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A Model Of Data Structures Commonly Used In Programming Languages And Data Base Management Systems, William L. Honig Jan 1975

A Model Of Data Structures Commonly Used In Programming Languages And Data Base Management Systems, William L. Honig

Computer Science: Faculty Publications and Other Works

This thesis claims that contemporary data structures can be understood and studied with an intelligible model which captures their essential differences and similarities and, further, that such a model is an appropriate basis for a top-down description method for data structures. To define the scope of the model, the data structures included in 21 programming languages and data base management systems have been tabulated. Each individual data structure is illustrated with an example drawn from a published paper or a working computer program. This mélange of data structures is divided into three classes (aggregates, associations , and files) and each …


The Keller Plan In College Introductory Physical Geology : A Comparison With The Conventional Teaching Method, Robert G. Walsh Sr. Jan 1975

The Keller Plan In College Introductory Physical Geology : A Comparison With The Conventional Teaching Method, Robert G. Walsh Sr.

Theses and Dissertations

The purpose of this study is to compare the learning and attitudinal changes that took place in a college introductory physical geology class between a self-paced method of instruction called the Keller Plan and the conventional lecture-laboratory method.

The sample population was 56 students enrolled in Earth Science 120, an introductory physical geology course at Minot State College ·~ during the fall quarter, 1973. An experimental section of 20 students experienced the Keller Plan treatment and two control groups consisting of 18 students each received the conventional method of instruction.

Four specific areas of investigation were tested: (1) knowledge of …


Measurement Of Growth Rate To Determine Condensation Coefficients For Water Drops Grown On Natural Cloud Nuclei., A. M. Sinnarwalla, Darryl J. Alofs, J. C. Carstens Jan 1975

Measurement Of Growth Rate To Determine Condensation Coefficients For Water Drops Grown On Natural Cloud Nuclei., A. M. Sinnarwalla, Darryl J. Alofs, J. C. Carstens

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Growth Rate Measurements Were Made for Water Drops Grown on Nuclei in Atmospheric Air Samples Taken in Rolla, Missouri. Rolla, Having a Population of 15,000 and Very Little Industry, is Relatively Free of Urban Pollutants. the Measurements Were Made in a Vertical Flow Thermal Diffusion Chamber at Supersaturations of 0. 5 and 1%. the Time to Grow from Near Dry Radius to the Final Radius (6 to 7. 5 Mu M) Was Measured. If One Assumes the Thermal Accomodation Coefficient is Unity, the Measurements Indicate an Average Value of 0. 026 for the Condensation Coefficient. the Temperature Ranged from 22. …


Texas Eastern University Catalog, 1975-1976, University Of Texas At Tyler Jan 1975

Texas Eastern University Catalog, 1975-1976, University Of Texas At Tyler

Catalogs

No abstract provided.


Multimedia Dispersion Relation For Surface Electromagnetic Waves, C. A. Ward, K. Bhasin, Robert John Bell, Ralph William Alexander, I. Tyler Jan 1975

Multimedia Dispersion Relation For Surface Electromagnetic Waves, C. A. Ward, K. Bhasin, Robert John Bell, Ralph William Alexander, I. Tyler

Physics Faculty Research & Creative Works

We Have Derived a General, N-Media Dispersion Relation for Surface Electromagnetic Waves Propagating on Isotropic Layers with Complex Dielectric Functions. the Equation is Presented in a Convenient, Compact Form for Ease of Application. Copyright © 1975 American Institute of Physics.


Strain Effects On The Esr Spectrum From Antimony Donors In Germanium, Edward Boyd Hale, John R. Dennis, Shih Hua Pan Jan 1975

Strain Effects On The Esr Spectrum From Antimony Donors In Germanium, Edward Boyd Hale, John R. Dennis, Shih Hua Pan

Physics Faculty Research & Creative Works

The electron-spin-resonance spectra from surface-strained (but not externally stressed) antimony-doped germanium are investigated in detail. Experimental data are given for the linewidth, line asymmetry, and line-shape reversal feature as well as for the changes in donor concentration, temperature, and surface conditions. The donors of interest occur in a surface layer several microns thick. A theoretical analysis is based on the Kohn-Luttinger formulation for a shallow donor electron, which is forced by surface strain to predominately occupy a [111] conduction-band valley minimum. A substantial distribution in strain among the donor sites is necessary to account for the line-structure features. These features …


Electron Impact Autoionization In Heavy Alkali Metals, Kaare J. Nygaard Jan 1975

Electron Impact Autoionization In Heavy Alkali Metals, Kaare J. Nygaard

Physics Faculty Research & Creative Works

Autoionizing levels in cesium, rubidium, and potassium have been studied by electron impact in a crossed-beam apparatus. Comparisons are made with the binary-encounter calculations of Roy and Rai. The effects of autoionization and inner-shell ionization have been overestimated in the theory. © 1975 The American Physical Society.


