609 research outputs found
Estimación de los parámetros de dependencia de la distribución generalizada de Pareto multivariada: relevancia en la medición de riesgo operativo
In this investigation is proved the expression of the angular density for the Generalized Pareto Multivariate Distribution, of the nested logistic type, for 3 variables and then scaled up to 5. Angular density is useful in implementing random variables simulation algorithms that follow this distribution, as well as for estimating its dependence parameters. Obtained expressions are used to estimate, by maximum likelihood, the dependence parameters for 5 variables with known parameters. The model fits well for AMA Operating Risk modeling. A method to define the hierarchical order that the variables must follow when the model is applied to empirical data, is presented.Distribución generalizada de Pareto multivariada, modelo logístico anidado, riesgo operativo, teoría de valores extremos
Propuesta de mejora en la gestión de inventarios e implementación de un sistema CPFR en una industria de planificación industrial
El favorable entorno macroeconómico del país, la volatilidad bastante marcada en el
precio de los commodities y las proyecciones de crecimiento del mercado e industria
del pan en el Perú en los últimos años, son indicadores que las principales empresas
industriales del rubro, deben tomar en cuenta para capitalizar logros y ser competitivas,
uno de los principales mecanismos para tal fin, es la gestión de sus sistemas logísticos.
De acuerdo con lo descrito, la presente tesis tiene por objetivo desarrollar una mejora
en la gestión de inventarios (a nivel de materias primas y producto terminado) y una
metodología de implementación de un sistema CPFR en la división de Panetones, una
de las categorías más importantes, en una empresa panificadora industrial con más de
diez años de funcionamiento en el Perú.
A través de las dos herramientas de mejora (que a su vez se complementan), se
estarán mejorando los flujos de información, tiempos de respuesta, visibilidad en la
cadena de suministro y la rentabilidad de la compañía.
Para las mejoras en la gestión de inventarios a nivel de materias primas se propone
implementar un sistema de revisión continua (ROP), el cual le permitirá a la empresa
reducir en 66,7 % los niveles de inventario generados, ahorrando S/. 1 252 564 y 45 430, previa inversión a 5 años en un sistema EDI.Tesi
Real-Time Context-Aware Microservice Architecture for Predictive Analytics and Smart Decision-Making
The impressive evolution of the Internet of Things and the great amount of data flowing through the systems provide us with an inspiring scenario for Big Data analytics and advantageous real-time context-aware predictions and smart decision-making. However, this requires a scalable system for constant streaming processing, also provided with the ability of decision-making and action taking based on the performed predictions. This paper aims at proposing a scalable architecture to provide real-time context-aware actions based on predictive streaming processing of data as an evolution of a previously provided event-driven service-oriented architecture which already permitted the context-aware detection and notification of relevant data. For this purpose, we have defined and implemented a microservice-based architecture which provides real-time context-aware actions based on predictive streaming processing of data. As a result, our architecture has been enhanced twofold: on the one hand, the architecture has been supplied with reliable predictions through the use of predictive analytics and complex event processing techniques, which permit the notification of relevant context-aware information ahead of time. On the other, it has been refactored towards a microservice architecture pattern, highly improving its maintenance and evolution. The architecture performance has been evaluated with an air quality case study
Time Series on Functional Service Life of Buildings using Fuzzy Delphi Method
The functional service life of heritage buildings, defined as the time period during which the building fulfils the requirements for which it was designed, is a complex system that has still not been fully resolved and continues to be the object of research regarding its social, economic and cultural importance. This paper presents an application for analysing time series that reflect the state of building performance over time. To this end, historical time records are used that provided data that could be interpreted by experts in the field. The latter can then evaluate the input variables (vulnerability and risk) using the expert system for predicting the service life of buildings, Fuzzy Building Service Life (FBSL), this methodology put together the fuzzy logic tools and Delphi method. This model provides output data on the state of functionality or performance of each buildings at each moment in time whenever information records are available. The Delphi Method is used to eliminate expert subjectivity, establishing an FDM-type assessment methodology that effectively quantifies the service life of buildings over time. The application is able to provide significant data when generating future preventive maintenance programmes in architectural-cultural heritage buildings. It can also be used to optimise the resources invested in the conservation of heritage buildings. In order to validate this system, the FDM methodology is applied to some specific building examples.Ministerio de Economía y Competitividad de España, Project ART-RISK - BIA2015-64878-RMinisterio de Economía y Competitividad de España MTM 2015-65397-
Targeting nicotine addiction: the possibility of a therapeutic vaccine
Cigarette smoking is the primary cause of lung cancer, cardiovascular diseases, reproductive disorders, and delayed wound healing all over the world. The goals of smoking cessation are both to reduce health risks and to improve quality of life. The development of novel and more effective medications for smoking cessation is crucial in the treatment of nicotine dependence. Currently, first-line smoking cessation therapies include nicotine replacement products and bupropion. The partial nicotinic receptor agonist, varenicline, has recently been approved by the US Food and Drug Administration (FDA) for smoking cessation. Clonidine and nortriptyline have demonstrated some efficacy, but side effects may limit their use to second-line treatment products. Other therapeutic drugs that are under development include rimonabant, mecamylamine, monoamine oxidase inhibitors, and dopamine D3 receptor antagonists. Nicotine vaccines are among newer products seeking approval from the FDA. Antidrug vaccines are irreversible, provide protection over years and need booster injections far beyond the critical phase of acute withdrawal symptoms. Interacting with the drug in the blood rather than with a receptor in the brain, the vaccines are free of side effects due to central interaction. For drugs like nicotine, which interacts with different types of receptors in many organs, this is a further advantage. Three anti-nicotine vaccines are today in an advanced stage of clinical evaluation. Results show that the efficiency of the vaccines is directly related to the antibody levels, a fact which will help to optimize the vaccine effect. The vaccines are expected to appear on the market between 2011 and 2012
