Physical Sciences and Mathematics Commons^™

Physical Unclonable Function Techniques Applied For Digital Hardware Protection, Anthony Barrera

Dissertations and Theses

"Privacy is an important property that is growing harder to keep as people develop new ways to steal information from users on their computers. Software alone cannot ensure privacy since an infected system is untrustworthy. This paper presents several challenges malware brings that can be solved by using an external processor. Techniques such as keystroke encryption and message authentication can be used to protect users from having their passwords and other private data stolen. To take advantage of the external hardware, a physical unclonable function can be used to generate private keys without the need for storing them in memory. …

Discrete Transforms With Good Time-Frequency And Spatial-Frequency Localization, David Chisholm

Dissertations and Theses

Discrete orthonormal time-frequency basis functions are described and used for both analysis and synthesis of complex-valued signals. We derive expressions for complex-valued expansion coefficients in time-frequency lattices in the discrete one dimensional case. This derivation is based on Professor I. Gertner's previous construction of a complete orthonormal set of basis functions well localized in the temporal-spatial-frequency domain in the continuous case. We describe how these can be generalized to any number of dimensions. Example applications are presented in one and two dimensions. Three dimensional basis functions are visualized and discussed. Finally, a full a Matlab implementation of this work is …

Uv-Visible Microscope Spectrophotometric Polarization And Dichroism With Increased Discrimination Power In Forensic Analysis, Dale Kevin Purcell

All Open Access Legacy Dissertations and Capstone Projects

Microanalysis of transfer (Trace) evidence is the application of a microscope and microscopical techniques for the collection, observation, documentation, examination, identification, and discrimination of micrometer sized particles or domains. Microscope spectrophotometry is the union of microscopy and spectroscopy for microanalysis. Analytical microspectroscopy is the science of studying the emission, reflection, transmission, and absorption of electromagnetic radiation to determine the structure or chemical composition of microscopic-size materials. Microscope spectrophotometry instrument designs have evolved from monochromatic illumination which transmitted through the microscope and sample and then is detected by a photometer detector (photomultiplier tube) to systems in which broad-band (white light) illumination …

Energy Of The Quasi-Free Electron In Repulsive Atomic And Molecular Fluids, Yevgeniy Lushtak

Dissertations, Theses, and Capstone Projects

The ability to predict accurately the energy V₀(ρ) of the quasi-free electron along the entire density (ρ) range of a supercritical fluid has applications in determining the ideal thermodynamic conditions for chemical reactions involving charged species. The previously established field ionization method of extracting V₀(ρ) from the fluid density dependent shift Δ(ρ) in the ionization energy of a dopant molecule has led to the discovery of a novel effect on V₀(ρ) occurring near the critical isotherm of the fluid. Unfortunately this method has limitations in determining V₀(ρ) in fluids with low critical …

3d Hallway Modeling Using A Single Image, Gregory M. Olmschenk

Dissertations and Theses

"Real-time, low-resource corridor reconstruction using a single consumer grade RGB camera is a powerful tool for allowing a fast, inexpensive solution to indoor mobility of a visually impaired person or a robot. The perspective and known geometry of a corridor is used to extract the important features of the image and create a 3D model from a single image. Multiple 3D models can be combined to increase confidence and provide a global 3D model. This paper presents our results on 3D corridor modeling using single images. First a simple but effective 3D corridor modeling approach is introduced which makes very …

Supercharging: An Investigation Into The Effects Of External Amino Acid Residue Charge On The Solubility And Internal Electric Character Of Bound Ligands In A Heme-Binding De Novo-Designed Protein, Cooper French

Dissertations and Theses

De novo protein design offers many interesting prospects both as a means to better understand natural protein dynamics and as a potential resource in biomedical and industrial applications. In this work I describe the modification of a simple, well-characterized heme-binding protein by altering side chain residue identities on the hydrophilic surface of the protein to produce variants with a range of net external charges. These charge modifications had a significant impact on nearly every measurable character of the protein. This work establishes the hard limits of supercharging within our experimental protein scaffold system, demonstrating that excessive positive charge increased the …

Theoretical Methods For Blur-Correction In Electron And Soft X-Ray Microscopy, Joanna Klukowska

Dissertations, Theses, and Capstone Projects

The process of object reconstruction from projections is widely used in many fields. One of the applications is the reconstruction of biological specimens from two-dimensional projections in transmission electron microscopy and transmission x-ray microscopy. Various methods have been developed for correcting the blurring that occurs when the projections are obtained by a real instrument. As the attainable resolution increases, new issues become apparent and need to be taken into account in the imaging model. In this dissertation we concentrate on the point spread function and its impact on the quality and usefulness of the reconstructions from images obtained according to …

Dipolar Interactions, Long Range Order And Random Fields In A Single Molecule Magnet, Mn12-Acetate, Bo Wen

Dissertations, Theses, and Capstone Projects

In this thesis, I will present an experimental study of two single molecule magnets, Mn₁₂-ac and Mn₁₂-ac-MeOH. I will show that in both systems, the temperature dependence of the inverse susceptibility yields a positive intercept on the temperature axis (a positive Weiss temperature), implying the existence of a ferromagnetic phase at low temperature.

Applying a magnetic field in the transverse direction moves the Weiss temperature downward towards zero. This implies that the transverse field triggers mechanisms in the system that compete with the dipolar interaction and suppress the long-range ordering.

I will then show that the …