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Service Oriented Networking For Multimedia Applications In Broadband Wireless Networks, Ehsan Haghani Dogaheh Jan 2010

Service Oriented Networking For Multimedia Applications In Broadband Wireless Networks, Ehsan Haghani Dogaheh

Dissertations

Extensive efforts have been focused on deploying broadband wireless networks. Providing mobile users with high speed network connectivity will let them run various multimedia applications on their wireless devices. In order to successfully deploy and operate broadband wireless networks, it is crucial to design efficient methods for supporting various services and applications in broadband wireless networks. Moreover, the existing "access-oriented" networking solutions are not able to fully address all the issues of supporting various applications with different quality of service requirements. Thus, "service-oriented" networking has been recently proposed and has gained much attention.

This dissertation discusses the challenges and possible …


Safe Haven Infant Protection : Incidence Of Use And Characteristics Of Surrendered Infants And Relinquishing Users, Sallie Anne Porter Jan 2010

Safe Haven Infant Protection : Incidence Of Use And Characteristics Of Surrendered Infants And Relinquishing Users, Sallie Anne Porter

Dissertations

Background: Safe Haven Infant Protection (SHIP) laws are variously-titled state-level laws that permit infants to be surrendered to designated persons and/or places in a generally anonymous fashion with prescribed limits on prosecution.

Objective: The objective of this study was to determine the number of infants surrendered under SHIP laws in the United States, detail the characteristics of surrendered Safe Haven (SH) infants and relinquishing users, and directly compare the SH infant/relinquishing user population and the discarded infant/discarding mother populations.

Methods: Non-profit reports and communications, government documents and communications, and media reports provided the basis of the national SH estimate. Data …


Optimal Train Control On Various Track Alignments Considering Speed And Schedule Adherence Constraints, Kitae Kim Jan 2010

Optimal Train Control On Various Track Alignments Considering Speed And Schedule Adherence Constraints, Kitae Kim

Dissertations

The methodology discussed in this dissertation contributes to the field of transit operational control to reduce energy consumption. Due to the recent increase in gasoline cost, a significant number of travelers are shifting from highway modes to public transit, which also induces higher transit energy consumption expenses.

This study presents an approach to optimize train motion regimes for various track alignments, which minimizes total energy consumption subject to allowable travel time, maximum operating speed, and maximum acceleration/deceleration rates. The research problem is structured into four cases which consist of the combinations of track alignments (e.g., single vertical alignment and mixed …


Resource Assignment In Short Life Technology Intensive (Slti) New Product Development (Npd), Randy A. Reagan Jan 2010

Resource Assignment In Short Life Technology Intensive (Slti) New Product Development (Npd), Randy A. Reagan

Dissertations

Enterprises managing multiple concurrent New Product Development (NPD) projects face significant challenges assigning staff to projects in order to achieve launch schedules that maximize financial returns. The challenge is increased with the class of Short Life Technology Intensive (SLTI) products characterized by technical complexity, short development cycles and short revenue life cycles. Technical complexity drives the need to assign staffing resources of various technical disciplines and skill levels. SLTI products are rapidly developed and launched into stationary market windows where the revenue life cycle is short and decreasing with any time-to-market delay. The SLTI-NPD project management decision is to assign …


Inter-Relationship Of Mechanical And Bio-Chemical Processes Governing The Settlement Of Municipal Solid Waste (Msw) Using The (C +H)/L Ratio, Joseph John Lifrieri Jan 2010

Inter-Relationship Of Mechanical And Bio-Chemical Processes Governing The Settlement Of Municipal Solid Waste (Msw) Using The (C +H)/L Ratio, Joseph John Lifrieri

Dissertations

This research discusses the results of experimentation that determines the rates and magnitudes of consolidation and settlement of solid waste materials dependent upon their actual state of biodegradation decomposition and time in place. The state of decomposition of waste is determined by measuring its cellulose plus hemicellulose to lignin ratio ((C + H)/L). The samples were collected from bioreactors, at consecutive time intervals, to simulate states of decomposition.

