A machine learning approach to The Big Five Personality Test

Dissertação de mestrado em Engenharia InformáticaOne of the most accurate personality assessments available is the Goldberg’s ’The Big Five Personality Test’, which measures the five OCEAN dimensions: Openness, Conscientiousness, Extraversion, Agreeableness and Neuroticism. This assessment is performed by presenting a total of forty adjectives requesting the subject to rate each word using a scale of 1 to 9 indicating whether it accurately (9) describes herself or not (1). Nonetheless, scientific research has shown that this test may, accurately, suggest personality traits such as aggressive reactions, work performance, fitness on specific expertise areas and also mental illnesses. However, one big disadvantage of this test, it simply takes too much time to perform, which can result on undesirable measurements. Indeed, several developments have been done in order to reduce the required effort to perform this test, an example is The Mini Marker Test by Saucier. This study aims to propose a viable shorter alternative to this by applying machine learning techniques, i.e., although measurement precision may be reduced, is it possible to build a much shorter version losing as little precision as possible by just requiring the subject to select the adjectives that characterise him the most? For this study, it was developed a platform to collect data, requesting both the subject to rate each adjective but also to select those he most identifies with. With this, the available data contains both ratings and the selections of the words that most characterise the subject. Three different machine learning architectures are developed and tested. Both regression and classification approaches are considered. The main input for these architectures are the words selected by each evaluated subject. Data collected by this work showed to be insufficient, requiring the use of data augmentation techniques. For this, different versions are proposed, one including the use of frequent itemset mining techniques. The proposed machine learning architectures shown a very high precision, with an RMSE of around 7%. The results show the proposed solutions to be able to perform a shorter version of this test with a minimum precision loss. It was also possible to define a list of common sets of selected words. Further research can be performed mainly on two different streamlines, i.e., strength the data collection process and develop an even shorter version of this test.Uma das avaliações de personalidade mais precisas foi criada por Goldberg, chamada 'The Big Five Personality Test', que mede um total de cinco dimensões denominadas de OCEAN: Openness, Conscientiousness, Extraversion, Agreeableness and Neuroticism. A avaliaçao em causa é realizada apresentando um total de quarenta adjetivos a um individuo solici-tando lhe que classifique cada uma das palavras usando uma escala de a a 9, indicando se esta o descreve de forma exata (9) ou não (1). Assim sendo, estudos científicos sugerem que este teste poderá, de forma precisa, indicar outros traços da personalidade, tais como reações agressivas, desempenho no trabalho, aptidão para áreas de especialidade e doenças mentais. No entanto, uma grande desvantagem deste teste, é que este pode ser demasiado extenso e demorado, podendo gerar resultados indesejados. Na verdade, múltiplos desenvolvimentos foram feitos de modo a reduzir o esforço necessário para a realização do mesmo. Este estudo pretende assim propor uma alternativa mais curta e viável aplicando técnicas de machine learning, isto é, apesar da precisão dos resultados poder ser degradada, é possível construir uma versão muito mais curta com o mínimo possível de degradação da qualidade dos resultados apenas solicitando ao sujeito que este selecione os adjetivos que melhor o caracterizam? Para este estudo, foi desenvolvida uma plataforma para recolha de dados, solicitando ao individuo tanto para classificar cada adjetivo, usando a escala, como também para selecionar aqueles com que este mais se identifica. Assim, os dados disponíveis contém tanto as escalas como a seleção das palavras que mais caracterizam cada um dos sujeitos. Três diferentes arquiteturas de machine learning são desenvolvidas e testadas. Tanto abordagens de regressão como classificação são consideradas. O principal input para estas arquiteturas é a seleção de cada uma das palavras por parte dos sujeitos avaliados. Os dados recolhidos durante este estudo demonstraram ser insuficientes, exigindo o uso de técnicas de data augmentation. Nesse sentido, diferentes versões são propostas, sendo que uma delas incluí o uso de técnicas de frequent itemset mining. As arquiteturas de machine learning propostas apresentaram uma precisão bastante elevada nos resultados, com um RMSE de cerca de 7%. Os resultados obtidos mostram que as soluções propostas são capazes de gerar uma versão reduzida do teste em causa com uma degradação mínima dos resultados. Foi também possível definir uma lista de conjuntos frequentes de palavras selecionadas. Desenvolvimentos futuros podem ser feitos em duas direções distintas, isto é, melhorar o processo de recolha de dados ou desenvolver uma versão ainda mais reduzida deste teste

