Digital Commons Network^™

Benthic Biological Monitoring Program Of The Elizabeth River Watershed (2007), Daniel M. Dauer

Elizabeth River Reports

Executive Summary

Macrobenthic communities of the Elizabeth River watershed have been quantitatively sampled since summer 1999. This report presents the data from the ninth year of sampling in 2007. The three objectives of the Benthic Biological Monitoring Program of the Elizabeth River watershed are: (1) To characterize the health of the tidal waters of the Elizabeth River watershed as indicated by the structure of the benthic communities. (2) To conduct trend analyses on long-term data at 14 fixed-point stations to relate temporal trends in the benthic communities to changes in water and/or sediment quality. Trend analyses will be updated annually …

Effects Of 5 Different Finger Rest Positions On Arm Muscle Activity During Scaling By Dental Hygiene Students, Mary E. Cosaboom-Fitzsimons, Susan Lynn Tolle, Michele L. Darby, Martha L. Walker

Dental Hygiene Faculty Publications

Purpose. This study was conducted to determine the effects of 5 different finger rest positions: opposite arch, standard intraoral, basic extraoral, cross arch, and finger on finger on the muscle activity of 4 forearm muscles (extensor carpi radialis longus, flexor carpi ulnaris, biceps brachii, and pronator teres) during a simulated periodontal scaling experience.

Methods. A convenience sample of 32 consenting senior dental hygiene students who met inclusion criteria participated. Using a 4 x 5 counter-balanced research design, each participant used a Gracey 11/12 curet to scale one cc of artificial calculus from first permanent molar typodont teeth (#3,14,19,30). Five different …

Integrating Preservation Functions Into The Web Server, Joan A. Smith

Computer Science Theses & Dissertations

Digital preservation of theWorldWideWeb poses unique challenges, different fromthe preservation issues facing professional Digital Libraries. The complete list of a website’s resources cannot be cited with confidence, and the descriptive metadata available for the resources is so minimal that it is sometimes insufficient for a browser to recognize. In short, the Web suffers from a counting problem and a representation problem. Refreshing the bits, migrating from an obsolete file format to a newer format, and other classic digital preservation problems also affect the Web. As digital collections devise solutions to these problems, the Web will also benefit. But the core …

Medical Image Modeling And Processing, Ramu Pedada

Electrical & Computer Engineering Theses & Dissertations

During the last few decades of the twentieth century, medical imaging has been playing a prominent role in many fields of biomedical research and clinical practice. Image modalities such as x-rays, computed tomography (CT), and magnetic resonance images (MRI) have all been valuable additions to the radiologist's arsenal of imaging tools. Medical images assure quality diagnosis and patient safety by gathering valuable information without invading the human body. Apart from clinical diagnosis, medical images are used as tools for education where they are used for training individuals before operating on a patient. Many medical educators tum to simulation based training …

Integer Ratio Logarithm Based Edge Detection For Runway Hazard Detection, Sri Satya Vardhan Gogineni

Electrical & Computer Engineering Theses & Dissertations

As air traffic is growing in leaps and bounds every day, flying safe has been a major concern in day to day life. Aviation safety is always dependent on the performance of the pilot and air traffic controllers. The very involvement of human discretion introduces judgment as a component of a safe takeoff and landing. A convenient and immediate alternative would be the use of technology to alleviate the problem. Several algorithms have been developed to solve this problem. However, most computer vision algorithms leave the task of interpreting the end data unaddressed. Juggling the myriad tasks during landing and …

Image Processing Technique For Runway Segmentation Using Color Spaces, Naresh Reddy Reddy

Electrical & Computer Engineering Theses & Dissertations

Aircrafts of the future now face the challenge of growing demand for safety which will require a more significant level of pilot assistance than is available today. During an approach to the airport runway, an algorithm that continuously segments the runway from the rest of the background with very little human intervention is very useful for both enhancing the landing safety and reducing the pilot's work load. This thesis presents a novel method for segmenting airport runways on a clear day and in poor visibility conditions using the color space components. In this thesis, collages were formed for both runway …

Detecting Portable Electronic Devices Onboard Commercial Aircraft, Randy Woods

Electrical & Computer Engineering Theses & Dissertations

The need to detect unauthorized usage of intentionally transmitting portable electronic devices (PEDs) onboard commercial aircraft is growing while still allowing passengers to use selected unintentionally transmitting devices, such as laptop computers and CD players, during non-critical stages of flight. This thesis presents the development and testing of an installed system for detecting PEDs over multiple frequency bands. Additionally, the advantages of a fixed versus mobile system are discussed.

