Physical Sciences and Mathematics Commons^™

Juxtaposition At 45 Km Of Temperatures From Rayleigh-Scatter Lidar And Reanalysis Models, David K. Moser

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Weather and climate forecasts are almost exclusively produced by computer models, which use atmospheric measurements as starting points. It is a well-known and joked-about fact that model predictions can be incorrect at times. One of the reasons this happens is due to gaps in our knowledge of atmospheric conditions in areas where measurements don’t often taken place, such as the mesosphere, which stretches from roughly 45-90 km altitude.

A lidar is a device that can shoot out short bursts of laser light to measure things such as atmospheric thickness at a distance. From this information one can then derive the …

Comparison Of Survival Curves Between Cox Proportional Hazards, Random Forests, And Conditional Inference Forests In Survival Analysis, Brandon Weathers

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Survival analysis methods are a mainstay of the biomedical fields but are finding increasing use in other disciplines including finance and engineering. A widely used tool in survival analysis is the Cox proportional hazards regression model. For this model, all the predicted survivor curves have the same basic shape, which may not be a good approximation to reality. In contrast the Random Survival Forests does not make the proportional hazards assumption and has the flexibility to model survivor curves that are of quite different shapes for different groups of subjects. We applied both techniques to a number of publicly available …

Compilation And Comparison Of Electron Penetration Ranges As A Function Of Effective Number Of Valence Electrons, Teancum Quist

Senior Theses and Projects

The continuous-slow-down approximation (CSDA) is used to create a simple composite analytical formula to estimate the range or maximum penetration depth of bombarding electrons into traditional materials including conductors, semiconductors, and insulators. This formula generates an approximation to the range using a single fitting parameter, N_v, described as the effective number of valence electrons. This applicability of the formulation extends to electrons with energies from 10MeV. These calculations are of great value for studies of high electron bombardment, such as electron spectroscopy or the vacuum of space. A list comprised of 187 materials has been collected that greatly …

Intercomparison Of Prism And Daymet Temperature Interpolation From 1980 To 2003, Rebecca A. Scully

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As ecosystem modeling becomes increasingly integrated with Geographic Information Systems (GIS) there is a rise in demand for spatially and temporally continuous meteorological data. But in order to justify management decisions or to provide robust scientific insights, the accuracy of meteorological data used as model input must be thoroughly quantified. Current methods to create spatially continuous climate data from discrete weather station data include inverse distance weighting, geostatistical techniques such as kriging and splines, local regression models such as Parameter-Elevation Regression on Independent Slope Model (PRISM) and Daymet, and regional regression models. For the conterminous United States, PRISM and Daymet …

A Comparison Of Prediction Methods Of Functional Autoregressive Time Series, Devin Didericksen

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Functional data analysis (FDA) is a relatively new branch of statistics that has seen a lot of expansion recently. With the advent of computer processing power and more efficient software packages we have entered the beginning stages of applying FDA methodology and techniques to data. Part of this undertaking should include an empirical assessment of the effectiveness of some of the tools of FDA, which are sound on theoretical grounds. In a small way, this project helps advance this objective.

This work begins by introducing FDA, scalar prediction techniques, and the functional autoregressive model of order one - FAR(1). Two …

Cow Insurance Vs. Human Insurance: A Comparison Study, Corlan Fawcett

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

This paper will compare the premiums to insure cows and humans for n-year term, n-year endowment, and whole life insurance. It will go into more depth for whole life premium s that would be charged, such that the insurance company is 95 percent confident that they will not lose money. In particular the paper will look at how the variance affects the premiums for an insurance company insuring 100 cows.

Comparison Of Exact Methods For Analyzing Family-Based Samples, Abbie Lundgreen

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Family-based association tests are used to identify genes that increase the risk of developing a disease, while controlling for spurious associations caused by population structure. The exact family-based association test, exact FBAT, is a unified approach which can be app lied to tests of different genetic models, sampling designs, null hypotheses , and missing parental information.

