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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Wear-IT:implications of mobile & wearable technologies to human attention and interruptibility

Visuri, A. (Aku) 17 May 2019 (has links)
Abstract This thesis explores different ways of leveraging mobile sensing to understand how end users use and interact with their smart technologies, namely smartphones and smartwatches. These topics are extensively explored in other parallel research; however, numerous gaps still exist within the literature. The use of mobile sensing to collect quantified ground-truth information of device use in-the-wild is critical to collect unbiased experiences and usage traces. This thesis covers three main themes: (a) the way our affect influences our smartphone use, and how our smartphone usage can also be analysed from our usage habits; (b) revealing quantified exploration of smartwatch usage traits, and how these relate to smartphone use, and (c) novel ways to mitigate interruptions during smartphone or smartwatch use. The thesis begins by explaining the related work and the overall theme of mobile sensing and how device usage influences attention; it then proceeds to elaborate on the contribution of each included article to the overall scope of the thesis. The thesis then concludes with a summary of how the presented articles tie together in a broader scope. Considering the vast amount of research in this field by this thesis’ author as well as other researchers, this type of work can potentially improve the use of novel wearable technologies in the future. By the end of the thesis, the reader should have a broad understanding of what mobile sensing is, and how it can be applied to comprehensively uncover technology use as well as leveraging mobile sensing to enhance the use of technology. / Tiivistelmä Tässä väitöskirjassa tarkastellaan erilaisia tapoja hyödyntää mobiilikäytön tunnistamista ymmärtääkseen, miten loppukäyttäjät käyttävät ja ovat vuorovaikutuksessa älykkäiden teknologioidensa, esimerkiksi älypuhelimien ja älykellojen kanssa. Näitä aiheita tutkitaan laajasti muissa rinnakkaisissa tutkimuksissa, mutta kirjallisuudessa on vielä lukuisia aukkoja. Matkaviestinnän käytöstä kerätään kvantitatiiviset tiedot, jotka koskevat laitteen käyttöä luonnossa. Tämän tiedon kerääminen on kriittistä jotta voidaan kerätä puolueettomia kokemuksia ja käyttöjälkiä. Tässä työssä käsitellään kolmea pääteemaa; i) miten älypuhelinkäyttöömme vaikuttaa meidän mielialamme ja miten älypuhelinkäyttöämme voidaan analysoida käyttötapojen perusteella, ii) paljastaa älykellon käyttöominaisuuksien määrälliset tutkimukset ja miten nämä tulokset heijastuvat älypuhelimen käyttöön ja iii) uusia tapoja lieventää katkoksia älypuhelimen tai älykellon käytön aikana. Työ aloittaa selittämällä siihen liittyvää työtä ja mobiilin tunnistamisen yleistä teemaa ja sitä, miten laitteen käyttö vaikuttaa huomiokykyyn, ja jatkuu sitten yksityiskohtaisesti jokaisen mukana tulevan artikkelin osuuden yleiseen käsittelyyn. Työssä päädytään yhteenvetoon siitä, miten esitetyt artikkelit sitovat yhteen laajemman kokonaisuuden ja ottavat huomioon tämän alan tekijän ja muiden tutkijoiden tämän alan tutkimukset, ja miten tällaista työtä voitaisiin mahdollisesti parantaa edelleen tulevaisuudessa käyttämällä uusia tekniikoita. Työn päätyttyä lukijalla on laaja käsitys siitä, mitä mobiili-tunnistaminen on ja miten sitä voidaan soveltaa sekä teknologian käytön kattavaan paljastamiseen että mobiilidatan tunnistuksen hyödyntämiseen teknologian käytön tehostamiseksi.
12

Avaliação da exposição de ciclistas ao ruído em uma cidade média brasileira / Assessment of cyclists\' exposure to noise in a Brazilian medium-sized city

