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Libros y autores contemporaneos (Ganivet, Unamuno, Ortega y Gasset, Azorin, Baroja, Valle-Inclan, A. Machado, Perez de Ayala)

Joaquin Ortega, Cesar Barja
1936 The Modern Language Journal  
BEARDSLEY Goucher College, Baltimore, Maryland BarjA, CESAR, Libros y autores contempordneos (Ganivet, Unamuno, Ortega y Gasset, Azorin, Baroja, Valle-Inclain, A. Machado, Pérez de Ayala).  ...  Visualizing Barja’s career, one notices a steady rise in quality, culminating in his study n Ortega y Gasset.  ... 
doi:10.2307/315733 fatcat:gip7nrhxa5g5flqn5s3dnfifty

Profesor GERARDO ORTEGA RODRÍGUEZ

Joaquín Hilario Pérez Labrador
2014 Revista de Ciencias Médicas de Pinar del Río  
Joaquín Hilario Pérez Labrador. Director-editor Rev. Ciencias Médicas.  ...  El pasado sábado 18 de enero fallece en la ciudad de Pinar del Río, el escritor, historiador y profesor Gerardo Ortega luego  ... 
doaj:6f1cc169d05949748210fdcf22918828 fatcat:z34wdlcbprgirmewhhd2grekje

The K-Means Algorithm Evolution [chapter]

Joaquín Pérez-Ortega, Nelva Nely Almanza-Ortega, Andrea Vega-Villalobos, Rodolfo Pazos-Rangel, Crispín Zavala-Díaz, Alicia Martínez-Rebollar
2019 Clustering [Working Title]  
Author details Joaquín Pérez-Ortega 1 *, Nelva Nely Almanza-Ortega 1 , Andrea Vega-Villalobos 1 , Rodolfo Pazos-Rangel 2 , Crispín Zavala-Díaz 3 Algorithm 1 . 1 Standard K-means algorithm 1: # Initialization  ... 
doi:10.5772/intechopen.85447 fatcat:oyidqzjs4zdinopc3pvjl6rn6a

Parallel processing of natural images by overlapping retinal neuronal ensembles [article]

Jesús Pérez-Ortega, Joaquín Araya, Cristobal Ibaceta, Rubén Herzog, María-José Escobar, Fernando Peña-Ortega, Luis Carrillo-Reid, Adrian G. Palacios
2021 bioRxiv   pre-print
AbstractEven though the retinal microcircuit organization has been described in detail at the single-cell level, little is known about how groups of retinal cells' coordinated activity encode and process parallel information representing the spatial and temporal structure of changing environmental conditions. To describe the population dynamics of retinal neuronal ensembles, we used microelectrode array recordings that describe hundreds of retinal ganglion cells' simultaneous activity in
more » ... activity in response to a short movie captured in the natural environment where our subject develops their visual behaviors. The vectorization of population activity allowed the identification of retinal neuronal ensembles that synchronize to specific segments of natural stimuli. These synchronous retinal neuronal ensembles were reliably activated by the same stimuli at different trials, indicating a robust population response of retinal microcircuits. The generation of asynchronous events required integrating a physiologically meaningful time window larger than 80 ms, demonstrating that retinal neuronal ensembles' time integration filters non-structured visual information. Interestingly, individual neurons could be part of several ensembles indicating that parallel circuits could encode environmental conditions changes. We conclude that parallel neuronal ensembles could represent the functional unit of retinal computations and propose that the further study of retinal neuronal ensembles could reveal emergent properties of retinal circuits that individual cells' activity cannot explain.
doi:10.1101/2021.02.22.432289 fatcat:7hks4eiklrgatiusdjcj3w3z3u

Dr. ANDRÉS JESÚS MARÍN ORTEGA IN MEMORIAM (1944 - 2009)

Joaquín Pérez Labrador
2009 Revista de Ciencias Médicas de Pinar del Río  
Joaquín Pérez Labrador, 24 de agosto de 2009. DIRECTOR  ... 
doaj:76dc227eeced4efdb304ba748c889fe2 fatcat:vft3rqbm3bgcxfe7n44mxzeowa

Balancing effort and benefit of K-means clustering algorithms in Big Data realms

Joaquín Pérez-Ortega, Nelva Nely Almanza-Ortega, David Romero, Yong Deng
2018 PLoS ONE  
OPEN ACCESS Citation: Pérez-Ortega J, Almanza-Ortega NN, Romero D (2018) Balancing effort and benefit of Kmeans clustering algorithms in Big Data realms. PLoS ONE 13(9): e0201874. https://doi.org/ 10.  ...  Investigation: Joaquín Pérez-Ortega, Nelva Nely Almanza-Ortega.  ...  Writing -review & editing: Joaquín Pérez-Ortega, Nelva Nely Almanza-Ortega, DavidRomero.  ... 
doi:10.1371/journal.pone.0201874 pmid:30183705 pmcid:PMC6124732 fatcat:e2n4aaxbsvc2vebttvoijrwwra

