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Theses/Dissertations

2009

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Institution
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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 Dec 2009

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 "initial and ...


Optimal Synthesis Of Planar Adjustable Mechanisms, Chong Peng Dec 2009

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 ...


Job Seeking And Job Application In Social Networking Sites : Predicting Job Seekers' Behavioral Intentions, Maria Marcella Plummer Dec 2009

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 ...


Generalized Discrete Fourier Transform With Non-Linear Phase : Theory And Design, Handan Agirman-Tosun Dec 2009

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 ...


Understanding Cognitive Differences In Processing Competing Visualizations Of Complex Systems, Madhavi Mukul Chakrabarty Dec 2009

Understanding Cognitive Differences In Processing Competing Visualizations Of Complex Systems, Madhavi Mukul Chakrabarty

Dissertations

Node-link diagrams are used represent systems having different elements and relationships among the elements. Representing the systems using visualizations like node-link diagrams provides cognitive aid to individuals in understanding the system and effectively managing these systems. Using appropriate visual tools aids in task completion by reducing the cognitive load of individuals in understanding the problems and solving them. However, the visualizations that are currently developed lack any cognitive processing based evaluation. Most of the evaluations (if any) are based on the result of tasks performed using these visualizations. Therefore, the evaluations do not provide any perspective from the point of ...


End-Of-Life Analysis Of Nanotechnology Products, Sun Olapiriyakul Dec 2009

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 ...


Operating Characteristics Of Passenger Screening Processes And The Development Of A Paced Inspection System, Geraldine Kelly Leone Dec 2009

Operating Characteristics Of Passenger Screening Processes And The Development Of A Paced Inspection System, Geraldine Kelly Leone

Dissertations

The airport checkpoint security screening (ACSS) system is an important line of defense against the introduction of dangerous objects into the U.S. aviation system. Recently, there has been much interest in modeling these systems and to derive operating parameters which optimize performance. In general there are two performance measures of interest (i) the waiting time of the arriving entities, and (ii) the allocated screening resources and its utilization. Clearly, the traveling public would like a zero waiting time, while airports are limited both in terms of space and resource capital. The arrival and exit entity in the ACSS system ...


Perturbed Spherical Objects In Acoustic And Fluid Flow Fields, Manmeet Kaur Dec 2009

Perturbed Spherical Objects In Acoustic And Fluid Flow Fields, Manmeet Kaur

Dissertations

In this study, the time averaged acoustic radiation force and drag on a small, nearly spherical object suspended freely in a stationary sound wave field in a compressible, low viscosity fluid is to be calculated. This problem has been solved for a spherical object, and it has many important engineering applications related to segregation and separation processes for particles in fluids such as water. Small but significant errors have occurred in the predicted behavior of the particles using the existing approximate solutions based on perfect spheres. The classical approach has been extended in this research to objects that deviate slightly ...


Integration Of Electronic And Optical Techniques In The Design And Fabrication Of Pressure Sensors, Ivan Padron Dec 2009

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 ...


Advanced Classification Of Ofdm And Mimo Signals With Enhanced Second Order Cyclostationarity Detection, Miao Shi Dec 2009

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 ...


Semantics And Efficient Evaluation Of Partial Tree-Pattern Queries On Xml, Xiaoying Wu Dec 2009

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 ...


Institutional Controls And Brownfield Redevelopment, Ronnachai Tiyarattanachai Dec 2009

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 ...


Soft-Error Resilient On-Chip Memory Structures, Shuai Wang Dec 2009

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 ...


Relationship Between Photospheric Magnetic Fields And Coronal Activities, Changyi Tan Dec 2009

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 ...


Algorithms In Comparative Genomics, Satish Chikkagoudar Dec 2009

Algorithms In Comparative Genomics, Satish Chikkagoudar

Dissertations

The field of comparative genomics is abundant with problems of interest to computer scientists. In this thesis, the author presents solutions to three contemporary problems: obtaining better alignments for phylogeny reconstruction, identifying related RNA sequences in genomes, and ranking Single Nucleotide Polymorphisms (SNPs) in genome-wide association studies (GWAS).

Sequence alignment is a basic and widely used task in bioinformatics. Its applications include identifying protein structure, RNAs and transcription factor binding sites in genomes, and phylogeny reconstruction. Phylogenetic descriptions depend not only on the employed reconstruction technique, but also on the underlying sequence alignment. The author has studied and established a ...


