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Sharing a single, large touchscreen between several collaborating users is the research area of multi-user touchscreen interfaces, also named collaborative groupware. Collaborative groupware concerns how to best facilitate teamwork over such shared digital spaces. The technology is used in a number of high-technological and expert-dominated domains including emergency coordination, urban planning, military strategy, etc. This thesis investigates the problem of how to facilitate such mixed-focus work on a multi-user touchscreen in a two-dimensional geospatial context - a digital map - while avoiding the problematic use of widgets and click interfaces. Through a background study of previous work, a new solution is suggested. It is a handchord-input-based interface that uses hand-pattern recognition to interface with multiple users simultaneously and provides graphical tools to enable and enhance geospatial collaborative work. This solution is implemented and evaluated in two user studies. The first investigates the solution in the aspects of practical interfacing, tool impact, and hybrid collaboration on small teams of two. A second smaller expert user study evaluates the technique in the aspects of responsiveness, effectiveness, and representation; with more formalized procedures. The results show that a strong majority of users in the first study could successfully and quickly learn chord-input interfacing, and use it to access a variety of functionality with effectivity and enhancement of collaboration. The results of the second survey received moderately positive feedback in all aspects, with reserved opinions for its usage potential. These results indicate that chord-based interfacing, successfully implemented, could contribute to improved teamwork and task-solving in relevant collaborative contexts., Kollaborativa gruppprogramet är området som faciliterar samarbete på delade digitala utrymmen. Den här tesen utreder problemet om hur man faciliterar kollaborativ, mix-fokuserad arbete på en fleranvändarpekskärm i en geospatial konext utan att använda problematiska knappar och klickbara gränssnitt. Kollaborativa geospatiala gränsnittanvänds i ett flertal av högteknologiska expertdominerade domäner som inkluderar nödsituationskoordinering, , militär strategi, etc. Den föreslagna lösningen är ett handackordsbaserat gränsnitt som använder fingeringenkänning för att interagera flera användare samtidigt och förse verktyg som möjliggör och förbättrar geospatialt samarbete. Denna lösning implementeras och är möjligtvis den mest omfattande implementationen av hand-ackord, men med signifikanta buggar. Denna utvärderas i två användarstudier. Den första undersöker lösningen i aspekterna av handackordsinteraktion, verktygens påverkan och hybridsamarbete i små lag om två. En andra, mindre studie utvärderar tekniken i termer av gensvar, effektivet och representation. Resultatet visar att ackord-baserade gränssnitt kan framgångsrikt förse en mångfald av funktionalitet med effektivtet och förbättring av samarbete i en geospatial kontext. Resultatet av den första studien visar att handackordbaserade kan bidra till förbättrat samarbete och problemlösning i geospatiala kontexter på en fleranvändarpekskärm, där vissa användare finner det mer praktiskt och enklare att bemästra än andra. Resultatet av den andra studien påvisade tämligen positiv respons i alla aspekter, med reservation för dess tillämpningspotential.

Sharing a single, large touchscreen between several collaborating users is the research area of multi-user touchscreen interfaces, also named collaborative groupware. Collaborative groupware concerns how to best facilitate teamwork over such shared digital spaces. The technology is used in a number of high-technological and expert-dominated domains including emergency coordination, urban planning, military strategy, etc. This thesis investigates the problem of how to facilitate such mixed-focus work on a multi-user touchscreen in a two-dimensional geospatial context - a digital map - while avoiding the problematic use of widgets and click interfaces. Through a background study of previous work, a new solution is suggested. It is a handchord-input-based interface that uses hand-pattern recognition to interface with multiple users simultaneously and provides graphical tools to enable and enhance geospatial collaborative work. This solution is implemented and evaluated in two user studies. The first investigates the solution in the aspects of practical interfacing, tool impact, and hybrid collaboration on small teams of two. A second smaller expert user study evaluates the technique in the aspects of responsiveness, effectiveness, and representation; with more formalized procedures. The results show that a strong majority of users in the first study could successfully and quickly learn chord-input interfacing, and use it to access a variety of functionality with effectivity and enhancement of collaboration. The results of the second survey received moderately positive feedback in all aspects, with reserved opinions for its usage potential. These results indicate that chord-based interfacing, successfully implemented, could contribute to improved teamwork and task-solving in relevant collaborative contexts., Kollaborativa gruppprogramet är området som faciliterar samarbete på delade digitala utrymmen. Den här tesen utreder problemet om hur man faciliterar kollaborativ, mix-fokuserad arbete på en fleranvändarpekskärm i en geospatial konext utan att använda problematiska knappar och klickbara gränssnitt. Kollaborativa geospatiala gränsnittanvänds i ett flertal av högteknologiska expertdominerade domäner som inkluderar nödsituationskoordinering, , militär strategi, etc. Den föreslagna lösningen är ett handackordsbaserat gränsnitt som använder fingeringenkänning för att interagera flera användare samtidigt och förse verktyg som möjliggör och förbättrar geospatialt samarbete. Denna lösning implementeras och är möjligtvis den mest omfattande implementationen av hand-ackord, men med signifikanta buggar. Denna utvärderas i två användarstudier. Den första undersöker lösningen i aspekterna av handackordsinteraktion, verktygens påverkan och hybridsamarbete i små lag om två. En andra, mindre studie utvärderar tekniken i termer av gensvar, effektivet och representation. Resultatet visar att ackord-baserade gränssnitt kan framgångsrikt förse en mångfald av funktionalitet med effektivtet och förbättring av samarbete i en geospatial kontext. Resultatet av den första studien visar att handackordbaserade kan bidra till förbättrat samarbete och problemlösning i geospatiala kontexter på en fleranvändarpekskärm, där vissa användare finner det mer praktiskt och enklare att bemästra än andra. Resultatet av den andra studien påvisade tämligen positiv respons i alla aspekter, med reservation för dess tillämpningspotential.

Different from conventional reconfigurable intelligent surfaces (RIS), simultaneous transmitting and reflecting RIS (STAR-RIS) can reflect and transmit signals to the receiver. In this paper, to serve more ground users and increase deployment flexibility, we investigate an unmanned aerial vehicle (UAV) equipped with STAR-RIS (STAR-RIS-UAV)-aided wireless communications for multi-user networks. Energy splitting (ES) and mode switching (MS) protocols are considered to control the reflection and transmission coefficients of STAR-RIS elements. To maximize the sum rate of the STAR-RIS-UAV-aided coordinated multipoint (CoMP) cellular system for multi-user networks, the corresponding beamforming vectors as well as transmitted and reflected coefficient matrices are optimized. Specifically, instead of adopting the alternating optimization, we design an iteration method to optimize all variables for both the ES and MS protocols at the same time. Simulation results reveal that the STAR-RIS-UAV-aided CoMP system has a much higher sum rate than systems with conventional RIS or without RIS. Furthermore, the proposed structure is more flexible than fixed STAR-RIS and could greatly promote the sum rate.

This chapter works on crafting a generally enhanced transceiver explicitly for wideband multi-user (wMU) mmWave massive multiple-input multiple-output (mMIMO), aiming to maximize mutual information (MI). The proposed scheme follows the prevalent hybrid block diagonalization (HBD-)based framework and further proves that HBD is optimal in the sense of MI. Specifically, the transceiver design decouples hybrid processing into two-stage analog and digital processing, with which one can derive the MI bounds associated with HBD. After demonstrating the bound tightness, we obtain the excellent HBD transceivers by optimizing the lower bound. The proposed HBD technique does not rely on substantial computational complexity, striking channel sparsity, or high-resolution analog beamformers and can achieve a superb MI performance even with inferior hardware configurations. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.

