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2014

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Three-Dimensional Geomodeling To Identify Spatial Relations Between Lithostratigraphy And Porosity In The Karst Carbonate Biscayne Aquifer, Southeastern Florida, Richard Westcott Jan 2014

Three-Dimensional Geomodeling To Identify Spatial Relations Between Lithostratigraphy And Porosity In The Karst Carbonate Biscayne Aquifer, Southeastern Florida, Richard Westcott

Electronic Theses and Dissertations 2010 - 2019

In southeastern Florida, the majority of drinking water comes from the Biscayne aquifer. This aquifer is comprised of heterogeneous limestones, sandstones, sand, shell and clayey sand with zones of very high permeability. Visualizing the spatial variations in lithology, porosity and permeability of heterogeneous aquifers, like the Biscayne, can be difficult using traditional methods of investigation. Using the Roxar IRAP RMS software multi-layered 3D conceptual geomodels of the lithology, cyclostratigraphy and porosity were created in a portion of the Biscayne aquifer. The models were built using published data from borehole geophysical measurements, core samples, and thin sections. Spatial relations between lithology, …

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The Topology Of Archaeological Site Distributions: The Lacunarity And Fractality Of Prehistoric Oaxacan Settlements, Kelin Flanagan Jan 2014

The Topology Of Archaeological Site Distributions: The Lacunarity And Fractality Of Prehistoric Oaxacan Settlements, Kelin Flanagan

Electronic Theses and Dissertations 2010 - 2019

Survey is time-consuming and expensive. Therefore, it needs to be both effective and efficient. Some archaeologists have argued that current survey techniques are not effective (Shott 1985, 1989), but most archaeologists continue to employ these methods and therefore must believe they are effective. If our survey techniques are effective, why do simulations suggest otherwise? If they are ineffective, can we improve them? The answers to these practical questions depend on the topological characteristics of archaeological site distributions. In this study I analyze archaeological site distributions in the Valley of Oaxaca, Mexico, using lacunarity and fractal dimension. Fractal dimension is a …

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The Triangle Of Reflections, Jesus Torres Jan 2014

The Triangle Of Reflections, Jesus Torres

Electronic Theses and Dissertations 2010 - 2019

This thesis presents some results in triangle geometry discovered using dynamic software, namely, Geometer’s Sketchpad, and confirmed with computations using Mathematica 9.0. Using barycentric coordinates, we study geometric problems associated with the triangle of reflections T of a given triangle T, yielding interesting triangle centers and simple loci such as circles and conics. These lead to some new triangle centers with reasonably simple coordinates, and also new properties of some known, classical centers. Particularly, we show that the Parry reflection point is the common point of two triads of circles, one associated with the tangential triangle, and another with the …

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Spectral Evaluation Of Motion Compensated Adv Systems For Ocean Turbulence Measurements, Matthew Nicklas Egeland Jan 2014

Spectral Evaluation Of Motion Compensated Adv Systems For Ocean Turbulence Measurements, Matthew Nicklas Egeland

Electronic Theses and Dissertations 2010 - 2019

A motion compensated ADV system was evaluated to determine its ability to make measurements necessary for characterizing the variability of the ambient current in the Gulf Stream. The impact of IMU error relative to predicted turbulence spectra was quantified, as well as and the ability of the motion compensation approach to remove sensor motion from the ADV measurements. The presented data processing techniques are shown to allow the evaluated ADV to be effectively utilized for quantifying ambient current fluctuations from 0.02 to 1 Hz (50 to 1 seconds) for dissipation rates as low as 3x10-7. This measurement range is limited …

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Sparse And Low Rank Constraints On Optical Flow And Trajectories, Joel Gibson Jan 2014

Sparse And Low Rank Constraints On Optical Flow And Trajectories, Joel Gibson

Electronic Theses and Dissertations 2010 - 2019

In this dissertation we apply sparse constraints to improve optical flow and trajectories. We apply sparsity in two ways. First, with 2-frame optical flow, we enforce a sparse representation of flow patches using a learned overcomplete dictionary. Second, we apply a low rank constraint to trajectories via robust coupling. We begin with a review of optical flow fundamentals. We discuss the commonly used flow estimation strategies and the advantages and shortcomings of each. We introduce the concepts associated with sparsity including dictionaries and low rank matrices.

