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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.
111

Content repurposing of electrical diagrams for presentation in handheld devices

Papaliakos, Vasilios 12 1900 (has links)
Approved for public release, distribution is unlimited / This thesis proposes a design for content repurposing of electrical diagrams for presentation in small-screen wireless handheld devices. Content repurposing is the on-line adaptation of content to fit device capabilities and user's preferences. The focus of this thesis is on electrical diagrams of the schematic type used for maintenance purposes. Nevertheless, many of the proposed techniques are suitable for other technical drawings as well. A significant amount of work has been done in summarization of Web documents and in diagram recognition, but not for presentation of diagrams in handheld devices. In the design proposed here, techniques are proposed for understanding the semantics of electrical diagrams and for partitioning the drawing images in intelligent ways to formulate coherent units for presentation to the user. / Lieutenant, Hellenic Navy
112

以雲端支援架構建置RFID為基礎之個人化無所不在學習系統 / A cloud-supported framework for implementing RFID-based personalized ubiquitous learning system

林彥志, Lin, Yen Chih Unknown Date (has links)
本研究提出一項無所不在的學習系統架構改變傳統數位學習之教育傳遞的方式,讓學習者能在任何時間、任何地點透過行動裝置,連結雲端上的學習系統便能自動取得數位化的教學課程及輔助教材等教學資源,並結合RFID標籤之唯一性及無線辨識功能,除了可感測、讀取周遭環境物件資訊以外,更作為學習者個人辨識登入的方法,進而驗證以取得個人所屬的學習課程或學習進度規劃等功能,創造個人化無所不在學習,期許改善目前數位學習在散播教育資源這塊領域,仍有不足之處所造成的數位落差。系統架構本身採用雲端運算作為後端開發技術,將系統、數位學習課程與資料庫分散在各地,以減少單一系統之資源負載量過大及頻寬不足等問題,讓學習者接受即需的教學服務。 / This paper proposes a ubiquitous learning system framework, in order to improve traditional e-learning method for delivering education. Learners could connect to the learning system on the cloud by mobile devices at any time and any place. It could automatically access digital educational resources such as learning courses and supplementary materials. Using the RFID tag for uniqueness and radio frequency identification function. In addition to context-aware and reading the information of objects around the enviroment. It also can be a personalised identify for learners to login and access one’s own function of learning courses or learning scheduling to create personalized ubiquitous learning. There is lack of education due to digital divide which calls for improvement of distributing educational resources. The proposed system architecture incorporates cloud computing for back-end development technology. In order to reduce resource overload of the single system and lack of bandwidth, distributing the learning system, e-learning course and database to several places enable learners to take on-demand educational services.
113

Cooperative DVB-H: Raptor-Network Coding Protocols for Reliable and Energy Efficient Multimedia Communications

BENACEM, Lucien 05 August 2010 (has links)
Reliable and energy-efficient delivery of multimedia to mobile terminals in dynamic networks is a very challenging problem. In this thesis, we focus on a cooperative extension to the Digital Video Broadcasting – Handheld (DVB-H) standard, forming a cooperative broadcast network whereby terminal-to-terminal cooperation creates a distributed form of multi-input-multi-output (MIMO) that supplements existing fixed network infrastructure. First, we develop a novel and computationally-efficient hierarchical Markov model that is able to accurately perform a cross-layer packet error mapping between the physical and transport layers of the DVB-H/IPDC (IP DataCast) protocol stack. We then construct a discrete-event simulator in MATLAB® that incorporates all of the necessary modules to conduct dynamic multiterminal network simulations. Next, the convergence of cooperative wireless communication, Raptor application layer forward error correction (AL-FEC) and Network Coding (NC) is examined. Originally proposed for broadcasting over the Internet, the application of Raptor codes to wireless cooperative communications networks has been limited to date, but they have been mandated for use in DVB-H. Network coding is used to reduce energy consumption by opportunistically recombining and rebroadcasting required combinations of packets. Two novel coding-enabled cooperative relaying protocols are developed for multicast and multiple unicast file distribution scenarios that are transparent, fully distributed, and backwards compatible with today's systems. Our protocols are able to exploit several different forms of diversity inherent to modern wireless networks, including spatial diversity, radio interface diversity, and symbol diversity. Extensive simulations show that our protocols simultaneously achieve breakthroughs in network energy efficiency and reliability for different terminal classes and densities, allowing greatly improved user experiences. / Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2010-08-03 19:45:54.943
114

