Dissertations / Theses: 'Communication devices for peop'

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Teyssier, Marc. "Anthropomorphic devices for affective touch communication." Electronic Thesis or Diss., Institut polytechnique de Paris, 2020. http://www.theses.fr/2020IPPAT023.

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La communication des émotions est importante pour le bien-être physique et psychologique des humains.Nous communiquons nos émotions par la voix, mais aussi par le langage corporel comme les expressions faciales, la posture ou le toucher. Parmi ces éléments de communication non verbal, la modalité tactile joue un rôle particulier. Le toucher se produit dans des situations de co-localisation et implique un contact physique entre deux individus. Un contact tactile peut transmettre des émotions comme le fait de réconforter une personne en lui caressant doucement le bras.Les technologies et les dispositifs actuels utilisés pour la communication médiée ne sont pas conçus pour prendre en charge la communication affective par le toucher.Il est donc nécessaire d'avoir de nouvelles interfaces pour la médiation du toucher, à la fois pour détecter le toucher (pour remplacer la peau du récepteur) ainsi que pour transmettre le toucher (pour remplacer la main de l'émetteur).Pour explorer ce sujet, je prends inspiration du corps humain pour éclairer la conception de nouvelles interfaces. Je mets en avant l'utilisation des affordances anthropomorphiques pour concevoir des interfaces qui bénéficient de notre connaissance de l'interaction physique avec d'autres humains.Les affordances anthropomorphiques utilisent notre projection du fonctionnement et du comportement humains dans les attributs d'un objet, afin de suggérer les façons de l'utiliser.L'anthropomorphisme a reçu peu d'attention jusqu'à présent dans le domaine de l'Interaction Homme-Machine (IHM) ; son espace de conception est encore largement inexploré. Dans cette thèse, j'explore cet espace de conception et je me concentre sur l'augmentation des dispositifs mobiles et robotiques avec des capacités tactiles pour améliorer la transmission des émotions afin d'enrichir la communication sociale.Ceci soulève deux principaux problèmes de recherche, qui sont abordés dans cette thèse.Un premier problème est de définir le type de dispositif nécessaire pour réaliser un toucher. Actuellement, les dispositifs robotiques ne produisent pas un toucher proche de celui de l'humain.Dans la première partie de cette thèse, je me concentre sur la conception et l'implémentation d'interfaces capables de produire un toucher proche de celui de l'humain.Je mets en évidence différent facteurs qui composent le toucher humain et qui peuvent être reproduits par un dispositif robotique. J'évalue ensuite expérimentalement l'impact du toucher reproduit par un robot sur la perception des émotions.Je me suis appuyé sur ces premières résultats pour proposer Mobilimb, un bras robotique de petite taille qui peut être connecté à des appareils mobiles et qui peut toucher l'utilisateur.Un deuxième problème consiste à développer des interfaces capables de détecter le toucher. Mon approche est d'intégrer une peau artificielle, ressemblante à la peau humaine, sur des appareils existants.Je propose les prérequis pour reproduire de la peau humaine, ainsi qu'une méthode de fabrication pour reproduire ses propriétés visuelles, tactiles et kinesthésiques. Je propose ensuite une implémentation de peau artificielle qui peut être intégrée sur des dispositifs existants et qui peut détecter des gestes expressifs de toucher. Cette interface est ensuite utilisée pour explorer diverses applications et scénarios.En résumé, cette thèse contribue à la conception et à la compréhension des dispositifs anthropomorphiques pour la communication tactile affective. Je propose d'utiliser les affordances anthropomorphiques pour concevoir des interfaces.Pour aborder les questions de recherche de cette thèse, je me suis appuyé sur les caractéristiques biologiques humaines et les outils et méthodes de fabrication numérique. Les dispositifs présentés dans cette thèse proposent de nouvelles contributions techniques et empiriques autour de la détection et de la génération du toucher
Communicating emotions is important for human attachment and bonding as well as for physical and psychological well-being.We communicate emotions through voice, but also through body language such as facial expressions, posture or touch. Among all these nonverbal cues, the tactile modality plays a particular role. Touch happens in co-located situations and involves physical contact between two individuals. A touch contact can convey emotions such as comforting someone by gently stroking her arm.Current technologies and devices used for mediated communication are not designed to support affective touch communication.There is a need to have new interfaces to mediate touch, both to detect touch (to replace the receiver's skin) and to convey touch (to replace the emitter's hand).My approach takes inspiration from the human body to inform the design of new interfaces. I promote the use of anthropomorphic affordances to design interfaces that benefit from our knowledge of physical interaction with other humans.Anthropomorphic affordances project human functioning and behaviour to the attributes of an object to suggest ways of using it. However, anthropomorphism has received little attention so far in the field of Human-Computer Interaction; its design space is still largely unexplored. In this thesis, I explore this design space and focus on augmenting mobile and robotic devices with tactile capabilities to enhance the conveying of emotions to enrich social communication.This raises two main research problems addressed in this thesis.A first problem is to define the type of device needed to perform touch. Current actuated devices do not produce human-like touch.In the first part of this thesis, I focus on the design and implementation of interfaces capable of producing humanlike touch output.I highlight human touch factors that can be reproduced by an actuated device. I then experimentally evaluate the impact of humanlike device-initiated touch on the perception of emotions.Finally, I built on top of these findings to propose Mobilimb, a small-scale robotic arm that can be connected onto mobile devices and can touch the user.A second problem is to develop interfaces capable of detecting touch input. My approach is to integrate humanlike artificial skin onto existing devices.I propose requirements to replicate the human skin, and a fabrication method for reproducing its visual, tactile and kinaesthetic properties. I then propose an implementation of artificial skin that can be integrated onto existing devices and can sense expressive touch gestures. This interface is then used to explore possible scenarios and applications for mediated touch input.In summary, this thesis contributes to the design and understanding of anthropomorphic devices for affective touch communication. I propose to use anthropomorphic affordances to design interfaces.To address the research questions of this thesis, I built upon human biological characteristics and digital fabrication tools and methods. The devices presented in this thesis propose new technical and empirical contributions around touch detection and touch generation

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Rrustemaj, Etrur. "High speed communication devices using microstrips." Thesis, London South Bank University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.618665.

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Moores, John Demeritt. "All-optical soliton communication : devices and limitations." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/12212.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1994.
Includes bibliographical references (leaves 140-157).
by John Demeritt Moores.
Ph.D.

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Garg, Kamal. "Ultra Wideband Antennas for Personal Communication Devices." FIU Digital Commons, 2001. https://digitalcommons.fiu.edu/etd/3842.

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The objective of this thesis is to determine and analyze the characteristics of ultra wideband antennas for personal communication systems. For this purpose a diamond dipole antenna, an ultra wideband antenna designed by Time Domain Corp, is studied and various parameters, like Sil and the VSWR of the antenna are calculated. These parameters are determined by simulating the antenna using the XFDTD software and the MultiStrip program. The results thus obtained are validated by measurements on the network analyzer using the antenna model. A bowtie antenna with the same dimensions as the diamond dipole antenna is suggested and performance of these two antennas is compared. Subsequently a new geometry of bowtie antenna is suggested and the effect of varying the cone half angle on the VSWR and Sil parameters of the antenna is investigated. Further, a comparison is made between the new model of the bowtie antenna and the diamond dipole antenna. Towards the end, a new ultra wideband antenna using a bowtie is suggested.

