Digital Commons Network^™

Study Of Propagation And Detection Methods Of Terahertz Radiation For Spectroscopy And Imaging, Aparajita Bandyopadhyay

Dissertations

The applications of terahertz (THz, 1 THz is 1012 cycles per second or 300 pm in wavelength) radiation are rapidly expanding. In particular, THz imaging is emerging as a powerful technique to spatially map a wide variety of objects with spectral features which are present for many materials in THz region. Objects buried within dielectric structures can also be imaged due to the transparency of most dielectrics in this regime. Unfortunately, the image quality in such applications is inherently influenced by the scattering introduced by the sample inhomogeneities and by the presence of barriers that reduces both the transmitted power …

Linear And Log-Linear Models Based On Generalized Inverse Sampling Scheme, Soumi Lahiri

Dissertations

This dissertation explores the development of novel statistical techniques and the applications in modeling rare events using generalized inverse sampling scheme. The Poisson model can be used for independent frequency count data. Also negative binomial and negative multinomial (NMn) models are applicable when there is only one rare category in the population. Here, a new model, based on generalized inverse sampling scheme, is introduced to study several rare events simultaneouly. The generalized inverse sampling scheme is used to study several rare categories of a population. Samples are drawn until a predetermined number of the total of the rare events occur. …

Advanced Methods In Automatic Modulation Classification For Emerging Technologies, Hong Li

Dissertations

Modulation classification (MC) is of large importance in both military and commercial communication applications. It is a challenging problem, especially in non-cooperative wireless environments, where channel fading and no prior knowledge on the incoming signal are major factors that deteriorate the reception performance. Although the average likelihood ratio test method can provide an optimal solution to the MC problem with unknown parameters, it suffers from high computational complexity and in some cases mathematical intractability. Instead, in this research, an array-based quasi-hybrid likelihood ratio test (qHLRT) algorithm is proposed, which depicts two major advantages. First, it is simple yet accurate enough …

Novel Characterization Of Materials Using Thz Spectroscopic Techniques, Amartya Sengupta

Dissertations

Significant scientific and technical challenges within the terahertz (THz) frequency regime have recently motivated an array of new research activities. This involves numerous applications of this region of the electromagnetic spectrum between approximately 100 GHz (3mm) and 3 THz (100 µm) for both spectroscopy and imaging purposes. THz time domain spectroscopy is unique in that the time domain waveforms are measured and the complex optical constants are deduced directly without resorting to the Kramers-Kronig Analysis.

In this work, THz spectroscopy has been used to characterize different types of materials. Materials investigated consisted of semiconductors, gate dielectric materials, high energetic materials …

Mathematical Problems Arising In Interfacial Electrohydrodynamics, Dmitri Tseluiko

Dissertations

In this work we consider the nonlinear stability of thin films in the presence of electric fields. We study a perfectly conducting thin film flow down an inclined plane in the presence of an electric field which is uniform in its undisturbed state, and normal to the plate at infinity. In addition, the effect of normal electric fields on films lying above, or hanging from, horizontal substrates is considered. Systematic asymptotic expansions are used to derive fully nonlinear long wave model equations for the scaled interface motion and corresponding flow fields. For the case of an inclined plane, higher order …

Facial Analysis In Video : Detection And Recognition, Peichung Shih

Dissertations

Biometric authentication systems automatically identify or verify individuals using physiological (e.g., face, fingerprint, hand geometry, retina scan) or behavioral (e.g., speaking pattern, signature, keystroke dynamics) characteristics. Among these biometrics, facial patterns have the major advantage of being the least intrusive. Automatic face recognition systems thus have great potential in a wide spectrum of application areas. Focusing on facial analysis, this dissertation presents a face detection method and numerous feature extraction methods for face recognition.

