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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.
81

Lost & Found Videothek Non-Ubiquitous Video Library for Serendipitous Retrieval of Movies. A Design Exploration for the Introduction of Folksonomy in the Physical Space

Di Giovanni, Bianca January 2017 (has links)
Lost&Found Videothek is the concept for an interactive video library thought for users engaged in an exploratory research mode, in which content is organized according to a collaborative, subjective and implicit indexing system for the enhancement of serendipity. This idea was the result of a design-based research with a user-centered approach in the field of information retrieval. With the use of design methods such as heuristic UX evaluation, co-sketching, and other original design experiments, the project aimed at identifying the most valuable qualities of physical and digital libraries in order to integrate them within one retrieval system.
82

The effect of network coexistence on the performance of wireless sensor networks

Ros Fornells, Oriol January 2016 (has links)
With the coming growth in Internet of Things (IoT) applications, we can expect environ-ments with many independent networks operating in nearby locations. Wireless Sensor Networks (WSN), which have become popular during the last few years, are the main type of networks used in IoT. The IEEE 802.15.4 protocol designed for low-rate wireless personal area networks has been widely adopted for this kind of network. Together with ZigBee, this protocol is gaining increasing interest from the industry, as they are con-sidered a universal solution for low-cost, low-power, wireless connected monitoring and control devices. Internetwork interference issues in IEEE 802.15.4 networks can be a ma-jor problem because of the extensive use of wireless channels. In this thesis, an in-depth simulation study of the internetwork interferences is performed using Castalia, a widely used network simulator. We focus on the beacon collision problem, as it has been proved to be the main cause of performance degradation for coexisting networks. We carry out a prestudy of the main node simulation parameters to setup the different scenarios. Then, we evaluate how the overlap of the active periods and the location of the nodes affect the network performance. We continue with a network coexistence analysis to study the inter-action of two networks of two nodes and their performance regarding the beacon reception rate. We show that there are significantly different operation regions, depending on the network location. Following this, a probabilistic analysis is carried out in order to obtain an average beacon reception rate depending on the size of the area considered. Finally, we discuss available beacon collisions avoidance methods, taking into account the detailed simulation results. Our conclusions have theoretical and practical implications for the design of wireless sensor networks, and for the evaluation of beacon collisions avoidance schemes. / Med den kommande tillväxten i sakernas Internet (IoT) applikationer är miljöer med många oberoende nätverk som verkar på närliggande ställen väntat. Trådlösa sensornätverk (WSN), som har blivit populära under de senaste åren, är den vanligaste typen av nät som används i sakernas Internet. IEEE 802.15.4 protokollen, konstruerad för låghastighet trådlösa personlig area nätverk, har fått stor spridning för WSNs. Tillsammans med ZigBee, får de en snabb ökat intresse från industrin, eftersom de betraktas som en universallösning för låg kostnad låg energi trådlös anslutning för övervaknings- och kontrollinstrument. Internätverk interferens i IEEE 802.15.4 nätverk kan vara ett stort problem på grund av den omfattande användningen av trådlösa kanaler. I denna avhandling är en djupgående simulation studie utfört med hjälp av Castalia, ett utbrett använt nätverk simulator. Vi fokuserar på beacon kollisionsproblem, eftersom det har visat sig vara den främsta orsaken till prestandaförsämring för samexisterande nätverk. Vi utför en förstudie av den viktigaste simulation parametrarna för att bestemma de olika scenarierna. Sedan utvärderar vi hur överlappningen av de aktiva perioderna och placeringen av noderna påverkar nätverkets prestanda. Vi fortsätter med en nätverksamexistens analys för att studera interaktionen mellan två nätverk av två noder, och deras prestanda avseende beacon mottagnings kvot. Vi visar att det finns betydligt olika operationsområdena, beroende på nätverksens placering. Därefter är en sannolikhetsanalys utfört för att erhålla en genomsnittlig beacon mottagnings kvot, beroende på storleken på betraktade områden. Slutligen diskuterar vi tillgängliga metoder för att undvika beacon kollision, med hänsyn till de detaljerade simuleringsresultaten. Våra slutsatser har teoretiska och praktiska kon-sekvenser för utformningen av trådlösa sensornätverk, och för utvärderingen a metoder för att undvika beacon kollision.
83