Thiago da Cunha Ramos 17 March 2017 (has links)
Embora muitas cidades brasileiras estejam gradualmente implementando infraestruturas cicloviárias, a exposição dos ciclistas ao ruído ainda não é vista como um elemento a ser considerado no processo de planejamento. A partir deste pressuposto, o objetivo deste estudo é avaliar a exposição dos ciclistas ao ruído em São Carlos, SP, cidade média brasileira na qual cerca de 244 mil habitantes, 107 mil carros e 25 mil motocicletas foram contados em 2016. O estudo envolveu os seguintes procedimentos: i) definições preliminares e ajustes relativos às campanhas de coleta de dados, ii) coleta de dados, iii) validação de dados, iv) cálculo de níveis de exposição ao ruído e v) avaliação da exposição dos ciclistas ao ruído. Foram analisadas duas rotas. A primeira apresentava infraestrutura cicloviária (ciclovias ou ciclofaixas), em alguns dos 12 setores considerados para análise. A segunda rota foi dividida em dois setores, ambos sem infraestrutura cicloviária, mas com um excelente potencial para atrair viagens de bicicleta devido à localização privilegiada da área na cidade. A exposição ao ruído foi classificada de acordo com a percentagem média de valores de SEL (Sound Exposure Level) acima de 85 dBA e de acordo com valores de Lnp (Nível de Poluição Sonora). De maneira geral, os níveis de exposição dos ciclistas ao ruído foram classificados como \"muito alto\" ou \"alto\" em todas as 14 subdivisões das duas rotas, três das quais foram classificados como insalubres. Além disso, mesmo as seções com os menores valores de Lnp apresentaram quase metade das viagens para coleta de dados classificadas como \"muito altas\". É importante destacar que os locais, das partes mais ruidosas das duas rotas, tinham características distintas. Os trechos mais ruidosos da primeira rota foram registrados em uma ciclovia localizada ao longo de uma avenida larga, que margeia um rio e é cercada por áreas verdes, mas onde o limite de velocidade para carros é de 60 km/h. Há claramente um conflito aqui, dado que, apesar das condições de circulação seguras proporcionadas pela ciclovia e o agradável ambiente visual encontrado nas proximidades do rio, as condições locais de ruído não eram nada favoráveis aos ciclistas. Em termos de comparação, porém, a seção mais ruidosa da outra rota é ainda pior. Além dos altos níveis de exposição ao ruído, a área é insegura e pouco agradável para os ciclistas devido à circulação em condições de tráfego misto. Por outro lado, é convenientemente localizado em termos de acessibilidade, o que mostra uma vez mais a complexidade envolvida no processo de planejamento de novas infraestruturas cicloviárias. / Although many Brazilian cities are gradually implementing cycling infrastructures, the cyclists\' exposure to noise is not yet seen as an element to be considered in the planning process. With this assumption as a starting point, the objective of this study is to assess cyclists\' exposure to noise in São Carlos, SP, a Brazilian medium-sized city in which around 244,000 inhabitants, 107,000 cars and 25,000 motorcycles were counted in 2016. The study involved the following procedures: i) preliminary definitions and adjustments regarding the data collection campaigns, ii) data collection, iii) data validation, iv) calculation of noise exposure levels, and v) assessment of cyclists\' exposure to noise. Two routes have been analyzed. The first one had dedicated cycling infrastructure, i.e., cycleways and cyclelanes, in some of the 12 sectors considered for analysis. The second route was split in two sectors, both without dedicated cycling infrastructure but with an excellent potential for attracting cycling trips due to the privileged location of the area in the city. Noise exposure was classified according to the average percentage of Sound Exposure Level (SEL) values above 85 dBA and according to the values of noise pollution levels (Lnp). In general, all sections of the two routes were classified as either \"very high\" or \"high\" regarding the cyclists\' exposure to noise, and 3 out of the total 14 sectors were classified as unhealthy. Furthermore, even the sections with the lowest noise exposure levels had nearly half of the data collection trips classified as \"very high\". It is important to highlight that the local environment of the noisiest parts of the 2 routes had different characteristics. The noisiest sections of the first route were registered in a cycleway located along a wide avenue that follows a river surrounded by green areas, but where the posted speed limit for cars is 60 km/h. There is clearly a conflict here, given that despite the safe circulation conditions provided by the cycleway and the pleasant visual environment found nearby the river, the local noise conditions were not at all favorable to cyclists. In terms of comparison, though, the noisiest section of the other route is even worst. In addition to the high levels of noise exposure, the area is unsafe and not very pleasant to cyclists due to the circulation in mixed traffic conditions. On the other hand, it is conveniently located in terms of accessibility, what shows once more the complexity involved in the process of planning new cycling facilities.
13

Avaliação da exposição de ciclistas ao ruído em uma cidade média brasileira / Assessment of cyclists\' exposure to noise in a Brazilian medium-sized city