Characterization of Difficult Bin Packing Problem Instances oriented to Improve Metaheuristic Algorithms

Adriana Mexicano Santoyo, Joaquín Pérez Ortega, Gerardo Reyes Salgado, Nelva Nely Almanza Ortega
2015 Journal of Computacion y Sistemas  
Sus intereses de investigación incluyen Joaquín Pérez Ortega recibió el grado de Doctor por el Tecnológico de Monterrey.  ...  Enfoque de solución propuesto Computación y Sistemas, Vol. 19, No. 2, 2015, pp. 295-308 doi: 10.13053/CyS-19-2-1546 Adriana Mexicano Santoyo, Joaquín Pérez Ortega, Gerardo Reyes Salgado, Nelva Nely Almanza  ... 
doi:10.13053/cys-19-2-1546 fatcat:6irxrb5r2jhq7pkahumul5xshu

Gross Solids Content Prediction in Urban WWTPs Using SVM

Vanesa Mateo Pérez, José Manuel Mesa Fernández, Francisco Ortega Fernández, Joaquín Villanueva Balsera
2021 Water  
The preliminary treatment of wastewater at wastewater treatment plants (WWTPs) is of great importance for the performance and durability of these plants. One fraction that is removed at this initial stage is commonly called gross solids and can cause various operational, downstream performance, or maintenance problems. To avoid this, data from more than two operation years of the Villapérez Wastewater Treatment Plant, located in the northeast of the city of Oviedo (Asturias, Spain), were
more » ... Spain), were collected and used to develop a model that predicts the gross solids content that reaches the plant. The support vector machine (SVM) method was used for modelling. The achieved model precision (Radj2 = 0.7 and MSE = 0.43) allows early detection of trend changes in the arrival of gross solids and will improve plant operations by avoiding blockages and overflows. The results obtained indicate that it is possible to predict trend changes in gross solids content as a function of the selected input variables. This will prevent the plant from suffering possible operational problems or discharges of untreated wastewater as actions could be taken, such as starting up more pretreatment lines or emptying the containers.
doi:10.3390/w13040442 fatcat:x2m4bkkpinbt3knwe423vlrdsy

Percepción sobre ciencia y museo en estudiantes universitarios

Henry de Jesús Gallardo Pérez, Mawency Vergel Ortega, José Joaquín Martínez Lozano
2017 Logos Ciencia & Tecnología  
doi:10.22335/rlct.v8i2.387 fatcat:ksj72polrzeujflergnik65fea

Hoffmannseggia glauca (Ortega) Einfer (Fabaceae, Caesalpinioideae) nuevo metáfito en el Sur de la Península Ibérica (Málaga, España)

Baltasar Cabezudo, Federico Casimiro-Soriguer Solanas, Andrés V. Pérez-Latorre, Elías Dana, Joaquín Ramírez
2019 Acta Botanica Malacitana  
Hoffmannseggia glauca (Ortega) Einfer (Fabaceae, Cesalpinioideae) a new metaphyte in Southern Iberian Peninsula (Malaga, Spain)Palabras clave.  ...  Pérez-Latorre. MGC 69032 Linaria pedunculata, Eryngium maritimum o Elymus farctus.  ...  Pérez Latorre. MGC 702841 jrlmalaga@hotmail.com *Autor para correspondencia: bcabezudo@uma.es  ... 
doi:10.24310/abm.v34i0.6888 fatcat:bxztzpuosnbczdds5fopydeepy

The Hybrid Forecasting Method SVR-ESAR for Covid-19 [article]

Juan Frausto-Solis, Jose Enrique Olvera Vazquez, Juan Javier Gonzalez-Barbosa, Guadalupe Castilla-Valdez, Juan Paulo Sanchez-Hernandez, Joaquin Perez-Ortega
2020 medRxiv   pre-print
We know that SARS-Cov2 produces the new COVID-19 disease, which is one of the most dangerous pandemics of modern times. This pandemic has critical health and economic consequences, and even the health services of the large, powerful nations may be saturated. Thus, forecasting the number of infected persons in any country is essential for controlling the situation. In the literature, different forecasting methods have been published attempting to solve the problem. However, a simple and accurate
more » ... simple and accurate forecasting method is required for its implementation in any part of the world. This paper presents a precise and straightforward forecasting method named SVR-ESAR (Support Vector regression hybridized with the classical Exponential smoothing and ARIMA). We applied this method to the infected time series in four scenarios: the Whole World, China, the US, and Mexico. We compared our results with those of the literature showing the proposed method has the best accuracy.
doi:10.1101/2020.05.20.20103200 fatcat:j4y3b4nfwnfifkmknkxl5zfbmm

