116 research outputs found
Análisis sobre la influencia de la densidad en la termografía de infrarrojos y el alcance de esta técnica en la detección de defectos internos en la madera
This paper shows the results of a laboratory phase for
the determination of the 1limits of infrared thermography
in detecting internal defects in wood and, furthermore, it
analyses how the density of this material can influence
the surface temperature displayed in a thermogram. To
this end, experimental work is carried out whereby a
series of work and environmental parameters are
monitored (such as environmental temperature, relative
humidity, distance to target), and the process is
systematized by using pieces of different wood species
(different densities) and by devising a set of samples for
which various possible cases are analysed in terms of
size and internal position of the damage. Similarly, using
these samples, a study has been conducted on the effect
on the thermal image produced by an increase of
humidity inside the defect phenomena normally
associated with wood decay.En el presente artículo se muestran los resultados obtenidos
en una fase de laboratorio al tratar de determinar
el alcance de la termografía de infrarrojos en la detección
de defectos internos en la madera y, por otro lado,
cómo interviene la densidad de este material sobre la
temperatura superficial mostrada en un termograma.
Para ello se ha desarrollado un trabajo experimental
donde se han controlado una serie de parámetros
ambientales y de trabajo (temperatura ambiente, humedad
relativa, distancia al objetivo…), y se ha sistematizado
el proceso utilizando piezas de distintas especies
de madera (distintas densidades) y diseñando una serie
de probetas donde se han analizado varias casuísticas
posibles en cuanto a tamaño y posición interna de los
daños. Análogamente, sobre estas probetas se ha estudiado
el efecto que produce sobre la imagen termográfica
un incremento de humedad interna en el defecto
asociada normalmente a los fenómenos de pudrición de
la madera
Characterisation of recycled ceramic mortars for use in prefabricated beam-filling pieces in structural floors
This study analyses a procedure to manufacture mortars with different percentages of ceramic waste as partial replacement for aggregates. The study also examines the physical, chemical and mechanical properties of the new mortars, analysing substitution ratios that range from 10% to 50%. Prior to this, all the materials used in the production of the mortar were characterised using X-ray diffraction (XRD) and fluorescence (XRF). The objective was to determine the similarity between different types of ceramic waste, as well as the differences in the minerology and chemical composition with the aggregate.
The results of the study show that it is possible to obtain mortars with lower densities compared to the same product with no recycled content. The product’s characteristics make it ideal for the manufacture of prefabricated components for structural floors for rehabilitation works. Finally, the pieces are used in a real rehabilitation case study, highlightining the structural advantages.Caracterización de morteros con cerámica reciclada y su uso en piezas prefabicadas para entrevigado de forjados. Este trabajo analiza morteros con diferentes porcentajes de cerámica reciclada como sustituto parcial de la arena. Además el estudio examina las propiedades físicas, químicas y mecánicas de los nuevos morteros, empleando diferentes porcentajes de sustitución (10% - 50%). Con anterioridad, se caracterizaron todos los materiales empleados en este trabajo mediante difracción y fluorescencia de rayos-X. El objetivo fue determinar las diferencias y similitudes en la composición química y mineralógica de los distintos tipos de residuos cerámicos y del resto de áridos utilizados.
Los resultados muestran que es posible obtener morteros con menor densidad frente a las muestras sin contenido reciclado. Sus características los hacen idóneos para la creación de piezas prefabricadas de entrevigado para rehabilitación de forjados. Finalmente. Las piezas se usaron en un caso de estudio real, destacando las ventajas estructurales que conlleva su uso
Impact of Wetting–Drying Cycles on the Mechanical Properties and Microstructure of Wood Waste–Gypsum Composites
Large amounts of wood waste are generated each year in the world. In an attempt to identify
a good recovery option for those residues, wood waste from construction and demolition works were
used as raw materials in gypsum plasters. However, wood is a biodegradable material which implies
that the products or materials that contain it are susceptible to su ering an important deterioration,
due to exposure in certain environments. For that reason, the aim of this work was to simulate the
e ects that, in the long term, the atmospheric exposure of wood waste–gypsum composites would
have. To do that, the plasters were subjected to 5, 10, and 15 wetting–drying cycles in a climatic
chamber. In this study, the density, flexural and compressive strength, and ultrasonic velocity of these
composites were determined by the influence of the aging process on their mechanical properties.