Each sample was tested in consolidation to determine the value of the primary compression index C' c, the secondary compression index "the inorganic creep rate" coefficient, C' α, and the …


End-Of-Life Analysis Of Nanotechnology Products, Sun Olapiriyakul Jan 2010

End-Of-Life Analysis Of Nanotechnology Products, Sun Olapiriyakul

Dissertations

Previous research has shown that thermodynamic properties including melting point and specific heat capacity of nanomaterials may be higher than that of their corresponding bulk materials. The melting point elevation and specific heat capacity enhancement of nanomaterials may result in increased energy consumption and waste gases emission at the end-of-life (EOL) stage where the products containing nanomaterials are recycled by high temperature metal recovery (HTMR) process.

In this dissertation, the effect of physical characteristics of nanomaterials, referred to as physicochemical parameters, on their melting temperature and specific heat capacity was investigated. In addition, physical, chemical, and thermodynamic properties of nanomaterials …


Integration Of Electronic And Optical Techniques In The Design And Fabrication Of Pressure Sensors, Ivan Padron Jan 2010

Integration Of Electronic And Optical Techniques In The Design And Fabrication Of Pressure Sensors, Ivan Padron

Dissertations

Since the introduction of micro-electro-mechanical systems fabrication methods, piezoresistive pressure sensors have become the more popular pressure transducers. They dominate pressure sensor commercialization due to their high performance, stability and repeatability. However, increasing demand for harsh environment sensing devices has made sensors based on Fabry-Perot interferometry the more promising optical pressure sensors due to their high degree of sensitivity, small size, high temperature performance, versatility, and improved immunity to environmental noise and interference. The work presented in this dissertation comprises the design, fabrication, and testing of sensors that fuse these two pressure sensing technologies into one integrated unit. A key …


Nonlinear Evolution Of Annular Layers And Liquid Threads In Electric Fields, Qiming Wang Jan 2010

Nonlinear Evolution Of Annular Layers And Liquid Threads In Electric Fields, Qiming Wang

Dissertations

The nonlinear dynamics of viscous perfectly conducting liquid jets or threads under the action of a radial electric field are studied theoretically and numerically here. The field is generated by a potential difference between the jet surface and a concentrically placed electrode of given radius. A long-wave nonlinear model that is used to predict the dynamics of the system and in particular to address the effect of the radial electric field on jet breakup is developed, Two canonical regimes are identified that depend on the size of the gap between the outer electrode and the unperturbed jet surface. For relatively …


Relationship Between Photospheric Magnetic Fields And Coronal Activities, Changyi Tan Jan 2010

Relationship Between Photospheric Magnetic Fields And Coronal Activities, Changyi Tan

Dissertations

Coronal emission comes in two forms, a steady component where the corona is heated to million degrees and a much hotter transient component of solar flares. Both components are known to be related to the evolution of surface magnetic fields. This dissertation studies the evolution of photospheric magnetic fields and flow fields and their relation to the properties of these two coronal emission components.

The key issue in the study of the steady coronal emission is the coronal heating problem: how the corona is heated to millions of degrees while the underlying solar photosphere is only a few thousand degrees. …


Cooperative Retransmission Protocols In Fading Channels : Issues, Solutions And Applications, Igor Stanojev Jan 2010

Cooperative Retransmission Protocols In Fading Channels : Issues, Solutions And Applications, Igor Stanojev

Dissertations

Future wireless systems are expected to extensively rely on cooperation between terminals, mimicking MIMO scenarios when terminal dimensions limit implementation of multiple antenna technology. On this line, cooperative retransmission protocols are considered as particularly promising technology due to their opportunistic and flexible exploitation of both spatial and time diversity. In this dissertation, some of the major issues that hinder the practical implementation of this technology are identified and pertaining solutions are proposed and analyzed. Potentials of cooperative and cooperative retransmission protocols for a practical implementation of dynamic spectrum access paradigm are also recognized and investigated. Detailed contributions follow.

