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1.
Australas J Dermatol ; 65(2): 114-127, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37941136

RESUMO

Of the 15 eligible studies identified via electronic searches in MEDLINE, EMBASE and CENTRAL in November 2022 for methotrexate therapy of moderate-to-severe atopic dermatitis, 12 were non-randomized controlled trial (non-RCT) studies with data from 437 patients (235 adults and 202 children). The response rates for short-term therapy were 77% [95% CI 55-99] (four studies; adults) - comparable to 81% [54-100] of RCTs (two studies; adults) (p = 0.63) - and 61% [43-79] (two studies; children), and for medium/long-term therapy were 88.9% [74.3-100.0] (four studies; adults) and 77.7% [61.5-94.0] (three studies; children). Children had a markedly lower rate of treatment discontinuation due to side effects [2.0% (five studies; children) vs. 14.9% (six studies; adults)], but were more likely to experience gastrointestinal disorders {relative risk (RR) 2.0 [1.44-2.71]}, fatigue (RR 2.3 [1.35-3.72]), headache (RR 2.8 [1.23-5.61]), and infections (RR 2.9 [2.18-3.58]). Other adverse events (children vs. adults) included hepatic disorders (32/176 vs. 35/305) and blood and lymphatic system/bone marrow disorders (25/148 vs. 19/184). Four serious adverse events were reported (children). Evidence from daily practice was limited by bias in the selection of participants in the study.


Assuntos
Dermatite Atópica , Adulto , Criança , Humanos , Dermatite Atópica/tratamento farmacológico , Metotrexato/efeitos adversos , Ensaios Clínicos Controlados não Aleatórios como Assunto
2.
Sensors (Basel) ; 23(6)2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36991787

RESUMO

This paper proposes a novel trajectory planning algorithm to design an end-effector motion profile along a specified path. An optimization model based on the whale optimization algorithm (WOA) is established for time-optimal asymmetrical S-curve velocity scheduling. Trajectories designed by end-effector limits may violate kinematic constraints due to the non-linear relationship between the operation and joint space of redundant manipulators. A constraints conversion approach is proposed to update end-effector limits. The path can be divided into segments at the minimum of the updated limitations. On each path segment, the jerk-limited S-shaped velocity profile is generated within the updated limitations. The proposed method aims to generate end-effector trajectory by kinematic constraints which are imposed on joints, resulting in efficient robot motion performance. The WOA-based asymmetrical S-curve velocity scheduling algorithm can be automatically adjusted for different path lengths and start/end velocities, allowing flexibility in finding the time-optimal solution under complex constraints. Simulations and experiments on a redundant manipulator prove the effect and superiority of the proposed method.

3.
Angew Chem Int Ed Engl ; 62(33): e202306333, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37345563

RESUMO

Rational design of efficient, stable, and inexpensive bifunctional electrocatalysts for oxygen evolution reactions (OER) and hydrogen evolution reactions (HER) is a key challenge to realize green hydrogen production via electrolytic water splitting. Herein, Ru nanoparticles and FeNi alloy heterojunction catalyst (Ru-FeNi@NLC) encapsulated via lignin-derived carbon was prepared by self-assembly precipitation and in situ pyrolysis. The designed catalyst displays excellent performance at 10 mA cm-2 with low overpotentials of 36 mV for HER and 198 mV for OER, and only needs 1.48 V for overall water splitting. Results and DFT calculations show the unique N-doped lignin-derived carbon layer and Ru-FeNi heterojunction contribute to optimized electronic structure for enhancing electron transfer, balanced free energy of reactants and intermediates in the sorption/desorption process, and significantly reduced reaction energy barrier for the HER and OER rate-determining steps, thus improved reaction kinetics. This work provides a new in situ pyrolysis doping strategy based on renewable biomass for the construction of highly active, stable and cost-effective catalysts.

4.
Appl Opt ; 61(12): 3349-3356, 2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35471430

RESUMO

We present the optomechanical design and development of a wide-field auroral imager (WAI) on board the satellite Fengyun-3D. The optomechanical system of the WAI features a combination of a large field of view and a single-axis scanning mechanism. The combination makes the WAI perform better than its counterparts in temporal resolution in a low Earth orbit. In-orbit tests have verified the survival of WAI in the launching vibration and space environment. It has functioned on-orbit since 2018, with a spatial resolution of ∼10km at the nadir point, at a reference height of 110 km above the ionosphere.

