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2012

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Articles 1141 - 1170 of 12196

Full-Text Articles in Physical Sciences and Mathematics

Determining Stellar Velocity Dispersion In Active Galaxies: Is The [Oiii] Width A Valid Surrogate?, Kelsi Flatland Dec 2012

Determining Stellar Velocity Dispersion In Active Galaxies: Is The [Oiii] Width A Valid Surrogate?, Kelsi Flatland

Physics

The tight empirical relation between the stellar velocity dispersion (sigma) of the bulge and the mass of the supermassive black hole (BH) at its center indicates a close connection between galactic evolution and BH growth. The evolution of this relation with cosmic time provides valuable clues to its origin. While the mass of the BH can be easily estimated using the Doppler broadening of the Hbeta emission line in type I active galactic nuclei (AGNs), measuring sigma simultaneously is challenging, since the nuclear emission outshines the host galaxy. Thus, it is highly desirable to find an alternative way to estimate …


Faunal Distribution And Relative Abundance In A Silurian (Wenlock) Pinnacle Reef Complex - Ray Reef, Macomb County, Michigan, Jennifer L. Trout Dec 2012

Faunal Distribution And Relative Abundance In A Silurian (Wenlock) Pinnacle Reef Complex - Ray Reef, Macomb County, Michigan, Jennifer L. Trout

Masters Theses

Niagaran (Silurian) reefs are important sources of hydrocarbons in the Michigan Basin. In addition, some of these reservoirs have been used for gas storage and may be potential CO2 sequestration sites.

Despite extensive research on Niagaran reefs, most studies concerning faunal abundance and distribution have been qualitative studies conducted by paleontologists with an emphasis on taxonomy, paleoecology, and evolution.

This study is the first quantitative study of relative abundance and general distribution of fauna throughout a single Wenlock reef located in the southern trend of the Michigan Basin. This study will build on previous work done by WMU students and …


Characterizing The Internal Architecture Of Upper Bone Spring Limestone Turbidites And Mass-Transport Deposits (Mtds) Utilizing High-Resolution Image Log Technology, Jason J. Asmus Dec 2012

Characterizing The Internal Architecture Of Upper Bone Spring Limestone Turbidites And Mass-Transport Deposits (Mtds) Utilizing High-Resolution Image Log Technology, Jason J. Asmus

Masters Theses

Characterization of reservoir scale (less than 1 meter thick) turbidites and mass-transport deposits (MTDs) using conventional subsurface data is complex, due to millimeter-centimeter scale architectural heterogeneity exhibited by these deposits.

Limited studies of the Bone Spring carbonate turbidites and MTDs within the Delaware Basin subsurface emphasized the use of conventional wire-line log and seismic data to evaluate reservoir potential of such strata. As a result, limited resolution offered by these data sets do not allow for accurate characterization of reservoir, and sub-reservoir scale, architectural and compositional variations.

The present investigation integrates high-resolution (centimeter scale) electrical borehole image logs with conventional …


Nnll Resummation For W-Boson Production At Large Pt, Nikolaos Kidonakis, Richard J. Gonsalves Dec 2012

Nnll Resummation For W-Boson Production At Large Pt, Nikolaos Kidonakis, Richard J. Gonsalves

Faculty Articles

We present new results for W-boson production at large transverse momentum at the LHC and the Tevatron. The contribution of soft-gluon corrections is derived from NNLL resummation and added to the exact NLO result. Numerical results and their uncertainties for the approximate NNLO W-boson transverse momentum distributions are derived and compared to recent data from the LHC.


Probabilistic Approach To Modeling Lava Flow Inundation: A Lava Flow Hazard Assessment For A Nuclear Facility In Armenia, Laura J. Connor, Charles B. Connor, Khachatur Meliksetian, Ivan Savov Dec 2012

Probabilistic Approach To Modeling Lava Flow Inundation: A Lava Flow Hazard Assessment For A Nuclear Facility In Armenia, Laura J. Connor, Charles B. Connor, Khachatur Meliksetian, Ivan Savov

School of Geosciences Faculty and Staff Publications

Probabilistic modeling of lava flow hazard is a two-stage process. The first step is an estimation of the possible locations of future eruptive vents followed by an estimation of probable areas of inundation by lava flows issuing from these vents. We present a methodology using this two-stage approach to estimate lava flow hazard at a nuclear power plant site near Aragats, a Quaternary volcano in Armenia.


