Electric Field Sensing Schemes Using Low-Coherence Light and LiNbO3 Electrooptical Retarders

Non

Software Defined Radio for processing GNSS signals

GPS satellites are fitted with atomic clocks, in which it relapses the main objective of this project, to recover some of their accuracy and stability on a ground based receiver. This project describes the fundamentals of GPS signals, the assembly of the installation implemented to process them in software and the corresponding experiments. In order to achieve the software processing, a USB DVB-T dongle is connected to an active antenna and to the computer. As mentioned, one of the purposes is also to understand how a GPS can be implemented by software as a the substitution of a big part of the hardware that makes it impenetrable, as they are black boxes of integrated circuits, and expensive. It is known that a Global Navigation Satellite System (GNSS) software-defined open source receiver has already been created by people in Barcelona in “Centre Tecnològic de Telecomunicacions de Catalunya (CTTC)”, a testbed for GNSS signal processing since it can be customized in every way. It has been used at some intermediate steps of the study while executing parallel experiments in the course of understanding how a GPS signal is digitally processed. In the meantime, some experiments have also been performed only employing hardware before implementing them in software, so that the concepts are visually reflected. When realizing software experiments, an interface called GNURadio has been used because of its enormous implementation of signal processing blocks. GNURadio can be used with external RF hardware to create software-defined radios, or without hardware in a simulation-like environment. Nevertheless, various simulations in the GNU (Octave software environment) have also been executed as processing in real time has not been considered a goal. However, to successfully accomplish the demodulation of the navigation data, which will contribute to restore the accuracy and stability of the satellites clocks that have sent it, the carrier frequency needs to be perfectly recovered, being this last point where the final aim of the project falls on.Outgoin

Simulation of ammonia decomposition in a catalytic reaction for hydrogen production

L'objectiu d'aquest treball es dissenyar un reactor per a la descomposició d'amoníac en hidrogen i nitrogen, fent us de un material catalitzador. L'anterior per alimentar amb hidrogen una cel·la de combustible de 150 W. Addicionalment, es considera la fabricació de la malla catalitica dissenyada (part interna que esta en contacte amb fluid, on succeeix la reacció) mitjançant la impressió 3D. El material catalític considerat és Ni-Ru / CeO2 amb un 2.5% de níquel i un 0.5% de ruteni i la taxa de reacció utilitzada ésta determinada per Lucentini, García Colli, et al. (2021). El disseny, la modelació i la simulació numèrica dels reactors catalític han estat realitzades mitjançant el software COMSOL Multiphysics®. En la primera secció de l'estudi, es simula el reactor amb diferents paràmetres geomètrics, per a determinar el seu efecte en el conjunt. A la segona part, es dissenya el reactor òptim, d'acord amb la geometria definida i s’analitzar la mecànica de fluids, transferència de massa, i de calor. A l'última secció es realitza una exploració de configuracions geomètriques alternatives per a comparar el rendiment dels reactors. El disseny òptim és un reactor de 30 mm de diàmetre i 15 mm de longitud, el qual és capaç de convertir un flux d'amoníac de 53.15 g / h completament . A més, el reactor ha d'operar a una temperatura de 600 °C a la paret i el flux d’entrada ha de ser pre-escalfat a 500 °C. El objetivo de este trabajo corresponde al diseño de un reactor para la descomposición de amoniaco en hidrógeno y nitrógeno, utilizando un material catalizador. Lo anterior para alimentar con hidrogeno una celda de combustible de 150 W. Adicionalmente, el diseño de la malla catalítica (parte interna en contacto con fluido, donde la reacción sucede) considera su manufactura mediante impresión 3D. El material catalítico considerado es Ni-Ru/CeO2 con 2.5% de níquel y 0.5% de rutenio y la tasa de reacción utilizada es la determina por Lucentini, García Colli, et al. (2021). Han sido realizados el diseño, modelación y simulación numérica de reactores catalíticos usando COMSOL Multiphysics®. En la primera sección del estudio, reactores con diferentes parámetros geométricos fueron simulados, para determinar su efecto en el desempeño del reactor. En la segunda parte, se diseñó el reactor óptimo de acuerdo con la geometría definida y se analizó la mecánica de fluidos, transferencia de masa y calor. En la última sección se realizó una exploración de otras configuraciones geométricas para comparar el rendimiento de los reactores. El diseño optimo es un rector de 30 mm de diámetro y un largo de 15 mm, el cual es capaz de convertir totalmente un flujo de amoniaco de 53.15 g/h. Además, el reactor debe operar a una temperatura de pared de 600°C y el flujo entrante debe ser precalentado a 500°C.The objective of this work corresponds to the design of a catalytic reactor for ammonia decomposition into hydrogen and nitrogen, using a catalyst material. This for feed with hydrogen a fuel cell of 150W. Additionally, the design of the catalytic grid (internal part in touch with the fluid, where the reaction occurs) considers it manufacturing using 3D printing technology. The catalytic material considered is Ni-Ru/CeO2 with 2.5% of nickel and 0.5% of ruthenium and the reaction rate utilized is the one determined by Lucentini, García Colli, et al. (2021). Have been done the design, modelling and numerical simulation of catalytic reactors using COMSOL Multiphysics®. In the first part of the study, reactors with different geometrical parameters were simulated, to determine its effect on the reactor performance. In the second part, a optimal reactor was design according to the geometry defined and its fluid mechanics, heat and mass transfers. In the last section, an exploration of others geometrical configurations was done to compare the performance of the reactors. The optimal design is a 30 mm diameter reactor and a length of 15 mm, which can totally convert an ammonia flow of 53.15 g/h. Besides, the reactor must operate at 600°C at the wall and the entering flow must be pre-heated at 500°C