Furthermore, in order to detect changes on their internal structure, scanning electron microscopy
tests (SEM) were used. The results showed that they were suitable to be used as indoor coverings
of buildings. However, a treatment to reduce the moisture absorption of the wood waste must be
studied if mixtures with high percentages of wood shavings (WS20) are used in wet rooms
Implementación de la aplicación web de la Asociación de Telemática (ATEL)
El objetivo de este Trabajo de Fin de Grado es diseñar e implementar la aplicación web de la Asociación de Telemática (ATEL), que va a sustituir a la que está actualmente en funcionamiento. La aplicación desarrollada está dotada de mayor seguridad, cumpliendo así la legislación vigente. Para actualizarla, también contiene funcionalidades nuevas y un diseño adaptable a todo tipo de dispositivos, mediante Bootstrap. Además, se ha realizado un programa que permite la migración de la antigua base de datos a la nueva de forma rápida y cómoda.
Esta aplicación incluye tres áreas. La primera es pública, para usuarios no registrados. Las otras dos son zonas privadas con un filtro que sólo permite el acceso a los socios o administradores registrados previamente. La arquitectura de diseño utilizada es el patrón Modelo-Vista-Controlador, eligiendo como lenguaje de programación Java EE. Se ha empleado una base de datos MySQL. En el desarrollo, ha sido muy importante utilizar un tratamiento seguro de los datos sensibles de los socios y administradores con técnicas novedosas y fiables. Por otra parte, se ha integrado como plataforma de pago PayPal.
Por último, se ha intentado facilitar a los futuros desarrolladores la realización de mejoras, documentando adecuadamente el código escrito y redactando una memoria de desarrollo para ATEL.The aim of this Bachelor Thesis is to design and implement the web application of the Association for Telematics (ATEL), which is going to replace the one that works at present. The developed application has been supplied with a stronger security for fulfilling the requirements of the current legislation. It also has new functionalities and a responsive design by using Bootstrap. This crafts the site to provide an optimal viewing experience across a wide range of devices. Besides this, a program has been made to enable fast and easy migration from the old database to the new one.
This application includes three areas. The first one is public and intended for no registered users. The other two are private parts that include a filter that only allows members or administrators previously registered to access. The architectural pattern is Model-View-Controller, using Java EE as the programming language and a MySQL database. During the development, a secure data treatment by means of innovative and reliable techniques has been essential. In addition to this, a payment gateway with PayPal has been integrated.
Finally, efforts have been made to make the implementation of new functions and improvements to future developers easier. The code has been properly documented and a development manual has been written for ATEL.Ingeniería en Tecnologías de Telecomunicació
Electrospray deposition: a breakthrough technique for proton exchange membrane fuel cell catalyst layer fabrication
This Spotlight article presents the state-of-the-art of electrospray deposition technique applied to the fabrication of proton exchange membrane fuel cell (PEMFC) components, mainly focusing on catalyst layers in gas diffusion electrodes. The atomization of a suspension of particles over a substrate under the influence of a strong electric field results in the growth of a film with macroporous morphology and many interesting properties. This so-called electrospray deposition has reported many noteworthy beneficial effects for the fabrication of the catalyst layers of gas diffusion electrodes of PEMFCs. The electrosprayed catalyst layers prepared from suspensions of catalyst particles and ionomers present a dendritic macroporous morphology with superhydrophobic character that improves the water management inside the cell and increases the performance by ∼20% with respect to standard electrodes prepared by airbrushing. Other interesting effects observed with electrosprayed catalyst layers are increased catalyst utilization and water absorption capabilities of the ionomer, improved performance under nonhumidified conditions, and a reduction in catalyst degradation. In addition, the electrospray deposition decreases platinum losses during fabrication thanks to the attractive electrostatic forces between the ion mist and the substrate compared with regular ink-based spray methodsThe work is partially financed by the ELHYPORT project (PID2019–110896RB-I00), Spanish Ministry of Science and InnovationS
Entre Amazonas y Grifos. Viaje por las imágenes de frontera en el siglo IV a.C.
