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One of the most important methodological advances in the archaeology of the past quarter century is the use of Geographic Information System (GIS) in archaeological research. Within this time frame, GIS has evolved from an emergent geospatial technology with limited mapmaking capabilities to a technology of choice for cultural resource managers, planners, and academic archaeologists alike. This dissertation examines the evolutionary trajectory and impact of GIS in the discipline since its introduction, and its potential to support new applications of GIS-driven innovation in archaeological research. As part of this project, two separate studies were conducted. The first study assessed adoption and diffusion trends for the technology based on the published literature from 1987-2010 using bibliometric and content analysis. These results suggest that despite adoption reaching a critical mass point in 2003-2006, GIS use is still maturing, and emphasis continues to be on methodological refinements rather than theoretical advances. Many of the technical developments coincide with larger changes within computing and in the convergence of technologies and platforms within the GIS industry. Recent publications, however, indicate the emergence of a possibly new direction for archaeological research which relies more on computationally intensive rather than empirical methods of investigation, in effect blurring traditional distinctions between method and theory. The second study conducted as part of this project explores the implications of this phenomenon by developing and implementing an application within a GIS environment for knowledge discovery in databases. The objective was to explore the feasibility and efficacy of geographic data mining using current technologies and archaeological data standards, identify barriers to its implementation, and demonstrate a new course for GIS-driven innovation in the field. Various archaeological and environmental datasets from the Fort Wingate Depot Activity in western New Mexico, USA were selected, compiled, prepared, and analyzed as part of the case study. Logistic regression was combined with Weights-of-Evidence modeling to discover previously unknown but statistically significant relationships and patterns within the prehistoric and historic data. This study offers suggestions on both how to adapt old data to new technologies and how to adapt new technologies to new ways of thinking.

Genetic variation was examined in two endangered mussel species, Epioblasma brevidens and E. capsaeformis, and a common species Lampsilis fasciola, in the Clinch River, TN, by screening mitochondrial DNA (mtDNA) sequences and nuclear DNA microsatellites. These species use fish hosts with varying dispersal capabilities, ranging from low, moderate, and high, respectively. Patterns of mtDNA polymorphism exhibited different trends for long-term population sizes for each species during the Holocene (~10,000 ya to present); namely, E. brevidens has declined over time, E. capsaeformis has remained stable, and L. fasciola has expanded. Long-term effective population size (Ne) was smallest in E. brevidens, intermediate in E. capsaeformis, and highest in L. fasciola. Moderately diverged mtDNA lineages, perhaps indicative of secondary contact, were observed in E. brevidens and E. capsaeformis. High levels of gene flow (Nm) were estimated among demes of L. fasciola using traditional F-statistics and likelihood estimates of Nm, whereas such metrics were lower in E. brevidens and E. capsaeformis. Data are consistent with population dynamics and life history traits of each species and their fish hosts. Age, shell growth, and population demography of Epioblasma brevidens, E. capsaeformis, and Lampsilis fasciola were studied from 2004-2007 in a 32-km reach of the Clinch River, TN. Observed maximum age and length of E. brevidens was 28 y and 71.5 mm for males and 11 y and 56.6 mm for females; of E. capsaeformis, 12 y and 54.6 mm for males and 9 y and 48.6 mm for females; and of L. fasciola, 45 y and 91.3 mm for males and 13 y and 62.6 mm for females. For all three species, observed maximum age and length was greater among males than females. Estimated population size in this river reach was approximately 43,000 individuals for E. brevidens, 579,000 individuals for E. capsaeformis, and 30,000 individuals for L. fasciola. Mean recruitment y-1 of 1 y-old E. brevidens ranged from 7.1% to 20%, of E. capsaeformis from 4.0% to 32.4%, and of L. fasciola from 5.8% to 25.6%. Population growth rate y-1 was 24.9% for E. brevidens, 34.6% for E. capsaeformis, and -22.4% for L. fasciola. Mortality rates of females were higher than for males of E. capsaeformis and L. fasciola, but not E. brevidens. Juvenile mussels were collected but temporally and spatially variable in occurrence, and a significant component of the age-class structure of all three species. Recruitment was very high during 2006-2007 for E. capsaeformis and other species, likely due to low river discharges in the spring-summer of 2005-2007. Surplus individuals of E. brevidens and E. capsaeformis are currently available to conduct translocations for restoration purposes. Population modeling of Epioblasma brevidens and E. capsaeformis in the Clinch River was conducted to determine suitable harvest levels for translocation of sub-adults and adults, and to determine quantitative criteria for evaluating performance and recovery of extant and reintroduced populations. For both species, the recommended annual harvest was

