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Avaliação de arquitetura paralela para smartphones e tablets utilizando GNU/Linux e MPI para processamento de dados / Evaluation of paralle architecture for smartphones and tablets using GNU/Linux and MPI for data processingZanoni, Felipe Sanches 06 September 2013 (has links)
A versatilidade e principalmente o poder de processamento dos atuais celulares, mais conhecidos como smartphones, e também dos tablets, impulsionam a computação de algorítimos complexos nesses dispositivos. Cada celular ou tablet pode fazer parte de uma grande rede de computadores com capacidade para processar uma enorme quantidade de dados com um consumo muito baixo de energia se comparado aos computadores convencionais. Um outro grande motivador é que muitos desses celulares possuem o sistema operacional Android, o qual é baseado no núcleo Linux. Isso facilita a migração de projetos já desenvolvidos em computadores para essa nova plataforma móvel, uma vez que é possível executar um sistema operacional completo GNU/Linux nesses dispositivos. O objetivo desse trabalho é avaliar e comparar o desempenho de um cluster híbrido formado por dispositivos móveis e computadores, mostrando que é possível desenvolver aplicativos utilizando MPI para processamento paralelo em celulares da mesma forma com que se desenvolve aplicativos para computadores em GNU/Linux. Os resultados mostram qual é a diferença de poder computacional entre os computadores de arquitetura x86 e os dispositivos móveis de tecnologia ARM. / Versatility and mainly processing power of nowadays smartphones and tablets boost complex algorithms computation on these devices. Each cellphone or tablet can be part of a big computer network capable of processing a huge amount of data with low power consumption compared to personal computers. A great motivator also is that these devices have the Android operational system that is based on Linux kernel, what facilitates developed projects to migrate easily to this new platform. The goal of this project is to evaluate and compare a hybrid cluster performance formed by mobile devices and computers, showing that is possible to develop software using MPI for parallel processing over smartphones and tablets the same way as for GNU/Linux computers. The results show what is the processing power difference between x86 architecture computers and mobile devices using ARM architecture.
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Konsumentbeteendet på Mobiltelefonmarknaden : En studie om applikationsanvändandetChabane, Karim, Pärnänen, Christoffer, Viel Lamare, Philippe January 2010 (has links)
Studien är en undersökning om hur olika delar av konsumentbeteendet bland applikationsanvändare ser ut. En applikation är ett program eller en tjänst som tillför en ny funktion i mobiltelefonen. Studiens syfte och problemformulering hur olika delar av konsumentbeteendet ser ut och utifrån det ta fram den typiske applikationsanvändaren. Som teoretisk referensram används en bearbetad version av Peter & Olsons (2008) Wheel of consumer analysis som vi kallar konsumenthjulet. Konsumenthjulet består av affekt och kognition, konsumenters omgivning och beteende. Dessa områden för att få en övergripande bild över konsumentbeteendet. En kvantitativ studie genomfördes genom en webbenkät för att samla in nödvändig data för studien. Enkätdistributionen skedde via forum och sociala medier för att få en så stor spridning som möjligt bland respondenter. I Analysen diskuteras resultatet utifrån konsumenthjulet. Det visar sig att engagemang har stor betydelse för hur applikationer används och delarna av konsumenthjulet påverkas av just detta. I slutsatsen diskuterades den typiska applikationsanvändaren fram och kortfattat är det en man i 25 års ålder som är en hög engagemangsanvändare av applikationer. För fortsatta studier rekommenderas studier om hur företag ska marknadsföra applikationer och mer djupingående studier som kan besvara varför applikationsanvändare beter sig som de gör. / This thesis is a study about the consumer behavior on the cellular telephone market regarding the usage of applications that can be downloaded and used on the cellular telephone. An application is a program or a service that contributes new functions to the cellular telephone. The purpose and main question of the thesis is to describe how different theory parts of the Consumer Wheel form the typical application user. The theoretical frame of reference was an adapted form of Peter & Olsons (2008) Wheel of consumer analysis, a theory framework used to describe the consumer behavior. The Consumer Wheel consist of three parts; affect and cognition, consumer environment and behavior. A quantitative study was carried out through a web-based survey to collect the necessary data for the thesis. The survey was distributed through internet forums and social networks to get as large spread of the survey as possible. In the analyze part of the thesis the result is discussed with the Consumer Wheel. Involvement seem to have a large meaning on how applications are used and that the different parts of the Consumer Wheel are influenced by the level of involvement. In the conclusion part the typical application user is presented as a 25 year old male and he is a high involvement application user. Future studies should focus on how companies can market applications and studies on why application users behave as they do.
