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Full-Text Articles in Physical Sciences and Mathematics

Selection Of Stable Cultivars Using A Safety-First Rule, Kent M. Eskridge Jan 1990

Selection Of Stable Cultivars Using A Safety-First Rule, Kent M. Eskridge

Department of Statistics: Faculty Publications

The presence of genotype by environment interaction is of major concern to plant breeders, since large interactions can reduce gains from selection and complicate identification of superior cultivars. Numerous statistics have been proposed to characterize stability of cultivars, yet none of these methods explicitly indicate how stability may be combined with mean yield in choosing superior cultivars. It is assumed that the plant breeder prefers a cultivar with a small probability of low yield. Using a decision-theory concept known as safety-first to model such behavior, an index incorporating mean yield and stability is developed for each of four different definitions …


Ua56/1 Fact Book, Wku Institutional Research Jan 1990

Ua56/1 Fact Book, Wku Institutional Research

WKU Administration Documents

Statistical and demographic profile of WKU.


A Survey Using 14n:15n Natural Abundance Of The N Fixation By Pasture Legumes In The Field And Of Factors Affecting Fixation, P. Sanford Jan 1990

A Survey Using 14n:15n Natural Abundance Of The N Fixation By Pasture Legumes In The Field And Of Factors Affecting Fixation, P. Sanford

Experimental Summaries - Plant Research

Trial 89AL43, 90AL50, 90KO16

A preliminary survey using 14N:15N natural abundance to assess N2 fixation by pasture legumes in the field.

Location: Albany.

1. Develop a sampling methodology for the 1990 farm survey.
2. An initial assessment of nitrogen fixation by pasture legumes in the field.

Trial 90MT70

Using 14N:15N natural abundance to assess N2-fixation by subterranean clover.

Location Mount Barker Research Station

To examine symbiotic nitrogen fixation by subterranean clover, in detail, through one season in a productive pasture. To better assess the point in the season at which as one time sampling would most accurately determine the proportion …


A Model Of Dc Glow Discharges With Abnormal Cathode Fall, Karl H. Schoenbach, Hao Chen, G. Schaefer Jan 1990

A Model Of Dc Glow Discharges With Abnormal Cathode Fall, Karl H. Schoenbach, Hao Chen, G. Schaefer

Bioelectrics Publications

A model for an abnormal glow discharge, including a self‐consistent analysis of the cathode fall, was developed. It combines microscopic particle simulation by means of Monte Carlo methods with a fluid model of the gas discharge. The model allows calculations of the steady‐state electrical field distribution, the charged‐particle densities, and the current densities along the axis of the discharge. The model was used to simulate a glow discharge in 80% He and 20% SF6 at a pressure of 8 Torr with a current density of 1 A/cm2. The computed discharge voltage agrees well with measured values. The …


A Statistical Theory Of Digital Circuit Testability, Sharad C. Seth, Vishwani D. Agrawal, Hassan Farhat Jan 1990

A Statistical Theory Of Digital Circuit Testability, Sharad C. Seth, Vishwani D. Agrawal, Hassan Farhat

Mathematics Faculty Publications

When test vectors are applied to a circuit, the fault coverage increases. The rate of increase, however, could be circuit dependent. A relation between the average fault coverage and circuit testability is developed in this paper. The statistical formulation allows computation of coverage for deterministic and random vectors. We discuss the following applications of this analysis: determination of circuit testability from fault simulation, coverage prediction from testability analysis, prediction of test length, and test generation by fault sampling.


Identifying Directional Properties Of Spatial Point Patterns An Investigation Of Two Methods, Rolf Puchtinger Jan 1990

Identifying Directional Properties Of Spatial Point Patterns An Investigation Of Two Methods, Rolf Puchtinger

Theses and Dissertations (Comprehensive)

Analyses of spatial point patterns tend to focus on deviations from randomness by either clustering or regularity. One assumption of these analyses implies that the point generating process is equal in all directions. However, the association of the location of points with a process biased in one or more directions is widely neglected due to a lack of appropriate statistical procedures. This is surprising, since patterns generated by directional processes are important in Geography. The purpose of this thesis is to investigate the blunt-triangle method and the third moment method for their potential of identifying directionality in spatial point patterns. …


