Hernán Alberto González

Hernán Alberto González

orcid

Research Focus & Metrics

Academic Career Length

21Years (2006-Present)

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

Representative Publications

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11 May 2020 in IEEE Access
Verified
Journal Article
Open access
JDJulian D. Loaiza Duque
Julian D. Loaiza Duque
Antonio J. Sánchez EgeaAntonio J. Sánchez Egea
Antonio J. Sánchez Egea
TRTheresa Reeb
Theresa Reeb
HGHernán Alberto González
Hernán Alberto González
AGAndres M. Gonzalez-Vargas
Andres M. Gonzalez-Vargas
Recent research has shown that smartphones/smartwatches have a high potential to help physicians to identify and differentiate between different movement disorders. This work aims to develop Machine Learning models to improve the differential diagnosis between patients with Parkinson’s Disease and Essential Tremor. For this purpose, we use a mobile phone’s built-in gyroscope to record the angular velocity signals of two different arm positions during the patient’s follow-up, more precisely, in rest and posture positions. To develop and to find the best classification models, diverse factors were considered, such as the frequency range, the training and testing divisions, the kinematic features, and the classification method. We performed a two-stage kinematic analysis, first to differentiate between healthy and trembling subjects and then between patients with Parkinson’s Disease and Essential Tremor. The models developed reached an average accuracy of 97.2±3.7% (98.5% Sensitivity, 93.3% Specificity) to differentiate between Healthy and Trembling subjects and an average accuracy of 77.8±9.9% (75.7% Sensitivity, 80.0% Specificity) to discriminate between Parkinson’s Disease and Essential Tremor patients. Therefore, we conclude, that the angular velocity signal can be used to develop Machine Learning models for the differential diagnosis of Parkinson’s disease and Essential Tremor.

12 March 2016 in The International Journal of Advanced Manufacturing Technology
Verified
Journal Article
Closed access
PDF file
SHSaqib Hameed
Saqib Hameed
HGHernán Alberto González
Hernán Alberto González
Antonio J. Sánchez EgeaAntonio J. Sánchez Egea
Antonio J. Sánchez Egea
AAAmelia Nápoles Alberro
Amelia Nápoles Alberro

25 May 2018 in Materials
Verified
Journal Article
Open access
PDF file
SHSaqib Hameed
Saqib Hameed
HGHernán Alberto González
Hernán Alberto González
JBJosé I. Perat Benavides
José I. Perat Benavides
AAAmelia Nápoles Alberro
Amelia Nápoles Alberro
Antonio J. Sánchez EgeaAntonio J. Sánchez Egea
Antonio J. Sánchez Egea
In this article, the influence of electropulsing on the machinability of steel S235 and aluminium 6060 has been studied during conventional and electropulsing-assisted turning processes. The machinability indices such as chip compression ratio ξ , shear plane angle ϕ and specific cutting energy (SCE) are investigated by using different cutting parameters such as cutting speed, cutting feed and depth of cut during electrically-assisted turning process. The results and analysis of this work indicated that the electrically-assisted turning process improves the machinability of steel S235, whereas the machinability of aluminium 6060 gets worse. Finally, due to electropluses (EPs), the chip compression ratio ξ increases with the increase in cutting speed during turning of aluminium 6060 and the SCE decreases during turning of steel S235.

21 September 2022 in Sensors
Verified
Journal Article
Open access
PDF file
MAMuhammad Rizwan Awan
Muhammad Rizwan Awan
HGHernán Alberto González
Hernán Alberto González
SHSaqib Hameed
Saqib Hameed
Fahid RiazFahid Riaz
Fahid Riaz
SHShahzaib Hamid
Shahzaib Hamid
AHAbrar Hussain
Abrar Hussain
Cut-off operation is widely used in the manufacturing industry and is highly energy-intensive. Prediction of specific energy consumption (SEC) using data-driven models is a promising means to understand, analyze and reduce energy consumption for cut-off grinding. The present article aims to put forth a novel methodology to predict and validate the specific energy consumption for cut-off grinding of oxygen-free copper (OFC–C10100) using supervised machine learning techniques. State-of-the-art experimental setup was designed to perform the abrasive cutting of the material at various cutting conditions. First, energy consumption values were predicted on the bases of input process parameters of feed rate, cutting thickness, and cutting tool type using the three supervised learning techniques of Gaussian process regression, regression trees, and artificial neural network (ANN). Among the three algorithms, Gaussian process regression performance was found to be superior, with minimum errors during validation and testing. The predicted values of energy consumption were then exploited to evaluate the specific energy consumption (SEC), which turned out to be highly accurate, with a correlation coefficient of 0.98. The relationship of the predicted specific energy consumption (SEC) with material removal rate agrees well with the relationship depicted in physical models, which further validates the accuracy of the prediction models.

21 March 2019 in Materials
Verified
Journal Article
Open access
PDF file
AAAmelia Nápoles Alberro
Amelia Nápoles Alberro
HGHernán Alberto González
Hernán Alberto González
Antonio J. Sánchez EgeaAntonio J. Sánchez Egea
Antonio J. Sánchez Egea
SHSaqib Hameed
Saqib Hameed
RAReyna M. Peña Aguilar
Reyna M. Peña Aguilar
Grinding energy efficiency depends on the appropriate selection of cutting conditions, grinding wheel, and workpiece material. Additionally, the estimation of specific energy consumption is a good indicator to control the consumed energy during the grinding process. Consequently, this study develops a model of material-removal rate to estimate specific energy consumption based on the measurement of active power consumed in a plane surface grinding of C45K with different thermal treatments and AISI 304. This model identifies and evaluates the dissipated power by sliding, ploughing, and chip formation in an industrial-scale grinding process. Furthermore, the instantaneous positions of abrasive grains during cutting are described to study the material-removal rate. The estimation of specific chip-formation energy is similar to that described by other authors on a laboratory scale, which allows to validate the model and experiments. Finally, the results show that the energy consumed by sliding is the main mechanism of energy dissipation in an industrial-scale grinding process, where it is denoted that sliding energy by volume unity decreases as the depth of cut and the speed of the workpiece increase.

18 September 2017 in Journal of Manufacturing Science and Engineering
Verified
Journal Article
Open access
PDF file
Antonio J. Sánchez EgeaAntonio J. Sánchez Egea
Antonio J. Sánchez Egea
HGHernán Alberto González
Hernán Alberto González
Diego CelentanoDiego Celentano
Diego Celentano
JPJordi Jorba Perió
Jordi Jorba Perió
JCJian Cao
Jian Cao
Electrically assisted (EA) wire drawing process is a hybrid manufacturing process characterized by enhancement of the formability, ductility, and elongation of the wire drawn specimen. A thermomechanical model to describe the change of the mechanical response due to the thermal contribution is proposed in this work. Additionally, a numerical simulation was conducted to study the potential and limitations of this hybrid process by using two different hardening laws: a phenomenological and a dislocation-based hardening laws. The results show how the flow stress, the effective plastic strain, and residual stresses behave under the electroplusing effect. In addition, electron backscattered diffraction was used to study the electropulsing treatments on the microstructure during cold drawing. It is observed a decrease of the high- and low-angle grain boundaries (LAGB) for samples deformed with electropulsing. This detwinning process has a strong influence on the strain hardening by improving the material formability. It was shown that the two proposed hardening laws adequately describe the EA wire drawing process showing a similar mechanical behavior. Nevertheless, the dislocation-based hardening law has the potential to be generalized to many other material and process configurations without extensive number of material tests as the phenomenological hardening law would require.