Ramos, Thiago da Cunha 17 March 2017 (has links)
Embora muitas cidades brasileiras estejam gradualmente implementando infraestruturas cicloviárias, a exposição dos ciclistas ao ruído ainda não é vista como um elemento a ser considerado no processo de planejamento. A partir deste pressuposto, o objetivo deste estudo é avaliar a exposição dos ciclistas ao ruído em São Carlos, SP, cidade média brasileira na qual cerca de 244 mil habitantes, 107 mil carros e 25 mil motocicletas foram contados em 2016. O estudo envolveu os seguintes procedimentos: i) definições preliminares e ajustes relativos às campanhas de coleta de dados, ii) coleta de dados, iii) validação de dados, iv) cálculo de níveis de exposição ao ruído e v) avaliação da exposição dos ciclistas ao ruído. Foram analisadas duas rotas. A primeira apresentava infraestrutura cicloviária (ciclovias ou ciclofaixas), em alguns dos 12 setores considerados para análise. A segunda rota foi dividida em dois setores, ambos sem infraestrutura cicloviária, mas com um excelente potencial para atrair viagens de bicicleta devido à localização privilegiada da área na cidade. A exposição ao ruído foi classificada de acordo com a percentagem média de valores de SEL (Sound Exposure Level) acima de 85 dBA e de acordo com valores de Lnp (Nível de Poluição Sonora). De maneira geral, os níveis de exposição dos ciclistas ao ruído foram classificados como \"muito alto\" ou \"alto\" em todas as 14 subdivisões das duas rotas, três das quais foram classificados como insalubres. Além disso, mesmo as seções com os menores valores de Lnp apresentaram quase metade das viagens para coleta de dados classificadas como \"muito altas\". É importante destacar que os locais, das partes mais ruidosas das duas rotas, tinham características distintas. Os trechos mais ruidosos da primeira rota foram registrados em uma ciclovia localizada ao longo de uma avenida larga, que margeia um rio e é cercada por áreas verdes, mas onde o limite de velocidade para carros é de 60 km/h. Há claramente um conflito aqui, dado que, apesar das condições de circulação seguras proporcionadas pela ciclovia e o agradável ambiente visual encontrado nas proximidades do rio, as condições locais de ruído não eram nada favoráveis aos ciclistas. Em termos de comparação, porém, a seção mais ruidosa da outra rota é ainda pior. Além dos altos níveis de exposição ao ruído, a área é insegura e pouco agradável para os ciclistas devido à circulação em condições de tráfego misto. Por outro lado, é convenientemente localizado em termos de acessibilidade, o que mostra uma vez mais a complexidade envolvida no processo de planejamento de novas infraestruturas cicloviárias. / Although many Brazilian cities are gradually implementing cycling infrastructures, the cyclists\' exposure to noise is not yet seen as an element to be considered in the planning process. With this assumption as a starting point, the objective of this study is to assess cyclists\' exposure to noise in São Carlos, SP, a Brazilian medium-sized city in which around 244,000 inhabitants, 107,000 cars and 25,000 motorcycles were counted in 2016. The study involved the following procedures: i) preliminary definitions and adjustments regarding the data collection campaigns, ii) data collection, iii) data validation, iv) calculation of noise exposure levels, and v) assessment of cyclists\' exposure to noise. Two routes have been analyzed. The first one had dedicated cycling infrastructure, i.e., cycleways and cyclelanes, in some of the 12 sectors considered for analysis. The second route was split in two sectors, both without dedicated cycling infrastructure but with an excellent potential for attracting cycling trips due to the privileged location of the area in the city. Noise exposure was classified according to the average percentage of Sound Exposure Level (SEL) values above 85 dBA and according to the values of noise pollution levels (Lnp). In general, all sections of the two routes were classified as either \"very high\" or \"high\" regarding the cyclists\' exposure to noise, and 3 out of the total 14 sectors were classified as unhealthy. Furthermore, even the sections with the lowest noise exposure levels had nearly half of the data collection trips classified as \"very high\". It is important to highlight that the local environment of the noisiest parts of the 2 routes had different characteristics. The noisiest sections of the first route were registered in a cycleway located along a wide avenue that follows a river surrounded by green areas, but where the posted speed limit for cars is 60 km/h. There is clearly a conflict here, given that despite the safe circulation conditions provided by the cycleway and the pleasant visual environment found nearby the river, the local noise conditions were not at all favorable to cyclists. In terms of comparison, though, the noisiest section of the other route is even worst. In addition to the high levels of noise exposure, the area is unsafe and not very pleasant to cyclists due to the circulation in mixed traffic conditions. On the other hand, it is conveniently located in terms of accessibility, what shows once more the complexity involved in the process of planning new cycling facilities.
14