Data is presented to cover the frequency range of 20 MHz to 6.5 GHz with special attention given to the cellular and PCS telephone bands, Bluetooth, and the family radio service …

Effect Of Outside Employment On Academic Success Among Full-Time Associate Degree Nursing Students, Julian A. Moore

Educational Leadership & Workforce Development Theses & Dissertations

Large portions of the United States are experiencing a shortage of nurses in the workplace. In 2001 the American Hospital Association reported that there were 126,000 vacancies for RNs nationwide. Sixty percent of all U.S. educated RNs who entered the field in 2000 received their education at the associate degree level and 79% of these associate degree recipients graduated from a community college. Improving completion rates in nursing programs is one major strategy in the effort to relieve this shortage of nurses.

The intent of this research was to study the effect of various factors on the academic achievement of …

Reflection High-Energy Electron Diffraction Studies Of Indium Phosphide (100) And Growth On Indium And Indium Nitride On Silicon (100), Mohamed Abd-Elsattar Hafez

Electrical & Computer Engineering Theses & Dissertations

Study of the effects of atomic hydrogen exposure on structure and morphology of semiconductor surfaces is important for fundamental properties and applications. In this dissertation, the electron yield of a hydrogen-cleaned indium phosphide (InP) surface was measured and correlated to the development of the surface morphology, which was monitored by in situ reflection high-energy electron diffraction (RHEED). Atomic hydrogen treatment produced a clean, well-ordered, and (2x4)-reconstructed InP(100) surface. The quantum efficiency, after activation to negative electron affinity, and the secondary electron emission were shown to increase with hydrogen cleaning time. RHEED patterns of low-index InP(100) surface were modified by the …

The Effect Of Intensity Of Aerobic Training On Insulin Sensitivity, Carmine Richard Grieco Iii

Human Movement Studies & Special Education Theses & Dissertations

Epidemiological studies have demonstrated that the prevalence of type 2 diabetes is increasing. It is estimated that I 0. 7% of adults over the age of 20 years and 23.1 % of adults over the age of 60 years have diabetes (NIH, 2007). Individuals with type 2 diabetes are 2-4 times more likely to die from heart disease than those without diabetes and twice as likely to die of all-cause mortality (CDC, 2005). Additionally Mokdad et al. (2000) report that the prevalence of diabetes increased 33% between 1990 and 1998. Furthermore it has been estimated that nearly 26% of the …

Failure Repair Model For A Device Using Minor And Major Maintenance Strategies, Hrishikesh Raman Phadke

Mechanical & Aerospace Engineering Theses & Dissertations

The major objective of this research was to study the maintenance decision process for systems with economic dependency. A probabilistic model was developed according to the proposed Markov model. After determining the maintenance cost through the markov models, we introduced the other costs associated with the device like operating cost and capital recovery cost, to get the total cost of all the activities involved in keeping the device. The optimal equivalent uniform cost can be found to occur at a particular number of life stages in the system. The nature of the equivalent uniform cost curve is dependent upon the …

Multivariable Flight Control Design Tool Incorporating Gain And Phase Root Locus, Yong Ki Yoon

Mechanical & Aerospace Engineering Theses & Dissertations

A challenging problem in flight control system design for highly maneuverable aircraft is the coordinated control of the lateral-directional axes. Design goals are based on desired flying qualities giving an indication of whether the response to pilot inputs will be acceptable. Satisfying these closed-loop design objectives employing a computerized flight control system requires multiple feedback and crossfeed paths which operate in a well coordinated fashion. Contemporary control design tools, which close all loops simultaneously, have addressed this problem for several decades. Concerns associated with these strategies are the complicated mathematical relationships between the designer inputs and resulting closed-loop properties, and …