Combating Forced Labour And Human Trafficking In Africa: The Role Of Endogenous And Exogenous Forces, Ambe J. Njoh, Elizabeth N.M. Ayuk-Etang Dec 2012

Combating Forced Labour And Human Trafficking In Africa: The Role Of Endogenous And Exogenous Forces, Ambe J. Njoh, Elizabeth N.M. Ayuk-Etang

School of Geosciences Faculty and Staff Publications

It is widely believed that indigenous culture and tradition are at the root of the human trafficking and forced labour problem in Africa. Adherents to this viewpoint also claim that endogenous as opposed to exogenous forces impede efforts to eradicate the problem. This study employed a loglinear regression model to test the tenability of this claim. It hypothesized an inverse association between indigenous culture/tradition and efforts to combat human trafficking. The hypothesis was rejected. It is shown that anti-trafficking initiatives are less successful where indigenous tradition is dominated, or has been usurped, by imported cultural practices.


Lower Aptian Ammonite And Carbon Isotope Stratigraphy In The Eastern Prebetic Domain (Betic Cordillera, Southeastern Spain), J. A. Moreno-Bedmar, M. Company, J. Sandoval, J. M. Tavera, T. Bover-Arnal, R. Salas, G. Delanoy, Florentin J. Maurrasse Dr., R. Martinez Dec 2012

Lower Aptian Ammonite And Carbon Isotope Stratigraphy In The Eastern Prebetic Domain (Betic Cordillera, Southeastern Spain), J. A. Moreno-Bedmar, M. Company, J. Sandoval, J. M. Tavera, T. Bover-Arnal, R. Salas, G. Delanoy, Florentin J. Maurrasse Dr., R. Martinez

Department of Earth and Environment

Major global palaeobiologic and palaeoenvironmental changes occurred during the Early Aptian. Precise dating and timing of the different events is crucial to determine possible cause-effect relationships between them. In this regard, the combination of biostratigraphic and chemostratigraphic data can provide a very useful tool for time control. So far attempts to correlate the Lower Aptian carbon isotope record and the ammonite zonation yielded contradictory conclusions. In this paper, we present the results of an integrated analysis of the ammonite stratigraphic distribution and highresolution carbon isotope profiles from Lower Aptian sections of the eastern Prebetic Domain (Betic Cordillera, southeastern Spain). We …


Volatile Memory Message Carving: A "Per Process Basis" Approach, Aisha Ibrahim Ali-Gombe Dec 2012

Volatile Memory Message Carving: A "Per Process Basis" Approach, Aisha Ibrahim Ali-Gombe

University of New Orleans Theses and Dissertations

The pace at which data and information transfer and storage has shifted from PCs to mobile devices is of great concern to the digital forensics community. Android is fast becoming the operating system of choice for these hand-held devices, hence the need to develop better forensic techniques for data recovery cannot be over-emphasized. This thesis analyzes the volatile memory for Motorola Android devices with a shift from traditional physical memory extraction to carving residues of data on a “per process basis”. Each Android application runs in a separate process within its own Dalvik Virtual Machine (JVM) instance, thus, the proposed …


Modeling Energy Production Of Solar Thermal Systems And Wind Turbines For Installation At Corn Ethanol Plants, Elizabeth Ehrke Dec 2012

Modeling Energy Production Of Solar Thermal Systems And Wind Turbines For Installation At Corn Ethanol Plants, Elizabeth Ehrke

Theses and Dissertations

Nearly every aspect of human existence relies on energy in some way. Most of this energy is currently derived from fossil fuel resources. Increasing energy demands coupled with environmental and national security concerns have facilitated the move towards renewable energy sources. Biofuels like corn ethanol are one of the ways the U.S. has significantly reduced petroleum consumption. However, the large energy requirement of corn ethanol limits the net benefit of the fuel. Using renewable energy sources to produce ethanol can greatly improve its economic and environmental benefits. The main purpose of this study was to model the useful energy received …


Fundamental And Applied Studies Of Metal Ion Extraction By Crown Ethers Into Imidazolium-Based Room Temperature Ionic Liquids, Cory Hawkins Dec 2012

Fundamental And Applied Studies Of Metal Ion Extraction By Crown Ethers Into Imidazolium-Based Room Temperature Ionic Liquids, Cory Hawkins