Wireless Body Area Network for Patient Monitoring in Hospitals

Vinod Kalkotwar, Divya January 2016 (has links)
The master thesis is a prototyping project of a wireless body area network (WBANs) for patient monitoring in hospitals. The goal of this project was to study various technologies suitable for wireless body area networks, complete a requirement analysis, design a WBAN suitable to achieve the requirements and to test and evaluate the system against the requirements. Seven sensor end nodes are chosen to monitor seven vital signs for patient monitoring. After studying different technologies suitable for WBANs, IEEE 802.15.4j was chosen because it communicates in a special allocation of medical spectrum of 2360 to 2400MHz. A coordinator or master will be the center of the network using a star topology. Due to certain limitations in the firmware of the NXP FRDMKW40Z, IEEE 802.15.4j had to be dropped and IEEE 802.15.4 was the final chosen technology because the only difference between IEEE 802.15.4j and IEEE802.15.4 is the difference in the physical layer, while the developed application remains the same, making the shift back to IEEE802.15.4j, in the future, simple. There have been several projects working on the same idea with IEEE 802.15.4, but they do not combine multiple sensors to form a network and the total throughput requirements for this thesis project are much higher. The beacon mode and the non-beacon mode of IEEE 802.15.4 are studied. Non beacon mode is unpredictable due to the use of carrier sense multiple access with collision avoidance (CSMA/CA) to access the medium. When multiple end nodes compete to get access to the medium, unreliability is introduced into the system. In the beacon mode, because of the slotted CSMA access of sixteen equally spaced time slots for communication, there is a restriction of the size of a time slot and thus, the high throughput requirement of the system is not met. The solution proposed in the thesis project is to develop a custom time slot system in the non-beacon mode, where each end node is granted a reserved time slot of a specific length as required by the end node. There is a timer mechanism which makes sure that the time slots for each device maintain the time limit on the time slot, on the side of the main master/coordinator of the network and on the side of the end node. The protocol for an end node to join a personal area network (PAN) is called as the association process. The association process enables the end node to be a part of a PAN to exchange its sensor data. Traditionally, in IEEE 802.15.4, the end nodes scan the sixteen IEEE 802.15.4 channels and when an appropriate coordinator is found, the end node initiates the association process with the coordinator. The solution proposed for the formation of the network by the association process is to use two different technologies. The end nodes and the coordinator exchange information using near field communication (NFC) technology by a simple tapping mechanism. The end node has an active NFC tag while the coordinator has an NFC reader. During the tap between the two devices, first the coordinator reads the end node data from the active tag. This data is required to form the custom time slot. Next the coordinator writes all association information into the active tag. After the NFC data exchange is done, the end node initiates the traditional IEEE 802.15.4 association protocol to join the coordinator’s PAN. Similarly after seven end nodes are associated to the coordinator, the network begins to function. All the end nodes communicate their data to the coordinator. The coordinator collects all the sensor data from the seven end nodes and may send the cumulative sensor data to the backend database servers which may be viewed by the medical authorities, this part is not included in the current version of the project. Several tests are run on this system to evaluate the requirements of latency, throughput and quality of service with two different ranges of 20cm and 250cm. The latency of association between the coordinator and end node is 632ms. The required throughput is met by the network. The packet delivery rate of the system is always above 99%. The graphs for packet delivery rates for all the sensors with a range of 20cm and 250 cm are shown in the appendices. The probabilities for the packet delivery rates greater than 90%, 99%, 99.9% and 99.99% are also graphically shown using a normal distribution in the appendices.
84

Optimisation de l’extraction des caroténoïdes à partir du persimmon (Diospyros kaki L.), de l’abricot (Prunus armeniaca L.) et de la pêche (Prunus persica L.) : étude photophysique en vue d’une application en thérapie photodynamique (PDT) / Optimization of carotenoids extraction from persimmon (Diospyros kaki L.), apricot (Prunus armeniaca L.) and peach (Prunus persica L.) : Photophysical study for photodynamic therapy (PDT) application

