Multi-scale model for coupled piezoelectric-inelastic behavior

Moreno-Navarro, Pablo,Ibrahimbegovic, Adnan,Damjanovic, Dragan Techno-Press 2021 Coupled systems mechanics Vol.10 No.6

In this work, we present the development of a 3D lattice-type model at microscale based upon the Voronoi-cell representation of material microstructure. This model can capture the coupling between mechanic and electric fields with non-linear constitutive behavior for both. More precisely, for electric part we consider the ferroelectric constitutive behavior with the possibility of domain switching polarization, which can be handled in the same fashion as deformation theory of plasticity. For mechanics part, we introduce the constitutive model of plasticity with the Armstrong-Frederick kinematic hardening. This model is used to simulate a complete coupling of the chosen electric and mechanics behavior with a multiscale approach implemented within the same computational architecture.

Linear elastic mechanical system interacting with coupled thermo-electro-magnetic fields

Moreno-Navarro, Pablo,Ibrahimbegovic, Adnan,Perez-Aparicio, Jose L. Techno-Press 2018 Coupled systems mechanics Vol.7 No.1

A fully-coupled thermodynamic-based transient finite element formulation is proposed in this article for electric, magnetic, thermal and mechanic fields interactions limited to the linear case. The governing equations are obtained from conservation principles for both electric and magnetic flux, momentum and energy. A full-interaction among different fields is defined through Helmholtz free-energy potential, which provides that the constitutive equations for corresponding dual variables can be derived consistently. Although the behavior of the material is linear, the coupled interactions with the other fields are not considered limited to the linear case. The implementation is carried out in a research version of the research computer code FEAP by using 8-node isoparametric 3D solid elements. A range of numerical examples are run with the proposed element, from the relatively simple cases of piezoelectric, piezomagnetic, thermoelastic to more complicated combined coupled cases such as piezo-pyro-electric, or piezo-electro-magnetic. In this paper, some of those interactions are illustrated and discussed for a simple geometry.

Analytical and multicoupled methods for optimal steady-state thermoelectric solutions

Moreno-Navarro, Pablo,Perez-Aparicio, Jose L.,Gomez-Hernandez, J.J. Techno-Press 2022 Coupled systems mechanics Vol.11 No.2

Peltier cells have low efficiency, but they are becoming attractive alternatives for affordable and environmentally clean cooling. In this line, the current article develops closed-form and semianalytical solutions to improve the temperature distribution of Bi₂Te₃ thermoelements. From the distribution, the main objective of the current work-the optimal electric intensity to maximize cooling-is inferred. The general one-dimensional differential coupled equation is integrated for linear and quadratic geometry of thermoelements, under temperature constant properties. For a general shape, a piece-wise solution based on heat flux continuity among virtual layers gives accurate analytical solutions. For variable properties, another piece-wise solution is developed but solved iteratively. Taking advantage of the formulae, the optimal intensity is directly derived with a minimal computational cost; its value will be of utility for more advanced designs. Finally, a parametric study including straight, two linear, barrel, hourglass and vase geometries is presented, drawing conclusions on how the shape of the thermoelement affects the coupled phenomena. A specially developed coupled and non-linear finite element research code is run taking into account all the materials of the cell and using symmetries and repetitions. These accurate results are used to validate the analytical ones.

Electro-Oxidation in Combination with Biological Processes for Removal of Persistent Pollutants in Wastewater: A Review

Navarro-Franco, Javier A.,Garzon-Zuniga, Marco A.,Drogui, Patrick,Buelna, Gerardo,Gortares-Moroyoqui, Pablo,Barragan-Huerta, Blanca E.,Vigueras-Cortes, Juan M. The Korean Electrochemical Society 2022 Journal of electrochemical science and technology Vol.13 No.1

Persistent organic pollutants (POPs) and emerging pollutants (EP) are characterized by their difficulty to be removed through biological oxidation processes (BOPs); they persist in the environment and could have adverse effects on the aquatic ecosystem and human health. The electro-oxidation (EO) process has been successfully used as an alternative technique to oxidize many kinds of the aforementioned pollutants in wastewater. However, the EO process has been criticized for its high energy consumption cost and its potential generation of by-products. In order to decrease these drawbacks, its combination with biological oxidation processes has been reported as a solution to reduce costs and to reach high rates of recalcitrant pollutants removal from wastewaters. Thus, the location of EO in the treatment line is an important decision to make, since this decision affects the formation of by-products and biodegradability enhancement. This paper reviews the advantages and disadvantages of EO as a pre and post-treatment in combination with BOPs. A perspective of the EO scale-up is also presented, where hydrodynamics and the relationship of A/V (area of the electrode/working volume of the electrochemical cell) experiments are examined and discussed.