Theses and Dissertations

Growing recognition of the extraordinary physicochemical properties and unique solvation environment afforded by ionic liquids (ILs) has drawn increasing attention to these solvents as media for chemical separations. Until recently, little was known about how ionic liquids behave as solvents in this application, particularly in the extraction of ionic solutes such as metal ions. In contrast to the single pathway observed using molecular diluents (i.e., neutral complex extraction), metal ion extraction in these systems has been shown to proceed through as many as three competing pathways over a wide range of conditions. Despite this added complexity, the favorable physicochemical characteristics …


Interpreting The Paleoenvironmental Context Of Marine Shales Deposited During The Cambrian Radiation: Global Insights From Sedimentology, Paleoecology, And Geochemistry, Tristan Kloss Dec 2012

Interpreting The Paleoenvironmental Context Of Marine Shales Deposited During The Cambrian Radiation: Global Insights From Sedimentology, Paleoecology, And Geochemistry, Tristan Kloss

Theses and Dissertations

Many Cambrian marine shales are traditionally thought to have been deposited under dysoxic or anoxic conditions based upon interpretations of sedimentological and ichnological fabrics. Recently a number of geochemical studies have suggested the opposite, that some Cambrian marine shales were deposited under slightly oxic to well-oxygenated conditions. Despite the significant implications redox conditions have for the paleoenvironment, paleoecology, and taphonomy of Cambrian shales, rarely are these disparate sedimentological and geochemical approaches combined for direct comparisons in a singular study of Cambrian shales. A multidisciplinary approach is used here, combining sedimentological, paleoecological, and geochemical approaches, for re-interpreting the paleoenvironmental conditions of …


Mitochondrial Targeting In Photodynamic Therapy. Metabolic And Drug Structure Requirements For Specific Mitochondrial Localization. A Pilot Investigation, Melissa Rhea Pergande Dec 2012

Mitochondrial Targeting In Photodynamic Therapy. Metabolic And Drug Structure Requirements For Specific Mitochondrial Localization. A Pilot Investigation, Melissa Rhea Pergande

Theses and Dissertations

Photodynamic therapy (PTD) has shown promise in the treatment of certain types of cancer (Davis et al. 1985, Chen 1988). One appealing strategy under consideration to selectively target tumor cells in PDT is that of mitochondrial targeting (Chen 1988, Chen 1989). The concept of mitochondrial targeting has its origin in the pioneering observation by Chen and colleagues that an enhanced mitochondrial transmembrane potential (ΔΨmito) is a prevalent tumor cell phenotype (Davis et al. 1985, Chen 1988). Because the plasma transmembrane potential is negative on the inner side of the cell, and the mitochondrial transmembrane potential is negative on the matrix …


Ecological Interactions Affecting Diatom Climate Reconstructions In Prairie Saline Lakes Of The Northern Great Plains (Usa), Courtney R. Wigdahl Dec 2012

Ecological Interactions Affecting Diatom Climate Reconstructions In Prairie Saline Lakes Of The Northern Great Plains (Usa), Courtney R. Wigdahl

Electronic Theses and Dissertations

Sedimentary diatom profiles from saline lakes are frequently used to reconstruct lakewater salinity as an indicator of drought. However, diatom-inferred salinity reconstructions (DI-salinity) from geographically-close sites in the Great Plains (USA) have yielded disparate results. Here, I explore how within-lake ecological processes, such as physical changes in lake habitat and zooplankton grazing pressure, may affect the accuracy of diatom-based salinity reconstructions. I examined how relationships differed among drought, lake-level change, and diatom community structure over the last century by developing three-dimensional models of planktic:benthic habitat (P:B) relationships with lake level change. I explored the potential for zooplankton grazing influence by …


Part I. The First Enantiospecific, Stereospecific Total Synthesis Of The Indole Alkaloid Ervincidine. Part Ii. The Synthesis Of Alpha 5 Subtype Selective Ligands For Gaba(A) /Benzodiazepine Receptors, Sundari K. Rallapalli Dec 2012

Part I. The First Enantiospecific, Stereospecific Total Synthesis Of The Indole Alkaloid Ervincidine. Part Ii. The Synthesis Of Alpha 5 Subtype Selective Ligands For Gaba(A) /Benzodiazepine Receptors, Sundari K. Rallapalli

Theses and Dissertations

Part I. The first enantiospecific, stereospecific total synthesis of ervincidine 89 has been accomplished from commercially available D-(+)-tryptophan 37 which has served both as the chiral auxiliary and the starting material. Moreover, this is the first synthesis which unequivocally sets the stereochemistry of the hydroxyl group at C-6 in sterospecific fashion, as well as the C-16 hydroxy methyl group. The stereospecific conversion of D-(+)-tryptophan 37 into the key template (−)-Na-H, Nb-benzyl tetracyclic ketone 49 via the asymmetric Pictet-Spengler reaction (600 gram scale) and Dieckmann cyclization on multi-hundred gram scale was reduced to only two reaction vessels. The optically active tetracyclic …