While conventionally …


Job Seeking And Job Application In Social Networking Sites : Predicting Job Seekers' Behavioral Intentions, Maria Marcella Plummer Jan 2010

Job Seeking And Job Application In Social Networking Sites : Predicting Job Seekers' Behavioral Intentions, Maria Marcella Plummer

Dissertations

Social networking sites (SNSs) are revolutionizing the way in which employers and job seekers connect and interact with each other. Despite the reported benefits of SNSs with respect to finding a job, there are issues such as privacy concerns that might be deterring job seekers from using these sites in their attempts to secure a job. It is therefore important to understand the factors that are salient in predicting job seekers' use of SNSs in applying for jobs.

In this research, a theoretical model was developed to explicate job seekers' intentions to use SNSs to apply for jobs. Two aspects …


Optimal Synthesis Of Planar Adjustable Mechanisms, Chong Peng Jan 2010

Optimal Synthesis Of Planar Adjustable Mechanisms, Chong Peng

Dissertations

Adjustable mechanisms provide degrees of flexibility while retaining desirable features of one degree of freedom close-loop mechanisms, such as simplicity, stability, and high speed capabilities. By adjusting linkage parameters, additional phases of motions can be achieved using the same hardware. However, an adjustment to the mechanism adds only one or two additional design positions and divides desired positions into "phases", each of which contains only a few positions usually insufficient for industrial applications.

In order to extend the design position limitation of adjustable mechanisms, an optimal synthesis method based on link length structural error is developed and applied to kinematic …


Soft-Error Resilient On-Chip Memory Structures, Shuai Wang Jan 2010

Soft-Error Resilient On-Chip Memory Structures, Shuai Wang

Dissertations

Soft errors induced by energetic particle strikes in on-chip memory structures, such as L1 data/instruction caches and register files, have become an increasing challenge in designing new generation reliable microprocessors. Due to their transient/random nature, soft errors cannot be captured by traditional verification and testing process due to the irrelevancy to the correctness of the logic. This dissertation is thus focusing on the reliability characterization and cost-effective reliable design of on-chip memories against soft errors.

Due to various performance, area/size, and energy constraints in various target systems, many existing unoptimized protection schemes on cache memories may eventually prove significantly inadequate …


Adaptive Trust And Reputation System As A Security Service In Group Communications, Pitipatana Sakarindr Jan 2010

Adaptive Trust And Reputation System As A Security Service In Group Communications, Pitipatana Sakarindr

Dissertations

Group communications has been facilitating many emerging applications which require packet delivery from one or more sender(s) to multiple receivers. Owing to the multicasting and broadcasting nature, group communications are susceptible to various kinds of attacks. Though a number of proposals have been reported to secure group communications, provisioning security in group communications remains a critical and challenging issue.

This work first presents a survey on recent advances in security requirements and services in group communications in wireless and wired networks, and discusses challenges in designing secure group communications in these networks. Effective security services to secure group communications are …


Semantics And Efficient Evaluation Of Partial Tree-Pattern Queries On Xml, Xiaoying Wu Jan 2010

Semantics And Efficient Evaluation Of Partial Tree-Pattern Queries On Xml, Xiaoying Wu

Dissertations

Current applications export and exchange XML data on the web. Usually, XML data are queried using keyword queries or using the standard structured query language XQuery the core of which consists of the navigational query language XPath. In this context, one major challenge is the querying of the data when the structure of the data sources is complex or not fully known to the user. Another challenge is the integration of multiple data sources that export data with structural differences and irregularities. In this dissertation, a query language for XML called Partial Tree-Pattern Query (PTPQ) language is considered. PTPQs generalize …


Synthesis And Characterization Of Metal Oxide Semiconductors For Photoelectrochemical Hydrogen Production, Sudhakar Shet Jan 2010

Synthesis And Characterization Of Metal Oxide Semiconductors For Photoelectrochemical Hydrogen Production, Sudhakar Shet

Dissertations

The goal of this thesis is to investigate the properties of metal-oxide thin films on fluorine-doped tin oxide (FTO)-coated glass substrates, prepared by using radio- frequency (RF) reactive magnetron sputtering for photoelectrochemical (PEC) applications. Metal-oxide thin films as a photoelectrode are of special interest for PEC systems to produce hydrogen in an aqueous solution by solar energy due to their low cost and potential stability.

