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Full-Text Articles in Physical Sciences and Mathematics

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 …


Models Of Forbidden Line Emission Profiles From Axisymmetric Stellar Winds., Richard Ignace, A. Brimeyer Sep 2006

Models Of Forbidden Line Emission Profiles From Axisymmetric Stellar Winds., Richard Ignace, A. Brimeyer

ETSU Faculty Works

A number of strong infrared forbidden lines have been observed in several evolved Wolf–Rayet (WR) star winds, and these are important for deriving metal abundances and testing stellar evolution models. In addition, because these optically thin lines form at large radius in the wind, their resolved profiles carry an imprint of the asymptotic structure of the wind flow. This work presents model forbidden line profile shapes formed in axisymmetric winds. It is well known that an optically thin emission line formed in a spherical wind expanding at constant velocity yields a flat-topped emission profile shape. Simulated forbidden lines are produced …


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 …


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}


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 …


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 …


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 …


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.


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 …


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 …


Microlensing Of Circumstellar Envelopes Iii. Line Profiles From Stellar Winds In Homologous Expansion., M. Hendry, Richard Ignace, H. Bryce May 2006

Microlensing Of Circumstellar Envelopes Iii. Line Profiles From Stellar Winds In Homologous Expansion., M. Hendry, Richard Ignace, H. Bryce

ETSU Faculty Works

This paper examines line profile evolution due to the linear expansion of circumstellar material obsverved during a microlensing event. This work extends our previous papers on emission line profile evolution from radial and azimuthal flow during point mass lens events and fold caustic crossings. Both “flavours” of microlensing were shown to provide effective diagnostics of bulk motion in circumstellar envelopes. In this work a different genre of flow is studied, namely linear homologous expansion, for both point mass lenses and fold caustic crossings. Linear expansion is of particular relevance to the effects of microlensing on supernovae at cosmological distances. We …


The Polarization Signature From Microlensing Of Circumstellar Envelopes In Caustic Cossing Events, Richard Ignace, J. Bjorkman, H. Bryce Feb 2006

The Polarization Signature From Microlensing Of Circumstellar Envelopes In Caustic Cossing Events, Richard Ignace, J. Bjorkman, H. Bryce

ETSU Faculty Works

In recent years, it has been shown that microlensing is a powerful tool for examining the atmospheres of stars in the Galactic bulge and Magellanic Clouds. The high gradient of magnification across the source during both small impact parameter events and caustic crossings offers a unique opportunity for determining the surface brightness profile of the source. Furthermore, models indicate that these events can also provide an appreciable polarization signal: arising from differential magnification across the otherwise symmetric source. Earlier work has addressed the signal from a scattering photosphere for both point mass lenses and caustic crossings. In a previous paper, …