Analysis and design of efficient techniques for video transmission in IEEE 802.11 wireless ad hoc networks

[EN] Wireless mobile ad ho networks, also known as MANETs, are omposed by independent mobile stations that ommuni ate without requiring any sort of infrastru ture for support. These networks are hara terized by variable bandwidth values and frequent path breaks, whi h are due to hannel noise, interferen e between stations and mobility. Su h fa tors require significant adaptation apabilites at different levels of the proto ol suites employed, enabling stations to qui kly respond to fast- hanging network onditions. Resear h on the most adequate proto- ols for the physi al, MAC and routing layers is still on-going, though some basi onsensus has already been rea hed and several testbeds have been setup around the world. To deploy real-time multimedia servi es, namely voi e and video, on top of su h an unreliable network environment is a very hallenging task. In this thesis we propose to a hieve that goal starting from urrently available Wi-Fi te hnology, and gradually finding the most adequate enhan ements to ea h proto ol layer of interest; we then ombine these enhan ements until we a hieve a omplete QoS framework for ad ho networks. By using urrently available te hnology we assure that the proposal of this thesis has an inherent high-level of appli ability on real life environments. Sin e our working field fo uses on video transmission over wireless ad ho networks, we will show how it is possible to support several QoS- onstrained video streams in MANET environments hara terized by moderate to high mobility levels, and by a significant amount of best efort traffic[ES] Las redes inalámbricas ad hoc, también conocidas como redes MANET, están compuestas por un conjunto de estaciones móviles independientes capaces de omunicarse entre sí sin necesidad de ningún tipo de infraestructura común de comunicaciones. Estas redes se caracterizan por tener un ancho de banda variable y pérdidas frecuentes de ruta que se pueden atribuir al ruido del anal inalámbrico, a la interferencia entre las estaciones móviles o bien a la movilidad de las estaciones. Dichos factores requieren una gran capacidad de adaptación en las diferentes capas de la arquitectura de protocolos, permitiendo a una estación responder rápidamente a posibles cambios bruscos en las condiciones de la red. A pesar de que aún se están realizando trabajos de investigación en bus a de los protocolos más adecuados para las capas físicas, a eso al medio (MAC) y encaminamiento, ha sido posible llegar a un nivel básico de consenso, lo cual ha permitido el despliegue de plataformas y entornos aplicados que utilizan tecnología de red MANET. Ofrecer servicios multimedia, como voz y vídeo, en redes con tan poca habilidad es un desafío importante. En esta tesis nos proponemos alcanzar este objetivo partiendo de la tecnología Wi-Fi actualmente disponible, encontrando de forma paulatina las mejoras más importantes en las diferentes capas de la arquitectura de red, para llegar, finalmente, a una solución integrada capaz de ofrecer calidad de servicio (QoS) en las redes MANET. Al utilizar la tecnología que disponemos actualmente nos aseguramos que las propuestas de esta tesis tengan un alto grado de aplicabilidad en entornos reales. Ya que la línea de trabajo de la tesis está aplicada a la transmisión de vídeo en redes MANET, demostraremos que es posible ofrecer calidad de servicio a varios flujos de vídeo en una red MANET caracterizada por altos grados de movilidad en sus nodos y un nivel significativo de tráfico o de tipo best effortTavares De Araujo Cesariny Calafate, CM. (2006). Analysis and design of efficient techniques for video transmission in IEEE 802.11 wireless ad hoc networks [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/135282TESI