The purpose of this report is to compare the power of the exact FBAT with two other tests, exact conditional logistic regression (CLR) and the exact trend test for clustered data (QEM). Pedigrees of sibships were simulated based upon a variety of different parameters, …

Comparison Between Hydrogen And Dihydrogen Bonds Among H3bnh3, H2bnh2, And Nh3, T. Kar, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

Several possible binary complexes among ammonia-borane, aminoborane, and ammonia, via hydrogen and/or dihydrogen bonds, have been investigated to understand the effect of different hybridization. Møller–Plesset second-order perturbation theory with aug-cc-pVDZ basis set was used. The interaction energy is corrected for basis set superposition error, and the Morokuma–Kitaura method was employed to decompose the total interaction energy. Like H₃BNH₃, the sp² hybridized H₂BNH₂ also participates in H- and dihydrogen bond formation. However, such bonds are weaker than their sp³ analogs. The contractions of BN bonds are associated with blueshift in …

Comparison Of Methods For Calculating The Properties Of Intramolecular Hydrogen Bonds. Excited State Proton Transfer, T. Kar, Steve Scheiner, M. Cuma

Steve Scheiner

A series of molecules related to malonaldehyde, containing an intramolecular H-bond, are used as the testbed for a variety of levels of ab initio calculation. Of particular interest are the excitation energies of the first set of valence excited states, nπ^∗ and ππ^∗, both singlet and triplet, as well as the energetics of proton transfer in each state. Taking coupled cluster results as a point of reference, configuration interaction-singles–second-order Møller–Plesset (CIS–MP2) excitation energies are too large, as are CIS to a lesser extent, although these approaches successfully reproduce the order of the various states. The …

Comparison Of Methods For Calculating The Properties Of Intramolecular Hydrogen Bonds. Excited State Proton Transfer, T. Kar, Steve Scheiner, M. Cuma

Chemistry and Biochemistry Faculty Publications

A series of molecules related to malonaldehyde, containing an intramolecular H-bond, are used as the testbed for a variety of levels of ab initio calculation. Of particular interest are the excitation energies of the first set of valence excited states, nπ^∗ and ππ^∗, both singlet and triplet, as well as the energetics of proton transfer in each state. Taking coupled cluster results as a point of reference, configuration interaction-singles–second-order Møller–Plesset (CIS–MP2) excitation energies are too large, as are CIS to a lesser extent, although these approaches successfully reproduce the order of the various states. The …

Comparison Between Calculatedand Observed F-Region Density Profiles At Jicamarca, Peru, A. J. Preble, D. N. Anderson, Bela G. Fejer, P. H. Doherty

Bela G. Fejer

Electron density profiles and isodensity contours derived from Jicamarca incoherent scatter radar observations in Peru for October 1–2, 1970, are compared in detail with results from the Phillips Laboratory global theoretical ionospheric model. This model solves the ion continuity equation for O+ concentration through production, loss, and transport of ionization. The primary factor controlling the peak plasma density at Jicamarca is the vertical E×B drift, which drives the ionization upward during the day and downward at night. When we use the measured drift in the model, we achieve excellent results with the measured electron density profiles. We illustrate the sensitivity …

A Comparison Of Two Linear Nonparametric Regression Techniques, Sylvain Sardy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis presented a useful tool in regression. Nonparametric linear regression techniques were described in the general context of regression. A comparison of two of these techniques, kernel regression and iterative regression, showed various aspects of nonparametric linear regressors.

A Comparison Of Estimation Procedures For The Beta Distribution, Huey Yan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The beta distribution may be used as a stochastic model for continuous proportions in many situations in applied statistics. This thesis was concerned with estimation of the parameters of the beta distribution in three different situations.

Three different estimation procedures-the method of moments, maximum likelihood, and a hybrid of these two methods, which we call the one-step improvement-were compared by computer simulation, for beta data and beta data contaminated by zeros and ones. We also evaluated maximum likelihood estimation in the context of censored data, and Newton's method as a numerical procedure for solving the likelihood equations …

The Longitude Dependence Of The Dayside F Region Trough: A Detailed Model-Observation Comparison, Jan Josef Sojka, Robert W. Schunk, J. A. Whalen

All Physics Faculty Publications

The nighttime main F region trough extends into the sunlit afternoon sector. This trough feature exhibits both a strong magnetic activity dependence and a longitude (UT) dependence. Whalen (1987), using International Geophysical Year (IGY) ionosonde data, showed that both of these effects are readily extracted from ƒ_oF₂ observations. In this study we show that the longitude effect is the same as that contained in the Utah State University time-dependent ionospheric model. It arises from the offset of the geomagnetic axis from the geographic axis. The magnetic activity dependency is associated with the westward convection in the afternoon …

