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Indoor Air Quality: Determination Of Voc's In A Reproductive Clinic., Miriam Rachel Trivette Dec 2006

Indoor Air Quality: Determination Of Voc's In A Reproductive Clinic., Miriam Rachel Trivette

Electronic Theses and Dissertations

The purpose of this study was to perform an indoor air quality (IAQ) investigation at the Center for Applied Reproductive Science (CARS) to assess whether VOCs exist at levels dangerous to embryo. Formaldehyde, n-hexane, benzene, and styrene concentrations were measured at six locations. Formaldehyde concentrations were comparable to office and residential indoor air. N-hexane, benzene, and styrene were not detected. In addition, acetaldehyde, ethanol, and isopropyl alcohol were detected. IAQ parameters (carbon dioxide, temperature, humidity, pressure, and particulates) were measured at 22 sites monthly for one year. Temperature and humidity readings were within Environmental Protection Agency recommendations. Particulate concentrations were …


Surface Modification Of Pigments And Its Role In Offset Ink Setting, Wei Gu Dec 2006

Surface Modification Of Pigments And Its Role In Offset Ink Setting, Wei Gu

Electronic Theses and Dissertations

Ink setting affects offset print quality issues such as print mottle and print gloss. It is known that ink setting depends on many factors, such as the nature of the substrate, the properties of the coating, and the ink formulation. However, the role of pigment surface chemistry in offset ink setting is unknown. From an experimental perspective, it is difficult to determine the role of the surface chemistry as it requires paper coatings that are similar in physical properties and differ only in the pigment surface chemistry. The aim of this study was two-fold. The first was to apply methods …


Yellow Tree: A Distributed Main-Memory Spatial Index Structure For Moving Objects, Hariharan Gowrisankar Dec 2006

Yellow Tree: A Distributed Main-Memory Spatial Index Structure For Moving Objects, Hariharan Gowrisankar

Electronic Theses and Dissertations

Mobile devices equipped with wireless technologies to communicate and positioning systems to locate objects of interest are common place today, providing the impetus to develop location-aware applications. At the heart of location-aware applications are moving objects or objects that continuously change location over time, such as cars in transportation networks or pedestrians or postal packages. Location-aware applications tend to support the tracking of very large numbers of such moving objects as well as many users that are interested in finding out about the locations of other moving objects. Such location-aware applications rely on support from database management systems to model, …


Production Of Ethanol From Hardwood, Jay Mitchell Dec 2006

Production Of Ethanol From Hardwood, Jay Mitchell

Electronic Theses and Dissertations

Diminishing crude oil and natural gas supplies, along with concern about greenhouse gas are major driving forces in the search for efficient renewable energy sources. The conversion of lignocellulosic biomass to energy and useful chemicals is a component of the solution. Ethanol is most commonly produced by enzymatic hydrolysis of complex carbohydrates to simple sugars followed by fermentation using yeast.

C6Hl0O5 + H2O −Enxymes→ C6H12O6 −Yeast→ 2CH3CH2OH + 2C02

In the U.S. corn is the primary starting raw material for commercial ethanol production. …


Determining Environmental Drivers Of Fish Community Structure Along The Coast Of Maine, Adrian Jordaan Dec 2006

Determining Environmental Drivers Of Fish Community Structure Along The Coast Of Maine, Adrian Jordaan

Electronic Theses and Dissertations

The work presented here was conceived to determine whether structure in marine communities could be related to multiple scaled environmental parameters, as seen in lake and stream systems. Four datasets collected from 2001 to 2005 were used. The datasets ranged from local scale tidepool and estuarine surveys, to more regional intertidal/subtidal surveys and conclude using a coast-wide trawl survey. Initially, a bootstrap program for running principal component analysis (PCA) was developed and tested for utility with additional information from Pearson correlation coefficients. The bootstrap-PC A program was capable of determining confidence limits for correlations amongst species. The results from analysis …


Diel And Tidal Rhythms Of Emercenge Events Based On Acousitc Observations In A Shallow Estuary, Mei Sato Dec 2006

