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1.
Sensors (Basel) ; 22(5)2022 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-35270994

RESUMO

In this paper, we addressed the problem of dataset scarcity for the task of network intrusion detection. Our main contribution was to develop a framework that provides a complete process for generating network traffic datasets based on the aggregation of real network traces. In addition, we proposed a set of tools for attribute extraction and labeling of traffic sessions. A new dataset with botnet network traffic was generated by the framework to assess our proposed method with machine learning algorithms suitable for unbalanced data. The performance of the classifiers was evaluated in terms of macro-averages of F1-score (0.97) and the Matthews Correlation Coefficient (0.94), showing a good overall performance average.


Assuntos
Algoritmos , Aprendizado de Máquina , Projetos de Pesquisa
2.
JMIR Mhealth Uhealth ; 8(7): e18012, 2020 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-32459642

RESUMO

BACKGROUND: Smartphone-based blood pressure (BP) monitoring using photoplethysmography (PPG) technology has emerged as a promising approach to empower users with self-monitoring for effective diagnosis and control of hypertension. OBJECTIVE: This study aimed to develop a mobile personal health care system for noninvasive, pervasive, and continuous estimation of BP level and variability, which is user friendly for elderly people. METHODS: The proposed approach was integrated by a self-designed cuffless, calibration-free, wireless, and wearable PPG-only sensor and a native purposely designed smartphone app using multilayer perceptron machine learning techniques from raw signals. We performed a development and usability study with three older adults (mean age 61.3 years, SD 1.5 years; 66% women) to test the usability and accuracy of the smartphone-based BP monitor. RESULTS: The employed artificial neural network model had good average accuracy (>90%) and very strong correlation (>0.90) (P<.001) for predicting the reference BP values of our validation sample (n=150). Bland-Altman plots showed that most of the errors for BP prediction were less than 10 mmHg. However, according to the Association for the Advancement of Medical Instrumentation and British Hypertension Society standards, only diastolic blood pressure prediction met the clinically accepted accuracy thresholds. CONCLUSIONS: With further development and validation, the proposed system could provide a cost-effective strategy to improve the quality and coverage of health care, particularly in rural zones, areas lacking physicians, and areas with solitary elderly populations.


Assuntos
Determinação da Pressão Arterial , Aplicativos Móveis , Fotopletismografia , Idoso , Pressão Sanguínea , Atenção à Saúde , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica
3.
Sensors (Basel) ; 19(9)2019 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-31064133

RESUMO

With the rapid deployment of the Internet of Things and cloud computing, it is necessary to enhance authentication protocols to reduce attacks and security vulnerabilities which affect the correct performance of applications. In 2019 a new lightweight IoT-based authentication scheme in cloud computing circumstances was proposed. According to the authors, their protocol is secure and resists very well-known attacks. However, when we evaluated the protocol we found some security vulnerabilities and drawbacks, making the scheme insecure. Therefore, we propose a new version considering login, mutual authentication and key agreement phases to enhance the security. Moreover, we include a sub-phase called evidence of connection attempt which provides proof about the participation of the user and the server. The new scheme achieves the security requirements and resists very well-known attacks, improving previous works. In addition, the performance evaluation demonstrates that the new scheme requires less communication-cost than previous authentication protocols during the registration and login phases.

4.
Comput Math Methods Med ; 2018: 9128054, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30002725

RESUMO

Mobile electrocardiogram (ECG) monitoring is an emerging area that has received increasing attention in recent years, but still real-life validation for elderly residing in low and middle-income countries is scarce. We developed a wearable ECG monitor that is integrated with a self-designed wireless sensor for ECG signal acquisition. It is used with a native purposely designed smartphone application, based on machine learning techniques, for automated classification of captured ECG beats from aged people. When tested on 100 older adults, the monitoring system discriminated normal and abnormal ECG signals with a high degree of accuracy (97%), sensitivity (100%), and specificity (96.6%). With further verification, the system could be useful for detecting cardiac abnormalities in the home environment and contribute to prevention, early diagnosis, and effective treatment of cardiovascular diseases, while keeping costs down and increasing access to healthcare services for older persons.


