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Ciberviolencia sexual: investigación y prueba
Get PDFMención Internacional en el título de doctorPrograma de Doctorado en Derecho por la Universidad Carlos III de MadridPresidenta: Silvia Barona Vilar.- Secretaria: Sabela Oubiña Barbolla.- Vocal: Pedro Miguel Freita
Regulatory solidarity and fundamental rights in the Schengen Borders Code
No full textEl presente trabajo examina el respeto de los derechos fundamentales en el ámbito del Código de Fronteras Schengen (CFS). Primeramente, a la luz del statu quo actual, jurisprudencial y normativo. A continuación, se examina el impacto de la COVID-19 y de las medidas, carentes de precedentes, y sin bases jurídicas claras, que hubieron de improvisarse contra la pandemia y que repercutieron de lleno sobre el CFS (cierre de las fronteras exteriores, restablecimiento de controles en las interiores y prohibiciones cambiantes de desplazamientos «intra- Schengen») y sobre los derechos fundamentales. Por último, y también desde la perspectiva del respeto de los derechos fundamentales, se aborda la incidencia del Nuevo Pacto sobre la Migración y el Asilo sobre el CFS, a través de la propuesta de modificación del CFS presentada por la Comisión y actualmente en trámite.This paper examines the respect for fundamental rights within the scope of the Schengen Borders Code (SBC). Firstly, it does so in the light of the current status quo, jurisprudential and normative. It then surveys the impact of COVID-19 and of the unprecedented measures, with no clear legal basis, that had to be improvised against the pandemic and which had a major impact on the SBC (closure of external borders, reintroduction of internal border controls and changing prohibitions on “intra-Schengen” movements) as well as on fundamental rights. Finally, and also from the perspective of respect for fundamental rights, the impact of the New Pact on Migration and Asylum on the CFS is addressed, through the proposal for amendment of the CFS presented by the Commission, currently under consideration.Lan honetan, Schengen Mugen Kodearen (SMK) eremuan oinarrizko
eskubideak zenbateraino errespetatzen diren aztertzen da. Lehenik eta
behin, oraingo —jurisprudentziako eta arauzko— statu quo-aren argitara egiten da analisia. Gero, COVID-19aren inpaktua aztertzen da, bai eta pandemiaren aurka inprobisatu behar izan ziren eta SMKn eta oinarrizko eskubideetan bete-betean eragina izan zuten neurriena ere, aurrekaririk eta oinarri juridiko argirik gabeak horiek (kanpo-mugak itxi ziren, barne-mugetan kontrolak berrezarri ziren, eta «Schengen barruko» lekualdaketak debekatu ziren, debeku aldakorren bidez). Azkenik, oinarrizko eskubideekiko errespetuaren ikuspegitik ere heldu zaio migrazioari eta asiloari buruzko itun berriak SMKn duen eraginari, batzordeak SMK aldatzea proposatu baitu eta, gaur egun, aldaketa hori izapidetzen ari baita.El presente trabajo es resultado del Proyecto Nacional de I+D «El Espacio de libertad, seguridad y justicia en tiempos inciertos: futuro y retos jurídicos (ELSJFREE)», PID2021-128195NB-I00
Study and development of optical frequency combs to demonstrate their technical feasibility in the aeronautical field
No full textThe idea or the concept of autonomy, today, is inextricably tied up with the one of progress. The world is evolving rapidly, demanding greater autonomy in its processes, applications, services, products... and these demands come from both sides: the commercial and military world. The present research work supports this exploration, analyzing the current state of the technologies used in aeronautics for absolute and relative positioning, and reviewing the evolution of the technical availability of architectures based on optical frequency combs (OFCs) to provide aircrafts with advanced features toward the desired autonomy. In this direction, this thesis presents a new architecture for relative positioning measurements based on advanced optical sources as optical frequency combs has been carried out through a theoretical analysis, a laboratory characterization and, finally, through a validation of the system in a relevant environment. The viability of the new approach presented in this thesis has been confirmed by flight tests (outdoors) using a drone and demonstrating that the precision in measuring the relative distance between transmitter and receiver is greater than that required by aeronautical applications today. However, further developments would be required to obtain a system that could be finally integrated in final products. Finally, this thesis abounds in the fact that the state of the art of aeronautical applications present a gap between what exists today on board of an aircraft and the actual requirements for the desired autonomy strategy in the aerospace field, so it has value and sense to continue researching in this type of technology.Programa de Doctorado en Ingeniería Eléctrica, Electrónica y Automática por la Universidad Carlos III de MadridPresidente: José Antonio García Souto.- Secretaria: Estefanía Prior Cano.- Vocal: Ángel Rubén Criado Serran
