Digital Commons Network^™

Supporting Data-Intensive Wireless Sensor Applications Using Smart Data Fragmentation And Buffer Management, Mbonisi Masilela

Theses and Dissertations

Recent advances in low power device technology have led to the development of smaller powerful sensors geared for use in Wireless Sensor Networks. Some of these sensors are capable of producing large data packets in a single reading. This becomes a challenging problem given the constraints imposed by current MAC and Transport Layer implementations since a single data packet can exceed the MTU of the protocol stack. Little has been done in the way of addressing this issue in Wireless Sensor Networks. This paper proposes a novel solution to this issue. Proposed is a Lightweight Data Transportation Protocol that uses …

On Optimal Survivability Design In Wdm Optical Networks Under Scheduled Traffic Models, Tianjian Li

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Wavelength division multiplexing (WDM) optical networks are widely viewed as the most appropriate choice for future Internet backbone with the potential to fulfill the ever-growing demands for bandwidth. WDM divides the enormous bandwidth of an optical fiber into many non-overlapping wavelength channels, each of which may operate at the rate of 10 Gigabit per second or higher. A failure in a network such as a cable cut may result in a tremendous loss of data. Therefore, survivability is a very important issue in WDM optical networks. The objective of this dissertation is to address the survivability provisioning problem in WDM …

An Initial Methodology For The Definition And Implementation Of Unmanned Aerial Vehicle Agent Behaviors, William Eric Marsh

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In many current agent-based modeling systems, it is difficult for a domain-expert user to define and implement agent behaviors without possessing extensive programming knowledge. MUAVES is an existing simulation environment that serves as a research testbed for examining command and control issues with unmanned aerial vehicle (UAV) systems containing many vehicle agents. In its previous form, defining agent behaviors required knowledge of the C# programming language that some MUAVES users did not have. This thesis presents a new methodology for the definition and implementation of UAV agent behaviors in MUAVES. The new methodology is based on diagramming an agent's controller …

Designing Computer Agents With Personality To Improve Human-Machine Collaboration In Complex Systems, Sasanka V. Prabhala

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The dynamic nature of complex systems and the overwhelming amount of data that must be handled by human operators requires the development of smart systems that augment human capabilities. For these systems human-agent collaboration is part of the system dynamic. Unfortunately the computer agent is not typically perceived by the human operator as a collaborative team member. This research addressed the key question of how to develop and evaluate computer agents with personality to enhance human-machine collaboration. To move towards this goal three research objectives were established: (1) develop agents with personality, (2) validate that humans perceive these agents as …

Transformation Of Formally Defined Post-Conditions Into Target Language Statements, Swetha Padma Parvathaneni

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For years software engineering researchers have been trying to come up with a software synthesis system that can transform a formal specification model into a design model from which executable code can be generated. AFIT Wide Spectrum Object Modeling Environment (AWSOME) is one such formal based software synthesis system. In this system formal specifications written in AWL are parsed into an AST (Abstract Syntax Tree). The intent of this thesis is to demonstrate the transformation of the postconditions of a method into target language statements. The methods in the classes are specified using pre-conditions and post-conditions. Transforms are developed to …

A Gnu Radio Based Software-Defined Radar, Lee K. Patton

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GNU Radio is an open source software-defined radio project, and the Universal Software Radio Peripheral (USRP) is hardware designed specifically for use with GNU Radio. Together, these two technologies have been used to implement very sophisticated, yet low cost, software-defined radios. Since software-defined radio and software-defined radar are really one in the same technologies, it stands to reason that GNU Radio and the USRP could be utilized to form a low cost radar sensor. In this thesis, we discuss the design of a prototype software-defined radar, built using the open source GNU Radio and open specification USRP projects. The prototype …

Role-Based Access Control For The Open Grid Services Architecture - Data Access And Integration (Ogsa-Dai), Anil L. Pereira

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Grid has emerged recently as an integration infrastructure for the sharing and coordinated use of diverse resources in dynamic, distributed virtual organizations (VOs). A Data Grid is an architecture for the access, exchange, and sharing of data in the Grid environment. In this dissertation, role-based access control (RBAC) systems for heterogeneous data resources in Data Grid systems are proposed. The Open Grid Services Architecture - Data Access and Integration (OGSA-DAI) is a widely used framework for the integration of heterogeneous data resources in Grid systems.

However, in the OGSA-DAI system, access control causes substantial administration overhead for resource providers in …

Low African-American Student Enrollment In The Post Secondary Vocational Education Step Ii Program: A Study Of Motivational Factors, Victor Goldstein

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A purposive literature review was used in this study to develop a knowledge base on motivational factors impacting enrollment of African-American students in postsecondary vocational education program specifically in the STEP II program. This study examined books, articles, reports, and data from student interviews to understand what motivational factors influence decisions. It was found that low enrollment of African- American students in post-secondary vocational education is not only dependent on motivational factors emanating from the students themselves, but also stem from the institutions that offer training programs.