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Conceptual design and implementation of tutorials for app development in the context of the lecture 'Mobile Cartography' / Konzeption und Umsetzung von Übungen zur App-Entwicklung im Rahmen der Lehrveranstaltung "Mobile Cartography"Hartl, Maximilian 25 September 2012 (has links) (PDF)
Mobile applications are becoming more and more important in the daily life and offer interesting and completely new aspects to the field of cartography. The technological possibilities provided by computer science have had a large impact on cartography and therefore cartographers must be familiar with the development of software to present geographic information and make it accessible. With the recent rise of mobile devices like smartphones, it is inevitable that this has to include mobile platforms as well.
The main focus of this Bachelor thesis is on the conceptual design and implementation of tutorials to teach the development of mobile applications or 'apps' for the Android platform. The tutorials are going to be part of exercises in a practical course that accompanies the lecture 'Mobile Cartography' held at the Institute of Cartography at the Dresden University of Technology. Five exercises have been created covering key aspects of Android programming with Java. The theoretical part of this thesis starts with providing definitions of important terms of mobile computing and mobile cartography that will play an important role throughout the thesis. After that possibilities of interaction with mobile and web applications are introduced and discussed briefly.
Location-based services and their usage in the context of social networks are discussed in the following section before the sensors of mobile devices are analyzed. A brief discussion of the potential for augmented reality applications is also given. The following second section deals with mobile software platforms and focuses on the Android operating system for mobile devices. Within this section, the features of the Android framework are described and some specific characteristics of software development are explained. The third section is all about the conceptual design and implementation of the tutorials. Considering the requirements for the practical course and different aspects of learning, the pedagogical approach is described. Additionally the ECLASS model which has evolved in the context of E-Learning is explained as it provided the structure of the exercises.
After that, the content of the five exercises which include basics, layout, internal interaction of components, database access and the integration of maps is reflected. Finally, a brief outlook on further possible exercises is given.
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An Evaluation of Smartphone Resources Used by Web AdvertisementsAlbasir, Abdurhman 11 December 2013 (has links)
With the rapid advancement of mobile devices, people have become more attached to them than ever. This rapid growth combined with millions of applications (apps) make smartphones a favourite means of communication among users. In general, the available contents on smartphones, apps and the web, come into two versions: (i) free contents that are monetized via advertisements (ads), and (ii) paid ones that are monetized by user subscription fees. However, the resources (energy, bandwidth, processing power) on-board are limited, and the existence of ads in either websites or free apps can adversely impact these resources. These issues brought the need for good understanding of the mobile advertising eco-system and how such limited resources can be efficiently used.
This thesis focuses on mobile web browsing. Surfing web-pages on smatphones is one of the most commonly used task among smartphone users. However, web-page complexity is increasing, especially when designed for desktop computers. On one hand, the existence of ads in web-pages is essential for publishers' monetization strategy. On the other hand, their existence in webpages leads to even higher complexity of the webpages. This complexity in the smartphone environment, where the battery and bandwidth resources are limited, is reflected in longer loading time, more energy consumed, and more bytes transferred. With this view, quantifying the energy consumption due to web ads in smartphones is essential for publishers to optimize their webpages, and for system designers to develop an energy-aware applications (browsers) and protocols. Apart from their energy impact, ads consume network bandwidth as well. Therefore, quantifying the bandwidth consumption due to downloading web ads is crucial to creating more energy and bandwidth aware applications. This thesis first classifies web content into: (i) core information, and (ii) forced ``unwanted" information, namely ads. Then, describes an approach that enables the separation of web content in a number of a websites. Having done so, the energy cost due to downloading, rendering, and displaying web ads over Wi-Fi and 3G networks is evaluated. That is, how much energy web ads contribute to the total consumed energy when a user accesses the web. Furthermore, the bandwidth consumed by web ads in a number of well-known websites is also evaluated.
