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1.
Sensors (Basel) ; 21(13)2021 Jul 02.
Article in English | MEDLINE | ID: mdl-34283092

ABSTRACT

In sucker-rod pumping wells, due to the lack of an early diagnosis of operating condition or sensor faults, several problems can go unnoticed. These problems can increase downtime and production loss. In these wells, the diagnosis of operation conditions is carried out through downhole dynamometer cards, via pre-established patterns, with human visual effort in the operation centers. Starting with machine learning algorithms, several papers have been published on the subject, but it is still common to have doubts concerning the difficulty level of the dynamometer card classification task and best practices for solving the problem. In the search for answers to these questions, this work carried out sixty tests with more than 50,000 dynamometer cards from 38 wells in the Mossoró, RN, Brazil. In addition, it presented test results for three algorithms (decision tree, random forest and XGBoost), three descriptors (Fourier, wavelet and card load values), as well as pipelines provided by automated machine learning. Tests with and without the tuning of hypermeters, different levels of dataset balancing and various evaluation metrics were evaluated. The research shows that it is possible to detect sensor failures from dynamometer cards. Of the results that will be presented, 75% of the tests had an accuracy above 92% and the maximum accuracy was 99.84%.


Subject(s)
Algorithms , Machine Learning , Brazil , Humans
2.
Sensors (Basel) ; 21(3)2021 Jan 27.
Article in English | MEDLINE | ID: mdl-33514040

ABSTRACT

To satisfy the market, competition in the industrial sector aims for productivity and safety in industrial plant control systems. The appearance of a fault can compromise the system's proper functioning process. Therefore, Fault Detection and Diagnosis (FDD) methods contribute to avoiding any undesired events, as there are techniques and methods that study the detection, isolation, identification and, consequently, fault diagnosis. In this work, a new methodology that uses faults emulation to obtain parameters similar to the Development and Application of Methods for Diagnosis of Actuators in Industrial Control Systems (DAMADICS) benchmark model will be developed. This methodology uses previous information from tests on sensors with and without faults to detect and classify the situation of the plant and, in the presence of faults, perform the diagnosis through a process of elimination in a hierarchical manner. In this way, the definition of residue signature is used as well as the creation of a decision tree. The whole process is carried out incorporating FDD techniques, through the Non-Linear Auto-Regressive Neural Network Model With Exogenous Inputs (NARX), in the diagnosis of the behavioral prediction of the signals to generate the residual values. Then, it is applied to the construction of the decision tree based on the most significant residue of a certain signal, enabling the process of acquisition and formation of the signature matrix. With the procedures in this article, it is possible to demonstrate a practical and systematic method of how to emulate faults for control valves and the possibility of carrying out an analysis of the data to acquire signatures of the fault behavior. Finally, simulations resulting from the most sensitized variables for the production of residuals that is generated by neural networks are presented, which are used to obtain signatures and isolate the flaws. The process proves to be efficient in computational time and makes it easy to present a fault diagnosis strategy that can be reproduced in other processes.

3.
Sensors (Basel) ; 18(9)2018 Sep 13.
Article in English | MEDLINE | ID: mdl-30216994

ABSTRACT

Industrial pipelines must be inspected to detect typical failures, such as obstructions and deformations, during their lifetime. In the petroleum industry, the most used non-destructive technique to inspect buried pipelines is pigging. This technique consists of launching a Pipeline Inspection Gauge (PIG) inside the pipeline, which is driven by the pressure differential produced by fluid flow. The purpose of this work is to study the application of artificial neural networks to calculate the PIG's velocity based on the pressure differential. We launch a prototype PIG inside a testing pipeline, where this PIG gathers velocity data from an odometer-based system, while a supervisory system gathers pressure data from the testing pipeline. Then we train a Multilayer Perceptron (MLP) and a Nonlinear Autoregressive Network with eXogenous Inputs (NARX) network with the gathered data to predict velocity. The results suggest it is possible to use a neural network to model the PIG's velocity from pressure differential measurements. Our method is a new approach to the typical speed measurements based only on odometer, since the odometer is prone to fail and present poor results under some circumstances. Moreover, it can be used to provide redundancy, improving reliability of data obtained during the test.