Regionalization Of Flood Data Using Probability Distributions And Their Parameters, Nageshwar Rao Bhaskar, Carol Alf O'Connor, Harold Andrew Myers, William Paul Puckett Dec 1989

Regionalization Of Flood Data Using Probability Distributions And Their Parameters, Nageshwar Rao Bhaskar, Carol Alf O'Connor, Harold Andrew Myers, William Paul Puckett

KWRRI Research Reports

The U. S. Geological survey recently used the method of residuals to delineate seven flood regions for the State of Kentucky. As an alternative approach, the FASTCLUS clustering procedure of the Statistical Analysis system (SAS) is used in this study to delineate five to six cluster regions in conjunction with statistical properties of the AMF series, like the coefficient of variation as estimated using method of L-moments, LCV, the parameters of the EVl and GEV flood frequency distributions, and the specific mean annual flood, QSP. For both cluster and USGS flood regions, regionalized flood frequency growth curves are developed and …


Regression Models For Bivariate Binary Responses, Juni Palmgren Nov 1989

Regression Models For Bivariate Binary Responses, Juni Palmgren

UW Biostatistics Working Paper Series

We discuss maximum likelihood inference for the bivariate logistic model, specified in terms of the marginal logits and the log odds ratio. Using the exponential family nonlinear model formulation the model fitting can be done in GLIM. The procedure is illustrated by modelling survival of unilateral and bilateral total hip arthroplasties as function of patient specific and hip specific covariates. We compare maximum likelihood inference with inference obtained from solving likelihood equations under the assumption of within block independence and using robust standard errors for the estimates. Simulations indicate that the latter procedure is effcient for block specific covariates but …


Fisheries Report No 82 - Effects Of Fish Trapping On The Shark Bay Snapper Fishery, M. J. Moran, J. Jenke Oct 1989

Fisheries Report No 82 - Effects Of Fish Trapping On The Shark Bay Snapper Fishery, M. J. Moran, J. Jenke

Fisheries Research Reports

Traps have been a controversial method of catching pink snapper Chrysophrys auratus (Sparidae) around Shark Bay, Western Australia, since 1959. The history of the issue and the relevant regulations are reviewed; and results of in­vestigations into specific concerns about trap fishing are reported. Concerns of ghost-fishing by lost traps have been largely allayed by underwater TV film of snapper escaping from a standard snapper trap.

A major concern was that traps might physically damage the benthic fauna, e.g. corals. A TV survey showed that while fragile hard corals are abundant in shallower water nearby, the deeper snapper grounds themselves are …


Student Fact Book, Fall 1989, Wright State University 25 Years Vision Unlimited, Office Of Student Information Systems, Wright State University Oct 1989

Student Fact Book, Fall 1989, Wright State University 25 Years Vision Unlimited, Office Of Student Information Systems, Wright State University

Wright State University Student Fact Books

The student fact book has general demographic information on all students enrolled at Wright State University for Fall Quarter, 1989.


Spatial Critical Points Of Solutions Of A One-Dimensional Nonlinear Parabolic Problem, Larry Turyn Aug 1989

Spatial Critical Points Of Solutions Of A One-Dimensional Nonlinear Parabolic Problem, Larry Turyn

Mathematics and Statistics Faculty Publications

The number of spatial critical points is nonincreasing in time, for positive, analytic solutions of a scalar, nonlinear, parabolic partial differential equation in one space dimension. While proving this, we answer the question: What happens to a critical point which loses simplicity?


