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1.
Sensors (Basel) ; 24(6)2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38544057

RESUMO

An accurate calculation of the indicator diagram of a pumping unit is the key factor in analyzing the performance of an oilfield production and operation and in preparing and optimizing an oilfield development plan. Aiming at the problems of the poor stability of the conventional load-displacement sensor method and the wave equation method, owing to the influence of an alternating load on the force sensor and the difficulty in measuring the crank angle using the electrical parameter method, a new soft sensing method employing the input electrical parameters of the motor and the beam inclination has been proposed to obtain the indicator diagram. At first, this method is established based on the beam angle of the pumping unit, which is easily measured using the suspension point displacement mathematics calculation model and the torque factor. Subsequently, the electric motor input parameters, the parameters of the four-bar linkage, and the relationship between the polished rod load have been established. Finally, the motor and the beam angle of the measured electrical parameters have been substituted into the calculation of the suspension point displacement and load value and pull in accordance with the guidelines to eliminate the singularity mutation values. After processing the measured data through a Butterworth filter, the indicator diagram is obtained. The results of the engineering experiment and application show that the average relative error of the method is less than 3.95%, and the maximum relative error remains within 2% for 6 months, which verifies the stability of the soft sensing method.

2.
Medicine (Baltimore) ; 101(45): e31662, 2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36397443

RESUMO

Management of patients with chronic diseases in rural areas and the use of medications need to be urgently addressed. Therefore, this study aimed to evaluate the efficacy of a family-involved smart medication management system for rural patients with chronic diseases. Between June and August 2021, 82 patients with chronic diseases were selected using convenience sampling from 2 county towns in Hebei Province, China. They were randomly divided into control (41 participants) and experimental (41 participants) groups. The control group was managed using a routine medication management model for chronic diseases. The experimental group was managed using a family-involved smart medication management system, in addition to the control group interventions. The groups were graded using the 8-item Morisky Medication Adherence Scale (MMAS-8), the Self-efficacy for Appropriate Medication Use Scale (SEAMS), the Medication Knowledge Assessment Questionnaire, and the Family Support Scale before the intervention and at 8 and 24 weeks after the intervention. Pre-intervention group differences were not statistically significant. At 8 weeks after the intervention, the control group showed no statistically significant differences in the MMAS-8, SEAMS, and Medication Knowledge Assessment scores pre-and post-intervention. These scores were higher in the experimental group than in the control group, with the post-intervention scores being higher than the pre-intervention scores. The MMAS-8, SEAMS, and Medication Knowledge Assessment scores for the experimental group were higher at 24 weeks than at 8 weeks; these scores were higher in the experimental group than in the control group. The experimental group also had higher family support scores than the control group; these scores were higher pre-intervention than post-intervention. A family-involved smart medication management system can effectively improve medication adherence, self-efficacy for appropriate medication use, medication knowledge assessment scores, and family support for rural middle-aged and older adult patients with chronic diseases.


Assuntos
Conduta do Tratamento Medicamentoso , População Rural , Pessoa de Meia-Idade , Humanos , Idoso , Adesão à Medicação , Inquéritos e Questionários , Doença Crônica
3.
PLoS One ; 16(6): e0252619, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34061909

RESUMO

In view of the development direction of high power and miniaturization of high-voltage power supply, higher requirements are put forward for the breakdown strength, thermal conductivity of packaging materials for its high voltage output module. An electric-insulated heat-conducted material with aluminium nitride as heat conducting filler and addition-cure liquid silicone rubber (ALSR) as matrix for high voltage power encapsulation has been studied. Initially, the thermal conductivity and breakdown strength of composites were explored at different filler fractions. With increase of filler fraction, the thermal conductivity increased and the breakdown strength decreased. Then, with the packaging module volume as the optimization objective and the working temperature as the optimization condition, the temperature distribution of high voltage power supply was studied by using the finite element method, and 40wt% filling fraction was selected as the optimal ratio. Finally, the actual packaging experiment of the high voltage module is carried out. and the variation of the output voltage and temperature with the working time is obtained. According to the experimental results, the output voltage of the high voltage module is basically stable, and the maximum surface temperature is 40.4°C. The practicability of the electric-insulated heat-conducted material has been proved.


Assuntos
Compostos de Alumínio/química , Resinas Compostas/química , Eletricidade , Elastômeros de Silicone/química , Dimetilpolisiloxanos/química , Análise de Elementos Finitos , Temperatura , Condutividade Térmica
4.
RSC Adv ; 9(49): 28851-28856, 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-35529667

RESUMO

The present work aims at studying the thermal and dielectric properties of addition-cure liquid silicone rubber (ALSR) matrix composites using boron nitride (BN) and aluminum nitride (AlN) as a hybrid thermal conductive filler. Composite samples with different filler contents were fabricated, and the density, thermal conductivity, thermal stability, dielectric properties, and volume resistivity of the samples were measured. According to the experimental results, the density, thermal conductivity, dielectric constant and dielectric loss tangent values all increased with the increasing addition of filler. When the weight fraction of hBN filler was 50 wt%, the thermal conductivity of composites was 0.554 W (m-1 K-1), which is 3.4 times higher than that of pure ALSR. The corresponding relative permittivity and dielectric loss were 3.98 and 0.0085 at 1 MHz, respectively. Furthermore, TGA results revealed that the AlN/BN hybrid filler could also improve the thermal stability of ALSR. The volume resistivity of ALSR composites was higher than that of pure ALSR. The addition of fillers improved the thermal properties of ALSR and had little effect on its insulation properties. This characteristic makes ALSR composites attractive in the field of insulating materials.

5.
Genesis ; 51(5): 357-64, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23097340

RESUMO

Salmonella enterica serovar enteritidis is an enteric bacterium that can contaminate chicken eggs and meat, resulting in production losses and consumer illness. To provide insight into the systemic metabolic effects of S. enteritidis infection, liver samples were harvested 10-days postinfection from broiler hens. Hepatic global gene expression levels were assessed using a chicken 44K Agilent microarray. Forty-four genes were differentially expressed at a significance level of q value < 0.05. One hundred eighty-three genes were differentially expressed at a suggestive significance level of q value < 0.1. A predominance of downregulation existed among significantly differentially expressed genes. Cell cycle and metabolism networks were created from the differentially expressed genes. Mitochondria-mediated apoptosis, electron transport, peptidase activity, vein constriction, cell differentiation, IL-2 signaling, Jak-Stat signaling, B-cell receptor signaling, GDP/GTP exchange, and protein recycling were among the functions of the differentially expressed genes that were down-regulated in response to S. enteritidis. The effects of S. enteritidis infection on the liver transcriptome profiles of broilers reflect a predominance of downregulation of genes with cell cycle and metabolic functions. The most pronounced response was the downregulation of genes that function in metabolic pathways, inflammation, and mitochondria-mediated apoptosis. These results provide insight into important systemic metabolic mechanisms that are active in the chicken liver in response to S. enteritidis infection at 10-days postinfection.


Assuntos
Proteínas Aviárias/biossíntese , Galinhas/metabolismo , Fígado/metabolismo , Doenças das Aves Domésticas/metabolismo , Salmonelose Animal/metabolismo , Salmonella enteritidis , Transcriptoma , Animais , Feminino , Regulação da Expressão Gênica , Fígado/patologia , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/patologia , Salmonelose Animal/patologia
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