Rommel Stiward Prieto, Diego Alberto Bravo Montenegro and Carlos Rengifo
The purpose of this paper is to approach predictive maintenance (PdM) of brushless direct current (BLDC) motors using audio signal processing and extracting statistical and…
Abstract
Purpose
The purpose of this paper is to approach predictive maintenance (PdM) of brushless direct current (BLDC) motors using audio signal processing and extracting statistical and spectral features to train classical machine learning (ML) models.
Design/methodology/approach
The proposed methodology relies on classification predictive model that shows the motors prone to failure. To verify this, the model was implemented and tested with audio data. The trained models are then deployed to an Industrial Internet of Things (IIoT) application built using Django.
Findings
The implementation of the methodology allows for achieving performance as high as 92% accuracy, proving that spectral features should be considered when training ML models for PdM.
Originality/value
The proposed model is an effective decision-making tool that provides an ideal solution for preventive maintenance scheduling problems for BLDC motors.
Details
Keywords
Exio Chaparro‐Martinez and Miguel Ángel Marzal
The purpose of this paper is to analyze the bibliographic references contained in the scientific papers (articles and technical notes) published from 1985 to 2005 in Zootecnia…
Abstract
Purpose
The purpose of this paper is to analyze the bibliographic references contained in the scientific papers (articles and technical notes) published from 1985 to 2005 in Zootecnia Tropical (ZT), a scientific journal.
Design/methodology/approach
A retrospective descriptive study is conducted using one‐dimensional bibliometric indicators such as: output, bibliographic density, institutional affiliation, recentness of the documents cited, document typology, self‐citations and scientific collaboration. Univariate descriptive analysis is used to study the indicators.
Findings
A total of 349 scientific papers (300 articles and 49 technical notes) are reviewed; output ranged from a maximum of 34 papers in 2001 to a minimum of four in 1990, with a mean of 15 papers per volume. The papers analyzed contain a total of 5,651 bibliographic references, with an average of 19 ± 9 references per paper; the largest number of references (19 ± 33) are found in the articles and the smallest (10.5 ± 13) in the notes. Venezuelan institutions account for 89 per cent of the papers and international institutions for the remain in 11 per cent; of the Venezuelan institutions, most (62 per cent) are National Institute of Agricultural Research (INIA) bodies and the rest universities and other organizations, especially the Universidad Central de Venezuela (UCV) and Universidad de Oriente (UDO). Universities are also among the most frequent international contributors, most prominently Marianga State University in Brazil and Tucumán National University in Argentina. Around 60 per cent of the references were more than ten years old when they were cited; 21 per cent were between five and ten years old and 19 per cent less than five years old. Journal articles, with 57 per cent, are the document type most frequently cited, followed by books, with 23 per cent; the rest consisted in postgraduate theses (3 per cent), undergraduate theses (2 per cent) and congress, conference and seminar proceedings (12 per cent). The self‐citation or endogamy rate in the journal is 4 per cent. Over half (53 per cent) of the papers are written by authors with the same affiliation. Inter‐institutional papers account for the remaining 47 per cent, with 34 per cent involving national collaboration, particularly between the INIA and the UCV; international co‐authorship comes to 13 per cent, primarily involving Brazilian and Argentine universities.
Originality/value
This paper analyzes the use of information in the Venezuelan scientific community from the vantage of a specific journal, ZT. These studies constitute useful and objective tools for evaluating scientific activity.
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Keywords
Juan Carlos Aguirre, Marco Leonardo Peralta Zuñiga, Pedro Mora and Francisco Blanco
This article is based on the assumption that entrepreneurship improves quality of life (HDI). Its main objective is to establish causal relationships between entrepreneurship…
Abstract
Purpose
This article is based on the assumption that entrepreneurship improves quality of life (HDI). Its main objective is to establish causal relationships between entrepreneurship variables such as credits, innovation (R&D), business growth, foreign direct investment and the Global Competitiveness Index and how these have influenced a country's development.
Design/methodology/approach
To analyse and validate this assumption, relevant information has been extracted about Ecuador (the subject of the study) for the 1998–2017 period. The information has received the respective econometric treatment, through a multivariate estimation by the autoregressive vector (ARV) method that made it possible to establish impulse-response functions.
Results
The results indicate that there is a significant and positive statistical impact between the variables related to entrepreneurship and quality of life (HDI), with the exception of “Innovation”, which is not representative in the model, demonstrating that the investment made at country level in R&D is not sufficient to have an impact on the HDI. It was also determined that promoting entrepreneurship would be useful as this would alter the trend of the variables, making them conducive to increasing the HDI.
Originality/value
This article is one of the few to address this issue. It includes the self-regressive vector model as a key methodology used to evaluate and establish public policies. RVM has provided positive results in the field of economics and can be adopted in the area of entrepreneurship.
Propósito
El presente artículo se basa en el supuesto de que el emprendimiento mejora la calidad de vida de los individuos (IDH), siendo el objetivo principal establecer relaciones causales entre variables de emprendimiento como: Créditos, Innovación (I + D), Crecimiento Empresarial, Inversión Extranjera Directa e Índice de Competitividad Global; y, como estas han influido en el desarrollo de un país.
Diseño/metodología/enfoque
Para el análisis y validación del supuesto mencionado anteriormente, se ha extraído información relevante sobre el Ecuador (sujeto de estudio) para el período comprendido entre 1998 y 2017, a los cuales se les ha dado el respectivo tratamiento econométrico, a través de una estimación multivariante por el método de Vectores Autorregresivos (VAR) que permitió establecer funciones de impulso – respuesta.
Resultados
Los resultados señalan que existe una significativa incidencia estadística entre las variables relacionadas con el emprendimiento y la calidad de vida (IDH) de manera positiva, a excepción de la “Innovación” que no tiene representatividad en el modelo, demostrando que la inversión realizada a nivel país en I + D es insuficiente para impactar el IDH. También se determinó la conveniencia de impulsar el emprendimiento, pues esto cambia la tendencia de las variables haciéndolas favorables para el crecimiento del IDH.
Originalidad/valor
Este artículo es uno de los pocos en abordar esta problemática, además incluye el Modelo de Vectores Autorregresivos como una metodología clave para evaluar y establecer políticas públicas, que ha brindado resultados positivos en el campo de la Economía y que puede adoptarse en la rama del Emprendimiento.