International Telemetering Conference Proceedings / October 26-29, 1992 / Town and Country Hotel and Convention Center, San Diego, California / In this paper, we investigate high-capacity fiber-optic networks for real-time telemetry applications. The network topologies and related network components are analyzed for telemetry fiber-optic Local Area Network (LAN) and Metropolitan Area Network (MAN) as well as MAN internetworking with LANs. Two types of multiplexing techniques, namely, Wavelength Division Multiplexing and Time Division Multiplexing, are proposed to support real-time high-capacity telemetry applications, and the perspective of such networks is also considered. Finally, the optical modulation technique and the choice of optical devices are discussed, which are based on improving the reliability of fiber-optic LANs and MANs.

京都大学 / 0048 / 新制・課程博士 / 博士(人間・環境学) / 甲第22549号 / 人博第952号 / 新制||人||226(附属図書館) / 2019||人博||952(吉田南総合図書館) / 京都大学大学院人間・環境学研究科相関環境学専攻 / (主査)教授 内本 喜晴, 教授 吉田 寿雄, 准教授 戸﨑 充男 / 学位規則第4条第1項該当 / Doctor of Human and Environmental Studies / Kyoto University / DFAM

<p>Paper-based flexible devices represent a new frontier in electronics technology. The research has focused on the fabrication of the lightweight, and flexible paper-based lithium ion batteries. A lithium ion battery relies on the interplay of multiple components. These components themselves, as well as the processes used to create them, need to be adjusted and modified in order to achieve a fully flexible lithium ion battery. These components include the electrode current collector, active material, and electrolyte. By modifying these components to be fully flexible and resistant to damages caused by deformation, a fully flexible battery can be achieved.</p> <p> </p> <p>Herein, the paper-based platform utilized is key to provide flexibility for the battery components. The goal of this work not only focused on the creation of a paper-based flexible battery to be used as an integrable energy storage system for flexible devices, but also on developing methodologies and processes that can advance the emerging area of paper-based electronics, where different functional units must be fabricated within a single paper substrate. The key to make effective paper-based batteries, is to achieve a highly conductive paper structure as the base. In this work, conductive nanomaterials including carbon nanotubes (CNT) and graphene were used to fabricate conductive paper, where wood microfibers were coated with layers of these nanomaterials via layer-by-layer nanoassembly. These fibers were then combined into paper sheets. The resulting paper offers a conductive and porous base for electronic devices that utilized only small quantities of CNT or reduced graphene oxide (rGO) to provide length resistances of 468 Ω/cm and 74.6 Ω/cm, respectively for each fabricated conductive paper. </p> <p> </p> <p>Flexible lithium ion batteries were then made by using CNT paper-based electrodes and a solid polymer gel electrolyte. The electrodes were made by deposition of lithium active materials over the conductive paper and where shown to be flexible, durable, and light weight. With respect to the electrolyte, a new type of gel electrolyte based on PVDF-HFP was fabricated to overcome problems related to the use of liquid electrolytes in flexible batteries. This gel, which provides a high electrolyte uptake (450% by weight), was made by infusing both liquid and ceramic electrolytes inside a polymer gel structure and demonstrated conductivity up to 10^-4 S/cm. The paper-based battery developed with these new materials has a comparable capacity to commercial batteries and represents a flexible and light weight alternative. The use of ultra-high capacity lithium compounds as cathode materials, such as vanadium pentoxide (with theoretical capacities of 440 mAh/g) in conjunction with rGO-paper as a stand-alone electrode (with a reversible capacity 546 mAh/g) were also explored and results will be discussed. </p> <p> </p> <p>This research has led to the development of a novel method of making a fully flexible lithium ion batteries, using paper-based current collectors, leak proof polymer gel electrolytes and ultra-high capacity lithium ion active materials. Thus, flexible high conductive paper-based current collectors, polymer-gel electrolytes, vanadium based ultra-high capacity cathode electrodes, and graphene-based stand-alone paper-based anodes have been developed and tested.</p> <p> </p>

The aim of this thesis is to evaluate the usefulness of Ostrava airport in its current state for large aircraft. An introductory part includes a list of the aircraft of particular category and characterizes the current parameters of the Ostrava airport. The following part shows the requirements of the selected group of airplanes on the airport facilities and dimensions of the runway system. Furthermore, it proposes a solution of the unsatisfactory parameters of the airport.

