Today’s society is one where technological advances are made daily, which increases the need to stop and assess the risks against users’ integrity when integrating new technology in contemporary systems all the greater. We have taken two technologies, Near Field Communication and Certified Wireless USB, whose envisioned area of use is to be integrated into mobile phones, and evaluated what security threats are revealed for the respective technologies. The threats against security have been identified through research of the standards and existing reports for each technology. Practical experiments have not been conducted on account of us not having access to any equipment to run such trials. The result of our studies is indecisive; pitched against Certified Wireless USB’s rigorous and robust security measures, implemented on hardware level, Near Field Communication’s lack of any such security implementations shines all the brighter. The real difference can be traced to the philosophy behind the technologies – Certified Wireless USB can be perceived as a complete product, while Near Field Communication bears more resemblance to a tool. In order to safely use a tool, knowledge about its use is required, thus in order to securely use Near Field Communication we propose two solutions; secure channel and secure identification, which developers can implement on a software level. Furthermore, we suggest that the implementation of security should be based on an incremental model where the security measures are scaled up in direct correlation with the sensitivity of the information managed. Our results imply that Near Field Communication does not have the inherent security that it should have in order to be safely and securely integrated into any system as it is. Therefore, measures have to be taken in order to implement this technology securely on a software level. For Certified Wireless USB it implies that nothing further is needed to achieve a secure implementation as the only weakness it displays is against Side Channel attacks, which are so complicated (and require direct access to the system) that we have deemed them unlikely to be attempted.

The last few years has witnessed a fast growth in technological advancement which has led to the development of several consumer electronic devices for different purposes or functionalities. For convenience and efficiency, there is the need to bring together all the different functionalities of these devices into a single multipurpose device such as mobile phone with the help of NFC (near field communication) technology. The need for NFC technology in mobile devices is fast gaining popularity in some countries, especially with the successes recorded in some of the NFC pilot projects. The NFC enabled mobile device is very intuitive; works with already existing infrastructures (i.e. ISO/IEC 14443 smartcards and it readers), allows for multiple applications, has a high level of security and comes with unique and attractive features, such as the ability to serve as both reader and writer modes, etc. NFC standards are specified by NFC Forum and it has a well organised ecosystem. This thesis is focused on the potentials of NFC and how it is used as a multipurpose device.

The meeting and conference industry is very varied, and conference designers strive to optimise the resources used during an event or conference. During several years of working in the conference and meeting industry the author found that some tasks associated with meetings and conferences are still handled manually. It was from the experience of these sometimes labour-intensive tasks that the idea sprung to introduce computer support. This thesis describes the development of a prototype in a mobile environment using Near Field Communication (NFC) as an identification token for an attendee at a conference or meeting. The conference centre where the conference and meeting scenario incorporated in the developed prototype is gathered from the author’s current place of work. As the prototype is developed as proof-of-concept it is not complete and needs to be developed further in order to be of use for a conference designer. The gain in reduced work can in some cases be quite intuitive, and in some other cases needs to be analysed. During the development of the prototype the author gained new knowledge in how mobile operating systems (OS) can differ compared to developing for OS aimed for stationary computers. One key difference was that the OS could at any time close or pause the application in order to free or save resources, such as memory or power, this behaviour needs to be managed and taken into consideration when developing for mobile OS. The author also learned how to use NFC and develop applications using NFC with an attendee-driven approach, which is important as the meeting industry strives to reduce the use of resources by making it more attendee-driven. The main idea behind the attendee-driven approach is to shift the tasks that are normally handled by the arranger of the conference, over to the conference attendee, e.g, the conference attendee books his or her lecture online, reducing the need of staff at a reservation call center.

Utgångspunkten för denna uppsats är en förstudie om den trådlösa tekniken Near Field Communication (NFC), som vi författare genomförde via en enkät. Några av svaren på enkäten som berörde ämnet riskbeteende fick oss att undra varför respondenter svarade som de gjorde på vissa frågor, då detta kunde innebära att de tog en risk med personlig information. Detta ledde till att vi ville ta reda på varför och till vilken gräns personer är villiga att ta risker med ny teknik, men även vilka variabler som spelar in i deras beslut att använda eller inte använda ny teknik. Vårt tillvägagångssätt är en litteraturstudie för att förstå vad som menas med användbarhet, riskbeteende och pålitlighet samt hur dessa hänger ihop. Efter att vi bildat oss en uppfattning om dessa och fördjupat oss lite mer inom ämnena, så genomförde vi intervjuer för att se hur den information vi forskat fram förhöll sig till våra respondenter. Urvalet av de personer som intervjuades har varit ”bekvämlighetsurval”, alltså personer i vår närhet.  Resultatet pekar på att det finns en hel del förarbete att genomföra innan man lanserar ny teknik. Dessutom har upplevd pålitlighet till företaget stor betydelse. För att många personer ska ta till sig ny teknik krävs det information och en del tillit till företaget i fråga, detta för att personen ens ska börja använda tekniken.