Assessment of buccal bone thickness of aesthetic maxillary region: a cone-beam computed tomography study

Fuentes, Ramon,Flores, Tania,Navarro, Pablo,Salamanca, Carlos,Beltran, Victor,Borie, Eduardo Korean Academy of Periodontology 2015 Journal of Periodontal & Implant Science Vol.45 No.5

Purpose: The aim of this study was to analyze the anatomical dimensions of the buccal bone walls of the aesthetic maxillary region for immediate implant placement, based upon cone-beam computed tomography (CBCT) scans in a sample of adult patients. Methods: Two calibrated examiners analyzed a sample of 50 CBCT scans, performing morphometric analyses of both incisors and canines on the left and right sides. Subsequently, in the sagittal view, a line was traced through the major axis of the selected tooth. Then, a second line (E) was traced from the buccal to the palatal wall at the level of the observed bone ridges. The heights of the buccal and palatal bone ridges were determined at the major axis of the tooth. The buccal bone thickness was measured across five lines. The first was at the level of line E. The second was at the most apical point of the tooth, and the other three lines were equidistant between the apical and the cervical lines, and parallel to them. Statistical analysis was performed with a significance level of $P{\leq}0.05$ for the bone thickness means and standard deviations per tooth and patient for the five lines at varying depths. Results: The means of the buccal wall thicknesses in the central incisors, lateral incisors and canines were $1.14{\pm}0.65mm$, $0.95{\pm}0.67mm$ and $1.15{\pm}0.68mm$, respectively. Additionally, only on the left side were significant differences in some measurements of buccal bone thickness observed according to age and gender. However, age and gender did not show significant differences in heights between the palatal and buccal plates. In a few cases, the buccal wall had a greater height than the palatal wall. Conclusions: Less than 10% of sites showed more than a 2-mm thickness of the buccal bone wall, with the exception of the central incisor region, wherein 14.4% of cases were ${\geq}2mm$.

Assessment of buccal bone thickness of aesthetic maxillary region: a conebeam computed tomography study

Ramón Fuentes,Tania Flores,Pablo Navarro,Carlos Salamanca,Víctor Beltrán,Eduardo Borie 대한치주과학회 2015 Journal of Periodontal & Implant Science Vol.45 No.5

Purpose: The aim of this study was to analyze the anatomical dimensions of the buccal bone walls of the aesthetic maxillary region for immediate implant placement, based upon cone-beam computed tomography (CBCT) scans in a sample of adult patients. Methods: Two calibrated examiners analyzed a sample of 50 CBCT scans, performing mor¬phometric analyses of both incisors and canines on the left and right sides. Subsequently, in the sagittal view, a line was traced through the major axis of the selected tooth. Then, a second line (E) was traced from the buccal to the palatal wall at the level of the observed bone ridges. The heights of the buccal and palatal bone ridges were determined at the ma¬jor axis of the tooth. The buccal bone thickness was measured across five lines. The first was at the level of line E. The second was at the most apical point of the tooth, and the other three lines were equidistant between the apical and the cervical lines, and parallel to them. Statistical analysis was performed with a significance level of P≤0.05 for the bone thick¬ness means and standard deviations per tooth and patient for the five lines at varying depths. Results: The means of the buccal wall thicknesses in the central incisors, lateral incisors and canines were 1.14±0.65 mm, 0.95±0.67 mm and 1.15±0.68 mm, respectively. Additionally, only on the left side were significant differences in some measurements of buccal bone thickness observed according to age and gender. However, age and gender did not show significant differences in heights between the palatal and buccal plates. In a few cases, the buccal wall had a greater height than the palatal wall. Conclusions: Less than 10% of sites showed more than a 2-mm thickness of the buccal bone wall, with the exception of the central incisor region, wherein 14.4% of cases were ≥2 mm.

Detection of Clavibacter michiganensis subsp. michiganensis Assisted by Micro-Raman Spectroscopy under Laboratory Conditions

Perez, Moises Roberto Vallejo,Contreras, Hugo Ricardo Navarro,Herrera, Jesus A. Sosa,Avila, Jose Pablo Lara,Tobias, Hugo Magdaleno Ramirez,Martinez, Fernando Diaz-Barriga,Ramirez, Rogelio Flores,Vazqu The Korean Society of Plant Pathology 2018 Plant Pathology Journal Vol.34 No.5