Comparison Of Bootstrap With Other Tests For Several Distributions, Yu-Yu Wong

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This paper discusses results of a computer simulation to investigate several different tests when sampling several distributions. The hypothesis H₀: μ=0 was tested against H₀: μ≠0, using the usual t-test, trimmed t-test, the Jackkinfe, the Bootstrap and signed-rank test. The p-values and empirical power show that the Bootstrap is as good as the t-test. The Jackknife procedure is too liberal, always obtaining small p-values. The signed-rank is a fairly good test if the data follows the Cauchy Distribution.

Comparison Of Simultaneous Chatanika And Millstone Hill Temperature Measurements With Ionospheric Model Predictions, C. E. Rasmussen, Jan Josef Sojka, Robert W. Schunk, Vincent B. Wickwar, O. De La Beaujariere, J. Foster, J. Holt

All Physics Faculty Publications

As part of the MITHRAS program, the Chatanika and Millstone Hill incoherent scatter radars made coordinated observations of the polar ionosphere on June 27 and 28, 1981. The temperature data obtained during these days were compared with predictions made by a high-latitude ionospheric model. The comparison of the temperature measurements and the results of the ionospheric model depend on the assumptions made both in reducing the data and on the inputs that are needed by the model. The deduction of electron temperature from radar measurements depends upon a knowledge of the mean ion mass as a function of altitude. The …

Comparison Of Proton Transfers In (S2h5)+ And (O2h5)+, L. Bigham, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

The energetics and electronic rearrangements associated with proton transfer between S atoms in (H₂S–H–SH₂)⁺ are calculated using ab initio molecular orbital methods and compared with similar data in the first‐row analog (H₂O–H–OH₂)⁺. The full potential energy surface of (S₂H₅)⁺, calculated as a function of the H‐bond length as well as the position of the proton, contains two equivalent minima separated by a small energy barrier, whereas the surface of (O₂H₅)⁺ contains a single minimum corresponding to a symmetric …

Comparison Of Bootstrap And Jacknife Statistical Procedures, Amanuel Gobena

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

This report compares the bootstrapping to jacknifing statistical procedures in terms in bias, confidence interval and estimation of median. Related literature have been reviewed. A bootstrap allows a researcher to get an approximation to the distribution of possibly complicated statistical summaries. It is based on random sampling with replacement from experimental units. Jacknife has also been in operation prior to bootstrapping statistical procedure. The jacknife divides the data into subgroups and obtains partial estimates of these subgroups by omitting one subgroup at a time. When both of these statistical resampling procedures are compared the bootstrap has less bias, more accurate …

Ab Initio Comparison Of H Bonds And Li Bonds. Complexes Of Lif, Licl, Hf, And Hcl With Nh3, Z. Latajka, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

Ab initio calculations are carried out on the complexes H₃N–LiF, H₃N–LiCl and their analogs H₃N–HF and H₃N–HCl as well as the isolated subunits. Double‐zeta basis sets, augmented by two sets of polarization functions, are used in conjunction with second‐order Moller–Plesset perturbation theory (MP2) for evaluation of electron correlation effects. The Li bonds are found to be substantially stronger than their H‐bonding counterparts, due in large measure to the greater dipole moments of the LiX subunits. Correlation has a large effect on the geometry and energetics of …

Theoretical Study Of H2o–Hf And H2o–Hcl: Comparison With Experiment, M. M. Szczesniak, Steve Scheiner, Y. Bouteiller

Chemistry and Biochemistry Faculty Publications

The H bonds in H₂O–HF and H₂O–HCl are studied and compared using ab initio molecular orbital methods and the results compared to experimental data. Basis sets used are: (i) triple valence 6‐311G∗∗ and (ii) double ζ with two sets of polarization functions. Electron correlation, included via second‐ and third‐order Møller–Plesset perturbation theory, is found to have profound effects on both systems, particularly H₂O–HCl. Both H bonds are strengthened substantially with a concomitant reduction in length. H‐bond energies and geometries calculated at correlated levels are in excellent accord with …

Tree Diameter Measurements At English And Metric Standard Heights: A Comparison, United States Department Of Agriculture, Forest Service

Forestry

The impact of measuring trees at 1.3 m versus 1.37 m heights above ground line was analyzed. The results indicate that the difference in diameter measurement taken at the two points averages around 1 percent. An equation for converting from English diameter at breast height to the metric equivalent of 1.3 m is presented.