Horace W. Slocum Journals - Accession 23, Horace W. Slocum Jan 1975

Horace W. Slocum Journals - Accession 23, Horace W. Slocum

Manuscript Collection

The Horace W. Slocum Journals include handwritten and typewritten accounts of Mr. Slocum’s journeys through South Carolina, North Carolina, Pennsylvania, Virginia, New York, Illinois, New Hampshire, and other states in search of rocks and minerals. Of special interest are photographs and maps of geological and mining sites in the typewritten, edited version of the journals. There is also a map index. The journals extend mainly from 1938 to 1956.


Biquadratic Exchange And First-Order Ferromagnetic Phase Transitions, Harry A. Brown Jan 1975

Biquadratic Exchange And First-Order Ferromagnetic Phase Transitions, Harry A. Brown

Physics Faculty Research & Creative Works

We have calculated some properties of a ferromagnet using a Heisenberg Hamiltonian with a biquadratic exchange term added. The constant-coupling approximation was employed. If the strength of the biquadratic exchange relative to the bilinear is given by a dimensionless parameter α, there is a critical value αc at which the phase transition changes character from second order for αα>αc. The spontaneous magnetization, the exchange energy, and the spin-correlation function show discontinuous jumps at α=αc and unstable behavior for α>αc. © 1975 The American Physical Society.


Analogy Between Spinodal Decomposition And Martensitic Transformation, Tetsuro Suzuki, Manfred Wuttig Jan 1975

Analogy Between Spinodal Decomposition And Martensitic Transformation, Tetsuro Suzuki, Manfred Wuttig

Physics Faculty Research & Creative Works

The translation of the theory developed for the spinodal decomposition of a supercooled alloy to the language appropriate for the martensitic transformation is carried out. In the spinodal theory, the stability of the alloy with respect to the composition fluctuation is examined, while in the present theory the stability of the crystal with respect to the shear displacement fluctuation, the transverse phonon, is studied. The analogy to the spinodal theory requires the revival of the strain gradient energy term or the couple stress term, the presence of which has been a subject of controversies for a long time since Laval. …


A High-Power Pulsed Xenon Ion Laser As A Pump Source For A Tunable Dye Laser, Laird D. Schearer Jan 1975

A High-Power Pulsed Xenon Ion Laser As A Pump Source For A Tunable Dye Laser, Laird D. Schearer

Physics Faculty Research & Creative Works

An inexpensive pulsed xenon ion laser with peak power outputs up to 4 kW has been constructed and used as a pump source for a tunable rhodamine 6G dye laser with a 0.25-A bandpass in the yellow-red range of the spectrum. The dye laser is tunable from 5465 to 6300 A. Over 50 W are obtained at the peak of the tuning range. Copyright © 1975 by The Institute of Electrical and Electronics Engineers, Inc.


Excitation Of Atomic Hydrogen To The N=2 States By 15-200-Kev Protons, John T. Park, J. E. Aldag, J. M. George Jan 1975

Excitation Of Atomic Hydrogen To The N=2 States By 15-200-Kev Protons, John T. Park, J. E. Aldag, J. M. George

Physics Faculty Research & Creative Works

Cross sections for the process H+ + H H+ + H* (n=2) are determined from the energy-loss spectra of 15-200-keV protons. After normalization at 200 keV to the Born approximation, the maximum value (1.07 x 10-16 cm2 at 60 keV) lies below close-coupling calculations and above Glauber-approximation calculations. The agreement with low-energy (5-30-keV) data of others is very good. © 1975 The American Physical Society.


