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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.
471

網路外部性的創造與管理-以Garmin Sports為例 / The network externality of platform – A case study of Sport Industry

林逸安 Unknown Date (has links)
近年來,國人追求健康、愛美等因素而運動風氣蔚為盛行,連帶擴大穿戴型裝置產業發展,越來越多廠商加入。而在競爭激烈的全球市場中,不少廠商以平台經濟模式的建立及善用網路外部性的發展為轉型的策略,其中,如何有效率擴大平台規模及提高顧客黏著度尤其重要。本研究著重於以下三點:個案公司之平台商業模式的運作機制、如何創造不同種類之網路外部性及如何管理網路外部性創造更多效益。 本研究採取單一個案研究法,並挑選從GPS大廠成功涉足智慧型穿戴式裝置且近年來積極轉型之台灣國際航電股份有限公司(Garmin Corp.),經過研究個案公司平台商業模式與網路外部性的創造及管理,歸納本研究之發現:Garmin透過Garmin Sports平台的管理,建立與外部用戶的關係;並藉由穿戴式裝置的租借與其他廠商合作活動帶動運動市場貿易;再教練培訓為中心出發,提供一套專業、完整的課程,建立平台生態圈,擴大平台規模。 本研究之貢獻在於透過Garmin Sports的案例建立一套平台發展與網路外部性的創造與管理之架構,以期了解透過平台網路外部性發展如何提升使用者價值、為使用者帶來更多效益。歸納出三項因素如下: 1. 專業人士與外部廠商 2. 互補品的發展與資料庫的建立 3. 透過多方用戶的選擇與舉辦活動來管理網路外部性 此外,本研究為Garmin Sports平台成立初期,上線時間較短,部分網路外部性的交互影響研究受限。故建議後續研究,可待Garmin Sports平台運作期間較長,其網路外部性的創造與管理及不同種類網路外部性之相互作用亦會較為明顯。 / In recent years, the atmosphere of physical workout becomes prevalent, which results in the expansion of wearable device industry, causing more and more companies join in this industry. Under such a highly competitive global markets, platform transformation gradually becomes a popular strategy. In the research, our main focus lies on what the platform business model is and how to create and manage different kind of network externality. The case study method is applied for this research. We select Garmin Corp, a GPS corporation which successfully develops wearable devices in recent years and has transformed into a new business model as our research subject. With in-depth case study of platform business model and the creation and management of network externality, we conclude our findings as below: Garmin establishes the relationship with external users and cooperates with other companies through the management of the Garmin Sports platform by leasing wearable devices. To expand the scale of the platform, Garmin provides a set of professional training camp and competitions, so as to establish the platform ecosystem. The academic contribution of this study is to create the structure of developing platform and managing network externality, hoping to bring more value and benefits. The factors are as below: 1. Experts and external companies 2. Complementary products and database setup 3. multi-user selection and managing network externality through events In addition, this study is about the beginning of Garmin Sports platform in which on-line time is short and the interaction of network externality is limited. It is recommended that, for the follow-up research, researches should wait for Garmin Sports platform to operate for a longer period of time. Therefore, the creation and management of network externalities and the different types of network interaction will be more obvious.
472

Data Verifications for Online Social Networks

Rahman, Mahmudur 10 November 2015 (has links)
Social networks are popular platforms that simplify user interaction and encourage collaboration. They collect large amounts of media from their users, often reported from mobile devices. The value and impact of social media makes it however an attractive attack target. In this thesis, we focus on the following social media vulnerabilities. First, review centered social networks such as Yelp and Google Play have been shown to be the targets of significant search rank and malware proliferation attacks. Detecting fraudulent behaviors is thus paramount to prevent not only public opinion bias, but also to curb the distribution of malware. Second, the increasing use of mobile visual data in news networks, authentication and banking applications, raises questions of its integrity and credibility. Third, through proof-of- concept implementations, we show that data reported from wearable personal trackers is vulnerable to a wide range of security and privacy attacks, while off-the-shelves security solutions do not port gracefully to the constraints introduced by trackers. In this thesis we propose novel solutions to address these problems. First, we introduce Marco, a system that leverages the wealth of spatial, temporal and network information gleaned from Yelp, to detect venues whose ratings are impacted by fraudulent reviews. Second, we propose FairPlay, a system that correlates review activities, linguistic and behavioral signals gleaned from longitudinal app data, to identify not only search rank fraud but also malware in Google Play, the most popular Android app market. Third, we describe Movee, a motion sensor based video liveness verification system, that analyzes the consistency between the motion inferred from the simultaneously and independently captured camera and inertial sensor streams. Finally, we devise SensCrypt, an efficient and secure data storage and communication protocol for affordable and lightweight personal trackers. We provide the correctness and efficacy of our solutions through a detailed theoretic and experimental analysis.
473