Machine-human Cooperative Control of Welding Process

Zhang, Weijie 01 January 2014 (has links)
An innovative auxiliary control system is developed to cooperate with an unskilled welder in a manual GTAW in order to obtain a consistent welding performance. In the proposed system, a novel mobile sensing system is developed to non-intrusively monitor a manual GTAW by measuring three-dimensional (3D) weld pool surface. Specifically, a miniature structured-light laser amounted on torch projects a dot matrix pattern on weld pool surface during the process; Reflected by the weld pool surface, the laser pattern is intercepted by and imaged on the helmet glass, and recorded by a compact camera on it. Deformed reflection pattern contains the geometry information of weld pool, thus is utilized to reconstruct its $3$D surface. An innovative image processing algorithm and a reconstruction scheme have been developed for (3D) reconstruction. The real-time spatial relations of the torch and the helmet is formulated during welding. Two miniature wireless inertial measurement units (WIMU) are mounted on the torch and the helmet, respectively, to detect their rotation rates and accelerations. A quaternion based unscented Kalman filter (UKF) has been designed to estimate the helmet/torch orientations based on the data from the WIMUs. The distance between the torch and the helmet is measured using an extra structure-light low power laser pattern. Furthermore, human welder's behavior in welding performance has been studied, e.g., a welder`s adjustments on welding current were modeled as response to characteristic parameters of the three-dimensional weld pool surface. This response model as a controller is implemented both automatic and manual gas tungsten arc welding process to maintain a consistent full penetration.
15

Uma Abordagem para Sensoriamento Urbano Preliminar Usando Coletores de Dados

Resende, Ítalo Raphael Amador 23 September 2016 (has links)
Submitted by Fernando Souza (fernandoafsou@gmail.com) on 2017-08-15T14:38:05Z No. of bitstreams: 1 arquivototal.pdf: 1777278 bytes, checksum: 2196e7f609f737e29db2451204418d72 (MD5) / Made available in DSpace on 2017-08-15T14:38:05Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1777278 bytes, checksum: 2196e7f609f737e29db2451204418d72 (MD5) Previous issue date: 2016-09-23 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This study suggests the use of a approach to initial urban sensing, in the context of intelligent cities, by data collectors. The approaches currently used for the instrumentation of the cities are usually based on fixed sensors and present challenges relating to power-up, security, maintenance and communication of the sensors, resulting on the increase of the project’s cost. In order to decrease the complexity and costs observed in current models, we propose the use of existing mobility agents (such as metropolitan buses, for example) to provide mobility to traditional sensors. We believe this strategy can help overcome some of the existing challenges and allow a preliminary sensing of the cities in a more affordably way. To evaluate the feasibility of the proposed approach, a series of experiments were conducted using climate microstations positioned statically and also in motion. One of the evaluation fronts was to compare the change in average physical quantities obtained through frequent readings versus more sporadic readings that were collected by stationary sensors. Then the results obtained were compared with samples collected in a mobile way with the use of mobile agents equipped with sensors acting as urban data collectors. The results indicate that the approach is very promising and may be used in combination with conventional approaches, such as the initial detection of heat islands, pollution or traffic jam which can subsequently be monitored with equipments of greater precision. / Este estudo sugere o uso de uma abordagem para o sensoriamento urbano preliminar, no contexto de cidades inteligentes, através do uso de coletores de dados. As abordagens atualmente utilizadas para a instrumentação das cidades normalmente se baseiam em sensores fixos e apresentam desafios referentes à energização, segurança, manutenção e comunicação dos sensores, resultando em aumento de custo dos projetos. Visando à diminuição da complexidade e dos custos observados nos modelos atuais, propomos a utilização de agentes de mobilidade já existentes (como ônibus metropolitanos, por exemplo) para proporcionar mobilidade a sensores tradicionais. Acreditamos que esta estratégia possa ajudar a superar alguns dos obstáculos existentes e permitir um sensoriamento preliminar das cidades de forma mais acessível. Para avaliar a viabilidade da abordagem proposta, uma série de experimentos foi conduzida utilizando-se microestações meteorológicas posicionadas de forma estática e também em movimento. Uma das frentes de avaliação foi comparar a variação das médias de grandezas físicas obtidas através de leituras frequentes versus leituras mais esporádicas, coletadas por sensores estacionários. Em seguida, os resultados obtidos foram comparados com amostras coletadas de forma móvel com a utilização de agentes de mobilidade equipados com sensores e atuando como coletores de dados urbanos. Os resultados apontam que a abordagem é bastante promissora e pode ser usada de forma combinada com estratégias tradicionais, como por exemplo na detecção inicial de ilhas de calor, poluição ou congestionamentos que podem ser, posteriormente, monitoradas com equipamentos de maior precisão.
16