Diel And Tidal Rhythms Of Emercenge Events Based On Acousitc Observations In A Shallow Estuary, Mei Sato

Electronic Theses and Dissertations

Field observations of emergence events by epibenthic animals were conducted with two Tracor Acoustic Profiling Systems (TAPS) in the Damariscotta River estuary, Maine, in fall 2005 and summer 2006. Spectral analysis revealed that periodic temporal variability of the acoustic signals was concentrated at four periods. One was the solar day (24 h) and the other three were lunar tidal periods of 25.82 (diurnal or Oi), 12.42 (semidiurnal or M2) and 6.21 h (half the semidiurnal period). The mysid Neomysis americana showed strong nocturnal migration patterns of water-column activity during its peak summer emergence season, regulated by the diel cycle. Toward …


A Complete Characterization Of Maximal Symmetric Difference-Free Families On {1,…N}., Travis Gerarde Buck Aug 2006

A Complete Characterization Of Maximal Symmetric Difference-Free Families On {1,…N}., Travis Gerarde Buck

Electronic Theses and Dissertations

Prior work in the field of set theory has looked at the properties of union-free families. This thesis investigates families based on a different set operation, the symmetricc difference. It provides a complete characterization of maximal symmetric differencefree families of subsets of {1, . . . n}


Comparing The Statistical Tests For Homogeneity Of Variances., Zhiqiang Mu Aug 2006

Comparing The Statistical Tests For Homogeneity Of Variances., Zhiqiang Mu

Electronic Theses and Dissertations

Testing the homogeneity of variances is an important problem in many applications since statistical methods of frequent use, such as ANOVA, assume equal variances for two or more groups of data. However, testing the equality of variances is a difficult problem due to the fact that many of the tests are not robust against non-normality. It is known that the kurtosis of the distribution of the source data can affect the performance of the tests for variance. We review the classical tests and their latest, more robust modifications, some other tests that have recently appeared in the literature, and use …


Reversed-Phase Hplc Determination Of Citral In Locally Grown Lemon Grass Harvested At Different Season., Mahmoud Al-Shaer Aug 2006

Reversed-Phase Hplc Determination Of Citral In Locally Grown Lemon Grass Harvested At Different Season., Mahmoud Al-Shaer

Electronic Theses and Dissertations

A simple HPLC procedure for the quantitative determination of citral, the major fragrant component in the lemon grass, has been developed. The procedure involves a C-8 stationary phase using a 90:10 methanol: water pH 5 mobile phase containing 0.25% 1-octanesulfonic acid and an UV detector (set at 233 nm). The lemon grass leaves were harvested fresh at different times of the year and were soaked in methanol for 48 hours without any mechanical assistance to extract the citral and other methanol soluble components. The method showed good reproducibility with relative standard deviation of 2.8% and 10.8% for two different sets …


Amended Estimators Of Several Ratios For Categorical Data., Dandan Chen Aug 2006

Amended Estimators Of Several Ratios For Categorical Data., Dandan Chen

Electronic Theses and Dissertations

Point estimation of several association parameters in categorical data are presented. Typically, a constant is added to the frequency counts before the association measure is computed. We will study the accuracy of these adjusted point estimators based on frequentist and Bayesian methods respectively. In particular, amended estimators for the ratio of independent Poisson rates, relative risk, odds ratio, and the ratio of marginal binomial proportions will be examined in terms of bias and mean squared error.


Polyaniline And Its Derivatives For Environmental Analysis., Atogho Jude Abia Aug 2006

Polyaniline And Its Derivatives For Environmental Analysis., Atogho Jude Abia

Electronic Theses and Dissertations

Electrooxidation has been used to deposit thin film polyaniline as well as its derivative - thin film poly (ortho-phenylenediamine) (POPD) and poly (meta-phenylenediamine) (PMPD) on carbon electrodes, which are subsequently used to monitor the environmental heavy metal ions (Hg2+, Pb2+ ,Cd2+) through a rather unusual "blocking" of anodic stripping for these metals. Using Hg2+ as a model, its cyclic voltammogram for a modified glassy carbon electrode with the resultant polymer shows an enhanced cathodic peak that increases linearly with the analyte ion concentration. POPD also exhibits unique selective detection for organic species. Acetaminophen and …