On the Use of Mobile Sensors for Estimating City-Wide Pollution Levels

©2015 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.Obtaining detailed pollution maps for urban environments is an effort that is gathering much interest by allowing to better regulate traffic and protect citizens from hazardous conditions. However, the scarcity of pollution sensors prevents obtaining the desired degree of detail, requiring alternative solutions to be deployed. In this paper we explore the concept of mobile pollution sensing by studying the feasibility of equipping buses with ozone measurement hardware to estimate ozone patterns for the city of Compiègne. Overall, we achieve accurate estimations, with error values typically ranging from 2% to 10%. Compared to solutions based on deploying static sensors on the different bus stops available, we find that the proposed mobile sensing approach is able to provide a degree of accuracy comparable to deploying tens of static sensors, substantially reducing costs and management.This work was carried out and funded in the framework of the Labex MSZT. It was supported by the French Government, through the program "Investments for the future” managed by the National Agency for Research (Reference ANR-11-IDEX-0004-02). This work was partially funded by the Celtic Plus CoMoSeF project "Cooperative mobility for the services of the future". The authors thank the Agglomération de la Région de Compiégne (ARC).Tavares De Araujo Cesariny Calafate, CM.; Ducourthial, B. (2015). On the Use of Mobile Sensors for Estimating City-Wide Pollution Levels. IEEE. doi:10.1109/IWCMC.2015.7289093

Unmanned Aerial Vehicles-Platforms, Applications, Security and Services

Tavares De Araujo Cesariny Calafate, CM.; Tropea, M. (2020). Unmanned Aerial Vehicles-Platforms, Applications, Security and Services. Electronics. 9(6):1-3. https://doi.org/10.3390/electronics9060975S1396Stellin, M., Sabino, S., & Grilo, A. (2020). LoRaWAN Networking in Mobile Scenarios Using a WiFi Mesh of UAV Gateways. Electronics, 9(4), 630. doi:10.3390/electronics9040630Hiba, A., Sántha, L. M., Zsedrovits, T., Hajder, L., & Zarandy, A. (2020). Onboard Visual Horizon Detection for Unmanned Aerial Systems with Programmable Logic. Electronics, 9(4), 614. doi:10.3390/electronics9040614Tropea, M., Fazio, P., De Rango, F., & Cordeschi, N. (2020). A New FANET Simulator for Managing Drone Networks and Providing Dynamic Connectivity. Electronics, 9(4), 543. doi:10.3390/electronics9040543Chen, C.-L., Deng, Y.-Y., Weng, W., Chen, C.-H., Chiu, Y.-J., & Wu, C.-M. (2020). A Traceable and Privacy-Preserving Authentication for UAV Communication Control System. Electronics, 9(1), 62. doi:10.3390/electronics9010062Khan, M. A., Qureshi, I. M., Ullah, I., Khan, S., Khanzada, F., & Noor, F. (2019). An Efficient and Provably Secure Certificateless Blind Signature Scheme for Flying Ad-Hoc Network Based on Multi-Access Edge Computing. Electronics, 9(1), 30. doi:10.3390/electronics9010030Wubben, J., Fabra, F., Calafate, C. T., Krzeszowski, T., Marquez-Barja, J. M., Cano, J.-C., & Manzoni, P. (2019). Accurate Landing of Unmanned Aerial Vehicles Using Ground Pattern Recognition. Electronics, 8(12), 1532. doi:10.3390/electronics8121532Zhou, Y., Wu, C., Wu, Q., Eli, Z. M., Xiong, N., & Zhang, S. (2019). Design and Analysis of Refined Inspection of Field Conditions of Oilfield Pumping Wells Based on Rotorcraft UAV Technology. Electronics, 8(12), 1504. doi:10.3390/electronics812150