User-Centric Privacy Preservation in Mobile and Location-Aware Applications

Guo, Mingming 10 April 2018 (has links)
The mobile and wireless community has brought a significant growth of location-aware devices including smart phones, connected vehicles and IoT devices. The combination of location-aware sensing, data processing and wireless communication in these devices leads to the rapid development of mobile and location-aware applications. Meanwhile, user privacy is becoming an indispensable concern. These mobile and location-aware applications, which collect data from mobile sensors carried by users or vehicles, return valuable data collection services (e.g., health condition monitoring, traffic monitoring, and natural disaster forecasting) in real time. The sequential spatial-temporal data queries sent by users provide their location trajectory information. The location trajectory information not only contains users’ movement patterns, but also reveals sensitive attributes such as users’ personal habits, preferences, as well as home and work addresses. By exploring this type of information, the attackers can extract and sell user profile data, decrease subscribed data services, and even jeopardize personal safety. This research spans from the realization that user privacy is lost along with the popular usage of emerging location-aware applications. The outcome seeks to relive user location and trajectory privacy problems. First, we develop a pseudonym-based anonymity zone generation scheme against a strong adversary model in continuous location-based services. Based on a geometric transformation algorithm, this scheme generates distributed anonymity zones with personalized privacy parameters to conceal users’ real location trajectories. Second, based on the historical query data analysis, we introduce a query-feature-based probabilistic inference attack, and propose query-aware randomized algorithms to preserve user privacy by distorting the probabilistic inference conducted by attackers. Finally, we develop a privacy-aware mobile sensing mechanism to help vehicular users reduce the number of queries to be sent to the adversarial servers. In this mechanism, mobile vehicular users can selectively query nearby nodes in a peer-to-peer way for privacy protection in vehicular networks.
17

安卓智慧型手機上可設定式之行為感測記錄器 / A Configurable Activity Logger for Android Smartphones

王俊翔, Wang ,Chun Hsiang Unknown Date (has links)
近年來隨著智慧型手機的興起,人們開始利用智慧型手機處理日常生活事務及社群娛樂。無形中,已逐漸的改變日常行為模式。因此,許多學者也開始進行人們使用智慧型手機狀況的研究。 若透過傳統問卷等方式蒐集分析使用記錄,受訪者可能因訪問員的外在因素而影響問卷有效性。為解決此問題,很多研究開始在智慧型手機中安裝應用程式,蒐集使用記錄,藉以分析使用行為。然現今此類應用程式,都是為特定的研究進行開發,缺乏了彈性的考量。因此,本論文設計一個是用於安卓智慧型手機的可客製化行為感測記錄器,提供研究學者依各自需需求產生實驗項目規格檔,由受測者下載至手機,透過我們的行為感測記錄器,記錄平時手機操作行為之相關記錄,並於指定之時機下將記錄上傳供研究學者統計分析,以符合個別實驗之要求。 本研究重點在於如何定義彈性且多樣化的實驗設定檔,並考量載記錄感測過程中,電力大量消耗和受測者隱私資保護的議題,提出因應的解決方法。我們設計與執行幾個實驗來驗證此行為感測記錄器,初步看來,此記錄器可以滿足我們的主要需求,但結果也導引出一些需改進的設計議題。 / In recent years, with the rise of smart phones, the public began to take advantage of smart phones in daily life and social engagements. Virtually, smart phones have gradually changed people's behavior patterns so that researchers are eager to understand the how people use smartphones in their daily life. In this thesis, we present a configurable activity logger for Android smartphones for recording a smartphone’s sensor data and the user’s operations. Instead of one Android App for each researcher’s experiment, our approach is to devise a general logger App that can be customized to collect different data items according to the needs of various researchers. Specifically, our logger App accepts experiment configuration files in which researchers specify what data items to collect and at what frequency, and then conduct the logging task accordingly for each experiment. In other words, our logger works like an interpreter on such experiment configure files. Besides customizability of logging items, our logger concerns the saving of electricity and the preservation of user privacy. Firstly, we have applied various power saving tips published in the literature to the design of our logger. Secondly, we have refrained from collecting any contents that may reveal the user’s identify or that may invade user’s privacy. To evaluate our logger, we have designed and implemented a few data collection experiments. The preliminary results show that our logger can fulfill most of the requirements we set up, though thy also reveal some improvements we need to work on in the future.
18