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The Impact And Effectiveness Of Capital Investments In The American Recovery And Reinvestment Act Of 2009: An Assessment Using Keynes Economic Theory, Vincent Byaruhanga Jan 2014

The Impact And Effectiveness Of Capital Investments In The American Recovery And Reinvestment Act Of 2009: An Assessment Using Keynes Economic Theory, Vincent Byaruhanga

Electronic Theses and Dissertations 2010 - 2019

The purpose of this study is to find out the effect of government spending on capital investments in the American Recovery and Reinvestment Act (ARRA) of 2009 on GDP and employment growth. This research utilized US quarterly data from 2003 QI to 2013 QII. In the first part the research used variables from the Keynes economic model and utilized two-stage least square analysis to assess the effect of government spending on GDP. The results from the regression analysis indicate that an increase of one dollar in government spending increases GDP by 1.569 dollars. The researcher found that the general government …

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Modeling And Simulating Interest Rates Via Time-Dependent Mean Reversion, Andrew Jason Dweck Jan 2014

Modeling And Simulating Interest Rates Via Time-Dependent Mean Reversion, Andrew Jason Dweck

Electronic Theses and Dissertations 2010 - 2019

The purpose of this thesis is to compare the effectiveness of several interest rate models in fitting the true value of interest rates. Up until 1990, the universally accepted models were the equilibrium models, namely the Rendleman-Bartter model, the Vasicek model, and the Cox-Ingersoll-Ross (CIR) model. While these models were probably considered relatively accurate around the time of their discovery, they do not provide a good fit to the initial term structure of interest rates, making them substandard for use by traders in pricing interest rate options. The fourth model we consider is the Hull-White one-factor model, which does provide …

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Modeling The Performance Of A Laser For Tracking An Underwater Dynamic Target, Thomas J. Dill Jan 2014

Modeling The Performance Of A Laser For Tracking An Underwater Dynamic Target, Thomas J. Dill

Electronic Theses and Dissertations 2010 - 2019

Options for tracking dynamic underwater targets using optical methods is currently limited. This thesis examines optical reflectance intensities utilizing Lambert’s Reflection Model and based on a proposed underwater laser tracking system. Numerical analysis is performed through simulation to determine the detectable light intensities based on relationships between varying inputs such as angle of illumination and target position. Attenuation, noise, and laser beam spreading are included in the analysis. Simulation results suggest optical tracking exhibits complex relationships based on target location and illumination angle. Signal to Noise Ratios are a better indicator of system capabilities than received intensities. Signal reception does …

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Mobile Docking Of Remus-100 Equipped With Usbl-Aps To An Unmanned Surface Vehicle: A Performance Feasibility Study, Mario Ii Miranda Jan 2014

Mobile Docking Of Remus-100 Equipped With Usbl-Aps To An Unmanned Surface Vehicle: A Performance Feasibility Study, Mario Ii Miranda

Electronic Theses and Dissertations 2010 - 2019

The overall objective of this work is to evaluate the ability of homing and docking an unmanned underwater vehicle (Hydroid REMUS 100 UUV) to a moving unmanned surface vehicle (Wave-Adaptive Modular Surface Vehicle USV) using a Hydroid Digital Ultra-Short Baseline (DUSBL) acoustic positioning system (APS), as a primary navigation source. An understanding of how the UUV can rendezvous with a stationary USV first is presented, then followed by a moving USV. Inherently, the DUSBL-APS is susceptible to error due to the physical phenomena of the underwater acoustic channel (e.g. ambient noise, attenuation and ray refraction). The development of an APS …

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Pattern Mining And Visualization For Molecular Dynamics Simulation, Xue Kong Jan 2014