5.
Sensors (Basel) ; 22(18)2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-36146208

RESUMO

In order to solve the tracking accuracy problem of the redundant manipulator, a PI control method with Henry gas solubility optimization parameter regulator (PI-HGSO) is proposed in this paper. This method consists of the controller and the parameter regulator. The characteristic is that the position deviation of a manipulator is equivalent to a specific function; namely, the proportional-integral (PI) controller is used to adjust the deviation input. The error can be better corrected by the processing of the PI controller so that the inverse kinematics solution of the minimum error can be realized. At the same time, the parameter selection of PI controllers has always been a difficulty in controller design. To address the problem, Henry gas solubility optimization (HGSO) is selected as a parameter regulator to optimize the parameters and obtain the optimal controller, thereby achieving high-precision trajectory tracking. Experiments on 9-DOF redundant manipulator show that our method achieves competitive tracking accuracy in contrast with others. Meanwhile, the efficiency and accuracy of the PI controller are greatly guaranteed by using HGSO to automatically optimize controller parameters instead of making approximate adjustments through infinite manual trial and error. Therefore, the feasibility and competitive superiority of PI-HGSO is fully proved in trajectory planning of redundant manipulators.


Assuntos
Solubilidade , Fenômenos Biomecânicos
6.
J Cell Biochem ; 121(3): 2118-2126, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31625175

RESUMO

Circular RNAs (circRNAs) are important regulators in cancer growth and progression. Exosomes carry various molecules including RNA, protein, and lipid from one cell to another cell. But the role of circRNAs from the exosomes from prostate cancer patients are not elucidated. In this study, circ_0044516 was found upregulated in prostate cancer and the roles and molecular mechanism of Hsa_circ_0044516 (circ_0044516) was investigated. Firstly, the exosomes of prostate cancer patients were collected for human circRNAs microarray to screen the circRNA expression profile. There were 35 significantly expressed circRNAs with more than fivefolds from microarray analysis. Circ_0044516 was verified to be significantly upregulated in the exosomes from prostate cancer patients and the cell lines. Further investigation demonstrated that circ_0044516 downregulation inhibited the proliferation and metastasis of prostate cancer cells. By bioinformatics and luciferase reporter assays, circ_0044516 was verified to downregulate miR-29a-3p expression and negatively related to miR-29a-3p expression levels in prostate cancer. In a summary, the study indicated that circ_0044516 played an important role in prostate cancer cell survival and metastasis, which suggested that an oncogenic role of circ_0044516 in prostate cancer.


Assuntos
Biomarcadores Tumorais/genética , Proliferação de Células , Exossomos/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Neoplasias da Próstata/patologia , RNA Circular/genética , Apoptose , Movimento Celular , Humanos , Masculino , Metástase Neoplásica , Prognóstico , Neoplasias da Próstata/genética , Células Tumorais Cultivadas
7.
Opt Express ; 28(7): 9384-9392, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32225546

RESUMO

The strong coupling between photonic nanocavities at arbitrary positions is important for the realization of photonic integrated circuits. However, the coupling between nanocavities is mainly through the evanescent field, which limits the distance between nanocavities and hinders the scalability of photonic circuits. Here, we propose a scheme to realize the strong coupling between two distant nanocavities beyond the limitations of evanescent field coupling. Two distant identical one dimensional photonic crystal cavities (1DPhCCs) more than 8 µm apart are bridged by a microring which supports whispering gallery modes (WGMs). We demonstrate that the two 1DPhCCs can be strongly coupled even though the microring is largely detuned from them. The supermodes between the two 1DPhCCs are formed while the proportions of the WGM in the microring are suppressed at large detuning. The light energy mainly oscillates between the two 1DPhCCs, leaving the WGM in the microring as a dark mode. Such a scheme can realize strong coupling between distant nanocavities without much difficulties in experiments, which provides advantages for the realization of next-generation photonic circuits.