Motivated by our findings about ads' impact on the energy and bandwidth, the thesis proposes and implements a novel web-browsing technique that adapts the webpages delivered to smartphones, based on a smartphone's current battery level and the network type. Webpages are adapted by controlling the amount of ads to be displayed. Validation tests confirm that the system, in some cases, can extend smartphone battery life by up to ~ 30\% and save wireless bandwidth up to ~ 44\%.
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Att fånga entreprenörskapets dimensionerUemura, Philip, Abdulamir, Hayder January 2014 (has links)
Syftet med studien är att bidra med kunskap om hur entreprenöriell orientering kan mäta entreprenörskap inom branschen för mobiltelefoni. Förhållandet mellan entreprenörskap och ekonomiska utfall mäts med utgångspunkt i Millers resonemang om entreprenöriell orientering. Hur kan entreprenörskap operationaliseras? Hur ser förhållandet ut mellan entreprenörskap och ekonomiska utfall? Studien baseras på tidigare forskning, facklitteratur, vetenskapliga artiklar, årsredovisningar, branschartiklar, avhandlingar och andra relevanta underlag som belyser entreprenörskap. Både kvalitativ och kvantitativ metod tillämpas för att åstadkomma triangulering. Entreprenörskap kan mätas utifrån hur pass radikal innovationen är. Den nya och tidigare okända innovationen kan resultera i positiva ekonomiska utfall som också mäter graden av entreprenörskap. Entreprenörskap kan mätas genom grad av riskaversion. Risktagande kan ge både positivt och negativt ekonomiskt utfall. Entreprenörskap kan mätas genom proaktivitet och begreppet first mover. Proaktivitet kan bidra till högre grad av entreprenörskap som i sin tur kan ge positiva ekonomiska utfall. Att vara proaktiv idag utgör ingen garanti för positiva ekonomiska utfall i framtiden. / The purpose of this study is to contribute with knowledge concerning how entrepreneurial orientation can measure entrepreneurship within the cellphone business. The relationship between entrepreneurship and economic outcomes is measured using Millers arguments about entrepreneurial orientation. How can entrepreneurship be operationalized? How does the relationship between entrepreneurship and economic outcomes look like? The study is based on prior research, nonfictional literature, scientific articles, annual reports, business articles, theses and other relevant sources, which highlight entrepreneurship. Both qualitative and quantitative method is used to achieve triangulation. Entrepreneurship can be measured by how radical the innovation is. The new and earlier unknown innovation can result in positive economic outcomes, which can be used as a tool for measuring entrepreneurship as well. The level of risk aversion can measure entrepreneurship. Risk taking can result in both positive and negative economic outcomes. Proactiveness can be measured by using the term first mover. Proactiveness can contribute to higher level of entrepreneurship causing positive economic outcomes. Being proactive today does not guarantee positive economic outcomes in the future.
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Alternatives to smartphone applications for real-time information and technology usage among transit ridersWindmiller, Sarah M. 13 January 2014 (has links)
Real-time information that informs transit riders about transit schedules, next bus or train arrivals, and service alerts, is becoming increasingly available, particularly through internet-enabled smartphone applications. However, the extent of communication technology usage amongst transit riders, specifically their access to mobile applications and alternative technologies that can provide real-time information, is largely unknown. Without this information, transit agencies are risking investing in an alternative technology that may not sufficiently supply real-time information to as many as possible riders. The purpose of this study is to identify the differences in individual technology accessibility and prioritize investing in real-time information application development that mirrors the unique characteristics of transit riders. This recognition and development will allow a wider availability of real-time information amongst transit riders. Paired with an investigation of cellular phone usage among transit riders and the general American population, an analysis of Saint Louis Metro’s Onboard Survey was performed. Cross tabulations and chi-squared tests were conducted to examine riders’ communication technology usage. Binary logit models were used to understand how, and whether, the ownership of smartphone applications is dependent on various demographic factors. These analyses identified specific demographic groups that would benefit from supplemental technology methods more conducive to their particular information accessibility. Results showed that communication technology usage has risen substantially in recent years but a portion of riders are still without access to smartphone applications. Specific demographic groups (e.g., riders over 40 years of age) were less likely to own smartphones, and these results indicate that computer-based websites and IVR are the best supplementary alternatives for those groups.