Crowdsensing solutions for urban pollution monitoring using smartphones

Zamora Mero, Willian Jesús 14 January 2019 (has links)
La contaminación ambiental es uno de los principales problemas que afecta a nuestro planeta. El crecimiento industrial y los aglomerados urbanos, entre otros, están contribuyendo a que dicho problema se diversifique y se cronifique. La presencia de contaminantes ambientales en niveles elevados afecta la salud humana, siendo la calidad del aire y los niveles de ruido ejemplos de factores que pueden causar efectos negativos en las personas tanto psicológicamente como fisiológicamente. Sin embargo, la ubiquidad de los microcomputadores, y el aumento de los sensores incorporados en nuestros smartphones, han hecho posible la aparición de nuevas estrategias para medir dicha contaminación. Así, el Mobile Crowdsensing se ha convertido en un nuevo paradigma mediante el cual los teléfonos inteligentes emergen como tecnología habilitadora, y cuya adopción generalizada proporciona un enorme potencial para su crecimiento, permitiendo operar a gran escala, y con unos costes asumibles para la sociedad. A través del crowdsensing, los teléfonos inteligentes pueden convertirse en unidades de detección flexibles y multiuso que, a través de los sensores integrados en dichos dispositivos, o combinados con nuevos sensores, permiten monitorizar regiones de interés con una buena granularidad tanto espacial como temporal. En esta tesis nos centramos en el diseño de soluciones de crowdsensing usando smartphones donde abordamos problemas de contaminación ambiental, específicamente del ruido y de la contaminación del aire. Con este objetivo, se estudian, en primer lugar, las propuestas de crowdsensing que han surgido en los últimos años. Los resultados de nuestro estudio demuestran que todavía hay mucha heterogeneidad en términos de tecnologías utilizadas y métodos de implementación, aunque los diseños modulares en el cliente y en el servidor parecen ser dominantes. Con respecto a la contaminación del aire, proponemos una arquitectura que permita medir la contaminación del aire, concretamente del ozono, dentro de entornos urbanos. Nuestra propuesta utiliza smartphones como centro de la arquitectura, siendo estos dispositivos los encargados de leer los datos de un sensor móvil externo, y de luego enviar dichos datos a un servidor central para su procesamiento y tratamiento. Los resultados obtenidos demuestran que la orientación del sensor y el período de muestreo, dentro de ciertos límites, tienen muy poca influencia en los datos capturados. Con respecto a la contaminación acústica, proponemos una arquitectura para medir los niveles de ruido en entornos urbanos basada en crowdsensing, y cuya característica principal es que no requiere intervención del usuario. En esta tesis detallamos aspectos tales como la calibración de los smartphones, la calidad de las medidas obtenidas, el instante de muestreo, el diseño del servidor, y la interacción cliente-servidor. Además, hemos validado nuestra solución en escenarios reales para demostrar el potencial de la solución alcanzada. Los resultados experimentales muestran que, con nuestra propuesta, es posible medir niveles de ruido en diferentes zonas urbanas o rurales con un grado de precisión comparable al de los dispositivos profesionales, todo ello sin requerir intervención del usuario, y con un consumo reducido en cuanto a recursos del sistema. En general, las diferentes contribuciones de esta tesis doctoral ofrecen un punto de partida para nuevos desarrollos, ofreciendo estrategias de calibración y algoritmos eficientes de cara a realizar medidas representativas. Además, una importante ventaja de nuestra propuesta es que puede ser implementada de forma directa tanto en instituciones públicas como no gubernamentales en poco tiempo, ya que utiliza tecnología accesible y soluciones basadas en código abierto. / La contaminació ambiental és un dels principals problemes que afecten el nostre planeta. El creixement industrial i els aglomerats urbans, entre altres, estan contribuint al fet que aquest problema es diversifique i es cronifique. La presència de contaminants ambientals en nivells elevats afecta la salut humana, sent la qualitat de l'aire i els nivells de soroll exemples de factors que poden causar efectes negatius en les persones, tant psicològicament com fisiològicament. No obstant això, la ubiqüitat de les microcomputadores i l'augment dels sensors incorporats als nostres telèfons intel·ligents han fet possible l'aparició de noves estratègies per a mesurar aquesta contaminació. Així, el mobile crowdsensing s'ha convertit en un nou paradigma mitjançant el qual els telèfons intel·ligents emergeixen com a tecnologia habilitadora, i l'adopció generalitzada d'aquest proporciona un enorme potencial per al seu creixement, ja que permet operar a gran escala i amb uns costos assumibles per a la societat. A través del crowdsensing, els telèfons intel·ligents poden convertir-se en unitats de detecció flexibles i multiús que, a través dels sensors integrats en els esmentats dispositius, o combinats amb nous sensors, permeten monitoritzar regions d'interès amb una bona granularitat, tant espacial com temporal. En aquesta tesi ens centrem en el disseny de solucions de crowdsensing usant telèfons intel·ligents, on abordem problemes de contaminació ambiental, específicament del soroll i de la contaminació de l'aire. Amb aquest objectiu, s'estudien, en primer lloc, les propostes de crowdsensing que han sorgit en els últims anys. Els resultats del nostre estudi demostren que encara hi ha molta heterogeneïtat en termes de tecnologies utilitzades i mètodes d'implementació, encara que els dissenys modulars en el client i en el servidor semblen ser dominants. Pel que fa a la contaminació de l'aire, proposem una arquitectura que permeta mesurar la contaminació d'aquest, concretament de l'ozó, dins d'entorns urbans. La nostra proposta utilitza telèfons intel·ligents com a centre de l'arquitectura, sent aquests dispositius els encarregats de llegir les dades d'un sensor