Data centre networks are currently experiencing a dramatic increase in the amount of network traffic that needs to be handled due to cloud technology and several emerging applications. To address this challenge, mega data centres are required with hundreds of thousands of servers interconnected with high bandwidth interconnects. Current data centre networks, based on electronic packet switches, consume a huge amount of power to support the increased bandwidth required by the emerging applications. Optical interconnects have gained more and more attentions as a promising solution offering high capacity and consuming much lower energy compared to the commodity switch based solutions. This thesis provides a thorough literature study on optical interconnects for data centre networks that are expected to efficiently handle the future traffic. Two major types of optical interconnects have been reviewed. One is referred to hybrid switching, where optical switching deals big flows while electronic switches handles traffic in packet level. The other one is based on all-optical switch, where power-consuming electronic interconnects can be completely avoided. Furthermore, the thesis includes a qualitative comparison of the presented schemes based on their main features such as topology, technology, network performance, scalability, energy consumption, etc.

Society of today is struggling with both large amounts of emissions as well as congestion on the roads. For this reason, AFRY in collaboration with Volvo GTT is working on develop and implement longer and heavier transports in traffic network. These combinations are called high capacity transport and have high performance-based demands. Dynamic stability is one demand that can be improved for the DUOCAT, which is a high capacity transport combination. The hypothesis is that a displacement backward in the direction of travel of the v-stay can improve the dynamic stability. The v-stay is a component of the rear wheel suspension and has an important function regarding dynamic stability by absorbing lateral forces. To achieve better dynamic stability, the goal is to create counter steering on the rear axle of the DUO-CAT through small design changes on the v-stay. The suggestion from Volvo is to move the v-stay backward in the direction of travel, which in this thesis has become the focus in both concept generation and design work. The thesis includes development of new concepts of the v-stay. An extensive evaluation process consisting of dynamic analysis was carried out in PTC Creo Parametric, which made it possible to compare the new concepts with the current v-stay. An important part of the thesis is to obtain a simplified model that simulate the physical conditions. The delimitations are to examine lateral acceleration with load on the axle and friction between asphalt and wheels. The maneuver in the analyses emulates a quick lane change at 80 km/h. This has resulted in a new concept that includes the current v-stay where only the position on the frame and axle is changed with the help of new fastening components. The new concept provides an increased counter steering of 6%. The conclusion is that a displacement backwards in the direction of travel of the vehicle gives an increased counter steering. Future work is required to achieve the desired improved steering and safety requirements.