Algan/Gan Hemt Topology Investigation Using Measured Data And Device Modeling, Derrick Langley

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Investigation has been done on procedure, development, and verification of transistor topology for Aluminum-Gallium Nitride/Gallium Nitride (AlGaN/GaN) High-Electron Mobility Transistor (HEMTs). To date various models have been published that address modeling issues dealing with AlGaN/GaN HEMTs. Many models rely on analytic parameter solutions to help define model behavior. In order to find an optimum transistor at X-band frequency, 8-12 Gigahertz (GHz), layout, testing, modeling and simulation was conducted on various transistor topologies. Theoretical and experimental analysis has been completed for device operating point selection in measurement and modeling to account for self-heating and radio frequency (RF) dispersion effects. The model …

Xml Integrated Environment For Service-Oriented Data Management, Marwan Younes Maarouf

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The proliferation of XML as a family of related standards including a markup language (XML), formatting semantics (XSL style sheets), a linking syntax (XLINK), and appropriate data schema standards have emerged as a de facto standard for encoding and sharing data between various applications. XML is designed to be simple, easily parsed and self-describing. XML is based on and support the idea of separation of concerns: information content is separated from information rendering, and relationships between data elements are provided via simple nesting and references. As the XML content grows, the ability to handle schemaless XML documents becomes more critical …

Black Hole: The Role Of Black Aesthetics In Science Fiction, Thomas Leo Johnson

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The main purpose of this thesis is to answer the question of why the genre of science fiction permits African-American authors to expand their themes beyond African-American concerns and characters. This thesis puts forward the argument that science fiction provides African-American writers with the capacity to craft their works' central conflicts to include or exclude issues that affect the Black community. This thesis answers the question in four points, the first being a brief historical overview of the debate within the Black literary community on the prevalence of Black aesthetics. The overview also gives a summary of the debate over …

Core Content Teachers' Prepardeness And Perception Of Inclusive Education In Central Ohio Schools, Christine Ann Crumbacher

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The purpose of this study was to survey core content teachers' (CCTs) perceptions of working with children with disabilities in the subject areas of English, math, science and social studies in two school districts (referred to as school district 1 and 2). The survey consisted of 3 subscales: internal, external and social and were formatted in a Likert-type scale. The research questions in this study are: 1.) Do CCTs feel prepared to teach students with disabilities across districts and buildings based on the internal subscale? 2.) Do schools prepare CCTs to teach students with disabilities across districts and buildings based …

Effect Of Variable Feedback Delay On Visual Target-Acquisition Performance, Julio Christian Mateo

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Traditionally, private communication channels with stable characteristics have been used in teleoperation situations. However, recently there have been a few attempts at using public communication channels such as the Internet. In spite of their convenience, very little is known about the effect of the variable delays inherent in this type of channel on motor performance. In this thesis, we provide empirical data on the impact of variable feedback delays on a 3D visual target-acquisition task performed in a virtual environment. Target size, distance between targets, mean feedback delay, and feedback-delay variability were manipulated and the number of errors and movement …

The False Promise Of International Financial Institutions In Building Stable Democracies In Third World Countries, Foday Sulimani

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The available literature on the democratic process in third world countries shows that there is a strong correlation between the strength of a country's economic and social infrastructure and the successful promotion of democratic principles. It is my assumption that democracy can not be established without strong economic and social infrastructures. Furthermore, the current aid programs as operated by international financial institutions (IFIs) like the International Monetary Fund (IMF), the World Bank and the United States Agency for International Development (USAID) give false hope to third world countries that fail to develop sound socioeconomic policies and yet want to establish …

Investigation Of Cylindrically-Conformed Four-Arm Spiral Antennas, Douglas J. Glass

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A four-arm spiral antenna offers broadband frequency response, wide beamwidths, reduced size compared to other antenna designs, and the ability to determine the relative direction of an incident signal with appropriate mode-forming. The reduced overall area projection of the four-arm spiral antenna compared to other antenna designs and the ability to be manufactured in a planar format allows the antenna to reside within an Unmanned Air Vehicle (UAV) fuselage. This thesis investigates the effects of cylindrically-conforming two different designs of a four-arm spiral antenna to reside within the fuselage of a medium-sized UAV. Theoretical predictions of antenna performance were created …

Parameterizable Channelized Wideband Digital Receiver For High Update Rate, Peter E. Buxa

