rafael magallanes-quintanar

Prof. rafael magallanes-quintanar

Universidad Autónoma de Zacatecas
orcid

Research Focus & Metrics

Academic Career Length

23Years (2004-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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12 February 2020 in Applied Sciences
Verified
Journal Article
Open access
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VMValeria Maeda-Gutiérrez
Valeria Maeda-Gutiérrez
Carlos Eric Galván-TejadaCarlos Eric Galván-Tejada
Carlos Eric Galván-Tejada
LZLaura Zanella
Laura Zanella
JPJose Maria Padilla
Jose Maria Padilla
Carlos Eric Galván-TejadaCarlos Eric Galván-Tejada
Carlos Eric Galván-Tejada
Carlos A. Olvera-OlveraCarlos A. Olvera-Olvera
Carlos A. Olvera-Olvera
Tomato plants are highly affected by diverse diseases. A timely and accurate diagnosis plays an important role to prevent the quality of crops. Recently, deep learning (DL), specifically convolutional neural networks (CNNs), have achieved extraordinary results in many applications, including the classification of plant diseases. This work focused on fine-tuning based on the comparison of the state-of-the-art architectures: AlexNet, GoogleNet, Inception V3, Residual Network (ResNet) 18, and ResNet 50. An evaluation of the comparison was finally performed. The dataset used for the experiments is contained by nine different classes of tomato diseases and a healthy class from PlantVillage. The models were evaluated through a multiclass statistical analysis based on accuracy, precision, sensitivity, specificity, F-Score, area under the curve (AUC), and receiving operating characteristic (ROC) curve. The results present significant values obtained by the GoogleNet technique, with 99.72% of AUC and 99.12% of sensitivity. It is possible to conclude that this significantly success rate makes the GoogleNet model a useful tool for farmers in helping to identify and protect tomatoes from the diseases mentioned.

10 January 2019 in Diagnostics
Verified
Journal Article
Open access
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LZLaura Zanella
Laura Zanella
Carlos Eric Galván-TejadaCarlos Eric Galván-Tejada
Carlos Eric Galván-Tejada
NCNubia M. Chávez-Lamas
Nubia M. Chávez-Lamas
MGM. del Carmen Gracia-Cortés
M. del Carmen Gracia-Cortés
rafael magallanes-quintanarrafael magallanes-quintanar
rafael magallanes-quintanar
HGHamurabi Gamboa
Hamurabi Gamboa
Depression is a mental disorder characterized by recurrent sadness and loss of interest in the enjoyment of the positive aspects of life, in addition to fatigue, causing inability to perform daily activities, which leads to a loss of quality of life. To monitor depression (unipolar and bipolar patients), traditional methods rely on reports from patients; nevertheless, bias is commonly present in them. To overcome this problem, Ecological Momentary Assessment (EMA) reports have been widely used, which include data of the behavior, feelings and other types of activities recorded almost in real time through the use of portable devices and smartphones containing motion sensors. In this work a methodology was proposed to detect depressive subjects from control subjects based in the data of their motor activity, recorded by a wearable device, obtained from the “Depresjon” database. From the motor activity signals, the extraction of statistical features was carried out to subsequently feed a random forest classifier. Results show a sensitivity value of 0.867, referring that those subjects with presence of depression have a degree of 86.7% of being correctly classified, while the specificity shows a value of 0.919, referring that those subjects with absence of depression have a degree of 91.9% of being classified with a correct response, using the motor activity signal provided from the wearable device. Based on these results, it is concluded that the motor activity allows distinguishing between the two classes, providing a preliminary and automated tool to specialists for the diagnosis of depression.

3 November 2010 in Journal of Plant Nutrition and Soil Science
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Journal Article
Closed access
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FBFidel Blanco‐Macías
Fidel Blanco‐Macías
rafael magallanes-quintanarrafael magallanes-quintanar
rafael magallanes-quintanar
RVRicardo David Valdez-Cepeda
Ricardo David Valdez-Cepeda
RVRigoberto Vázquez‐Alvarado
Rigoberto Vázquez‐Alvarado
EOEmilio Olivares‐Sáenz
Emilio Olivares‐Sáenz
BMBernardo Murillo‐Amador
Bernardo Murillo‐Amador