Volvo trucks are involved in a project with vehicle combinations longer than 25.25 meters and/or with a weight of more than 64 tons. Those combinations are called high capacity transport (HCT). Some of the vehicle combinations are now driven with exemptions for the coupling equipment. The exemption is needed because according to a standard the theoretical transmitted forces between the dolly and the truck exceed the value that the coupling components have been certified for. The theoretical transmitted forces are called performance indexes. This limits the development but the exception could be avoided by using a hinged drawbar on the dolly.  This thesis aims to investigate what needs to be done in order to introduce dolly with hinged drawbar in longer and heavier vehicle combinations. A literature study and interviews were conducted to find problems that could be expected when using hinged drawbar on dolly and to investigate how the performance indexes for a specific vehicle combination should be calculated. Thereafter a dolly was put together through a product development process. Then concepts to solve a problem that was noticed through the literature study were developed. The concepts were sketched, evaluated in a matrix and thereafter the winning concept was modelled in detail in computer aided design (CAD).   According to the traffic definition in Sweden a dolly with hinged drawbar is violating the law. It defines a dolly as a module with rigid drawbar. On the other hand, the European Union defining a dolly as a trailer with fifth- wheel made to convert a semi-trailer into a full trailer. They don’t mention anything that contradicts to the usage of hinged drawbar. So the Swedish definition of a dolly needs to be challenged.   Simulations have shown that the braking performance will be worse when using a dolly with hinged drawbar compared to using a dolly with rigid drawbar. Therefore concepts to improve the braking performance of the dolly have been developed. The concept was to look the fifthwheel from pivoting around a horizontal axle perpendicular to the driving direction. By doing so the dolly and semi-trailer will become more like a full trailer and that would better the braking performance.  Through interviews and literature study it was noticed that the high performance indexes were calculated in an incorrect way. The highest forces are generated through interaction forces which are only affected by the vehicles closest to the coupling components. Therefore a calculation model need to be modified for this. Three calculation models were tested on the vehicle-combination. Two of these generated performance indexes that were reasonable. The calculation models were ISO-combination 3 and a model developed by Sweatman (1980). These two calculation models are modified for vehicle combinations that includes three vehicles. / Volvo lastvagnar ingår i ett forskningsprojekt med lastbilskombinationer som är längre än 25,25  meter och/eller väger mer än 64 ton. Ett sådant fordon kallas högkapacitetstransport (HCT). Idag körs vissa av dessa fordon med dispenser för kopplingsutrustningen. Detta då de teoretiska överförda krafterna mellan lastbil och dolly enligt en standard får värden som är högre än vad kopplingsutrustningen är certifierad med. De teoretiska överförda krafterna benämns som prestandaindex. Denna dispens skulle kunna undvikas genom att använda en ledad dragstång på dollyn.  Detta examensarbete syftar till att undersöka vad som behöver göras för att introducera dolly med ledad dragstång i längre och tyngre fordonskombinationer. En litteraturundersökning samt intervjuer genomfördes för att upptäcka problem som kan uppstå vid användande av dolly med ledad dragstång. Även en undersökning gällande hur prestandaindex ska beräknas på rätt sätt genomfördes.  Därefter konstruerades en dolly genom en produktutvecklingsprocess. Koncept för att lösa ett problem som noterades under litteraturundersökningen utvecklades. Koncepten skissades och blev sedan utvärderade genom en matris. Det vinnande konceptet konstruerades i CAD.   Från litteraturstudien visade det sig att det finns en motstridighet i den svenska definitionen gällande användandet av ledad dragstång på dolly. I Sverige definieras dolly som en kärra. En kärra definieras som en modul med stel dragstång. Däremot definierar EU dolly som en trailer som konverterar en semi-trailer till en full trailer. Där nämns ingenting som kan stoppa användandet av dolly med ledad dragstång. Därför borde den svenska definitionen utmanas.   En dolly med ledad dragstång förväntas ha sämre bromsprestanda än en vanlig dolly. Koncept utvecklades för att förbättra bromsprestandan på dollyn. Konceptet som vann var att låsa vändskivan från att vridas runt en horisontell axel vinkelrätt till åkriktningen. På så viss blir kombinationen dolly, semi-trailer mer som en full trailer vilket skulle innebära en bättre bromsprestanda.  Från intervjuer med kunniga personer och från litteraturstudien framkom det att de höga prestanda indexen var felaktigt beräknade. Det blev även känt att de största krafterna genereras genom interaktionskrafter som endast påverkas av de närmaste fordonens vikt. Tre olika beräkningsmodeller testades där två utav dem gav värden som kan anses vara rimliga. Beräkningsmodellerna var ISO-kombination 3 och en modell utvecklad av Sweatman (1980). Dessa två är anpassad för kombinationer som innehåller 3 fordon.