This paper proposes an inverse reinforcement learning (IRL)-based method to optimize power allocation for multiuser cellular networks. An optimization problem is formulated to maximize the achievable sum information rate of all receivers. In contrast to traditional reinforcement learning (RL)-based methods, the proposed IRL-based one does not require to design the reward function manually, which is able to determine the reward function efficiently and automatically from the expert policy. The weighted minimum mean square error (WMMSE) method is used to serve as an expert policy to obtain the reward function, and the action space and state space are designed. Simulation results show that the proposed IRL-based method achieves about 99 % of the sum information rate achieved by the pure WMMSE method, but the running time of the proposed IRL-based one is about 1/19 of that required of pure WMMSE method. © 2022 IEEE.

LoRaWAN is a popular wireless technology that provides long-range connectivity to Internet-of-Things devices using a bit-interleaved coded modulation. To minimize their energy consumption, LoRaWAN end-nodes implement a pure ALOHA access scheme, which leads to collisions among users at the gateway and a reduced throughput in crowded networks. To improve the throughput of interference-limited LoRaWAN networks, we design in this paper a successive interference cancellation receiver that is able to decode frames from two colliding users. By performing both a soft-demodulation and soft-decoding to recover the message of each interfering user, the proposed two-user receiver explicitly leverages the coded spread spectrum modulation of LoRa. We show that the joint usage of interleaving and coding is critical to achieve a decent cancellation of the strongest user. Simulation results indicate that our two-user receiver successfully demodulates the frames of two interfering users with a 1.5 dB difference of received powers, even at very low signal-to-noise ratios.

Due to technological enhancements, such as mobile TV, streaming services, smart grids and augmented reality, the need to optimize the overall network throughput becomes one of the most important aspects of communication systems. In this thesis, we analyze the resource allocation problem of four different wireless communication systems with the objective of maximizing the achievable sum-rate. From a theoretical perspective, the achievable sum-rate optimization problem is very hard to solve. As such, the challenge is to solve these non-convex and NP-hard optimization problems with an acceptable level of complexity. We first consider two full-duplex and half-duplex networks and investigate the optimality of binary power allocation. In terms of the transmit power allocation, the simple power allocation method known as the binary power allocation is known to be optimal for special wireless network structures. Therefore, we derive new, necessary and sufficient conditions that would ensure the optimality of binary power allocation for such networks. We further extend our analysis to investigate the sub-optimality associated with binary power allocation and show that the loss of achievable sum-rate due to binary power allocation is negligible. Next, we concentrate on the transmission direction control in flexible duplex networks such that the achievable sum-rate is maximized. We analyze several existing approximation techniques and their feasibility for solving the resulting NP-hard optimization problem. We also develop a novel low-cost heuristic pattern search algorithm based on the direct search of function value. For a flexible network where each node has one potential desired link, we observe that the proposed algorithm has better achievable sum-rate compared to the approximation techniques and other existing resource allocation approaches. In reality, however, a node can have more than one potential desired link. As such, transmitter and receiver scheduling becomes imp

[ES] La diabetes mellitus tipo 1 es una enfermedad que necesita un amplio conocimiento y dedicación para su adecuada gestión. Este problema se acrecienta en edades tempranas, donde la asimilación de conceptos y rutinas requiere del uso de métodos más didácticos y enfocados al rango de edad. En el presente proyecto se desarrolla una herramienta multiplataforma, enfocada en la educación diabetológica, con la que poder transmitir de una forma más empática los conceptos básicos que un niño que se inicia en la enfermedad debe conocer. La herramienta implementada constará de una aplicación desarrollada en Unity donde se integrarán, en un concepto multiusuario, juegos de competición y aprendizaje mutuo. Todo esto será complementado mediante la adición de dispositivos robóticos, basados en Arduino, que dotarán a la herramienta de una interfaz mucho más amigable y cercana hacia los usuarios finales., [CA] La diabetis mellitus tipus 1 és una malaltia que necessita d'un ampli coneixement i dedicació per una adequada gestió. Aquest problema s'incrementa a tempranes edats, on l'assimilació de conceptes i rutines requereix de l'ús de mètodes més didàctics i enfocats a la franja d'edat. En el present projecte es desenvolupa una eina multiplataforma, enfocada en l'educació diabetològica, amb la qual poder transmetre d'una forma més empàtica els conceptes bàsics que un xiquet que s'inicia en la malaltia ha de conèixer. L'eina implementada constarà d'una aplicación desenvolupada en Unity on s'integren, en un concepte multiusuari, jocs de competició i aprenentatge mutu. Tot això serà complementada mitjançant l'addició de dispositius robòtics, basats en Arduino, que dota l'eina d'una interfície molt més amigable i propera cap als usuaris finals., [EN] Type 1 diabetes mellitus is a disease that requires extensive knowledge and dedication for its proper management. This problem increases in early ages, where the assimilation of concepts and routines requires the use of more didactic methods focused on the age range. In the present project, a multiplatform tool is developed, focused on diabetes education, with which to transmit in a more empathetic way the basic concepts that a child who is beginning to suffer from the disease must know. The tool implemented will consist of an application developed at Unity where competitive games and mutual learning will be integrated into a multi-user concept. All this will be complemented by the addition of robotic devices, based on Arduino, which will provide the tool with a much more friendly interface and closer to the end users.

[ES] La diabetes mellitus tipo 1 es una enfermedad que necesita un amplio conocimiento y dedicación para su adecuada gestión. Este problema se acrecienta en edades tempranas, donde la asimilación de conceptos y rutinas requiere del uso de métodos más didácticos y enfocados al rango de edad. En el presente proyecto se desarrolla una herramienta multiplataforma, enfocada en la educación diabetológica, con la que poder transmitir de una forma más empática los conceptos básicos que un niño que se inicia en la enfermedad debe conocer. La herramienta implementada constará de una aplicación desarrollada en Unity donde se integrarán, en un concepto multiusuario, juegos de competición y aprendizaje mutuo. Todo esto será complementado mediante la adición de dispositivos robóticos, basados en Arduino, que dotarán a la herramienta de una interfaz mucho más amigable y cercana hacia los usuarios finales., [CA] La diabetis mellitus tipus 1 és una malaltia que necessita d'un ampli coneixement i dedicació per una adequada gestió. Aquest problema s'incrementa a tempranes edats, on l'assimilació de conceptes i rutines requereix de l'ús de mètodes més didàctics i enfocats a la franja d'edat. En el present projecte es desenvolupa una eina multiplataforma, enfocada en l'educació diabetològica, amb la qual poder transmetre d'una forma més empàtica els conceptes bàsics que un xiquet que s'inicia en la malaltia ha de conèixer. L'eina implementada constarà d'una aplicación desenvolupada en Unity on s'integren, en un concepte multiusuari, jocs de competició i aprenentatge mutu. Tot això serà complementada mitjançant l'addició de dispositius robòtics, basats en Arduino, que dota l'eina d'una interfície molt més amigable i propera cap als usuaris finals., [EN] Type 1 diabetes mellitus is a disease that requires extensive knowledge and dedication for its proper management. This problem increases in early ages, where the assimilation of concepts and routines requires the use of more didactic methods focused on the age range. In the present project, a multiplatform tool is developed, focused on diabetes education, with which to transmit in a more empathetic way the basic concepts that a child who is beginning to suffer from the disease must know. The tool implemented will consist of an application developed at Unity where competitive games and mutual learning will be integrated into a multi-user concept. All this will be complemented by the addition of robotic devices, based on Arduino, which will provide the tool with a much more friendly interface and closer to the end users.