Evaluation of network simulation and modelimg tools

Mestrado em Engenharia Electrónica e TelecomunicaçõesA crescente globalização da Internet e consequente procura de largura de banda nas redes IP existentes fez emergir a necessidade de um melhor planeamento das redes de telecomunicações. Tendo em vista esse fim foram criadas ferramentas aptas a auxiliar a gestão de redes, como software de monitorização, e em particular os simuladores de redes. Estes permitem a obtenção de resultados preciosos sem a consumo de recursos que a criação de uma testbed real requer. Um desses simuladores é o Opnet Modeler, um software comercial que possibilita a configuração de cenários a vários níveis, como as características dos protocolos, perfis de utilizadores e de mobilidade, ou a estrutura e dimensão da rede. Esta dissertação propôe-se a numa primeira parte a analisar vários aspectos respeitantes à utilização do Opnet Modeler no prisma do gestor de redes, em especial em redes à escala de Campus, explorando algumas das vantagens e lacunas na sua utilização para diversos fins, tais como o design ou restruturação de redes e a análise da qualidade de serviço de diferentes aplicações. Uma componente indispensável à gestão de redes é a previsão de qualidade de serviço. O facto do comportamento do tráfego numa rede variar devido a factores como a alteração do número de utilizadores ou dos seus perfis de tráfego, leva a que seja várias vezes necessário estimar o comportamento da rede sem o perfeito conhecimento desta ou dos seus recursos. O nível de tráfego actualmente desperdiçado devido a uma incorrecta estimativa por parte dos ISP’s da utilização de redes mais complexas representa ao mesmo tempo custos desnecessários e recursos subaproveitados. A procura de um modelo de tráfego que possibilite uma aproximação mais exacta dos parâmetros previstos em relação à realidade leva a que haja uma maior investigação nesta área. Nesta dissertação é testado um framework modelador que se baseia apenas em medições (ou resultados de simulações) de tráfego e correspondentes parâmetros de qualidade de serviço dos pontos de acesso da rede, sem o conhecimento a priori da matriz de tráfego e da topologia da rede, para prever a qualidade de serviço em condições distintas. ABSTRACT: The growing Internet globalization and consequent demand for bandwidth in the existing IP networks lead to the emerging need of a better network telecommunications planning. In order to accomplish that, apt network management tools were created, like monitoring software and network simulators, in particular. These allow the collection of precious results exempt of the resources consumption that the use of a real testbed would require. One of those simulators is Opnet Modeler, commercial software that allows to configure the scenarios at multiple levels, like protocol characteristics, profiles and mobility profiles, or the network size and structure. This dissertation proposes to analyze various aspects related to Opnet Modeler use in a network manager perspective, in particular in Campus scale networks, aiming to explore its advantages and gaps when used for goals such as network design or restructuration and for different services’ QoS analysis. One essential component in network management is QoS prediction. The fact that the network traffic behavior varies due to details like the change in the number of users or their traffic profiles, many times leads to the need of assessing the network behavior without the perfect knowledge of the network or its resources. The currently wasted bandwidth by the ISP’s and network managers due to an incorrect assessment of the utilization in more complex networks represents unnecessary costs and wasted resources. The pretension to obtain a traffic model that allows a more exact approximation of the predicted parameters relatively to the reality lead to a major increase in the research in this area. In this dissertation, the evluation of a modeling framework is performed; that model, based only in traffic measurements (or simulation results) and corresponding QoS parameters at the network access points, that is, without the a priori knowledge of the network’s traffic matrix and topology, is able to predict the network’s QoS for different conditions