Light-tissue interactions for developing portable and wearable optoelectronic devices for sensing of tissue condition, diagnostics and treatment in photodynamic therapy (PDT)

Kulyk, Olena January 2016 (has links)
This thesis presents the development and in-vivo applications of wearable and portable devices for the investigation of light interaction with tissue involved in Photodynamic therapy (PDT) and during contraction of muscles. A hand-held device and a clinical method were developed for time course in-vivo imaging of the fluorescence of the photosensitizer Protoporphyrin IX (PpIX) in healthy and diseased skin with the aim to guide improvement of PDT protocols. The device was used in a small clinical study on 11 healthy volunteers and 13 patients diagnosed with non-melanoma skin cancer (NMSC). Two types of PpIX precursors were administered: Ameluz gel and Metvix® cream. The fluorescence was imaged with a 10 minute time step over three hours which was the recommended metabolism time before commencing PDT treatment at Ninewells Hospital, Dundee. The fluorescence time course was calculated by integrating the areas with the highest intensity. The fluorescence continued to grow in all subjects during the three hours. The time course varied between individuals. There was no statistical significance between either healthy volunteers or patients in Ameluz vs Metvix® groups; nor was there statistical difference between the three lesions groups (Actinic keratosis (AK) Ameluz vs AK Metvix® vs Basal cell carcinoma (BCC) Metvix®). The p-value was larger than 0.05 in a two sample t-test with unequal variances for all the groups. However, there was strong body site dependence between the head & neck compared to the lower leg & feet, or the trunk & hands body site groups (p-value < 0.01). One of the possible explanations for this was temperature and vasculature variation in skin at different body sites: the temperature is higher and the vasculature structure is denser at the head and the neck compared to the lower leg or the trunk. The temperature was not measured during the study. So in order to support this hypothesis, typical skin temperatures at the lesion sites were taken from the IR thermal images of healthy skin available in literature. PpIX fluorescence had a positive correlation to temperature. If this hypothesis is true, it will be highly important to PDT treatment. Increasing the temperature could speed up the metabolism and reduce the waiting time before starting the treatment; ambient temperature should be taken into account for daylight PDT; cooling air as pain management should be administered with caution. Potential improvements for wearable PDT light sources were investigated by modelling light transport in skin for the current LED-based Ambulight PDT device, a commercial OLED for future devices and a directional OLED developed in the group. The optical models were implemented in commercial optical software (with intrinsic Monte Carlo ray tracing and Henyey-Greenstein scattering approximation) which was validated on diffuse reflectance and transmittance measurements using in-house made tissue phantoms. The modelling was applied to investigate the benefits from diffusive and forward scattering properties of skin on light transmission in treatment light sources. 1 mm thick skin can only compensate approximately 10% of non-uniform irradiance. It means that uniform illumination is crucial for the treatment light sources. Forward scattering in skin showed a 10% improved light transmission from a collimated emission compared to a wide angle Lambertian emission. However, depth-dependent transmission measurements of directional vs Lambertian emission from organic light emitting films (a nano-imprinted grating was fabricated to provide directional emission in one of the films), collimated vs diffused HeNe laser light through fresh porcine skin did not show the expected improvement. This could be explained by skin roughness which was previously found to change the optical properties and may also affect light coupling. The modelling was applied to guide an optical design of another wearable device – a muscle contraction sensor. Muscle is fibrous and because of that scatters light differently in different directions. The sensor detects the change in backscattered light in parallel and perpendicular directions with respect to muscle fibres. The sensor was implemented on a wearable bandage on fully flexible substrate with flexible OLED and organic photodiodes. The major advantages of organic optoelectronic sensing compared to conventional electromyography (EMG) sensors are the ability to distinguish two types of contractions (isotonic and isometric), insensitivity to electromagnetic interference and the absence of an immune response due to non-invasive electrode-free sensing. Optical modelling was performed to understand the operation of the sensor. A 3D anisotropic optical model of scattering in muscle was created by geometrical manipulations with the standard Henyey-Greenstein scattering volumes. The penetration depth from the Super Yellow OLED was found to be 20-25 mm; the optimal separation between the source and the detector was found to be 20 mm. This distance provided a still detectable signal along with the best discrimination between the two backscatterings. When a 2 mm thick layer of skin and a 2 mm thick layer of adipose tissue were added to the model, the signal was hugely diffused. The discrimination between the two backscatterings decreased by three orders of magnitude, the penetration depth in muscle was reduced, and the intensity of the signal dropped down but was still detectable. With 5 mm thick adipose tissue and 2 mm thick skin the signal was too diffused and interacted with very shallow layers of muscle which approached the limits of the optical sensing of muscle activity.
115