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Hussain, Musharrif, and Sulman Mahmood. "Secure Software and Communication on Handheld Devices." Thesis, Blekinge Tekniska Högskola, Avdelningen för för interaktion och systemdesign, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-4348.

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Some applications on mobile handheld devices are involved in exchanging critical information e. g. sending positioning data of heavy-good vehicles as a basis for road toll. This information must not be accessed or modified illegitimately; however, there is the risk that can be accessed or modified by modifying the application or during communication of the handheld device with its counterpart. This thesis report investigates concepts to shelter software from modification and how the communication of these applications running on a handheld device over public mobile network can be made more secure. This work was performed by carefully identifying relevant literature and developing the concept that how a smart card can enhance the security of the software running on it particularly for handheld devices. It also discusses the issues and threats to smart cards. Furthermore it proposes a solution based on the specified scenario. The security of the software comprises on two layers; one layer is for analysis prevention, making it hard to understand the behaviour of the program both at static and dynamic levels. The other layer is responsible for verifying the integrity of the software to ensure that it is not modified. The software is installed on smart card which acts as an extra security layer. The communication relies on the security features of the public mobile network with some enhancement. In order to shelter the communication via public Internet, a border based VPN solution is deployed between the public mobile network and the remote server using the network assisted approach. This thesis will serve as basis for designing a secure communication path for Swedish road toll system.
Some applications on mobile handheld devices are involved in exchanging critical information e. g. sending positioning data of heavy-good vehicles as a basis for road toll. This information must not be accessed or modified illegitimately; however, there is the risk that can be accessed or modified by modifying the application or during communication of the handheld device with its counterpart. This thesis report investigates concepts to shelter software from modification and how the communication of these applications running on a handheld device over public mobile network can be made more secure. This work was performed by carefully identifying relevant literature and developing the concept that how a smart card can enhance the security of the software running on it particularly for handheld devices. It also discusses the issues and threats to smart cards. Furthermore it proposes a solution based on the specified scenario. The security of the software comprises on two layers; one layer is for analysis prevention, making it hard to understand the behaviour of the program both at static and dynamic levels. The other layer is responsible for verifying the integrity of the software to ensure that it is not modified. The software is installed on smart card which acts as an extra security layer. The communication relies on the security features of the public mobile network with some enhancement. In order to shelter the communication via public Internet, a border based VPN solution is deployed between the public mobile network and the remote server using the network assisted approach. This thesis will serve as basis for designing a secure communication path for Swedish road toll system.
+46 762733374 +46 737038932

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Xu, Yesheng. "Widget Communication Architecture with Emphasis on Mobile Devices." Thesis, Uppsala University, Department of Information Technology, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-98331.

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Small applications called widgets have been widely accepted on desktop and are on their way to be successful on mobile devices too. Widgets are usually managed by the widget runtime engines. This thesis considers that parts of the widget logic can be migrated to run in the network (for example, due to limited mobile device resources or other design reasons). In this case the mobile part of widget logic has to communicate with its network counterpart. It is also preferable to allow the mobile widgets to communicate with each other. Hence widget communication becomes an important aspect of the widget engine architecture. This thesis investigates the possibility of applying RESTful paradigm to the widget communication and proposes a corresponding architecture along with the prototype implementation.

Key Words: Widget, Mobile 2.0, Widget Communication, REST Framework, Mobile Web Server, Mobile Web Services.

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Mortimore, David Bryan. "Tapered fibre devices for optical fibre communication systems." Thesis, University of Essex, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.296363.

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Marks, Lori J., and M. L. McMurray. "Augmentative and Alternative Communication: A Continuum of Devices." Digital Commons @ East Tennessee State University, 2003. https://dc.etsu.edu/etsu-works/3551.

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Gooch, Daniel. "Designing communication devices for long distance dating relationships." Thesis, University of Bath, 2014. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.619151.

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This thesis investigates the design and use of communication technologies to support long distance dating relationships (LDDRs). We focus on using co-located behaviours that hold special relational meaning as the metaphor behind the design of devices to mediate between separated partners. Social Presence is used as the main theoretical construct through which support for LDDRs is addressed. Social Presence is a phenomenological concept which refers to “the degree of salience of the other person in the interaction and the consequent salience of the interpersonal relationship” [Short et al., 1976, p. 65]. An additional concept, Closeness, is also brought in to the design problem to account for the supportive role of communication technologies between moments of synchronous contact. This thesis proposes three main arguments. The first is that individual acts of communication, through feelings of Social Presence, have an impact on a couple’s feelings of Closeness towards one another. We explore possible connections between Social Presence and Closeness through a diary study. The results of the diary study also establish that the selection of communication media impacts feelings of Social Presence. Our second argument is that a number of design facets, explored throughout the thesis, could enhance the design of communication technologies for LDDRs by increasing feelings of Social Presence. An analysis of current literature informs the development of seven prototype devices based on hand-holding, hugging, sharing notes and pillow talk. Two interview studies explore people’s reactions to these devices. The findings from these studies are integrated into a design space which describes some of the design decisions that should be considered when creating behaviour-based devices which aim to support LDDRs. Our third argument is that devices based on co-located behaviours support LDDRs through engendering high levels of SP. This is investigated through five case studies using the devices we previously developed, showing that three of our devices are associated with particularly high levels of SP. They also provide insights about the design space facets, as realised in the devices, through using the devices within couples’ existing communication routines. The thesis concludes with a discussion of how the results of these studies are of relevance to researchers interested in supporting long distance dating relationships. Our investigation into Social Presence provides two main contributions; firstly it offers an understanding of how various factors (including relationship type and distance) affect feelings of SP. Secondly, it demonstrates that increasing feelings of Social Presence can have a longer-term impact on LDDRs through increasing their feelings of Closeness towards one another. This suggests that SP is suitable concept to try and support through the design of communication technologies. In addition to informing our discussion of our design space, the case studies within this thesis highlight that devices based on co-located behaviours can help support LDDRs. Given the dearth of devices based on this metaphor, we suggest that other researchers may be interested in extending these findings by exploring other behavioural metaphors. The design space proposed within this thesis offers two main contributions. Firstly, designers can use the design space to foster innovation when creating new designs. Design spaces result in a descriptive and exploratory tool for designers creating new innovations. Secondly, the comprehensive consideration of the various dimensions, especially regarding our consideration of existing communication technologies, provides researchers with a novel design-centric view over the state of the art.

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Kod, M. S. "Wireless powering and communication of implantable medical devices." Thesis, University of Liverpool, 2016. http://livrepository.liverpool.ac.uk/3004891/.

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Sun, Xu. "Hybrid Plasmonic Devices for Optical Communication and Sensing." Doctoral thesis, KTH, Optik och Fotonik, OFO, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-205974.