9.
Opt Express ; 27(15): 20211-20220, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31510119

RESUMO

Strong coupling between solid-state quantum emitters and microcavities paves the way for optical coherent manipulation of quantum state and provides opportunities for quantum information processing. However, it is still a challenge to realize strong coupling due to the spectral and spatial mismatch between quantum emitters and cavity modes. Here, we propose a scheme to tune the coupling between a single QD and a microdisk with 1D photonic crystal nanobeam cavity. Based on Finite-Difference Time-Domain (FDTD) method and Green's function expression for the evolution operator, we demonstrate that QDs with emission wavelengths +1.27 nm and -1.44 nm detuned from the bare microdisk mode can be coupled to the system strongly. Particularly, we observe simultaneous coupling between QD and two cavity supermodes, which enriches the optical coherent control methods of quantum states. By adjusting the distance between the two cavities, we can control the coupling between QD and photons. Furthermore, benefiting from the natural integration of nanobeam cavity to waveguide, such a system provides advantages for implementing quantum internet.

10.
BMC Cancer ; 19(1): 87, 2019 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-30658612

RESUMO

PURPOSE: To investigate whether free testosterone (FT) prior to radical prostatectomy was related to post-operative oncologic outcomes, erectile function and continence. METHODS: The data of 586 patients with available information underwent treatment in our center was retrospectively reviewed. Total testosterone (TT) was tested by chemiluminescence immunoassay, and FT value was calculated using Vermeulen's formula. Post-operative continence and erectile function were evaluated by the requirement of pad and the IIEF-5 score at 12 months. RESULTS: The median TT and FT value was 344 ng/dL (interquartile, IQR 314-374) and 6.9 ng/dL (IQR 6.4-7.3), and 106 patients (18.1%) and 152 patients (25.9%) were evaluated as having low TT and low FT based on current guidelines. Low TT and FT value were both related to older age (both p < 0.001), concomitant diabetes (p = 0.018 & 0.049), higher possibility of pre-operative erectile dysfunction (ED, both p < 0.001), higher pre-operative PSA value (both p < 0.001), higher clinical stage (both p < 0.001) and higher Gleason score in biopsy (both p < 0.001). Low FT was related to higher risk for pT3 (p = 0.020) and high Gleason score (p = 0.011) in logistic regression. The median follow-up duration was 52 moths (IQR 29-67) and FT was found to be an independent risk factor for biochemical recurrence (p = 0.005). In logistic regression TT was related to pre-operative ED (p = 0.010) and FT was related to post-operative ED (p = 0.001). CONCLUSION: Low FT value before radical prostatectomy was related to adverse pathological outcomes, biochemical recurrence and post-operative ED.


Assuntos
Disfunção Erétil/diagnóstico , Complicações Pós-Operatórias/diagnóstico , Prostatectomia/métodos , Neoplasias da Próstata/sangue , Neoplasias da Próstata/cirurgia , Testosterona/sangue , Fatores Etários , Idoso , Disfunção Erétil/sangue , Disfunção Erétil/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Complicações Pós-Operatórias/sangue , Complicações Pós-Operatórias/etiologia , Período Pré-Operatório , Prostatectomia/efeitos adversos , Neoplasias da Próstata/patologia , Estudos Retrospectivos , Fatores de Risco
11.
Neural Plast ; 2019: 9408612, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31885539