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Use of a Smartphone Application in the Treatment of Depression : The New Wave of Digital Tools in Psychological TreatmentLy, Kien Hoa January 2015 (has links)
Internet-delivered programs based on cognitive behavior therapy (CBT) have during the past decade shown to work in an effective way for the treatment of depression. Due to its accessibility and independence of time and location, smartphone-based CBT might represent the next generation of digital interventions. Depression is an affective disorder that affects as many as 350 million people worldwide. However, with CBT, depression can be treated, but access to this treatment is scarce due to limited health care resources and trained therapists. As a result of this, health care could highly benefit from the use of smartphones for delivering cost-effective treatment that can be made available to a large part of the population who suffer from depression. One treatment that should be especially suitable for the smartphone format is behavioral activation (BA), since it has strong empirical support as well as the benefits of being flexible and rather simple. The overall aim of the thesis was to test and further develop a BA smartphone application, as well as to build a method for how this smartphone application could be used in a comprehensive and effective way in depression treatment. To fulfill this aim, four studies were conducted. The results showed that smartphones have the ability to be used in an effective way in the treatment of depression, including as an add-on to traditional face-to-face sessions. The results also showed that the smartphone format was experienced as a portable and flexible way of accessing the treatment – and thus could be more present in everyday life. In conclusion, there is reason to believe that smartphones will be integrated even further in society and therefore may serve an important role in future mental health care. Since the first indications reveal that depression can be treated by means of a supported smartphone application, it is highly possible that applications for other mental health problems will follow. Furthermore, in this thesis, the same smartphone application has been tested in three different ways and there is potential to apply smartphones in a range of other formats, such as in relapse prevention and as a way to intensify treatment during periods when needed. From a psychiatric research point of view, as my research group has been doing trials on guided internet treatment for more than 15 years, it is now time to move to the next generation of information technology – smartphones. / Internetbaserad kognitiv beteendeterapi (KBT) har under det senaste decenniet visat sig fungera effektivt i behandling av depression. På grund av dess tillgänglighet och flexibilitet i tid och plats har smartphonebaserad KBT potential att bli nästa generation av digitala behandlingar. Depression är en affektiv sjukdom som drabbar så många som 350 miljoner människor världen över. Med hjälp av KBT kan depression behandlas. Dock är tillgången till denna behandling knapp på grund av begränsade resurser i form av utbildade terapeuter. Därmed skulle sjukvården kunna dra stor nytta av användningen av smartphones för att leverera kostnadseffektiv behandling, som kan göras tillgänglig för människor som lider av depression. En behandling som kan vara särskilt lämplig för smartphone-formatet är beteendeaktivering (BA), eftersom den har starkt empiriskt stöd samtidigt som den är flexibel och relativt enkel. Det övergripande syftet med avhandlingen var att testa och vidareutveckla en smartphone-applikation baserad på BA, samt att bygga en behandlingsmetod för denna smartphone-applikation som skulle kunna användas för att effektivt behandla depression. För att uppnå detta syfte genomfördes fyra studier. Resultaten visade att smartphones kan användas på ett effektivt sätt i behandling av depression, bland annat som komplement till traditionella live-sessioner. Resultaten visade också initiala indikationer på att smartphoneformatet upplevdes som ett portabelt och flexibelt sätt att komma åt behandlingen - och därmed blev mer närvarande i vardagen.
