1,958 research outputs found

    Chassis design for an autonomous electric vehicle for the city of Cartagena de Indias (Elevated Autonomous Transport System-Caribbean railway) using finite elements and the Shell technique

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    SciVal Topics Metrics Abstract This document contains the chassis design for an autonomous electric vehicle. First, a fatigue failure analysis should be done to the underside of the chassis under fluctuating loads. Subsequently, the methodology of the shell technique or plate technique is applied to make the structural analysis by finite elements of the complete structure. The results show a satisfactory design that meets all the criteria used. © 2020 IEEE

    Preconditioned iterative methods for convection diffusion and related boundary value problems

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    AbstractWe develop and analyze preconditioners for the iterative solution of the system of equations arising from the discretization of multi-dimensional singularity perturbed boundary value problems. This includes a class of convection diffusion models. The choice of preconditioner is crucial for the efficient solution of the system of equations. In particular, it is necessary to choose a preconditioner that substantially reduces the condition number κ both for small grid size h and for large values of the parameter K multiplying the convection terms. A class of preconditioners is analyzed that is inexpensive to implement and for which κ = 0(1) as h→0 and κ = (1 + K12) as K → ∞ for some convection diffusion problems with positive definite symmetric part. This result is then used to develop an algorithm with work estimate 0(1 + K12as K → ∞ for a more general class of convection diffusion problems including those with indefinite symmetric part. Numerical experiments using a symmetric multigrid preconditioner demonstrate the effectiveness of the numerical method even for large problems

    Surface shape resonances in lamellar metallic gratings

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    The specular reflectivity of lamellar gratings of gold with grooves 0.5 microns wide separated by a distance of 3.5 microns was measured on the 2000 cm1^{-1} - 7000 cm1^{-1} spectral range for p-polarized light. For the first time, experimental evidence of the excitation of electromagnetic surface shape resonances for optical frequencies is given. In these resonances the electric field is highly localized inside the grooves and is almost zero in all other regions. For grooves of depth equal to 0.6 microns, we have analyzed one of these modes whose wavelength (3.3 microns) is much greater than the lateral dimension of the grooves.Comment: 4 pages (LaTex), 5 postscript figures, to be published in Physical Review Letter

    Quantum entanglement patterns in the structure of atomic nuclei within the nuclear shell model

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    Quantum entanglement offers a unique perspective into the underlying structure of strongly-correlated systems such as atomic nuclei. In this paper, we use quantum information tools to analyze the structure of light and medium mass berillyum, oxygen, neon and calcium isotopes within the nuclear shell model. We use different entanglement metrics, including single-orbital entanglement, mutual information, and von Neumann entropies for different equipartitions of the shell-model valence space and identify mode/entanglement patterns related to the energy, angular momentum and isospin of the nuclear single-particle orbitals. We observe that the single-orbital entanglement is directly related to the number of valence nucleons and the energy structure of the shell, while the mutual information highlights signatures of proton-proton and neutron-neutron pairing. Proton and neutron orbitals are weakly entangled by all measures, and in fact have the lowest von Neumann entropies among all possible equipartitions of the valence space. In contrast, orbitals with opposite angular momentum projection have relatively large entropies. This analysis provides a guide for designing more efficient quantum algorithms for the noisy intermediate-scale quantum era.Comment: Submitted to EPJA Topical Issue "Quantum computing in low-energy nuclear theory

    Aspectos epidemiológicos y clinicos del Colangio carcinoma en el Hospital Nacional Edgardo Rebagliati Martins - EsSalud, 2006 -2012: Epidemiological and clinical aspects of Cholangio carcinoma in the National Hospital Edgardo Rebagliati Martins EsSalud, 2006 - 2012