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Hybrid plasmonic (HP) waveguides, a multi-layer waveguide structure supporting a hybrid mode of surface plasmonics and Si photonics, is a compromise way to integrate plasmonic materials into Si or SOI platforms, which can guide optical waves of sub-wavelength size, and with relative low propagation loss. In this thesis, several HP waveguides and devices are developed for the purposes of optical communications and sensing. The single-slot HP ring resonator sensor with 2.6µm radius can give a quality factor (Q factor) of 1300 at the communication wavelength of 1.5µm with a device sensitivity of 102nm/RIU (refractive index unit). The Mach-Zehnder interferometer (MZI) with a 40µm double-slot HP waveguide has a device sensitivity around 474nm/RIU. The partly open silicon side-coupled double-slot HP ring resonator has a device sensitivity of 687.5nm/RIU, with a Q factor over 1000 after optimization. Further, an all-optical switching HP donut resonator with a photothermal plasmonic absorber is developed, utilizing the thermal expansion effect of silicon to shift the resonant peak of the HP resonator. The active area has a radius of 10µm to match the core size of a single-mode fiber. By applying 10mW power of the driving laser to the absorber, the resonator transmitted power can be changed by 15dB, with an average response time of 16µs. Using the same fabrication flow, and removing the oxide materials using hydrogen fluoride wet etching, a hollow HP waveguide is fabricated for liquid sensing applications. The experimentally demonstrated waveguide sensitivity is about 0.68, which is more than twice that of pure Si waveguide device. Microelectromechanical systems (MEMS) can also be integrated into vertical HP waveguides. By tuning the thickness of the air gap, over 20dB transmitted power change was experimentally demonstrated. This can be used for optical switching applications by either changing the absorption or phase of the HP devices.

QC 20170427

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Henry, Mark. "Sports Content Viewership Motivations Across Digital Devices." ScholarWorks, 2016. https://scholarworks.waldenu.edu/dissertations/2154.

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U.S. advertisers spent over $2 billion on sporting events in 2014 directing advertisements towards consumers through digital devices used such as televisions, computers, smartphones, and tablets. The purpose of this cross-sectional study was to identify motivation factors that predict the intention to view sports content on digital devices. Knowing such factors is important for advertisers to prioritize distribution channels. Uses and gratification theory formed the theoretical framework for the study. The methodology adapted a survey that encapsulated 9 motives. The research questions examined what motives influenced sports viewership, what motives predicted the intention to view specific sports content, and the differences in viewing intention across sports content types. Data were collected through a survey administered to a qualified random sample of U.S. respondents with 525 responses received. Data were analyzed using exploratory factor analysis to group the questions into motivation factors, multiple linear regression to determine the significance of these factors in predicting viewership intent, and nonparametric Friedman testing to determine what demographics influenced viewership. Findings included: (a) 8 factors explained 76% of the variance; (b) 8 motives were significant in predicting viewership intention, with Escape (Î² = .714) ranking the highest; and (c) younger viewers had a greater intent to consume content on digital devices other than television, with smartphones (M = .73) ranking the highest. Social change benefits include: (a) sports content providers and advertisers could target the right content and advertisement to maximize viewership retention and revenue, and (b) users could view their desired sports content on their chosen device.

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Wheeler, Patrick Sean. "Podscanning : audio microcontent and synchronous communication for mobile devices." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/57786.

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Thesis (S.M.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, February 2010.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 89-93).
Over the past decade, computationally powerful audio communication devices have become commonplace. Mobile devices have high storage capacity for digital audio, and smartphones or networked PDAs can be used to stream internet radio and download podcasts. However, applications that allow mobile devices to be used for synchronous communication (such as person-to-person audio interaction and listening to broadcast synchronous audio) are distinct from applications that allow stored audio playback. To demonstrate the benefits of more fluidity in mobile user interfaces between asynchronous audio and synchronous audio playback, I have implemented a new user interface approach - audio scanning - that merges these data types in a single user interface. A combined interface must solve two different research problems. Asynchronous messaging queues grow longer without constant user intervention. Synchronous audio, on the other hand, can be disruptive and transient. To address these problems, a timing heuristic is used in audio scanning to allow sporadic yet controlled delivery of organized audio bursts.
(cont.) To lessen the burden of user interaction with a graphical user interface on a mobile device, a single-button user interface allows control of audio presentation. Two exploratory systems implementing an audio scanning interface are described, allowing comparison to alternate audio systems and approaches. The first implementation, Hearplay, demonstrates the utility of audio scanning in a social audio appliance, designed to be available as an always-on system. The second implementation, Hearwell, demonstrates a use of audio scanning on a mobile phone to help individuals achieve wellness goals. The design and utility of the scanning interface is critiqued for both implementations.
by Patrick Sean Wheeler.
S.M.

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Mercier, Patrick Philip. "Communication and energy delivery architectures for personal medical devices." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/75642.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2012.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 219-232).
Advances in sensor technologies and integrated electronics are revolutionizing how humans access and receive healthcare. However, many envisioned wearable or implantable systems are not deployable in practice due to high energy consumption and anatomically-limited size constraints, necessitating large form-factors for external devices, or eventual surgical re-implantation procedures for in-vivo applications. Since communication and energy-management sub-systems often dominate the power budgets of personal biomedical devices, this thesis explores alternative usecases, system architectures, and circuit solutions to reduce their energy burden. For wearable applications, a system-on-chip is designed that both communicates and delivers power over an eTextiles network. The transmitter and receiver front-ends are at least an order of magnitude more efficient than conventional body-area networks. For implantable applications, two separate systems are proposed that avoid reimplantation requirements. The first system extracts energy from the endocochlear potential, an electrochemical gradient found naturally within the inner-ear of mammals, in order to power a wireless sensor. Since extractable energy levels are limited, novel sensing, communication, and energy management solutions are proposed that leverage duty-cycling to achieve enabling power consumptions that are at least an order of magnitude lower than previous work. Clinical measurements show the first system demonstrated to sustain itself with a mammalian-generated electrochemical potential operating as the only source of energy into the system. The second system leverages the essentially unlimited number of re-charge cycles offered by ultracapacitors. To ease patient usability, a rapid wireless capacitor charging architecture is proposed that employs a multi-tapped secondary inductive coil to provide charging times that are significantly faster than conventional approaches.
by Patrick Philip Mercier.
Ph.D.

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Lai, Yicheng. "Fibre-based devices for next generation photonics communication systems." Thesis, Aston University, 2003. http://publications.aston.ac.uk/8003/.

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The future broadband information network will undoubtedly integrate the mobility and flexibility of wireless access systems with the huge bandwidth capacity of photonics solutions to enable a communication system capable of handling the anticipated demand for interactive services. Towards wide coverage and low cost implementations of such broadband wireless photonics communication networks, various aspects of the enabling technologies are continuingly generating intense research interest. Among the core technologies, the optical generation and distribution of radio frequency signals over fibres, and the fibre optic signal processing of optical and radio frequency signals, have been the subjects for study in this thesis. Based on the intrinsic properties of single-mode optical fibres, and in conjunction with the concepts of optical fibre delay line filters and fibre Bragg gratings, a number of novel fibre-based devices, potentially suitable for applications in the future wireless photonics communication systems, have been realised. Special single-mode fibres, namely, the high birefringence (Hi-Bi) fibre and the Er/Yb doped fibre have been employed so as to exploit their merits to achieve practical and cost-effective all-fibre architectures. A number of fibre-based complex signal processors for optical and radio frequencies using novel Hi-Bi fibre delay line filter architectures have been illustrated. In particular, operations such as multichannel flattop bandpass filtering, simultaneous complementary outputs and bidirectional nonreciprocal wavelength interleaving, have been demonstrated. The proposed configurations featured greatly reduced environmental sensitivity typical of coherent fibre delay line filter schemes, reconfigurable transfer functions, negligible chromatic dispersions, and ease of implementation, not easily achievable based on other techniques. A number of unique fibre grating devices for signal filtering and fibre laser applications have been realised. The concept of the superimposed fibre Bragg gratings has been extended to non-uniform grating structures and into Hi-Bi fibres to achieve highly useful grating devices such as overwritten phase-shifted fibre grating structure and widely/narrowly spaced polarization-discriminating filters that are not limited by the intrinsic fibre properties. In terms of the-fibre-based optical millimetre wave transmitters, unique approaches based on fibre laser configurations have been proposed and demonstrated. The ability of the dual-mode distributed feedback (DFB) fibre lasers to generate high spectral purity, narrow linewidth heterodyne signals without complex feedback mechanisms has been illustrated. A novel co-located dual DFB fibre laser configuration, based on the proposed superimposed phase-shifted fibre grating structure, has been further realised with highly desired operation characteristics without the need for costly high frequency synthesizers and complex feedback controls. Lastly, a novel cavity mode condition monitoring and optimisation scheme for short length, linear-cavity fibre lasers has been proposed and achieved. Based on the concept and simplicity of the superimposed fibre laser cavities structure, in conjunction with feedback controls, enhanced output performances from the fibre lasers have been achieved. The importance of such cavity mode assessment and feedback control for optimised fibre laser output performance has been illustrated.