The Amazon imagery started population Greek vases at the end of the VII century B.C. Being of a polysemic nature, they personify the absolute otherness for the ideal Greek citizen, due to their representation of all the antithetical values: they are women, barbarian, undomesticated. Through the following centuries they are endowed with new meanings, especially in the IV century B.C., a time of profound geopolitical changes. The graphical representation of the struggle for the control of gold between Arimaspi, fierce one-eyed warriors, and Gryps, fearsome hybrid beings that extract it from the earth and guard it, starts towards the end of the vi century B.C., but it will also become a favourite theme of the Greek painters in the iv century B.C., mainly intended for the peripheral areas. We analyze the distribution area of vases decorated with both themes at both ends of the Mediterranean, and its meaning. Amazonomachy and Grypomachy, frontier imagery, seem to act as essential elements in the building of the Greek identity.La imagen de las Amazonas comienza a poblar los vasos griegos desde fines del siglo VII a.C. De naturaleza polisémica, encarnan la alteridad absoluta para el ideal ciudadano griego, pues representan todos los valores antitéticos: son mujeres, bárbaras, no domesticadas. A lo largo de los siglos se dotan de nuevos significados, especialmente en el siglo IV a.C., época de profundas mutaciones geopolíticas. La representación de la lucha por el control del oro entre Arimaspos, feroces guerreros de un solo ojo y Grifos, temibles seres híbridos que lo arrancan de la tierra y custodian, nace a fines del siglo VI a.C. pero será también en el siglo IV a.C. cuando se convierta en un tema predilecto de los pintores griegos, destinado a las áreas periféricas. Analizamos el área de distribución de los vasos decorados con ambos temas en los dos extremos del Mediterráneo y su significado. Amazonomaquias y Grifomaquias, imágenes de la frontera, parecen actuar como elementos indispensables en la construcción de la identidad griega
Inspección with non destructive techniques of a historic building: oratorio San Felipe Neri (Cádiz)
El objetivo de este artículo es dar a conocer
los resultados obtenidos al aplicar técnicas no
destructivas de inspección (ultrasonidos y termografía)
durante las obras de reparación de
un edificio de gran valor histórico y artístico.
Estas técnicas no destructivas se han aplicado
en la inspección de la cubierta de madera del
edificio para detectar distintos estados de deterioro,
pérdidas de densidad y defectos, con el
objetivo de evaluar su estado de conservación.
Se ha realizado un trabajo de campo donde
se ha aplicado ambas técnicas conjuntamente,
los ultrasonidos, técnica eficaz para establecer
el diagnóstico de una estructura de madera, y
la termografía, técnica menos experimentada
en la inspección in situ de este material. El
objetivo es acotar el alcance y las posibilidades
reales de utilización de cada una de las técnicas.
En este sentido, se aplica la metodología
de ultrasonidos desarrollada y publicada por
las autoras y se estudia la termografía como
herramienta de inspección in situ analizando
las dificultades añadidas y parámetros de interferencia
no detectados en laboratorio.
Las conclusiones del trabajo ponen de manifiesto
que la unión de la técnica de ultrasonidos
y la termografía constituyen una buena
herramienta para la inspección in situ de las
estructuras de madera y para evaluar sus condiciones
permitiendo establecer un diagnóstico
adecuado. La termografía permite detectar
distintos contenidos de humedad y distintos
materiales y, por otro lado, los ultrasonidos
los distintos grados de deterioro o pérdida de
densidad en zonas localizadas con elevado
contenido de humedad de las piezas.The main aim of this article is showing the
results that have been obtained when non
destructive techniques (ultrasound and thermography)
are applied to a building with an
important artistic and historical value.
These non-destructive techniques have been
applied in the inspection of the wooden roof
structure to detect different states of deterioration,
loss of density and defects. The aim is
the assessment the state of the preservation of
the wooden structure. A fieldwork has been
carried out, where the two techniques have
been applied together, ultrasound, an effective
technique to establish the diagnosis of a
wooden structure, and the thermography, a
technique less tested in the in situ inspection
of this material. The aim is checking the range
and the real possibilities of using of each
technique. In this sense, the methodology of
ultrasound developed and published by the
authors is applied and the thermography like
in situ inspection tool, analysing additional
difficulties and interference parameters not
found in laboratory.
The conclusions of this study show that
the union of the ultrasound technique and
the thermography is a good tool for on-site
inspection of wooden structures and to assess
their conditions allowing establishing a
proper diagnosis. Thermography can detect
different moisture contents and different
materials and, on the other hand, ultrasound
detects different states of deterioration or
loss of density in specific areas with a high
moisture content of the piece
Forjados de madera de entrevigado cuajado con residuos cerámicos de demolición
The present work is the continuity of the research carried out by the group TEP 205,
"Analysis and evaluation of construction and structural systems in Architecture", focused on domestic architecture building typologies of cities as Seville or Cordoba from the seventeenth to the twentieth centuries.