Concerning face detection, a video-based frontal face detection method has been developed using motion analysis and color information to derive field of interests, and distribution-based distance …

Interactions Of Ionic Liquids With Uranium And Its Implications On Biotransformation, Chengdong Zhang

Dissertations

Room temperature ionic liquids (ILs) are pure ionic compounds with melting points below 100°C, which have drawn great attention due to their many unique properties. They have been widely used in organic synthesis, analytical chemistry, and biochemistry. Although ionic liquids have been used to extract metals and radionuclides, there is no systematic study on the interactions of ILs with uranium and their effects on the biotransformation of uranium.

My research focused on: (1) the interactions between uranium and ionic liquids in aqueous solution; and (2) biotransformation of uranium in the presence of ILs. The interactions between three representative ionic liquids, …

Enhancing Web Marketing By Using Ontology, Xuan Zhou

Dissertations

The existence of the Web has a major impact on people's life styles. Online shopping, online banking, email, instant messenger services, search engines and bulletin boards have gradually become parts of our daily life. All kinds of information can be found on the Web. Web marketing is one of the ways to make use of online information. By extracting demographic information and interest information from the Web, marketing knowledge can be augmented by applying data mining algorithms. Therefore, this knowledge which connects customers to products can be used for marketing purposes and for targeting existing and potential customers. The Web …

Structural Auditing Methodologies For Controlled Terminologies, Hua Min

Dissertations

Several auditing methodologies for large controlled terminologies are developed. These are applied to the Unified Medical Language System XXXX and the National Cancer Institute Thesaurus (NCIT). Structural auditing methodologies are based on the structural aspects such as IS-A hierarchy relationships groups of concepts assigned to semantic types and groups of relationships defined for concepts. Structurally uniform groups of concepts tend to be semantically uniform. Structural auditing methodologies focus on concepts with unlikely or rare configuration. These concepts have a high likelihood for errors.

One of the methodologies is based on comparing hierarchical relationships between the META and SN, two major …

Gas Chromatography On Self Assembled Single Walled Carbon Nanotubes, Mahesh Kumar Karwa

Dissertations

Carbon nanotubes (CNTs) are nano-sized carbon-based sorbents, which have high surface area, large aspect ratio, can be self-assembled and are known to be stable at high temperatures. It is therefore conceivable that separation techniques, such as, gas chromatography (GC) can benefit from their unique properties and nano-scale interactions. Self-assembly, in-contrast to packing these materials in a tube, prevents them from agglomeration and thus facilitates in retaining their nano-characteristics. In this research, novel substrates, such as, steel tubings, on a scaled-up level have been explored for the self-assembly process of CNTs, for applications such as gas chromatography, where the CNTs served …

Applications Of Room Temperature Ionic Liquids In Interfacial Polymerization, Lining Zhu

Dissertations

Room temperature ionic liquids (ILs), with their unique physical and chemical properties, have been of great interest in various areas of chemical science and engineering during the last decade. In this dissertation, polyurea and polyamide films with surface nanostructures were synthesized by interfacial polymerization (IP) with ILs without stirring. Both polymers were prepared at the interface between n-hexane and a series of 1 -alkyl-3-methylimidazolium ILs.

Nanoporous or nanofibrous polymer morphologies with various sizes ranging from 50 to 500 nm and geometries, depending on the ILs used, were observed by scanning electron microscopy (SEM). A correlation length of ~20nm and a …

Medium Access Control Design For All-Ip And Ad Hoc Wireless Network, Zaihan Jiang

Dissertations

Medium Access Control (MAC) protocol in a wireless network controls the access of wireless medium by mobile terminals, in order to achieve its fair and efficient sharing. It plays an important role in resource management and QoS support for applications. All-IP wireless WAN is fully IP protocol-based and it is a strong candidate beyond 3G (Third Generation Wireless Network). Ad hoc wireless network has recently been the topic of extensive research due to its ability to work properly without fixed infrastructure.