Capteur de mouvement intelligent pour la chirurgie prothétique naviguée / Smart motion sensor for navigated prosthetic surgery

Claasen, Göntje Caroline 17 February 2012 (has links)
Nous présentons un système de tracking optique-inertiel qui consiste en deux caméras stationnaires et une Sensor Unit avec des marqueurs optiques et une centrale inertielle. La Sensor Unit est fixée sur l'objet suivi et sa position et orientation sont déterminées par un algorithme de fusion de données. Le système de tracking est destiné à asservir un outil à main dans un système de chirurgie naviguée ou assistée par ordinateur. L'algorithme de fusion de données intègre les données des différents capteurs, c'est-à-dire les données optiques des caméras et les données inertielles des accéléromètres et gyroscopes. Nous présentons différents algorithmes qui rendent possible un tracking à grande bande passante avec au moins 200Hz avec des temps de latence bas grâce à une approche directe et des filtres dits invariants qui prennent en compte les symmétries du système. Grâce à ces propriétés, le système de tracking satisfait les conditions pour l'application désirée. Le système a été implementé et testé avec succès avec un dispositif expérimental. / We present an optical-inertial tracking system which consists of two stationary cameras and a Sensor Unit with optical markers and an inertial measurement unit (IMU). This Sensor Unit is attached to the object being tracked and its position and orientation are determined by a data fusion algorithm.The tracking system is to be used for servo-controlling a handheld tool in a navigated or computer-assisted surgery system.The data fusion algorithm integrates data from the different sensors, that is optical data from the cameras and inertial data from accelerometers and gyroscopes. We present different algorithms which ensure high-bandwidth tracking with at least 200Hz with low latencies by using a direct approach and so-called invariant filters which take into account system symmetries. Through these features, the tracking system meets the requirements for being used in the desired application.The system was successfully implemented and tested with an experimental setup.
116

Mätosäkerhet vid digital terrängmodellering med handhållen laserskanner : Undersökning av den handhållna laserskannern ZEB-REVO