Zaghdoudi, Khalil 17 December 2015 (has links)
La thérapie photodynamique (PDT) est une technique utilisée cliniquement pour traiter certaines maladies de la peau, la dégénérescence maculaire liée à l’âge et certains types de cancer. Elle fait intervenir trois composants : une molécule photosensible ou photosensibilisateur (PS), la lumière et l’oxygène. Après administration du PS, celui-ci va se localiser plus ou moins sélectivement dans les zones tumorales où il est alors activé par irradiation lumineuse à une longueur d’onde et une puissance données. Ceci engendre la formation d’espèces réactives de l’oxygène (ROS) très réactives, dont l'oxygène singulet1 O2, qui entraînent la destruction des tissus tumoraux par nécrose ou apoptose. Afin d’améliorer la sélectivité du traitement, différentes pistes sont actuellement exploitées dont l’élaboration de « photodynamic molecular beacons » (PMB). Dans un PMB, le photosensibilisateur (PS) est associé via un peptide à un inhibiteur 1O2, appelé quencher. Ce quencher inhibe la formation d’1O2 tant que le composé n’a pas atteint sa cible. Une fois la zone cancéreuse atteinte, des enzymes spécifiques clivent le peptide, libérant ainsi le PS qui retrouve alors sa capacité à former de l’1O2. Trouver un couple PS/quencher adéquat reste un challenge en PDT. Les propriétés photophysiques particulières des caroténoïdes et leur aptitude à inhiber la production d’1O2 font de ces derniers des quenchers potentiellement utilisables pour l’élaboration de PMBs. Chez les plantes, les caroténoïdes (carotènes et xanthophylles) sont des pigments associés à la photosynthèse, qui ont deux rôles principaux : un rôle de collecteur de lumière et un rôle photoprotecteur en protégeant le(s) système(s) photosynthétique(s) contre les dommages photooxydatifs liés à une exposition trop intense à la lumière. Ceci s’opère, entre autre, via le cycle des xanthophylles. Cette aptitude à capter de l’énergie présente un intérêt potentiel à ne pas négliger dans la perspective de la conception de PMB utilisables en thérapie photodynamique. Dans le cadre de cette thèse en co-tutelle avec la Faculté des Sciences de Bizerte nous avons ciblé les caroténoïdes présents dans trois fruits produits en Tunisie à savoir les kakis (Diospyros kaki L.), les abricots (Prunus armeniaca L.) et les pêches (Prunus persica L.) connus pour leur richesse globale en ces pigments. Divers procédés d’extractions ont été étudiés : (i) L’extraction de type Soxhlet par solvants organiques à pression atmosphérique, utilisée comme référence, (ii) l'extraction accélérée par solvant organique (ASE : Accelerated solvent Extraction) effectuée sous pression, enfin (iii) l'extraction par CO2 supercritique avec l’éthanol comme cosolvant. Pour ces deux derniers procédés, une approche par plan d’expériences (surfaces de réponses) a été utilisée pour identifier les facteurs clé et les conditions optimales d’extractions de divers caroténoïdes (pression, température, débit, % de cosolvant, temps, nombre de cycles). L'analyse par chromatographie liquide à haute performance couplée à la détection UV-Visible et à la spectrométrie de masse a ensuite permis l'identification et la quantification des caroténoïdes présents dans les extraits obtenus, permettant ainsi de comparer les profils caroténoïdiques propres à chaque fruit et les performances de chaque procédé d’extraction. Cette étude ayant révélé un profil caroténoïdique particulièrement intéressant chez le kaki par rapport aux autres fruits, une extraction et une purification des caroténoïdes de ce fruit par chromatographie liquide haute pression préparative a ensuite été effectuée afin de disposer d’une quantité suffisante de chaque caroténoïde, et parfois de leurs isomères conformationnels, en vue de l’étude de leurs propriétés photophysiques (absorption, émission de fluorescence, inhibition d’1O2) et de l’évaluation de leur intérêt potentiel en tant que quencher d’1O2 dans un édifice de type PMB / Photodynamic therapy (PDT) is a clinically used technique for treating skin diseases, age-relatedmacular degeneration but mainly some types of cancer. PDT involves three components: a photosensitive molecule named photosensitizer (PS), light and oxygen. After administration of the PS, this one will be located more or less selectively in tumoral regions where it is activated by light irradiation at appropriate wavelength and power. This leads to the formation of highly reactive and cytotoxic reactive oxygen species (ROS), especially singlet oxygen, resulting in the destruction of the tumor by necrosis or apoptosis. To improve the treatment selectivity, different strategies are being exploited, one of which is the development of "photodynamic molecular beacons" (PMB). In PMB the photosensitizer is linked via a peptide to an inhibitor of 1O2 (quencher). This quencher inhibits the formation of 1O2 as long as the compound has not reached its target, namely cancer cells. In order to inhibit the toxicity of the PS in non-target cells and restore toxicity only close to the biological target, it is necessary to find an adequate PS/quencher couple. This remains a challenge for PDT. Carotenoids are interesting candidates due to their specific photophysical properties and ability to inhibit 1O2, which makes them potential quenchers for building PMBs. In plants, carotenoids (carotenes and xanthophylls) are pigments involved in the photosynthesis, in which they play two main roles: a light collecting role and a protecting role by preserving the photosynthetic systems against photoxydative damages induced by a too intense light exposure. This protection can for instance occur via the well-known xanthophylls cycle. This capacity to catch energy presents a potential interest that should not be neglected in the framework of the design of PMBs usable in photodynamic therapy. Within the framework as part of this PhD thesis in Cotutelle with the Faculty of Sciences of Bizerte, we focused on carotenoids from three fruits produced in Tunisia: persimmon (Diospyros kaki L.), apricot (Prunus armeniaca L.) and peache (Prunus persica L.), known for their global richness in these natural pigments. Three extraction processes were investigated: (i) the Soxhlet extraction based on the use of organic solvent at atmospheric pressure and used as reference, (ii) the accelerated solvent extraction (ASE) using organic solvent under high pressure, and (iii) the supercritical fluid extraction (SFE) using supercritical CO2 and ethanol as cosolvent. For these two last processes, a design of experiments (Surface Response Design) was used to identify the key factors and optimal extraction conditions of various carotenoids (pressure, temperature, flow, % cosolvent, time, number of cycles). Then, HPLC-PDA coupled with mass spectrometry (MS) enabled the identification and quantification of carotenoids from the extracts. Thus it was possible to compare the profiles in carotenoids content from each fruit as well as the performances of each extraction process. This study showed that the carotenoidic profile in the persimmon was the most interesting as compared to the profiles in the two other fruits. Extraction and purification of the carotenoids from persimmon by preparative high pressure liquid chromatography were then performed in order to have a sufficient amount of each carotenoid and sometimes of their conformational isomers. We finally performed a study of their photophysical properties (absorption, fluorescence emission, 1O2 inhibition) in order to evaluate their potential as 1O2 quencher in molecular construction such as a PMB
85