Cette thèse aborde les problèmes liés à la protection de maillages d'objets 3D. Ces objets peuvent, par exemple, être créés à l'aide d'outil de CAD développés par la société STRATEGIES. Dans un cadre industriel, les créateurs de maillages 3D ont besoin de disposer d'outils leur permettant de vérifier l'intégrité des maillages, ou de vérifier des autorisations pour l'impression 3D par exemple. Dans ce contexte nous étudions l'insertion de données cachées dans des maillages 3D. Cette approche permet d'insérer de façon imperceptible et sécurisée de l'information dans un maillage. Il peut s'agir d'un identifiant, de méta-informations ou d'un contenu tiers, par exemple, pour transmettre de façon secrète une texture. L'insertion de données cachées permet de répondre à ces problèmes en jouant sur le compromis entre la capacité, l'imperceptibilité et la robustesse. Généralement, les méthodes d'insertion de données cachées se composent de deux phases, la synchronisation et l'insertion. La synchronisation consiste à trouver et ordonner les éléments disponibles pour l'insertion. L'un des principaux challenges est de proposer une méthode de synchronisation 3D efficace qui définit un ordre sur les composants des maillages. Dans nos travaux, nous proposons d'utiliser les sommets du maillage, plus précisément leur représentation géométrique dans l'espace comme composants de base pour la synchronisation et l'insertion. Nous présentons donc trois nouvelles méthodes de synchronisation de la géométrie des maillages basées sur la construction d'un chemin hamiltonien dans un nuage de sommets. Deux de ces méthodes permettent de manière conjointe de synchroniser les sommets et de cacher un message. Cela est possible grâce à deux nouvelles méthodes d'insertion haute capacité (de $3$ à $24$ bits par sommet) qui s'appuient sur la quantification des coordonnées. Dans ces travaux nous mettons également en évidence les contraintes propres à ce type de synchronisation. Nous discutons des différentes approches proposées dans plusieurs études expérimentales. Nos travaux sont évalués sur différents critères dont la capacité et l'imperceptibilité de la méthode d'insertion. Nous portons également notre attention aux aspects sécurité des méthodes. / This thesis addresses issues relating to the protection of 3D object meshes. For instance, these objects can be created using CAD tool developed by the company STRATEGIES. In an industrial context, 3D meshes creators need to have tools in order to verify meshes integrity, or check permission for 3D printing for example.In this context we study data hiding on 3D meshes. This approach allows us to insert information in a secure and imperceptible way in a mesh. This may be an identifier, a meta-information or a third-party content, for instance, in order to transmit secretly a texture. Data hiding can address these problems by adjusting the trade-off between capacity, imperceptibility and robustness. Generally, data hiding methods consist of two stages, the synchronization and the embedding. The synchronization stage consists of finding and ordering available components for insertion. One of the main challenges is to propose an effective synchronization method that defines an order on mesh components. In our work, we propose to use mesh vertices, specifically their geometric representation in space, as basic components for synchronization and embedding. We present three new synchronisation methods based on the construction of a Hamiltonian path in a vertex cloud. Two of these methods jointly perform the synchronization stage and the embedding stage. This is possible thanks to two new high-capacity embedding methods (from 3 to 24 bits per vertex) that rely on coordinates quantization. In this work we also highlight the constraints of this kind of synchronization. We analyze the different approaches proposed with several experimental studies. Our work is assessed on various criteria including the capacity and imperceptibility of the embedding method. We also pay attention to security aspects of the proposed methods.

