A sensing method that can monitor metallic structures continuously would eventually produce safer metallic structures as well as a more efficient and economic way to monitor corrosion. A secondary focus of this research is the implementation of a fiber optic sensor to measure refractive indices of unknown solutions. The surface plasmon sensor, interrogated with white light resulted in attenuations of light at different wavelengths when solutions of different refractive indices were introduced. This sensor has been shown to respond to the three configurations of polished single mode and multimode, as well as the unpolished multimode sensors. The sensitivity calculated was comparable with the sensitivity of the Kretschmann arrangement The transmissive aluminum-clad fiber sensor was shown to be effective in providing a response to the process of corrosion. Varying lengths of aluminum-clad fiber was spliced to acrylate multimode fiber and different wavelengths of sources were used to test the sensor in a bath of NaOH. The results were similar and reproducible. A tapered sensor configuration was attempted and proved to be very useful. / Master of Science

Over the past decade, fiber optic strain sensors have begun to transition from use in laboratory research to commercial sector applications. This transition is somewhat hindered due to the high cost associated with many optical components required for fiber optic-based sensing systems. Multiplexing systems for fiber optic sensors are one approach to reducing the per-channel cost of fiber optic sensor implementation, however, in many applications, on-line monitoring of sensor elements is not required and the periodical addressing of sensor elements is acceptable. Commercially available fiber optic strain sensor systems are now available which support periodical sensor addressing by providing absolute information about the strain state of the sensor. A post-damage inspection fiber optic sensor design which employs a thick metal coating to retain information regarding the strain history of a sensor is demonstrated. Additionally demonstrated is a corrosion sensing technique which exploits the residual strain retention of the post-damage inspection sensor. Finally, the temperature sensing properties of the metal-coated sensor is investigated. / Master of Science

Spread spectrum techniques offer an alternate solution to the urgency for distributed optical fiber sensors. These techniques are based on the properties of pseudorandom sequences that have triangular autocorrelation functions with peaks only at regions of no delay. This affords an opportunity to give the desired signal a power advantage over many types of interference and noise. A study in employing spread spectrum techniques for multiplexing optical fiber sensors is presented. A mathematical analysis of the system is conducted with due consideration given to performance issues. Simulations in software are conducted to characterize system performance. Hardware developed for this project operates at over 1 Mbps and is capable of simultaneously monitoring four sensors. Real time experiments conducted on these multiplexed sensors affirm the technical feasibility of the system. Configurations for viable applications of the system are also suggested. / Master of Science

Thesis (M.S.)--Brigham Young University. Dept. of Mechanical Engineering, 2003. / Includes bibliographical references (p. 87-89).

Thesis (M.S.)--Mississippi State University. Department of Chemistry. / Title from title screen. Includes bibliographical references.

Not available / text

Thesis (M.Eng.)--University of Wollongong, 2006. / Typescript. Includes bibliographical references: leaf 101-106.

Thesis (M.S.) -- Mississippi State University. Department of Physics and Astronomy. / Title from title screen. Includes bibliographical references.

Thesis (Ph. D.)--University of Texas at Austin, 2003. / Vita. Includes bibliographical references. Available also from UMI Company.

Thesis (Ph. D.)--University of Texas at Austin, 1997. / Vita. Includes bibliographical references (leaves 188-199). Available also in a digital version from Dissertation Abstracts.