Digital Commons Network^™

An Automata-Based Automatic Verification Environment, Yi Meng

Dissertations

With the continuing growth of computer systems including safety-critical computer control systems, the need for reliable tools to help construct, analyze, and verify such systems also continues to grow. The basic motivation of this work is to build such a formal verification environment for computer-based systems.

An example of such a tool is the Design Oriented Verification and Evaluation (DOVE) created by Australian Defense Science and Technology Organization. One of the advantages of DOVE is that it combines ease of use provided by a graphical user interface for describing specifications in the form of extended state machines with the rigor …

On The Design For Flexibility Of Manufacturing Systems : A Stochiastic Approach, Nathapol Areeratchakul

Dissertations

Flexibility has emerged as one of the most strategic imperatives for company viability in today's fast paced economy. This realization has stimulated extensive research efforts in this area most of which have focused mainly on defining flexibility and its attributes, the need for flexibility and how to measure it. Nevertheless, despite the considerable amount of publications regarding flexibility and its related subjects, insufficient attention has been given to the optimality of the design for flexibility and the inherent needs to meet uncertainty. Bridging this gap is the intent of this work.

In this dissertation, developed analytical models are for the …

Development Of Micro-Scale And Automated Membrane Extraction Systems For Water Analysis, Xiaoyan Wang

Dissertations

Monitoring of trace level contaminants in water involves the extraction and enrichment of analytes. Over the years several techniques have been developed for this purpose. Currently there is an urgent need for the development of micro-scale extraction techniques that can lead to simple, fast trace analysis. Automated instruments that can be used for continuous, on-line analysis are also important. Membrane extraction can address both these needs, because it can be carried out in a continuous fashion and can also be miniaturized. This research addresses these two aspects of membrane extraction for the next generation of sample preparation.

Micro-Scale Membrane Extraction: …

Effect Of Heavy Metals On Salt March Biota, Kallaya Suntornvongsagul

Dissertations

Environmental restoration of disturbed, degraded and potentially contaminated wetland sites aims for the persistent and sustainable re-establishment of biological communities and important wetland functions. An ecologically informed restoration strategy presupposes some understanding of these system processes, but also of potential impacts on contaminants in the environment for risk assessment, long-term management, and potential cost-effective mitigative measures. In this study, potential effects of moderate heavy metal contamination in sediments of the urban salt marsh Harrier Meadow, NJ, were evaluated on growth performance of the common salt marsh plant S. patens and associated arbuscular mycorrhizal fungi (AMF) colonizing its roots. Growth performance …

Functionalization, Growth And Applications Of Single Wall Carbon Nanotubes, Yubing Wang

Dissertations

Because of their remarkable structural, mechanical and electrical properties, carbon nanotubes, and especially single wall carbon nanotubes (SWNTs), represent one of the most widely investigated materials today in the emerging field of nanotechnology. The development of oriented growth of SWNTs critical for applications, novel approaches for the creation of functional SWNTs, and applications of both as-prepared and chemically functionalized SWNTs for electrochemically-induced hydrogen storage, in-situ formation of new polymer and ceramic nanocomposites with SWNTs, and the fabrication and study for the first time, to the best of our knowledge, of a SWNT-based biofuel cell and self-powered biosensor, are the thrusts …

A Bayesian Approach To Wireless Location Problems, Ivan Zorych

Dissertations

Several approaches for indoor location estimation in wireless networks are proposed. We explore non-hierarchical and hierarchical Bayesian graphical models that use prior knowledge about physics of signal propagation, as well as different modifications of Bayesian bivariate spline models. The hierarchical Bayesian model that incorporates information about locations of access points achieves accuracy that is similar to other published models and algorithms, but by using prior knowledge, this model drastically reduces the requirement for training data when compared to existing approaches. Proposed Bayesian bivariate spline models for location surpass predictive accuracy of existing methods. It has been shown that different versions …

Studies Of Solar White-Light Flares And Small-Scale Magnetic Structures Observed In The Near Infrared, Yan Xu

Dissertations

Using the most advanced infrared imaging technology as developed by NJIT, detailed study of solar white-light flares and small magnetic structures, such as faculae and pores, are presented in this dissertation. The investigations focus on near-infrared observations at 1.56 μm, which are good proxy of the deepest layer of the solar photosphere.