The following list represents some of the accomplishments and results of this work:

  • Narrowing of N-incorporated ZnO (ZnO:N) was achieved by reactive sputtering in a O2/N2 mixture ambient, and ZnO:N films with …


Institutional Controls And Brownfield Redevelopment, Ronnachai Tiyarattanachai Jan 2010

Institutional Controls And Brownfield Redevelopment, Ronnachai Tiyarattanachai

Dissertations

Institutional controls (ICs) are used to reduce risks to human health and environment from exposure to contaminants at Brownfield sites. Regulators approve use of ICs in Brownfield redevelopment with the expectation that ICs will remain effective over the long-term under proper oversight mechanisms. However, a recent review of compliance statuses of Brownfield sites with ICs implemented in Massachusetts and New Jersey indicated a significant percentage of the sites are out of compliance status.

Implementation of ICs depends on compliance efforts by humans. Thus, consistency of implementation over the long-term is questionable because there are several potential problems due to human …


Modeling And Quasi-Monte Carlo Simulation Of Risk In Credit Portfolios, Bo Ren Jan 2010

Modeling And Quasi-Monte Carlo Simulation Of Risk In Credit Portfolios, Bo Ren

Dissertations

Credit risk is the risk of losing contractually obligated cash flows promised by a counterparty such as a corporation, financial institution, or government due to default on its debt obligations. The need for accurate pricing and hedging of complex credit derivatives and for active management of large credit portfolios calls for an accurate assessment of the risk inherent in the underlying credit portfolios. An important challenge for modeling a credit portfolio is to capture the correlations within the credit portfolio. For very large and homogeneous portfolios, analytic and semi-analytic approaches can be used to derive limiting distributions. However, for portfolios …


Generalized Discrete Fourier Transform With Non-Linear Phase : Theory And Design, Handan Agirman-Tosun Jan 2010

Generalized Discrete Fourier Transform With Non-Linear Phase : Theory And Design, Handan Agirman-Tosun

Dissertations

Constant modulus transforms like discrete Fourier transform (DFT), Walsh transform, and Gold codes have been successfully used over several decades in various engineering applications, including discrete multi-tone (DMT), orthogonal frequency division multiplexing (OFDM) and code division multiple access (CDMA) communications systems. Among these popular transforms, DFT is a linear phase transform and widely used in multicarrier communications due to its performance and fast algorithms. In this thesis, a theoretical framework for Generalized DFT (GDFT) with nonlinear phase exploiting the phase space is developed. It is shown that GDFT offers sizable correlation improvements over DFT, Walsh, and Gold codes. Brute force …


Motion Coordination And Control In The Development Of A Gait Rehabilitation System, Yazan Ahmad Manna Jan 2010

Motion Coordination And Control In The Development Of A Gait Rehabilitation System, Yazan Ahmad Manna

Dissertations

While most take their ability to walk for granted, some are unable to walk due to any number of pathologies, such as traumatic brain injury (TBI), spinal cord injury (SCI), and Parkinson's disease. Decreased activity has been shown to be associated with rapidly deconditioning. Rehabilitation techniques that afford patients the ability to begin reconditioning through walking sooner may ultimately enhance their return to a better quality of life. To assist the functional recovery of such patients, an appropriate afferent input to the spinal cord will help in the therapy of the patient. Manual training is labor intensive, costly, and ergonomically …


Virtual World Commerce Adoption (Vwca) : A Case Study Of Second Life Investigating The Impacts Of Perceived Affordances, Trust, And Need Satisfaction, Kamolbhan Olapiriyakul Jan 2010

Virtual World Commerce Adoption (Vwca) : A Case Study Of Second Life Investigating The Impacts Of Perceived Affordances, Trust, And Need Satisfaction, Kamolbhan Olapiriyakul

Dissertations

Virtual worlds are computer-simulated worlds in which multi-players can simultaneously interact in a rich graphical environment. The development of virtual worlds, along with the massive growth of users, creates opportunities for business organizations. This dissertation involves many studies regarding virtual world adoption in business by virtual consumers.

