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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

Applications of monolithic fiber interferometers and actively controlled fibers

Rugeland, Patrik January 2013 (has links)
The objective of this thesis was to develop applications of monolithic fiber devices and actively controlled fibers. A special twin-core fiber known as a ‘Gemini’ fiber was used to construct equal arm-length fiber interferometers, impervious to temperature and mechanical perturbations. A broadband add/drop multiplexer was constructed by inscribing fiber Bragg gratings in the arms of a Gemini Mach-Zehnder interferometer. A broadband interferometric nanosecond switch was constructed from a micro-structured Gemini fiber with incorporated metal electrodes. Additionally, a Michelson fiber interferometer was built from an asymmetric twin-core fiber and used as a high-temperature sensor. While the device could be readily used to measure temperatures below 300 °C, an annealing process was required to extend the range up to 700 °C. The work included development, construction and evaluation of the components along with numerical simulations to estimate their behaviors and to understand the underlying processes. The thesis also explored the use of electrically controlled fibers for filtering in the microwave domain. An ultra-narrow phase-shifted fiber Bragg grating inscribed in a fiber with internal electrodes was used as a scanning filter to measure modulation frequencies applied to an optical carrier. A similar grating was used inside a dual-wavelength fiber laser cavity, to generated tunable microwave beat frequencies. The studied monolithic fiber interferometers and actively controlled fibers provide excellent building blocks in such varied field as in microwave photonics, telecommunications, sensors, and high-speed switching, and will allow for further applications in the future. / Syftet med denna avhandling var att utveckla tillämpningar av monolitiska fiber komponenter samt aktivt kontrollerbara fiber. En speciell tvillingkärnefiber, även kallad ’Geminifiber’ användes för att konstruera fiber interferometrar med identisk armlängd som ej påverkas av termiska och mekaniska variationer. En bredbanding utbytarmultiplexor konstruerades genom att skriva in fiber Bragg gitter inuti grenarna på en Gemini Mach-Zehnder interferometer. Geminifibrer med interna metallelektroder användes för att konstruera en bredbandig nanosekundsnabb interferometrisk fiberomkopplare. Därtill användes en tvillingkärnefiber som en hög-temperatursensor. Även om komponenten direkt kan användas upp till 300 °C, måste den värmebehandlas för att kunna användas upp till 700 °C. Arbetet har innefattat utveckling, konstruktion och utvärdering av komponenterna parallellt med numeriska simuleringar för att analysera deras beteenden samt få insikt om de underliggande fysikaliska processerna. Avhandlingen behandlar även tillämpningar av en elektriskt styrbar fiber för att filtrera radiofrekvenser. Ett ultrasmalt fasskiftat fiber Bragg gitter skrevs in i en fiber med interna elektroder och användes som ett svepande filter för att mäta modulationsfrekvensen på en optisk bärfrekvens. Ett liknande gitter användes inuti en laserkavitet för att generera två olika våglängder samtidigt. Dessa två våglängder användes sedan för att generera en svävningsfrekvens i mikrovågsbandet. De undersökta monolitiska fiberinterferometrarna och de aktivt styrbara fibrerna erbjuder en utmärkt byggsten inom så pass skiljda områden som Mikrovågsfotonik, Telekommunikation, Sensorer samt Höghastighets-omkopplare och bör kunna användas inom många olika tillämpningar i framtiden. / <p>QC 20130226</p>
122

Debonding failure of fiber reinforced polymers

Sharma, Bhavna January 2006 (has links)
Thesis (M.S.)--University of Hawaii at Manoa, 2006. / Includes bibliographical references (leaves 94-97). / xi, 97 leaves, bound ill. (some col.) 29 cm
123

Processing and characterization of continuous fiber ceramic nanocomposites by preceramic polymer pyrolysis

Gudapati, Vamshi Mohan January 2005 (has links)
Thesis (M.S.)--University of Hawaii at Manoa, 2005. / Includes bibliographical references (leaves 56-61). / xi, 61 leaves, bound ill. 29 cm
124

A fibre optic light scattering system /

Suparno. Unknown Date (has links)
Thesis (MAppSc)--University of South Australia, 1994
125

An examination of crack growth in wood-FRP bonds /

Desjarlais, Justin J., January 2007 (has links) (PDF)
Thesis (M.S.) in Civil Engineering--University of Maine, 2007. / Includes vita. Includes bibliographical references (leaves 117-122).
126

Wavelength division multiplexing technology and systems /

Srinivas, B. S., January 1990 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1990. / Vita. Abstract. Includes bibliographical references (leaves 72-75). Also available via the Internet.
127

Theoretical and numerical investigation of the physics of microstructured optical fibres /

Kuhlmey, Boris T. January 2004 (has links)
Thesis (Ph. D.)--School of Physics, Faculty of Science, University of Sydney, 2004. (In conjunction with: Université de Droit, d'Économie et des Sciences d'Aix-Marseille (Aix Marseille III)). / Bibliography: leaves 196-204.
128

Tunnel filters and optical amplifiers for use in fiber optic communication systems /

Raad, Bechara, January 1991 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1991. / Vita. Abstract. Includes bibliographical references (leaves 103-105). Also available via the Internet.
129

Design guidelines for FRP honeycomb sandwich bridge decks

Zou, Bin, January 1900 (has links)
Thesis (Ph. D.)--West Virginia University, 2008. / Title from document title page. Document formatted into pages; contains xiv, 174 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 170-174).
130

Theoretical and numerical investigation of the physics of microstructured optical fibres

Kuhlmey, Boris T. January 2004 (has links)
Thesis (Ph. D.)--University of Sydney, 2004. / Title from title screen (viewed 14 May 2008). Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the School of Physics, Faculty of Science in conjunction with: Université de Droit, d'Économie et des Sciences d'Aix-Marseille (Aix Marseille III). Includes bibliographical references. Also available in print form.

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