The aim of the study, mainly experimental, is to develop a new infill piece, from the reuse of ceramic waste generated in demolition works. This piece is intended to be used in the floors of this building typology.
Different test models reproducing the geometry and structural characteristics of these slabs have been developed. In these models different dosages of mortars and geometries are studied, in order to achieve the necessary strength for their use on the building site. As a result, we have developed a piece in which resistance values reaches up to 137 Kgf, higher than the values required to prefabricated concrete slabs according to regulations.El trabajo realizado es una continuidad en la línea de investigación del grupo TEP-205,
“Análisis y evaluación de sistemas constructivos y estructurales en la Arquitectura”, centrada en las tipologías edificatorias de la arquitectura doméstica de ciudades como Sevilla o Córdoba de los siglos XVII al XX.
El objeto del trabajo, fundamentalmente experimental, consiste en desarrollar una nueva pieza de entrevigado, a partir del reaprovechamiento de los residuos cerámicos generados en las tareas de demolición. Esta pieza está destinada a emplearse en los forjados de entrevigado cuajado característicos de esta tipología edificatoria.
Para la definición de este elemento se han elaborado diferentes modelos de ensayo
reproduciendo la geometría y características constructivas de estos forjados. En estos
modelos se estudian diferentes dosificaciones de morteros y geometrías, en aras de
alcanzar la capacidad resistente necesaria para su utilización en obra. Como esultado, se ha desarrollado una pieza en la que se alcanzan valores resistentes de hasta 137 Kgf, superiores a los valores exigidos a las bovedillas prefabricadas de hormigón según normativa
Management skills and leadership behavior. An experience in the classroom in the training of social educators
La actividad que se expone va dirigida a la formación de las futuras Educadoras y
Educadores Sociales. Se establece que se hace necesario el desarrollo de competencias
personales y profesionales, haciendo más activo el papel del alumnado y desarrollando la
capacidad de analizar las habilidades directivas y conductas de liderazgo como
instrumento de reflexión. La actividad se centra en un aspecto de la Educación Social, las organizaciones
socioeducativas, y dentro de ellas, el estudio de las habilidades directivas y conductas de
liderazgo. La formación en las habilidades directivas y conductas de liderazgo desde el
propio trabajo de campo del alumnado a través de entrevistas supone iniciarse tanto en el
ámbito investigativo como prepararse para el desarrollo de la actividad profesional. Es por
ello que la preparación que se adquiere en este proceso formativo permite al alumnado
demostrar su competencia en la actividad práctica de recogida de datos en el contexto de las organizaciones socioeducativasThe activity that is exposed is directed to the formation of the future Educators and Social
Educators. It is established that it is necessary to develop personal and professional skills,
making the role of students more active and developing the ability to analyze leadership
skills and leadership behaviors as an instrument of reflection. The activity focuses on one
aspect of Social Education, socio-educational organizations, and within them, the study of
managerial skills and leadership behaviors. Training in managerial skills and leadership
behaviors from students' own fieldwork through interviews supposes starting both in the
research field and preparing for the development of professional activity. That is why the
preparation that is acquired in this training process allows students to demonstrate their
competence in the practical activity of data collection in the context of socio-educational
organizations. That is why the preparation that is acquired in this training process allows
students to demonstrate their competence in the practical activity of data collection in the
context of socio-educational organization
Reuse of CD and DVD wastes as reinforcement in Gypsum Plaster Plates
The continuous and rapid evolution in the field of computing, and in particular in the field of storage devices, has led to the obsolescence of optical discs in favour of mass storage devices.In that sense, a large number of CDs and DVDs become obsolete each day in the world. In trying to create a recovery solution for those pieces, research in which polycarbonate (PC) waste from recycled discs have been used to develop new gypsum coating materials and products has beenconducted. In a previous study, the physical and mechanical properties of new gypsum plasters, with PC waste as aggregate, were studied. Following that study, this article aims at creating new gypsum plaster false ceiling plates, using CD and DVD residues in different scenarios: as crushed aggregatein the gypsum matrix, as full reinforcement pieces of the plates and as a combination of both. The mechanical behaviour and the thermal conductivity of the new pieces have been analysed in this paper. The results showed an important improvement in the mechanical and thermal properties ofthe plates when the PC waste was used in many scenario
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