Assuntos
Arritmias Cardíacas/diagnóstico , Eletrocardiografia/instrumentação , Processamento de Sinais Assistido por Computador , Smartphone , Telemedicina , Idoso , Automação , Humanos , Monitorização Fisiológica
5.
J Am Heart Assoc ; 6(10)2017 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-29051214

RESUMO

BACKGROUND: Although 24-hour blood pressure (BP) variability (BPV) is predictive of cardiovascular outcomes independent of absolute BP levels, it is not regularly assessed in clinical practice. One possible limitation to routine BPV assessment is the lack of standardized methods for accurately estimating 24-hour BPV. We conducted a systematic review to assess the predictive power of reported BPV indexes to address appropriate quantification of 24-hour BPV, including the average real variability (ARV) index. METHODS AND RESULTS: Studies chosen for review were those that presented data for 24-hour BPV in adults from meta-analysis, longitudinal or cross-sectional design, and examined BPV in terms of the following issues: (1) methods used to calculate and evaluate ARV; (2) assessment of 24-hour BPV determined using noninvasive ambulatory BP monitoring; (3) multivariate analysis adjusted for covariates, including some measure of BP; (4) association of 24-hour BPV with subclinical organ damage; and (5) the predictive value of 24-hour BPV on target organ damage and rate of cardiovascular events. Of the 19 assessed studies, 17 reported significant associations between high ARV and the presence and progression of subclinical organ damage, as well as the incidence of hard end points, such as cardiovascular events. In all these cases, ARV remained a significant independent predictor (P<0.05) after adjustment for BP and other clinical factors. In addition, increased ARV in systolic BP was associated with risk of all cardiovascular events (hazard ratio, 1.18; 95% confidence interval, 1.09-1.27). Only 2 cross-sectional studies did not find that high ARV was a significant risk factor. CONCLUSIONS: Current evidence suggests that ARV index adds significant prognostic information to 24-hour ambulatory BP monitoring and is a useful approach for studying the clinical value of BPV.


Assuntos
Pressão Sanguínea , Doenças Cardiovasculares/fisiopatologia , Ritmo Circadiano , Adulto , Idoso , Monitorização Ambulatorial da Pressão Arterial , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Reprodutibilidade dos Testes , Medição de Risco , Fatores de Risco , Fatores de Tempo
6.
Comput Math Methods Med ; 2013: 598196, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23762189

RESUMO

The ARVmobile v1.0 is a multiplatform mobile personal health monitor (PHM) application for ambulatory blood pressure (ABP) monitoring that has the potential to aid in the acquisition and analysis of detailed profile of ABP and heart rate (HR), improve the early detection and intervention of hypertension, and detect potential abnormal BP and HR levels for timely medical feedback. The PHM system consisted of ABP sensor to detect BP and HR signals and smartphone as receiver to collect the transmitted digital data and process them to provide immediate personalized information to the user. Android and Blackberry platforms were developed to detect and alert of potential abnormal values, offer friendly graphical user interface for elderly people, and provide feedback to professional healthcare providers via e-mail. ABP data were obtained from twenty-one healthy individuals (>51 years) to test the utility of the PHM application. The ARVmobile v1.0 was able to reliably receive and process the ABP readings from the volunteers. The preliminary results demonstrate that the ARVmobile 1.0 application could be used to perform a detailed profile of ABP and HR in an ordinary daily life environment, bedsides of estimating potential diagnostic thresholds of abnormal BP variability measured as average real variability.


Assuntos
Telemedicina/instrumentação , Idoso , Pressão Sanguínea , Monitorização Ambulatorial da Pressão Arterial/estatística & dados numéricos , Telefone Celular , Biologia Computacional , Diagnóstico por Computador , Desenho de Equipamento , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica/instrumentação , Monitorização Fisiológica/estatística & dados numéricos , Processamento de Sinais Assistido por Computador , Software , Telemedicina/estatística & dados numéricos , Interface Usuário-Computador
7.
Comput Math Methods Med ; 2012: 750151, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22924062

RESUMO

Machine learning has become a powerful tool for analysing medical domains, assessing the importance of clinical parameters, and extracting medical knowledge for outcomes research. In this paper, we present a machine learning method for extracting diagnostic and prognostic thresholds, based on a symbolic classification algorithm called REMED. We evaluated the performance of our method by determining new prognostic thresholds for well-known and potential cardiovascular risk factors that are used to support medical decisions in the prognosis of fatal cardiovascular diseases. Our approach predicted 36% of cardiovascular deaths with 80% specificity and 75% general accuracy. The new method provides an innovative approach that might be useful to support decisions about medical diagnoses and prognoses.


Assuntos
Inteligência Artificial , Doenças Cardiovasculares/diagnóstico , Idoso , Algoritmos , Monitorização Ambulatorial da Pressão Arterial/instrumentação , Monitorização Ambulatorial da Pressão Arterial/métodos , Doenças Cardiovasculares/patologia , Sistema Cardiovascular , Simulação por Computador , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Cardiovasculares , Prognóstico , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Processamento de Sinais Assistido por Computador , Software
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