[ES] La diabetes mellitus tipo 1 es una enfermedad que necesita un amplio conocimiento y dedicación para su adecuada gestión. Este problema se acrecienta en edades tempranas, donde la asimilación de conceptos y rutinas requiere del uso de métodos más didácticos y enfocados al rango de edad. En el presente proyecto se desarrolla una herramienta multiplataforma, enfocada en la educación diabetológica, con la que poder transmitir de una forma más empática los conceptos básicos que un niño que se inicia en la enfermedad debe conocer. La herramienta implementada constará de una aplicación desarrollada en Unity donde se integrarán, en un concepto multiusuario, juegos de competición y aprendizaje mutuo. Todo esto será complementado mediante la adición de dispositivos robóticos, basados en Arduino, que dotarán a la herramienta de una interfaz mucho más amigable y cercana hacia los usuarios finales., [CA] La diabetis mellitus tipus 1 és una malaltia que necessita d'un ampli coneixement i dedicació per una adequada gestió. Aquest problema s'incrementa a tempranes edats, on l'assimilació de conceptes i rutines requereix de l'ús de mètodes més didàctics i enfocats a la franja d'edat. En el present projecte es desenvolupa una eina multiplataforma, enfocada en l'educació diabetològica, amb la qual poder transmetre d'una forma més empàtica els conceptes bàsics que un xiquet que s'inicia en la malaltia ha de conèixer. L'eina implementada constarà d'una aplicación desenvolupada en Unity on s'integren, en un concepte multiusuari, jocs de competició i aprenentatge mutu. Tot això serà complementada mitjançant l'addició de dispositius robòtics, basats en Arduino, que dota l'eina d'una interfície molt més amigable i propera cap als usuaris finals., [EN] Type 1 diabetes mellitus is a disease that requires extensive knowledge and dedication for its proper management. This problem increases in early ages, where the assimilation of concepts and routines requires the use of more didactic methods focused on the age range. In the present project, a multiplatform tool is developed, focused on diabetes education, with which to transmit in a more empathetic way the basic concepts that a child who is beginning to suffer from the disease must know. The tool implemented will consist of an application developed at Unity where competitive games and mutual learning will be integrated into a multi-user concept. All this will be complemented by the addition of robotic devices, based on Arduino, which will provide the tool with a much more friendly interface and closer to the end users.

[ES] La diabetes mellitus tipo 1 es una enfermedad que necesita un amplio conocimiento y dedicación para su adecuada gestión. Este problema se acrecienta en edades tempranas, donde la asimilación de conceptos y rutinas requiere del uso de métodos más didácticos y enfocados al rango de edad. En el presente proyecto se desarrolla una herramienta multiplataforma, enfocada en la educación diabetológica, con la que poder transmitir de una forma más empática los conceptos básicos que un niño que se inicia en la enfermedad debe conocer. La herramienta implementada constará de una aplicación desarrollada en Unity donde se integrarán, en un concepto multiusuario, juegos de competición y aprendizaje mutuo. Todo esto será complementado mediante la adición de dispositivos robóticos, basados en Arduino, que dotarán a la herramienta de una interfaz mucho más amigable y cercana hacia los usuarios finales., [CA] La diabetis mellitus tipus 1 és una malaltia que necessita d'un ampli coneixement i dedicació per una adequada gestió. Aquest problema s'incrementa a tempranes edats, on l'assimilació de conceptes i rutines requereix de l'ús de mètodes més didàctics i enfocats a la franja d'edat. En el present projecte es desenvolupa una eina multiplataforma, enfocada en l'educació diabetològica, amb la qual poder transmetre d'una forma més empàtica els conceptes bàsics que un xiquet que s'inicia en la malaltia ha de conèixer. L'eina implementada constarà d'una aplicación desenvolupada en Unity on s'integren, en un concepte multiusuari, jocs de competició i aprenentatge mutu. Tot això serà complementada mitjançant l'addició de dispositius robòtics, basats en Arduino, que dota l'eina d'una interfície molt més amigable i propera cap als usuaris finals., [EN] Type 1 diabetes mellitus is a disease that requires extensive knowledge and dedication for its proper management. This problem increases in early ages, where the assimilation of concepts and routines requires the use of more didactic methods focused on the age range. In the present project, a multiplatform tool is developed, focused on diabetes education, with which to transmit in a more empathetic way the basic concepts that a child who is beginning to suffer from the disease must know. The tool implemented will consist of an application developed at Unity where competitive games and mutual learning will be integrated into a multi-user concept. All this will be complemented by the addition of robotic devices, based on Arduino, which will provide the tool with a much more friendly interface and closer to the end users.

The emerging field of Virtual Reality (VR) and Augmented Reality (AR) systems and solutions lead to new opportunities for learning and education. In this review we investigate how and why VR/AR tools and applications contribute to the learning of new knowledge and skills, using a core set of literature reviews, and we also look at the research and development of VR/AR within the Utrecht University. We draw some conclusions and propose recommendations. The report is the result of a cooperation between teachers and researchers of the Utrecht University. Virtual Reality and Augmented Reality in Education Universiteit Utrecht 4 Content

[ES] El objeto del presente trabajo de fin de grado consiste en diseñar una instalación transportable de lavamanos y bidón de agua recargable para espacios públicos, desde la definición de la problemática a resolver con sus limitaciones y condiciones, la búsqueda de referencias y productos existentes, pasando por el desarrollo de diferentes propuestas hasta escoger la más adecuada, junto a su explicación y justificación en detalle., [EN] The purpose of this final degree project is to design a transportable installation of sinks and rechargeable water can for public spaces, from the definition of the problem to be solved with its limitations and conditions, the search for references and existing products, passing through the development of different proposals until choosing the most appropriate one, with its explanation and justification in detail.

[ES] El objeto del presente trabajo de fin de grado consiste en diseñar una instalación transportable de lavamanos y bidón de agua recargable para espacios públicos, desde la definición de la problemática a resolver con sus limitaciones y condiciones, la búsqueda de referencias y productos existentes, pasando por el desarrollo de diferentes propuestas hasta escoger la más adecuada, junto a su explicación y justificación en detalle., [EN] The purpose of this final degree project is to design a transportable installation of sinks and rechargeable water can for public spaces, from the definition of the problem to be solved with its limitations and conditions, the search for references and existing products, passing through the development of different proposals until choosing the most appropriate one, with its explanation and justification in detail.

[ES] El objeto del presente trabajo de fin de grado consiste en diseñar una instalación transportable de lavamanos y bidón de agua recargable para espacios públicos, desde la definición de la problemática a resolver con sus limitaciones y condiciones, la búsqueda de referencias y productos existentes, pasando por el desarrollo de diferentes propuestas hasta escoger la más adecuada, junto a su explicación y justificación en detalle., [EN] The purpose of this final degree project is to design a transportable installation of sinks and rechargeable water can for public spaces, from the definition of the problem to be solved with its limitations and conditions, the search for references and existing products, passing through the development of different proposals until choosing the most appropriate one, with its explanation and justification in detail.

[ES] El objeto del presente trabajo de fin de grado consiste en diseñar una instalación transportable de lavamanos y bidón de agua recargable para espacios públicos, desde la definición de la problemática a resolver con sus limitaciones y condiciones, la búsqueda de referencias y productos existentes, pasando por el desarrollo de diferentes propuestas hasta escoger la más adecuada, junto a su explicación y justificación en detalle., [EN] The purpose of this final degree project is to design a transportable installation of sinks and rechargeable water can for public spaces, from the definition of the problem to be solved with its limitations and conditions, the search for references and existing products, passing through the development of different proposals until choosing the most appropriate one, with its explanation and justification in detail.