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Wideband digital receivers are important components used prevalently by the United States Air Force for many modern electronic warfare systems. Currently, many digital receiver architectures are designed for a specific mission requirement and are not parameterizable, modular, or reusable for varying mission requirements. Also, many designs are technology, platform, and vendor dependent which make upgrading existing fielded systems costly and difficult. Additionally, current wideband FFT-based digital receivers must wait until a number of samples equal to the size of the FFT are collected before spectral information can be updated. Achieving a high spectral update rate is important for the accurate …

Design And Performance Evaluation Of 1 Giga Hertz Wideband Digital Receiver, Kiranraj George

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The lack of a priori knowledge about the waveform of interest, the multitudes of signals the receiver might receive, and the noise energy that occupies the same portion of the frequency spectrum as the signal makes the design of a modern wideband receiver very challenging. Especially, the receiver must be able to detect a weak signal in the presence of a strong one, which requires a high two-signal instantaneous dynamic range (IDR). To fulfill this requirement, the receiver must detect genuine weak signals and avoid the detection of strong signals' sidelobes and noise and spurs generated from the receiver system. …

The Value Of Deliberative Democratic Practices To Civic Education, Brooke M. Shannon

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The causal relationship between measures of deliberative democratic practices and quality of citizen participation were examined using selected variables from the International Association for the Evaluation of Education Achievement's (IEA) 1999 Civic Education Study (CivEd). Logit regression for survey data was used to analyze whether a causal relationship existed between two indicators of deliberative democratic practices and a total of four measures of both current and expected student participation using data from three countries, the United States, England, and Australia. One independent variable, the degree to which students believed their teachers encouraged discussion of controversial political or social issues, had …

Minute Doping Of Pulsed Laser Deposition Processed Y123 Thin Films With Tb, Ce, And Pr, Joseph William Kell

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Three rare earth elements (Tb, Ce, and Pr) were chosen for the investigation into whether adding minute quantities (≤1 at%) of dopants could improve the film quality of YBa₂C ₃O_7-δ(Y123) thin films. The compositions studied are (Y_1-x,Re_x)Ba₂Cu₃O_7-δ (RE=Tb, Ce, Pr; x=0.1, 0.01, 0.001). Good quality thin films were produced by PLD and showed significant improvement to properties when exposed to a magnetic field. Ce and Pr (x=0.001) doped films showed modest improvement. However, the Tb doped system showed substantial improvement to J_c(H), with a …

Moving On: A Novel, Brian P. Leingang

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Hank Fossett had the perfect life with his girlfriend, Liz: a steady job, a promising career as a local artist, a healthy relationship with a wonderful woman, all while living in the cosmopolitan city of Blophton. But Hank was just dumped and didn't see it coming. Now, after four years with his girlfriend, he's alone and must figure out how to get over the girl who broke his heart. Turns to his friends to help him try to get Liz back. Instead, they help Hank get over Liz in a series of twelve steps crafted by Hank's old friend and …

Distribution Of Ground-Layer Plant Species In A Fragmented Landscape In The Corozal District, Belize, Central America, Divan Catzim

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In this study, I specifically looked at three major issues regarding 36 target plant species in a fragmented landscape in the Corozal district, Belize: 1) Determine woodlot characteristics that tend to favor the target species. 2) Determine plant characteristics that tend to favor the target species. 3) Determine whether age and size of a woodlot favors the presence of the target species. The study area was divided into three areas and each area had woodlots varying in sizes and ages. 36 plant species were sampled in all woodlots upon which woodlot characteristics and species characteristics were associated with the number …

Investigation Of Interactions Between Rev And Microtubules: Purification Of Wild-Type And Mutant Rev Protein And Optimization Of Microtubule Depolymerization Assays, Miller, Kelly Robbins

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As a logical pharmaceutical target for antiviral drugs, HIV-1 Rev is a regulatory protein essential for viral infection (Hope, 1999). The development of antiviral drugs that target Rev has been hindered by the lack of high-resolution structural information due to the protein's tendency to aggregate in solution. While searching for solution conditions rendering Rev amenable to crystallographic analyses, Watts et al., (2000) discovered a novel in vitro interaction between Rev and microtubules (MTs) whereby addition of equimolar Rev and tubulin forms bilayered rings called Rev-tubulin toroidal complexes (RTTs). RTTs are similar to those seen when MTs are mixed with certain …

Analysis Of Sex Reversal And Tra-2 Nucleotide Variation In Tropical And Temperate Clades Of Caenorhabditis Briggsae, Irene Zelepuhin

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Reproductive isolation results when members of the same species cannot reproduce due to either prezygotic or postzygotic mechanisms, therefore restricting gene flow between populations. A leading model describing reproductive isolation developed by J.B. Haldane (1922) states, "When offspring from two different animal species have one sex that is rare, absent, or sterile, that sex is the heterozygous (XO) or heterogametic (XY) sex". Haldane's rule is illustrated among various animal taxa regardless of which sex is heterogametic. To date, Caenorhabditis mating tests are the only example of Haldane's rule that is caused by sexual transformation and not gender specific lethality or …

The Demise Of Industrial Education For African Americans: | |Revisiting The Industrial Curriculum In Higher Education, William L. Allen

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The purpose of this study was to examine the causes that led African Americans to resist industrial education higher education, which ended industrial training programs in predominantly Black colleges and universities during the 1920s.