I made fundamental contributions in two areas of near infrared (NIR) solar physics: (1) the first detection and understanding of white-light flares in the NIR and (2) clearly demonstrated non-existence of "dark faculae". Several high-resolution observations have been carried out at BBSO and National Solar Observatory/Sacramento Peak. The …

Supporting Individual Time Management Through The Capture And Display Of Temporal Structures, Dezhi Wu

Dissertations

This thesis work examines the time management strategies of individuals in an academic institution and gathers information on the complex temporal structures they experience and manage. Its focus is on understanding the relationship between the quality of individual time management and an individual's understanding and use of temporal structures. This work consists of an exploratory field study to gather data on how people use temporal structures with electronic tools. It is followed by a survey that is given to a larger group of respondents in the same subject population examined with the field study. The survey examines the hypotheses developed …

Rna Structure Analysis : Algorithms And Applications, Jianghui Liu

Dissertations

In this doctoral thesis, efficient algorithms for aligning RNA secondary structures and mining unknown RNA motifs are presented. As the major contribution, a structure alignment algorithm, which combines both primary and secondary structure information, can find the optimal alignment between two given structures where one of them could be either a pattern structure of a known motif or a real query structure and the other be a subject structure.

Motivated by widely used algorithms for RNA folding, the proposed algorithm decomposes an RNA secondary structure into a set of atomic structural components that can be further organized in a tree …

Electronic Capture And Analysis Of Fraudulent Behavioral Patterns : An Application To Identity Fraud, Benjamin Ngugi

Dissertations

The objective of this research was to find a transparent and secure solution for mitigating identity fraud and to find the critical factors that determine the solution's acceptance. Identity fraud is identified as a key problem with total losses exceeding fifty two billion dollars (Javelin Strategy and Research 2005). A common denominator in most identity-fraud-prone transactions is the use of a keypad; hence this research focuses on keypad data entry and proposes a biometric solution. Three studies develop, evaluate and investigate the feasibility of this solution.

The first study was done in three stages. Stage one investigated the technical feasibility …

Navigating Cultures And Epistemologies In Science And Technology Education, Kathleen Theresa Kurzk

Dissertations

This investigation focuses on the nexus of science and culture in the lives of marginalized youth in the United States and South Africa. The epistemologies and contextual realities of cross-cultural learner cohorts and their understandings of scientific phenomena are examined. The researcher was a participant observer within the context of the Science, Technology & Culture: Empowering Learners (STC) program, an after-school and school-based collaboration focused upon integrating science, technology and culture. Electronic communication provided a vehicle for dialogue between youth in St. Louis, Missouri, USA and a South African Township. Study findings include documentation of the marginalizing effects of poverty …

How High School Science-Related Experiences Influenced Career Persistence, Andrew Dwight Shaw

Dissertations

The events of 9/11 brought into focus two ongoing trends that were present before this tragedy and have continued since: 1) The United States needs more scientists if it is to ensure its freedoms and maintain its economy. 2) The number of scientists in the ¿pipeline¿ is declining because of the diminished presence of foreign scientists (they are wanted in their own countries), the under-representation of minorities and women, and the reduced numbers of students able and willing to take on the scholastic rigors necessary for a science or engineering degree. Though much has been written about improving science education, …

An Analysis Of Rhythm Systems In The United States: Their Development And Frequency Of Use By Teachers, Students, And Authors; And Relation To Perceived Learning Preferences, Paul Charles Varley

Dissertations

One of the issues facing music educators is the way in which they teach students to read rhythms accurately. Using the current educational philosophy of differentiation, or teaching a student by appealing to their preferred learning style, as a backdrop, the researcher proposed that music educators tend to teach rhythms using a limited number of systems, thereby failing to utilize many of the available systems.