Pattern Mining And Visualization For Molecular Dynamics Simulation, Xue Kong

Electronic Theses and Dissertations 2010 - 2019

Molecular dynamics is a computer simulation technique for expressing the ultimate details of individual particle motions and can be used in many fields, such as chemical physics, materials science, and the modeling of biomolecules. In this thesis, we study visualization and pattern mining in molecular dynamics simulation. The molecular data set has a large number of atoms in each frame and range of frames. The features of the data set include atom ID; frame number; position in x, y, and z plane; charge; and mass. The three main challenges of this thesis are to display a larger number of atoms …

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Optimal Chunk-Based Resource Allocation For Ofdma Systems With Multiple Ber Requirements, Tianzhou He Jan 2014

Optimal Chunk-Based Resource Allocation For Ofdma Systems With Multiple Ber Requirements, Tianzhou He

Electronic Theses and Dissertations 2010 - 2019

In wireless orthogonal frequency division multiple-access (OFDMA) standards, subcarriers are grouped into chunks and a chunk of subcarriers is made as the minimum allocation unit for subcarrier allocation. We investigate the chunk-based resource allocation for OFDMA downlink, where data streams contain packets with diverse bit-errorrate (BER) requirements. Supposing that adaptive transmissions are based on a number of discrete modulation and coding modes, we derive the optimal resource allocation scheme that maximizes the weighted sum of average user rates under the multiple BER and total power constraints. With proper formulation, the relevant optimization problem is cast as an integer linear program …

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Rain-Wind-Induced Cable Vibrations In Cable-Stayed Bridges, Oscar F. Calle Jan 2014

Rain-Wind-Induced Cable Vibrations In Cable-Stayed Bridges, Oscar F. Calle

Electronic Theses and Dissertations 2010 - 2019

This research is aimed at investigating and analyzing the rain-windinduced cable vibration phenomena experienced in cables of cable-stayed bridges and also the countermeasures employed by engineers to mitigate the large-amplitude vibration problem reported by various researchers around the world. In order to investigate the problem of the water rivulet creation at the top of the cable surface, a single-degree-of-freedom (SDOF) analytical model was developed and analyzed. This thesis studies the aerodynamic instability of cables in cable-stayed bridges by doing literature review of a typical in-situ test, developing a single degree-of-freedom (SDOF) analytical model, and an ANSYS finite element model. Furthermore, …

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Prognostic Copd Healthcare Management System, Piyush Jain Jan 2014

Prognostic Copd Healthcare Management System, Piyush Jain

Electronic Theses and Dissertations 2010 - 2019

Hospital readmission rates are considered to be an important indicator of quality of care because they may be a consequence of actions of commission or omission made during the initial hospitalization of the patient, or as a consequence of poorly managed transition of the patient back into the community. The negative impact on patient quality of life and huge burden on healthcare system have made reducing hospital readmissions a central goal of healthcare delivery and payment reform efforts. In this project, we will focus on COPD (Chronic Obstructive Pulmonary Disease) which is one of the leading causes of disability and …

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Leveled Flight Control Of An Unmanned Underwater Vehicle Operating In A Wave Induced Environment, Joshua J. Potesta Jan 2014

Leveled Flight Control Of An Unmanned Underwater Vehicle Operating In A Wave Induced Environment, Joshua J. Potesta

Electronic Theses and Dissertations 2010 - 2019

Autonomous Underwater Vehicle (AUV) depth control methods typically use a pressure sensor to measure the depth, which results in the AUV following the trajectory of the surface waves. Through simulations, a controller is designed for the Ocean Explorer AUV with the objective of the AUV holding a constant depth below the still water line while operating in waves. This objective is accomplished by modeling sensors and using filtering techniques to provide the AUV with the depth below the still water line. A wave prediction model is simulated to provide the controller with knowledge of the wave disturbance before it is …

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Predictive Modeling For Wellness, Pranitha Pulumati Jan 2014