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    Objetivo. Determinar el comportamiento epidemiológico y clínico del Colangiocarcinoma (CCA) en un hospital referencial como el Hospital Nacional Edgardo Rebagliati Martins EsSalud en el periodo del 2006 al 2012 en Lima-Perú. Materiales y m´étodos. Se realizó un estudio descriptivo, retrospectivo longitudinal en base a la recopilación de datos registrados en las historias clínicas de los pacientes del Hospital Nacional Edgardo Rebagliati Martins, cuyo diagnóstico definitivo se haya establecido bajo la codificación internacional CIE 10 con el código 24.0 o también conocido como Neoplasia Maligana de Vía Biliar o Colangiocarcinoma, comprendidos entre el año 2006 al 2012. El universo de estudio fue de 90 pacientes (2006-2012) de los cuales se calculó como tamañno de muestra válido a 60 de ellos que cumplian con los criterios de inclusión y exclusión. Resultados. En relación a los resultados, muchos de los aspectos epidemiológicos difieren de lo estudiado en otras poblaciones, sobretodo las pertenientes al continente Asiatico, donde se pueden encontrar asociadas factores de riesgo como Colangitis Esclerosante Primaria o la presencia de parásitos propios de la localidad. Así también la incidencia, prevalencia y distribución por grupo etáreo y por género, mortalidad y tiempo de sobrevida varían en relación a características diagnósticas y estudios realizados previamente en países como Japón, China e Israel. Conclusiones. Se concluye que el Colangiocarcinoma es una neoplasia de via bibliar con una incidencia de 1 caso nuevo / 100,000 habitantes en nuestro país. Se describe una predominancia de aparición en personas de sexo femenino y ello se incrementa a partir de la sexta década de la vida. En nuestra población se asocia a antecedentes de litiasis vesicular, hepatitis viral y colecistectomía previa en su mayoria. Clinicamente el CCI se asocia más a disminución de peso, mientras que en el CCE predomina la ictericia. La mayoria de pacientes son diagnósticados en estadios avanzados III y IV, presentándose una mortalidad elevada y un tiempo de sobrevida de 1 mes y un m´´aximo de 73 meses

    A cooperative game approach to a production planning problem

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    This paper deals with a production planning problem formulated as a Mixed Integer Linear Programming (MILP) model that has a competition component, given that the manufacturers are willing to produce as much products as they can in order to fulfil the market’s needs. This corresponds to a typical game theoretic problem applied to the productive sector, where a global optimization problem involves production planning in order to maximize the utilities for the different firms that manufacture the same type of products and compete in the market. This problem has been approached as a cooperative game, which involves a possible cooperation scheme among the manufacturers. The general problem was approached by Owen (1995) as the “production game” and the core was considered. This paper identifies the cooperative game theoretic model for the production planning MILP optimization problem and Shapley Value was chosen as the solution approach. The results obtained indicate the importance of cooperating among competitors. Moreover, this leads to economic strategies for small manufacturing companies that wish to survive in a competitive environment

    Evolutionary diversity peaks at mid-elevations along an Amazon-to-Andes elevation gradient

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    Elevation gradients present enigmatic diversity patterns, with trends often dependent on the dimension of diversity considered. However, focus is often on patterns of taxonomic diversity and interactions between diversity gradients and evolutionary factors, such as lineage age, are poorly understood. We combine forest census data with a genus level phylogeny representing tree ferns, gymnosperms, angiosperms, and an evolutionary depth of 382 million years, to investigate taxonomic and evolutionary diversity patterns across a long tropical montane forest elevation gradient on the Amazonian flank of the Peruvian Andes. We find that evolutionary diversity peaks at mid-elevations and contrasts with taxonomic richness, which is invariant from low to mid-elevation, but then decreases with elevation. We suggest that this trend interacts with variation in the evolutionary ages of lineages across elevation, with contrasting distribution trends between younger and older lineages. For example, while 53% of young lineages (originated by 10 million years ago) occur only below ∼1,750 m asl, just 13% of old lineages (originated by 110 million years ago) are restricted to below ∼1,750 m asl. Overall our results support an Environmental Crossroads hypothesis, whereby a mid-gradient mingling of distinct floras creates an evolutionary diversity in mid-elevation Andean forests that rivals that of the Amazonian lowlands

    Neuro-fuzzy control for artificial pancreas: in silico development and validation