The researcher examined the published rhythm systems dating back to the early nineteenth century, surveyed band students in grades 7-12 concerning their preferences in learning rhythms and their learning styles, surveyed music teachers concerning their …

Alice Parker: American Choral Composer, Arranger, And Educator, Gail H. Fleming

Dissertations

This investigation is an in-depth examination of Alice Parker's philosophy of music in relation to choral teaching, arranging, and composing. The researcher proposes that within the context of multi-cultural American music, Alice Parker's unique approach to music making and how it is manifested within her choral compositions, arrangements, and teaching techniques is a significant and valuable area of study for music educators and students. Further, it is beneficial to administrators and the general public, as well.

Within the literature review, Alice Parker's unique and effective approach to music making is related to the need for a philosophy of music, educational …

Influence Of Uncorrelated Defects On The Vortex Phase Diagram In Yba2Cu3O7-6 Superconducting System, Lucian M. Undreiu

Dissertations

The goal of our work is to gain more insight into the vortex dynamics in YBa₂Cu₃0_7-8 single crystals with point defects induced by 9MeV proton irradiation. The position of the critical points from the first order melting transition line can be shifted in a controlled manner with the induced disorder. In order to accomplish a comparative study, different crystals and irradiation doses were used. The results were correlated using both electrical transport and ac specific heat measurements. Special attention was given to investigating the nature of the vortex state below the lower critical point o …

Evaluating The Operative Mechanisms Underlying The High-Probability Request Sequence, Carrie L. Coleman

Dissertations

Failure to comply with requests in educational settings interferes with the learning process. The high-probability request sequence has been demonstrated to be an effective treatment for noncompliance. However, the operative mechanisms underlying this treatment remain unknown. This study sought to further elucidate high-p behavior change mechanisms through the manipulation of reinforcement and response rate variables. The purpose was to determine whether increases in compliance to low-probability requests could be obtained with either the high-p sequence or with the delivery of preferred stimuli on a response-independent basis. Math problems served as high-p and low-p requests, and data were collected on compliance …

Relationship Between Course-Taking Behavior, Gender, And Mathematics Achievement On The Missouri Assessment Program (Map), Geraldine Dressel Baumgart

Dissertations

This study examined the relationship between student course taking, specifically the year of Algebra completion (grade 8, 9, 10, or not completed), and performance on the Missouri Assessment Program (MAP) mathematics test in grades 8 and 10. Data collected were student scores on the MAP tests, TerraNova tests in Communication Arts and Mathematics, student math grades, and demographic factors of gender and race. The sample of 512 students was taken from one school district in east central Missouri.

The MAP mathematics tests contain 3 item types. Item type was statistically significant with both males and females scoring highest on Multiple …

High School Seniors’ Perceptions Of Career And Technical Education And Factors Influencing Their Decision To Attend An Area Career Technical Center, David P. Gaunt

Dissertations

This study explored the profile of CTE students with regard to their academic standing and their socioeconomic background, examined high school seniors'perceptions of career and technical education, and identified the people and other factors that influence students in their decision-making about CTE enrollment. A 29-question survey was administered to 451 seniors from seven public high schools served by the Wexford-Missaukee Area Career Technical Center, operated by an intermediate school district in northern lower Michigan.

Significant findings indicate that the typical profile of CTE students with respect to socioeconomic status and academic standing would identify a CTE student as performing somewhat …

Acylpyrazolones: Synthesis, Self-Assembly And Lanthanide Metal Ion Separation, Jun Yang

Dissertations

The central hypothesis that nanoscale self-assemblies can provide excellent metal ion recognition has been substantiated by employing acylpyrazolones and trivalent lanthanide metal ions as model systems. Several novel acylpyrazolones and their amphiphilic analogs have been designed, synthesized, and characterized. Their lanthanide metal ion recognition efficacies have been demonstrated through baseline separations of a mixture of light, middle, and heavy lanthanide metal ions by employing them in the aqueous mobile phase of high performance liquid chromatography (HPLC) with octadecylsilanized silica (ODS) as the stationary phase. The complex separation mechanism is influenced by the structures of acylpyrazolone and amphiphilic moieties, and spontaneous …