RESUMO

Objective: This study is aimed at investigating the characteristics of the spontaneous brain activity in inactive patients with nonneuropsychiatric systemic lupus erythematosus (non-NPSLE). Methods: Thirty-one female inactive patients with non-NPSLE and twenty healthy controls were examined by resting-state functional magnetic resonance imaging (RS-fMRI). Three amplitude methods including amplitude of low-frequency fluctuations (ALFF), fractional amplitude of low-frequency fluctuations (fALFF), and percent amplitude of fluctuation (PerAF) (with and without standardization) were applied to evaluate the spontaneous brain activity. The correlation was performed between low-frequency oscillations and clinical and neuropsychological factors in inactive patients with non-NPSLE. Results: Compared to healthy controls, patients with non-NPSLE showed increased standardized ALFF (mALFF) in the left inferior temporal gyrus and left putamen, decreased PerAF in the right postcentral gyrus and bilateral precentral gyrus, and increased standardized PerAF (mPerAF) in the left putamen and decreased mPerAF in the right postcentral gyrus and bilateral precentral gyrus. By standardized fALFF (mfALFF), no significant brain regions were found between the two groups. Correlation analysis revealed significantly positive correlations between glucocorticoid dose and PerAF in the right precentral gyrus and mPerAF in the left putamen, and Complement 3 (C3) and mPerAF in the right postcentral gyrus. There was a significant negative correlation between C3 and mALFF in the left putamen. Conclusion: Abnormal low-frequency oscillations in multiple brain regions were found in inactive patients with non-NPSLE, indicating that the alteration of mALFF, PerAF, and mPerAF in specific brain regions might be an imaging biomarker of brain dysfunction in inactive patients with non-NPSLE.


Assuntos
Encéfalo/diagnóstico por imagem , Progressão da Doença , Lúpus Eritematoso Sistêmico/diagnóstico por imagem , Lúpus Eritematoso Sistêmico/psicologia , Imageamento por Ressonância Magnética/métodos , Adulto , Encéfalo/fisiopatologia , Feminino , Humanos , Lúpus Eritematoso Sistêmico/fisiopatologia , Masculino
12.
Opt Express ; 25(5): 5352-5365, 2017 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-28380797

RESUMO

A novel fiber structure, coreless side-polished fiber (CSPF), is proposed and investigated to implement multimode interference (MMI) and high sensitive refractive index (RI) sensors. For such CSPF, the part of the cladding and the core of a single-mode fiber are side-polished off so as to make the remained cladding a D-shaped multimode waveguide. The excitation and evolution of MMI in the CSPF are simulated numerically. The simulation results show that the high-order modes excited within the D-shaped multimode waveguide are mainly TE0,1 (TM0,1)~TE0,6 (TM0,6) modes. Moreover, the RI sensing characteristics and the influences of residual thickness and dip wavelength on the sensitivity are investigated both numerically and experimentally. The experimental results show that the CSPF with a residual thickness of 43.1 µm can reach an ultra-high sensitivity of 28000 nm/RIU in the RI range of 1.442~1.444. It is also found that the sensitivity can be further increased by reducing the residual thickness and choosing the dip at a longer wavelength. Thanks to the ultra-high RI sensitivity and the ease of fabrication, the CSPF could provide a cost-effective platform to build high-performance fiber devices of various functions.

13.
Nanomaterials (Basel) ; 14(11)2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38869582

RESUMO

The emergence of antibiotic-resistant bacteria necessitates the development of novel, sustainable, and biocompatible antibacterial agents. This study addresses cytotoxicity and environmental concerns associated with traditional silver nanoparticles (AgNPs) by exploring lignin, a readily available and renewable biopolymer, as a platform for AgNPs. We present a novel one-pot synthesis method for lignin-based AgNPs (AgNPs@AL) nanocomposites, achieving rapid synthesis within 5 min. This method utilizes various organic solvents, demonstrating remarkable adaptability to a wide range of lignin-dissolving systems. Characterization reveals uniform AgNP size distribution and morphology influenced by the chosen solvent. This adaptability suggests the potential for incorporating lignin-loaded antibacterial drugs alongside AgNPs, enabling combined therapy in a single nanocomposite. Antibacterial assays demonstrate exceptional efficacy against both Gram-negative and Gram-positive bacteria, with gamma-valerolactone (GVL)-assisted synthesized AgNPs exhibiting the most potent effect. Mechanistic studies suggest a combination of factors contributes to the antibacterial activity, including direct membrane damage caused by AgNPs and sustained silver ion release, ultimately leading to bacterial cell death. This work presents a straightforward, adaptable, and rapid approach for synthesizing biocompatible AgNPs@AL nanocomposites with outstanding antibacterial activity. These findings offer a promising and sustainable alternative to traditional antibiotics, contributing to the fight against antibiotic resistance while minimizing environmental impact.