The primary criteria for an analytical tool to meet to be effective in nanoscale science are high speed, ease of measurement, and simultaneous acquisition of multiple types of information. Even though the size of features that can be created in silicon using a commercialized nano-patterning process is down to 65 nm, techniques for analyzing structures with nanometer resolution and meeting the above criteria still need to be developed. Raman spectroscopy is an effective tool for the study of nano-structures due to its ability to observe the distribution of stress in samples while capturing the fingerprint spectra of chemical functionalities. The main drawbacks hindering the use of Raman spectroscopy for nano-analysis are the low signal intensity and the diffraction-limited resolution of current instruments. The strategy for overcoming the low intensity is to induce an enhancement in the electric field in the sample by placing it next to a roughened noble metal surface. With the aid of a thin noble metal layer, surface enhanced Raman scattering (SERS) spectra of films of polystyrene blends including different branched molecular architecture were acquired. These probe the composition within a depth of ~2 nm from the surface. The surface compositions gained using SERS were comparable to those gained from neutron reflectivity. To optimize the lateral resolution of SERS and to simultaneously access additional information such as surface topography, a Raman spectrometer and accompanying optics have been combined with a scanning probe microscope (SPM). The enhancement of the Raman signal on a very local, nanoscale level was realized by using the very small contact area between a noble metal layer on a SPM probe (tip) and a sample surface. Using a method based on such a combination, called scanning nano-Raman spectroscopy (SNRS), we have demonstrated Raman spectral imaging capability with ~20 nm lateral resolution with simultaneous topography measurement. For the successful application of SNRS to the analysis of silicon nano-structures, the contrast between the enhanced, localized signal and the far field signal has been maximized by optimizing the beam polarization. This optimized polarization was used to demonstrate an improvement in contrast by a factor of ~20 and a much better scanning capability than available with conventional polarization.

Power consumption has become a primary metric in the design of integrated circuits due to the pervasive use of embedded IC devices in a broad range of applications, from large server farms and personal computers to mobile, handheld and wireless devices. Due to technology scaling, leakage power has emerged as a significant source of power consumption, significantly increasing the power budget. Thus, the semiconductor industry is placing a great deal of time, money and energy into developing techniques to reduce not only leakage power, but active power as well. The work in this dissertation focuses on the power and robustness issues in scaled technologies, predominantly in the 65-nm regime. Approaches presented in this dissertation are intended for power reduction in advanced industrial technologies, while leaving performance unchanged. Several bus designs are introduced which significantly reduce not only the leakage power component of total power dissipation, but also dynamic power, which is still the chief component of the total power budget for nearly any given high performance integrated design. These bus design approaches reduce power consumption while having little to no effect on the performance of the bus system. Two of the bus designs sense changing transitions on the lines to adaptively respond to the current switching and data environment. This work also looks at reducing leakage power in general blocks of logic using improved power gating techniques. By creating intermediate sleep modes, the impact of power gated design can be broadened to further decrease leakage power. In a sense, the power gating methods that are developed in this dissertation are adaptive to the data environment in which they are used. Finally, three separate techniques are developed which increase the robustness of integrated circuits. Two of these designs adapt to the point in the process spread in which they were fabricated and give important feedback to the system so that it can also adapt to the operating environment. These techniques prove to be extremely useful in providing information to the system so that it can adaptively respond to process, voltage or temperature variations.

Time resolved spectroscopic techniques including Ultrafast Transient Absorption, Laser flash photolysis with UV-visible and infrared detection and modern quantum chemical calculations were used to directly observe and identify reactive intermediates involved in the photolysis of azido and diazo compounds. In this dissertation the photolysis of 8-azidoadenosine and its derivatives were studied in water and in buffer solutions. Using ultrafast spectroscopic techniques it was shown that the corresponding singlet nitrene undergoes a hydrogen shift to form a closed azaquinodimethane faster then it can relax to a triplet nitrene or react with biological target molecules in a photoaffinity labeling experiment. The spectroscopic characteristics of azaquinodimethane were determined using nanosecond laser flash photolysis in the UV-visible and IR regions. The lifetime of this species was estimated to be several minutes in the absence of good nucleophiles, and it is the species which forms adducts in cross-linking and photoaffinity labeling experiments via selective reactions with nucleophiles. Quantum chemical calculations were utilized to identify reactive intermediates produced upon photolysis. Implications of the results of this work on the interpretation of results obtained in photoaffinity labeling and cross-linking experiments are discussed. Ultrafast spectroscopy and nanosecond time resolved Laser Flash Photolysis methods were used to study the photochemistry of 3,5-dichloro 2-biphenyl azide in different solvents. The corresponding singlet nitrene was detected and corresponding spectroscopic characteristics were determined. The photochemistry of diphenyldiazomethane in series of alcohols solvent reveals the fastest known proton transfer reaction to a carbon atom. Studies performed using ultrafast transient absorption spectroscopy revealed the formation and decay of the benzhydryl carbocation. It was shown that benzhydryl carbocation is a short lived intermediate in neat alcohol solvents. Rates of protonation were measured directly and shown to correlate with solvation times in alcohols from methanol to 2-propanol. The rate-limiting step in the overall O-H insertion reaction was determined from a study of the kinetic isotope effect. Transient absorption actinometry measurements were performed on the femtosecond time scale and the contribution of the protonation channel to the O-H insertion reaction was estimated for several alcohols.