Sagnac loop in ring resonators for tunable optical filters

General filter architecture using co- and counterpropagation signals are studied. A specific configuration based on a Sagnac loop within a ring resonator is analyzed. Novel tuning, apart from conventional tuning, is achieved by changing the coupling ratio of a coupler through the adjustment of the equivalent loop length. Full equations describing the filter behavior in passive and active configurations, and simple closed-form formulas to compute the tuning, tolerance, and full-width at half-maximum are reported. The performance of these devices is discussed for their application as selective or channel-dropping ultra-narrow-band filters. The effect of losses and their dispersion properties are also discussed. These devices can be conveniently implemented, using silicon- or InP-integrated optic technology, for they have high free spectral ranges.Publicad

Measurements On Passive Tunable Optical Filters For DWDM

WFOPC 2002 IEEE/LEOS Workshop on Fibre and Optical Passive Components, University of Glasgow, Scotland, on 5th-6th June 2002.Measurements on a passive optical fibre tunable filter are presented. The device is based on a loop mirror in a ring resonator. The loop mirror allows tuning by changing the coupling coefficient of a coupler. The novel filter structure allows planar optical integration for having higher free spectral ranges. Novel and simple design equations for the filter parameters and the tuning process are reported. There is a good agreement between measurements and theory.Universidad Carlos III de MadridPublicad

Tunable Optical Filters Using Compound Ring Resonators for DWDM

The device is based on a loop mirror in a ring resonator. The loop mirror allows tuning by changing the coupling coefficient of a directional coupler. The loop mirror is implemented using a Sagnac configuration to have the same optical path between the signals to be interfered (copropagating and counterpropagating ones). The filter structure allows optical integration for having higher free-spectral ranges. Simple design equations for the filter parameters and the tuning are reported. Measurements on a passive optical fiber tunable filter are presented. There is a good agreement between measurements and theory.Publicad

Hábitos de estudio en el rendimiento académico de estudiantes de topografía del 3er. ciclo de Arquitectura de la UPC, Lima 2019

La tesis de maestría titulada hábitos de estudio en el rendimiento académico de estudiantes de Topografía del 3er ciclo de Arquitectura de la UPC, Lima 2019, se realiza con el motivo de que muchos estudiantes tienen problemas en las evaluaciones, esto no es reflejo de un bajo esfuerzo, sino más bien de la falta en el método de estudio. Entonces lo que se quiere saber es si hay relación entre los hábitos de estudio y el rendimiento académico. El método de investigación es el hipotético deductivo, con un enfoque cuantitativo y diseño de investigación no experimental, transaccional – correlacionar - causal, con una muestra universal de 23 estudiantes, se utilizó el inventario de hábitos de estudio de Luis Vicuña Peri, de esta manera el análisis de procesamiento de datos es por medio de la regresión ordinal. Finalmente los resultados descriptivos indican de que existe correlación significativa entre los hábitos de estudio y el rendimiento académico, donde prevalece un logro esperado en el rendimiento académico con 56.5% y por ultimo un rendimiento académico en inicio con un 8.7%. Los resultados inferenciales indican que el chi-cuadrado calculado de tabla para un α: ,05 es 5.99, así comparándolo con lo obtenido en spss tenemos que 11.048 > 5.99 y el resultado de la curva de COR con el 84.2 % del área de la curva, todos estos resultados significan que se debe aceptar la dependencia de la variable. Se concluye indicando la necesidad de que se evalué con este inventario a los alumnos para indicarles sus debilidades en el estudio

Problemática derivada de la aplicación por la Administración tributaria del procedimiento de comprobación de valores.

El procedimiento de comprobación de valores es uno de los procedimientos tributarios que mayor conflictividad está generando en la actualidad, especialmente por la frecuencia en que es utilizado en el Impuesto sobre Transmisiones Patrimoniales y Actos Jurídicos Documentados y en el Impuesto sobre Sucesiones y Donaciones por la Administración tributaria competente para ello. La conflictividad al respecto tiene, a nuestro juicio, causa en dos razones. La primera es el contexto de crisis económica que dificulta la liquidez tanto de Administración como de contribuyente y que obliga a la primera a una especial atención en la medición de la capacidad económica que se refleja en las operaciones gravadas por dichos impuestos. La segunda razón de la conflictividad es el recurso casi exclusivo de la Administración tributaria a métodos objetivos no siempre permeables a la variabilidad de valores de los bienes en el contexto actual. Desde esas premisas, el Trabajo Fin de Grado analiza el procedimiento de comprobación de valores estudiando el grado de discrecionalidad de la Administración en su aplicación y las garantías y medios de defensa del ciudadano en tal procedimiento. Se parte de un ineludible estudio genérico del procedimiento de valores, con especial atención a su evolución histórica que ha cambiado su concepción de un procedimiento parte de otro procedimiento a la de procedimiento autónomo. A partir de ahí, se estudia el concepto de valor y se relaciona con la base imponible para entender el objeto de la comprobación, especialmente complicado en la determinación del valor real. Con esa base teórica, se analiza los dos puntos más importantes del procedimiento de comprobación de valores: los medios de valoración y la tasación pericial contradictoria (en adelante, TPC), como respuesta. De los medios de valoración se discute, en primer lugar, la discrecionalidad de la Administración a la hora de elegir el método y se analizan, en segundo lugar, los métodos más importantes por su aplicación práctica. En segundo lugar, respecto a la tasación pericial contradictoria, se analiza como procedimiento autónomo, comparando las Comprobación de valores y determinación del valor real 4 diferencias que existen entre las distintas normas que se ocupan de ella. Como conjunto, no sólo se expone el régimen jurídico de estas cuestiones, sino que se abordan los principales problemas y se determinan soluciones que ayuden a disminuir la polémica social y la litigiosidad jurídica que este procedimiento viene suscitando