Virtual Reality provides the ability to immerse users in realistic environments, which makes it possible to utilize the technology as an educational tool. The EIT Raw Materials Project MireBooks intend to teach mining students by simulating a VR mine and recreating learning experiences in it. With this comes challenges with regards to the networking performance and user experience., MiReBooks

Virtual Reality provides the ability to immerse users in realistic environments, which makes it possible to utilize the technology as an educational tool. The EIT Raw Materials Project MireBooks intend to teach mining students by simulating a VR mine and recreating learning experiences in it. With this comes challenges with regards to the networking performance and user experience., MiReBooks

In this paper, we design linear precoders for the downlink of a visible light communication (VLC) system that simultaneously serves multiple users. Instead of using phosphor-coated white light-emitting diodes (PWLEDs), we focus on Red-Green-Blue light-emitting diodes (RGB-LEDs) that allow modulating three separate data streams on the three primary colors of the RGB-LEDs. For this system, we design a zero-forcing (ZF) precoder that maximizes the weighted sum rate for a multilevel pulse amplitude modulation (M-PAM). The precoding design in RGB-based systems presents some challenges due to the system constraints, such as the limited power, the non-negative amplitude constraints per light-emitting diode (LED), and the need to guarantee white light emission while transmitting with RGB-LEDs. For comparison purposes, we also consider the ZF design for a PWLED-based system and evaluate the performance of both a PWLED- and an RGB-based system., The work has been supported by the Secretaria d’Universitats i Recerca Departament d’Empresa i Coneixement (AGAUR) of the Generalitat de Catalunya SGR grant 2017-SGR-578 and has been funded by the Agencia Estatal de Investigacion (AEI)/Fondo Europeo de Desarrollo Regional (FEDER) through the project TEC2016-77148-C2-1-R (AEI/FEDER, UE)., Peer Reviewed, Postprint (published version)

We aim to design an analog-only beamforming scheme for downlink multi-user mm-wave systems to optimize the beamforming gain and the inter-user interference at the same time. Traditional analog beamforming schemes, such as the beam selection method, use the array response vector corresponding to the strongest path of the channel to generate a beam pointing to the user. In multi-user systems, such schemes will lead to large inter-user interference, especially when the users are closely located. In this paper, we formulate a multi-objective problem to strike a balance between the beamforming gain and the inter-user interference. To solve the problem, we first use the weighted-sum method to transform the multi-objective problem into a single-objective problem. Then, we use the semi-definite programing technique to make the analog beamforming with constant-magnitude constraints tractable. Furthermore, to alleviate the effects of the channel estimation and feedback quantization errors, we design a robust beamforming scheme to provide robustness against imperfect channel information. We first develop a channel error model for the scattering clustered channel model, which can serve as a general channel error model for the mm-wave channels. Then, we formulate a multi-objective problem using the stochastic approach to suppress the interference and enhance the beamforming gain at the same time. The simulation results show that our proposed non-robust multi-user analog beamformer outperforms the traditional analog beamforming method when the SNR is high and our proposed robust beamformer can provide up to 109% improvement in the sum-rate compared with the beam selection method.

[EN] The presented work consists of the realization of the exterior and interior conceptual design of an autonomous vehicle positioned in the segment of high-end passenger cars as a transport solution of the future for an urban mobility company. The structure of this project is divided into 5 parts, an introductory section where the current problems that could solve this conceptual proposal are detailed as well as the objectives of the project, and a summary about the autonomous vehicle that formalize the background of this project. The second part consists of a market study where diverse characteristics to be studied of the competition and influential markets are analyzed, as well as the brand study to be chosen. The third part consists of the formalization of the design requirements as well as the realization of multiple aesthetic proposals in the form of sketches until concluding with a final design. The fourth is about three-dimensional modeling of that proposal using various computer-aided design programs. Finally we have the business proposal where it is explained how the service that makes use of the vehicle to be designed works, as well as the visualization of it through the use of renders. The main objective is to present an alternative urban mobility that is similar in efficiency to public transport but with the advantages of privacy, freedom of mobility and qualities of high-end private vehicles., [ES] El trabajo presentado consta de la realización del diseño conceptual exterior e interior de un vehículo autónomo posicionado en el segmento de gama alta de turismos como solución de transporte del futuro para una empresa de movilidad urbana. La estructura de este proyecto se divide en 5 partes, una introductoria donde se comenta los problemas actuales que podría resolver esta propuesta conceptual así como los objetivos del proyecto, y un resumen sobre el vehículo autónomo que formalizan la base de antecedentes de este proyecto. La segunda parte consta de un estudio de mercado donde se analizan diversas características a estudiar de la competencia y mercados influyentes, así como del estudio de marca a escoger. La tercera parte consta de la formalización de los requisitos de diseño así como de la realización de múltiples propuestas estéticas en forma de bocetos hasta concluir con el diseño final. Por cuarto tenemos el modelado tridimensional de esa propuesta usando diversos programas de diseño asistido por ordenador. Finalmente tenemos la propuesta de negocio donde se explica como funciona el servicio que hace uso del vehículo a diseñar, así como la visualización de este mediante el uso de renderizados. El objetivo principal es presentar una alternativa de movilidad urbana que se asemeje en eficiencia al transporte público pero con las ventajas de privacidad, libertad de movilidad y calidades de vehículos privados de alta gama. tenemos la propuesta de negocio donde se explica como funciona el servicio que hace uso del vehículo a diseñar, así como la visualización de este mediante el uso de renderizados. El objetivo principal es presentar una alternativa de movilidad urbana que se asemeje en eficiencia al transporte público pero con las ventajas de privacidad, libertad de movilidad y calidades de vehículos privados de alta gama.

[EN] The presented work consists of the realization of the exterior and interior conceptual design of an autonomous vehicle positioned in the segment of high-end passenger cars as a transport solution of the future for an urban mobility company. The structure of this project is divided into 5 parts, an introductory section where the current problems that could solve this conceptual proposal are detailed as well as the objectives of the project, and a summary about the autonomous vehicle that formalize the background of this project. The second part consists of a market study where diverse characteristics to be studied of the competition and influential markets are analyzed, as well as the brand study to be chosen. The third part consists of the formalization of the design requirements as well as the realization of multiple aesthetic proposals in the form of sketches until concluding with a final design. The fourth is about three-dimensional modeling of that proposal using various computer-aided design programs. Finally we have the business proposal where it is explained how the service that makes use of the vehicle to be designed works, as well as the visualization of it through the use of renders. The main objective is to present an alternative urban mobility that is similar in efficiency to public transport but with the advantages of privacy, freedom of mobility and qualities of high-end private vehicles., [ES] El trabajo presentado consta de la realización del diseño conceptual exterior e interior de un vehículo autónomo posicionado en el segmento de gama alta de turismos como solución de transporte del futuro para una empresa de movilidad urbana. La estructura de este proyecto se divide en 5 partes, una introductoria donde se comenta los problemas actuales que podría resolver esta propuesta conceptual así como los objetivos del proyecto, y un resumen sobre el vehículo autónomo que formalizan la base de antecedentes de este proyecto. La segunda parte consta de un estudio de mercado donde se analizan diversas características a estudiar de la competencia y mercados influyentes, así como del estudio de marca a escoger. La tercera parte consta de la formalización de los requisitos de diseño así como de la realización de múltiples propuestas estéticas en forma de bocetos hasta concluir con el diseño final. Por cuarto tenemos el modelado tridimensional de esa propuesta usando diversos programas de diseño asistido por ordenador. Finalmente tenemos la propuesta de negocio donde se explica como funciona el servicio que hace uso del vehículo a diseñar, así como la visualización de este mediante el uso de renderizados. El objetivo principal es presentar una alternativa de movilidad urbana que se asemeje en eficiencia al transporte público pero con las ventajas de privacidad, libertad de movilidad y calidades de vehículos privados de alta gama. tenemos la propuesta de negocio donde se explica como funciona el servicio que hace uso del vehículo a diseñar, así como la visualización de este mediante el uso de renderizados. El objetivo principal es presentar una alternativa de movilidad urbana que se asemeje en eficiencia al transporte público pero con las ventajas de privacidad, libertad de movilidad y calidades de vehículos privados de alta gama.