Use Of The Psi Technique In Prerequisite Courses, John T. Park, William R. Snow Jan 1975

Use Of The Psi Technique In Prerequisite Courses, John T. Park, William R. Snow

Physics Faculty Research & Creative Works

An engineering physics course, in which the Personalized System of Instruction (PSI) technique has been used, has been designed to meet the requirements that all of a prescribed list of subjects be covered and that the course be completed within a single semester. The course was modified so that it has two levels of mastery for each unit: a passing level and a complete mastery level. All students were required to reach a passing level of mastery on all of the required material. Grades were assigned according to the number of complete mastery level examinations passed. It was found that …


Photoionization Of The 6p32,122 Fine-Structure Levels In Cesium, Kaare J. Nygaard, Robert E. Hebner, James A. Jones, Robert J. Corbin Jan 1975

Photoionization Of The 6p32,122 Fine-Structure Levels In Cesium, Kaare J. Nygaard, Robert E. Hebner, James A. Jones, Robert J. Corbin

Physics Faculty Research & Creative Works

The relative photoionization cross sections for cesium atoms selectively excited to the 6P32,122 states have been measured in a triple-crossed-beam experiment. A cesium discharge lamp produced resonant wavelengths of 8521 and 8944 for the excitation process. A Hg-Xe lamp combined with a grating monochromator was used for the actual ionization in the wavelength region from 2500 to 5000. Background counts due to photoionization of ground-state cesium atoms and dimers as well as various surface effects were discriminated against by chopping the excitation light source. The data are compared with results from radiative-recombination measurements in which the fine-structure levels are not …


Erratum: Multimedia Dispersion Relation For Surface Electromagnetic Waves. (The Journal Of Chemical Physics (1975) 62 (1674)), C. A. Ward, K. Bhasin, Robert John Bell, Ralph William Alexander, I. Tyler Jan 1975

Erratum: Multimedia Dispersion Relation For Surface Electromagnetic Waves. (The Journal Of Chemical Physics (1975) 62 (1674)), C. A. Ward, K. Bhasin, Robert John Bell, Ralph William Alexander, I. Tyler

Physics Faculty Research & Creative Works

No abstract provided.


Surface Electromagnetic Waves On Layered Systems With Damping, C. A. Ward, Ralph William Alexander, Robert John Bell Jan 1975

Surface Electromagnetic Waves On Layered Systems With Damping, C. A. Ward, Ralph William Alexander, Robert John Bell

Physics Faculty Research & Creative Works

The Dispersion Curves, Propagation Distances, and Poynting Vectors of Surface Electromagnetic Waves Propagating on a System of Cu-Cu2O-Air with Variable Film Thickness Have Been Calculated using the Full Dispersion Realation Including Damping. Double-Dip Structure in the Propagation Distance for Intermediately Thick overlayers, the Shifting of One Dip Below ΣTO, and the Presence of the Other Dip at ΣLO Are Explained in Terms of Features of the Dispersion Curve. the Complete Poynting-Vector Calculations Show that Predictions of Field Bunching at ΣLO Are Probably in Error. © 1975 the American Physical Society.


The Use Of Surface Electromagnetic Waves To Measure Materials Properties, Ralph William Alexander, Robert John Bell Jan 1975

The Use Of Surface Electromagnetic Waves To Measure Materials Properties, Ralph William Alexander, Robert John Bell

Physics Faculty Research & Creative Works

An Elementary Introduction to Surface Electromagnetic Waves (SEW) is Presented. the Emphasis is on Those Features of SEW Which Make Them Useful for Measuring Optical Properties of Thin Layers on Metals. the So-Called Two-Prism Technique for Making Such Measurements is Discussed, Some Preliminary Experimental Results Are Given, and Some Possible Applications Are Presented. © 1975.


Double Reflection Dips From Grating Ruled Semiconductors, L. F. Teng, Ralph William Alexander, Robert John Bell, B. Fischer Jan 1975

Double Reflection Dips From Grating Ruled Semiconductors, L. F. Teng, Ralph William Alexander, Robert John Bell, B. Fischer

Physics Faculty Research & Creative Works

The Double Reflectivity Dips, Previously Observed by Fischer Et Al. and Anderson Et Al., Which Appeared in the Reflection Spectra of Grating Surfaces On, the Te‐doped Semiconductors GaAs and InSb Around Both the Plasmon and Phonon Frequencies Have Been Measured in More Detail. in the Plasmon Region, Several Possible Explanations of the Phenomenon Are Discussed, But the Favored Explanation Involves Surface Damage. a Simple Two‐region Reflectivity Equation Checked with a Rigorous Grating Theory is Proposed and is Shown to Fit the Data Well. Copyright © 1975 WILEY‐VCH Verlag GmbH & Co. KGaA