Three key factors helped create this reform movement: 1) the death of Booker T. Washington; 2) the improved educational levels of African Americans; and 3) the rise in aspirations of African Americans to expand the benefits of higher education. The loss of the Civil War caused a reorientation of southern and economic conditions.

Newly freed slaves had to be granted citizenship. Southern Whites were more concerned …

Impact Of Land Use On Water Quality In The Indian Lake Watershed: An Integrated Geographic Information Systems Approach, Michael Belke

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Geology and land use and land cover are the most important factors that influence water quality. The purpose of this study is to investigate how these factors operate in a rural watershed. Specifically, this thesis tests the feasibility of a proposed formula to relate how land use affects surface water quality and to infer hydrogeochemical reactions that control water chemistry through hydrogeochemical speciation and mineral stability relationships. Samples were collected from Indian Lake and its watershed in West-Central Ohio. BASINS, produced by the USEPA, was then used to delineate sub-watersheds and find the land use areas of these watersheds. The …

Cross-Cultural Differences Between Korean And American College Students' Perceptions Of Sexual Harassment In Conversational Appropriateness, Yunekyong Chae

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The purpose of this study was to compare the cross-cultural differences of Korean and American college students' perceptions of their experiences with sexual harassment and how it impacts their thoughts and feelings. This study extends the sexual harassment literature to include Koreans' experiences with this important topic. Therefore, this study addresses four research questions: RQ1: Are there cultural differences between Korean and American students' perceptions of sexual harassment in conversational appropriateness? RQ2: Are there gender differences between Korean and American students' perceptions of sexual harassment in conversational appropriateness? RQ3: Will American students report perceptions of sexually harassing conversations more frequently …

Characteristics Of A Foamy Virus-Derived Vector That Allow For Safe Autologous Gene Therapy To Correct Leukocyte Adhesion Deficiency Type 1, Ryan Matthew Mcnichol

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The hematopoeitic stem cell is a prime target for gene therapy in the attempt to correct a number of single gene inherited genetic defects that affect the immune system. In persons affected by leukocyte adhesion deficiency type 1 (LAD-1) the gene for the Beta-2 subunit of the integrin molecule is mutated. This autosomal recessive gene defect yields a phenotype with little or no beta-2 integrin expression on leukocytes. Beta-2 integrin expression is essential for leukocytes to travel from the blood to the tissues to fight infection. Persons with this disease have lowered leukocyte counts in the tissues and as a …

Hsv-1 Infection Of C3h Central Nervous System Cell Lines, Lauren Kay Van Buren

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Herpes Simplex Virus Type 1 (HSV-1) can infect the nervous system, resulting in a disease known as herpes encephalitis (HSE). Herpes encephalitis affects thousands of people each year; many cases are fatal or permanently debilitating. Approximately two thousand known cases occur in the United States each year alone (Neuroland online source). Acyclovir has been the drug of choice used to treat herpes encephalitis. Even after the administration of acyclovir, permanent neurological damage and/or death often results. Thousands of individuals would benefit by the discovery of drugs that are more effective at preventing lasting HSE damage and death. Knowledge concerning HSE …

Fpga Based Hardware Implementation Of Advanced Encryption Standard, Sowrirajan Sampath

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On October, 2, 2000, The National Institute of Standards and Technology (NIST) announced Rijndael as the new Advanced Encryption Standard (AES). The other competing algorithms were Mars, RC6, Serpent and Two-fish. The Predecessor to the AES was Data Encryption Standard (DES) which is considered to be insecure because of its vulnerability to brute force attacks. DES was a standard from 1977 and stayed until the mid 1990's. However, by the mid 1990s, it was clear that the DES's 56-bit key was no longer big enough to prevent attacks mounted on contemporary computers, which were thousands of times more powerful than …

The Effects Of Representational Format And Discourse Principles On The Comprehension And Production Of Temporal Order, Louise J. Rasmussen

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In the present study I examined the role physical representations play in supporting distributed planning and scheduling. Specifically, I investigated the implications of different representational formats for the production of discourse as well as the later comprehension of text relating to temporal order. In the first part of the study, pairs of participants created schedules for constructing a house with the aid of either a numeric, list format, or a graphical, Gantt chart format. Participants completed the task in a non-collocated fashion, without shared visual access. In the second part of the study, after completing their schedule, the same participants …