Les travaux de thèse sont axés sur le développement de nouvelles techniques de caractérisation basées sur la variation de la réponse d’un résonateur, réponse modifiée par les propriétés diélectriques ou métalliques d’un matériau sous test. La première méthode utilise la microscopie microonde en champ proche pour la caractérisation résonante et non destructive de matériaux diélectriques dans la bande ISM (2,45 GHz).Celle-ci permet de déterminer les propriétés électromagnétiques (permittivité relative, tangente de pertes) des échantillons diélectriques solides de faible volumepar rapport à la longueur d’onde de mesure, et cela sans aucun traitement préalable. La connaissance de ces paramètres est essentielle pour fournir des informations critiques nécessaires pour la conception, la modélisation et la fabrication de circuits microondes. Une deuxième approche vise l’étude et le développement d’un nouveau capteur à base de céramique, économique, sensible, et pouvant s’intégrer dans un système sans fil pour la détection et la caractérisation du degré de corrosion. Ces nouveaux capteurs fournissent des informations sur l'état de l'équipement opérationnel d’une structure cible afin d'assurer la sécurité de cette dernière et par conséquent celle de leurs utilisateurs. Pour ces deux axes d’études, des simulations sur des logiciels de calcul électromagnétique ont été effectuées puis validées par des mesures expérimentales. / This Ph. D thesis focuses on the development of new characterization techniques of dielectric and metallic materials in the ISM band (2.45 GHz). The first proposed method is based on non-destructive near field microave microscopy. This technique allows the determination of the electromagnetic properties (permittivity, loss tangent) of solid dielectric samples of small volume without prior treatment. The knowledge of these parameters is essential to provide critical information needed for accurately designing, modeling and manufacturing microwave circuits. A second study focuses on the development of a new, ceramic based, sensitive and economic sensor that can be integrated in a wireless system for the detection and characterization of the corrosion evolution. These new sensors provide information about the state of the operational equipment of the target structure in order to ensure the safety of these structures and therefore that of their users. In these two studies, simulations on electromagnetic calculation software have been performed and validated by experimental measurements.

Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(工学) / 甲第14871号 / 工博第3139号 / 新制||工||1470(附属図書館) / 27293 / UT51-2009-K667 / 京都大学大学院工学研究科高分子化学専攻 / (主査)教授 伊藤 紳三郎, 教授 長谷川 博一, 教授 金谷 利治 / 学位規則第4条第1項該当

M.Com. (Informatics) / This research has the aim of creating a low-cost, contactless, micro-payment framework to support micro-payments for the informal taxi industry in South Africa. The informal taxi industry is a prime example of an industry that needs simple and effective payments for low-cost services where the primary medium of payment is currently cash. Challenges of currently used are the security of cash, the difficulty for the taxi driver to collect cash, and the auditability of cash from the perspective of the taxi owner. Furthermore, the taxi owner does not know the routes the taxi travels or the petrol that is used by the taxi. Micro-payment transaction volumes are rapidly increasing due to consumer need for simple and effective payments for low-cost items and services. Micro-payment technologies are rapidly growing in popularity and demand, prompting the need for financial institutions to consider investment in the technology. Contactless technology, specifically near-field communication (NFC), is contributing to the exponential growth of micro-payments. Increasingly, consumers are not required to enter security information in order to perform transactions. By bringing a compatible card within range of a suitable reader, a transaction takes place with immediate effect, with little or no involvement from payment providers and financial institutions. Complementary wireless technologies such as GPS enable a multitude of applications by offering positional and speed information. Combining GPS technology with NFC enables contactless positional payment information to be accessible, to present a unique micro-payment concept. This dissertation presents M-Thinta, a low-cost contactless micro-payment model. The M-Thinta prototype demonstrates the real-world operation of the M-Thinta model. The prototype demonstrates that it is possible to create a functional low-cost, contactless micro-payment platform by combining a number of standard low-cost components.