14.
Nanomaterials (Basel) ; 14(7)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38607127

RESUMO

This study employs a combined computational and experimental approach to elucidate the mechanisms governing the interaction between lignin and urea, impacting lignin dissolution and subsequent aggregation behavior. Molecular dynamics (MD) simulations reveal how the urea concentration and temperature influence lignin conformation and interactions. Higher urea concentrations and temperatures promote lignin dispersion by disrupting intramolecular interactions and enhancing solvation. Density functional theory (DFT) calculations quantitatively assess the interaction energy between lignin and urea, supporting the findings from MD simulations. Anti-solvent precipitation demonstrates that increasing the urea concentration hinders the self-assembly of lignin nanoclusters. The findings provide valuable insights for optimizing lignin biorefinery processes by tailoring the urea concentration and temperature for efficient extraction and dispersion. Understanding the influence of urea on lignin behavior opens up avenues for designing novel lignin-based materials with tailored properties. This study highlights the potential for the synergetic application of MD simulations and DFT calculations to unravel complex material interactions at the atomic level.

15.
Front Public Health ; 12: 1364735, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38873319

RESUMO

Introduction: Osteoporosis is a prevalent challenge in clinical orthopedics, affecting a significant percentage of individuals aged 50 and above. The goal of this study was to comprehensively understand the relationships between a specialized dietary regimen and the risk of developing osteoporosis. Methods: This study employed extensive genome-wide association study (GWAS) summary statistics derived from the UK Biobank. It encompassed 8 kinds of special diets and 7 datasets pertaining to osteoporosis and associated symptoms. The principal analytical approach employed was the inverse-variance weighted method. Additionally, sensitivity analysis was employed to elucidate the diverse multiplicity patterns observed in the final model. Results: Our results showed that there is significant evidence that a gluten-free diet is associated with osteoporosis [odds ratio (OR): 1.080, 95% confidence interval (CI): 1.048-1.112, p = 4.23E-07)]. Furthermore, there exists a suggestive link between the three distinct dietary approaches and osteoporosis [(OR: 0.949, 95%CI: 0.929-0.970, p = 3.00E-06) for comprehensive consumption; (OR: 1.053, 95%CI: 1.018-1.089, p = 2.23E-03) for abstaining from wheat consumption; (OR: 1.036, 95%CI: 1.005-1.068, p = 1.97E-02) for abstaining from sugar consumption]. No additional correlation between the special dietary regimens and osteoporosis has been observed. Conclusion: Our research has uncovered a notable correlation between a gluten-free diet and the occurrence of osteoporosis. Furthermore, it exerts a promoting influence on the onset of osteoporosis, which stands in direct contradiction to the therapeutic principles for Celiac Disease's complications. As such, a novel association among these three elements is postulated.


Assuntos
Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Osteoporose , Humanos , Osteoporose/epidemiologia , Reino Unido/epidemiologia , Incidência , Feminino , Masculino , Pessoa de Meia-Idade , Dieta Livre de Glúten/estatística & dados numéricos , Fatores de Risco , Idoso , Dieta/estatística & dados numéricos
16.
ACS Nano ; 18(4): 3763-3774, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38235647

RESUMO

Zinc sulfide is a promising high-capacity anode for practical sodium-ion batteries, considering its high capacity and the low cost of zinc and sulfur sources. However, the pulverization of particulate zinc sulfide causes active mass collapse and penetration-induced short circuits of batteries. Herein, a zinc sulfide encapsulated in a nitrogen-doped carbon shell (ZnS@NC) was developed for high-performance anodes. The confinement effect of nitrogen-doped carbon stabilizes the active mass structure during cycling thanks to the robust chemically and electronically bonded connections between nitrogen-doped carbon and zinc sulfide nanoparticles. Furthermore, the cycling stability of the ZnS@NC anode is boosted by the robust inorganic-rich solid electrolyte interphase (SEI) formed in cyclic and linear ether-based electrolytes. The ZnS@NC anode displayed a reversible specific capacity of 584 mAh g-1, an excellent rate capability of 327 mAh g-1 at 70 A g-1, and a highly stable cycling performance over 10000 cycles. This work provides a practical and promising approach to designing stable conversion anodes for high-performance sodium-ion batteries.