We aim to design an analog-only beamforming scheme for downlink multi-user mm-wave systems to optimize the beamforming gain and the inter-user interference at the same time. Traditional analog beamforming schemes, such as the beam selection method, use the array response vector corresponding to the strongest path of the channel to generate a beam pointing to the user. In multi-user systems, such schemes will lead to large inter-user interference, especially when the users are closely located. In this paper, we formulate a multi-objective problem to strike a balance between the beamforming gain and the inter-user interference. To solve the problem, we first use the weighted-sum method to transform the multi-objective problem into a single-objective problem. Then, we use the semi-definite programing technique to make the analog beamforming with constant-magnitude constraints tractable. Furthermore, to alleviate the effects of the channel estimation and feedback quantization errors, we design a robust beamforming scheme to provide robustness against imperfect channel information. We first develop a channel error model for the scattering clustered channel model, which can serve as a general channel error model for the mm-wave channels. Then, we formulate a multi-objective problem using the stochastic approach to suppress the interference and enhance the beamforming gain at the same time. The simulation results show that our proposed non-robust multi-user analog beamformer outperforms the traditional analog beamforming method when the SNR is high and our proposed robust beamformer can provide up to 109% improvement in the sum-rate compared with the beam selection method.

In this paper, a new mode selection (MS) scheme for device-to-device (D2D) enabled cellular networks is proposed. The MS is carried out using a predefined signal-to-interference plus noise ratio threshold and it aims to guarantee a minimum level of quality of service.With the new scheme, interfering effects are taken into consideration, while realistic assumptions for the acquisition of the channel information are made. Assuming a single-user case, an analytical framework is developed, which is based on the Markov-chain theory, and is used to study the system's performance. The various performance results that have been obtained reveal that with the proposed MS, the probability of mode switching can be reduced (as compared to other systems) and thus, an increase on the overhead and signal processing is avoided. Moreover, the new approach is applied in a multi-user communication scenario, where a joint MS, resource allocation (RA), and scheduling optimization problem is formulated. The solution to this problem is based on a greedy heuristic algorithm that properly assigns the available resources among cellular users and D2D pairs. The joint MS, RA, and scheduling algorithm considers limited SINR awareness and it provides significant performance improvement in terms of sum-rate.

There is an increasing demand for in-flight broadband connectivity. Some airlines are already deployed satellite-based solutions, which have low data rate and high latency. In order to tackle these problems, direct air-to-ground communication (DA2GC), where a direct link between a ground station and an airplane is established, is a promising solution. The resource utilization in DA2GC systems can be enhanced with the introduction of multi-user beamforming techniques, where each airplane has its dedicated beam and exploits a larger portion of the spectrum available to DA2GC. Even with multiuser beamforming technique, some airplanes may experience low data rates due to interference caused by beams aimed at airplanes in the mutual vicinity. The probability that two or more beams will interfere is higher with longer inter-site distance or wider beamwidth, which is often the case for DA2GC systems. To address significant research problem, we propose a coordinated resource allocation scheme with beam selection and spectrum allocation. The proposed beam selection scheme coordinates the neighboring base stations such that the number of airplanes sharing the same beam is minimized. In addition, the proposed coordinated spectrum allocation scheme maximizes the minimum amount of spectrum dedicated for each airplane. According to our results, the proposed coordinated beam selection with efficient spectrum allocation improves average capacity available per airplane by 60% in comparison with the uncoordinated scheme., QC 20181105

Studien avsåg att olika aspekter för att skapa underlag för utvecklingen med att förbättra fleranvändning. Syftet var, utöver de olika aspekterna, att på konceptuell nivå utvärdera hur fleranvändning kan utföras tekniskt samt undersöka hur användarna påverkas av denna förändring. Detta har utförts genom flertalet workshops och intervjuer. Vid två tillfällen har också författarna till rapporten utbildats i hur systemet är uppbyggt och hur det används. Utifrån detta har värdekriterier värderats mot olika tekniker. De teknikerna är Mutex, Semaphores och Oracle Tuxedo. På det sättet har olika aspekter beaktats och konceptuella modeller har målats upp. De olika teknikerna lever alla upp till de tekniska kraven som ställts, som programmeringsspråket C# och en databas från Oracle. I samverkan mellan användare och utvecklare har nivån på lösningen tagits fram, vad den ger användarna för nytta samtidigt som det inte är för komplicerat. Dessutom har det ställts krav angående prestandan, att den inte får försämras väsentligt. Användarna får ett liknande arbetssätt med minskade krav på samordning. Det medför att de kan samarbeta med de datamängder de behöver. Den lösning som passade bäst utifrån dessa kriterier var Mutex., This paper is intended to study different aspects and take them in consideration to create a foundation for the developers to improve a multi-user environment. The purpose was to evaluate how to develop multi-user systems at a conceptual level with the technical aspects and describe how the users were affected by this. The study is based on multiple workshops and interviews. The writers have also been educated on how the system is used by the users and how the system was built, at two separate occasions. Based on this, criterias were made and these were valued against different techniques. These techniques are Mutex, Semaphores and Oracle Tuxedo. The criterias were considered and conceptual models were made to visualize the solution. The different techniques all live up to the constraints from the hardware and software of the case study, like the programming language C# and a database from Oracle. In a cooperation between the developers and users have the level of the solution been defined, where the solution ease the problems enough and still not too complex to implement. There have also been a few directions on the performance of the system. The solution should not be affecting the performance significantly. The users’working methods are not going to be particularly affected. The main part of the cooperation are not as needed as before. They can work in the same dataset concurrent in the datasets they required. On this basis the best technique to use in this case was Mutex.

Constrained by the number of transmitted data streams, this paper proposes sub-carrier allocation (SA) and hybrid precoding (HP) designs for sum-rate maximization in mm-wave OFDMA systems. The optimization is first formulated as a computation sparsity-constrained HP design problem, which is non-convex and challenging to solve. Two two-stage solution approaches are proposed. In the first approach, a fully digital precoder (FDP) is optimized considering the computation sparsity constraint in the first stage. In the second approach, the sparsity constraint is only imposed in the second stage. To find the FDP, we employ the minimization of the weighted mean-squared error and the ℓ 1 -reweighted methods to tackle the non-convex objective function and sparsity constraints, respectively. In the second stage of each approach, we exploit an alternating weighted mean-squared error minimization algorithm to reconstruct HP's based on the FDP found in the first stage. Two novel analog precoding designs, namely semi-definite-relaxation-based and projected-gradient-descent-based, are then proposed to optimize the analog part of the obtained HP's. We also study the impacts of various system parameters on the system sum-rate and provide resource provisioning insights for HP systems. Numerical results show the superior performances of the proposed designs over joint SA and HP benchmark algorithms.