Estudio y diseño de nanoestructuras para mejorar las caracteristicas de dispositivos fotónicos de última generación
Get PDFMención Internacional en el título de doctorLike any high-tech sector, photonics must innovate to survive. In this sense, the increasing generation of products and integrated devices combining lasers, sensors, and optics opens new opportunities in the field of photonics. Meanwhile, nanotechnology has emerging as a powerful field with interesting applications in various industries, especially in photonics and materials engineering. Nanotechnology has served as a catalyst to unlock the full potential of photonics by enabling the fabrication of materials and structures at the nanometer scale. Nanostructures are emerging as important components in the development of advanced electromagnetic and optical devices. The manipulation of electromagnetic waves and photons at the nanoscale has opened new avenues for breakthrough technologies. Nanostructures are typically characterized by dimensions on the order of nanometers and exhibit unique properties that allow precise control of the interaction of electromagnetic fields and matter. As research in this field advances, nanostructures are expected to play an increasingly role in shaping the future of photonics. Some of its key applications are related with optical communications, non-linear photonics, light management, light harvesting or nano-sensing, among others. In particular, this work is focused on three of them: solar cells, enhanced LEDs, and all-optical sensors. Current high-efficiency solar cells are usually use the unique optical properties of nanomaterials (e.g. quantum dots, nanowires, etc.) as an immense potential to increase their efficiency. This is because these materials allow not only a better light absorption in an active region but also reduce energy losses and improve the mobility of charge carriers, resulting in solar panels with a significant boost in energy conversion due to the incorporation of nanotechnology in their design. Light-emitting diodes (LEDs) enhanced with nanostructures that feature improved efficiency, color rendering and durability due to the integration of nanomaterials, such as nanophosphors, quantum dots and plasmonic nanostructures, creating vibrant and environmentally friendly lighting solutions. Optical sensors, which use nanostructured materials such as plasmonic nanoparticles, have significantly increased sensitivity. This allows detecting and analyzing a wide range of substances with high specificity and ultra-low detection limits. This has important implications, especially for environmental monitoring, biomedical diagnostics, and food safety. The aim of the present PhD thesis is, in the frame of this research field, to study and propose new designs and devices based on nanostructures with the aim of improving the characteristics of state-of-the-art photonic devices. As an initial phase, a search for information on the state of the art about light-matter interaction at the nanoscale and metamaterials were made; as well as areas of application of three-dimensional nanostructures in solar cells, LEDs, sensors, information transmission systems, etc., was performed. A review of the fundamental theory of electromagnetics and the numerical simulation methods used was also given.The following is a summary of the three main chapters of this document of this document, which present the main case studies analyzed and the corresponding results obtained. Complex areas such as space applications or embedded devices require low-cost and simple solar cells. Reducing the thickness of the active layer (thin-film devices) is the traditional approach to meeting both requirements. However, it reduces the efficiency of
the device. In the last few years, nanostructures have become a crucial alternative in the design of advanced photovoltaic devices. In Chapter 3, the optical properties of several groups of semiconductor nanoparticles on the surface of thin GaAs solar cells will be studied to enhance the light absorption in the active layer, considering an AM-1.5 solar spectrum standard. A unit solar cell is presented, which arrangement, materials in the different layers, and geometrical (diameter, thickness, and the period of the nanoparticles array) parameters has been considered to provide a convenient reference which efficiency has been also evaluated using plasmonic nanoparticles. The model used the Finite Element Method (FEM) implemented by COMSOL Multiphysics to simulate the optical behavior