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Posicionamento relativo em tempo real e pós-processado utilizando microrreceptor GNSS usado em smartphone / Relative positioning in real-time and post-processed using GNSS micro receiver used in smartphoneOliveira, Gabriel Diniz de 22 July 2014 (has links)
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Previous issue date: 2014-07-22 / Over time has increased the need for low cost positioning of the populatio, and for this reason the demand for navigation devices has grown considerably in all levels of users of these devices, the population in general has greater access to smartphones because of its many features. Smartphones using micro GNSS receiver has a main component of positioning, where the pseudorange is its basic observable. The data sources for GPS corrections are increasingly available to the community through institutions as the IBGE with the Brazilian Network for Continuous Monitoring (RBMC). Thus, there is a greater possibility of improvement in accuracy of positioning these devices with the post- processed relative positioning and even in real time. With these possibilities and needs, this study aims the establishment of methodology that improves the accuracy in the positioning devices using micro GNSS receiver with a recursive least squares estimation with the Kalman gain matrix applied in relative positioning static by double difference of pseudorange in short baselines. To verify the effectiveness of this methodology is used SiRFstar IV micro receiver data which receives data only in L1 frequency GPS constellation. Was used reference RBMC stations to process these data. With tracking 15 minutes in known points had a mean deviation in the horizontal component of the plane coordinates 29 cm for post-processing and 98 cm for the real time processing, and, for the single point positioning average deviation was 6 meters. With this, it was concluded that the use of static methods for processing on recursive least squares estimation improves the accuracy of positioning significantly, where mobile devices that were previously given only to navigation may also be used for mapping. / Com o passar do tempo aumentou a necessidade da população em posicionamento a baixo custo, e por este motivo a procura por aparelhos de navegação tem crescido consideravelmente em todos os níveis de usuários. Destes dispositivos, a população no geral tem maior acesso aos smartphones devido a suas diversas funcionalidades. Os smartphones utilizam de microrreceptor GNSS como principal componente de posicionamento, sendo que sua observável básica é a pseudodistância derivada do código C/A. As fontes de dados para correções GPS estão cada vez mais disponíveis para a comunidade por meio de instituições como o IBGE com a Rede Brasileira de Monitoramento Continuo dos Sistemas GNSS (RBMC). Com isso, tem-se uma maior possibilidade de melhorias na acurácia do posicionamento destes dispositivos com o posicionamento relativo pós-processado e até mesmo em tempo real. Com estas possibilidades e necessidades, este trabalho tem como objetivo o estabelecimento de metodologia que melhore a acurácia no posicionamento de dispositivos móveis que utilizam microrreceptor GNSS, utilizando a estimativa de mínimos quadrados recursiva com a matriz de ganho de Kalman aplicada no posicionamento relativo estático por dupla diferença da pseudodistância em linhas de base curtas. Para verificar a eficácia desta metodologia utilizou-se dados do microrreceptor SiRFstar IV que recebe dados na frequência L1 da constelação GPS. Foram utilizadas as estações de referência da RBMC para o processamento destes dados. Com rastreios de 15 minutos em pontos de coordenadas conhecidas teve-se um desvio médio na componente horizontal das coordenadas planas de 29 centímetros para o pós- processamento e 98 centímetros para o processamento em tempo real, sendo que, para o posicionamento por ponto simples o desvio médio foi de 6 metros. Com isso, concluiu-se que a utilização da metodologia de processamento relativo estático por estimativa dos mínimos quadrados recursiva melhorou a acurácia do posicionamento de forma significativa, onde dispositivos móveis 14que até então eram indicados somente para navegação podem ser utilizados também para mapeamento.
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[en] AN EXPERIMENT ON CONCEPTUAL DESIGN OF PERVASIVE MOBILE GAMES USING QUALITY REQUIREMENTS / [pt] UM EXPERIMENTO NO DESIGN CONCEITUAL DE JOGOS PERVASIVOS MÓVEIS USANDO REQUISITOS DE QUALIDADEFELIPE BALDINO MOREIRA 28 January 2016 (has links)
[pt] Jogos pervasivos móveis são um tipo novo de jogo que mistura
aparelhos móveis (como telefones celulares), mundos virtuais e atividades
que acontecem no mundo real. Nessa àrea recente, a literatura sobre projeto
conceitual e requisitos de qualidade sobre pervasividade são escassas. A
pervasividade é a qualidade (difícil de ser definida objetivamente) que difere
os jogos pervasivos móveis dos jogos digitais tradicionais. Neste trabalho, nós
discutimos o desenvolvimento de um jogo pervasivo móvel usando requisitos
de qualidade relacionados à pervasividade. Nós consideramos esses requisitos
durante todo o processo de desenvolvimento (i.e., as etapas de projeto,
produção e pós-produção), focando na análise, implementação e gameplay.