Predictive Modeling For Wellness, Pranitha Pulumati

Electronic Theses and Dissertations 2010 - 2019

Wellness and healthy life are the most common concerns for an individual to lead a happy life. A web-based approach known as Wellness Scoring is being developed taking into people’s concerns for their health issues. In this approach, four different classifiers are being investigated to predict the wellness. In this thesis, we investigated four different classifiers (a probabilistic graphical model, simple probabilistic classifier, probabilistic statistical classification and an artificial neural network) to predict the wellness outcome. An approach to calculate wellness score is also addressed. All these classifiers are trained on real data, hence giving more accurate results. With this …

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Predicting The Flow & Noise Of A Rotor In A Turbulent Boundary Layer Using An Actuator Disk – Rans Approach, Armand C. Buono Jan 2014

Predicting The Flow & Noise Of A Rotor In A Turbulent Boundary Layer Using An Actuator Disk – Rans Approach, Armand C. Buono

Electronic Theses and Dissertations 2010 - 2019

The numerical method presented in this study attempts to predict the mean, non-uniform flow field upstream of a propeller partially immersed in a thick turbulent boundary layer with an actuator disk using CFD based on RANS in ANSYS FLUENT. Three different configurations, involving an infinitely thin actuator disk in the freestream (Configuration 1), an actuator disk near a wall with a turbulent boundary layer (Configuration 2), and an actuator disk with a hub near a wall with a turbulent boundary layer (Configuration 3), were analyzed for a variety of advance ratios ranging from J = 0.48 to J =1.44. CFD …

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Predictors Of Undergraduate Academic Success, Sheri L. Glick-Cuenot Jan 2014

Predictors Of Undergraduate Academic Success, Sheri L. Glick-Cuenot

Electronic Theses and Dissertations 2010 - 2019

This study attempted the answer to two primary questions: (a) Are strategic thinking skills possessed by college students prior to university matriculation related to their academic success in college, and (b) How does the predictive accuracy afforded by these skills compare to that from high school grade point average or standardized test scores?

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Martial Arts As A Markup Language, Thomas Vo Jan 2014

Martial Arts As A Markup Language, Thomas Vo

Electronic Theses and Dissertations 2010 - 2019

This thesis describes the modeling of Martial Arts as a markup language. Up until now Martial Arts has already been documented in books, videos, tradition and other methods. Though to represent Martial Arts knowledge consistently and uniformly in a digital era, we introduce the Martial Arts Markup Language (MAML), which is based on XML. Because XML provides a standardized, serializable and portable format, MAML also enables sharing among students, teachers and their peers across different platforms, media and networks. MAML provides the ability, with appropriate XML tools, to document a Martial Arts style in a structured way. To achieve this, …

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Chloride Penetration Into Concrete Structures Exposed To The Marine Atmosphere, Scott Thompson Shill Jan 2014

Chloride Penetration Into Concrete Structures Exposed To The Marine Atmosphere, Scott Thompson Shill

Electronic Theses and Dissertations 2010 - 2019

Chloride ions present in the marine atmosphere contained in marine aerosols is investigated for a relationship with chloride that accumulated into concrete. Chloride profiles are conducted on several concrete mixes containing fly ash, silica fume, and slag, with water to cementitious ratios of 0.35, 0.41, and 0.47. The chloride accumulation in concrete samples exposed to the environment is investigated with relation to the chloride deposition from the marine atmosphere measured via the wet candle test. Results indicate a possible relationship for the total accumulated chloride in the concrete with the accumulated chloride deposition (wet candle). Over the exposure periods, concrete …

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Average (Arithmetic Mean) Of Women’S Bodies, Linda Behar Jan 2014

Average (Arithmetic Mean) Of Women’S Bodies, Linda Behar

Electronic Theses and Dissertations 2010 - 2019

Between 1939 and 1940 the United States Government conducted a study of the measurements of women’s bodies to establish a standardized system of garment and pattern sizes. The central theme of my research is to analyze the female figure in the context of a technology-driven global contemporary society. My thesis exhibition includes a body of work that echoes the pressures that Western Society employs by standardizing women’s appearances. The focus of the work is to confront the viewer with a visual examination, which illustrates the preconceived notion that Western Society portrays the female body as a commodity and exports those …

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Bayesian Approach To An Exponential Hazard Regression Model With A Change Point, Yonas Kidane Abraha Jan 2014

Bayesian Approach To An Exponential Hazard Regression Model With A Change Point, Yonas Kidane Abraha

Electronic Theses and Dissertations 2010 - 2019

This thesis contains two parts. The first part derives the Bayesian estimator of the parameters in a piecewise exponential Cox proportional hazard regression model, with one unknown change point for a right censored survival data. The second part surveys the applications of change point problems to various types of data, such as long-term survival data, longitudinal data and time series data. Furthermore, the proposed method is then used to analyse a real survival data.

