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1.
IET Syst Biol ; 18(4): 119-128, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38789402

RESUMO

Cancer treatment often involves heat therapy, commonly administered alongside chemotherapy and radiation therapy. The authors address the challenges posed by heat treatment methods and introduce effective control techniques. These approaches enable the precise adjustment of laser radiation over time, ensuring the tumour's core temperature attains an acceptable level with a well-defined transient response. In these control strategies, the input is the actual tumour temperature compared to the desired value, while the output governs laser radiation power. Efficient control methods are explored for regulating tumour temperature in the presence of nanoparticles and laser radiation, validated through simulations on a relevant physiological model. Initially, a Proportional-Integral-Derivative (PID) controller serves as the foundational compensator. The PID controller parameters are optimised using a combination of trial and error and the Imperialist Competitive Algorithm (ICA). ICA, known for its swift convergence and reduced computational complexity, proves instrumental in parameter determination. Furthermore, an intelligent controller based on an artificial neural network is integrated with the PID controller and compared against alternative methods. Simulation results underscore the efficacy of the combined neural network-PID controller in achieving precise temperature control. This comprehensive study illuminates promising avenues for enhancing heat therapy's effectiveness in cancer treatment.


Assuntos
Nanopartículas , Neoplasias , Humanos , Nanopartículas/química , Nanopartículas/uso terapêutico , Neoplasias/radioterapia , Hipertermia Induzida/métodos , Lasers , Temperatura Alta , Modelos Biológicos , Algoritmos , Redes Neurais de Computação , Simulação por Computador
2.
IET Syst Biol ; 13(5): 260-266, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31538960

RESUMO

Attention deficit hyperactivity disorder (ADHD) is a common behavioural disorder that may be found in 5%-8% of the children. Early diagnosis of ADHD is crucial for treating the disease and reducing its harmful effects on education, employment, relationships, and life quality. On the other hand, non-linear analysis methods are widely applied in processing the electroencephalogram (EEG) signals. It has been proved that the brain neuronal activity and its related EEG signals have chaotic behaviour. Hence, chaotic indices can be employed to classify the EEG signals. In this study, a new approach is proposed based on the combination of some non-linear features to distinguish ADHD from normal children. Lyapunov exponent, fractal dimension, correlation dimension and sample, fuzzy and approximate entropies are the non-linear extracted features. For computing, the chaotic time series of obtained EEG in the brain frontal lobe (FP1, FP2, F3, F4, and Fz) need to be analysed. Experiments on a set of EEG signal obtained from 50 ADHD and 26 normal cases yielded a sensitivity, specificity, and accuracy of 98, 92.31, and 96.05%, respectively. The obtained accuracy provides a significant improvement in comparison to the other similar studies in identifying and classifying children with ADHD.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Eletroencefalografia , Dinâmica não Linear , Processamento de Sinais Assistido por Computador , Adolescente , Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Encéfalo/fisiopatologia , Criança , Pré-Escolar , Feminino , Humanos , Masculino
3.
IET Syst Biol ; 13(1): 1-7, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30774110

RESUMO

In this study, three non-linear indices consist of compression, one-dimensional (1D) and two-dimensional (2D) fractal dimensions are used for the determination of the malignancy or benignity of cancer tumours in breast thermograms. On the other hand, by developing the high-precision infrared cameras as well as new methods of image processing, biomedical thermography images have found a prominent position among the others. Furthermore, cancerous tissue can be affected by the laser. In this study, in order to treat the cancerous lesion identified by breast thermograms, the laser parameters are designed. The basis of controller designing is the obtained non-linear indices. If the indices are moved from the chaotic behaviour to normal condition, the treating tissue is going from cancerous to a healthy condition and the treatment process is completed. Radiation frequency and the energy density of laser are designed as two key elements in the cancer treatment. In this study, the type I and type II fuzzy controllers are employed for the control strategies. Using the proposed closed-loop control, the non-linear indices of the cancerous lesion will be reduced during the treatment process. The simulation results on two datasets of breast thermograms indicate the superiority of type II fuzzy controller.


Assuntos
Neoplasias da Mama/diagnóstico , Fractais , Termografia , Análise por Conglomerados , Lógica Fuzzy , Humanos , Processamento de Imagem Assistida por Computador , Dinâmica não Linear , Incerteza
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