Constrained by the number of transmitted data streams, this paper proposes sub-carrier allocation (SA) and hybrid precoding (HP) designs for sum-rate maximization in mm-wave OFDMA systems. The optimization is first formulated as a computation sparsity-constrained HP design problem, which is non-convex and challenging to solve. Two two-stage solution approaches are proposed. In the first approach, a fully digital precoder (FDP) is optimized considering the computation sparsity constraint in the first stage. In the second approach, the sparsity constraint is only imposed in the second stage. To find the FDP, we employ the minimization of the weighted mean-squared error and the ℓ 1 -reweighted methods to tackle the non-convex objective function and sparsity constraints, respectively. In the second stage of each approach, we exploit an alternating weighted mean-squared error minimization algorithm to reconstruct HP's based on the FDP found in the first stage. Two novel analog precoding designs, namely semi-definite-relaxation-based and projected-gradient-descent-based, are then proposed to optimize the analog part of the obtained HP's. We also study the impacts of various system parameters on the system sum-rate and provide resource provisioning insights for HP systems. Numerical results show the superior performances of the proposed designs over joint SA and HP benchmark algorithms.

This paper presents Social MatchUP, a multiplayer Virtual Reality game for children with Neurodevelopmental Disorders (NDD). Shared virtual reality environments (SVREs) allow NDD children to interact in the same virtual space, but without the possible discomfort or fear caused by having a real person in front of them. Social MatchUP is a simple Concentration-like game, run on smartphones, where players should communicate to match up all the pairs of images they are given. Because every player can only interact with half of the pictures, but can see what his companion is doing, the game improves social and communication skills, and can be used also as a learning tool. A simple and easy-to-use customization tool was also developed to let therapists and teachers adapt the game context to the needs of the children they take care of.

Studien avsåg att olika aspekter för att skapa underlag för utvecklingen med att förbättra fleranvändning. Syftet var, utöver de olika aspekterna, att på konceptuell nivå utvärdera hur fleranvändning kan utföras tekniskt samt undersöka hur användarna påverkas av denna förändring. Detta har utförts genom flertalet workshops och intervjuer. Vid två tillfällen har också författarna till rapporten utbildats i hur systemet är uppbyggt och hur det används. Utifrån detta har värdekriterier värderats mot olika tekniker. De teknikerna är Mutex, Semaphores och Oracle Tuxedo. På det sättet har olika aspekter beaktats och konceptuella modeller har målats upp. De olika teknikerna lever alla upp till de tekniska kraven som ställts, som programmeringsspråket C# och en databas från Oracle. I samverkan mellan användare och utvecklare har nivån på lösningen tagits fram, vad den ger användarna för nytta samtidigt som det inte är för komplicerat. Dessutom har det ställts krav angående prestandan, att den inte får försämras väsentligt. Användarna får ett liknande arbetssätt med minskade krav på samordning. Det medför att de kan samarbeta med de datamängder de behöver. Den lösning som passade bäst utifrån dessa kriterier var Mutex., This paper is intended to study different aspects and take them in consideration to create a foundation for the developers to improve a multi-user environment. The purpose was to evaluate how to develop multi-user systems at a conceptual level with the technical aspects and describe how the users were affected by this. The study is based on multiple workshops and interviews. The writers have also been educated on how the system is used by the users and how the system was built, at two separate occasions. Based on this, criterias were made and these were valued against different techniques. These techniques are Mutex, Semaphores and Oracle Tuxedo. The criterias were considered and conceptual models were made to visualize the solution. The different techniques all live up to the constraints from the hardware and software of the case study, like the programming language C# and a database from Oracle. In a cooperation between the developers and users have the level of the solution been defined, where the solution ease the problems enough and still not too complex to implement. There have also been a few directions on the performance of the system. The solution should not be affecting the performance significantly. The users’working methods are not going to be particularly affected. The main part of the cooperation are not as needed as before. They can work in the same dataset concurrent in the datasets they required. On this basis the best technique to use in this case was Mutex.

To solve current environmental challenges such as biodiversity loss, climate change, and rapid conversion of natural areas due to urbanization and agricultural expansion, researchers are increasingly leveraging large, multi-scale, multi-temporal, and multi-dimensional geospatial data. In response, a rapidly expanding array of collaborative geospatial tools is being developed to help collaborators share data, code, and results. Successful navigation of these tools requires users to understand their strengths, synergies, and weaknesses. In this paper, we identify the key components of a collaborative Spatial Data Science workflow to develop a framework for evaluating the various functional aspects of collaborative geospatial tools. Using this framework, we then score thirty-one existing collaborative geospatial tools and apply a cluster analysis to create a typology of these tools. We present this typology as a map of the emergent ecosystem and functional niches of collaborative geospatial tools. We identify three primary clusters of tools composed of eight secondary clusters across which divergence is driven by required infrastructure and user involvement. Overall, our results highlight how environmental collaborations have benefitted from the use of these tools and propose key areas of future tool development for continued support of collaborative geospatial efforts.

The multi-key, or multi-user, setting challenges cryptographic algorithms to maintain high levels of security when used with many different keys, by many different users. Its significance lies in the fact that in the real world, cryptography is rarely used with a single key in isolation. A folklore result, proved by Bellare, Boldyreva, and Micali for public-key encryption in EUROCRYPT 2000, states that the success probability in attacking any one of many independently keyed algorithms can be bounded by the success probability of attacking a single instance of the algorithm, multiplied by the number of keys present. Although sufficient for settings in which not many keys are used, once cryptographic algorithms are used on an internet-wide scale, as is the case with TLS, the effect of multiplying by the number of keys can drastically erode security claims. We establish a sufficient condition on cryptographic schemes and security games under which multi-key degradation is avoided. As illustrative examples, we discuss how AES and GCM behave in the multi-key setting, and prove that GCM, as a mode, does not have multi-key degradation. Our analysis allows limits on the amount of data that can be processed per key by GCM to be significantly increased. This leads directly to improved security for GCM as deployed in TLS on the Internet today.

Gaze information provides indication of users focus which complements remote collaboration tasks, as distant users can see their partner’s focus. In this paper, we apply gaze for co-located collaboration, where users’ gaze locations are presented on the same display, to help collaboration between partners. We integrated various types of gaze indicators on the user interface of a collaborative search system, and we conducted two user studies to understand how gaze enhances coordination and communication between co-located users. Our results show that gaze indeed enhances co-located collaboration, but with a trade-off between visibility of gaze indicators and user distraction. Users acknowledged that seeing gaze indicators eases communication, because it let them be aware of their partner’s interests and attention. However, users can be reluctant to share their gaze information due to trust and privacy, as gaze potentially divulges their interests., Pattern Recognition and Bioinformatics

To solve current environmental challenges such as biodiversity loss, climate change, and rapid conversion of natural areas due to urbanization and agricultural expansion, researchers are increasingly leveraging large, multi-scale, multi-temporal, and multi-dimensional geospatial data. In response, a rapidly expanding array of collaborative geospatial tools is being developed to help collaborators share data, code, and results. Successful navigation of these tools requires users to understand their strengths, synergies, and weaknesses. In this paper, we identify the key components of a collaborative Spatial Data Science workflow to develop a framework for evaluating the various functional aspects of collaborative geospatial tools. Using this framework, we then score thirty-one existing collaborative geospatial tools and apply a cluster analysis to create a typology of these tools. We present this typology as a map of the emergent ecosystem and functional niches of collaborative geospatial tools. We identify three primary clusters of tools composed of eight secondary clusters across which divergence is driven by required infrastructure and user involvement. Overall, our results highlight how environmental collaborations have benefitted from the use of these tools and propose key areas of future tool development for continued support of collaborative geospatial efforts.