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    [ES] La Diabetes Mellitus Tipo 1 (DMT1) es una de las enfermedades actuales más dañinas que afectan a personas de cualquier edad incluyendo niños desde el nacimiento. Las inyecciones de insulina exógena siguen siendo el tratamiento más común para estos pacientes, sin embargo, no es el óptimo. La comunidad científica se ha esforzado en optimizar el suministro de insulina usando dispositivos electrónicos y de esta manera mejorar la esperanza de vida de los diabéticos. Existen numerosas limitaciones para que esta evolución biomédica sea realidad tales como la validación de algoritmos controladores, experimentación con dispositivos electrónicos, aplicabilidad en pacientes de diferentes edades, entre otras. Este trabajo presenta el prototipado de un controlador inteligente neuro-fuzzy en la tarjeta LAUNCHXL-F28069M de Texas Instruments para formar un esquema de hardware en el lazo (HIL). Esto es, el controlador embebido manda los datos de la tasa de suministro de insulina al computador donde se capturan por el software Uva/Padova y se integran a la simulación metabólica de pacientes diabéticos virtuales tratados con bomba de insulina. Una tarea principal del algoritmo inteligente embebido es determinar la tasa óptima de infusión insulínica para cada uno de los 30 pacientes virtuales disponibles, los cuales llevan un protocolo de comida. La novedad de este trabajo se centra en superar las limitaciones actuales a través de un primer enfoque de algoritmo de control inteligente aplicable al páncreas artificial (PA) y analizar la factibilidad de esta propuesta en la trascendencia con la edad ya que los resultados corresponden a pruebas in-silico en poblaciones de 10 adultos, 10 adolescentes y 10 niños.[EN] Type 1 Diabetes Mellitus (DMT1) is currently one of the most harmful diseases that aect people of any age, including children from birth. Exogenous insulin injections remain the most common treatment for these patients, however, it is not the optimal one. The scientific community has endeavored to optimize insulin administration using electronic devices and thus improve the diabetics life expectancy. There are numerous limitations for this biomedical evolution to become a reality such as the control algorithms validation, experimentation with electronic devices, and applicability in patients age transcendence, among others. This work presents the prototyping of a neuro-fuzzy intelligent controller on the Texas Instruments LAUNCHXL-F28069M development board to form a hardware in the loop (HIL) scheme. That is, the embedded controller sends the insulin delivery rate data to the computer where it is captured by the Uva/Padova software and integrated into the metabolic simulation of virtual diabetic patients treated with an insulin pump. The main task of the embedded intelligent algorithm is to determine the optimal insulin infusion rate for each of the 30 virtual patients who follow a meal protocol. The novelty of this work focuses on overcoming current limitations through a first intelligent control algorithm approach applicable to artificial pancreas (AP) and analyzing the feasibility of this proposal in age transcendence since the results correspond to in-silico tests in populations of 10 adults, 10 adolescents and 10 children.Rios, Y.; García-Rodríguez, J.; Sánchez, E.; Alanis, A.; Ruiz-Velázquez, E.; Pardo, A. (2020). Control neuro-fuzzy para páncreas artificial: desarrollo y validación in-silico. Revista Iberoamericana de Automática e Informática industrial. 17(4):390-400. https://doi.org/10.4995/riai.2020.13035OJS390400174Alanis, A. Y., Sanchez, E. N., Loukianov, A. G., 2007. Discrete-Time Adaptive Backstepping Nonlinear Control via High-Order Neural Networks. 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Birkhäuser Boston, Boston. https://doi.org/10.1007/978-0-8176-4759-9Geman, O., Chiuchisan, I., Toderean, R., 2017. Application of adaptive neuro-fuzzy inference system for diabetes classification and prediction. In: 2017 E-Health and Bioengineering Conference (EHB). Sinaia, pp. 639-642. https://doi.org/10.1109/EHB.2017.7995505Institute of Medicine, 2005. Summary Tables, Dietary Reference Intakes. In: Press, T. N. A. (Ed.), Dietary Reference Intakes for Energy, the nation Edition. Elsevier, Washington D.C, U.S., Ch. Summary Ta, pp. 1319-1331. https://doi.org/10.17226/10490Karahoca, A., Karahoca, D., Kara, A., sep 2009. Diagnosis of diabetes by using adaptive neuro fuzzy inference systems. In: 2009 Fifth International Conference on Soft Computing, Computing with Words and Perceptions in System Analysis, Decision and Control. Famagusta, pp. 1-4. https://doi.org/10.1109/ICSCCW.2009.5379497Kim, S., 2007. Burden of hospitalizations primarily due to uncontrolled diabetes. Diabetes Care 30 (5), 1281-1282. http://care.diabetesjournals.org/content/30/5/1281 , https://doi.org/10.2337/dc06-2070Kovatchev, B., Raimondo, D., Breton, M., Patek, S., Cobelli, C., jan 2008. In Silico Testing and in Vivo Experiments with Closed-Loop Control of Blood Glucose in Diabetes. IFAC Proceedings Volumes 41 (2), 4234-4239. https://doi.org/10.3182/20080706-5-KR-1001.00712Kovatchev, B. P., Breton, M., Dalla Man, C., Cobelli, C., 2009. In silico preclinical trials: A proof of concept in closed-loop control of type 1 diabetes. Journal of Diabetes Science and Technology 3 (1), 44-55. https://doi.org/10.1177/193229680900300106Kropff, J., et al., December 2015. 2 month evening and night closed-loop glucose control in patients with type 1 diabetes under free-living conditions: a randomised crossover trial. The Lancet Diabetes & Endocrinology 3 (2), 939-947. https://doi.org/10.1016/S2213-8587(15)00335-6Kux, L., 2012. Guidance for Industry and Food and Drug Administration Staff; The Content of Investigational Device Exemption and Premarket Approval Applications for Artificial Pancreas Device Systems; Availability. Federal Register 77 (226), 1-63.Lekkas, S., Mikhailov, L., 2010. Evolving fuzzy medical diagnosis of Pima Indians diabetes and of dermatological diseases. Artificial Intelligence in Medicine 50 (2), 117-126. https://doi.org/10.1016/j.artmed.2010.05.007Leon, B. S., Alanis, A. Y., Sanchez, E. N., Ornelas-Tellez, F., Ruiz-Velazquez, E., 2013. Neural inverse optimal control applied to type 1 diabetes mellitus patients. Analog Integrated Circuits and Signal Processing 76 (3), 343-352. https://doi.org/10.1007/s10470-013-0109-8Li, W., Todorov, E., Liu, D., 2011. Inverse optimality design for biological movement systems. In: IFAC Proceedings Volumes (IFAC-PapersOnline). Vol. 44. Elsevier, Milano, pp. 9662-9667. https://doi.org/10.3182/20110828-6-IT-1002.00877Nath, A., Dey, R., Balas, V. E., 2018. 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An advanced bolus calculator for type 1 diabetes: System architecture and usability results. IEEE Journal of Biomedical and Health Informatics 20 (1), 11-17. https://doi.org/10.1109/JBHI.2015.2464088Rios, Y. Y., Garcia-Rodriguez, J., Sanchez, E. N., Alanis, A. Y., Ruiz-Velazquez, E., 2018a. Rapid Prototyping of Neuro-Fuzzy Inverse Optimal Control as Applied to T1DM Patients. In: 2018 IEEE Latin American Conference on Computational Intelligence (LA-CCI). IEEE, Guadalajara, pp. 1-5. https://doi.org/10.1109/LA-CCI.2018.8625241Rios, Y. Y., García-Rodríguez, J. A., Sanchez, E. N., Alanis, A. Y., Ruiz-Velázquez, E., Durán, C., 2018b. Treatment for T1DM patients using neuro-fuzzy inverse optimal control algorithm: a rapid prototyping implementation. In: Revista Colombiana de Tecnologías de Avanzada. Colombia, pp. 26-33.Rios, Y. Y., García-Rodríguez, J. A., Sánchez, O. D., Sanchez, E. N., Alanis, A. Y., Ruiz-Velázquez, E., Arana-Daniel, N., 2018c. 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    Control neuro-fuzzy para páncreas artificial: Desarrollo y validación in-silico