Target Localization In Mimo Radar Systems, Hana Godrich Dec 2009

Target Localization In Mimo Radar Systems, Hana Godrich

Dissertations

MIMO (Multiple-Input Multiple-Output) radar systems employ multiple antennas to transmit multiple waveforms and engage in joint processing of the received echoes from the target. MIMO radar has been receiving increasing attention in recent years from researchers, practitioners, and funding agencies. Elements of MIMO radar have the ability to transmit diverse waveforms ranging from independent to fully correlated. MIMO radar offers a new paradigm for signal processing research. In this dissertation, target localization accuracy performance, attainable by the use of MIMO radar systems, configured with multiple transmit and receive sensors, widely distributed over an area, are studied. The Cramer-Rao lower bound ...


Optimal Train Control On Various Track Alignments Considering Speed And Schedule Adherence Constraints, Kitae Kim Dec 2009

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 ...


Motion Coordination And Control In The Development Of A Gait Rehabilitation System, Yazan Ahmad Manna Dec 2009

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 ...


Resource Assignment In Short Life Technology Intensive (Slti) New Product Development (Npd), Randy A. Reagan Dec 2009

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 ...


Service Oriented Networking For Multimedia Applications In Broadband Wireless Networks, Ehsan Haghani Dogaheh Dec 2009

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 Dec 2009

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 ...


Virtual World Commerce Adoption (Vwca) : A Case Study Of Second Life Investigating The Impacts Of Perceived Affordances, Trust, And Need Satisfaction, Kamolbhan Olapiriyakul Dec 2009

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 ...


Synthesis And Characterization Of Metal Oxide Semiconductors For Photoelectrochemical Hydrogen Production, Sudhakar Shet Dec 2009

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 ...


Nonlinear Evolution Of Annular Layers And Liquid Threads In Electric Fields, Qiming Wang Dec 2009

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 ...


Cooperative Retransmission Protocols In Fading Channels : Issues, Solutions And Applications, Igor Stanojev Dec 2009

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 ...


Adaptive Trust And Reputation System As A Security Service In Group Communications, Pitipatana Sakarindr Dec 2009

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 ...


Modeling And Quasi-Monte Carlo Simulation Of Risk In Credit Portfolios, Bo Ren Dec 2009

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 ...


Development Of Pharmacophore And Comfa Study Of Rigid And Flexible Sigma 2 Receptor Ligands, Hemantbhai Patel Dec 2009

Development Of Pharmacophore And Comfa Study Of Rigid And Flexible Sigma 2 Receptor Ligands, Hemantbhai Patel

Theses

In the present study a pharmacophore and CoMFA model was derived for sigma 2 (62) receptors by using Sybyl 7.2 Software Package. The CoMFA studies used 22 bioactive molecules as a training set and 4 molecules as a test set for the o2 receptor ligands. The geometries and electrostatic charges of all molecules were calculated using various levels of calculations. The geometry optimization and electrostatic charges of all 26 molecules were performed by using semiemprical AM1, ab initio HF/6-31G* and density functional B3LYP/6-31G* in Gaussian 98. The pharmacophore model was derived by using Distance Comparisions (DISCOtech) from ...


Development Of A Device For Whole Body Stimulation Of The Otoliths, Jon Edward Weimer Dec 2009

Development Of A Device For Whole Body Stimulation Of The Otoliths, Jon Edward Weimer

Theses

Over the past few decades, research has been conducted to explore the effects of microgravity on human musculature, As seen in astronauts upon their return to Earth after prolonged spaceflight, extensive muscle atrophy due to adaptation to conditions of microgravity many times decreases a person's ability to walk or even stand, With an understanding of the anatomical mechanisms that provide postural control, the proper stimulation, resulting in a reduction in spasticity, could be provided by simulating these conditions of microgravity.

In order to simulate microgravity, a device has been developed that is capable of providing whole body stimulation of ...


“Make It Happen With Momentum”, Stavros Michailidis Dec 2009

“Make It Happen With Momentum”, Stavros Michailidis

Creative Studies Graduate Student Master's Projects

The “Make it Happen with Momentum” workshop is a 90 minute interactive experience developed for the 11th Annual European Conference on Creativity and Innovation. It was first presented on October 29, 2009 in Brussels, Belgium by Stavros Michailidis and Donald M. Drost, Phd. The workshop was well received and selected amongst the best workshops of the conference.

The purpose of the workshop is to introduce participants to the Momentum Framework, developed by Stavros Michailidis to diagnose and nurture the successful implementation of creative works. Work to date includes a formula for momentum, a diagnostic tool for assessing momentum and basic ...