Object Detection In Poor Visibility Conditions Using Image Segmentation, Triveni Vuppalapati

Electrical & Computer Engineering Theses & Dissertations

It can be dangerous for a pilot to attempt to land an aircraft safely in poor visibility conditions such as rain, fog, haze, snow and low light, but external imagery of a runway can be enhanced to provide increased situational awareness. Objects that are detected in a scene may or may not be a hazard, so interpretation is left to the pilot. In order to detect whether an object is a hazard to safe landing, it is necessary to determine whether the object is on the runway. For this purpose, two image segmentation algorithms: histogram based d-peak algorithm and local …

Experimental Analysis And Modeling Validation Of A Knee Brace In Shock Mitigation, Manish Prakash Dhekane

Mechanical & Aerospace Engineering Theses & Dissertations

An experimental setup simulating the dynamic environment in a high sea state is developed for the lower extremities to study the mitigation of shock impact. A single degree of freedom machine is equipped with six linear induction motors to produce impact acceleration ranging from 0.5G to 4G. The experiments are carried out along the dummy leg by using two configurations, one without a knee brace and one with a knee brace. Force and acceleration data is collected using a data acquisition system.

To develop the analytical model of the same experimental setup, the knee brace and dummy leg were scanned …

Performance Of Adaptive Wireless Systems With Feedback, Sirisha Koduri

Electrical & Computer Engineering Theses & Dissertations

Future generations of wireless systems will employ versatile transmitters and receivers based on software defined radios that are capable of adapting in response to changes in the operating environment to meet the specified quality of service requirements. In adaptive wireless systems, transmitters use feedback from the receiver to update characteristics of the transmitted signal to changing patterns of interference. In this thesis, the performance of transmitter adaptation algorithms with limited feedback and the system performance as a function in which the interference information is quantized for transmission over the feedback channel are analyzed. The results of this thesis were presented …

Image Pre-Processing Techniques For Hazard Detection In Poor Visibility Conditions, Girish Singh Rajput

Electrical & Computer Engineering Theses & Dissertations

Runway incursion is a persistent problem that has resulted in some of the most devastating accidents in aviation history. With ever increasing air traffic and more passengers, runway safety is of utmost priority to the Federal Aviation Administration (FAA) and other agencies concerned with aviation. As the issue of aviation safety becomes increasingly important, developing a consistent application that detects runway incursions in various visibility conditions is crucial for the aviation industry. This thesis presents a novel method for detecting runway hazards in poor visibility conditions using image processing techniques. The first step is to obtain images of a runway …

A Social Relational Model For Firm-Hosted Virtual Communities: The Role Of Firm Support, Tung Duy Cu

Theses and Dissertations in Business Administration

Since the ease of participation and the usefulness of information provided by online groups continue to proliferate in the World Wide Web, people increasingly participate in different forms of virtual community (i.e. online forums, bulletin boards, message boards, chat rooms) for their purposes, such as solving problems, building social relationships, sharing passions, developing professionals.

Accordingly, an increasing number of companies are now attempting to exploit this phenomenon by hosting and supporting their own online community for commercial and non-commercial purposes, such as building relationships with their customers, getting their feedback, strengthening the brand, and reducing customer service costs by enabling …

Nonlinear Flutter Analysis Of Curved Panels Under Yawed Supersonic Flow And At Elevated Temperatures Using Finite Elements, Satyajit Sudhir Ghoman

Mechanical & Aerospace Engineering Theses & Dissertations

There are large number of papers dedicated toward the investigation of flutter analysis of flat plates in supersonic flow regime, but very few papers address the problem of flutter of curved panels. Furthermore, many of the panel flutter investigations including thermal effects, have dealt with liat plates. Scarce literature exists regarding the flutter of curved panels with thermal effects. Hence, the objective of this thesis is to develop, for the first time in the literature, a consistent finite element formulation and an efficient solution procedure to investigate nonlinear flutter of curved panels at yawed supersonic flow at elevated temperatures.