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    Type 1 Diabetes Mellitus (DMT1) is currently one of the most harmful diseases that affect people of any age, including children from birth. Exogenous insulin injections remain the most common treatment for these patients, however, it is not the optimal one. The scientific community has endeavored to optimize i nsulin administration using electronic devices and thus improve the diabetics life expectancy. There are numerous limitations for this biomedical evolution to become a reality such as the control algorithms validation, experimentation with electronic devices, and applicability in patients age transcendence, among others. This work presents the prototyping of a neuro-fuzzy intelligent controller on the Texas Instruments LAUNCHXL-F28069M development board to form a hardware in the loop (HIL) scheme. That is, the embedded controller sends the insulin delivery rate data to the computer where it is captured by the Uva/Padova software and integrated into the metabolic simulation of virtual diabetic patients treated with an insulin pump. The main task of the embedded intelligent algorithm is to determine the optimal insulin infusion rate for each of the 30 virtual patients who follow a meal protocol. The novelty of this work focuses on overcoming current limitations through a first intelligent control algorithm a pproach applicable to artificial pancreas (A P) and an alyzing the feasibility of this proposal in age transcendence since the results correspond to in-silico tests in populations of 10 adults, 10 adolescents and 10 children. © 2020 Universitat Politecnica de Valencia. All rights reserved
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