Most of the research in Information Systems (IS) was conducted investigating factors influencing technology adoption, such as ease of use and usefulness, subjective norms and behavioral controls, self-efficacy, performance and effort expectancy, flow, etc. However, most of these research studies focused neither on design aspects related to affordances nor users' goal-oriented behaviors, such …


Advanced Classification Of Ofdm And Mimo Signals With Enhanced Second Order Cyclostationarity Detection, Miao Shi Jan 2010

Advanced Classification Of Ofdm And Mimo Signals With Enhanced Second Order Cyclostationarity Detection, Miao Shi

Dissertations

With the emergence of cognitive radio and the introduction of new modulation techniques such as OFDM and MIMO, the problem of Modulation Classification (MC) becomes more challenging and complicated. In the first part of the thesis, we explore the automatic modulation classification to blindly distinguish OFDM from single carrier signals. We use the fourth order cumulants; an approach which in the past has been also applied to classify single carrier signals. A blind OFDM parameter estimation scheme was then followed, which includes the estimation of number of subcarriers, CP length, timing and frequency offset and the oversampling factor for the …


Booklet Of Selected Theses From The Ma In Criminology, Ma In Law, And Ma In Child, Family And Community Studies 2007- 2009., Kevin Lalor, Claire Hamilton, Fergus Ryan, Brian Mccarthy Jan 2010

Booklet Of Selected Theses From The Ma In Criminology, Ma In Law, And Ma In Child, Family And Community Studies 2007- 2009., Kevin Lalor, Claire Hamilton, Fergus Ryan, Brian Mccarthy

Dissertations

No abstract provided.


Where The Rocks Are In The Pond : Using Critical Race Theory To Gain Access To More Equitable Educational Opportunities For African Americans, Thomasina F. Hassler Jan 2010

Where The Rocks Are In The Pond : Using Critical Race Theory To Gain Access To More Equitable Educational Opportunities For African Americans, Thomasina F. Hassler

Dissertations

“Where the rocks are in the pond” is a metaphor for the concept of empowerment so that those who have traditionally been marginalized and isolated, typically people of color and the poor, can learn the normative strategies that the dominant culture accesses to success. Developmentally, members of marginalized populations are harmed by the lack of access to quality resources for social, economic, political and educational growth. I have chosen autoethnography as the vehicle to carry critical events that illuminate the deleterious effects of racialization in U. S. society. The study used critical race theory as the theoretical lens to analyze …


Xperts And Novices: Differences In Their Use Of Mental Representation And Metacognition In Engineering Design, Raymond Anthony Dixon Jan 2010

Xperts And Novices: Differences In Their Use Of Mental Representation And Metacognition In Engineering Design, Raymond Anthony Dixon

Dissertations

Research shows that mental representation such as analogical reasoning is a fundamental cognitive tool for design problem solving (Daugherty & Mentzer, 2008; Hey, Lensey, Agogino, & Wood, 2008; Lewis, 2008). Not much is known, however, about the way students and professional engineers actively generate and change their mental representation when solving a engineering design problem. There are very few studies that show how different types of mental representations; such as metaphors, propositions, and analogies; interplay with higher order cognitive processes; such as planning, monitoring, and evaluation; as engineering designers navigate their problem and solution spaces. This empirical study investigated the …


Examining The Role Of Meaning-Making And Cultural Competence In How Teachers Understand And Approach Their Work With Culturally And Linguistically Diverse Students, Sarina Chugani Molina Edd Jan 2010