Panel …

Extending The Network Life Time In Wsn Using Energy Efficient Algorithm, Venkata Sesha Sai Koundinya Goparaju

Electrical & Computer Engineering Theses & Dissertations

Wireless Sensor networks have many potential applications. These wireless sensor networks necessitate specific design requirements of which energy efficiency is vital. The sensor networks consist of sensor nodes that operate on battery power, and replacement of these batteries is very often a strenuous task, since networks are deployed in areas where the act of replacing the batteries proves impractical.

With the limited available energy of sensor nodes, most of the energy is drained during communication. An energy efficient routing algorithm can prolong the lifetime of the network by gradually depleting the nodes in the network. Many of the routing protocols …

Joint Transform Correlation With A Synthetic Discrimination Function For Object Classification, Inder K. Purohit

Electrical & Computer Engineering Theses & Dissertations

A novel method using adaptive progressive thresholding (APT) and shifted phase-encoded fringe-adjusted joint transform correlation (SPFJTC) that employs a synthetic discriminant function (SDF) image for object classification is presented in this thesis. An adaptive progressive thresholding scheme first processes the given input scene to separate any objects present in the scene from the background. The preprocessing step results in an image having only the foreground objects, such as boats, trees and other cluttered regions, and hence reduces the search space for the correlation step significantly. The processed irμage is then fed to the shifted phase-encoded fringe-adjusted joint transform correlator, which …

The Nature Of K-12 Teacher Need Through 2050: A Demographic Investigation Of The Teacher Shortage Crisis In The United States, Rebecca M. Mullen

Sociology & Criminal Justice Theses & Dissertations

In this paper, I outlined research regarding a so-called "crisis" in K-12 education in the United States, which refers to an alleged shortage of teachers that is manifesting and will continue to manifest itself in the near future. I then used a modified version of the cohort component analysis to project the number of teachers needed to project the number of a) students who will be enrolled in public or private K-12 education in the united states, b) teachers needed to maintain the student to teacher ratio in the United States as of the year 2000, 16.0, by benchmark year …

Using Agile Software Development Practices In A Research Oriented Distributed Simulation, Douglas James Mielke

Computational Modeling & Simulation Engineering Theses & Dissertations

Although sometimes controversial, agile methodologies have proven to be a viable choice for some software development projects. Projects suited to agile methodologies are those that involve new technology, have requirements that change rapidly, and are controlled by small, talented teams. Much literature about agile software development leans towards business products and non-government entities. Only a handful of literature resources mention agile software development being used in government contracts and even fewer resources mention research projects. NASA's Airspace and Traffic Operations Simulation (ATOS) is a research oriented simulation that doesn't follow the traditional business project mold. In an effort to gain …

Robust Edge-Detection Algorithm For Runway Edge Detection, Swathi Tandra

Electrical & Computer Engineering Theses & Dissertations

Fog and other such weather conditions hamper the visibility of runway surfaces and any obstacles present on the runway, creating a situation where a pilot may not be able to safely land the aircraft. Assisting the pilot to land the aircraft safely in such conditions is an active area of research. A new method is being investigated that combines non-linear image enhancement with classification of runway edges to detect objects on the runway. The image is segmented into runway and non-runway regions, and objects that are found in the runway regions are deemed to constitute potential hazards. For runway edge …

The Line In The Sand: Understanding Customer Sexual Harassment Through A Psychological Contract Framework, Valerie J. Morganson

Psychology Theses & Dissertations

Research has demonstrated that customer sexual harassment (CSH) is a frequently occurring phenomenon and an apparent barrier to the career development of women (Gettman & Gelfand, 2007; Morganson & Major, 2008). The current study applies psychological contract theory toward understanding how CSH leads to adverse outcomes, which affect individuals and organizations. A sample of 420 working women including both students and full-time non-student workers from various organizations were recruited to participate in this online study. CSH and perceptions of employer obligation did not interact to predict psychological contract breach. As hypothesized, psychological contract breach and CSH interacted to predict affective …

