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1.
J Med Syst ; 39(10): 314, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26289629

RESUMO

Indirect immunofluorescence technique applied on HEp-2 cell substrates provides the major screening method to detect ANA patterns in the diagnosis of autoimmune diseases. Currently, the ANA patterns are mostly inspected by experienced physicians to identify abnormal cell patterns. The objective of this study is to design a computer-assisted system to automatically detect cell patterns of IIF images for the diagnosis of autoimmune diseases in the clinical setting. The system simulates the functions of modern flow cytometer and provides the diagnostic reports generated by the system to the technicians and physicians through the radar graphs, box-plots, and tables. The experimental results show that, among the IIF images collected from 17 patients, 6 were classified as coarse-speckled, 3 as diffused, 2 as discrete-speckled, 1 as fine-speckled, 2 as nucleolar, and 3 as peripheral patterns, which were consistent with the patterns determined by the physicians. In addition to recognition of cell patterns, the system also provides the function to automatically generate the report for each patient. The time needed for the whole procedure is less than 30 min, which is more efficient than the manual operation of the physician after inspecting the ANA IIF images. Besides, the system can be easily deployed on many desktop and laptop computers. In conclusion, the designed system, containing functions for automatic detection of ANA cell pattern and generation of diagnostic report, is effective and efficient to assist physicians to diagnose patients with autoimmune diseases. The limitations of the current developed system include (1) only a unique cell pattern was considered for the IIF images collected from a patient, and (2) the cells during the process of mitosis were not adopted for cell classification.


Assuntos
Doenças Autoimunes/diagnóstico , Doenças Autoimunes/patologia , Diagnóstico por Computador/instrumentação , Técnica Indireta de Fluorescência para Anticorpo/instrumentação , Reconhecimento Automatizado de Padrão , Citometria de Fluxo , Humanos
2.
Biomed Eng Online ; 12 Suppl 1: S5, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24565042

RESUMO

Autoimmune disease is a disorder of immune system due to the over-reaction of lymphocytes against one's own body tissues. Anti-Nuclear Antibody (ANA) is an autoantibody produced by the immune system directed against the self body tissues or cells, which plays an important role in the diagnosis of autoimmune diseases. Indirect ImmunoFluorescence (IIF) method with HEp-2 cells provides the major screening method to detect ANA for the diagnosis of autoimmune diseases. Fluorescence patterns at present are usually examined laboriously by experienced physicians through manually inspecting the slides with the help of a microscope, which usually suffers from inter-observer variability that limits its reproducibility. Previous researches only provided simple segmentation methods and criterions for cell segmentation and recognition, but a fully automatic framework for the segmentation and recognition of HEp-2 cells had never been reported before. This study proposes a method based on the watershed algorithm to automatically detect the HEp-2 cells with different patterns. The experimental results show that the segmentation performance of the proposed method is satisfactory when evaluated with percent volume overlap (PVO: 89%). The classification performance using a SVM classifier designed based on the features calculated from the segmented cells achieves an average accuracy of 96.90%, which outperforms other methods presented in previous studies. The proposed method can be used to develop a computer-aided system to assist the physicians in the diagnosis of auto-immune diseases.


Assuntos
Anticorpos Antinucleares/isolamento & purificação , Doenças Autoimunes/diagnóstico , Algoritmos , Técnica Indireta de Fluorescência para Anticorpo , Células Hep G2 , Humanos , Processamento de Imagem Assistida por Computador , Modelos Teóricos , Variações Dependentes do Observador , Reconhecimento Automatizado de Padrão/métodos , Reprodutibilidade dos Testes
3.
IEEE Trans Syst Man Cybern B Cybern ; 42(1): 150-62, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21878416

RESUMO

In this paper, we propose a novel possibilistic fuzzy matching strategy with invariant properties, which can provide a robust and effective matching scheme for two sets of iris feature points. In addition, the nonlinear normalization model is adopted to provide more accurate position before matching. Moreover, an effective iris segmentation method is proposed to refine the detected inner and outer boundaries to smooth curves. For feature extraction, the Gabor filters are adopted to detect the local feature points from the segmented iris image in the Cartesian coordinate system and to generate a rotation-invariant descriptor for each detected point. After that, the proposed matching algorithm is used to compute a similarity score for two sets of feature points from a pair of iris images. The experimental results show that the performance of our system is better than those of the systems based on the local features and is comparable to those of the typical systems.


Assuntos
Algoritmos , Inteligência Artificial , Biometria/métodos , Lógica Fuzzy , Interpretação de Imagem Assistida por Computador/métodos , Iris/anatomia & histologia , Reconhecimento Automatizado de Padrão/métodos , Retinoscopia/métodos , Técnica de Subtração , Humanos
4.
IEEE Trans Syst Man Cybern B Cybern ; 41(3): 828-39, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21189244

RESUMO

In this paper, the interval type-2 fuzzy controllers (FC(IT2)s) are approximated using the fuzzy ratio switching type-1 FCs to avoid the complex type-reduction process required for the interval type-2 FCs. The fuzzy ratio switching type-1 FCs (FC(FRST1)s) are designed to be a fuzzy combination of the possible-leftmost and possible-rightmost type-1 FCs. The fuzzy ratio switching type-1 fuzzy control technique is applied with the sliding control technique to realize the hybrid fuzzy ratio switching type-1 fuzzy sliding controllers (HFSC(FRST1)s) for the double-pendulum-and-cart system. The simulation results and comparisons with other approaches are provided to demonstrate the effectiveness of the proposed HFSC(FRST1)s.


Assuntos
Inteligência Artificial , Retroalimentação , Lógica Fuzzy , Modelos Teóricos , Dinâmica não Linear , Processamento de Sinais Assistido por Computador , Algoritmos , Simulação por Computador
5.
IEEE Trans Syst Man Cybern B Cybern ; 40(1): 241-52, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19661002

RESUMO

In this paper, an adaptive fuzzy switched swing-up and sliding controller (AFSSSC) is proposed for the swing-up and position controls of a double-pendulum-and-cart system. The proposed AFSSSC consists of a fuzzy switching controller (FSC), an adaptive fuzzy swing-up controller (FSUC), and an adaptive hybrid fuzzy sliding controller (HFSC). To simplify the design of the adaptive HFSC, the double-pendulum-and-cart system is reformulated as a double-pendulum and a cart subsystem with matched time-varying uncertainties. In addition, an adaptive mechanism is provided to learn the parameters of the output fuzzy sets for the adaptive HFSC. The FSC is designed to smoothly switch between the adaptive FSUC and the adaptive HFSC. Moreover, the sliding mode and the stability of the fuzzy sliding control systems are guaranteed. Simulation results are included to illustrate the effectiveness of the proposed AFSSSC.

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