Distribuição de vídeo para grupos de utilizadores em redes móveis heterogéneas19

The evolutions veri ed in mobile devices capabilities (storage capacity, screen resolution, processor, etc.) over the last years led to a signi cant change in mobile user behavior, with the consumption and creation of multimedia content becoming more common, in particular video tra c. Consequently, mobile operator networks, despite being the target of architectural evolutions and improvements over several parameters (such as capacity, transmission and reception performance, amongst others), also increasingly become more frequently challenged by performance aspects associated to the nature of video tra c, whether by the demanding requirements associated to that service, or by its volume increase in such networks. This Thesis proposes modi cations to the mobile architecture towards a more e cient video broadcasting, de ning and developing mechanisms applicable to the network, or to the mobile terminal. Particularly, heterogeneous networks multicast IP mobility supported scenarios are focused, emphasizing their application over di erent access technologies. The suggested changes are applicable to mobile or static user scenarios, whether it performs the role of receiver or source of the video tra c. Similarly, the de ned mechanisms propose solutions targeting operators with di erent video broadcasting goals, or whose networks have di erent characteristics. The pursued methodology combined an experimental evaluation executed over physical testbeds, with the mathematical evaluation using network simulation, allowing the veri cation of its impact on the optimization of video reception in mobile terminalsA evolução veri cada nas características dos dispositivos moveis (capacidade de armazenamento, resolução do ecrã, processador, etc.) durante os últimos anos levou a uma alteração signi cativa nos comportamentos dos utilizadores, sendo agora comum o consumo e produção de conteúdos multimédia envolvendo terminais móveis, em particular o tráfego vídeo. Consequentemente, as redes de operador móvel, embora tendo também sido alvo constante de evoluções arquitecturais e melhorias em vários parâmetros (tais como capacidade, ritmo de transmissão/recepção, entre outros), vêemse cada vez mais frequentemente desa adas por aspectos de desempenho associados à natureza do tráfego de vídeo, seja pela exigência de requisitos associados a esse serviço, quer pelo aumento do volume do mesmo nesse tipo de redes. Esta Tese propôe alterações à arquitetura móvel para a disseminação de vídeo mais e ciente, de nindo e desenvolvendo mecanismos aplicáveis à rede, ou ao utilizador móvel. Em particular, são focados cenários suportados por IP multicast em redes móveis heterogéneas, isto é, com ênfase na aplicação destes mecanismos sobre diferentes tecnologias de acesso. As alterações sugeridas aplicam-se a cenários de utilizador estático ou móvel, sendo este a fonte ou receptor do tráfego vídeo. Da mesma forma, são propostas soluções tendo em vista operadores com diferentes objectivos de disseminação de vídeo, ou cujas redes têm diferentes características. A metodologia utilizada combinou a avaliação experimental em testbeds físicas com a avaliação matemática em simulações de redes, e permitiu veri car o impacto sobre a optimização da recepção de vídeo em terminais móveisPrograma Doutoral em Telecomunicaçõe

Breaking persistent working group partnerships: a social experiment

Facing multidisciplinary projects is becoming quite common in companies worldwide, meaning that experts from a specific area must team up with experts from other areas in a dynamic, ad hoc manner. For a professional to meet such requirements successfully, it is important that teamwork skills are developed during college. However, such issue is usually not addressed thoroughly, and most students end up teaming with the same partners over and over again, thereby failing to achieve the critical adaptability skills expected from them. To address this drawback, in this paper we present the results of a study where students were forced to team up with other partners based on the results of a computer networking skills-ranking exam. Experimental results confirm the repeating pattern in terms of past partnerships, and student resistance to partner changes. On the positive side, results show that having new partners indeed help at achieving a more even task distribution, and that students are moderately aware of the upcoming challenges in their future professional activity, recognizing the benefits of teaming up with new people.This work was partially supported by the School of Informatics (ETSINF) and the Department of Computer Engineering (DISCA) at the Universitat Politècnica de València.Tavares De Araujo Cesariny Calafate, CM.; Arlandis, J.; Torres Cortes, A. (2015). Breaking persistent working group partnerships: a social experiment. En INTED2015 Proceedings. IATED. 1329-1337. http://hdl.handle.net/10251/70447S1329133

QoS-RRC: Integrated QoS routing and resource provisioning mechanism for future internet