The multi-key, or multi-user, setting challenges cryptographic algorithms to maintain high levels of security when used with many different keys, by many different users. Its significance lies in the fact that in the real world, cryptography is rarely used with a single key in isolation. A folklore result, proved by Bellare, Boldyreva, and Micali for public-key encryption in EUROCRYPT 2000, states that the success probability in attacking any one of many independently keyed algorithms can be bounded by the success probability of attacking a single instance of the algorithm, multiplied by the number of keys present. Although sufficient for settings in which not many keys are used, once cryptographic algorithms are used on an internet-wide scale, as is the case with TLS, the effect of multiplying by the number of keys can drastically erode security claims. We establish a sufficient condition on cryptographic schemes and security games under which multi-key degradation is avoided. As illustrative examples, we discuss how AES and GCM behave in the multi-key setting, and prove that GCM, as a mode, does not have multi-key degradation. Our analysis allows limits on the amount of data that can be processed per key by GCM to be significantly increased. This leads directly to improved security for GCM as deployed in TLS on the Internet today.

Gaze information provides indication of users focus which complements remote collaboration tasks, as distant users can see their partner’s focus. In this paper, we apply gaze for co-located collaboration, where users’ gaze locations are presented on the same display, to help collaboration between partners. We integrated various types of gaze indicators on the user interface of a collaborative search system, and we conducted two user studies to understand how gaze enhances coordination and communication between co-located users. Our results show that gaze indeed enhances co-located collaboration, but with a trade-off between visibility of gaze indicators and user distraction. Users acknowledged that seeing gaze indicators eases communication, because it let them be aware of their partner’s interests and attention. However, users can be reluctant to share their gaze information due to trust and privacy, as gaze potentially divulges their interests., Pattern Recognition and Bioinformatics

[ES] El objetivo de este trabajo final de grado es implementar un sistema para permitir a uno o más usuarios interaccionar con las aplicaciones mediante punteros láser. Varios usuarios podrán usar sendos punteros como dispositivos apuntadores para trabajar sobre una superficie de trabajo. Dicha superficie de trabajo será normalmente la salida de un proyector. Por medio de una webcam, el sistema es capaz de detectar e identificar uno o más punteros láser, basándose en parámetros como el color para distinguirlos entre sí. El tracking de los punteros obtiene su posición, área, color, etc., teniendo en cuenta su historia. Nuestro sistema utiliza el protocolo TUIO para enviar los mensajes con esa información a una aplicación cliente, que será la encargada de implementar la salida gráfica dependiendo de la posición de los punteros. Dicho protocolo es ampliamente utilizado en las aplicaciones multitáctiles., [EN] The aim of this final degree project is to implement a system to allow one or more users interact with applications using laser pointers. Multiple users can use two separate pointers as pointing devices to work on a work surface. This working surface is normally the output of a projector. By means of a webcam, the system is able to detect and identify one or more laser pointers, based on parameters such as color to distinguish between them. The tracking pointers gets his position, area, color, etc., given its history. Our system uses the TUIO protocol to send messages with that information to a client application, which will be responsible for implementing the graphical output depending on the position of the pointers. This protocol is widely used in multitouch applications.

We study a full duplex (FD) multiple-input multiple-output (MIMO) cognitive cellular network, in which a secondary base-station (BS) operating in FD mode serves multiple uplink (UL) and downlink (DL) secondary users (SUs) operating in half-duplex (HD) mode simultaneously. The spectrum is shared between secondary and primary networks, and thus uplink SUs and secondary BS generate interference on primary users (PUs). We assume that the channel state information (CSI) available at the transmitters is imperfect, and the errors of the CSI are assumed to be norm bounded. Under the impact of channel uncertainty, we address the robust minimization of the sum of mean-squared-errors (MSE) of all estimated symbols subject to power constraints at the uplink SUs and secondary BS, and interference constraints projected to each PU. We show that this problem can be cast as a Semidefinite programming (SDP), and joint design of transceiver matrices can be obtained through an iterative algorithm. Numerical results are presented to show the effectiveness and robustness of the proposed robust algorithm. © 2016 IEEE.

[ES] El objetivo de este trabajo final de grado es implementar un sistema para permitir a uno o más usuarios interaccionar con las aplicaciones mediante punteros láser. Varios usuarios podrán usar sendos punteros como dispositivos apuntadores para trabajar sobre una superficie de trabajo. Dicha superficie de trabajo será normalmente la salida de un proyector. Por medio de una webcam, el sistema es capaz de detectar e identificar uno o más punteros láser, basándose en parámetros como el color para distinguirlos entre sí. El tracking de los punteros obtiene su posición, área, color, etc., teniendo en cuenta su historia. Nuestro sistema utiliza el protocolo TUIO para enviar los mensajes con esa información a una aplicación cliente, que será la encargada de implementar la salida gráfica dependiendo de la posición de los punteros. Dicho protocolo es ampliamente utilizado en las aplicaciones multitáctiles., [EN] The aim of this final degree project is to implement a system to allow one or more users interact with applications using laser pointers. Multiple users can use two separate pointers as pointing devices to work on a work surface. This working surface is normally the output of a projector. By means of a webcam, the system is able to detect and identify one or more laser pointers, based on parameters such as color to distinguish between them. The tracking pointers gets his position, area, color, etc., given its history. Our system uses the TUIO protocol to send messages with that information to a client application, which will be responsible for implementing the graphical output depending on the position of the pointers. This protocol is widely used in multitouch applications.

[ES] El objetivo de este trabajo final de grado es implementar un sistema para permitir a uno o más usuarios interaccionar con las aplicaciones mediante punteros láser. Varios usuarios podrán usar sendos punteros como dispositivos apuntadores para trabajar sobre una superficie de trabajo. Dicha superficie de trabajo será normalmente la salida de un proyector. Por medio de una webcam, el sistema es capaz de detectar e identificar uno o más punteros láser, basándose en parámetros como el color para distinguirlos entre sí. El tracking de los punteros obtiene su posición, área, color, etc., teniendo en cuenta su historia. Nuestro sistema utiliza el protocolo TUIO para enviar los mensajes con esa información a una aplicación cliente, que será la encargada de implementar la salida gráfica dependiendo de la posición de los punteros. Dicho protocolo es ampliamente utilizado en las aplicaciones multitáctiles., [EN] The aim of this final degree project is to implement a system to allow one or more users interact with applications using laser pointers. Multiple users can use two separate pointers as pointing devices to work on a work surface. This working surface is normally the output of a projector. By means of a webcam, the system is able to detect and identify one or more laser pointers, based on parameters such as color to distinguish between them. The tracking pointers gets his position, area, color, etc., given its history. Our system uses the TUIO protocol to send messages with that information to a client application, which will be responsible for implementing the graphical output depending on the position of the pointers. This protocol is widely used in multitouch applications.

We study a full duplex (FD) multiple-input multiple-output (MIMO) cognitive cellular network, in which a secondary base-station (BS) operating in FD mode serves multiple uplink (UL) and downlink (DL) secondary users (SUs) operating in half-duplex (HD) mode simultaneously. The spectrum is shared between secondary and primary networks, and thus uplink SUs and secondary BS generate interference on primary users (PUs). We assume that the channel state information (CSI) available at the transmitters is imperfect, and the errors of the CSI are assumed to be norm bounded. Under the impact of channel uncertainty, we address the robust minimization of the sum of mean-squared-errors (MSE) of all estimated symbols subject to power constraints at the uplink SUs and secondary BS, and interference constraints projected to each PU. We show that this problem can be cast as a Semidefinite programming (SDP), and joint design of transceiver matrices can be obtained through an iterative algorithm. Numerical results are presented to show the effectiveness and robustness of the proposed robust algorithm. © 2016 IEEE.