Gustafsson, Amanda, Wängborg, Olov January 2018 (has links)
En digital terrängmodell (DTM) är en representation av enbart själva markytan. Det finns flera metoder för att framställa DTM:er, där laserskanning har blivit en alltmer vanlig metod. Inom laserskanning är flygburen laserskanning (FLS) en flitigt använd metod, då metoden har fördelen av att kunna täcka stora områden på kort tid. Det finns dock nackdelar med FLS då datainsamlingen kan bli bristfällig i t.ex. skogsområden, där laserstrålar inte kan tränga igenom tät vegetation. Här kan handhållen laserskanning (HLS) vara ett bra alternativ då HLS går snabbt och inte behöver samma omfattande planering. Tidigare studier visar att HLS har många fördelar, men som dock inte kan hålla samma låga osäkerhet som terrester laserskanning (TLS). Det saknas däremot studier om hur HLS ställer sig mot mätningar med FLS. Syftet med studien är därför att utvärdera möjligheten att använda och tillämpa mätningar med HLS för framställning av DTM i skogsterräng gentemot FLS. Detta görs genom att jämföra respektive DTM:s lägesosäkerhet. I studien användes instrumentet ZEB-REVO för insamlingen av data för metoden HLS. Medan för FLS användes laserdata från Lantmäteriet. Från insamlad laserdata skapades därefter DTM:er. Dessa jämfördes mot ett antal kontrollprofiler som mättes in med totalstation. För respektive metod, HLS och FLS, beräknades medelvärde för höjdavvikelserna mot kontrollprofilerna där även standardavvikelse beräknades. Resultatet visar att DTM:en skapad av data från FLS beräknades ha en höjdavvikelse för hela området på 0,055 m som medelvärde gentemot inmätta kontrollprofiler. Standardavvikelsen för denna höjdavvikelse beräknades till 0,046 m för FLS. För DTM:en med data från HLS beräknades en höjdavvikelse på 0,043 m i medelvärde som bäst, där standardavvikelse beräknades till 0,034 m. Studien visar att metoderna HLS och FLS gav likvärdiga resultat gentemot de inmätta kontrollprofilerna, dock gav HLS generellt mindre standardavvikelse i jämförelse mot FLS. Vidare ansågs ZEB-REVO och dess tillhörande databearbetningsprogram GeoSLAM vara väldigt användarvänligt, där själva skanningen med instrumentet tog endast 10 minuter för studiens område på ca 2000 m2. Utifrån studiens resultat drogs slutsatsen att mätningar med HLS kan ge en likvärdig DTM, sett till osäkerheten, som FLS-mätningar. HLS kan därmed vara en kompletterande metod men att FLS är en fortsatt effektiv metod. / A digital terrain model (DTM) represent exclusively the earth surface. There are several methods which can be utilized to create DTMs, where laser scanning have become a common used method. Airborne laser scanning (ALS) is often used since the method can cover a large area in a relatively short time. However a disadvantage with ALS is that the data collection, for a wooded area, can be inadequate due to penetration difficulties for some laser beams. For that reason a handheld laser scanner (HLS) can be an alternative since measurements can be done fast and does not need the same extensive planning. Earlier studies mention HLS to have several advantages but can still not yet be compared with terrestrial laser scanning (TLS) concerning the measurements uncertainty. There are, however, no studies that investigates how measurements with HLS stands against FLS. The purpose with the study is to evaluate the ability to use measurements from HLS to create a DTM for a wooded area in comparison with ALS. This is done by comparing the different uncertainties for each DTM. In the study the acquisition of HLS laser data was collected with the instrument ZEB-REVO and the ALS laser data was received from Lantmäteriet (cadastral mapping and surveying authority in Sweden). After the data acquisition a DTM were created from each data set (method). The DTMs were then compared to control profiles, which have been measured with total station. From the comparison with the control profiles average height deviation and standard deviation were calculated for each DTM. The result shows that the DTM created from ALS data received an average height deviation of 0,055 m for the whole area with a standard deviation of 0,046 m. Corresponding result for the DTM created from HLS data were calculated, at best, to 0,043 m in average height deviation and 0,034 m in standard deviation. The study shows that the methods HLS and ALS gave equivalent result regarding the comparison with the control profiles, however HLS gave a generally lower value for standard deviation. Furthermore ZEB-REVO with its processing program GeoSLAM was considered to be very easy and user friendly. The area (approx. 2000 m2) for the study was scanned within only 10 min. The conclusion which were drawn from the obtained result was that measurements with HLS can generate an equivalent DTM, concerning the uncertainty, as measurements with FLS. Thereby HLS can be a complementing method but still FLS is seen as an effective method.
117

3D handheld endoscope for optical coherence tomography of the human oral mucosa in vivo

Walther, Julia, Schnabel, Christian, Ebert, Nadja, Baumann, Michael, Koch, Edmund 06 September 2019 (has links)
The early non-invasive diagnosis of epithelial tissue alterations in daily clinical routine is still challenging. Since optical coherence tomography (OCT) shows the potential to differentiate between benign and malignant tissue of primal endothelium, OCT could be beneficial for the early diagnosis of malignancies in routine health checks. In this research, a new handheld endoscopic scanning unit was designed and connected to a spectral domain OCT system of our workgroup for the in vivo imaging of the human oral mucosa.
118

Contribution à la validation d’un outil informatique pour l’évaluation des surfaces corporelles brûlées