Load Interaction Effects On Fatigue Crack Growth, Stoyan Ivanov Stoychev

Dissertations

Load excursions, in the form of tensile and compressive overloads are known to produce interaction effects during subsequent constant amplitude loading. In this work, the fatigue crack growth and crack closure levels, under both constant amplitude and variable amplitude loading, are investigated in the aluminium-lithium alloy 2090-T84, and the aluminium alloys 2024-T351 and 7150-T651. The crack closure measurements were obtained using both a crack tip opening displacement (CTOD) gauge and a crack mouth opening displacement (CMOD) gauge.

Fatigue crack growth tests were performed on specimens of thickness 1.6mm, 3mm, 6mm and 14mm. Tests were performed at load ratios of 0.1 …

Synthesis And Spectroscopic Characterization Of Manganese Doped Zinc Sulfide Quantum Dot Nanocrystals, Pedro A. Gonzalez Beerman

Dissertations

Zinc sulphide quantum dots were synthesized in aqueous media using sodium polyphosphate as the stabilizer. The nanoparticles were 2.5 ± 0.5 nm and 5.0 ± 0.5 nm diameter depending on the synthetic procedure employed and the amount of Mn doped varied from 0.003 to 0.32% (w/w). The nanoparticles were characterized by UV-Vis absorption, luminescence, EPR, near edge x-ray absorption fine structure (NEXAFS), and x-ray photoelectron spectroscopy (XPS), and x-ray diffraction (XRD), and transmission electron microscopy (TEM). These quantum dots show a strong emission at 590 nm due to the ⁴T₁ -⁶A₁ transition characteristic of Mn …

Development Of An Analogue Of A Response-Class Hierarchy, Daniel B. Shabani

Dissertations

Within the operant conditioning literature, there exists the concept of the functional response class. A functional response class is defined as a collection of responses that all produce the same outcome. If the members of a response class occur in a predictable order, a response-class hierarchy is said to exist. A hierarchy refers to a specific type of response class in which each member of the response class may be temporally determined along various dimensions (e.g., response effort, immediacy of reinforcement, magnitude of reinforcer). The response-class hierarchy has received relatively little conceptual attention over the years and, not surprisingly, there …

Single-Electron Capture Processes In Slow Collisions Of He^2+ Ions With Molecular Targets, Osama Abu-Haija

Dissertations

Translational energy-gain spectroscopy (TES) has been used to investigate state-selective dissociative and non-dissociative single-electron capture processes in low-energy collisions of He²⁺ ions with O₂ , H₂ O, CO₂ , N₂ , and NH3 at impact energies between 100 eV and 1600 eV. The measured energy spectra for theHe²⁺ -O₂ and H₂ O collision systems show that the dominant exit channel is due to dissociative transfer ionization (DTI), single-electron captureaccompanied by ionization of the molecular target-ion, at the lowest collision energies. As the impact energy is increased non-dissociative single-electron capture (SEC) into the …

Rank-Based Methods For Repeated Measures Data Under Exchangeable Errors, John Kloke

Dissertations

Rank-based estimation methods provide alternatives to least squares. Estimators derived via least squares are generally not robust to aberrant observations.Rank-based methods for linear models generalize traditional Wilcoxon procedures in the simple location models and are robust.