Video event detection and visual data pro cessing for multimedia applications

Szolgay, Daniel 30 September 2011 (has links)
Cette thèse (i) décrit une procédure automatique pour estimer la condition d'arrêt des méthodes de déconvolution itératives basées sur un critère d'orthogonalité du signal estimé et de son gradient à une itération donnée; (ii) présente une méthode qui décompose l'image en une partie géométrique (ou "cartoon") et une partie "texture" en utilisation une estimation de paramètre et une condition d'arrêt basées sur la diffusion anisotropique avec orthogonalité, en utilisant le fait que ces deux composantes. "cartoon" et "texture", doivent être indépendantes; (iii) décrit une méthode pour extraire d'une séquence vidéo obtenue à partir de caméra portable les objets de premier plan en mouvement. Cette méthode augmente la compensation de mouvement de la caméra par une nouvelle estimation basée noyau de la fonction de probabilité de densité des pixels d'arrière-plan. Les méthodes présentées ont été testées et comparées aux algorithmes de l'état de l'art. / This dissertation (i) describes an automatic procedure for estimating the stopping condition of non-regularized iterative deconvolution methods based on an orthogonality criterion of the estimated signal and its gradient at a given iteration; (ii) presents a decomposition method that splits the image into geometric (or cartoon) and texture parts using anisotropic diffusion with orthogonality based parameter estimation and stopping condition, utilizing the theory that the cartoon and the texture components of an image should be independent of each other; (iii) describes a method for moving foreground object extraction in sequences taken by wearable camera, with strong motion, where the camera motion compensated frame differencing is enhanced with a novel kernel-based estimation of the probability density function of the background pixels. The presented methods have been thoroughly tested and compared to other similar algorithms from the state-of-the-art.
474

Data Acquisition and Processing Pipeline for E-Scooter Tracking Using 3D LIDAR and Multi-Camera Setup

Siddhant Srinath Betrabet (9708467) 07 January 2021 (has links)
<div><p>Analyzing behaviors of objects on the road is a complex task that requires data from various sensors and their fusion to recreate movement of objects with a high degree of accuracy. A data collection and processing system are thus needed to track the objects accurately in order to make an accurate and clear map of the trajectories of objects relative to various coordinate frame(s) of interest in the map. Detection and tracking moving objects (DATMO) and Simultaneous localization and mapping (SLAM) are the tasks that needs to be achieved in conjunction to create a clear map of the road comprising of the moving and static objects.</p> <p> These computational problems are commonly solved and used to aid scenario reconstruction for the objects of interest. The tracking of objects can be done in various ways, utilizing sensors such as monocular or stereo cameras, Light Detection and Ranging (LIDAR) sensors as well as Inertial Navigation systems (INS) systems. One relatively common method for solving DATMO and SLAM involves utilizing a 3D LIDAR with multiple monocular cameras in conjunction with an inertial measurement unit (IMU) allows for redundancies to maintain object classification and tracking with the help of sensor fusion in cases when sensor specific traditional algorithms prove to be ineffectual when either sensor falls short due to their limitations. The usage of the IMU and sensor fusion methods relatively eliminates the need for having an expensive INS rig. Fusion of these sensors allows for more effectual tracking to utilize the maximum potential of each sensor while allowing for methods to increase perceptional accuracy. </p> <p>The focus of this thesis will be the dock-less e-scooter and the primary goal will be to track its movements effectively and accurately with respect to cars on the road and the world. Since it is relatively more common to observe a car on the road than e-scooters, we propose a data collection system that can be built on top of an e-scooter and an offline processing pipeline that can be used to collect data in order to understand the behaviors of the e-scooters themselves. In this thesis, we plan to explore a data collection system involving a 3D LIDAR sensor and multiple monocular cameras and an IMU on an e-scooter as well as an offline method for processing the data to generate data to aid scenario reconstruction. </p><br></div>
475

Interactive Design Interfaces to support Ideation & Rapid Prototyping

Devashri Utpal Vagholkar (11816888) 19 December 2021 (has links)
Generating ideas and creating prototypes of physical products is a highly non-linear and iterative process. Current tools divide this process into multiple discrete steps with different tools to support each of these steps such as CAD modelling, simulation and fabrication. We believe, design interfaces that combine different steps of the process and create different layers of abstraction depending on the type of the user and where they are in the process can support users in generating more creative ideas and creating better functioning prototypes more efficiently. In order to validate this, we developed three interfaces- a sketch-based ideation tool, a live programming interface to create IoT devices and a design tool to support design and fabrication of hand wearables. The foundation of these design interfaces is the layer of abstraction that allows users to focus on idea generation and converting it into a tangible prototype with little or no technical knowledge, and a continuous visual feedback that guides the user to make necessary changes to improve their design. The three tools were evaluated through user testing for supporting creation of different ideas and converting them into functional prototypes.
476