17.
Int J Biol Macromol ; 274(Pt 2): 133186, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38885858

RESUMO

Ligand-receptor recognition serves as the fundamental driving force for active targeting, yet it is still constrained by off-target effects. Herein, we demonstrate that circumventing or blocking the mononuclear phagocyte system (MPS) are both viable strategies to address off-target effects. Naturally derived lignin nanoparticles (LNPs) show great potential to block MPS due to its good stability, low toxicity, and degradability. We further demonstrate the impact of LNPs dosage on in vivo tumor targeting and antitumor efficacy. Our results show that a high dose of LNPs (300 mg/kg) leads to significant accumulation at the tumor site for a duration of 14 days after intravenous administration. In contrast, the low-dose counterparts (e.g., 50, 150 mg/kg) result in almost all LNPs accumulating in the liver. This discovery indicates that the liver is the primary site of LNP capture, leaving only the surplus LNPs the chance to reach the tumor. In addition, although cell membrane-engineered LNPs can rapidly penetrate tumors, they are still prone to capture by the liver during subsequent circulation in the bloodstream. Excitingly, comparable therapeutic efficacy is obtained for the above two strategies. Our findings may offer valuable insights into the targeted delivery of drugs for disease treatment.

18.
World J Clin Cases ; 11(22): 5351-5357, 2023 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-37621599

RESUMO

BACKGROUND: Anti-melanoma differentiation-associated gene 5 antibody-positive (anti-MDA5 Ab+) dermatomyositis complicated with rapidly progressive interstitial lung disease (anti-MDA5 Ab+ DM-RP-ILD) has an unclear underlying mechanism with no recommended unified treatment plan. Herein, one of the cases that we report (Case 2) was successfully treated with tocilizumab despite having lung infection. CASE SUMMARY: Case 1 was a 30-year-old woman who was admitted due to recurrent rash for 5 mo, fever and cough for 1 mo, and chest tightness for 3 d. She was diagnosed with non-myopathic dermatomyositis (anti-MDA5 Ab+) and interstitial pneumonia, and was treated with the combination of hormone therapy and cyclophosphamide followed by oral tacrolimus. Case 2 was a 31-year-old man admitted due to systemic rash accompanied by muscle weakness of limbs for more than 1 mo, and chest tightness and dry cough for 4 d. He was diagnosed with dermatomyositis (anti-MDA5 Ab+) and acute interstitial pneumonia with Pneumocystis jirovecii and Aspergillus fumigatus infections and was treated with hormone therapy (without cyclophosphamide) and the combination of tocilizumab and tacrolimus. The condition of both patients eventually improved and they were discharged and showed clinically stable condition at the latest follow-up. CONCLUSION: Tocilizumab could be a salvage treatment for patients with anti-MDA5 Ab+ DM-RP-ILD who are refractory to intensive immunosuppression.

19.
IEEE Trans Neural Netw Learn Syst ; 34(9): 5897-5910, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34890344

RESUMO

This study is concerned with the adaptive neural network (NN) observer design problem for continuous-time switched systems via quantized output signals. A novel NN observer is presented in which the adaptive laws are constructed using quantized measurements. Then, persistent dwell time (PDT) switching is considered in the observer design to describe fast and slow switching in a unified framework. Accurate estimations of state and actuator efficiency factor can be obtained by the proposed observer technique despite actuator degradation. Finally, a simulation example is provided to illustrate the effectiveness of the developed NN observer design approach.

20.
IEEE Trans Cybern ; 53(8): 5048-5058, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35560089

RESUMO

This article investigates the fault estimation (FE) problem for a class of nonlinear systems via an adaptive fuzzy approach. Considering the limited communication capacity of networks, the quantized measurement signals are used to construct adaptive laws instead of the real measurements in the designed fuzzy observer. By injecting the quantizer parameter into the observer inputs, the quantization effects on the convergence of estimation errors can be compensated. It is also shown that nondifferentiable actuator faults can be reconstructed by the developed FE approach. Finally, two simulation examples are provided to illustrate the validity of the presented scheme.

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