Effect Of Photoperiod On Developmental Morphology And Enolase Isoenzyme Immunohistochemistry In Rat And Djungarian Hamster Superficial Pineal Glands, Chalmer D. Mcclure Aug 1989

Effect Of Photoperiod On Developmental Morphology And Enolase Isoenzyme Immunohistochemistry In Rat And Djungarian Hamster Superficial Pineal Glands, Chalmer D. Mcclure

Loma Linda University Electronic Theses, Dissertations & Projects

The best understood functional activity of the pineal gland is its diurnal production of melatonin in response to environmental lighting cues. Several enzymes of the melatonin pathway respond to daily photoperiod changes, for example hydroxyindole-O-methyltransferase (HIOMT) and serotonin N-acetyltransferase (SNAT). Increased levels of the glycolytic enzyme neuron-specific enolase (NSE) are thought to reflect increased physiological demands placed on neurons and neuroendocrine tissues. Homodimer non-neuronal enolase isoenzyme (NNE) is immunolocalized to cells, and the hybrid enolase (consisting of subunits from NSE and NNE) has been seen in cerebellar stellate and basket cells. Although not rate limiting, concentrations of both NSE and …


Detection Of Outliers And Influential Observations In Regression Models, Anwar M. Hossain Jul 1989

Detection Of Outliers And Influential Observations In Regression Models, Anwar M. Hossain

Mathematics & Statistics Theses & Dissertations

Observations arising from a linear regression model, lead one to believe that a particular observation or a set of observations are aberrant from the rest of the data. These may arise in several ways: for example, from incorrect or faulty measurements or by gross errors in either response or explanatory variables. Sometimes the model may inadequately describe the systematic structure of the data, or the data may be better analyzed in another scale. When diagnostics indicate the presence of anomalous data, then either these data are indeed unusual and hence helpful, or contaminated and, therefore, in need of modifications or …


Mathematical Models Of Prevascular Tumor Growth By Diffusion, Sophia A. Maggelakis Jul 1989

Mathematical Models Of Prevascular Tumor Growth By Diffusion, Sophia A. Maggelakis

Mathematics & Statistics Theses & Dissertations

A study of several complementary mathematical models that describe the early, prevascular stages of solid tumor growth by diffusion under various simplifying assumptions is presented. The advantage of these models is that their degree of complexity is relatively low, which ensures fairly straightforward comparisons with experimental or clinical data (as it becomes available), yet they are mathematically sophisticated enough to capture the main biological phenomena of interest.

The tumor growth and cell proliferation rate are assumed to depend on the local concentrations of nutrients and inhibitory factors. The effects of geometry and spatially non-uniform inhibitor production and non-uniform nutrient consumption …


Software Reliability Models, Syed Afzal Hossain Jul 1989

Software Reliability Models, Syed Afzal Hossain

Mathematics & Statistics Theses & Dissertations

The problem considered here is the building of Non-homogeneous Poisson Process (NHPP) model. Currently existing popular NHPP process models like Goel-Okumoto (G-O) and Yamada et al models suffer from the drawback that the probability density function of the inter-failure times is an improper density function. This is because the event no failure in (0, oo] is allowed in these models. In real life situations we cannot draw sample(s) from such a population and also none of the moments of inter-failure times exist. Therefore, these models are unsuitable for modelling real software error data. On the other hand if the density …


Anthropometric Parameters In Public School Students And Seventh-Day Adventist Vegetarian And Meat-Eating Students, Joan Sabaté-Casellas Jun 1989

Anthropometric Parameters In Public School Students And Seventh-Day Adventist Vegetarian And Meat-Eating Students, Joan Sabaté-Casellas

Loma Linda University Electronic Theses, Dissertations & Projects

Concerns have been expressed for the ability of some vegetarian diets to support normal growth of children. Animal protein or meat intake showed a positive relationship to attained height in children from developing countries. In this study, the relationship between meat intake/vegetarian status and physical growth was investigated in children living in California.

Height and weight were collected on 2,272 Caucasian children aged 6-18 years attending Seventh-day Adventist (SDA) or public schools who participated in a two year longitudinal study. Age-, sex-, and school-specific mean heights and weights were at or above the national reference values. Sex-specific, age-adjusted regression analysis …


Responses To Corporate Versus Individual Wrongdoing, Valerie P. Hans, M. David Ermann Jun 1989

Responses To Corporate Versus Individual Wrongdoing, Valerie P. Hans, M. David Ermann