Determination Of Cholesterol In Foods By Flow Injection Analysis With Perroxyoxalate Chemiluminescence., Abisake Feleke Aug 2006

Determination Of Cholesterol In Foods By Flow Injection Analysis With Perroxyoxalate Chemiluminescence., Abisake Feleke

Electronic Theses and Dissertations

Cholesterol is an important biological molecule with many important functions. However, high serum cholesterol is a health hazard. Thus analysis of cholesterol is important and many analytical techniques have been developed. The objectives of the proposed research are to develop an economical, rapid method for the determination of total cholesterol with good selectivity and enhanced sensitivity. For evaluation of proposed flow injection analysis with peroxyoxalate chemiluminescence (FIA-POCL) method, figures of merit such as accuracy, precision, and linear dynamic range will be assessed. The proposed procedure was then applied to the determination of total cholesterol in foods. The procedure was linear …


Personal Privacy Protection Within Pervasive Rfid Environments, Eeva Kaarina Hedefine Aug 2006

Personal Privacy Protection Within Pervasive Rfid Environments, Eeva Kaarina Hedefine

Electronic Theses and Dissertations

Recent advancements in location tracking technologies have increased the threat to an individual's personal privacy. Radio frequency identification (RFID) technology allows for the identification and potentially continuous tracking of an object or individual, without obtaining the individual's consent or even awareness that the tracking is taking place. Although many positive applications for RFID technology exist, for example in the commercial sector and law enforcement, the potential for abuse in the collection and use of personal information through this technology also exists. Location data linked to other types of personal information allows not only the detection of past spatial travel and …


Semantic Similarity Of Spatial Scenes, Konstantinos A. Nedas Aug 2006

Semantic Similarity Of Spatial Scenes, Konstantinos A. Nedas

Electronic Theses and Dissertations

The formalization of similarity in spatial information systems can unleash their functionality and contribute technology not only useful, but also desirable by broad groups of users. As a paradigm for information retrieval, similarity supersedes tedious querying techniques and unveils novel ways for user-system interaction by naturally supporting modalities such as speech and sketching. As a tool within the scope of a broader objective, it can facilitate such diverse tasks as data integration, landmark determination, and prediction making. This potential motivated the development of several similarity models within the geospatial and computer science communities. Despite the merit of these studies, their …


Modeling Large Whale Entanglement Injuries: An Experimental Analysis Of The Influence Of Tissue Compliance, Line Tension, And Draw-Length On Epidermal Abrasion Resistance, Jeremy Paul Winn Aug 2006

Modeling Large Whale Entanglement Injuries: An Experimental Analysis Of The Influence Of Tissue Compliance, Line Tension, And Draw-Length On Epidermal Abrasion Resistance, Jeremy Paul Winn

Electronic Theses and Dissertations

Two test systems were developed to evaluate the influence of draw-length and tissue compliance on entanglement-induced epidermal abrasion in humpback (Megaptera novaeangliae) and right whale (Eubalaena glacialis) tissue samples. Under straight pull abrasion tests an adult right whale fluke required 3.7 times the load and 15 times the draw-length of a right whale calf flipper to induce epidermal failure while a humpback fluke was intermediate between these extremes. Epidermal thickness did not appear to be the cause of this difference in abrasion resistance. Epidermal thickness averaged 8.0k0.2 mm for the calf flipper, 4.9k0.4 rnrn for the humpback fluke, and 5.1k0.1 …


Bayesian Reference Inference On The Ratio Of Poisson Rates., Changbin Guo May 2006

Bayesian Reference Inference On The Ratio Of Poisson Rates., Changbin Guo

Electronic Theses and Dissertations

Bayesian reference analysis is a method of determining the prior under the Bayesian paradigm. It incorporates as little information as possible from the experiment. Estimation of the ratio of two independent Poisson rates is a common practical problem. In this thesis, the method of reference analysis is applied to derive the posterior distribution of the ratio of two independent Poisson rates, and then to construct point and interval estimates based on the reference posterior. In addition, the Frequentist coverage property of HPD intervals is verified through simulation.