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Chief Nursing Officer Sustainment In The Continued Practice Of Nursing Leadership: A Phenomenological Inquiry, Angela S. Prestia Jan 2014

Chief Nursing Officer Sustainment In The Continued Practice Of Nursing Leadership: A Phenomenological Inquiry, Angela S. Prestia

Electronic Theses and Dissertations 2010 - 2019

The highly complex role of the Chief Nursing Officer (CNO) requires the refinement of a multitude of competencies and leadership skills in this unprecedented time of healthcare reform. As the senior most patient advocate in our medical centers the CNO is responsible for translating research into practice, policy development and implementation creating value based patient-centric strategies to transform health care. The ability to sustain and thrive in this role is essential in repositioning nursing as a knowledgeable discipline actively contributing to the redesign of healthcare. This exploratory descriptive phenomenological study was designed to explore and describe the elements that contribute …

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Understanding Behavioral Antitrust, Avishalom Tor Jan 2014

Understanding Behavioral Antitrust, Avishalom Tor

Journal Articles

Behavioral antitrust – the application to antitrust analysis of empirical evidence of robust behavioral deviations from strict rationality – is increasingly popular and hotly debated by legal scholars and the enforcement agencies alike. This Article shows, however, that both proponents and opponents of behavioral antitrust frequently and fundamentally misconstrue its methodology, treating concrete empirical phenomena as if they were broad hypothetical assumptions. Because of this fundamental methodological error, scholars often make three classes of mistakes in behavioral antitrust analyses: First, they fail to appreciate the variability and heterogeneity of behavioral phenomena; second, they disregard the concrete ways in which markets, …

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Critical Path Monitor Enabled Dynamic Voltage Scaling For Graceful Degradation In Sub-Threshold Designs, Yu Guang Chen, Tao Wang, Kuan Yu Lai, Wan Yu Wen, Yiyu Shi Jan 2014

Critical Path Monitor Enabled Dynamic Voltage Scaling For Graceful Degradation In Sub-Threshold Designs, Yu Guang Chen, Tao Wang, Kuan Yu Lai, Wan Yu Wen, Yiyu Shi

Electrical and Computer Engineering Faculty Research & Creative Works

Sub-threshold designs play an important role in energy constrained applications. In those designs, path delays depend exponentially on threshold voltage/temperature. As such, dynamic configurations at runtime are desired for best trade-off between operating power and performance. Unfortunately, most existing works only consider either process or temperature variations but not both, resulting in sub-optimal configurations or even functional failures. Moreover, little study has been performed on the graceful degradation of sub-threshold designs, which is important in the presence of drastic delay variations. Towards this, we present a novel critical path monitor based dynamic voltage scaling scheme. Considering both process and temperature …

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On The Deployment Of On-Chip Noise Sensors, Tao Wang, Chun Zhang, Jinjun Xiong, Yiyu Shi Jan 2014

On The Deployment Of On-Chip Noise Sensors, Tao Wang, Chun Zhang, Jinjun Xiong, Yiyu Shi

Electrical and Computer Engineering Faculty Research & Creative Works

Runtime noise management systems can enforce power integrity without significantly increasing design margins. These systems typically respond to on-chip noise sensors to accurately capture voltage emergencies. Unfortunately, it remains an open problem in the literature how to optimally place a given number of noise sensors for best voltage emergency detection, or how to best set the threshold voltage for these sensors. In this paper, we formally define the problem of noise sensor placement along with a novel sensing quality metric to be maximized. We then put forward an efficient algorithm to solve it, which is proven to attain the best …