4.
Sensors (Basel) ; 17(9)2017 Sep 15.
Article in English | MEDLINE | ID: mdl-28914757

ABSTRACT

The pipeline inspection using a device called Pipeline Inspection Gauge (PIG) is safe and reliable when the PIG is at low speeds during inspection. We built a Testing Laboratory, containing a testing loop and supervisory system to study speed control techniques for PIGs. The objective of this work is to present and validate the Testing Laboratory, which will allow development of a speed controller for PIGs and solve an existing problem in the oil industry. The experimental methodology used throughout the project is also presented. We installed pressure transducers on pipeline outer walls to detect the PIG's movement and, with data from supervisory, calculated an average speed of 0.43 m/s. At the same time, the electronic board inside the PIG received data from odometer and calculated an average speed of 0.45 m/s. We found an error of 4.44%, which is experimentally acceptable. The results showed that it is possible to successfully build a Testing Laboratory to detect the PIG's passage and estimate its speed. The validation of the Testing Laboratory using data from the odometer and its auxiliary electronic was very successful. Lastly, we hope to develop more research in the oil industry area using this Testing Laboratory.

5.
Article in English | MEDLINE | ID: mdl-22254303

ABSTRACT

Some diseases, such as hypertension, require a close control of the patient's blood pressure. This is even more critical when that patient is going through--or has just underwent--a surgical procedure In such situations, reducing blood pressure to normal levels is of paramount importance. Usually, this demanding and time consuming monitoring is done manually by clinical personnel and are subject to mistakes and inconsistent practices. In this paper, we propose a solution to the manual monitoring through the design and implementation of an embedded PID controller to handle blood pressure, integrated to an automated monitoring system to assist in detecting anomalies and to optimize the process of patient care.


Subject(s)
Antihypertensive Agents/administration & dosage , Blood Pressure/drug effects , Drug Therapy, Computer-Assisted/methods , Hypertension/drug therapy , Hypertension/physiopathology , Models, Cardiovascular , Computer Simulation , Feedback, Physiological , Humans
6.
Article in English | MEDLINE | ID: mdl-21095690

ABSTRACT

The quick progress in technology has brought new paradigms to the computing area, bringing with them many benefits to society. The paradigm of ubiquitous computing brings innovations applying computing in people's daily life without being noticed. For this, it has used the combination of several existing technologies like wireless communications and sensors. Several of the benefits have reached the medical area, bringing new methods of surgery, appointments and examinations. This work presents telemedicine software that adds the idea of ubiquity to the medical area, innovating the relation between doctor and patient. It also brings security and confidence to a patient being monitored in homecare.


Subject(s)
Home Care Services , Monitoring, Ambulatory/instrumentation , Monitoring, Physiologic/methods , Algorithms , Appointments and Schedules , Computer Communication Networks , Computer Graphics , Equipment Design/instrumentation , Humans , Monitoring, Physiologic/instrumentation , Programming Languages , Software , Telemedicine/instrumentation , Telemedicine/methods , User-Computer Interface
7.
In. Schiabel, Homero; Slaets, Annie France Frère; Costa, Luciano da Fontoura; Baffa Filho, Oswaldo; Marques, Paulo Mazzoncini de Azevedo. Anais do III Fórum Nacional de Ciência e Tecnologia em Saúde. Säo Carlos, s.n, 1996. p.113-114, graf.
Monography in Portuguese | LILACS | ID: lil-236272

ABSTRACT

Este trabalho apresenta um método para o controle da pressão arterial usando vasodilatadores como o nitropussiato de sódio (NPS). Para este propósito, um controlador adaptativo baseado em uma lei de controle de mínima variância é utilizado. O controlador é projetado para otimizar o desempenho do sistema em malha fechada levando em conta restrições clínicas impostas na taxa de infusão de NPS e na taxa de variação da pressão arterial. Simulação mostraram o bom desempenho do controlador proposto na presença de ruído.


Abstract - This paper presents an approach for adaptive control of blood pressure using vasodilators as sodium nitroprusside. For this purpose, an adaptive controller based upon a minimum variance law is used. The controller is proposed in order to optirnize the performance of the closed loop system while meeting clinicai constraints imposed on infusion rate and on rate of change of the patient's blood pressure. Computer simulations show the good performance ofthe proposed controller in the presence ofnoise.


Subject(s)
Humans , Nitroprusside/therapeutic use , Arterial Pressure , Vasodilator Agents/therapeutic use , Nitroprusside/adverse effects , Postoperative Complications
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