On The Chromatic Number Of The Ao(2, K , K-1) Graphs., Navya Arora May 2006

On The Chromatic Number Of The Ao(2, K , K-1) Graphs., Navya Arora

Electronic Theses and Dissertations

The alphabet overlap graph is a modification of the well known de Bruijn graph. De Bruijn graphs have been highly studied and hence many properties of these graphs have been determined. However, very little is known about alphabet overlap graphs. In this work we determine the chromatic number for a special case of these graphs.

We define the alphabet overlap graph by G = AO(a, k, t, where a, k and t are positive integers such that 0 ≤ tk. The vertex set of G is the set of all k …


Strategies For Encoding Xml Documents In Relational Databases: Comparisons And Contrasts., Jonathan Lee Leonard May 2006

Strategies For Encoding Xml Documents In Relational Databases: Comparisons And Contrasts., Jonathan Lee Leonard

Electronic Theses and Dissertations

The rise of XML as a de facto standard for document and data exchange has created a need to store and query XML documents in relational databases, today's de facto standard for data storage. Two common strategies for storing XML documents in relational databases, a process known as document shredding, are Interval encoding and ORDPATH Encoding. Interval encoding, which uses a fixed mapping for shredding XML documents, tends to favor selection queries, at a potential cost of O(N) for supporting insertion queries. ORDPATH Encoding, which uses a looser mapping for shredding XML, supports fixed-cost insertions, at a potential cost of …


Double Domination Edge Critical Graphs., Derrick Wayne Thacker May 2006

Double Domination Edge Critical Graphs., Derrick Wayne Thacker

Electronic Theses and Dissertations

In a graph G=(V,E), a subset SV is a double dominating set if every vertex in V is dominated at least twice. The minimum cardinality of a double dominating set of G is the double domination number. A graph G is double domination edge critical if for any edge uvE(), the double domination number of G+uv is less than the double domination number of G. We investigate properties of double domination edge critical graphs. In particular, we characterize the double domination edge critical trees and …


An Analysis Of Financial Planning For Employees Of East Tennessee State University., Steven Roy Campbell May 2006

An Analysis Of Financial Planning For Employees Of East Tennessee State University., Steven Roy Campbell

Electronic Theses and Dissertations

The purpose of this study was to determine if East Tennessee State University provides its employees appropriate financial planning services. In particular, it is unknown to what degree employees of East Tennessee State University have actively engaged in financial planning.

The research was conducted during June and July, 2005. Data were gathered by surveying faculty, staff, and retirees of the university. Ten percent of the population responded to the study. The survey instrument covered the areas of retirement, other financial planning services, and attitudes toward financial planning.

The results of the data analysis gave insight into what degree employees of …


Fluctuating Asymmetry And Its Relationship To Established Indicators Of Environmental Stress., Matthew Stephen Shotwell May 2006

Fluctuating Asymmetry And Its Relationship To Established Indicators Of Environmental Stress., Matthew Stephen Shotwell

Electronic Theses and Dissertations

Fluctuating asymmetry (FA) is commonly thought to be a predictor of environmental stress. However, the relationship between FA and established indicators for environmental stress has received little attention. In this study, 10-38 specimens of the freshwater fish Rhinichthys atratulus were collected from 15 natural populations under varying amounts of environmental stress. Asymmetry measurements in three bilateral characters of the specimens were used to investigate the relationship between FA and established indicators of environmental stress. Significant differences in the magnitude of FA were observed between sampling locations. However, the relationship between estimates of FA and established indicators produced varying results. The …


Trees With Unique Minimum Locating-Dominating Sets., Stephen M. Lane May 2006

Trees With Unique Minimum Locating-Dominating Sets., Stephen M. Lane

Electronic Theses and Dissertations

A set S of vertices in a graph G = (V, E) is a locating-dominating set if S is a dominating set of G, and every pair of distinct vertices {u, v} in V - S is located with respect to S, that is, if the set of neighbors of u that are in S is not equal to the set of neighbors of v that are in S. We give a construction of trees that have unique minimum locating-dominating sets.