Generic Path (GP) is a new connectivity paradigm proposed to facilitate the inclusion of new applications and services abstracting communications between entities, regardless of their location or architectural layer. This paper enhances the GP architecture with a new mechanism integrating QoS-Routing and Resource Control (QoS-RRC) strategies to dynamically control GP session requirements regarding QoS and connectivity. This solution uses over-provisioning and admission control, and is aimed at multi-party time-sensitive sessions. Initial performance evaluation was carried out in Network Simulator v.2 (NS-2), showing capabilities in reducing overall signaling load in comparison with a value-added per-flow approach

Towards a Sustainable City for Cyclists: Promoting Safety through a Mobile Sensing Application

[EN] Riding a bicycle is a great manner to contribute to the preservation of our ecosystem. Cycling helps to reduce air pollution and traffic congestion, and so, it is one of the simplest ways to lower the environmental footprint of people. However, the cohabitation of cars and vulnerable road users, such as bikes, scooters, or pedestrians, is prone to cause accidents with serious consequences. In this context, technological solutions are sought that enable the generation of alerts to prevent these accidents, thereby promoting a safer city for these road users, and a cleaner environment. Alert systems based on smartphones can alleviate these situations since nearly all people carry such a device while traveling. In this work, we test the suitability of a smartphone based alert system, determining the most adequate communications architecture. Two protocols have been designed to send position and alert messages to/from a centralized server over 4G cellular networks. One of the protocols is implemented using a REST architecture on top of the HTTP protocol, and the other one is implemented over the UDP protocol. We show that the proposed alarm system is feasible regarding communication response time, and we conclude that the application should be implemented over the UDP protocol, as response times are about three times better than for the REST implementation. We tested the applications in real deployments, finding that drivers are warned of the presence of bicycles when closer than 150 m, having enough time to pay attention to the situation and drive more carefully to avoid a collision.This work was partially supported by the "Ministerio de Ciencia, Innovacion y Universidades, Programa Estatal de Investigacion, Desarrollo e Innovacion Orientada a los Retos de la Sociedad, Proyectos I+D+I 2018", Spain, under Grant RTI2018-096384-B-I00.Boronat, P.; Pérez-Francisco, M.; Tavares De Araujo Cesariny Calafate, CM.; Cano, J. (2021). Towards a Sustainable City for Cyclists: Promoting Safety through a Mobile Sensing Application. Sensors. 21(6):1-18. https://doi.org/10.3390/s2106211611821

Assessing the limits of centralized unmanned aerial vehicle conflict management in U-Space

There is an important growth of unmanned aerial vehicles (UAVs) performing planned missions in urban environments, which poses significant challenges to the research community. The possibility of collisions represents a critical challenge. UAVs can suffer collisions due to different causes external or internal to their flight plans. In this context, dynamic geo-fencing is a useful approach, whereby each UAV is able to provide a prediction of its future positions within a limited time. These predictions could be used to detect conflicts, allowing to dynamically modify the flight plans so as to avoid imminent collisions. In this work, a conflict detection algorithm/method is proposed, implemented and tested on a central server performing real-time conflict analysis for a large number of UAVs flying in the aerial space of a city (U-Space). The architecture assumes that UAVs send their future locations to a traffic controller. This controller compares the predicted positions of nearby vehicles to detect possible conflicts. The results of this work demonstrate the feasibility of the proposed conflict detection algorithm and its interest to improve the security and efficiency in U-Space environments. The server is able to track thousands of UAVs in real time with a conflict anticipation around 11 s.This work is derived from the following R&D projects: PID2021-122580NB-I00 and RTI2018-098156-B-C52, funded by MCIN/AEI/10.13039/501100011033, “ERDF A way of making Europe”, and SBPLY/19/180501/000159, funded by the Junta de Comunidades de Castilla-La Mancha (JCCM) and the EU through the European Regional Development Fund (ERDF-FEDER)