18 June 2018 in Bioengineering
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Journal Article
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LZLaura Zanella
Laura Zanella
Carlos Eric Galván-TejadaCarlos Eric Galván-Tejada
Carlos Eric Galván-Tejada
NCNubia M. Chávez-Lamas
Nubia M. Chávez-Lamas
JRJesús Rivas-Gutierrez
Jesús Rivas-Gutierrez
rafael magallanes-quintanarrafael magallanes-quintanar
rafael magallanes-quintanar
HGHamurabi Gamboa
Hamurabi Gamboa
Oral health represents an essential component in the quality of life of people, being a determinant factor in general health since it may affect the risk of suffering other conditions, such as chronic diseases. Oral diseases have become one of the main public health problems, where dental caries is the condition that most affects oral health worldwide, occurring in about 90% of the global population. This condition has been considered a challenge because of its high prevalence, besides being a chronic but preventable disease which can be caused depending on the consumption of certain nutritional elements interacting simultaneously with different factors, such as socioeconomic factors. Based on this problem, an analysis of a set of 189 dietary and demographic determinants is performed in this work, in order to find the relationship between these factors and the oral situation of a set of subjects. The oral situation refers to the presence and absence/restorations of caries. The methodology is performed constructing a dense artificial neural network (ANN), as a computer-aided diagnosis tool, looking for a generalized model that allows for classifying subjects. As validation, the classification model was evaluated through a statistical analysis based on a cross validation, calculating the accuracy, loss function, receiving operating characteristic (ROC) curve and area under the curve (AUC) parameters. The results obtained were statistically significant, obtaining an accuracy ≃ 0.69 and AUC values of 0.69 and 0.75. Based on these results, it is possible to conclude that the classification model developed through the deep ANN is able to classify subjects with absence of caries from subjects with presence or restorations with high accuracy, according to their demographic and dietary factors.

17 March 2020 in Diagnostics
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Journal Article
Open access
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JRJulieta G. Rodríguez-Ruiz
Julieta G. Rodríguez-Ruiz
Carlos Eric Galván-TejadaCarlos Eric Galván-Tejada
Carlos Eric Galván-Tejada
LZLaura Zanella
Laura Zanella
JPJose Maria Padilla
Jose Maria Padilla
Carlos Eric Galván-TejadaCarlos Eric Galván-Tejada
Carlos Eric Galván-Tejada
MSManuel A. Soto-Murillo
Manuel A. Soto-Murillo
Major Depression Disease has been increasing in the last few years, affecting around 7 percent of the world population, but nowadays techniques to diagnose it are outdated and inefficient. Motor activity data in the last decade is presented as a better way to diagnose, treat and monitor patients suffering from this illness, this is achieved through the use of machine learning algorithms. Disturbances in the circadian rhythm of mental illness patients increase the effectiveness of the data mining process. In this paper, a comparison of motor activity data from the night, day and full day is carried out through a data mining process using the Random Forest classifier to identified depressive and non-depressive episodes. Data from Depressjon dataset is split into three different subsets and 24 features in time and frequency domain are extracted to select the best model to be used in the classification of depression episodes. The results showed that the best dataset and model to realize the classification of depressive episodes is the night motor activity data with 99.37% of sensitivity and 99.91% of specificity.

23 November 2016 in Mobile Information Systems
Verified
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Carlos Eric Galván-TejadaCarlos Eric Galván-Tejada
Carlos Eric Galván-Tejada
JGJorge I. Galván-Tejada
Jorge I. Galván-Tejada
JPJose Maria Padilla
Jose Maria Padilla
JDJ. Rubén Delgado-Contreras
J. Rubén Delgado-Contreras
rafael magallanes-quintanarrafael magallanes-quintanar
rafael magallanes-quintanar
HGHamurabi Gamboa-Rosales
Hamurabi Gamboa-Rosales
This work presents a human activity recognition (HAR) model based on audio features. The use of sound as an information source for HAR models represents a challenge because sound wave analyses generate very large amounts of data. However, feature selection techniques may reduce the amount of data required to represent an audio signal sample. Some of the audio features that were analyzed include Mel-frequency cepstral coefficients (MFCC). Although MFCC are commonly used in voice and instrument recognition, their utility within HAR models is yet to be confirmed, and this work validates their usefulness. Additionally, statistical features were extracted from the audio samples to generate the proposed HAR model. The size of the information is necessary to conform a HAR model impact directly on the accuracy of the model. This problem also was tackled in the present work; our results indicate that we are capable of recognizing a human activity with an accuracy of 85% using the HAR model proposed. This means that minimum computational costs are needed, thus allowing portable devices to identify human activities using audio as an information source.