Investigating How Students Think About And Learn Quantum Physics: An Example From Tunneling, Jeffrey Todd Morgan May 2006

Investigating How Students Think About And Learn Quantum Physics: An Example From Tunneling, Jeffrey Todd Morgan

Electronic Theses and Dissertations

Much of physics education research (PER) has focused on introductory courses and topics, with less research done into how students learn physics in advanced courses. Members of The University of Maine Physics Education Research Laboratory (PERL) have begun studying how students in advanced physics courses reason about classical mechanics, thermal physics, and quantum physics. Here, we describe an investigation into how students reason about quantum mechanical tunneling, and detail how those findings informed a portion of a curriculum development project. Quantum mechanical tunneling is a standard topic discussed in most modern physics and quantum physics courses. Understanding tunneling is crucial …


Object Tracking In Distributed Video Networks Using Multi-Dimentional Signatures, Sabeshan Srinivasan May 2006

Object Tracking In Distributed Video Networks Using Multi-Dimentional Signatures, Sabeshan Srinivasan

Electronic Theses and Dissertations

From being an expensive toy in the hands of governmental agencies, computers have evolved a long way from the huge vacuum tube-based machines to today's small but more than thousand times powerful personal computers. Computers have long been investigated as the foundation for an artificial vision system. The computer vision discipline has seen a rapid development over the past few decades from rudimentary motion detection systems to complex modekbased object motion analyzing algorithms. Our work is one such improvement over previous algorithms developed for the purpose of object motion analysis in video feeds. Our work is based on the principle …


Near-Infrared Observations Of Comet-Asteroid Transition Objects, Julie Elaine Ziffer Jan 2006

Near-Infrared Observations Of Comet-Asteroid Transition Objects, Julie Elaine Ziffer

Electronic Theses and Dissertations

The primary objective of this research is to characterize the surface composition of five comet-asteroid transition objects via near-infrared spectroscopy. The five targets include two asteroids with Tisserand invariants lower than 3.0 (1373 Cincinnati and 2906 Caltech), one asteroid that is likely an extinct comet (944 Hidalgo), one intermittent activity comet (162P/Siding Spring), and one nearly dormant comet (28P/Neujmin1). Previous research regarding cometary end states and dynamical and physical properties of comets and asteroids provides the foundation for this work. Focusing primarily on the 1-2.5 µm spectral region of the five target objects, this project specifically searches for mineral species …


Sources And Deposition Processes Linking Atmospheric Chemistry And Firn Records From Four Glacier Accumulation Zones In The Mcmurdo Dry Valleys, Antarctica, Bruce R. Williamson Jan 2006

Sources And Deposition Processes Linking Atmospheric Chemistry And Firn Records From Four Glacier Accumulation Zones In The Mcmurdo Dry Valleys, Antarctica, Bruce R. Williamson

Electronic Theses and Dissertations

Samples of snow and firn from accumulation zones on the Victoria Upper Glacier, the Clark Glacier, the Commonwealth Glacier and the Blue Glacier in the McMurdo Dry Valleys (~77 to 78º S and 161 to 164º E), Antarctica, are evaluated chemically and isotopically to determine the relative importance of local (site-specific) factors versus regional-scale climatic influences in defining regional glaciochemistry. Two approaches for distinguishing these controls are examined: comparing chemical concentrations using multivariate statistical analysis, and examining the effect of physical filtration (capturing particulate material largely originating in close proximity to each site) on sample values. These techniques provide constraints …


Truly Non Invasive Glucose Optical Sensor Based On Metal Nanoparticles Generation, Marisol Garcia Jan 2006

Truly Non Invasive Glucose Optical Sensor Based On Metal Nanoparticles Generation, Marisol Garcia

Electronic Theses and Dissertations

Diabetes is a disease that causes many complications in human normal function. This disease represents the sixth-leading cause of death in USA. Prevention of diabetes-related complications can be accomplished through tight control of glucose levels in blood. In the last decades many different glucose sensors have been developed, however, none of them are really non invasive. Herein, we present the study of the application of gold and silver nanoparticles with different shapes and aspect ratios to detect glucose traces in human fluids such as tears and sweat. This is to our knowledge the first truly non invasive glucose optical sensor, …