We study a full duplex (FD) multiple-input multiple-output (MIMO) cognitive cellular network, in which a secondary base-station (BS) operating in FD mode serves multiple uplink (UL) and downlink (DL) secondary users (SUs) operating in half-duplex (HD) mode simultaneously. The spectrum is shared between secondary and primary networks, and thus uplink SUs and secondary BS generate interference on primary users (PUs). We assume that the channel state information (CSI) available at the transmitters is imperfect, and the errors of the CSI are assumed to be norm bounded. Under the impact of channel uncertainty, we address the robust minimization of the sum of mean-squared-errors (MSE) of all estimated symbols subject to power constraints at the uplink SUs and secondary BS, and interference constraints projected to each PU. We show that this problem can be cast as a Semidefinite programming (SDP), and joint design of transceiver matrices can be obtained through an iterative algorithm. Numerical results are presented to show the effectiveness and robustness of the proposed robust algorithm.

The topic is "Low-latency communication for machine-type communication in LTE-A" and need to be specified in more detail., This final project focus on designing and evaluating a resource management scheme for a multi-user generalized frequency division multiplexing (GFDM) system, when a frequency selective fading channel and adaptive modulation is used. GFDM with adaptive subcarrier, sub-symbol and power allocation are considered. Assuming that the transmitter has a perfect knowledge of the instantaneous channel gains for all users, I propose a multi-user GFDM subcarrier, sub-symbol and power allocation algorithm to minimize the total transmit power. This work analyzes the performance of using a specific set of parameters for aligning GFDM with long term evolution (LTE) grid. The results show that the performance of the proposed algorithm using GFDM is closer to the performance of using OFDM and outperforms multiuser GFDM systems with static frequency division multiple access (FDMA) techniques which employ fixed subcarrier allocation schemes. The advantage between GFDM and OFDM is that the latency of the system can be reduced by a factor of 15 if independent demodulation is considered., El objetivo de este proyecto final es el de diseñar y evaluar un esquema para administrar los recursos de un sistema multi-usuario donde se utiliza generalized frequency division multiplexing (GFDM), cuando el canal es de frequencia de desvanecimiento selectivo y se utiliza modulación adaptiva. Consideramos un sistema GFDM con subportadora, sub-símbolo i asignación de potencia adaptiva. Asumiendo que el transmisor conoce perfectamente el estado del canal para todos los usuarios, propongo un algoritmo que asigna los recursos de forma que la potencia total de transmisión es mínima. Este trabajo analiza la eficiencia de utilizar un grupo de parámetros concretos para alinear el sistema GFDM con el sistema de LTE. Los resultados muestran que el comportamiento del algoritmo en GFDM es muy similar al de OFDM, pero mucho mayor que cuando se compara con sistemas de asignación de recursos estáticos., L’objectiu d’aquest projecte final es dissenyar i avaluar un esquema per administrar els recursos per a un sistema multi-usuari fent servir generalized frequency division multiplexing (GFDM), quan el canal es de freqüència esvaniment selectiu i es fa servir modulació adaptativa. Considerem un sistema GFDM amb subportadora, sub-símbol i assignació de potencia adaptativa. Assumint que el transmissor coneix perfectament l’estat del canal per tots els usuaris, proposo un algoritme que assigna els recursos de forma que la potencia total de transmissió es la mínima. Aquest treball analitza l’eficiència de fer servir un grup de paràmetres concrets per tal d’alinear el sistema GFDM amb el sistema de LTE. Els resultats mostren que el comportament de l’algoritme en GFDM es molt similar al de OFDM i que millora bastant els resultats quan el comparem amb sistemes d’assignament de recursos estàtics.

A multiuser asynchronous visible light communication system adopting DFT spread (DFS-) OFDM/OQAM is proposed and experimentally demonstrated. Both high spectral locality and low peak-to-average power ratio are achieved with DFTS-OFDM/OQAM, which improves system’s transmission performance., QC 20201229

Research on mobile collocated interactions has been looking at situations in which collocated users engage in collaborative activities using their mobile devices, thus going from personal/individual toward shared/multiuser experiences and interactions. However, computers are getting smaller, more powerful, and closer to our bodies. Therefore, mobile collocated interactions research, which originally looked at smartphones and tablets, will inevitably move towards fully integrated wearable technologies. The focus of this workshop is to bring together a community of researchers, designers and practitioners to explore the potential of extending mobile collocated interactions from, through and around the body using wearable technologies., 17th International Conference on Human-Computer Interaction with Mobile Devices and Services Adjunct, MobileHCI ; Conference date: 24-08-2015 Through 27-08-2015

T(ether) is a spatially-aware display system for multi-user, collaborative manipulation and animation of virtual 3D objects. The handheld display acts as a window into virtual reality, providing users with a perspective view of 3D data. T(ether) tracks users' heads, hands, fingers and pinching, in addition to a handheld touch screen, to enable rich interaction with the virtual scene. We introduce gestural interaction techniques that exploit proprioception to adapt the UI based on the hand's position above, behind or on the surface of the display. These spatial interactions use a tangible frame of reference to help users manipulate and animate the model in addition to controlling environment properties. We report on initial user observations from an experiment for 3D modeling, which indicate T(ether)'s potential for embodied viewport control and 3D modeling interactions., QC 20141219

New PHY and MAC layer enhancements have been introduced in different IEEE 802.11 WLAN standards. These improvements have given birth to a wide range of bandwidth channels (up to 160MHz) and very high transmission data rates (> 1Gbps) to keep up with current and up-coming multimedia applications. The major reason for the inefficiency of different WLANs is that the current MAC layer randomly allocates the entire channel to only one user as a single resource. Thus, one way to significantly improve WLAN performance is to effectively reduce the channel width and create different sized sub-channels. Based on the user's channel conditions and QoS requirements, the PHY layer resources can be dynamically allocated to several users at the same time. In this paper, we present a novel dynamic sub-channels access approach, titled DMU-Access1, with new features suitable for the forthcoming large bandwidth WLAN products. We shall evaluate its performance compared to state-of-the-art systems, using the simulator NS-3 under a variety of network conditions. Our experiments will then demonstrate that our scheme enhances IEEE 802.11 devices' performance with a much higher degree of throughput. © 2014 IEEE.

New PHY and MAC layer enhancements have been introduced in different IEEE 802.11 WLAN standards. These improvements have given birth to a wide range of bandwidth channels (up to 160MHz) and very high transmission data rates (> 1Gbps) to keep up with current and up-coming multimedia applications. The major reason for the inefficiency of different WLANs is that the current MAC layer randomly allocates the entire channel to only one user as a single resource. Thus, one way to significantly improve WLAN performance is to effectively reduce the channel width and create different sized sub-channels. Based on the user's channel conditions and QoS requirements, the PHY layer resources can be dynamically allocated to several users at the same time. In this paper, we present a novel dynamic sub-channels access approach, titled DMU-Access1, with new features suitable for the forthcoming large bandwidth WLAN products. We shall evaluate its performance compared to state-of-the-art systems, using the simulator NS-3 under a variety of network conditions. Our experiments will then demonstrate that our scheme enhances IEEE 802.11 devices' performance with a much higher degree of throughput. © 2014 IEEE.