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Baalaji, Venkateshwaraiyer S. "Wireless tool kit for hand held devices." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2004. http://library.nps.navy.mil/uhtbin/hyperion/04Sept%5FBaalaji%5FCS.pdf.

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Jeffcote, Richard Grant. "An Investigation into the Monitoring of Pest Control Devices using Wireless Communication." Thesis, University of Canterbury. Engineering Management, 2013. http://hdl.handle.net/10092/7457.

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The monitoring of animal control devices (animal traps) in remote areas currently requires field workers to visit each device on a regular basis, which is costly and time consuming. Better monitoring practices could allow DOC to increase their trapping practices through reduced costs. Essentially, the aim of this paper is to reduce the number of man-hours, and hence resources, required to check each trap. An attempt will be made to use wireless communications to check the status of each trap, and hence decide whether or not it will need to be checked, bringing benefits of efficiency and cost savings to the Department of Conservation. It is recognised that the environment is very difficult for traditional wireless communications to operate reliably and therefore new methods or technologies were investigated for this application. A system operating at 27MHz using a modified pulse position modulation scheme was found to be an appropriate solution; however the success of wireless communications in pest control management is dependent upon the trapping location, patterns and terrain.

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Devi, M. K. Sowmia Agrawal Prathima. "Interface selection in multi-interface mobile devices." Auburn, Ala., 2006. http://repo.lib.auburn.edu/2006%20Summer/Theses/MYLAPORE_KRISHNA_8.pdf.

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Pochiraju, Sandhya. "Fabrication of Polymer Based Optical Devices for Communication and Sensing." UKnowledge, 2006. http://uknowledge.uky.edu/gradschool_theses/270.

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Polymer waveguides present a potentially low cost alternative to electronics in communication systems. Polymers offer relatively straightforward and economical fabrication when compared to conventional materials. In this study, a fabrication process for Bragg gratings in polymer waveguides was developed. Waveguides were designed using finite-element analysis, patterned via e-beam lithography, and a detailed fabrication method was developed. Surface-Plasmon Resonance (SPR) is a widely accepted method for biological and chemical sensing. Measurement of bulk refractive index changes and specific surface binding is a crucial part in any biosensing. Design and fabrication of a novel self-referencing SPR sensor is described and its functionality is tested.

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Ashford, Rain. "Responsive and emotive wearable technology : physiological data, devices and communication." Thesis, Goldsmiths College (University of London), 2018. http://research.gold.ac.uk/24005/.

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My research practice and thesis investigates how wearable technology can be used to create new forms of nonverbal communication. Using devices developed through my practice, I explore how physiological data can be drawn from the body, then visualised and broadcast. I examine the opinions and requirements of potential users and observers of this technology, through qualitative responses in interviews and surveys from focus groups and field tests. I have analysed the resulting data to extract preferences and concerns, plus the requirements for the functionality and aesthetics of these devices. I discuss the social and cultural aspects of wearing such devices, as well as the issues, including how privacy may be affected and the implications of recording personal data. I examine my practice in the context of the work of the communities and practitioners in the field, and introduce two new terms to label two sub-sections of wearable technology. These are ‘responsive wearables’ and ‘emotive wearables’, and they form part of the distinctive contribution that I make. Reflecting on the evolution of my practice has led to other contributions regarding the development of wearable technology. Through this, I identify and share the insights into the disciplines and processes required for the fusion of technology and design successfully to evolve electronics, code and materials into research prototypes. I conclude by discussing findings from my practice, research and studies with potential users of emotive wearables. I comment on the impact that physiologically sensing wearable technology has on aspects of social interaction for the individual as well as for the wider community. I open the discussion on future research by revealing two new examples of emotive wearables — the AnemoneStarHeart and the ThinkerBelle EEG Amplifying Dress — which have evolved from pinpointing specific areas of the focus group and field test feedback that I undertook.

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Abid, Abubakar. "Ingestible electronics without batteries : power and communication for gastroresident devices." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/107102.

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Thesis: M. Eng., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2016.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 77-80).
In this thesis, I introduce a novel ingestible electronic device designed to reside inside the stomach for weeks or longer with both wireless communication and wireless powering capabilities. The device is powered by a transmitter outside of the body via wireless power transfer through 5 to 6 cm of tissue, while keeping under specific absorption of radiation limits. Electromagnetic theory and microwave simulations identified the optimal region of operation for transmitting power through tissue as around 1 GHz. Small loop antennas fabricated to fit onto a circuit board the size of a pill capsule exhibited power transfer efficiencies of around -45 dB when tested ex vivo in pig stomach tissue. Choice of electronic components for rectification, sensing, and wireless communication are also discussed, as well as electrical and material characterization of an encapsulated device, to show that an end-to-end wireless ingestible electronic device is feasible for gastroresident applications.
by Abubakar Abid.
M. Eng.

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Futrakul, Nuttrapong. "Analysis of efficiency microwave power amplifier for personal communication devices." FIU Digital Commons, 2002. http://digitalcommons.fiu.edu/etd/3429.

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The primary purpose of this research was to study the power gain and efficiency of microwave power amplifier for personal communication devices by using simulation software. In the power amplifier circuit designs, the power gain and efficiency of power amplifier are significant factors. The Doherty configuration and matching components for both input and output of the system are the main techniques use for the thesis research. The Doherty configuration uses two transistors to optimize the total output gain. The matching technique provides the maximum gain at the target frequency. The individual stability consideration for transistors was calculated by MatLab script in order to meet the requirement for microwave circuit design. The simulation software, PUFF, was used as the simulation tool. The circuit simulation results were introduced at target frequency 2.1 GHz. The bandpass filter designs also integrated into the circuits in order to eliminate the frequencies outside the band.

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Sima, Chaotan. "Integrated planar Bragg grating devices for advanced optical communication systems." Thesis, University of Southampton, 2013. https://eprints.soton.ac.uk/359836/.