Millipedes In The Collection Of The Amcs. Iii. Reddellobus Troglovbius, N. Gen., N. Sp., An Unusual Troglobite From Peubla, Mexico, And Other Records Of The Family Spirouolellidae (Order Spirobolida, Class Diplopoda), Nell B. Causey Jan 1975

Millipedes In The Collection Of The Amcs. Iii. Reddellobus Troglovbius, N. Gen., N. Sp., An Unusual Troglobite From Peubla, Mexico, And Other Records Of The Family Spirouolellidae (Order Spirobolida, Class Diplopoda), Nell B. Causey

International Journal of Speleology

During the past several years, members of the Association for Mexican Cave Studies have made some surprising additions to the knowledge of the invertebrate fauna of Mexico. None of their finds is more exciting than the species described here, a millipede much larger than the nearest epigean relative in an order outstanding for its scarcity of troglobitic adaptations. The absence of ocelli and the reduction of body pigment in the known epigean typhlobolellids suggest that they are deep humus dwellers preadapted for cave life.


Eine Neue Discoptila Aus Anatolischen Höhlen (Orthoptera, Gryllidae), Alexi Popov Jan 1975

Eine Neue Discoptila Aus Anatolischen Höhlen (Orthoptera, Gryllidae), Alexi Popov

International Journal of Speleology

A new troglophilous cave-cricket, Discoptila beroni n.sp. is described and figured. It is common in the caves Maara near Mersin and Damlatas near Alanya in South Anatolia. The characteristic features of the males, as well as of the females, by which the new species is distinguished from the other eight species of the genus, all distributed in the Mediterranean, are pointed out. D. beroni n.sp. has already been reported erroneously from the cave Damlatas as D. fragosoi (Bol.) and as D. brevis B.-Bien.


Symposium On Life Histories Of Cave Beetles: An Introduction, Thomas L. Poulson Jan 1975

Symposium On Life Histories Of Cave Beetles: An Introduction, Thomas L. Poulson

International Journal of Speleology

Overview of the six papers presented at the Symposium on Life Histories of Cave Beetles held at the 1973 annual convention of the National Speleological Society at Bloomington in Indiana (USA).


Seasonal Changes In A Population Of Pseudanopthalmus Tenuis (Coleoptera, Carabidae) In Murray Spring Cave, Indiana: A Preliminary Report, James H. Keith Jan 1975

Seasonal Changes In A Population Of Pseudanopthalmus Tenuis (Coleoptera, Carabidae) In Murray Spring Cave, Indiana: A Preliminary Report, James H. Keith

International Journal of Speleology

A study of a population of Pseudanophthalmus tenuis is being conducted in Murray Spring Cave, Orange County, Indiana as one facet of a larger research project encompassing the entire terrestrial community of that cave. Changes in behaviour and abundance determined by census and mark-recapture methods and physiological changes determined from field-collected beetles indicates that these animals exhibit a seasonal reproductive rhythm probably mediated or controlled by winter and spring flooding of the cave.


Interaction Between Competition And Predation In Cave Stream Communities, David C. Culver Jan 1975

Interaction Between Competition And Predation In Cave Stream Communities, David C. Culver

International Journal of Speleology

Predation by salamander larvae (Gyrinophilus porphyriticus) reduces the density of one of its prey (the isopod Asellus recurvatus) but increases the density of the other (the amphipod Crangonyx antennatus in a Virginia cave stream. This happens because predation on the isopod reduces its competitive effect on the amphipod. Both prey populations tend to occur more frequently in refugia when predators are present. In another cave where there are no prey refugia, the predator reduces the density of both species. It appears that it is easier for a predator to invade a community than to reach a stable …


Pseudosinella Styriaca Sp.N (Collembola: Entomobryidae) A New Collembolan Species From The Styrian Cave "Raudner - Höhle" (Austria), Heinz Neuherz, Josef Nosek Jan 1975

Pseudosinella Styriaca Sp.N (Collembola: Entomobryidae) A New Collembolan Species From The Styrian Cave "Raudner - Höhle" (Austria), Heinz Neuherz, Josef Nosek

International Journal of Speleology

Description of a new cavernicolous species of Pseudosinella, P. styriaca. The species was found in the cave “Raudner - Hohle” (Styria, Austria). P. styriaca sp. n. belongs to the Mediterranean group of Pseudosinella.