Examining The Role Of Meaning-Making And Cultural Competence In How Teachers Understand And Approach Their Work With Culturally And Linguistically Diverse Students, Sarina Chugani Molina Edd

Dissertations

The tapestry of classrooms today is transforming into a mosaic of colors, languages, and backgrounds. As the population of culturally and linguistically diverse (CLD) students continues to rise, a deeper understanding of how teachers construct meaning and understand their internal and relational experiences when working with these students has become an important area to examine. The purpose of this study was to gain a deeper understanding of teachers' meaning-making systems and their cultural competence as it relates to their work with CLD students. Kegan (1982, 1994) provides a constructive developmental lens, which was used in this study, to understand how …


Women And Authority: Transitioning Into A Role Of Assigned Authority As A Graduate Teaching Assistant In A Leadership Class, Lorri L. Sulpizio Phd Jan 2010

Women And Authority: Transitioning Into A Role Of Assigned Authority As A Graduate Teaching Assistant In A Leadership Class, Lorri L. Sulpizio Phd

Dissertations

Women are assuming positions with significant formal authority, yet women still remain underrepresented in many areas of the public sector (Kellerman & Rhode, 2007). Additionally, women in formal positions of authority have increased opportunities to exercise leadership and address challenges while mobilizing people toward change. Formal positions of authority include the role of mother, schoolteacher, senator, or senior executive. It is rare for women to receive any practice for the authority roles they assume and as such may find the roles accompanied by interactions and processes that are unfamiliar to them. The role of Graduate Teaching Assistant (GTA) provides women …


An Investigation Of The Test-Taking Skills And Associated Thinking Processes Of Ninth Grade English Language Arts Students, Mary B. O'Shea Edd Jan 2010

An Investigation Of The Test-Taking Skills And Associated Thinking Processes Of Ninth Grade English Language Arts Students, Mary B. O'Shea Edd

Dissertations

Although much is known about how students perform on standardized tests, little research exists concerning how students think and process while taking such tests. This mixed methods action research study was designed to investigate if a constructivist approach to test preparation could yield improved results for 37 English language arts freshmen preparing for the California High School Exit Exam (CAHSEE). The researcher explored student performances on Princeton Review practice CAHSEE tests (versions A, B, and C) over a 3-month period and she performed several statistical tests including repeated measures ANOVA by individual classes (advanced, basic, below basic) to determine differences …


Course Design Based On The Kolb Learning Style As It Relates To Student Success In Online Classes, Edward John Perantoni Jan 2010

Course Design Based On The Kolb Learning Style As It Relates To Student Success In Online Classes, Edward John Perantoni

Dissertations

Educators are taught that differentiated instruction is important to ensuring that students are offered an opportunity to learn. As a result, student learning styles become important in the design of an online course. Certain students prefer group work, discussions, and brainstorming sessions all of which are part of the socialization process. Kolb related the ability of a student to learn through the socialization process to the accommodator and diverger learning styles. The researcher hypothesized that the development of a quality online course, as defined by NACOL, should include socialization techniques such as group work. Therefore, the purpose of this study …


The Use Of Classroom Walk-Through Observations As A Strategy To Improve Teaching And Learning: An Administrative Perspective, Mark J. Weller Jan 2010

The Use Of Classroom Walk-Through Observations As A Strategy To Improve Teaching And Learning: An Administrative Perspective, Mark J. Weller

Dissertations

The purpose of this study was to identify the possible use of structured classroom walk-through observations as a strategy to improve teaching and learning. A wide variety of programs and initiatives have recently been implemented across the country to improve student achievement. One such initiative is classroom walk-through observations. Classroom walk-through observations are briefly performed by school administrators to gauge the effectiveness of instruction in each classroom. The walkthrough observation gives teachers and administrators a snapshot of teaching and learning aspects throughout the school over time. This research was done collaboratively with Leslie McEntire and Tom Sorensen. The research team …