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This thesis presents theoretical and experimental studies of planar Bragg grating devices for all-optical signal processing. Bragg gratings offer a route to realise many systems for all-optical signal processing including photonic Hilbert transformers. The fabrication of Bragg gratings in a planar format allows monolithic integration with traditional planar components and micro-heaters to realise devices with desired performance. Photonic Hilbert transformers offer potential for a wide range of applications such as single-sideband modulation, and also provide operational bandwidths and speeds far beyond current electronic technologies. A series of experimental demonstrations of photonic Hilbert transformers based on apodised planar Bragg gratings with phase-shifts are presented. Devices implementing fractional order Hilbert transform are also investigated. Grating structures are synthesised to achieve improved spectral quality including the demonstration of devices with Terahertz bandwidths. A direct UV grating writing technique based on phase-controlled interferometry is proposed and demonstrated to fabricate arbitrary Bragg gratings in a silica-on-silicon platform. Electro-optic phase modulation of one beam in the interferometer is used to manipulate the fringe pattern and control the parameters of Bragg gratings and waveguides. Along with the unique micron-order writing spot, modulation linearity and translation consistency ensures the desired grating apodisation profile is achieved. Furthermore, the significant improvement in fringe control results in larger grating index contrast, enabling Terahertz bandwidth devices. Finally, the system utilising the phase controlled UV writing technique is applied to the inscription of fibre Bragg gratings. Various kinds of fibres are experimentally tested in the work. The small writing spot shows potential and significant capability to inscribe arbitrary Bragg gratings into fibre structures.

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Hashemi, SeyyedKamal. "Microwave devices and techniques for ultra-wideband (UWB) communication systems." Thesis, University of Essex, 2011. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.548599.

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Ovens, Kenneth Martin. "Digital forensic analysis of communication applications on Apple iOS devices." Thesis, Glasgow Caledonian University, 2017. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.743916.

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Azam, Sher. "Microwave Power Devices and Amplifiers for Radars and Communication Systems." Doctoral thesis, Linköpings universitet, Halvledarmaterial, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-19267.

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SiC MESFETs and GaN HEMTs posses an enormous potential in power amplifiers at microwave frequencies due to their wide bandgap features of high electric field strength, high electron saturation velocity and high operating temperature. The high power density combined with the comparably high impedance attainable by these devices also offers new possibilities for wideband power microwave systems. Similarly Si-LDMOS being low cost and lonely silicon based RF power transistor has great contributions especially in the communication sector. The focus of this thesis work is both device study and their application in different classes of power amplifiers. In the first part of our research work, we studied the performance of transistors in device simulation using physical transistor structure in Technology Computer Aided Design (TCAD). A comparison between the physical simulations and measured device characteristics has been carried out. We optimized GaN HEMT, Si-LDMOS and enhanced version of our previously fabricated and tested SiC MESFET transistor for enhanced RF and DC characteristics. For large signal AC performance we further extended the computational load pull (CLP) simulation technique to study the switching response of the power transistors. The beauty of our techniques is that, we need no lumped or distributive matching networks to study active device behavior in almost all major classes of power amplifiers. Using these techniques, we studied class A, AB, pulse input class-C and class-F switching response of SiC MESFET. We obtained maximum PAE of 78.3 % with power density of 2.5 W/mm for class C and 84 % for class F power amplifier at 500 MHz. The Si-LDMOS has a vital role and is a strong competitor to wideband gap semiconductor technology in communication sector. We also studied Si-LDMOS (transistor structure provided by Infineon Technologies at Kista, Stockholm) for improved DC and RF performance. The interface charges between the oxide and RESURF region are used not only to improve DC drain current and RF power, gain & efficiency but also enhance its operating frequency up to 4 GHz. In the second part of our research work, six single stage (using single transistor) power amplifiers have been designed, fabricated and characterized in three phases for applications in communications, Phased Array Radars and EW systems. In the first phase, two class AB power amplifiers are designed and fabricated. The first PA (26 W) is designed and fabricated at 200-500 MHz using SiC MESFET. Typical results for this PA at 60 V drain bias at 500 MHz are, 24.9 dB of power gain, 44.15 dBm output power (26 W) and 66 % PAE. The second PA is designed at 30-100 MHz using SiC MESFET. At 60 V drain bias Pmax is 46.7 dBm (~47 W) with a power gain of 21 dB. In the second phase, for performance comparison, three broadband class AB power amplifiers are designed and fabricated at 0.7-1.8 GHz using SiC MESFET and two different GaN HEMT technologies (GaN HEMT on SiC and GaN HEMT on Silicon substrate). The measured maximum output power for the SiC MESFET amplifier at a drain bias of Vd= 66 V at 700 MHz the Pmax was 42.2 dBm (~16.6 W) with a PAE of 34.4 %. The results for GaN HEMT on SiC amplifier are; maximum output power at Vd = 48 V is 40 dBm (~10 W), with a PAE of 34 % and a power gain above 10 dB. The maximum output power for GaN HEMT on Si amplifier is 42.5 dBm (~18 W) with a maximum PAE of 39 % and a gain of 19.5 dB. In the third phase, a high power single stage class E power amplifier is implemented with lumped elements at 0.89-1.02 GHz using Silicon GaN HEMT as an active device. The maximum drain efficiency (DE) and PAE of 67 and 65 % respectively is obtained with a maximum output power of 42.2 dBm (~ 17 W) and a maximum power gain of 15 dB.

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Kayayurt, Barış Tuğlular Tuğkan. "End-to-end security for mobile devices/." [s.l.]: [s.n.], 2004. http://library.iyte.edu.tr/tezler/master/bilgisayaryazilimi/T000492.pdf.

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Bershad, Brian Nathan. "High performance cross-address space communication /." Thesis, Connect to this title online; UW restricted, 1990. http://hdl.handle.net/1773/6939.

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Chek, Cho-hoi Michael, and 戚祖凱. "Coexistence techniques for heterogeneous mobile devices operating in uncoordinated radio spectrum." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2003. http://hub.hku.hk/bib/B29330725.

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Pierfederici, Eugenio. "Inferring the behaviour and security of networked devices via communication analysis." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/19418/.

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In the last years the number of devices connected to the Internet has been increasing exponentially and it has reached huge numbers, just days ago the RIPE Network Coordination Center announced it run out of IPv4 addresses. As a consequence, it's extremely complex to control what is happening on the network and what, or whom, a device is communicating with. We are losing control over many of our devices. It's becoming everyday more difficult to know what the device is doing and what is it sharing on the Internet. Luckily, in the last years the attention to security, privacy and awareness is ever increasing: the users pay more attention to what their devices are doing and care about it. While big software (like the operative systems and most mobile devices) make available an increasing number of tools to monitor the device traffic, some devices cannot be inspected or those same tools may be forged in a way that makes it impossible to detect some specific malicious behaviours. Until now every successful method to detect or filter the behaviour of the devices has been trying to only detect anomalies or manually lock some specific behaviours; this means nobody ever tried to understand at a discrete level of accuracy what the device does relying only on the analysis of the metadata of the traffic intercepted. That’s why in this thesis I defined a model able to detect the behaviour which is occurring on the device by the mere observation of its network traffic. In doing so, I first defined a model that takes the raw low-level information regarding the communications occurring, process them and return information about the high-level operations occurring on the device. I then built a demo that uses that model and demonstrates its feasibility. The data used are low-level information on the traffic without ever inspecting its payload. To improve the efficiency of the algorithm, I also use a form of Recurrent Neural Networks to finally infer the device behaviour.

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Odelius, Johan. "Communication quality : a conceptual approach focusing on classroom assistive listening devices." Licentiate thesis, Luleå : Luleå University of Technology, 2007. http://epubl.ltu.se/1402-1757/2007/16/.