The Application Of Tomographic Reconstruction Techniques To Ill-Conditioned Inverse Problems In Atmospheric Science And Biomedical Imaging, Vern Philip Hart Ii Dec 2012

The Application Of Tomographic Reconstruction Techniques To Ill-Conditioned Inverse Problems In Atmospheric Science And Biomedical Imaging, Vern Philip Hart Ii

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Tomography is an imaging technique in which 3D models of objects are created from several 2D projections viewed at different angles. When the number of available projections is limited, the resulting data are said to be sparse. This restriction is often a direct result of the imaging geometry used to acquire the data. One-sided views and a small number of receivers can reduce the range of available projections, which makes the object more difficult to reconstruct. Approximate solutions to difficult imaging problems can be obtained using a class of iterative algorithms known as the algebraic reconstruction techniques (ARTs). The presented …


Diffusion Of Software Features: An Exploratory Study, Ferdian Thung, David Lo, Lingxiao Jiang Dec 2012

Diffusion Of Software Features: An Exploratory Study, Ferdian Thung, David Lo, Lingxiao Jiang

Research Collection School Of Computing and Information Systems

New features are frequently proposed in many software libraries. These features include new methods, classes, packages, etc. These features are utilized in many open source and commercial software systems. Some of these features are adopted very quickly, while others take a long time to be adopted. Each feature takes much resource to develop, test, and document. Library developers and managers need to decide what feature to prioritize and what to develop next. As a first step to aid these stakeholders, we perform an exploratory study on the diffusion or rate of adoption of features in Java Development Kit (JDK) library. …


Common Garden Experiments Reveal Uncommon Responses Across Temperatures, Locations, And Species Of Ants, Shannon L. Pelini, Sarah E. Diamond, Heidi Maclean, Aaron M. Ellison, Nicholas J. Gotelli, Nathan J. Sanders, Robert R. Dunn Dec 2012

Common Garden Experiments Reveal Uncommon Responses Across Temperatures, Locations, And Species Of Ants, Shannon L. Pelini, Sarah E. Diamond, Heidi Maclean, Aaron M. Ellison, Nicholas J. Gotelli, Nathan J. Sanders, Robert R. Dunn

College of Arts and Sciences Faculty Publications

Population changes and shifts in geographic range boundaries induced by climate change have been documented for many insect species. On the basis of such studies, ecological forecasting models predict that, in the absence of dispersal and resource barriers, many species will exhibit large shifts in abundance and geographic range in response to warming. However, species are composed of individual populations, which may be subject to different selection pressures and therefore may be differentially responsive to environmental change. Asystematic responses across populations and species to warming will alter ecological communities differently across space. Common garden experiments can provide a more mechanistic …


The Effects Of Bison On Cattle Winter Range In The Henry Mountains Of South Central Utah: Resolving A Conflict, Ian M. Ware Dec 2012

The Effects Of Bison On Cattle Winter Range In The Henry Mountains Of South Central Utah: Resolving A Conflict, Ian M. Ware

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The American Bison in the Henry Mountains are one of the last free-roaming, genetically pure herds of bison remaining in North America. Over the last decade, the herd has used a cattle winter range during the summer and early fall, creating a conflict between the wildlife officials who manage the bison population, and Bureau of Land Management officials and local ranchers who manage the rangeland. At the heart of this conflict is the question of whether bison are negatively impacting the rangeland resource, potentially reducing the abundance of preferable plant species. Negative impacts could include reduced forage availability in the …


In Situ Measurements Of Electron-Beam-Induced Surface Voltage Of Highly Resistive Materials, Joshua Hodges Dec 2012

In Situ Measurements Of Electron-Beam-Induced Surface Voltage Of Highly Resistive Materials, Joshua Hodges

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Surface charging and subsequent electrostatic discharge due to interactions with the space environment is one of the primary concerns of spacecraft charging studies. Laboratory measurements of the evolution of surface voltages and dissipation currents under simulated space conditions are the primary method used to determine the response of key spacecraft materials to diverse incident fluxes. Increasing the database of information for the electronic properties of insulating materials can assist spacecraft designers in mitigating the harsh effects of the space environment.