mòbil extern, i d'enviar després aquestes dades a un servidor central per al seu processament i tractament. Els resultats obtinguts demostren que l'orientació del sensor i el període de mostratge, dins de certs límits, tenen molt poca influència en les dades capturades. Pel que fa a la contaminació acústica, proposem una arquitectura per a mesurar els nivells de soroll en entorns urbans basada en crowdsensing, i la característica principal de la qual és que no requereix intervenció de la persona usuària. En aquesta tesi detallem aspectes com ara el calibratge dels telèfons intel·ligents, la qualitat de les mesures obtingudes, l'instant de mostratge, el disseny del servidor i la interacció client-servidor. A més, hem validat la nostra solució en escenaris reals per a demostrar el potencial de la solució assolida. Els resultats experimentals mostren que, amb la nostra proposta, és possible mesurar nivells de soroll en diferents zones urbanes o rurals amb un grau de precisió comparable al dels dispositius professionals, tot això sense requerir intervenció de l'usuari o usuària, i amb un consum reduït quant a recursos del sistema. En general, les diferents contribucions d'aquesta tesi doctoral ofereixen un punt de partida per a nous desenvolupaments, i ofereixen estratègies de calibratge i algorismes eficients amb vista a realitzar mesures representatives. A més, un important avantatge de la nostra proposta és que pot ser implementada de forma directa tant en institucions públiques com no governamentals en poc de temps, ja que utilitza tecnologia accessible i solucions basades en el codi obert. / Environmental pollution is one of the main problems that affect our planet. Industrial growth and urban agglomerations, among others, are contributing to the diversification and chronification of this problem. The presence of environmental pollutants at high levels affect human health, with air quality and noise levels being examples of factors that can cause negative effects on people both psychologically and physiologically. Traditionally, environmental pollution is measured through monitoring centers, which are usually fixed and have a high cost. However, the ubiquity of microcomputers and the increase in the number of sensors embedded in our smartphones, have paved the way for the appearance of new strategies to measure such pollution. Thus, Mobile Crowdsensing has become a new paradigm through which smartphones emerge as an enabling technology, and whose widespread adoption provides enormous potential for growth, allowing large-scale operations, and with costs acceptable to our society. Through crowdsensing, smartphones can become flexible and multipurpose detection units that, through the sensors integrated into these devices, or combined with new sensors, allow monitoring regions of interest with good spatial and temporal granularity. In this thesis, we focus on the design of crowdsensing solutions using smartphones. We deal with environmental pollution problems, specifically noise and air pollution. With this objective, the crowdsensing proposals that have emerged in recent years are studied in the first place. The results of our study show that there is still a lot of heterogeneity in terms of technologies used and implementation methods, although modular designs at both client and server seem to be dominant. Concerning air pollution, we propose an architecture that allows measuring air pollution, specifically ozone, in urban environments. Our proposal uses smartphones as the center of the architecture, being these devices responsible for reading the data obtained by an external mobile sensor, and then sending such data to a central server for processing and analysis. In this proposal, several problems have been analyzed with regard to the orientation of the external sensor and the sampling time, and the proposed solution has been validated in real scenarios. The results obtained show that the orientation of the sensor and the sampling period, within certain limits, have very little influence on the captured data. Also, by comparing the heat maps generated by our solution with the data from the existing monitoring stations in the city of Valencia, we demonstrate that our approach is capable of providing greater data granularity. Concerning noise pollution, we propose an architecture to measure noise levels in urban environments based on crowdsensing, and whose main characteristic is that it does not require user intervention. In this thesis, we detail aspects such as the calibration of smartphones, the quality of the measurements obtained, the sampling instant, the server design, and the client-server interaction. Besides, we have validated our solution in real scenarios to demonstrate the potential of the proposed solution. Experimental results show that, with our proposal, it is possible to measure noise levels in different urban or rural areas with a degree of precision comparable to that of professional devices, all without requiring the intervention of the user, and with reduced consumption of system resources. In general, the different contributions of this doctoral thesis provide a starting point for new developments, offering efficient calibration strategies and algorithms to make representative measurements. Besides, a significant advantage of our proposal is that it can be implemented straightforwardly by both public and non-governmental institutions in a short time, as it relies on accessible technology and open source software / Zamora Mero, WJ. (2018). Crowdsensing solutions for urban pollution monitoring using smartphones [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/115483 / TESIS
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[en] USING BODY SENSOR NETWORKS AND HUMAN ACTIVITY RECOGNITION CLASSIFIERS TO ENHANCE THE ASSESSMENT OF FORM AND EXECUTION QUALITY IN FUNCTIONAL TRAINING / [pt] UTILIZANDO REDES DE SENSORES CORPORAIS E CLASSIFICADORES DE RECONHECIMENTO DE ATIVIDADE HUMANA PARA APRIMORAR A AVALIAÇÃO DE QUALIDADE DE FORMA E EXECUÇÃO EM TREINAMENTOS FUNCIONAIS