Integrace operačních středisek v rámci Krajského ředitelství policie Jihočeského kraje / Integration of operations centres in the South Regional Police Headquarters Region

SVĚTLÍK, Jan January 2012 (has links)
As the topic of my diploma work I chose the issue of integration of operation centers in the jurisdiction of the Directory of Czech Police of the South Bohemian Region. This topic was chosen with regard to my job in the police of the Czech Republic and also with the assumption to assess the current state of the operation management in the jurisdiction of the Directory of Czech Police of the South Bohemian Region and compare it with the newly proposed integrated centre which should be created within the framework of integration of existing regional operation centres, evaluation of communication of operations centres within the framework of the integrated rescue system and within the framework of the police of the Czech Republic itself at different levels of operation management. The aim of my thesis is to describe the current state of workplaces of operation centers of the police of the Czech Republic and to assess their integration into a single operation center in the teritory of the South Bohemian region. I analyze the situation from the viewpoint of conduct, management and personal security and I assess material-technical security. Last but not least it's about confirming or refuting the hypothesis that was formulated before i started the thesis. This thesis stems particularly from internal act of conduct of the police of the Czech Republic and from the current legislation. Aims of my work are summarized in the capter Discussion which was preceded by description of the current state of operation centers and their function in the framework of operation conduct. Comparing the current and the suggested solution from the viewpoint of conduct, management, personal security, economic and material-technical security and physical integration. The formulation given by the hypothesis was confirmed based on the comparison carried out in the study of the current state and the prepared state, and seems to be effective. Because of the introduced measures that are realized by integration of the current operation centers into one, the effectivity will be increased.
86

Cross-platform Mobile Development and Internet of Things : Developing a cross-platform mobile application using web technologies to interact with smart things

Anton, Andersson, Runbert, Johan January 2015 (has links)
Today more and more objects in our daily lives are getting connected to the Internet. This phenomenon is called the Internet of Things and is a way for physical things such as cars, buildings or even bus stations to get access and communicate with other objects using the Internet. The problem is that for every Internet of Things device, an application is often needed in order to communicate with these devices. Developing mobile applications in a separate programming language for each operating system can be an expensive and time consuming task. In this thesis, we implement and evaluate a cross-platform mobile solution for users to interact with smart things using the advantages of web technologies. To compare previous findings in this area, two literature reviews has been performed to find out which is the state of the art on cross-platform mobile development frameworks and smart-things technologies used for interacting with physical objects. The result is a mobile application developed using PhoneGap and jQuery Mobile that interacts with iBeacons, where students inside a university building can get directions and schedules for different rooms. The application received good results from a couple of usability studies, and performed well when measuring its performance. The outcome shows that web technologies that exist today are a viable solution to native mobile applications in terms of interacting with smart things such as tagging technologies.
87