Bakgrund: Planeringsstadier inom skogsindustrin sker på både lång, medel och kort sikt. Virkesflödesplanering startar med en långsiktig strategisk planering rationaliseras på taktisk och operationell nivå desto närmare i tiden avverkning kommer. Planering i flera stadier utförs för att närma sig ett högt resursutnyttjande där verksamheten arbetat med att planera och utveckla sina aktiviteter. En stor aktivitet inom virkesflödet är transport. Skogsindustrin kör tunga transporter vilket ställer krav på planeringen av faktorer som vikt, volym och distans. Tunga transporter utreds för tillfället där målet är att kunna öka tillåten bruttovikt på svenska vägar. För skogsindustrin ses denna utveckling som en viktig del i ökad konkurrenskraft. Syfte: Studien syfte är att identifiera ett optimalt scenario av kostnadsbesparingar för Skogsbolaget AB genom ett förbättrat arbete med virkesflödesplanering samt undersöka framtida användande av HCT fordons påverkan på kostnader inom virkesflödet. Metod: Denna fallstudie har en kvalitativ inriktning som forskningsdesign och tillvägagångssätt för studien. Även om vissa matematiska beräkningar används anses den vara av kvalitativ natur. I studien har en mönsterjämförelse mellan teori och insamlad empiri utförts. Data har samlats in genom ostrukturerade intervjuer samt genom simuleringsverktyget Woodflow. Respondenter bestod till början av produktionschefen tillika författarnas kontaktperson på Skogsbolaget AB för att sedan genom snöbollsurval expanderat till logistikchef och logistiker på Skogsbolaget AB. Slutsats: Studien har identifierat icke optimala delar av Skogsbolaget ABs virkesflöde och var kostnader uppstår. Ett förbättrat planeringsarbete med fokus på kostnadsbesparingar har tagits fram för att förbättra de delar som krävs. Planeringsarbetet sker på strategisk-, taktisk-, och operationell nivå. Total kostnadsbesparing för hela flödet har simuleras fram för att sedan brytas ned till produktgruppsnivå. De största kostnadsbesparingarna är funna i sågtimmerflödet, där mer specifikt sågtimmer tall har störst kostnadsbesparing. Därför rekommenderas det att sågtimmer tall flödet ska vara en start i planeringsarbetet. Vidare har tre olika scenarion skapats där 50-, 75- och 100 % HCT fordon används vid transportarbetet. Genom att använda HCT fordon sjunker fasta kostnader då de sprids ut på en högre transporterad volym per lastbil och rörliga kostnader sjunker enl. presenterad prislista per km. Det resulterar i att 100 % HCT fordon innebär högst kostnadsbesparingar, men det är i grunden Trafikverkets ansvar att tillhandahålla möjligheten att använda HCT fordon i den utsträckningen.

Este trabalho teve como objetivo utilizar um tensiômetro de alta capacidade (TAC) para realizar medidas diretas de sucção em ensaios de resistência ao cisalhamento de um solo compactado. Foram realizados ensaios de resistência à compressão triaxial do tipo consolidado drenado na condição saturada, ensaios consolidados não drenados na condição não saturada e ensaios de resistência à compressão simples. Os ensaios de compressão simples foram realizados em uma série de repetibilidade e outras duas para a verificação da influência da sucção na resistência de um solo compactado, fazendo-se variar a massa específica aparente seca do solo e o teor de umidade. Em todos os ensaios de compressão simples o TAC registrou aumento da sucção até cerca de 3% de deformação axial, quando a partir daí a sucção tendeu a estabilização. Os valores de resistência à compressão simples e de sucção tenderam a crescer com o aumento da massa específica aparente seca do solo e com a redução do teor de umidade. A resistência foi correlacionada com a sucção e com a massa específica aparente seca para os ensaios com teor de umidade constante e com a sucção e o teor de umidade para os ensaios com massa específica aparente seca constante. Os ângulos \'fi\'b que relacionam o aumento da resistência com a sucção variaram dependendo da forma de determinação e foram maiores quando determinados diretamente a partir da resistência não drenada do que quando determinados a partir da proposta de Fredlund et al. (1978). / The purpose this study was to measure the suction with high capacity tensiometer (HCT), placed at the bottom of the sample, during shear strength tests on a compacted soil. Three kinds of shear strength tests were performed on the sample in different conditions of saturation: triaxial consolidated drained in saturated condition, triaxial consolidated undrained with constant water content and unconfined compression in unsaturated condition. To assess the development of the suction and its influence on the shear strength of a compacted soil, the unconfined compression tests were performed in a series of repeatability and the others with variation of the dry density and water content of the sample. In all unconfined compression tests, the HCT recorded increase of suction until 3% axial deformation, approximately, from where the suction tended to stabilized. The values of compressive strength and suction increased with higher dry densities and lower water contents. Firstly, the shear strength was correlated with suction and the dry density, for constant water content tests. In sequence, it was correlated with suction and the water content for constant dry density tests. The \'fi\'b angle, that relates the increase of the strength with suction, varied depending of determination method. Its values were higher when directly determined from the undrained strength than when determined from the model presented by Fredlund et al. (1978).