This dissertation is composed of two main parts. The first part pursues a Prioritized Parallel Transmission MAC (PPTM) design …

The Relationship Between Resource Allocation Patterns In Missouri K-12 Public School Districts And Student Performance, Aaron Ross Butler

Dissertations

The link between school funding and student achievement has been a topic of debate for many years. School leaders and policy makers have sought ways to increase student achievement while using educational funding in an efficient manner. Previous initiatives to examine the relationship between funding and achievement have included education production functions, standards-based reforms, reallocation of resources, and minimum funding levels. This study was designed to examine the relationship between resource allocation patterns and student achievement in 447 Missouri K-12 public schools. The relationship between school districts¿ resources and their achievement on the 10th grade mathematics and 11th grade communication …

How Teacher Attitudes And Administrator Behaviors Affect Levels Of Technology Integration In The Classroom, Sheri Leigh Bradshaw

Dissertations

Multiple linear regression analysis was conducted to evaluate how well teachers’ attitudes predict levels of technology integration into the classroom. This study also investigated whether perceived support from the administrator as the instructional leader was related to teachers’ levels of technology integration into the classroom. The population for this study included identified school districts in rural North Georgia. Utilizing the National Center for Education Statistics (NCES) for the 2002-2003 school year, the researcher identified 5 peer districts: Franklin County, Gilmer County, Stephens County, Union County, and White County. All middle and high school teachers within a district were invited to …

Afterschool Intervention Programs’ Impact Upon Select Variables Among 10th Grade Students In The Education Longitudinal Stu D Y (Els) 2002 Dataset, Diane Jackson-Chapman

Dissertations

This researcher analyzed data from the database of the National Center for Educational Statistics: Education Longitudinal Studies (ELS) 2002. The study included responses from 743 principals in 752 schools and from 15,362 10th grade students from public, Catholic, and other private schools. The dissertation investigated if the percentage of school participation in afterschool/summer outreach programs could predict students’ perceptions of teachers, drug availability on campus, student misbehaviors and punishments, and attitudes toward school and grades. The independent variable was the percentage of students in afterschool/summer outreach programs as reported by principals. The dependent variables related to students’ responses to attitudes …

School Web Sites And Teacher Employment Interest, David Theodore Freeman

Dissertations

The Internet has changed the way many organizations, including public and private schools, recruit and select employees. It has also changed the way many people research and pursue employment opportunities, including those seeking positions in education. The school Web site is often the medium of first contact between a school or school district and a potential employee. That first contact can influence the potential employee’s decision to actively pursue employment with a school or a school district.

This research measured the reactions o f preservice teachers who visited three grade-level appropriate school Web sites of “poor,” “average,” and “best” distinction. …

Acts 2:42 In 2006: Examining Small Group Discussion In An American Mega-Church, Sheri Guseman Edd

Dissertations

During the last century, Americans have become increasingly isolated from one another, resulting in feelings of loneliness and creating a void of community (Frazee, 2001). However, as attendance at mainline churches continues to decline (Stafford, 1998), attendance and participation in mega-churches, defined as those serving more than 2,500 individuals and offering a multiplicity of services, continues to increase (http://www.hirr.hartsem.edu/org ). One popular explanation for this phenomenon is that mega-churches are often characterized by an organized small group ministry---something absent in more traditional churches. Although this trend has clearly swept the nation (Gladwell, 2005), related research on the efficacy of the …

The Effects Of Participating In Youth Theater, Mark Plato Arapostathis Edd

Dissertations

The purpose of this study is to explore the effects of student participation in youth theater on the students. Research suggests that theater arts have aided in building student cognition and contributed to the development of literacy. Davenport (1999) concluded that the experience and knowledge that one gains from theater arts form the basic building blocks for the skills needed to learn and to become literate. He added that creative expression is the actual production of a work of art, and this direct, personal involvement provides the experience base upon which cognitive development occurs. This cognitive development has practical application …