Radiation Studies Of The Tin-Doped Microscopic Droplet Laser Plasma Light Source Specific To Euv Lithography, Chiew-Seng Koay Jan 2006

Radiation Studies Of The Tin-Doped Microscopic Droplet Laser Plasma Light Source Specific To Euv Lithography, Chiew-Seng Koay

Electronic Theses and Dissertations

Extreme ultraviolet lithography(EUVL) is being developed worldwide as the next generation technology to be inserted in ~ 2009 for the mass production of IC chips with feature sizes <35 nm. One major challenge to its implementation is the development of a 13.5 nm EUV source of radiation that meets the requirements of current roadmap designs of the source of illumination in commercial EUVL scanners. The light source must be debris-free, in a free-space environment with the imaging EUV optics that must provide sufficient, narrow spectral band EUV power to print 100 wafers/hr. To meet this need, extensive studies on emission from a laser plasma source utilizing tin-doped droplet target was conducted. Presented in this work, are the many optical techniques such as spectroscopy, radiometry, and imaging, that were employed to characterize and optimize emission from the laser plasma source State of the art EUV spectrographs were employed to observe the source's spectrum under various laser irradiation conditions. Comparing the experimental spectra to those from theory, has allowed the determination of the Sn ion stages responsible for emitting into the useful EUV bandwidth. Experimental results were compared to spectral simulations obtained using Collisional-Radiative Equilibrium (CRE) model, as well. Moreover, extensive measurements surveying source emission from 2 nm to 30 nm, which is the region of the electromagnetic spectrum defined as EUV, was accomplished. Absolutely calibrated metrology was employed with the Flying Circus instrument from which the source's conversion efficiency (CE)--from laser to the useful EUV energy--was characterized under various laser irradiation conditions. Hydrodynamic simulations of the plasma expansion together with the CRE model predicted the condition at which optimum conversion could be attained. The condition was demonstrated experimentally, with the highest CE to be slightly above 2%, which is the highest value among all EUV source contenders. In addition to laser intensity, the CE was found to depend on the laser wavelength. For better understanding, this observation is compared to results from simulations. Through a novel approach in imaging, the size of the plasma was characterized by recording images of the plasma within a narrow band, around 13.5 nm. The size, approximately 100 ìm, is safely within the etendue limit set by the optical elements in the EUV scanner. Finally, the notion of irradiating the target with multiple laser beams was explored for the possibility of improving the source's conversion efficiency.


A Mathematical Study Of Malaria Models Of Ross And Ngwa, William Plemmons Jan 2006

A Mathematical Study Of Malaria Models Of Ross And Ngwa, William Plemmons

Electronic Theses and Dissertations

Malaria is a vector borne disease that has been plaguing mankind since before recorded history. The disease is carried by three subspecies of mosquitoes Anopheles gambiae, Anopheles arabiensis and Anopheles funestu. These mosquitoes carry one of four type of Plasmodium specifically: P. falciparum, P. vivax, P. malariae or P. ovale. The disease is a killer; the World Health Organization (WHO) estimates that about 40% of the world's total populations live in areas where malaria is an endemic disease and as global warming occurs, endemic malaria will spread to more areas. The malaria parasite kills a child every 30 seconds. In …


Polarimetry Of Random Fields, Jeremy Ellis Jan 2006

Polarimetry Of Random Fields, Jeremy Ellis

Electronic Theses and Dissertations

On temporal, spatial and spectral scales which are small enough, all fields are fully polarized. In the optical regime, however, instantaneous fields can rarely be examined, and, instead, only average quantities are accessible. The study of polarimetry is concerned with both the description of electromagnetic fields and the characterization of media a field has interacted with. The polarimetric information is conventionally presented in terms of second order field correlations which are averaged over the ensemble of field realizations. Motivated by the deficiencies of classical polarimetry in dealing with specific practical situations, this dissertation expands the traditional polarimetric approaches to include …