Italy. This paper presents the first ever clinical demonstration and comparison of a microwave ultra-wideband (UWB) device augmented by machine learning with subjects who are simultaneously undergoing conventional breast examinations. Non-ionizing microwave signals are transmitted through the breast tissue and the scattering parameters (S-parameter) are received via a dedicated moving transmitting and receiving antenna set-up. The output of a parallel radiologist study for the same subjects, performed using conventional techniques, is taken to pre-process microwave data and create suitable data for the machine intelligence system. These data are used to train and investigate several suitable supervised machine learning algorithms nearest neighbour (NN), multi-layer perceptron (MLP) neural network, and support vector machine (SVM) to create an intelligent classification system towards supporting clinicians to recognise breasts with lesions. The results are rigorously analysed, validated through statistical measurements, and found the quadratic kernel of SVM can classify the breast data with 98% accuracy.


Assuntos
Mama/diagnóstico por imagem , Imageamento de Micro-Ondas , Redes Neurais de Computação , Máquina de Vetores de Suporte , Algoritmos , Neoplasias da Mama/diagnóstico por imagem , Ensaios Clínicos como Assunto , Espectroscopia Dielétrica/instrumentação , Espectroscopia Dielétrica/métodos , Desenho de Equipamento , Feminino , Humanos , Imageamento por Ressonância Magnética , Mamografia , Curva ROC , Espalhamento de Radiação , Estatísticas não Paramétricas , Ultrassonografia Mamária
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