Matei, Svetlana 08 1900 (has links)
INTRODUCTION L’évaluation de la surface corporelle brûlée, essentielle pour établir la réanimation volémique et statuer sur le pronostic, se base actuellement sur la transposition des brûlures observées sur des diagrammes en papier représentant des mannequins standard. Le but de ce projet est de contribuer à la validation d’un outil pour l’évaluation des ratios brûlés. Deux outils ont été proposés, un numériseur portable et les mesures anthropométriques. MÉTHODES Quatre mannequins commerciaux avec différentes morphologies ont été sélectionnés. Chaque mannequin a été numérisé 10 fois avec un numériseur portable et une fois avec un numériseur de référence. Les surfaces corporelles totales ont été calculées et comparées. Dans un deuxième temps, 14 volontaires ont estimé la surface coporelle brûlée en utilisant les diagrammes papier et en dessinant sur un logiciel. RÉSULTATS Les valeurs des surfaces corporelles totales obtenues avec le numériseur portable sont 0,812; 1,581; 1,711 et 1,916 m2 pour les mannequins enfant, femme I, femme II et homme. Les résultats du numériseur de référence sont 0,815; 1,588; 1,716 et 1,918 m2. Les ratios des surfaces brûlées des mannequins correspondent à 23,33; 22,67, 32,63 et 26,07 % pour les mannequins. Les estimations des surfaces brûlées obtenues avec les diagrammes en papier représentent 29,9; 32,5; 40,4 et 35,7 %. Les résultats obtenus avec le logiciel sont 23,5; 22,6; 32,1 et 25,1 %. CONCLUSION Le numériseur portable reproduit avec précision et exactitude la surface corporelle totale. L’utilisation des données anthropométriques pour le calcul du pourcentage brûlé représente un outil plus précis et exact que les diagrammes papier. / PURPOSE Total body surface area burned assessment is currently based on the transpositon of burns seen on paper charts representing standard models. The purpose of this project is to contribute to the validation of a tool for TBSA assessment. A handheld 3D scanner and anthropometrical measurements have been proposed. METHODS Four commercial mannequins with different body shapes were selected. Each model was scanned 10 times with a handhed, white light scanner and once with a gold standard scanner. The images were transferred to a modelling software allowing to assess the total body surface. Total body surfaces were calculated and compared. Secondly, 14 volunteers estimated the total burned surface using paper charts and drawing on 3D virtual models. RESULTS Values of the total body surface obtained with the handheld scanner are 0.812; 1.581; 1.711 and 1.916 m2 for the child, female I, female II and male mannequins. The results of the gold standard scanner are 0.815 ; 1.588 ; 1.716 and 1.918 m2. Burn extent ratios correspond to 23.33 ; 22.67 ; 32.63 and 26.07 % for the same mannequins. Estimated burned surfaces obtained with paper diagrams are the following : 29.9 ; 32.5 ; 40.4 and 35.7 %. Results obtained with the software are 23.5 ; 22.6 ; 32.1 and 25.1 %. CONCLUSION The handheld scanner is a precise and accurate tool for the assessment of the total surface. Use of anthropometric data for the calculation of the body burned surface is a more accurate tool and less variable than the conventional paper charts.
119

The Spillable Environment: Expanding a Handheld Device's Screen Real Estate and Interactive Capabilities

Clement, Jeffrey S. 07 August 2007 (has links) (PDF)
Handheld devices have a limited amount of screen real estate. If a handheld device could take advantage of larger screens, it would create a more powerful user interface and environment. As time progresses, Moore's law predicts that the computational power of handheld devices will increase dramatically in the future, promoting the interaction with a larger screen. Users can then use their peripheral vision to recognize spatial relationships between objects and solve problems more easily with this integrated system. In the spillable environment, the handheld device uses a DiamondTouch Table, a large, touch-sensitive horizontal table, to enhance the viewing environment. When the user moves the handheld device on the DiamondTouch, the orientation of the application changes accordingly. A user can let another person see the application by rotating the handheld device in that person's direction. A user could conveniently use this system in a public area. In a business meeting, a user can easily show documents and presentations to other users around the DiamondTouch table. In an academic setting, a tutor could easily explain a concept to a student. A user could effortlessly do all of this while having all of his/her information on the handheld device. A wide range of applications could be used in these types of settings.
120

Fiber Optic Sensor Interrogation Advancements for Research and Industrial Use

Kunzler, Wesley Mont 17 March 2011 (has links) (PDF)
Spectrally-based fiber optic sensors are a rapidly maturing technology capable of sensing several environmental parameters in environments that are unfitting to electrical sensors. However, the sensor interrogation systems for this type of sensors are not yet fit to replace conventional sensor systems. They lack the speed, compact size, and usability necessary to move into mainstream test and measurement. The Fiber Sensor Integrated Monitor (FSIM) technology leverages rapid optical components and parallel hardware architecture to move these sensors across the research threshold into greater mainstream use. By dramatically increasing speed, shrinking size, and targeting an interface that can be used in large-scale industrial interrogation systems, spectrally-based fiber optic sensors can now find more widespread use in both research labs and industrial applications. The technology developed in this thesis was demonstrated by producing two advanced interrogators: one that was one half the size of commercially available systems, and one that accelerated live spectral capture by one thousand times – both of which were operated by non-developers with little training.

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