Nós esperamos que os nossos resultados possam ajudar a melhorar guias de
desenvolvimento relacionadas a jogos pervasivos móveis. / [en] Pervasive games is an emerging game genre that mixes up mobile
devices (such as smartphones), virtual worlds, and gameplay based on the
real world, creating a mixed-reality game. This recent area lacks literature
about conceptual design and quality requirements related to pervasiveness
– the ultimate and elusive quality that differentiate pervasive mobile
games from traditional digital games. In the present work, we discuss the
development of a pervasive mobile game using quality requirements related
to pervasiveness. Also, we consider those requirements in the entire game
project (e.g., design, production, and post-production stages), focusing on
the analysis, implementation, and gameplay. We expect that our results
could help in improving the current state of design guidelines to develop
pervasive mobile games.
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Smartphone-based indoor positioning using Wi-Fi, inertial sensors and Bluetooth / Positionnement intérieur basé sur les smartphones à l'aide de Wi-Fi, des capteurs inertiels et BluetoothTa, Viet-Cuong 15 December 2017 (has links)
Grâce à l’émergence dans la vie quotidienne des appareils de plus en plus populaires que sont les smartphones et les tablettes, la tâche de postionner l'utilisateur par le biais de son téléphone est une problématique fortement étudiée dans les domaines non seulement de la recherche mais également des communautés industrielles. Parmi ces technologies, les approches GPS sont devenues une norme et ont beaucoup de succès pour une localisation en environnement extérieur. Par contre, le Wi-Fi, les capteurs inertiels et le Bluetooth sont plutôt préférés pour les tâches de positionnement dans un environnement intérieur.Pour ce qui concerne le positionnement des smartphones, les approches basées sur les « empreintes digitales » (fingerprint) Wi-Fi sont bien établies. D'une manière générale, ces approches tentent d'apprendre la fonction de correspondance (cartographie) des caractéristiques du signal Wi-Fi par rapport à la position de l’appareil dans le monde réel. Elles nécessitent généralement une grande quantité de données pour obtenir une bonne cartographie. Lorsque ces données d'entraînement disponibles sont limitées, l'approche basée sur les empreintes digitales montre alors des taux d’erreurs élevés et devient moins stable. Dans nos travaux, nous explorons d’autres approches, différentes, pour faire face à cette problématique du manque de données d'entraînement. Toutes ces méthodes sont testées sur un ensemble de données public qui est utilisé lors d’une compétition internationale à la Conférence IPIN 2016.En plus du système de positionnement basé sur la technologie Wi-Fi, les capteurs inertiels du smartphone sont également utiles pour la tâche de suivi. Les trois types de capteurs, qui sont les accéléromètres, le gyroscope et la boussole magnétique, peuvent être utilisés pour suivre l'étape et la direction de l'utilisateur (méthode SHS). Le nombre d'étapes et la distance de déplacement de l'utilisateur sont calculés en utilisant les données de l'accéléromètre. La position de l'utilisateur est calculée par trois types de données avec trois méthodes comprenant la matrice de rotation, le filtre complémentaire et le filtre de Madgwick. Il est raisonnable de combiner les sorties SHS avec les sorties de Wi-Fi, car les deux technologies sont présentes dans les smartphones et se complètent. Deux approches combinées sont testées. La première approche consiste à utiliser directement les sorties Wi-Fi comme points de pivot pour la fixation de la partie de suivi SHS. Dans la deuxième approche, nous comptons sur le signal Wi-Fi pour construire un modèle d'observation, qui est ensuite intégré à l'étape d'approximation du filtre à particules. Ces combinaisons montrent une amélioration significative par rapport au suivi SHS ou au suivi Wi-Fi uniquement.Dans un contexte multiutilisateur, la technologie Bluetooth du smartphone pourrait fournir une distance approximative entre les utilisateurs. La distance relative est calculée à partir du processus de numérisation du périphérique Bluetooth. Elle est ensuite utilisée pour améliorer la sortie des modèles de positionnement Wi-Fi. Nous étudions deux méthodes. La première vise à créer une fonction d'erreur qui permet de modéliser le bruit dans la sortie Wi-Fi et la distance approximative produite par le Bluetooth pour chaque intervalle de temps spécifié. La seconde méthode considère