Microtextures Of Cyanobacterial Mats In Siliciclastic Sedimentary Environments (Modern & Ancient): Applications To The Search For Life On Mars, Dina M. Bower

OES Theses and Dissertations

The current Mars Exploration Rover Program (MER) is one of NASA's most successful missions. The aim of the MER is to explore for possible life on the surface of Mars. My thesis developed new methods of how to detect and to identify microbial mats in siliciclastic sediments (modern and ancient), and to make recommendations on the applicability of MISS as biosignatures. Predominantly, I employed instrumentation portable by future rovers. To search for life on other planets, we need to have information on how this life might look. Most astrobiological studies therefore focus on Earthly analogues of life and its habitats. …

Biology-Inspired Approach For Communal Behavior In Massively Deployed Sensor Networks, Kennie H. Jones

Computer Science Theses & Dissertations

Research in wireless sensor networks has accelerated rapidly in recent years. The promise of ubiquitous control of the physical environment opens the way for new applications that will redefine the way we live and work. Due to the small size and low cost of sensor devices, visionaries promise smart systems enabled by deployment of massive numbers of sensors working in concert. To date, most of the research effort has concentrated on forming ad hoc networks under centralized control, which is not scalable to massive deployments. This thesis proposes an alternative approach based on models inspired by biological systems and reports …

Investigation Of (E, 2e) Collisions And Related Phenomena, Jason Manuel Martinez

Physics Theses & Dissertations

In this thesis I investigate (e, 2e) processes, or electron impact ionization, using several theoretical methods. I first examine the problem using the Born approximations, particularly the Distorted Wave Born Approximation (DWBA), focusing on the underlying processes that dominate for ionization of the 2p state of Argon and Magnesium. I investigate as well the ionization of helium and hydrogen and use the simplicity of the approximation to probe the incident particle effects on the Helium cross section. In both cases the results are compared with experiment. I also produce cross section results for ions near threshold, a regime that …

Congestion Mitigation In Wireless Sensor Networks Using Single-Hop Backpressure Algorithm, Vijay Shekar Mangilipalli Gangu Sham

Electrical & Computer Engineering Theses & Dissertations

Wireless sensor networks consist of a group of small components with limited resources allocated to sense the environment and transmit data to the user or interpreter. This concept is technically evolved from Sensors that are basically used to sense the environment around and collect data based on the sensing application incorporated in them. An extension to functionality of the sensors leads to the concept of sensor networks, where, in addition to gathering information at individual sensors, the data is processed and transmitted to a central station or Base station. This concept of transmitting the information from one node to the …

Investigation Of Loading Of Pulsed And Continuous-Wave Optical Dipole Force Traps, M. Shiddiq, E. M. Ahmed, M. D. Havey, C. I. Sukenik

Physics Faculty Publications

We have investigated the behavior of an optical dipole force trap realized using a mode-locked Nd:YAG laser and have compared performance to a continuous-wave (cw) trap built using the same laser but running in a cw mode. The traps are used to confine ultracold 85Rb atoms which are loaded from a magneto-optical trap (MOT). In most respects, the two traps behave similarly over a wide range of laser parameters provided that the average potential well depth is the same; however, there is a notable difference in the dipole trap loading efficiency dependence on the detuning of the MOT trap laser …

Extended Tuning Of An Injection-Locked Diode Laser, M. K. Shaffer, G. Ranjit, C. I. Sukenik

Physics Faculty Publications

We have investigated the application of an electronic feedback technique recently reported by Repasky, et.al. [Appl. Opt. 45, 9013 (2006)] to an injection-locked semiconductor diode laser. We find that without electronic feedback, the injection-locked slave laser will only follow the master for less than 1 GHz, but once the electronic feedback is applied, the slave laser is capable of following for more than 20 GHz, corresponding to the full scan range of the master laser.