Application-Specific Things Architectures for IoT-Based Smart Healthcare Solutions

Sundaravadivel, Prabha 05 1900 (has links)
Human body is a complex system organized at different levels such as cells, tissues and organs, which contributes to 11 important organ systems. The functional efficiency of this complex system is evaluated as health. Traditional healthcare is unable to accommodate everyone's need due to the ever-increasing population and medical costs. With advancements in technology and medical research, traditional healthcare applications are shaping into smart healthcare solutions. Smart healthcare helps in continuously monitoring our body parameters, which helps in keeping people health-aware. It provides the ability for remote assistance, which helps in utilizing the available resources to maximum potential. The backbone of smart healthcare solutions is Internet of Things (IoT) which increases the computing capacity of the real-world components by using cloud-based solutions. The basic elements of these IoT based smart healthcare solutions are called "things." Things are simple sensors or actuators, which have the capacity to wirelessly connect with each other and to the internet. The research for this dissertation aims in developing architectures for these things, focusing on IoT-based smart healthcare solutions. The core for this dissertation is to contribute to the research in smart healthcare by identifying applications which can be monitored remotely. For this, application-specific thing architectures were proposed based on monitoring a specific body parameter; monitoring physical health for family and friends; and optimizing the power budget of IoT body sensor network using human body communications. The experimental results show promising scope towards improving the quality of life, through needle-less and cost-effective smart healthcare solutions.
477

Energy Harvesting Power Supply for MEMS Applications / Energy Harvesting Power Supply for MEMS Applications

Smilek, Jan January 2018 (has links)
Tato práce se zabývá vývojem nezávislého elektrického zdroje pro moderní nízkopříkonové elektrické aplikace. Protože tradiční řešení napájení drobných spotřebičů s využitím baterií či akumulátorů snižuje uživatelský komfort kvůli potřebě pravidelné údržby, navrhovaný zdroj využívá principu energy harvesting. Tento princip spočívá v získávání energie přímo z okolního prostředí napájené aplikace a její přeměně na energii elektrickou, která je dále využita pro na-pájení moderních MEMS (mikroelektromechanických) zařízení. Potenciální aplikací vyvíjeného zdroje je především moderní nositelná elektronika a biomedicínské senzory. Tato oblast využití ovšem klade zvýšené nároky na parametry generátoru, který musí zajistit dostatečný generovaný výkon z energie, dostupné v okolí lidského těla, a to při zachování prakticky využitelné velikosti a hmotnosti. Po stanovení předběžných požadavků a provedení analýz vhodnosti dostupných zdrojů energie ke konverzi byla k využití vybrána kinetická energie lidských aktivit. Byla provedena série měření zrychlení na lidském těle, především v místě předpokládaného umístění generátoru, aby bylo možno analyzovat a generalizovat hodnoty energie dostupné ke konverzi v daném umístění. V návaznosti na tato měření a analýzy byl vyvinut inovativní kinetický energy harvester, který byl následně vyroben jako funkční vzorek. Tento vzorek byl pak testován v reálných podmínkách pro verifikaci simulačního modelu a vyhodnocení reálné použitelnosti takového zařízení. Kromě samotného vývoje generátoru je v práci popsán i originální způsob zvýšení generovaného výkonu pro kinetické energy harvestery a jsou prezentována statistická data a modely pro predikci využitelnosti kinetických harvesterů pro získávání energie z lidské aktivity.
478

Návrh a optimalizace senzorických systémů využívajících malovýkonových napájecích generátorů / The Sensor Systems Design and Optimization for Energy Harvesting Applications

Žák, Jaromír January 2015 (has links)
Dissertation thesis is focused on using alternative energy sources called energy harvesting. This thesis offers a solution to problems with autonomous powering of sensor networks if primary power source recovery is impossible. In these cases, energy of the external power (e.g. temperature, light, motion) should be used. Proposed solution should be especially used in the field of medical applications (e.g. cochlear implants, pacemakers, insulin pumps). Long time monitoring of the personal health status is also possible when employing automated sensor systems. In this work, there is state of art review relating to the low power energy sources for an alternative powering of sensor systems. It was observed that existing systems are almost prepared for the implementation of energy harvesting power sources. The energy harvesting power sources have been developed by numerous researcher teams around the world, but there are only a few variants of power management circuits for effective energy gaining, storing and using. This area has a huge potential for the next research. The issues regarding to the distribution of gained energy are solved on the complex level in the thesis. For these purposes, a new simulation model of the whole system (fully implantable artificial cochlea) including its subcircuits was developed in the SPICE environment. It connects independent subcircuits into a single comprehensive model. Using this model, a few novel principles for energy distribution (e.g. Charge Push Through technique) was developed. In the near future, these techniques are also applicable to the design of versatile sensor systems.
479