Health Management and Adaptive Control of Distributed Spacecraft Systems

As the development of challenging missions like on-orbit construction and collaborative inspection that involve multi-spacecraft systems increases, the requirements needed to improve post-failure safety to maintain the mission performance also increases, especially when operating under uncertain conditions. In particular, space missions that involve Distributed Spacecraft Systems (e.g, inspection, repairing, assembling, or deployment of space assets) are susceptible to failures and threats that are detrimental to the overall mission performance. This research applies a distributed Health Management System that uses a bio-inspired mechanism based on the Artificial Immune System coupled with a Support Vector Machine to obtain an optimized health monitoring system capable of detecting nominal and off-nominal system conditions. A simulation environment is developed for a fleet of spacecraft performing a low-Earth orbit inspection within close proximity of a target space asset, where the spacecraft observers follow stable relative orbits with respect to the target asset, allowing dynamics to be expressed using the Clohessy-Wiltshire-Hill equations. Additionally, based on desired points of inspection, the observers have specific attitude requirements that are achieved using Reaction Wheels as the control moment device. An adaptive control based on Deep Reinforcement Learning using an Actor-Critic-Adverse architecture is implemented to achieve high levels of mission protection, especially under disturbances that might lead to performance degradation. Numerical simulations to evaluate the capabilities of the health management architecture when the spacecraft network is subjected to failures are performed. A comparison of different attitude controllers such as Nonlinear Dynamic Inversion and Pole Placement against Deep Reinforcement Learning based controller is presented. The Dynamic Inversion controller showed better tracking performance but large control effort, while the Deep Reinforcement controller showed satisfactory tracking performance with minimal control effort. Numerical simulations successfully demonstrated the potential of both the bioinspired Health Monitoring System architecture and the controller, to detect and identify failures and overcome bounded disturbances, respectively

Association between chronic irritability and depressive symptoms in children and adolescents.

Association between chronic irritability and depressive symptoms in children and adolescents. Busto-Garrido, M.; Gutierrez-Castillo, D; Navas- Gonzalez, JR; Gutierrez-Bedmar, M; Gutierrez-Casares, JR; Martin-Lunar, MT; Rodríguez-Rosado, A; Pena-Andreu, JM. European Psychiatry 415(2017) 5221.Chronic irritability is the most frequently reported symptom in child and adolescent depression. The association of both has been linked with high rates of chronicity, comorbility and impairment. Objectives To study the association between chronic irritability and depressive symptoms in children and adolescents. Methods We have studied 857 participants recruited from the only Child and Adolescent Mental Health Clinic in a catchment area of 122968 people under 18 (2004-2010). A sample of 677 participants (57 controls and 620 patients) was included to carry out a cross-sectional study. Chronic irritability was measured by a Visual Analog Scale (VAS irritability) -scored from 0 to 10-, and depressive symptoms by the Children's Depression Inventory (CDI). The participants were categorized into controls and patients, and according to their chronic irritability (≤4 [I],5 [II] and ≥6 [III]). The mean of CDI score was calculated for each of the groups, adjusted by sex and age, and analyzed by ANCOVA. Results The following means were obtained from the controls: 13,71 (group I), 9,82 (group II) and 17,45 (group III). Regarding to the patients: 13,92 (group I), 11,54 (group II) and 15,64 (group III). A quadratic association (p <0,0015) was found between VAS irritability score and CDI score. Conclussions There is not a lineal association between chronic irritability and depressive symptoms in children and adolescent. High rates of depressive symptoms were associated both with high and low rates of irritability. Several questions remain unexplained about the status of irritability in psychiatry as Stringaris group has been pointed out. Disclosure statement I have no potential conflict of interest to discloseUniversidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Early Holocene water well in the Pampas of Argentina: Human responses to water shortage events