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Ahmed, Kafil Uddin. "Novel metamaterial frequency discriminating devices for next generation wireless communication systems." Thesis, London Metropolitan University, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.590127.

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In this research, novel meta material structures based on microstrip integrated circuit technology have been investigated for filter application in the next generation of microwave wireless communication systems. A number of novel microstrip planar filter structures have been developed that are able to meet the stringent requirements for high-performance systems and subsystems, such as sharp-cutoff frequency response, low passband insertion-loss and high return-Joss, high out-af-band rejection, compact size, low cost and ease of integration. The filters are approximately 70% smaller than their conventional counterparts. Analysis and mathematical modeling of these microstrip devices involved the use of transmission-line theory and EM simulation tools which were based on the method of moments and finite element analyses. Measured results were used to validate the predicted behavior and performance of these devices. In fact there was good agreement with the theory and simulation modeling. A Composite right/left-handed (CRLH) metamaterial unit-cell whose ground-plane is defected with a rectangular dielectric slot was used to develop a single and multi-pole bandpass filters. The unit-cell comprises of serial inter-digital capacitors whose junction is connected to a short-circuited inductive stub. By defecting the ground-plane of the unit-cell 's structure with a dielectric slot, which is located immediately below the unit-cell, enables substantial tuning of the filter's centre frequency in the order of 26.5%. This was achieved with minimal effect on the unitcell's insertion- and return-loss performance as well as its selectivity. The filters were fabricated on conventional dielectric substrate and their performance measured to verify the design methodology. The proposed technique eases the trade-off constraints that plague conventional filter designs and makes possible the realization of challenging filter specifications constituted from CRLH unit-cells using distributed transmission-lines. A novel multilayer technique is presented that enables (i) the control of the filter's bandwidth, (ii) significantly improves its passband selectivity, and (iii) enhances its out-of-band rejection without affecting the filter's overall dimensions. The technique involves implementation of identical filter structures on both sides of the dielectric substrate that are interconnected through vias. The filter circuit is laid on top of another identical substrate with a ground-plane. This structure results in a device that exhibits a sharp selectivity that is substantially smaller than traditional filter constructions. The sharpness of the filter is due to the upper and lower transmission zeros present on either side of the filter's passband being shifted closer together which causes reduction in its bandwidth. This effect is opposite to that encountered in conventional multilayer filter structures. It is shown the filter's bandwidth can be controlled while maintaining a good passband insertion- and return-loss performance, i.e. <1.2 dB and >10 dB, respectively. Furthermore, the proposed filter is relatively easy to fabricate using conventional technology. A diplexer was developed based on the proposed multilayer technique and was shown to yield a high out-af-band rejection and high isolation between the two very closely spaced channels. Normally isolators are used to provide isolation between channels in order to prevent inter-channel interference. The technique is relatively simple to realize and cost effective to manufacture. Design methodology and experimental results are presented that show good correlation between the measured and simulation results. This diplexer should find application in multi band wireless communication systems. A triplexer deSign is also presented whose multiband performance was created using CRLH unit-cell structures. The three passband channels of the triplexer have a common input splitter and transmission-line matching network is used to ensure high isolation between the channels is maintained in order to prevent undesired interaction between the channels which would otherwise adversely affect the triplexer's passband response. This was achieved using stepped impedance lines (SIL). No isolators were necessary using the proposed technique. It is also shown that by curving the SIL can provide enhancement in the triplexer's loss performance, bandwidth, and suppression of high order spurii. The design analysis and performance of the triplexer was verified via fabrication and measurement. A novel compact microstrip wideband bandpass filter was presented for wideband application that possesses good insertion- and return-loss, sharp frequency selectivity and high out-of-band rejection. The proposed filter comprises of two inter-digital capacitors with four inductive stubs. It employs a T-shaped open stub that is inserted between the symmetrical unitcell structures.

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Goergen, Frank. "Software Development for Wireless Communication between Mobile Robots and Handheld Devices." Honors in the Major Thesis, University of Central Florida, 2003. http://digital.library.ucf.edu/cdm/ref/collection/ETH/id/695.

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This item is only available in print in the UCF Libraries. If this is your Honors Thesis, you can help us make it available online for use by researchers around the world by following the instructions on the distribution consent form at http://library.ucf
Bachelors
Engineering and Computer Science
Computer Engineering

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Macaluso, Roberto. "GainNaAs 1.3 #mu#m microactivty structures for advanced data-communication devices." Thesis, University of Strathclyde, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.288591.

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Martins, Henrique Manuel Gil. "Use of mobile Information Communication Technology (ICT) devices in clinical settings." Thesis, University of Cambridge, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.614177.

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Rajarajan, Muttukrishnan. "Computer modelling of compact photonics devices for optical communications." Thesis, University of London, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301050.

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Cryan, M. J. "Novel gallium arsenide monolithic microwave devices and their applications." Thesis, University of Bath, 1994. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.260281.

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Hall, John Robert. "Linguistic markers of association as persuasive devices in mediated appeals." Diss., The University of Arizona, 1992. http://hdl.handle.net/10150/186033.

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The framework developed and tested in this study argues that the success of mediated persuasive appeals can be partially explained by the interaction among linguistic and extra-linguistic variables. It was predicted that sources would be most persuasive when the topic was of little importance and the source was liked by the viewer and that sources using intense language would be evaluated as believing the arguments presented more than sources using less intense language. These predictions were supported. The study also supported a predicted interaction between familiarity and liking such that familiarity works to the advantage of liked sources and to the disadvantage of disliked sources. It was also posited that intensity would have a differentially effective role for liked and disliked sources such that it works to the advantage of liked sources and to the disadvantage of disliked sources. This hypothesis was solely supported in proattitudinal appeals when intensity was operationalized using structural criteria and in counterattitudinal appeals when intensity was operationalized as perceived by the viewer. Finally, a 3-way interaction was predicted suggesting that familiarity and intensity would combine such that high familiarity results in increases in attitude change with the use of language that is more intense than expected for liked sources and decreases in attitude change for disliked sources. This hypothesis was not supported. In fact, both highly familiar sources benefited from use of language that was less intense than expected.

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Macke, Robin A. (Robin Ann). "Preservice Teacher Attitudes towards Nonvocal Individuals using High Technology Augmentative Communication Devices versus Low Technology Communication Boards." Thesis, University of North Texas, 1992. https://digital.library.unt.edu/ark:/67531/metadc277750/.

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The attitudes of preservice teachers towards individuals who are nonvocal and using either a high technology augmentative communication (HAC) device or a low technology communication board were investigated. A rating scale was devised, consisting of three sub-scales. The three sub-scales measured preservice teachers' estimates of intelligence, academic potential, and social acceptance in the regular education setting. Reliability and validity were established through a pilot study. Preservice teachers viewed videotapes of children using either high technology or low technology augmentative communication devices and subsequently completed the rating scale based on the videotapes. Results indicated that preservice teachers perceived the same child as having greater academic and social acceptance potential when using high technology augmentative communication.

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Cheung, King-yin Henry. "Applications of photonic parametric processors in optical communication systems." Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/HKUTO/record/B39558514.

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Cheung, King-yin Henry, and 張景然. "Applications of photonic parametric processors in optical communication systems." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B39558514.

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Danielson, Priscilla Mary. "Perceptions of Working Memory Use in Communication by Users of Speech-Generating Devices." Diss., Temple University Libraries, 2016. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/380748.