Wearables im industriellen Einsatz: Befähigung zu mobiler IT-gestützter Arbeit durch verteilte tragbare Benutzungsschnittstellen

Ziegler, Jens 10 December 2015 (has links)
Die industrielle Instandhaltung ist ein erheblicher Kostenfaktor während der Betriebsphase einer verfahrenstechnischen Produktionsanlage. Insbesondere der Mangel an technischen Möglichkeiten zum Informationsaustausch des Instandhaltungspersonals mit der digitalen Anlage während der Arbeiten im Feld erzeugt hohe Kosten. Durch die entstehenden Medienbrüche sinkt die Qualität der Informationen in der Digitalen Anlage erheblich. Mobile Informationssysteme können diese Medienbrüche beseitigen und die Informationsqualität in der Digitalen Anlage entscheidend verbessern. Das Konzept der Distributed Wearable User Interfaces (DWUI) stellt einen integrierten Ansatz zur flexiblen Zusammenstellung gebrauchstauglicher Benutzungsschnittstellen für komplexe Arbeitsabläufe in widrigen Arbeitssituationen bereit. Diese setzen sich aus Interaktionsgeräten zusammen, die in einem kabellosen körpernahen Funknetzwerk miteinander verbunden sind und in ihrer Kombination die Benutzungsschnittstelle zu einem mobilen System bilden. Die Geräte sind ergonomisch und funktional optimal am Körper des Nutzers verteilt, wobei jedes Gerät eigenständig nutzbar und für eine bestimmte Aufgabe oder einen bestimmten Nutzungskontext optimiert ist. Die Ein- und Ausgaberäume der Geräte werden in einem integrierten Interaktionsraum harmonisiert. Im Rahmen dieser Arbeit wird zunächst der Nutzungskontext der mobilen IT-gestützten Instandhaltung verfahrenstechnischer Produktionsanlagen im Hinblick auf Nutzungsszenarien und Anwendungsfälle für mobile Informationssysteme festgelegt. Darauf aufbauend werden Anforderungen an derartige Systeme spezifiziert und Gestaltungsgrundlagen und Empfehlungen speziell für DWUI-basierte mobile Informationssysteme erarbeitet. Anschließend wird eine Reihe spezieller Interaktionsgeräte vorgestellt, die verschiedene Interaktionsprinzipien, Techniken und Modalitäten umsetzen. Um diese Geräte in einem kollaborativen DWUI organisieren zu können, wird ein spezielles Kommunikationsprotokoll entworfen und prototypisch umgesetzt. Eine mobile Anwendung zur Instandhaltungsunterstützung wird vorgestellt, welche das DWUI-Kommunikationsprotokoll unterstützt und mit verschiedenen DWUI-Konfigurationen vollständig bedienbar ist. Diese Anwendung wird integriert in ein komplexes Unternehmensnetzwerk, über das sie Zugriff auf industrietypische computergestützte Planungswerkzeuge erhält. Anhand des resultierenden Gesamtsystems werden die prinzipielle Tauglichkeit und die Vorteile des DWUI-Konzepts demonstriert.
480

Electro - Quasistatic Body Communication for Biopotential Applications

Shreeya Sriram (10195706) 25 February 2021 (has links)
<p> </p><div> <div> <div> <p> </p><div> <div> <div> <p> </p><div> <div> <div> <p>The current state of the art in biopotential recordings rely on radiative electromagnetic (EM) fields. In such transmissions, only a small fraction of this energy is received since the EM fields are widely radiated resulting in lossy inefficient systems. Using the body as a communication medium (similar to a ’wire’) allows for the containment of the energy within the body, yielding order(s) of magnitude lower energy than radiative EM communication. The first part of this work introduces Animal Body Communication for untethered rodent biopotential recording and for the first time this work develops the theory and models for animal body communication circuitry and channel loss. In vivo experimental analysis proves that ABC successfully transmits acquired electrocardiogram (EKG) signals through the body with correlation greater than 99% when compared to traditional wireless communication modalities, with a 50x reduction in power consumption. The second part of this work focusses on the analysis and design of an Electro-Quasistatic Human Body Communication (EQS-HBC) system for simultaneous sensing and transmission of biopotential signals. In this work, detailed analysis on the system level interaction between the sensing and transmitting circuitry is studied and a design to enable simultaneous sensing and transmission is proposed. Experimental analysis was performed to understand the interaction between the Right Leg-Drive circuitry and the HBC transmission along with the effect of the ADC quantization on signal quality. Finally, experimental trials proves that EKG signals can be transmitted through the body with greater than 96% correlation when compared to Bluetooth systems at extremely low powers. </p> </div> </div> </div> </div> </div> </div> </div> </div> </div>

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