RAFAEL DE PINHO ANDRE 14 December 2020 (has links)
[pt] Dores no pé e joelho estão relacionadas com patologias ortopédicas e lesões nos membros inferiores. Desde a corrida de rua até o treinamento funcional CrossFit, estas dores e lesões estão correlacionadas com a distribuição iregular da pressão plantar e o posicionamento inadequado do joelho durante a prática física de longo prazo, e podem levar a lesões ortopédicas graves se o padrão de movimento não for corrigido. Portanto, o monitoramento da distribuição da pressão plantar do pé e das características espaciais e temporais das irregularidades no posicionamento dos pés e joelhos são de extrema importância para a prevenção de lesões. Este trabalho propõe uma plataforma, composta de uma rede de sensores vestíveis e um classificador de Reconhecimento de Atividade Humana (HAR), para fornecer feedback em tempo real de exercícios funcionais, visando auxiliar educadores físicos a reduzir a probabilidade de lesões durante o treinamento. Realizamos um experimento com 12 voluntários diversos para construir um classificador HAR com aproximadamente de 87 porcento de precisão geral na classificação, e um segundo experimento para validar nosso modelo de avaliação física. Por fim, realizamos uma entrevista semi estruturada para avaliar questões de usabilidade e experiência do usuário da plataforma proposta.Visando uma pesquisa replicável, fornecemos informações completas sobre o hardware e o código fonte do sistema, e disponibilizamos o conjunto de dados do experimento. / [en] Foot and knee pain fave been associated with numerous orthopedic pathologies and injuries of the lower limbs. From street running to CrossFitTM functional training, these common pains and injuries correlate highly with unevenly distributed plantar pressure and knee positioning during long-term physical practice and can lead to severe orthopedic injuries if the movement pattern is not amended. Therefore, the monitoring of foot plantar pressure distribution and the spatial and temporal characteristics of foot and knee positioning abnomalities is of utmost importance for injury prevention. This work proposes a platform, composed af an lot wearable body sensor network and a Human Activity Recognition (HAR), to provide realtime feedback of functional exercises, aiming to enhace physical educators capability to mitigate the probability of injuries during training. We conducted an experiment with 12 diverse volunteers to build a HAR classifier that achieved about 87 percent overall classification accuracy, and a second experiment to validate our physical evaluation model. Finally, we performed a semi-structured interview to evaluate usability and user experience issues regarding the proposed platform. Aiming at a replicable research, we provide full hardware information, system source code and a public domain dataset.

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