Cornell Law Faculty Publications

For many years, researchers assumed that the public was indifferent to corporate wrongdoing, but recent surveys have discovered evidence to the contrary. Taking insights from these data a step further, this study employed an experimental design to examine whether people responded differently to corporate versus individual wrongdoers. We varied the identity of the central actor in a scenario involving harm to workers. Half the respondents were informed that a corporation caused the harm; the remainder were told that an individual did so. Respondents applied a higher standard of responsibility to the corporate actor. For identical actions, the corporation was judged …


Misfit Between Motivational Style And Type Of Job Demand As A Factor In Developing Occupational Stress, Arlene Gray Blix Jun 1989

Misfit Between Motivational Style And Type Of Job Demand As A Factor In Developing Occupational Stress, Arlene Gray Blix

Loma Linda University Electronic Theses, Dissertations & Projects

Occupational stress is costly in terms of human suffering and impaired organizational effectiveness. Occupational stress involves the interface between the individual worker and the work environment. The purpose of the study was to analyze the fit between motivational style and the type of job demands as a contributing factor in developing occupational stress symptoms. A literature review of occupational stress models was conducted. The six models compared and contrasted included the Person-Environment fit model (French, Rodgers, & Cobb, 1974), Integrative Transactional Model (Schuler, 1982), Organizational Stress Models (Ivancevich & Matteson, 1987; Parker & DeCotiis, 1983), Facet Analysis Model (Beehr & …


Feasibility Of An Extraoral Method For Predicting Manibular Incisor Relapse, Mark J. Saylor Jun 1989

Feasibility Of An Extraoral Method For Predicting Manibular Incisor Relapse, Mark J. Saylor

Loma Linda University Electronic Theses, Dissertations & Projects

The author undertook to develop an extraoral model for predicting mandibular incisor relapse similar to the model described by Harvey and Sheldon Peck. Whereas the Peck and Peck method involves intraoral measurements, the method described in this paper relied on the taking of measurements from the patient's pre-treatment plaster models. Two hundred and sixty teeth were measured both orally and on plaster casts, and several statistical tests were performed to isolate any differences between the intraoral and extraoral methods. The principal difference was identified as the faciolingual measurement of the incisor, due to the height of contour often being subgingival …


Facial Typing Methods : A Comparative Study, James A. Grabow Jun 1989

Facial Typing Methods : A Comparative Study, James A. Grabow

Loma Linda University Electronic Theses, Dissertations & Projects

Facial typing methods are used to determine to which of three basic facial pattern categories an individual patient belongs. These three categories are mesofacial, brachyfacial, and dolichofacial. It is important to establish the correct facial type because the reaction to treatment mechanics and the stability of the denture is dependent upon the analysis of the facial patterns. The purpose of this paper was to show a comparative study of facial typing classification methods used on 100 patients (47 boys and 53 girls). The eight different methods used were as follows: Bioprogressive, Ricketts LLU1, LLU2, QuickCeph™, Jarabak, Facial-Mandibular Index, and Steiner. …


Some Estimates For Finite Difference Approximations, José-Luis Menaldi May 1989

Some Estimates For Finite Difference Approximations, José-Luis Menaldi

Mathematics Faculty Research Publications

Some estimates for the approximation of optimal stochastic control problems by discrete time problems are obtained. In particular an estimate for the solutions of the continuous time versus the discrete time Hamilton-Jacobi-Bellman equations is given. The technique used is more analytic than probabilistic.


Probability Of Discrete Failures, Weibull Distribution, Mary Jo Hansen May 1989

Probability Of Discrete Failures, Weibull Distribution, Mary Jo Hansen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The intent of this research and these is to describe the development of a series of charts and tables that provide the individual and cumulative probabilities of failure applying to the Weibull statistical distribution. The mathematical relationships are developed and the computer programs are described for deterministic and Monte Carlo models that compute and verify the results. Charts and tables reflecting the probabilities of failure for a selected set of parameters of the Weibull distribution functions are provided.


Coefficients Of Multiple Determination Based On Rank Estimates, Lee D. Witt Apr 1989

Coefficients Of Multiple Determination Based On Rank Estimates, Lee D. Witt

Dissertations

No abstract provided.


