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1.
Chemosphere ; 349: 140873, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38056712

RESUMO

New alternatives for effluent decontamination, such as electrochemical oxidation, are being developed to provide adequate removal of endocrine disruptors such as 17ß-estradiol in wastewater. In this study, data-driven models of response surface methodology, artificial neural networks, wavelet neural networks, and adaptive neuro-fuzzy inference system will be used to predict the degradation and mineralization of the microcontaminant hormone 17ß-estradiol through an electrochemical process to contribute to the treatment of effluent containing urine. With the use of different statistical criteria and graphical analysis of the correlation between observed and predicted data, it was possible to conduct a comparative analysis of the performances of the data-driven approaches. The results point to the superiority of the adaptive neuro-fuzzy inference system (correlation coefficient, R2, ranged from 0.99330 to 0.99682 for TOC removal and from 0.95330 to 0.99223 for the degradation of the hormone 17ß-estradiol) techniques over the others. The remaining results obtained with the other metrics are consistent with this analysis.


Assuntos
Lógica Fuzzy , Redes Neurais de Computação , Águas Residuárias , Oxirredução , Estradiol
2.
MethodsX ; 9: 101676, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35402169

RESUMO

This paper presents a method to estimate institutional environment indexes using fuzzy modeling. Because of the complexity of the subject, institution, elements associated with this thinking are difficult to measure and compare. In order to address this problem, this research presents how a fuzzy inference system works and how to create institutional indexes from it. While methods that analyze institutional environments generally use secondary data from countries or regions provided by international organizations, the illustrative case applied to aquaculture in Brazil demonstrates the effectiveness of using this method to generate indexes related to the subject from primary data collected at the firm level. Furthermore, the combined use of this method with others already used in the institutional literature can be valuable both for researchers and public policy makers who seek to increasingly understand the role of institutions in economic performance.•Uses a Mamdani expert system of MIMO type to estimate institutional indexes.•Institutional ambient scores related to tilapia production in Brazil are presented.•The combined use of the method with others can be valuable for the research field.

3.
Comput Biol Med ; 140: 105059, 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34847385

RESUMO

One of the most characteristic signs of Parkinson's disease (PD) is hand tremor. The MDS-UPDRS scale evaluates different aspects of the disease. The tremor score is a part of the MDS-UPDRS scale, which provides instructions for rating it, by observation, with an integer from 0 to 4. Nevertheless, this form of assessment is subjective and dependent on visual acuity, clinical judgment, and even the mood of the individual examiner. On the other hand, in many cases, existing computational models proposed to resolve the disadvantages of the MDS-UPDRS scale may have uncertainty in differentiating a category of a slight Parkinson tremor from voluntary movements. In this study, 554 measurements from Parkinson's patients, and 60 measurements from healthy subjects, were recorded with inertial sensors placed on the back of each hand. Five biomechanical indicators characterised the hand tremor. With these indicators, the three fuzzy inference models proposed can differentiate, in the first instance, the presence of postural or resting tremor from a normal movement of the hand, and if detected, to determine its severity. The fuzzy inference models allowed following the criteria of the MDS-UPDRS scale, providing an evaluation with an accuracy of two decimal digits and which, due to its simplicity, can be implemented in clinical environments. The assessments of three experts validated the computer model.

4.
Sensors (Basel) ; 20(15)2020 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-32717787

RESUMO

The adequate automatic detection of driver fatigue is a very valuable approach for the prevention of traffic accidents. Devices that can determine drowsiness conditions accurately must inherently be portable, adaptable to different vehicles and drivers, and robust to conditions such as illumination changes or visual occlusion. With the advent of a new generation of computationally powerful embedded systems such as the Raspberry Pi, a new category of real-time and low-cost portable drowsiness detection systems could become standard tools. Usually, the proposed solutions using this platform are limited to the definition of thresholds for some defined drowsiness indicator or the application of computationally expensive classification models that limits their use in real-time. In this research, we propose the development of a new portable, low-cost, accurate, and robust drowsiness recognition device. The proposed device combines complementary drowsiness measures derived from a temporal window of eyes (PERCLOS, ECD) and mouth (AOT) states through a fuzzy inference system deployed in a Raspberry Pi with the capability of real-time response. The system provides three degrees of drowsiness (Low-Normal State, Medium-Drowsy State, and High-Severe Drowsiness State), and was assessed in terms of its computational performance and efficiency, resulting in a significant accuracy of 95.5% in state recognition that demonstrates the feasibility of the approach.


Assuntos
Condução de Veículo , Acidentes de Trânsito/prevenção & controle , Fadiga , Humanos , Iluminação , Fases do Sono , Vigília
5.
Front Robot AI ; 5: 31, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-33500917

RESUMO

This paper studies the issue of uncertainty in the ambulance location problem to cover the maximum number of demand points in a city. The work is based on the double standard model (DSM), a popular coverage model where two radii are considered to cover a percentage of the demand points twice. Uncertainty is introduced in the expected travel time between an ambulance and a demand point, before computing the optimal placement of ambulances in potential bases by solving the linear program posed by the DSM. The following three approaches are considered: (1) solving the DSM without uncertainty; (2) uncertainty in the travel time is based on triangular fuzzy set; and (3) a fuzzy inference system (FIS) with a rule base derived from the problem properties, which is the main contribution of this work. Results show that considering uncertainty can have a significant effect on the solutions for the DSM, with the solutions produced with the FIS approach achieving a higher total coverage of the demand. In conclusion, the proposed strategy could provide a reliable and effective tool to support decision making in the ambulance location problem by considering uncertainty in the ambulance travel times.

6.
Sensors (Basel) ; 15(12): 30142-64, 2015 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-26633417

RESUMO

The increasing use of mobile devices in indoor spaces brings challenges to location methods. This work presents a hybrid intelligent method based on data mining and Type-2 fuzzy logic to locate mobile devices in an indoor space by zones using Wi-Fi signals from selected access points (APs). This approach takes advantage of wireless local area networks (WLANs) over other types of architectures and implements the complete method in a mobile application using the developed tools. Besides, the proposed approach is validated by experimental data obtained from case studies and the cross-validation technique. For the purpose of generating the fuzzy rules that conform to the Takagi-Sugeno fuzzy system structure, a semi-supervised data mining technique called subtractive clustering is used. This algorithm finds centers of clusters from the radius map given by the collected signals from APs. Measurements of Wi-Fi signals can be noisy due to several factors mentioned in this work, so this method proposed the use of Type-2 fuzzy logic for modeling and dealing with such uncertain information.

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