Comparison Of Model High-Latitude Electron Densities With Millstone Hill Observations, Jan Josef Sojka, Robert W. Schunk, J. V. Evans, J. M. Holt, R. H. Wand

All Physics Faculty Publications

Model predictions of the diurnal variations of plasma convection velocities and electron densities in the high-latitude ionosphere were compared with Millstone Hill incoherent scatter radar observations for an equinox day on which there was moderate magnetic activity. On the observation day, three major morphological features were evident at 500 km, including a dayside high density region, a nightside mid-latitude trough, and a region of slightly enhanced densities in the auroral zone. Although the dayside high density region was due to solar EUV radiation, it was not symmetrical about local noon (1000-1900 LT sector) owing to the effect of horizontal transport. …

Comparison Of Proton Transfers In Cationic Heterodimers And Homodimers Of Nh3 And Oh2, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

Ab initio molecular orbital methods are used to study proton transfers in the cationic heterodimer (H₃NHOH₂)⁺ as well as the symmetric homodimers (H₂OHOH₂)⁺ and (H₃NHNH₃)⁺. All calculations are carried out at the Hartree–Fock level with a 4‐31G basis set to ensure consistency. For proton transfers along a linear hydrogen bond in the heterodimer, asymmetric single‐well potentials with a minimum corresponding to (NH₄)⁺(OH₂) are obtained for R(NO) distances of less than 2.85 …

High-Latitude Convection: Comparison Of A Simple Model With Incoherent Scatter Observations, Jan Josef Sojka, J. C. Foster, W. J. Raitt, Robert W. Schunk, J. R. Doupnik

All Physics Faculty Publications

We have compared a simple model of plasma convection at high latitudes with data obtained from simultaneous measurements made by the incoherent scatter facilities at Chatanika, Alaska and Millstone Hill, Massachusetts in June 1978 during moderately disturbed conditions. The measured horizontal plasma drift velocities were averaged for four days to emphasize gross features of the convection pattern and reduce the effects of substorms. The convection model includes the offset of 11.5° between the geographic and geomagnetic poles, the tendency of plasma to corotate about the geographic pole, and a constant dawn/dusk magnetospheric electric field mapped to a circle about a …

Evaluation Of An Experiment After Analysis Of Variance, Abdullah Sulaiman Atheem

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

If experimental data are obtained according to an experimental design for which analysis of variance (AOV) is appropriate, the result of the analysis is one of the following decisions:

1. A significant difference exists among treatment effects.

2. No significant difference exists.

Interpretation in the first case has been studied very thoroughly by many statisticians resulting, for example, in the multiple comparison procedure. Too often, in the second case, the AOV analysis is thought to be completed with no further attempt to interpret a nonsignificant outcome.

Of the many possible explanations for significance in the first case, the multiple comparison …

Comparison Of Transition Matrices Between Metropolitan And Non-Metropolitan Areas In The State Of Utah Using Juvenile Court Data, Sung-Ik Song

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this paper is to use Markov Chains for the study of youths referred to the juvenile court in the metropolitan and non-metropolitan areas of the state of Utah.

Two computer programs were written for creating case histories for each person referred to the court and for testing for the significance of the difference among several transition matrices.

Another computer program, which was written by Soo Hong Uh, was used for analyzing realizations of a Markov chains up to the 4th order; a third computer program, originally written by David White, was used for interpreting Markov chains.

The …

A Monte Carlo Comparison Of Nonparametric Reliability Estimators, Jia-Jinn Yueh

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

It is very difficult to construct a reliability model for a complex system. However, the reliability model for a series configuration is relatively simple. In the simplest case in which the components are mutually independent, the system reliability can be represented as follows:

R_s(x) = ∑ⁿ_i=1R_i(x),

where R_i is the reliability for the i^th component. It is also known that for moderate levels of system reliability for large systems, the component reliability must be high.

Extreme Value Theory indicates that under very general conditions, the initial form of the distribution function …