Retinoblastoma is the most common primary intraocular tumor in children. The first sign that is often reported by parents is the appearance of recurrent leukocoria (i.e., “white eye”) in recreational photographs. A quantitative definition or scale of leukocoria – as it appears during recreational photography – has not been established, and the amount of clinical information contained in a leukocoric image (collected by a parent) remains unknown. Moreover, the hypothesis that photographic leukocoria can be a sign of early stage retinoblastoma has not been tested for even a single patient. This study used commercially available software (Adobe Photoshop®) and standard color space conversion algorithms (operable in Microsoft Excel®) to quantify leukocoria in actual “baby pictures” of 9 children with retinoblastoma (that were collected by parents during recreational activities i.e., in nonclinical settings). One particular patient with bilateral retinoblastoma (“Patient Zero”) was photographed >7, 000 times by his parents (who are authors of this study) over three years: from birth, through diagnosis, treatment, and remission. This large set of photographs allowed us to determine the longitudinal and lateral frequency of leukocoria throughout the patient's life. This study establishes: (i) that leukocoria can emerge at a low frequency in early-stage retinoblastoma and increase in frequency during disease progression, but decrease upon disease regression, (ii) that Hue, Saturation and Value (i.e., HSV color space) are suitable metrics for quantifying the intensity of retinoblastoma-linked leukocoria; (iii) that different sets of intraocular retinoblastoma tumors can produce distinct leukocoric reflections; and (iv) the Saturation-Value plane of HSV color space represents a convenient scale for quantifying and classifying pupillary reflections as they appear during recreational photography.

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A smart phone camera based indoor guidance system to aid the visually impaired is presented. Most proposed systems for aiding the visually impaired with indoor navigation are not feasible for widespread use due to cost, usability, or portability. We use a smart phone vision based system to create an indoor guidance system that is simple, accessible, inexpensive, and discrete to aid the visually impaired to navigate unfamiliar environments such as public buildings. The system consists of a smart phone and a server. The smart phone transmits pictures of the user's location to the server. The server processes the images and matches them to a database of stored images of the building. After matching features, the location and orientation of the person is calculated using 3D location correspondence data stored for features of each image. Positional information is then transmitted back to the smart phone and communicated to the user via text-to-speech. This thesis focuses on developing the vision technology for this unique application rather than building the complete system. Experimental results demonstrate the ability of the system to quickly and accurately determine the pose of the user in a university building.

With the retirement of the U.S. Space Shuttle fleet, the supply of extremely high quality water required for the Extravehicular Mobility Unit (EMU) space suit cooling on the International Space Station (ISS) will become a significant operational hardware challenge in the very near future. One proposed solution is the use of a filtration system consisting of a semipermeable membrane embedded with aquaporin proteins, a special class of transmembrane proteins that facilitate passive, selective transport of water in vivo. The specificity of aquaporins is such that only water is allowed through the protein structure, and it is this novel property that invites their adaptation for use in water filtration systems, specifically those onboard the ISS for the EMU space suit system. These proteins are also currently being developed for use in terrestrial filtration systems.