Evaluation of Presence in Virtual Environments: Haptic Vest and User's Haptic Skills

This paper presents the integration of a haptic vest with a multimodal virtual environment, consisting of video, audio, and haptic feedback, with the main objective of determining how users, who interact with the virtual environment, benefit from tactile and thermal stimuli provided by the haptic vest. Some experiments are performed using a game application of a train station after an explosion. The participants of this experiment have to move inside the environment, while receiving several stimuli to check if any improvement in presence or realism in that environment is reflected on the vest. This is done by comparing the experimental results with those similar scenarios, obtained without haptic feedback. These experiments are carried out by three groups of participants who are classified on the basis of their experience in haptics and virtual reality devices. Some differences among the groups have been found, which can be related to the levels of realism and synchronization of all the elements in the multimodal environment that fulfill the expectations and maximum satisfaction level. According to the participants in the experiment, two different levels of requirements are to be defined by the system to comply with the expectations of professional and conventional users

Optical router for optical fiber sensor networks based on a liquid crystal cell

Optical fiber sensor networks are evolving rapidly. They are used because of the inert nature of optical fibers allowing no electromagnetic interference and safe applications in inflammable atmospheres; other relevant characteristics are their low weights and wide bandwidths as a transmission medium. In any case, it is very interesting to have specific components such as optical routers for selecting a certain path in a network with no optical to electrical and electrical to optical conversions. In this paper, we propose an all-optical router based on liquid crystals, polarizers, and a spatial split polarization beam splitter. The implemented device is designed to operate with visible light and it has been tested with plastic optical fibers. It has a crosstalk of 14 dB between selected ON channels and nonoperative OFF channels and 11-dB insertion losses. An average switch time of 100 ms is measured. The device checks the optical power level in each channel and, in case of failure, automatically switches to an operative channel while an alarm is activated.Publicad

Animal models of maladaptive traits: disorders in sensorimotor gating and attentional quantifiable responses as possible endophenotypes

Traditional diagnostic scales are based on a number of symptoms to evaluate and classify mental diseases. In many cases, this process becomes subjective, since the patient must calibrate the magnitude of his/her symptoms and therefore the severity of his/her disorder. A completely different approach is based on the study of the more vulnerable traits of cognitive disorders. In this regard, animal models of mental illness could be a useful tool to characterize indicators of possible cognitive dysfunctions in humans. Specifically, several cognitive disorders such as schizophrenia involve a dysfunction in the mesocorticolimbic dopaminergic system during development. These variations in dopamine levels or dopamine receptor sensibility correlate with many behavioral disturbances. These behaviors may be included in a specific phenotype and may be analyzed under controlled conditions in the laboratory. The present study provides an introductory overview of different quantitative traits that could be used as a possible risk indicator for different mental disorders, helping to define a specific endophenotype. Specifically, we examine different experimental procedures to measure impaired response in attention linked to sensorimotor gating as a possible personality trait involved in maladaptive behaviors.Ministerio de Economía y Competitividad PSI2012- 3244

Amygdala and emotional learning in vertebrates: A comparative perspective

Gobierno de España SI2009-12761Gobierno de España RyC2006/128

Evaluation in High Education Based On a Multi-Criteria Methodology: Application to a Course on Power Systems

[EN] After the adoption of the Bologna Plan by European Universities, the classical method used to evaluate students by traditional exams has changed, so that a wide typology of evaluation mechanisms haveappeared. By means of those mechanisms, students may be evaluated according to the specific and transversal competences they have acquired during their degree. In this contribution, the authors present a methodology, based on a multi-criteria procedure, which could be used to evaluate University students from different perspectives so as to obtain an objective assessment about the level of achievement of such competences. The proposed methodology has been applied during the last four years to the course onPower Systems that is taught in the Master Degree in Industrial Engineering at the Polytechnic University of Valencia, Spain, whose results are also presented here.Alcázar-Ortega, M.; Montuori, L.; Vargas-Salgado, C.; Rodríguez-García, J. (2022). Evaluation in High Education Based On a Multi-Criteria Methodology: Application to a Course on Power Systems. Specialusis Ugdymas. 43(2):3486-3496. http://hdl.handle.net/10251/1912103486349643