In the usual linear model it is assumed that the errors are independent. In the case of repeated measures data several observations are taken on each experimental unit. In the case of longitudinal data the measures are taken on the same subject over time. As such an independence assumption does not seem valid. A common solution to this is to make an assumption on …

Modeling Of Flexible Drug-Like Molecules : Qsar Of Gbr 12909 Analog Dat/Sert Selectivity, Kathleen Mary Gilbert

Dissertations

The dopamine reuptake inhibitor GBR 12909 and related dialkyl piperazine and piperidine analogs have been studied as agonist substitution therapies acting on the dopamine transporter (DAT) to treat cocaine addiction. Undesirable binding to the serotonin transporter (SERT) can vary greatly depending on the specific substituents on the molecule. This study uses Comparative Molecular Field Analysis (CoMFA) and Comparative Molecular Similarity Indices (CoMSIA) techniques to determine a stable and predictive model for DAT/SERT selectivity for a set of flexible GBR 12909 analogs.

Families of analogs were constructed from six pairs of naphthyl-substituted piperazine and piperidine templates identified by hierarchical clustering as …

Influences Of Surfactant On The Breakup Of A Fluid Jet In Viscous Surrounding, Muhammad Irfan Hameed

Dissertations

The effect of insoluble surfactant on the breakup of a fluid jet surrounded by another viscous fluid at low Reynolds number is studied both theoretically and experimentally. Equations governing the evolution of the interface and surfactant concentration are derived using a long wavelength approximation for the case of an inviscid jet and a slightly viscous jet surrounded by a more viscous fluid. These one dimensional partial differential equations governing the evolution of the slender jet are solved numerically for given initial interfacial perturbations and surfactant concentration. It is found that the presence of insoluble surfactant at the interface retards the …

Mechanics Of Biocell Landfill Settlements, Chamil Hiroshan Hettiarachchi

Dissertations

Prediction of landfill gas generation and settlements are of concerns in design and maintenance of biocell landfills. Accurate settlement prediction is essential for design of piping systems used for the delivery of re-circulated leachate and recovery of landfill gas. Landfill settlement is the result of change in overburden stresses and biodegradation of waste. Biodegradation-induced settlement results from the re-arrangement of waste skeleton in response to the decomposition of waste mass.

Current practice of landfill settlement modeling is predominantly empirical, thus most of the available techniques make no attempt to simulate the real mechanisms of waste settlement. Traditionally compressibility index is …

Evaporating Cross Flow Spray Jets In Gas-Solid Circulating Fluidized Bed, Tong Hoon Lee

Dissertations

Three-phase flow of solid-gas suspension with liquid spray is found in many industrial applications, including fluidized catalytic cracking in petroleum refinery process, and wet scrubbing process. This dissertation study is aimed to understand the gas-solid-liquid three-phase flow structure, phase interactions and transport in a gas-solid circulating fluidized bed where an evaporating cross-flow liquid spray jet from a rectangular nozzle with a fan angle is injected. The investigation is based on both numerical and experimental approaches. The numerical study is for detailed field descriptions of the flow structure, phase interaction and distributions whereas the experimental study is for simulation validations. The …

Dynamics Of Filaments, Flares And Coronal Mass Ejections (Cmes), Ju Jing

Dissertations

The objective of this dissertation is to investigate the connection between the dynamics of solar surface phenomena such as filament eruptions, flares, the coronal mass ejections (CMEs), the core of so-called solar activity, and the properties of the associated magnetic field for the development of forecasts of solar activity and space weather. Both statistical and case studies have been carried out.

The topics covered in this dissertation are: the statistical relationship among phenomena of solar activity, in particular, filament eruptions, flares and coronal mass ejections (CMEs); the correlation between magnetic reconnection rate and flux rope acceleration of two-ribbon flares; the …

The Effects Of Digital Audio On Social Presence, Motivation And Perceived Learning In Asynchronous Learning Networks, Eunhee Kim

Dissertations

This study explores the possibilities of applying digital audio to the ALN environment, so that students can speak and listen rather than type and read. Two sets of 1x2 field experiments (text vs. digital audio) were conducted with two formats of digital audio -recorded voice messages and narrated Microsoft PowerPoint presentation - used in several NJIT courses conducted via ALN. The perceptions of communication media were measured from two different user perspectives: active use when the subjects created their assignments using prescribed communication media (audio or text) and passive use when the subjects viewed/listened to other students' work.

The perceptions …