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Educational Psychology
Ph.D.
Augmentative and alternative communication (AAC) is defined as “all forms of communication (other than oral speech)…used to express thoughts, needs, wants and ideas” (“Augmentative and Alternative Communication (AAC),” 2012). Working memory is a temporary cognitive process, which briefly maintains and manipulates information while it is being encoded as a part of long-term memory (Engle, Nations, & Cantor, 1990; “Introduction to Working Memory”, 2007). It has been suggested that based upon the unique skill set and needs of users of AAC systems, the design of these systems should reflect knowledge gleaned from the cognitive sciences (Light & Lindsay, 1991) with training and implementation of AAC incorporating an understanding of the cognitive processes impacting memory, learning, and visual processing (Light & Lindsay, 1991; Wilkinson & Jagaroo, 2004). This study sought to examine how users of AAC managed and perceived the cognitive load associated with working memory demands while communicating and what specific strategies and/or design features users of AAC perceived they used during conversation when using AAC. Results revealed an overall large amount of variability in participants’ responses. Length of symbol/word sequences, word prediction, seeing the message as it is being created, attention to the conversational topic, and attempting to remember what their conversational partner said appeared to be judged as having the highest degree of importance for the use of a speech generating device and success and message completion in conversation. Errors in conversational while using a speech generating device and stressors during the conversational process appeared to be most closely related to reported lack of time to create messages and the time it takes to create messages. Users of AAC did not report high frequency of actives attention to the working memory processes and design features.
Temple University--Theses

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Bridle, Robert Angus. "Adaptive user interfaces for mobile computing devices /." View thesis entry in Australian Digital Theses Program, 2008. http://thesis.anu.edu.au/public/adt-ANU20081117.184430/index.html.

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Kroll, Carly. "Communicating Augmented Reality Devices Improving Technology Acceptance among Electric Utility Field Workers." Thesis, Marquette University, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10791776.

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Augmented Reality (AR) is very useful for many different fields and purposes such as entertainment, education, military, navigation, industrial, or electric utility. Electric utilities find use in AR due to the flexibility of location and the real-time information sharing with visuals to keep employees safe and efficient. This exploratory study investigated the use of infographic templates as a way to introduce this new technology to line workers in the electric utility field. Infographics were used as a way to prime workers to be more aware of the technology and its possible uses as well as usefulness. Through the use of Communication Accommodation Theory and the Technology Acceptance Model, the researcher found evidence indicating that presenting information in a clear and interesting way increased electric utility workers desire to adopt the new technology through perceived ease of use and perceived usefulness (Davis, Bagozzi & Warshaw, 1989).

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Rahmani-Shirazi, Ashiyan Ian. "Gender Praxis| Rural Fiji Radio and Mobile Devices." Thesis, University of Hawai'i at Manoa, 2019. http://pqdtopen.proquest.com/#viewpdf?dispub=13422469.

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This communications study looks at gender-based self-reflexive theoretically guided practice, “praxis,” to explore the way in which a women's community media organization, femLINKpacific, pursues its goals of enhancing women's participation in governance structures and resiliency to extreme weather conditions. This study contributes to the nascent literature on mobile device and radio interaction by exploring the way in which women in rural Fiji utilize mobile devices to interact with femTALK, the community radio station of femLINKpacific. The study is based on the theoretical frameworks of inclusive innovation, post-development theory, and participatory communications theory in the context of gender-based ICT4D. Two main platforms, Mobile Suitcase Radio (MSR), a portable radio platform, and Women’s Weather Watch (WWW), a mobile-phone based weather reporting network, and an additional non-mediated communication venue of monthly women’s gatherings were explored through a 3-phase study, utilizing interviews and focus groups, with radio station staff and women leader’s networks.

Main findings included the role of WWW to transmit information for preparedness for Tropical Cyclone Winston, and indigenous food practices shared through the various platforms, as well as the role of MSR, when used in conjunction with the issues shared at the monthly consultations, to bring greater awareness to the women’s “voice.” This study extends to understanding the role of mutually supportive, systematic processes to enhance women's participation in governance structures, including the role and effectiveness of inter-ethnic groups in addressing community issues, and capacity building through incremental acclimatizing activities.

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Alkureishi, Esam. "Implementation and Evaluation of Communication Tables and Link Scheduling for WirelessHART Devices." Thesis, Tekniska Högskolan, Högskolan i Jönköping, JTH, Data- och elektroteknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-14611.

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Tulli, Domenico. "Micro-nano structured electro-optic devices in LiNbO3 for communication and sensing." Doctoral thesis, Universitat Politècnica de Catalunya, 2012. http://hdl.handle.net/10803/81118.