of the device and the absorption rate of each layer. Two other systems were also considered for comparison. One is a GaAs solar cell with the same geometrical properties and material composition as the previous one, but without optical trapping technology, the other, like the latter, includes a typical antireflection coating (ARC) GaAs solar cell made of magnesium fluoride (MgF2) and zinc sulfide (ZnS). The numerical results were compared with other concepts such as localized surface plasmon resonances in aluminum nanoparticle arrays and conventional solar cells with or without anti-reflective coatings (ARC). The inclusion of semiconductor nanoparticles (NPs) showed better response of solar cells at different rates compared to solar cells with ARC. Moreover, the efficiency increases a 10% compared to aluminum nanoparticles structure (NPs) and a 21%and a 30%considering the conventional solar cells and without ARC, respectively. Furthermore, nanostructures have significantly improved the sensitivity and specificity of sensors and detectors. The ability to detect subtle changes in the environment is critical for healthcare, environmental monitoring, and security applications and enables the development of more accurate and reliable systems. In this regard, in Chapter 4 we consider the design of an optical system based on two identical silicon nanowires that support different optical resonances in the infrared range and serve as the basis for an optical sensor. The main objective of this study was to design and characterize an alloptical sensor for mechanical displacement detection using resonant nanostructures. The system is based on the observation that excited resonances cause a significant increase in the scattered field near the field near the nanowires. Therefore, a variation in the distance between the nanowire, and the consequent interaction between them, will produce a detectable change in the spatial distribution of this scattered field. It is important to note
that the conditions that produce these resonances are highly dependent on the surrounding medium. The effect of the distance between nanowires is analyzed. The simulation model is based on the finite element method using the COMSOL Multiphysics software. The diameter of the nanocylinder (d = 140 nm) was previously adjusted to achieve a resonant effect at commercial wavelengths (λ = 1064 nm and 1310 nm). These results indicate significant changes in their optical properties and optical interaction. The purpose of this design is to use a laser diode as a simple light source and simplify the illumination process, with sensitivities of 8.67 · 105 V/m2 and 1.14 · 106 V/m2 at 1064 nm and 1310 nm, respectively. These results provide the opportunity to explore other motion or vibration
sensors from an optical perspective and evaluate their applications. Going further from a numerical design to a pre-industrial application, this chapter is focused on a Visible Light Communication (VLC) system. Currently, the indoor positioning systems (IPS) have become a topic of great interest among researchers. On the other hand, VLC systems have advantages over RF technology. For example, they do not require satellite signals or lack electronic interference to reach a location. Nowadays, in the context of Indoor Positioning (IPS), Visible Light Positioning (VLP) systems are a strong alternative to RF-based systems, reducing costs and time to market. Section 5.1 introduces low-cost VLP solutions for indoor systems. These include multiple programmable beacons and a receiver which can be plugged to a smartphone running a specific app. Location information is transmitted quickly and securely between the receiver and the configurable LED-beacon that can be placed at that location. Implementation is simple, low-cost, and does not require a direct connection to a data server. With recent advances in information technology, speed has become an important requirement for data transmission. In recent years, the rapid development of solid-state light-emitting diode (LED) materials has enabled the next generation of 5G data communications. Considering that LEDs can turn on and off thousands or even millions of times per second, LiFi (Light Fidelity) technology is faster than WiFi (Wireless Fidelity) in terms of speed. Light fidelity that holds the key to solving the challenges of 5th and higher generation mobile networks. LiFi is a two-way wireless communication technology that enables high-speed uplink and downlink communication at the same time. Currently, due to increasing demand from internet users, researchers, and manufacturers are considering LiFi technology as an essential solution to the limitations of the radio frequency (RF) spectrum. Additionally, the integration of various communication technologies such as Wireless Fidelity (WiFi) and LiFi can help address the traffic restriction