The Utah State Materials Physics Group, with the funding of the NASA James Webb Space Telescope project and personnel support …


Space Plug-And-Play Architecture Networking: A Self-Configuring Heterogeneous Network Architecture, Jacob Holt Christensen Dec 2012

Space Plug-And-Play Architecture Networking: A Self-Configuring Heterogeneous Network Architecture, Jacob Holt Christensen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In spacecraft engineering, the time and money involved in satellite construction is largely spent on design and integration of custom hardware and software. These efforts are duplicated for nearly every satellite with little to no reuse between spacecraft. There is a huge potential for cost savings in removing the duplication of work. However, there is a lack of standardization in the spaceflight community, causing soaring costs and delayed schedules as each component of a spacecraft is individually designed and custom built.

The Air Force Research Laboratory (AFRL) has developed the Space Plug-and-Play Architecture (SPA) to address this problem. SPA provides …


Visual Data Mining Techniques For Functional Actigraphy Data: An Object-Oriented Approach In R, Abbass Sharif Dec 2012

Visual Data Mining Techniques For Functional Actigraphy Data: An Object-Oriented Approach In R, Abbass Sharif

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Actigraphy, a technology for measuring a subject's overall activity level almost continuously over time, has gained a lot of momentum over the last few years. An actigraph, a watch-like device that can be attached to the wrist or ankle of a subject, uses an accelerometer to measure human movement every minute or even every 15 seconds. Actigraphy data is often treated as functional data. In this dissertation, we discuss what has been done regarding the visualization of actigraphy data, and then we will explain the three main goals we achieved: (i) develop new multivariate visualization techniques for actigraphy data; (ii) …


Video Compressive Sensing With 3-D Wavelet And 3-D Noiselet, Dao Lam, Donald C. Wunsch Dec 2012

Video Compressive Sensing With 3-D Wavelet And 3-D Noiselet, Dao Lam, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

A new compressive video sampling method is investigated. as opposed to other video sampling methods for which processing is conducted on a single-frame basis, this method is applied on multiple frames of the video stream. by exploiting the extension of Wavelet to 3-D with the support of Noiselet 3-D and combining it with fast reconstruction algorithms, this framework produces successful results quickly while maintaining the quality of the video stream. Despite its simplicity, this new approach outperforms other sophisticated methods. © 2012 IEEE.


Coupling Right- And Left-Handed Photons Differently To Charged Matter, Brett David Altschul Dec 2012

Coupling Right- And Left-Handed Photons Differently To Charged Matter, Brett David Altschul

Faculty Publications

We consider a modification of electrodynamics in which right- and left-circularly polarized photons are coupled to charged sources differently. Even though photon helicity is a Lorentz invariant quantity, such a modification breaks Lorentz symmetry, as well as locality. The modified theory includes novel magnetic forces between perpendicular currents. Existing data can be used to constrain the modification at approximately a 2 x 10^(-3) level.


Long-Term Effects Of Rice Rotation, Tillage, And Fertility On Near-Surface Soil Carbon And Nitrogen Cycling, Jill Marie Motschenbacher Dec 2012

Long-Term Effects Of Rice Rotation, Tillage, And Fertility On Near-Surface Soil Carbon And Nitrogen Cycling, Jill Marie Motschenbacher

Graduate Theses and Dissertations

Rice (Oryza sativa L.)-based cropping systems are different from other row crops due to the flood-irrigation scheme used from about one month after planting to a few weeks prior to harvest. The frequent cycling between anaerobic (i.e., flooding during the growing season) and aerobic (i.e., generally, the remainder of the year) conditions can influence the rate of soil organic matter (SOM) decomposition, which can greatly influence carbon (C) and nitrogen (N) storage and sequestration in the soil over time. Therefore, a study was conducted on a silt-loam soil (fine, smectitic, thermic, Typic Albaqualf) at the Rice Research and Extension Center …


Evaluation Of The Effects Of Absorption Field Product Architecture Type On Effluent Dispersal And Soil Chemical Properties In A Profile-Limited Soil, Nina J.M. Prater Dec 2012

Evaluation Of The Effects Of Absorption Field Product Architecture Type On Effluent Dispersal And Soil Chemical Properties In A Profile-Limited Soil, Nina J.M. Prater