Investigations Of Poly[(Styrene-Co-P-Methylstyrene)-Risobutylene- R-(Styrene-Co-P-Methylstyrene)] And Poly[(Acrylic Acid)-5-Styrene-Jb-Is0butylene-5-Styrene-Jb-(Acrylic Acid)], James Grabill Kopchick

Dissertations

The pMe study was conducted to understand the morphological and physical property changes that occur as the ratio of pMe to styrene is increased, effectively increasing the aliphatic units. By the introduction of pMe, the interface region becomes more blended/compatible as the pMe migrates to the interface. These pMe groups are theorized in effect to create multiple ‘anchors’ to distribute the loads experienced at the interface more effectively creating a synergistic effect on the final properties of the copolymers. The primary goals of the pentablock study were the characterization of unique membranes as related to …

The Total And Specific Dimensions Of Self Concept Related To Female Participation In Collegiate Athletics, Dane Bradford Beary

Dissertations

The purpose of this study was to determine if differences existed between female collegiate sport participation and non-participation, as well as female collegiate individual and team sport participation on the total, the specific dimensions of self-concept and supplementary scores as rendered by the Tennessee Self-Concept Scale Second Edition TSCS:2 (Fitts & Warren, 1996). A subject pool of N=190 participants were used. All subjects included in data analysis were female undergraduate students. A multivariate analysis of variance (M ANOVA) was utilized to evaluate effects of sports participation versus non-participation and individual versus team sports participation on self-concept. On sports participation versus …

A Conductor’S Guide To Wind Instrument Deficiencies: A Practical Addendum To The Undergraduate Conducting Text, Donald Bradley Snow

Dissertations

commonly used undergraduate conducting texts that teach the correction of wind intonation deficiencies. Research has indicated that conductors must be aware of and be trained to recognize and correct intonation deficiencies of wind instruments. Music teachers must understand acoustical differences among just, Pythagorean, and tempered tuning systems. Nonetheless, existing pedagogical materials for undergraduate conductors in training are of little or no help. The supplemental text addresses intonation deficiencies and provides musical examples and exercises to help the young conductor gain an understanding of the factors that adversely affect the intonation of wind instruments. The body of literature on the subject …

Nilpotent Orbits On Infinitesimal Symmetric Spaces, Joseph A. Fox

Dissertations

Let G be a reductive linear algebraic group defined over an algebraically closed field k whose characteristic is good for G. Let [straight theta] be an involution defined on G, and let K be the subgroup of G consisting of elements fixed by [straight theta]. The differential of [straight theta], also denoted [straight theta], is an involution of the Lie algebra [Special characters omitted.] = Lie (G ), and it decomposes [Special characters omitted.] into +1- and -1-eigenspaces, [Special characters omitted.] and [Special characters omitted.] , respectively. The space [Special characters omitted.] identifies with the tangent space at the …

Synthetic Studies Of 1,10-Phenanthroline Derivatives As Novel Catalysis Ligands And Their Application In Transition Metals Catalyzed Reactions, Son Duc Tran

Dissertations

The preparation of 1,10-phenanthroline derivatives entailed ring opening reactions of 1,10-phenanthroline epoxide as a key transformation, affording novelbidentate nitrogen ligands with new stereogenic centers in the 5- and 6-position. This research was concerned with (i) the epoxidation of 1,10-phen, (ii) epoxide ring opening reactions, (iii) the formation of trans -5,6-disubstituted-1,10-phenanthroline metal complexes, and (iv) application of 1,10-phenanthroline derivatives in metal-catalyze reactions such as palladium-catalyzed allylic substitution and aminohalogenation reactions; Zinc-catalyzed direct aldolreaction, and acetophenone reduction; Nickel-catalyzed Michael addition reaction.