challenges caused by the increasing demands of Internet users. Although LiFi offers highspeed data transmission capabilities, it has some weaknesses such as coverage. Therefore, a hybridWiFi/LiFi network can take advantage of high-speed data transmission from LiFi and wide coverage from WiFi. LiFi transmits data 10 000 times faster than radio waves and is secure and free from electromagnetic interference. Integrating these technologies compensates for the shortcomings of each technology and improves network performance. In Section 5.2 we present the design of a system for the provision and consumption of HD multimedia content for public transport based on LiFi technology. A miniaturized prototype consisting of a stack of three boards was created, allowing a visible link bandwidth of 15 MHz and an infrared link bandwidth of 18 MHz at a distance of 110 cm. We have shown that LiFi data transmission is feasible and high-resolution video was transferred successfully. The thesis will end with a summary of the results and main conclusions of this work. It also points out several ideas that may form the basis for future studies and research that will follow on from the present one.Programa de Doctorado en Ingeniería Eléctrica, Electrónica y Automática por la Universidad Carlos III de MadridPresidenta: Beatriz Romero Herrero. - Vocal: Bennis Noureddine.- Secretaria: Cristina de Dios Fernández
Strategic use of social media influencer marketing
Get PDFWe set out a model of social media influencer marketing in which a firmmay hire influencers to inform consumers about an innovation. Influencersgenerate sales through purchases of their followers and followers' social networks and set prices for their endorsements. In turn, the firm decides whichinfluencers to hire, which story to convey via the influencers, and sets the retail price of the innovation. In equilibrium, influencers price according totheir marginal contribution to industry profits and increase consumers' willingnessto pay with their stories. In particular, under a weak condition itis the influencers with the most reactive followers who are hired and obtainpositive profits in equilibrium. Finally, we show that the firm may be betteroff if it could commit to hire fewer influencers.Fernando Vega-Redondo acknowledges financial support by grant CEX2021-001181-M financed by MICIU/AEI /10.13039/501100011033, María Zambrano Program 2021, and Comunidad de Madrid, grant EPUC3M11 (V PRICIT)
Aristocracia y representación del Estado Moderno. Una historia social de la diplomacia a partir de los embajadores españoles en Francia en el reinado de Felipe IV (1621-1665)
Get PDFMención Internacional en el título de doctorPrograma de Doctorado en Humanidades por la Universidad Carlos III de MadridPresidente: Enrique Villalba Pérez.- Secretario: Antonio Álvarez-Ossorio Alvariño.- Vocal: Alexandra Merle Micho
Generación de Microondas mediante Técnicas basadas en Fotónica Integrada para Cargas de Pago Satelitales Flexibles
No full textESta Tesis doctoral realiza un estudio entre las distintas técnicas de generación de frecuencia en rango de microondas y milimétricas basadas en técnicas fotónicas, para encontrar la que más se adecue al campo de las Comunicaciones Satélite. Más específicamente, para cargas de pago útiles de alto rendimiento. La Tesis focaliza principalmente en sistemas que sean capaces de ser integrados en chip como parámetro clave. Se presentarán algunas de las estructuras basadas en láseres de semiconductor integrados más novedosas de la última década, con las que se pretende la generación de radiofrecuencia en las bandas Ka(25 GHz), Q(32 GHz) y V(50 GHz), como bandas de interés. Estás estructuras de láseres tienen como punto fuerte la capacidad de sintonización. Pueden cubrir todo el rango de microondas y milimétricas, manteniendo un tamaño, peso y consumo reducidos. Este factor supone una gran ventaja con respecto a los sistemas de radiofrecuencia convencionales. El mayor inconveniente es la estabilidad de la señal generada. La tesis propone un estudio de tres técnicas de generación basadas en láseres monomodo, láseres pulsados y láseres de cavidad extendida. Los láseres monomodo se han planteado desde el punto de vista de la utilización de distintas plataformas de integración, como el fosfuro de indio monolítico y el fosfuro de