Graduate Theses and Dissertations

On-site wastewater treatment systems (OWTSs) are commonly used by households in areas of low population density to treat household wastewater and recycle it back to the environment. The traditional absorption field product used in OWTSs is a pipe-and-gravel architecture type, which has been used for decades and is the basis for most design regulations. However, new products of differing architecture types including chambers, polystyrene-aggregate, pipe-and-tire-chip, and gravel-less-pipe systems have recently become available. A three-year field study was conducted in Bethel Heights, AR to assess the performance of several newer products and to compare different architecture types to the traditional pipe-and-gravel …


Exploring The Surface Liquid And Lake Regions Of Titan With Laboratory Experimentation And Cassini Spacecraft Data, Felix Casimir Wasiak Dec 2012

Exploring The Surface Liquid And Lake Regions Of Titan With Laboratory Experimentation And Cassini Spacecraft Data, Felix Casimir Wasiak

Graduate Theses and Dissertations

The surface liquids and lake regions of Titan are studied utilizing three unique techniques, the results of which are reported in this dissertation. The development of a facility to simulate the surface conditions of Titan, and to conduct experiments on samples within that facility, brings an understanding of Titan's surface not possible through observation and modeling alone. The properties of this facility are presented, including conceptual methodology, design, implementation, performance, and experimental results. The facility, the main component of which is a simulation chamber, allows for Titan temperatures of 90 - 94 K and a 1.5 bar N2 atmosphere. The …


Penetration Forces For Subsurface Regolith Probes, Ahmed Elshafie Dec 2012

Penetration Forces For Subsurface Regolith Probes, Ahmed Elshafie

Graduate Theses and Dissertations

Investigating planetary bodies using penetrometers can provide detailed information about its history and evolution. An estimation of subsurface density and porosity can be made from the shape of the penetration curve. Using penetrometers mounted on planetary platforms could be challenging due to the uncertainty of the subsurface composition and since the maximum allowed force for penetration is the weight of the lander or rover on the surface. Estimation of penetration forces can provide a reliable constraint on the maximum reachable depth without endangering the whole mission. Therefore, knowledge of the required penetration force to specific depths can be helpful in …


Plasmonic And Photonic Designs For Light Trapping In Thin Film Solar Cells, Liming Ji Dec 2012

Plasmonic And Photonic Designs For Light Trapping In Thin Film Solar Cells, Liming Ji

Graduate Theses and Dissertations

Thin film solar cells are promising to realize cheap solar energy. Compared to conventional wafer cells, they can reduce the use of semiconductor material by 90%. The efficiency of thin film solar cells, however, is limited due to insufficient light absorption. Sufficient light absorption at the bandgap of semiconductor requires a light path more than 10x the thickness of the semiconductor. Advanced designs for light trapping are necessary for solar cells to absorb sufficient light within a limited volume of semiconductor. The goal is to convert the incident light into a trapped mode in the semiconductor layer.

In this dissertation, …


Prehistoric Human Ecodynamics In The Rub Al-Khali Desert: Results Of Remote Sensing And Excavations In Dubai, United Arab Emirates, Jason T. Herrmann Dec 2012

Prehistoric Human Ecodynamics In The Rub Al-Khali Desert: Results Of Remote Sensing And Excavations In Dubai, United Arab Emirates, Jason T. Herrmann

Graduate Theses and Dissertations

Archaeological investigations in the Emirate of Dubai, UAE conducted by the Dubai Department of Archaeology and the University of Arkansas demonstrate that the desert inland of the Oman Peninsula was occupied not only during the Arabian Neolithic (8000-4400 BC), when the region experienced a moist period referred to as the Holocene Climatic Optimum (HCO), but also during the more arid millennia following the decline of the HCO into the Christian Era. During this period, desert settlement clustered near a band of oases, in contrast to the more widespread spatial distribution of remains of nomadic pastoralists from the Neolithic. Excavations at …


Investigating The Sensitivity Of Goodness-Of-Fit Indices To Detect Measurement Invariance In The Bifactor Model, Jam Khojasteh Dec 2012

Investigating The Sensitivity Of Goodness-Of-Fit Indices To Detect Measurement Invariance In The Bifactor Model, Jam Khojasteh

Graduate Theses and Dissertations

A Monte Carlo simulation study was conducted to evaluate the sensitivities of five commonly used goodness-of-fit indices to detect metric invariance properties of the bifactor model. The fit indices that performed the best in terms of power were Gamma and Mc. In addition, Gamma, Mc, CFI, and RMSEA all held Type I error to a minimum. However, only Gamma and CFI are recommended to use in the bifactor model because the other GOF indices have cutoff values that are too large. For Gamma and CFI values of -.026 to -.045 and -.004 to -.009, respectively indicate a lack of metric …