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A material that is enabling integrated optics is the ferroelectric crystal Lithium Niobate (LiNbO3), which has excellent electro-optical, acousto-optical and nonlinear optical properties. Moreover, it can be doped with laser-active ions and allows for simple fabrication of low-loss optical waveguides. The broad aim of this work is to develop and introduce advanced micro- and nano-fabrication techniques for LiNbO3 and a new class of integrated based telecommunication and sensing devices. The techniques developed include precise micro-domain inversion, etching, bonding and thin film fabrication. From a device point of view, domain inversion is used to improve the electro-optic response of LiNbO3 waveguide modulators in terms of bandwidth and driving voltage. With respect to standard single-domain structures, larger bandwidths and lower driving voltages can be obtained, thus achieving figure of merits for the electro-optic response that are up to 50% larger. As a demonstration, a chirp-free modulator, having ~2V switching voltage and bandwidth of 15 GHz, was fabricated by placing the waveguide arms of a Mach-Zehnder interferometer in opposite do- main oriented regions. The modulator could be driven in a single-drive configuration with inexpensive low-voltage drivers, e.g. a SiGe based RF amplifier, typically used for electro-absorption devices. A further aspect of this work focuses on the development of devices for the precise measurement of strong electric fields, which are typically generated in power stations and transmission lines. Therefore, two new integrated electric field sensors are proposed, each of which exploits the aforementioned micro-fabrication techniques. The first device is based on a proton-exchange waveguide at cut-off, centered on a few microns wide domain-inverted region in a z-cut LiNbO3 substrate. The sensor’s performance is demonstrated by detecting DC fields up to 2.6 MV/m and high-frequency (1.1 GHz) fields ranging from 19 V/m to 23 kV/m. The second proposed device is fabricated by direct bonding a z-cut LiNbO3 substrate on top of a cut-off proton-exchanged waveguide centered on the domain-inverted region. It is possible to detect electric fields as high as 2 MV/m at low frequency with improved sensitivity compared to the previous device. These features make the devices suitable for use in high electric field and harsh conditions without endangering the operator. The conclusions section of the Thesis presents possible future developments which will contribute to increase the impact of the work in the optical telecommunication and sensing industries. After a brief introduction, the second chapter describes the basic properties of the material used in the thesis work: Lithium Niobate (LiNbO3). This includes the properties related to its ferroelectric crystal structure and the subsequent applications. Chapter three presents the micro-fabrication techniques, over 3 inch LiNbO3 wafers, developed at ICFO during this work. The chapter begins with a description of waveguides fabrication by Annealed Proton Exchange (APE). The mid-part of the chapter outlines the fabrication procedure for domain inversion using electric field poling technique and liquid electrodes while the last part describes the bonding technique to permanently join LiNbO3 with different substrates, namely Si, SiO2 and another LiNbO3. Moreover, lapping and polishing techniques for thin plate fabrication are presented. The forth chapter firstly introduces the fundamentals and main characteristics of travelling-wave LiNbO3 Mach-Zehnder modulators. Secondly, a new modulator design is proposed. It is based on domain inverted LiNbO3, with improved performance with respect to existing devices. The modulator characterization and the results obtained from the new design are presented. The chapter five begins with a literature review about DC and low frequency electric field optical sensors. Afterwards, two novel all-optical electric field sensors are presented. Both devices are based on a proton-exchange, domain inversion and bonding techniques. The sensors characterization, including the test set-up and the performance results are discussed. Finally, in chapter six, several conclusions on the thesis work and possible future work directions are presented.
Uno de los materiales que permite el avance de la tecnología de dispositivos ópticos integrados es el niobato de litio (LiNbO3). Se trata de un cristal ferro-eléctrico, con excelentes propiedades electro-ópticas, acusto-ópticas y no lineales. Además, es posible fabricar guías de onda de bajas pérdidas mediante las técnicas de intercambio protónico (PE) y difusión de titanio. El objetivo principal de este trabajo es el desarrollo y la introducción tanto de las técnicas avanzadas de micro-nano fabricación para el niobato de litio como de nuevos dispositivos ópticos integrados para las comunicaciones ópticas y la detección de campo eléctricos de alto voltaje. La técnicas de fabricación desarrolladas incluyen inversión de dominios mediante la técnica de poling de alto voltaje, grabado, bonding y capas delgadas. Desde el punto de vista de los dispositivos, la inversión de dominios ha sido utilizada para mejorar la respuesta electro-óptica de los moduladores en LiNbO3 en términos de ancho de banda (BW) y voltaje de control (Vπ). En comparación con los moduladores comerciales actuales de un único dominio, con esta técnica es posible obtener mayores anchos de banda y menores voltajes de control resultando en un aumento del 50% del producto BW·Vπ. Para demonstrar la eficacia de la técnica desarrollada, se ha fabricado un modulador Mach-Zehnder chirp-free poniendo los brazos del interferómetro en dos regiones de dominios opuestos. De las mediciones efectuadas se han obtenidos valores de voltaje de control de 2V y ancho de banda de 15 GHz. Estos resultados muestran que los dispositivos desarrollados pueden reducir el coste total de funcionamiento, ya que permiten el uso de controladores económicos de Si-Ge que operan en el rango de los 2V. Otro aspecto de este trabajo se enfoca en el desarrollo de dispositivos para medir, de forma exacta, altos campos eléctricos, que normalmente son generados en las centrales eléctricas y en las líneas de transmisión. Por este motivo, se han desarrollado dos sensores de campo eléctrico mediante las técnicas de micro-fabricación anteriormente mencionadas. El primer dispositivo está basado en una guía fabricada mediante intercambio protónico en LiNbO3 z-cut, diseñada a la frecuencia de corte y centrada en una región de dominio invertido de 10 micras de ancho y 10mm de largo. El rendimiento del dispositivo se ha demostrado detectando campos a baja frecuencia con amplitudes de hasta 2.6MV/m y campos a la frecuencia de 1.1GHz con amplitudes desde 19V/m hasta 23kV/m. El segundo dispositivo se ha fabricado mediante bonding directo de un sustrato de LiNbO3 encima de una guía PE diseñada a la frecuencia de corte y centrada en una región de dominio invertido de 10 micras de ancho y 10mm de largo. El dispositivo se ha caracterizado a baja frecuencia y ha sido posible medir campos eléctricos de hasta 2MV/m con un aumento de sensibilidad comparado con el primer dispositivo fabricado sin la técnica del bonding. Estos resultados muestran que los dispositivos desarrollados pueden ser utilizados para mediciones de campos eléctricos intensos en condiciones peligrosas sin ningún riesgo para el operador. Después de una breve introducción en el Capítulo 1 de esta Tesis, las propiedades del LiNbO3 se discuten en el Capítulo 2, prestando especial atención a sus características ópticas y electro-ópticas. El Capítulo 3 presenta las técnicas de micro fabricación desarrolladas durante este trabajo sobre sustratos de 3 pulgadas. En particular, se presentan las técnicas de fabricación de guías mediante intercambio protónico, de inversión de dominios mediante poling de alto voltaje, de bonding de LiNbO3 con diferentes sustratos (LiNbO3 , SiO2, Si) y la fabricación de capas delgadas. El Capítulo 4 ofrece una introducción sobre los moduladores interferométricos Mach-Zehnder de onda propagada, presentando sus principales características. Además se presenta una nueva estructura de modulador basada sobre inversión de dominios y los resultados obtenidos. El Capítulo 5 empieza con una introducción sobre los sensores de campo eléctrico y después se presentan dos nuevos sensores de campo eléctrico completamente ópticos fabricados en LiNbO3 z-cut. Los dispositivos están basados en las técnicas de intercambio protónico, inversión de dominios y bonding directo. Finalmente, en el Capítulo 6 se presentan las conclusiones y posibles desarrollos futuros que pueden contribuir al aumento del impacto de este trabajo en las industrias de comunicaciones ópticas y de detección.

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48

Odelius, Johan. "Communication acoustics in classroom environments : on the use of assistive listening devices /." Luleå : Division of sound and vibration, Department of human work sciences, Luleå university of technology, 2010. http://pure.ltu.se/ws/fbspretrieve/4485381.

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Stålnacke, Daniel. "Designing and Implementing Communication and a Graphical Interface for Antenna Test Devices." Thesis, Umeå University, Department of Computing Science, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-33772.

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Esrange Space Center, located in Kiruna, is a company which specializes in the area of satellite service as well as rocket and balloon launches. To communicate with the satellites Esrange use antennas that is between eight and thirteen meters in diameter. The antennas must always be ready to operate which is why there is a need for an application to test the antennas when they are not used.This master's thesis work aims to develop such a system that tests the antennas when they are not communicating with satellites. This report contains background information about the problem and system requirements as well as the solution and description of the developed system. It also contains an in-depth study about similar applications that has been developed by others.To solve the problem, a client-server application was developed. The server controls the test devises used to test the antennas and the client gives the users a GUI to control the server and its functions. An automated system called OASIS, developed at Esrange, was included in the solution to make it possible to automate some of the core tests.

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van, Leeuwen Daniel, and Leonel Taku Ayuk. "Security testing of the Zigbee communication protocol in consumer grade IoT devices." Thesis, Högskolan i Halmstad, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-40189.

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With the ever increasing number of Internet of Things devices going out on the market for consumers that are Zigbee certified there is a need for security testing. This is to make sure that security standards are upheld and improved upon in order to make sure networks are protected from unauthorized users. Even though a lot of research and testing has been done on the Zigbee key exchange mechanism, called Zigbee commissioning, improvements have still not been enough with severe vulnerabilities in consumer grade devices still existing today. The devices tested in this study use EZ-mode commissioning in order to exchange the network key between a Zigbee coordinator and a Zigbee end device in order to encrypt later communication after being paired. By using a simple radio receiver and a packet capturing program such as Wireshark an eavesdropping attack was conducted in order to capture the network key. The experiment demonstrates that this is still a weak point as the network key was successfully captured using eavesdropping. The analysis of the results show that previous criticisms of Zigbee commissioning have still not fully been addressed and can be a potential weak point in networks that use Zigbee certified IoT products.

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Dissertations / Theses on the topic 'Communication devices for peop'

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