New Estimators Of A Circular Median, Sauwanit Ratanaruamkarn

Dissertations

The specific properties of probability distributions on a circle require different definitions of several statistical concepts. For example, a median that can always be found for linear data not always exists on the circle. Several estimators of a circular median were proposed, lately by Otieno (2002), Otieno and Anderson - Cook (2003). Their work is, however, focused on the "preferred direction" which coincides with the median, mean and mode in the case of symmetric, unimodal distributions. This dissertation is focused on the estimators of a population median in a wider range of population distributions on a circle including distributions with …

Localization In Wireless Sensor Networks, Mark Terwilliger

Dissertations

With the proliferation of wireless sensor networks, providing location-aware technology and services to new applications have become important for developers. Localization is the problem of determining the positions of nodes in an ad hoc network. With the constrained resources of network sensors, providing robust localization services remains a fundamental research challenge facing the entire sensor network development community.

The initial localization problem that we addressed was to design and develop a working system that could locate equipment, such as a laptop or video projector. Ferret, the localization system developed, uses two different ranging techniques to help locate an object to …

Testing Procedures For Group Sequential Clinical Trials With Multiple Survival Endpoints, Rebecca C. Scherzer

Dissertations

This research gives methods for sequential monitoring of survival data in clinical trials with multiple endpoints. We illustrate the use of marginal proportional hazards models and other survival models with various group sequential methods to test multiple survival endpoints at K interim analyses. To adjust for multiplicity at each interim analysis, we consider and extend methods developed by Tang and Geller (1999), Follmann, et al. (1994), and others. These methods are motivated, compared, and evaluated using survival data from a clinical study and using simulation studies.

A Study On Perceptions Of Civil Engineers Regarding Mandatory Continuing Education, Alee A. Sleymann

Dissertations

This study explored the perceptions of civil engineers regarding continuing professional competency requirements for license renewal. In this study,continuing professional competency is assumed to have a direct relationship to public welfare and safety. The policy of mandatory continuing education was adopted primarily for this reason. Currently, mandatory continuing education is adopted by 29 states as the method of assuring continued professional competency.

Many professionals, however, have not welcomed this mandatory continuing education (MCE) policy. The reason for this opposition is the claimed ineffectiveness of this policy in fostering continued competency. In addition, the regulatory boards and policy advocates have not …

Text Mining With Exploitation Of User's Background Knowledge : Discovering Novel Association Rules From Text, Xin Chen

Dissertations

The goal of text mining is to find interesting and non-trivial patterns or knowledge from unstructured documents. Both objective and subjective measures have been proposed in the literature to evaluate the interestingness of discovered patterns. However, objective measures alone are insufficient because such measures do not consider knowledge and interests of the users. Subjective measures require explicit input of user expectations which is difficult or even impossible to obtain in text mining environments.

This study proposes a user-oriented text-mining framework and applies it to the problem of discovering novel association rules from documents. The developed system, uMining, consists of two …

Facial Feature Representation And Recognition, Chao-Fa Chuang

Dissertations

Facial expression provides an important behavioral measure for studies of emotion, cognitive processes, and social interaction. Facial expression representation and recognition have become a promising research area during recent years. Its applications include human-computer interfaces, human emotion analysis, and medical care and cure.

In this dissertation, the fundamental techniques will be first reviewed, and the developments of the novel algorithms and theorems will be presented later. The objective of the proposed algorithm is to provide a reliable, fast, and integrated procedure to recognize either seven prototypical, emotion-specified expressions (e.g., happy, neutral, angry, disgust, fear, sad, and surprise in JAFFE database) …

Probabilistic Approaches To The Design Of Wireless Ad Hoc And Sensor Networks, Zhen Guo

Dissertations

The emerging wireless technologies has made ubiquitous wireless access a reality and enabled wireless systems to support a large variety of applications. Since the wireless self-configuring networks do not require infrastructure and promise greater flexibility and better coverage, wireless ad hoc and sensor networks have been under intensive research. It is believed that wireless ad hoc and sensor networks can become as important as the Internet. Just as the Internet allows access to digital information anywhere, ad hoc and sensor networks will provide remote interaction with the physical world.

Dynamics of the object distribution is one of the most important …