par contre cette relation temporelle et la contrainte de mouvement lorsque l'utilisateur se déplace. Le modèle d'observation du filtre à particules est une combinaison entre les données Wi-Fi et les données Bluetooth. Les deux approches sont testées en fonction de données réelles, qui incluent jusqu'à quatre utilisateurs différents qui se déplacent dans un bureau. Alors que la première approche n'est applicable que dans certains scénarios spécifiques, la deuxième approche montre une amélioration significative par rapport aux résultats de position basés uniquement sur le modèle d'empreintes digitales Wi-Fi. / With the popularity of smartphones and tablets in daily life, the task of finding user’s position through their phone gains much attention from both the research and industry communities. Technologies integrated in smartphones such as GPS, Wi-Fi, Bluetooth and camera are all capable for building a positioning system. Among those technologies, GPS has approaches have become a standard and achieved much success for the outdoor environment. Meanwhile, Wi-Fi, inertial sensors and Bluetooth are more preferred for positioning task in indoor environment.For smartphone positioning, Wi-Fi fingerprinting based approaches are well established within the field. Generally speaking, the approaches attempt to learn the mapping function from Wi-Fi signal characteristics to the real world position. They usually require a good amount of data for finding a good mapping. When the available training data is limited, the fingerprinting-based approach has high errors and becomes less stable. In our works, we want to explore different approaches of Wi-Fi fingerprinting methods for dealing with a lacking in training data. Based on the performance of the individual approaches, several ensemble strategies are proposed to improve the overall positioning performance. All the proposed methods are tested against a published dataset, which is used as the competition data of the IPIN 2016 Conference with offsite track (track 3).Besides the positioning system based on Wi-Fi technology, the smartphone’s inertial sensors are also useful for the tracking task. The three types of sensors, which are accelerate, gyroscope and magnetic, can be employed to create a Step-And-Heading (SHS) system. Several methods are tested in our approaches. The number of steps and user’s moving distance are calculated from the accelerometer data. The user’s heading is calculated from the three types of data with three methods, including rotation matrix, Complimentary Filter and Madgwick Filter. It is reasonable to combine SHS outputs with the outputs from Wi-Fi due to both technologies are present in the smartphone. Two combination approaches are tested. The first approach is to use directly the Wi-Fi outputs as pivot points for fixing the SHS tracking part. In the second approach, we rely on the Wi-Fi signal to build an observation model, which is then integrated into the particle filter approximation step. The combining paths have a significant improvement from the SHS tracking only and the Wi-Fi only. Although, SHS tracking with Wi-Fi fingerprinting improvement achieves promising results, it has a number of limitations such as requiring additional sensors calibration efforts and restriction on smartphone handling positions.In the context of multiple users, Bluetooth technology on the smartphone could provide the approximated distance between users. The relative distance is calculated from the Bluetooth inquiry process. It is then used to improve the output from Wi-Fi positioning models. We study two different combination methods. The first method aims to build an error function which is possible to model the noise in the Wi-Fi output and Bluetooth approximated distance for each specific time interval. It ignores the temporal relationship between successive Wi-Fi outputs. Position adjustments are then computed by minimizing the error function. The second method considers the temporal relationship and the movement constraint when the user moves around the area. The tracking step are carried out by using particle filter. The observation model of the particle filter are a combination between the Wi-Fi data and Bluetooth data. Both approaches are tested against real data, which include up to four different users moving in an office environment. While the first approach is only applicable in some specific scenarios, the second approach has a significant improvement from the position output based on Wi-Fi fingerprinting model only.
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