Constitutive modeling of hot deformation of carbon steels in the intercritical zone
A previous constitutive modeling for single-phase steels is extended using the mixing law to predict the behavior of hot deformation in the dual phase ferritic-austenitic intercritical zone of Fe-C-Mn-Si alloys. Mixing law considers two phases instead one, so one phase formula was modified. The constant’s values used represents average values to the same conditions in austenitic and ferritic model. The amount of each phase is determined as function of temperature and chemical composition. The developed constitutive modeling is validated by comparing the theoretical stress-strain curves with experimental isothermal uniaxial compression tests of 1008 and 1035 carbon steels at different temperatures and strain rates. The compression tests were carried out in a dilatometer with the compression load at strain rate of 10-3, 10-2 and 10-1 s-1. A good agreement was obtained between the calculated and experimental results over different stages of deformation and hardening. Microstructural analysis was also carried out to relate the deformation results to the microstructure of the steels. Finally, a general constitutive equation has been proposed for hot deformation of steels in the intercritical zone.Peer ReviewedPostprint (published version
High temperature infiltration behavior of three volcanic ashes of YSZ APS-deposited thermal barrier coatings
Thermal Barrier Coatings (TBC) have enabled the increase of the operational temperature of aero engines. Raise in the turbine inlet temperatures (TIT) poses a threat to phase stability and safety for the state of the art material 7-8 wt% yttria stabilized zirconia (7YSZ). In addition to the inherent physicochemical restrictions of this material at high temperatures, the interaction of 7YSZ with siliceous airborne particles at temperatures above 1200 °C has been a major concern since the last decades. Sediments of Calcium-Magnesium-Aluminum-Silicates (CMAS) have been found in failed engines and have been correlated to the failure mechanisms of high temperature components. In 2010 the eruption of the Eyjafjallajökull volcano in Iceland heavily disrupted air traffic in Europe. This volcanic event lead to regulations regarding volcanic ash (VA) concentrations in the atmosphere at which aircrafts are allowed to safely fly. Also, it brought to sight the risks associated to VA in the safety of aircrafts with routes close to active volcanos. Nevertheless, reports of the assessment of the high temperature risk using real volcanic ashes is still limited in comparison to analyses carried out with CMAS. Additionally, most reported studies have been focused on the study of electron beam physical vapor deposition (EB-PVD) rather than atmospheric plasma spray (APS) produced TBCs. This contribution addresses the study of the infiltration mechanisms of VA from three sources: Colima and Popocatepetl Mexican volcanoes as well as Eyjafjallajökull Icelandic volcano.
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Diseño de un arreglo de antenas dipolo doblado para la banda de onda milimétrica
El artículo presenta el diseño
numérico de arreglos lineales de 2, 3 y 4
antenas de dipolo doblado en la banda de ondas
milimétricas a una frecuencia de 26 GHz
mediante el software de simulación EMPro.
Como material conductor se utilizó el cobre y
como dieléctrico el sustrato FR4. Se analizaron
los parámetros de desempeño como coeficiente
de reflexión, relación de onda estacionaria,
patrones de radiación, demostrando que el
arreglo (4x1) obtuvo los mejores resultados.
Con un S11 de -35.67 [dB], ancho de banda
(bandwidth- BW) de 70 [MHz], VSWR o ROE
de 1.03, con una ganancia de 5.82 [dBi],
directividad de 7.99 [dBi] y eficiencia radiada
de 59.97 [%], en comparación a los demás
diseños.The paper presents the numerical
design of linear arrays of the 2, 3 and 4
antennas of folded dipole in the millimeter
wave at a frequency of 26 GHz using EMPro
simulation software. Copper was used as
conductive material and FR4 substrate as
dielectric. Performance parameters such as
reflection coefficient, standing wave ratio,
radiation patterns were analysed, showing that
the array (4x1) obtained the best results. S11 of
-35.67 [dB], BW of 70 [MHz], VSWR or SWR
of 1.03, with a gain of 5.82 [dBi], directivity of
7.99 [dBi] and radiated efficiency of 59.97 [%],
compared to the other designs
Aplicación del sistema de nanoburbuja de aire y filtro de quitosano - óxido de grafeno para mejorar la calidad del agua en la cuenca baja del río Chillón – Ventanilla 2021
Esta investigación permitió determinar en qué medida la aplicación del sistema
nanoburbujas de aire y filtro de quitosano - óxido de grafeno mejora la calidad del
agua de la cuenca baja del río Chillón - Ventanilla – 2021. Se realizó un muestreo
de aguas en la cuenca media, siguiendo protocolo para monitoreo de calidad de los
recursos hídricos superficiales; se introdujeron en un sistema de nanoburbujas a 70
PSI, a 30, 60 y 90 minutos; finalmente cada muestra se pasó por un filtro base
quitosano - óxido de grafeno. Se evaluaron los parámetros fisicoquímicos
(Conductividad, pH, Temperatura, DBO5, OD, N amoniacal y Turbidez) y
microbiológicos (coliformes termotolerantes y totales), antes y después de los
tratamientos.
En los resultados relevantes se encontró que a solo 30 minutos se presentó
remoción en 87% de aceites y grasas (mg/L) y 98.21% de turbiedad (NTU); además
a 90 minutos una reducción de 61.86 % en conductividad eléctrica (μS/cm), así
como los parámetros microbiológicos en un 99,99%. Concluyéndose que con el
sistema nanoburbujas y filtro de quitosano - óxido de grafeno se redujeron los
parámetros fisicoquímicos y microbiológicos por debajo de los estándares de
calidad ambiental, mejorando las aguas de la cuenca baja del río Chillón
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