Time Series Complexities and Their Relationship to Forecasting Performance

Mirna Ponce-Flores, Juan Frausto-Solís, Guillermo Santamaría-Bonfil, Joaquín Pérez-Ortega, Juan J. González-Barbosa
2020 Entropy  
Entropy is a key concept in the characterization of uncertainty for any given signal, and its extensions such as Spectral Entropy and Permutation Entropy. They have been used to measure the complexity of time series. However, these measures are subject to the discretization employed to study the states of the system, and identifying the relationship between complexity measures and the expected performance of the four selected forecasting methods that participate in the M4 Competition. This
more » ... petition. This relationship allows the decision, in advance, of which algorithm is adequate. Therefore, in this paper, we found the relationships between entropy-based complexity framework and the forecasting error of four selected methods (Smyl, Theta, ARIMA, and ETS). Moreover, we present a framework extension based on the Emergence, Self-Organization, and Complexity paradigm. The experimentation with both synthetic and M4 Competition time series show that the feature space induced by complexities, visually constrains the forecasting method performance to specific regions; where the logarithm of its metric error is poorer, the Complexity based on the emergence and self-organization is maximal.
doi:10.3390/e22010089 pmid:33285864 pmcid:PMC7516527 fatcat:mph6jlleynfypm4qp6mc5babza

Methods to Evaluate Corrosion in Buried Steel Structures: A Review

Lorena-de Arriba-Rodriguez, Joaquin Villanueva-Balsera, Francisco Ortega-Fernandez, Fernando Rodriguez-Perez
2018 Metals  
Around the world, there are thousands of metal structures completely or partially buried in the soil. The main concern in their design is corrosion. Corrosion is a mechanism that degrades materials and causes structural failures in infrastructures, which can lead to severe effects on the environment and have direct impact on the population health. In addition, corrosion is extremely complex in the underground environment due to the variability of the local conditions. The problem is that there
more » ... blem is that there are many methods to its evaluation but none have been clearly established. In order to ensure the useful life of such structures, engineers usually consider an excess thickness that increases the economic cost of manufacturing and does not satisfy the principles of efficiency in the use of resources. In this paper, an extended revision of the existing methods to evaluate corrosion is carried out to optimize the design of buried steel structures according to their service life. Thus, they are classified into two categories depending on the information they provide: qualitative and quantitative methods. As a result, it is concluded that the most exhaustive methodologies for estimating soil corrosion are quantitative methods fed by non-electrochemical data based on experimental studies that measure the mass loss of structures.
doi:10.3390/met8050334 fatcat:fwqxiew5orgt7bdhx3zbwcqik4

Complexity of Instances for Combinatorial Optimization Problems [chapter]

Jorge A., Ocotlan Diaz-Parra, Joaquin Perez-Ortega, Rodolfo A. Pazos R., Gerardo Reyes, Juan Javier
2010 Computational Intelligence and Modern Heuristics  
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doi:10.5772/7807 fatcat:rq5ojafl4nbpnaxn5rccf7vtte

Selective visceral perfusion improves renal flow and hepatic function in neonatal aortic arch repair

Joaquín Fernández-Doblas, Christian Ortega-Loubon, Joaquín Pérez-Andreu, Marcos Linés, Manuel Fernández-Molina, Raúl F Abella
2018 Interactive Cardiovascular and Thoracic Surgery  
OBJECTIVES: The aortic arch repair in the neonatal period is a complex procedure with significant morbidity. We define a useful doubleperfusion technique and its effect on the function of abdominal organs in the postoperative course. METHODS: Nine patients with double perfusion (Group 1) were compared with 14 patients with antegrade cerebral perfusion (Group 2). The objective was to discern the incidence of postoperative acute kidney injury and impaired hepatic function, as well as tissue
more » ... ell as tissue perfusion and myocardial function parameters. Mechanical ventilation time, postoperative length of stay and 30-day mortality were measured. We excluded patients with extracorporeal membrane oxygenation, early mortality (<72 h) and preoperative renal or hepatic insufficiency. RESULTS: Nine (39%) patients developed postoperative acute kidney injury, with 22% (n = 2) in Group 1 and 50% (n = 7) in Group 2 (P = 0.183). A higher urine output was observed during the first 24 h for Group 1 (P = 0.032). Eleven patients developed impaired hepatic function in the immediate postoperative period: 2 (18.2%) in Group 1 and 9 (81.8%) in Group 2 (P = 0.04). The international normalized ratio (P = 0.006-0.031) and prothrombin time (P = 0.007-P = 0.016) were significantly lower in the double-perfusion group during the first 72 h. Significant difference was observed in lactate levels in the first 72 h (P = 0.001-0.009). There was no postoperative mortality in either group. CONCLUSIONS: Selective visceral perfusion is a safe procedure that provides a better urine output, hepatic function and tissue perfusion. This technique allows for the repair of complex aortic arch anomalies in neonates without deep hypothermic circulatory arrest.
doi:10.1093/icvts/ivy091 pmid:29590367 fatcat:g7arjoikkzcklappq7nukrsyw4
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