Pattern Analysis : A Descriptive Introduction, J. F. Wallace, Australian Co-Operation With The National Agricultural Research Project, Thailand. Apr 1989

Pattern Analysis : A Descriptive Introduction, J. F. Wallace, Australian Co-Operation With The National Agricultural Research Project, Thailand.

All other publications

Notes for a workshop on pattern analysis of germplasm data ; to be held at the Pathumk Thani Rice Research Centre, May-June 1989. At head of title : Australian Co-operation with the National Agricultural Research Project Thailand.

Pattern analysis is a term which covers a very large area of statistical analysis for multivariate data sets. A full understanding of pattern analysis would require years of study of mathematical concepts and computing algorithms. Fortunately, pattern analysis methods can now be used without all this specialist knowledge. This is possible because of the availability of computer programs such as PATN, which is …


Optimal Row-Column Designs For Correlated Errors And Nested Row-Column Designs For Uncorrelated Errors, Nizam Uddin Apr 1989

Optimal Row-Column Designs For Correlated Errors And Nested Row-Column Designs For Uncorrelated Errors, Nizam Uddin

Mathematics & Statistics Theses & Dissertations

In this dissertation the design problems are considered in the row-column setting for second order autonormal errors when the treatment effects are estimated by generalized least squares, and in the nested row-column setting for uncorrelated errors when the treatment effects are estimated by ordinary least squares. In the former case, universal optimality conditions are derived separately for designs in the plane and on the torus using more general linear models than those considered elsewhere in the literature. Examples of universally optimum planar designs are given, and a method is developed for the construction of optimum and near optimum designs, that …


Design And Statistical Analysis Of Plant Protection Experiment, J F. Wallace Mar 1989

Design And Statistical Analysis Of Plant Protection Experiment, J F. Wallace

All other publications

An Australian co-operation with the national agricultural research project Thailand.

This short course is intended to cover aspects of experimental design, sampling and statistical analysis for researchers in Entomology and Plant Pathology.

The basic principles of experimental design are the same for plant protection research as they are in other areas of research. Problems in plant protection arise from the variation of the data, the complexity of the systems and interactions with environmental factors. In many cases, standard designs are quite adequate.


Robustness & Precision Of Parametric & Distribution-Free Tolerance Limits For Two Lifetime Distributions, Wei Kei Shiue, Lee J. Bain Jan 1989

Robustness & Precision Of Parametric & Distribution-Free Tolerance Limits For Two Lifetime Distributions, Wei Kei Shiue, Lee J. Bain

Mathematics and Statistics Faculty Research & Creative Works

Exact parametric tolerance limits or confidence limits on reliability are not available for the gamma distribution, and it is, difficult to determine approximate methods which are accurate for all parameter values. The precision lost by using the distribution-free tolerance-limit method based on the first order statistic, compared to using an approximate gamma tolerance limit method is studied. The robustness of the approximate gamma tolerance limit when the true model is Weibull and the robustness of a Weibull tolerance limit when the true model is gamma are also studied. The efficiency of the distribution-free method ranges from about 0.60 to 0.90 …


Periodic Points For Homeomorphisms Of Hereditarily Decomposable Chainable Continua, W. T. Ingram Jan 1989

Periodic Points For Homeomorphisms Of Hereditarily Decomposable Chainable Continua, W. T. Ingram

Mathematics and Statistics Faculty Research & Creative Works

In this paper it is shown that homeomorphisms of hereditarily decomposable chainable continua cannot have periodic points whose periods are not powers of two. Examples show that for each power of two there is a hereditarily decomposable chainable continuum and a homeomorphism of it which has a periodic point of period that power of two. © 1989 American Mathematical Society.


Sharp Lower Bounds For A Generalized Jensen Inequality, A. K. Rigler, S. Y. Trimble, R. S. Varga Jan 1989

Sharp Lower Bounds For A Generalized Jensen Inequality, A. K. Rigler, S. Y. Trimble, R. S. Varga

Mathematics and Statistics Faculty Research & Creative Works

No abstract provided.


Ua56/1 Fact Book, Wku Institutional Research Jan 1989

Ua56/1 Fact Book, Wku Institutional Research

WKU Administration Documents

Statistical and demographic profile of WKU.