Clavibacter michiganensis subsp. michiganesis (Cmm) is a quarantine-worthy pest in $M{\acute{e}}xico$. The implementation and validation of new technologies is necessary to reduce the time for bacterial detection in laboratory conditions and Raman spectroscopy is an ambitious technology that has all of the features needed to characterize and identify bacteria. Under controlled conditions a contagion process was induced with Cmm, the disease epidemiology was monitored. Micro-Raman spectroscopy ($532nm\;{\lambda}$ laser) technique was evaluated its performance at assisting on Cmm detection through its characteristic Raman spectrum fingerprint. Our experiment was conducted with tomato plants in a completely randomized block experimental design (13 plants ${\times}$ 4 rows). The Cmm infection was confirmed by 16S rDNA and plants showed symptoms from 48 to 72 h after inoculation, the evolution of the incidence and severity on plant population varied over time and it kept an aggregated spatial pattern. The contagion process reached 79% just 24 days after the epidemic was induced. Micro-Raman spectroscopy proved its speed, efficiency and usefulness as a non-destructive method for the preliminary detection of Cmm. Carotenoid specific bands with wavelengths at 1146 and $1510cm^{-1}$ were the distinguishable markers. Chemometric analyses showed the best performance by the implementation of PCA-LDA supervised classification algorithms applied over Raman spectrum data with 100% of performance in metrics of classifiers (sensitivity, specificity, accuracy, negative and positive predictive value) that allowed us to differentiate Cmm from other endophytic bacteria (Bacillus and Pantoea). The unsupervised KMeans algorithm showed good performance (100, 96, 98, 91 y 100%, respectively).

E2E Network Slice Management Framework for 5G Multi-tenant Networks

Chirivella-Perez, Enrique Chirivella,Salva-Garcia, Pablo,Sanchez-Navarro, Ignacio,Alcaraz-Calero, Jose,Wang, Qi 한국통신학회 2023 Journal of communications and networks Vol.25 No.3

Network slicing is one of the cornerstone featuresof the fifth generation (5G) networks to enable the multiplexingof virtualised logical networks over the same physical networkinfrastructure for various vertical business services. Architecturesbased on network slicing enable network operators to offer end-to-end (E2E) vertical services whilst assuring fulfilling tailoredservice level agreement (SLA) requirements. Despite the numer-ous benefits that this concept offers, the need for efficient, scalableand holistic E2E management of network slicing significantlycomplicates network operators’ network management and im-poses significant challenges in the quality of service (QoS). Thispaper proposes a novel intent-based slice manager frameworkover a service base 5G architecture that allows flexible definitionsto customise network slices, automates all essential managementtasks for 5G network slice providers, manages the life cycles ofall sorts of network slices, and guarantees their QoS in a unifiednetwork slice management framework. The proposed frameworkis empirically validated in a realistic large-scale 5G multi-tenantinfrastructure. The high scalability of the framework is basedon the empirical results supporting more than 512 physicalmachines, 534288 virtual machines and more than two millionnetwork interfaces.

Detection of Clavibacter michiganensis subsp. michiganensis Assisted by Micro- Raman Spectroscopy under Laboratory Conditions

Moisé,s Roberto Vallejo Pé,rez,Hugo Ricardo Navarro Contreras,Jesú,s A. Sosa Herrera,José,Pablo Lara Á,vila,Hugo Magdaleno Ramí,rez Tobí,as,Fernando Dí,az-Barriga Mart& 한국식물병리학회 2018 Plant Pathology Journal Vol.34 No.5

Clavibacter michiganensis subsp. michiganesis (Cmm) is a quarantine-worthy pest in México. The implementation and validation of new technologies is necessary to reduce the time for bacterial detection in laboratory conditions and Raman spectroscopy is an ambitious technology that has all of the features needed to characterize and identify bacteria. Under controlled conditions a contagion process was induced with Cmm, the disease epidemiology was monitored. Micro-Raman spectroscopy (532 nm λ laser) technique was evaluated its performance at assisting on Cmm detection through its characteristic Raman spectrum fingerprint. Our experiment was conducted with tomato plants in a completely randomized block experimental design (13 plants × 4 rows). The Cmm infection was confirmed by 16S rDNA and plants showed symptoms from 48 to 72 h after inoculation, the evolution of the incidence and severity on plant population varied over time and it kept an aggregated spatial pattern. The contagion process reached 79% just 24 days after the epidemic was induced. Micro-Raman spectroscopy proved its speed, efficiency and usefulness as a non-destructive method for the preliminary detection of Cmm. Carotenoid specific bands with wavelengths at 1146 and 1510 cm-1 were the distinguishable markers. Chemometric analyses showed the best performance by the implementation of PCA-LDA supervised classification algorithms applied over Raman spectrum data with 100% of performance in metrics of classifiers (sensitivity, specificity, accuracy, negative and positive predictive value) that allowed us to differentiate Cmm from other endophytic bacteria (Bacillus and Pantoea). The unsupervised KMeans algorithm showed good performance (100, 96, 98, 91 y 100%, respectively).