indio con polímero híbrido. Como figuras de mérito, utilizando láseres de semiconductor fabricados en fosfuro de indio monolítico se ha reportado una estabilidad de portadora eléctrica a 21 GHz de 300 MHz en 5 minutos de medida. Utilizando láseres de semiconductor en la plataforma híbrida de fosfuro de indio con polímero con una estabilidad de portadora eléctrica a 23 GHz de 120 MHz en 5 minutos de medida. Se ha planteado el uso de láseres pulsados para aumentar la estabilidad de la señal generada. Se ha utilizado una estructura láser conocida como láser de mode-locking. Mediante este dispositivo se ha reportado estabilidad de señal generada a 33 GHz de 2 MHz en 5 minutos de medida. Y por último, utilizando láseres integrados de cavidad extendida fabricados en una plataforma híbrida de fosfuro de indio con nitruro de silicio se ha reportado la estabilidad de señal generada a 25 GHz menor de 30 MHz en 10 horas de medida, siendo la opción que más se ajusta de las tres estudiadas. En esta tesis, se analiza también la técnica de generación basada en modulación externa como alternativa a la generación de frecuencia puramente con láseres. Se ha analizado desde el punto de vista integrado donde se ha demostrado la generación de señal desde DC hasta 16 GHz en un chip fabricado en la plataforma integrada de fosfuro de indio. Para compensar las limitaciones en frecuencia de la plataforma de integración se ha planteado la implementación utilizando componentes discretos donde se ha demostrado la generación de señal desde DC hasta 100 GHz utilizando esta técnica. Finalmente, se presenta el proyecto THORMUX. Proyecto financiado por la Agencia Espacial Europea (ESA) que fue concebido a raíz de los resultados obtenidos durante el desarrollo de esta tesis. Su principal objetivo es la implementación de un multiplexor/ demultiplexor fotónico capaz de trabajar en las bandas Ka, Q y V. Se presentarán
algunos de los resultados preliminares obtenidos durante las primeras fases del proyecto y las líneas futuras a seguir.TH I S Doctoral Thesis performs a study among the different techniques of frequency generation in microwave and millimeter-wave range using photonic based-on techniques, to find the most suitable one for Satellite Communications (SatComs). More specifically, for high throughput satellites. The thesis focuses mainly on systems that are able to be integrated on-chip. Some of the most novel structures of integrated semiconductor lasers of the last decade will be presented, aiming the frequency generation in the Ka(25 GHz), Q(32 GHz) and V(50 GHz) bands. These laser structures have tunability as a key point. They can cover the entire microwave and millimeter range, while keeping low size, weight and reduced power consumption. This is a major advantage over conventional radio frequency systems. The main drawback is the stability of the generated signal. The thesis proposes a study of three generation techniques based on single-mode lasers, pulsed lasers
and extended cavity lasers. Single-mode lasers have been approached from the point of view of using different integration platforms, such as monolithic indium phosphide and hybrid polymer indium phosphide. As figures of merit, using semiconductor lasers fabricated on monolithic indium phosphide a signal stability generated at 21 GHz of 300 MHz in 5 minutes of measurement has been reported. Using semiconductor lasers on the polymer indium phosphide hybrid platform with a generated signal stability at 23 GHz of 120 MHz in 5 minutes of measurement. The use of pulsed lasers has been proposed to increase the stability of the generated signal. A laser structure known as mode-locked laser has been used. This device has reported stability at 33 GHz generated signal of 2 MHz in 5 minutes of measurement.
And finally, using extended cavity integrated lasers fabricated on a hybrid platform of indium phosphide with silicon nitride, the stability of the signal generated at 25 GHz of less than 30 MHz in 10 minutes of measurement has been reported, being the most suitable of the three studied. In this thesis, the generation technique based on external modulation as an alternative to
frequency generation purely based on lasers is also studied. It has been analyzed from the integrated point of view where signal generation from DC to 16 GHz has been demonstrated on a chip fabricated on the indium phosphide integrated platform. In order to compensate the frequency limitations of the integration platform, the implementation using discrete components has been proposed where signal generation from DC to 100 GHz has been demonstrated using this technique. Finally, the THORMUX project is presented. This project is funded by the European Space Agency (ESA) and was conceived due to a great part of the results obtained during
the development of this thesis. The main objective is the implementation of a photonic multiplexer/demultiplexer capable of working in Ka, Q and V bands. Some of the preliminary results obtained during the first stages of the project and the future lines will be presented.Programa de Doctorado en Ingeniería Aeroespacial por la Universidad Carlos III de MadridPresidente: Rui Lemos Alvares Dos Santos.- Secretario: David Ricardo Sánchez Montero.- Vocal: Enrico Li
La Estrategia Digital de la Unión Europea. ¿Quo vadis sector telco? Propuesta de un nuevo marco jurídico para el sector en la UE