So often in astronomy, an object is not considered for its individual merits, but for what we may learn from its properties regarding some larger population. The existence of dark matter is a prime example of this; we cannot see it directly but we can infer its presence by noting its effects on the stars orbiting within its potential. This thesis describes how various sets of tracer populations can be used to probe the properties of a variety of galaxies in the Local Group. I begin by describing the extraction of a variable catalogue from the Sloan Digital Sky Survey Stripe 82 dataset and then use the catalogue to select a high-quality set of RR Lyrae stars. Analysing the distribution of the RR Lyraes reveals three significant substructures in the Milky Way halo: the Hercules-Aquila Cloud and the Sagittarius Stream, which were already known to exist, and the Pisces Overdensity, which was previously undetected. It is a faint, extended structure found at ~80 kpc and is of unknown origin. Altogether, I find that nearly 80% of the RR Lyraes are associated with substructures, consistent with the theory that galaxy halos are predominantly, or even entirely, made up from disrupted satellites. I also investigate the density distribution of RR Lyraes in the halo, finding that it is best fit by a broken-power-law model, in good agreement with previous work. I go on to develop a set of tracer mass estimators that build on previous work which make use of actual (and not projected) distance and proper motion data, reflecting the amount and quality of data now available to us. I show that proper motion data is, in theory, very useful and can greatly increase the accuracy of the mass estimates; in practice, however, current analysis is hampered by the large errors inherent in the proper motion data. The results are also subject to mass-anisotropy degeneracy, which current data is not yet able to break. Nevertheless, I am able to estimate the mass of the Milky Way to be M = 2.7 ± 0.5 x 10¹² Msun and the mass of M31 to be M = 1.5 ± 0.4 x 10¹² Msun. Andromeda XII and Andromeda XIV are two M31 satellites that have been dubbed 'extreme' and are thought to be on first infall into the M31 system. I modify the classical Timing Argument so that it can be applied to two external galaxies and then apply it to M31 and each of And XII and And XIV in turn to investigate the properties of their orbits. I then run a series of Monte Carlo simulations to investigate how likely such satellites are to exist and conclude that they are not as unusual as previously believed. Finally, I discuss three upcoming wide-field, all-sky surveys and their implications for the future of the study of the Local Group.

Cette thèse s'inscrit dans un projet plus vaste, utilisant les propriétés plasmoniques de systèmes colloïdaux pour développer des guides d’onde à l'échelle submicrométrique. La plasmonique exploite les oscillations collectives des électrons libres à la surface des métaux nobles, excités par une lumière incidente. Les guides d’onde plasmoniques fabriqués par lithographie ont montré un potentiel pour le confinement et le guidage de l'énergie. En revanche, leur polycristallinité induit une dissipation optique. Notre approche consiste à exploiter les plasmons localisés à la surface de nano-objets colloïdaux et monocristallins. Les simulations, au même titre que les expériences, ont confirmé que la structure et l'organisation de ces objets engendraient un confinement et une exaltation du champ proche optique dans leur voisinage. Contrairement aux études en champ lointain, la caractérisation du confinement du champ proche produit par ce type de structures, de faibles tailles, présente plusieurs défis. Dans un premier temps, il est nécessaire de synthétiser les objets. Nous avons choisi d'étudier des particules sphériques d'or assemblées en réseaux de chaînes, puis des nanobâtonnets et des nanoprismes d'or. Le second défi a résidé dans l'organisation et le dépôt des réseaux de chaînes sur un substrat adéquat. Des réseaux étendus monocouches de chaînes monoparticulaires ont été obtenus après dépôt sur un substrat préalablement immergé dans une solution alcaline. Enfin nous avons caractérisé le champ proche optique au voisinage de ces colloïdes. Nous avons appliqué une méthode indirecte : la photomigration moléculaire, pour imager le champ proche optique avec une résolution spatiale latérale d'environ 50 nm. Celle-ci repose sur les propriétés d'un photochrome, qui se déplace sous l'effet d'une excitation lumineuse. Une caractérisation topographique par AFM, avant et après excitation, permet alors de cartographier l'intensité du champ proche. Un déplacement du film, uniquement au niveau des structures et suivant le gradient du champ, a été observé. Nous avons complété cette étude en utilisant deux techniques en "champ lointain", basées sur le balayage "pixel par pixel" d'une "sonde optique virtuelle". La photoluminescence à deux photons (TPL) a mis en évidence la possibilité de confiner ou d'étendre le signal suivant l'organisation des objets. Par ailleurs, l'enregistrement de cartes de température par la technique d'anisotropie de polarisation de fluorescence a démontré l'intérêt des réseaux réticulés de particules, comme sources de chaleur localisées en surface / This thesis is part of a larger project which uses plasmonic properties of colloidal systems to develop and conceive new submicron scale waveguides. Plasmonics exploits the collective oscillations of free electrons on noble metal surfaces, excited by incident light. Plasmonic waveguides made by lithography have shown potential for the confinement and guiding of light energy. On the other hand, their polycristallinity induces an optical dissipation that limits the propagation length. Our approach consists in using localized plasmons on colloidal and monocrystalline nano-object deposited on dielectric surfaces. Simulations, as well as experiments, have confirmed that the structure and organization of such objects generate both a confinement and an enhancement of the optical near field intensity in their vicinity. The characterization of the near field confinement near tiny plasmonic self-assembled structures presents several difficulties. First, it was necessary to synthesize objects and assemble them into networks, in coplanar geometry. Extended monolayer networks of monoparticle chains were obtained after deposition on a substrate previously immersed in an alkaline solution. In a second step, we have characterized the optical near-field around the colloids. We have applied molecular photomigration to image the near-field with a 50nm spatial resolution. This phenomenon relies on the molecular movement of photochromic films induced under light excitation. An AFM topographic characterization, before and after illumination, allows then to map the near-field intensity. A film migration, only around the object and along the field gradient, has been observed. Finally, we completed this study by using two "far field" techniques, based on "pixel by pixel" scanning of an "optical virtual probe". The two photons photoluminescence (TPL) has shown the possibility to confine or expand the signal, depending on object organization. The recording of map temperature by fluorescence polarisation anisotropy has demonstrated the interest of particle networks as localised heat sources