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Calcite Dissolution Under Turbulent Flow Conditions: A Remaining Conundrum, Matthew D. Covington Jan 2014

Calcite Dissolution Under Turbulent Flow Conditions: A Remaining Conundrum, Matthew D. Covington

Geosciences Faculty Publications and Presentations

A significant body of experimental and theoretical work has examined the dissolution rates of calcite, and other carbonate minerals, under varying chemical and hydrodynamic conditions (see Morse & Arvidson (2002) for a comprehensive review). The relationships derived from this work have been applied extensively to the development of mechanistic models of speleogenesis (e.g. Dreybrodt 1996; Dreybrodt et al. 2005; Birk et al. 2005; Rehrl et al. 2008; Kaufmann 2009; Szymczak & Ladd 2011). However, the primary focus of these models has been on the early stages of cave formation, with less attention toward the later stages of cave evolution and …

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Reading Comprehension Assessment: A Comparison Of Academic And Clinical Measures, Emily Ann Stephens Jan 2014

Reading Comprehension Assessment: A Comparison Of Academic And Clinical Measures, Emily Ann Stephens

Theses and Dissertations

The Measures of Academic Progress (MAP) test is a computer-based academic assessment of reading comprehension that is used by school districts nationwide. The MAP has established reliability, but its validity is not widely available. The purpose of this study was to seek validity for the MAP by comparing it to the Gray Oral Reading Test--5th edition (GORT-5), a frequently used and valid clinical test of reading comprehension. Participants included twenty-eight fourth grade students ranging from 9;7 to 10;8 years of age, with a mean of 10;2. Each participant completed the GORT-5 and MAP test. The GORT-5 and MAP each yield …

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Study Of The Suit Inflation Effect On Crew Safety During Landing Using A Full-Pressure Iva Suit For New-Generation Reentry Space Vehicles, Suzuki Wataru Jan 2014

Study Of The Suit Inflation Effect On Crew Safety During Landing Using A Full-Pressure Iva Suit For New-Generation Reentry Space Vehicles, Suzuki Wataru

Theses and Dissertations

Recently, manned space capsules have been recognized as beneficial and reasonable human space vehicles again. The Dragon capsule already achieved several significant successes. The Orion capsule is going to be sent to a high-apogee orbit without crews for experimental purposes in September 2014. For such human-rated space capsules, the study of acceleration impacts against the human body during splashdown is essential to ensure the safety of crews. Moreover, it is also known that wearing a full pressure rescue suit significantly increases safety of a crew, compared to wearing a partial pressure suit. This is mainly because it enables the use …

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Translation Of Aadl To Pnml To Ensure The Utilization Of Petri Nets, Amrita Chatterjee Jan 2014

Translation Of Aadl To Pnml To Ensure The Utilization Of Petri Nets, Amrita Chatterjee

Theses and Dissertations

Architecture Analysis and Design Language (AADL), which is used to design and analyze software and hardware architectures of embedded and real-time systems, has proven to be a very efficient way of expressing the non-functional properties of safety-critical systems and architectural modeling. Petri nets are the graphical and mathematical modeling tools used to describe and study information processing systems characterized as concurrent and distributed. As AADL lacks the formal semantics needed to show the functional properties of such systems, the objective of this research was to extend AADL to enable other Petri nets to be incorporated into Petri Net Markup Language …

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Grade Level Retention: A Comparative Study Of Beliefs And Practices In North Dakota And Surrey, Kim Englund Jan 2014

Grade Level Retention: A Comparative Study Of Beliefs And Practices In North Dakota And Surrey, Kim Englund

Theses and Dissertations

Many regions of the United States retain students who are not performing at grade level, yet a large body of research shows the ineffectiveness of having students repeat an academic year. The United Kingdom practices social promotion rather than retention. This comparative study sought to better understand the practices in these two countries and the research surrounding retention. First, it compared the interventions before and alternatives to retention used by both a North Dakota school district in the United States and two schools in Surrey, England. Second, it outlined a plan for teachers, parents, school administrators, and school policy makers …

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