No full textPrograma de Doctorado en Derecho por la Universidad Carlos III de MadridPresidenta: Ana María Manero Salvador.- Secretario: Rafael Caballero Sánchez.- Vocal: Edurne Navarro Varon
The distribution of food in local food systems: the coexistence of proximity and digitalization
No full textLa distribución de alimentos a través de canales cortos o de proximidad o como Europa puntualiza: cadenas cortas de distribución de alimentos, podría estar transformando, a través del Pacto Verde y la Economía Circular, los tradicionales mercados municipales de abastos. Se observa en el estudio que esa concepción del acercamiento de la alimentación al ciudadano es tradicional en muchos países y en España también, sin embargo, algunas notas de ese nuevo sistema, como la digitalización de la distribución alimentaria en plataformas digitales o marketplaces, incorpora novedades o enfoques disímiles a los clásicos de los mercados locales. De este modo, la concepción del empoderamiento del consumidor más informado y consciente de la sostenibilidad de su consumo en una Europa con economía circular reivindica una mayor armonización y vertebración de un sistema legal fragmentado.The short food suply chanels could be shaping through the Green Deal and Circular Economy the traditional municipal food markets. The study tries to describe how bringing food closer to the citizen is a traditional idea in many countries and in Spain also, however, some aspects of this new system, such as the digitalisation of food distribution on digital platforms or marketplaces, incorporate new features or approaches that are different from the classic local markets. Thus, the concept of empowering consumers who are more informed and aware of the sustainability of their consumption in a Europe with a circular economy calls for greater harmonisation and structuring of a fragmented legal system.La distribució d'aliments a través de canals curts o de proximitat o com Europa puntualitza: cadenes curtes de distribució d'aliments podria transformar, a través del Pacte Verd i l'Economia Circular, els tradicionals mercats municipals d'abastaments. A l'estudi s'observa que aquesta concepció de l'acostament de l'alimentació al ciutadà és tradicional a molts països ia Espanya també, però, algunes notes d'aquest nou sistema, com ara la digitalització de la distribució alimentària en plataformes digitals o marketplaces, incorpora novetats o enfocaments dissímils als clàssics dels mercats locals. D'aquesta manera, la concepció de l'apoderament del consumidor més informat i conscient de la sostenibilitat del seu consum en una Europa amb economia circular reivindica més harmonització i vertebració d'un sistema legal fragmentat
Multispectral imaging for characterizing autofluorescent tissues
No full textSelective Plane Illumination Microscopy (SPIM) has become an emerging technology since its first application for 3D in-vivo imaging of the development of a living organism. An extensive number of works have been published, improving both the speed of acquisition and the resolution of the systems. Furthermore, multispectral imaging allows the effective separation of overlapping signals associated with different fluorophores from the spectrum over the whole field-of-view of the analyzed sample. To eliminate the need of using fluorescent dyes, this technique can also be applied to autofluorescence imaging. However, the effective separation of the overlapped spectra in autofluorescence imaging necessitates the use of mathematical tools. In this work, we explore the application of a method based on Principal Component Analysis (PCA) that enables tissue characterization upon spectral autofluorescence data without the use of fluorophores. Thus, enabling the separation of different tissue types in fixed and living samples with no need of staining techniques. Two procedures are described for acquiring spectral data, including a single excitation based method and a multi-excitation scanning approach. In both cases, we demonstrate the effective separation of various tissue types based on their unique autofluorescence spectra.RF acknowledges funding from Ministerio de Ciencia e Innovacion of Spain (project PID2021-123124OB-I00). JR acknowledges funding from the Ministerio de Ciencia e Innovacion (PID2020-115088RB-I00, "BEHAVE-3D"). MD and MVG-G acknowledge funding from Instituto de Salud Carlos III through the project DTS22 /00030. This project was co-funded by the European Union (ERDF, "A way to make Europe"), partially supported by Comunidad de Madrid (S2017/BMD-3867 RENIM-CM), and co-financed by European Structural and Investment Fund. The CNIC is supported by Instituto de Salud Carlos III (ISCIII), Ministerio de Ciencia e Innovacion (MCIN) and the Pro CNIC Foundation, and is a Severo Ochoa Center of Excellence (SEV-2015-0505)