Mon travail de thèse présenté dans ce mémoire a démarré un nouvel axe de recherche au sein du laboratoire Interdisciplinaire Carnot de Bourgogne, et s'inscrit dans le programme "Dispositifs pour le traitement de l'information" du Labex ACTION. Ce consortium de recherche vise l'optimisation de toutes les étapes d'un système de traitement d'information, en s'appuyant sur des matériaux nano-structurés et sur des fonctionnalités non-linéaires. Dans ce contexte, cette thèse relève de la génération de signaux optiques dans le proche infrarouge, puisque l'objectif principal est d'hybrider la photonique intégrée à l'optique des LASER en cavité fibrée. Ces LASER innovants hybridant photonique et optique fibrée offrent, de par leur conception, de nombreux avantages particulièrement recherchés dans le domaine des télécommunications, comme par exemple un taux de répétition élevé, supérieur à la centaine de gigahertz, et des impulsions ultracourtes, de l'ordre de la centaine de femtosecondes.L'élément fondamental de l'approche développée durant ma thèse réside dans l'utilisation de micro-résonateurs gravés sur puce. Le matériau constituant ces structures est le siège de phénomènes non-linéaires qu'il est possible d'exalter afin de générer de nouvelles fréquences. De plus, en insérant la microstructure dans une cavité LASER fibrée, elle peut assurer un verrouillage de mode et donc la génération d'impulsions. Le filtrage par mélange à quatre ondes est alors le mécanisme mis en jeu.Ainsi, pour mener à bien ce nouveau projet, un montage de caractérisation a été conçu. Ce dernier comporte un microscope en champ proche dans le but d'analyser le champ électromagnétique se propageant dans la structure gravée sur puce, et plus particulièrement la propagation non-linéaire des modes guidés. En outre, le développement et l'analyse de microstructures ont été réalisés afin d'optimiser les propriétés linéaires et non-linéaires souhaitées. Pour ce faire plusieurs matériaux tels que le silicium-sur-isolant, les verres de chalogénures et les nitrures de silicium ont été expérimentés au travers d'une trentaine d'échantillons.De surcroît des collaborations intra et inter-laboratoires donnent à ce sujet d'étude pluridisciplinaire une grande richesse. Elles ont permis la démonstration de LASER hybrides générant des impulsions avec un taux de répétition de 250 GHz, ainsi que d'imager par microscopie champ proche un élargissement spectral d'une octave dans un guide de nitrure de silicium replié en spirale. / My thesis work presented in this doctoral dissertation has started a new research axis within the Carnot Interdisciplinary Laboratory of Burgundy, and is part of the "Information processing devices" program of the Labex ACTION. This research consortium aims to optimize all the steps of an information processing system, using nano-structured materials and non-linear functionalities. In this context, this thesis focuses on the generation of optical signals in the near infrared, with the main objective of hybridizing integrated photonics with fiber laser cavities. These innovative hybrid LASERs offer, by design, many advantages that are particularly sought-after in the field of telecommunications, such as a high repetition rate, greater than 100 GHz, and ultra-short pulses, of the order of 100 fs.The fundamental element of the approach developed during my thesis is the use of on-chip fabricated micro-resonators. The material constituting these structures is the site of non-linear phenomena that can be exalted to generate new frequencies. In addition, by inserting the microstructure into a fiber LASER cavity, it can ensure mode locking and thus pulse generation. Filter driven-four wave mixing is then the mechanism involved.In order to successfully carry out this new project, a full characterization bench was designed. The latter includes a near-field microscope to analyze the electromagnetic field propagating in the on-chip fabricated structure, and more particularly the non-linear propagation of guided modes. In addition, the development and analysis of microstructures were carried out in order to optimize the desired linear and non-linear properties. To do this, several materials such as silicon-on-insulator, chalcogenide glasses and silicon nitrides were tested on about thirty samples.In addition, intra- and inter-laboratory collaborations give this multidisciplinary study subject a great richness. They allowed the demonstration of hybrid LASERs generating pulses with a repetition rate of 250 GHz, as well as the imaging by near-field microscopy of an octave spectral widening in a spiral-folded silicon nitride guide.