Water wells are ethnographically and archaeologically described in Australia and the plains of North America. Recently, a prehistoric water well from the early Holocene was recorded in the Pampas of Argentina. The aim of this paper is to present the main characteristics of the water well, considering its form, dimension, sediment analyses (texture and chemical parameters), and material culture content. This is the first water well recorded in the Pampas of Argentina. Consequently, a discussion about natural or cultural origins of this kind of features is provided. An evaluation of similarities and differences with well-described water wells from the United States and Australia is included in order to highlight the cultural origin of the pit. Also, the meaning of the cultural response to water availability in terms of early-Holocene hunter–gatherer adaptations as well as the implications of this strategy for understanding paleoenvironmental scenarios of the Pampas of Argentina are discussed. The well seems to have mitigated an exceptional lack of surface water in the eastern Pampas or offered an alternative for the non-drinkable quality of the available surface water. The strategy of digging water wells was available in the behavioral repertoire of the Pampean hunter–gatherer populations as early as c. 8700–8000 14 C yr BP (c. 9700–8800 cal. yr BP), as these groups were fairly flexible and resilient in dealing with short-term shortages of water.Fil: Martinez, Gustavo Adolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Investigaciones Arqueológicas y Paleontológicas del Cuaternario Pampeano. Universidad Nacional del Centro de la Provincia de Buenos Aires. Investigaciones Arqueológicas y Paleontológicas del Cuaternario Pampeano; ArgentinaFil: Gutierrez, Maria Amelia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Investigaciones Arqueológicas y Paleontológicas del Cuaternario Pampeano. Universidad Nacional del Centro de la Provincia de Buenos Aires. Investigaciones Arqueológicas y Paleontológicas del Cuaternario Pampeano; Argentin

Prototipo de vivienda de adobe con energías renovables: caso de estudio localidad de Raíces, Área Natural Protegida del Parque Nacional del Nevado de Toluca, Estado de México

Como una alternativa a la construcción de la vivienda, este artículo introduce una nueva tecnología para edificar un prototipo de casa de adobe con energías renovables. Se muestrauna metodología para su diseño que se establece a partir de las características de las viviendas de la localidad de Raíces, ubicada en el municipio de Zinacantepec, dentro del territorio del Parque Nacional del Nevado de Toluca, espacio natural protegido por Decreto en 1936

LANDREC, A Set of Interactive Microcomputer Programs Used as a Help on Land Reclamation Projects

This paper deals with LANDREC software which was built for helping in land reclamation and landscape restoration. This program is compound by three modules: EVALUATION, INTMOREINF and INTEGRATION. The first module provides a optimal solutions for lands to be rehabilitated by considering scenic, topographic and economical aspects, the approach is based on linear programing transport algorithm. The second module allow to enter information from nearby areas in order to quantify the influence of the rehabilitation. The third module, called INTEGRATION, test all model to find the best. The paper includes a case-study located in the valley of Jarama (Madrid, Spain) where gravel extraction for construction has produced a deep deterioration in fluvial landscapes

Impacto del Comercio Justo en el desarrollo de los Productores Asociados a La Cooperativa “La Providencia” durante el Segundo Semestre del Año 2011

Se analizó el impacto del comercio justo en el desarrollo de los productores asociados a CECOCAFEN durante el segundo semestre del 2011, este trabajo está compuesto por tres variables de acuerdo al objetivo general y a los específicos, la primera variable trata de describir el sistema de Comercio Justo, a través de la producción, de los mecanismos de certificación, de las técnicas utilizadas para la comercialización, mediante algunas políticas económicas implementadas por el gobierno y señalando también el origen de otros ingresos, dando como resultado que el producto que se comercializa está debidamente certificado a través de distintas técnicas ya sean estas artesanales o semitecnificadas, a la vez estos obtienen ingresos por la comercialización de granos básicos y ganado entre los más relevantes. La segunda variable evalúa el funcionamiento de las cooperativas, a través de la participación de los socios en las asambleas y así también en la toma de decisiones en cuanto a la distribución económica por excedente se refiere, donde se puede constatar que la asociatividad es una alternativa para el cooperativismo ya que se practican cada uno de los valores y principios dentro de esta cooperativa funcionando como un ejemplo al cooperativismo. La tercera variable identifica el impacto del comercio justo en el desarrollo de los productores, explicando así las necesidades básicas de los asociados donde de cierta forma el impacto del comercio justo tiene efectos negativos ya que este mide el crecimiento y no el desarrollo de los productores, pudiendo observar que estos cuentan con muchas necesidades insatisfechas y destinan parte del incentivo para estas necesidades pero no se pueden cubrir en su totalidad, tampoco cuentan con el apoyo de la cooperativa para dichas necesidades, quizás esto se debe a que la cooperativa no cuente con un fondo para suplir los gastos que generaría diversos proyectos para el desarrollo de los productores, pudiéndose constatar que el efecto positivo para los asociados viene siendo el incentivo recibido por la comercialización de su producto que es la fuente de ingresos y subsistencia para su famili

Mobile Usability: An Experiment to Check Whether Current Mobile Devices are Ready to Support Frames and iFrames

Frames have traditionally been identified as a usability issue in websites for computers. Literature points out that they may also be a problem for mobile websites but no studies have been carried out to prove it. Since mobile devices have changed a lot in recent years, it is necessary to check whether frames are still a problem for those devices. In this paper we have performed an experiment with twenty-two mobile devices, to test whether the content can be showed in their browsers, as well as their behavior with different configuration of frames and iframes and whether behavior of bookmarks and the back button is correct or not. The results show that frames and iframes should be avoided in mobile devices because they can cause many problems, which are explained in detail in this paper