Data Fusion Based Physical Layer Protocols for Cognitive Radio Applications

Venugopalakrishna, Y R January 2016 (has links) (PDF)
This thesis proposes and analyzes data fusion algorithms that operate on the physical layer of a wireless sensor network, in the context of three applications of cognitive radios: 1. Cooperative spectrum sensing via binary consensus; 2. Multiple transmitter localization and communication footprint identification; 3.Target self-localization using beacon nodes. For the first application, a co-phasing based data combining scheme is studied under imperfect channel knowledge. The evolution of network consensus state is modeled as a Markov chain, and the average transition probability matrix is derived. Using this, the average hitting time and average consensus duration are obtained, which are used to determine and optimize the performance of the consensus procedure. Second, using the fact that a typical communication footprint map admits a sparse representation, two novel compressed sensing based schemes are proposed to construct the map using 1-bit decisions from sensors deployed in a geographical area. The number of transmitters is determined using the K-means algorithm and a circular fitting technique, and a design procedure is proposed to determine the power thresholds for signal detection at sensors. Third, an algorithm is proposed for self-localization of a target node using power measurements from beacon nodes transmitting from known locations. The geographical area is overlaid with a virtual grid, and the problem is treated as one of testing overlapping subsets of grid cells for the presence of the target node. The column matching algorithm from group testing literature is considered for devising the target localization algorithm. The average probability of localizing the target within a grid cell is derived using the tools from Poisson point processes and order statistics. This quantity is used to determine the minimum required node density to localize the target within a grid cell with high probability. The performance of all the proposed algorithms is illustrated through Monte Carlo simulations.
88

John R. Rice, <i>The Sword of the Lord</i>, and the Fundamentalist Conversation: Comparisons with J. Frank Norris's <i>The Fundamentalist</i> and Carl McIntire's <i>The Christian Beacon</i>

Smith, Robin L. 16 December 2013 (has links)
No description available.
89

Selenium redox cycling; isolation and characterization of a stimulatory component from tissue of loblolly pine for multiplication of somatic embryos; development of an assay to measure l-phenylalanine concentration in blood plasma

DeSilva, Veronica 25 June 2007 (has links)
Exogenously supplied organoselenium compounds, capable of propagating a selenium redox cycle, were shown to supplement natural cellular defenses against oxidants generated during biological activity. Phenylaminoalkyl selenides were developed in our laboratory as novel substrate analogs for the enzyme dopamine beta-monooxygenase. Recently, phenylaminoalkyl selenides were found to protect plasmid DNA and Molecular beacons from oxoperoxynitrate – mediated damage by scavenging this oxidant and forming the corresponding selenoxides as the sole selenium – containing products. Rate constants were determined for the reactions of the phenylaminoalkyl selenoxides with GSH at physiological pH and 25 degrees C. The kinetic data obtained in current and previous research was subsequently used in a MatLab simulation, which showed the feasibility of selenium redox cycling by GSH in the presence of a cellular oxidant, oxoperoxynitrate. Loblolly pine (LP, Pinus taeda) is the primary commercial species in southern forests covering 11.7 million hectares. Somatic embryogenesis (SE) is an effective technique to implement production of high value genotypes of LP. SE is a multi-step process, which includes initiation of somatic embryo (SME) growth from tree tissue, maintenance and multiplication of early stage SMEs and the maturation / germination phase. In this work, we isolated a substance from stage 2 or 3 LP female gametophyte (FG) tissue that stimulates early stage SME growth, and characterized this substance as citric acid on the basis of 1H NMR and mass spectrometry. We then demonstrated that topical application of citric acid to SMEs stimulates embryo colony growth at p = 0.05 for 3 of the 5 genotypes tested. Phenylketonuria (PKU) is an autosomal recessive disorder caused by an impaired conversion of L-phenylalanine (L-Phe) to L-tyrosine (L-Tyr). A novel assay based on enzymatic - colorimetric methodology (ECA) was developed in order to detect elevated concentrations of L-Phe in undeproteinized plasma of PKU patients via continuous spectrophotometric detection. We report here that L-Phe concentrations in undeproteinized plasma measured using our ECA were comparable to those determined on an amino acid analyzer based on Pearson correlation coefficients and a Bland and Altman comparison.

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