Sur Les Bathynella De Roumanie: B.(B.) Boteai Serban, B.(B.) Vaducrisensis N.Sp., B.(B.) Plesai Serban Et B.(B.) Motrensis Serban (Bathynbellacea, Bathynellidae) Première Partie, Eugène Serban Jan 1975

Sur Les Bathynella De Roumanie: B.(B.) Boteai Serban, B.(B.) Vaducrisensis N.Sp., B.(B.) Plesai Serban Et B.(B.) Motrensis Serban (Bathynbellacea, Bathynellidae) Première Partie, Eugène Serban

International Journal of Speleology

In the first part of the note we present a minute description of the species B.(B.) boteai Serban, B. (B.) motrensis Serban and B. (B.) plesai Serban. The provisional diagnosis of these species were already published in 1971. A new species B.(B.) vaducrisensis is also described. The genus Bathynella Vejdovsky is now known in the Romanian fauna with 6 species: four of them already mentioned, plus B. (B.) paranatans Serban and B. (B.) scythica Botosaneanu and Damian.


Versuche Zur Erfassung Der Vertikalen Verteilung Von Organismen Und Chemischen Substanzen Im Grundwasser Von Talauen Und Terrassen; Methoden Und Erste Befunde, Siegfried Husmann Jan 1975

Versuche Zur Erfassung Der Vertikalen Verteilung Von Organismen Und Chemischen Substanzen Im Grundwasser Von Talauen Und Terrassen; Methoden Und Erste Befunde, Siegfried Husmann

International Journal of Speleology

In the alluvial ground of the river Fulda valley and in the diluvial terrace of the river Weser assortments of tubes of various lengths were sunk into sandy and gravely underground to bring to light groundwater of different depths. The installation of these groundwater pump stations was effectuated by two different methods: 1. with the aid of an apparatus for bringing down bore-holes, 2. by ramming in the pump tubes with the aid of a pneumatic hammer. The first biological and chemical investigations in these subterranean water research stations indicated that the vertical distribution of groundwater organisms and chemical substances …


Locating The St. Louis Urban Plume At 80 And 120 Km And Some Of Its Characteristics, J. F. Stampfer, J. A. Anderson Jan 1975

Locating The St. Louis Urban Plume At 80 And 120 Km And Some Of Its Characteristics, J. F. Stampfer, J. A. Anderson

Chemistry Faculty Research & Creative Works

The feasibility of locating the urban plume of a moderately large urban area, as far as 120 km downwind, is shown. The method utilizes a single engine aircraft and aerosol instrumentation. A summary of the data obtained from 34 flights, during an 8-month period, is presented and the problems involved in interpreting the data are discussed. These difficulties include nonuniform background levels outside the plume, changing relative humidity, low wind speeds and stable atmospheric layers. The plume was characterized by concentrations of small particles (0.15 < r < 0.3 μm) ca. 1.5 times that in background air and concentrations of large particles (0.3 < r < 1.3 μm) usually greater than twice that in the background. The ratio of the concentrations of small particles to large particles in the plume was about one-half of that in the background. © 1975.


Class Groups Of Real Quadratic Number Fields, Paul B. Massell Jan 1975

Class Groups Of Real Quadratic Number Fields, Paul B. Massell

Dissertations, Theses, and Capstone Projects

No abstract provided.


A Study Of The Effects Of Numerical Error Propagated Through Several Independent Stages: An Electron Optics Simulation., William Donald Webster Jan 1975

A Study Of The Effects Of Numerical Error Propagated Through Several Independent Stages: An Electron Optics Simulation., William Donald Webster

Masters Theses

"Presented is a study, combining numerical methods in a series of stages whereby each stage provides input data to its successor. A model problem from electron optics ii is studied in which a potential field is computed, gradient vectors calculated, and trajectory equations solved. Error effects in each stage is assessed for its influence on the final results of the numerical process mimicking the model problem. Error analysis is given in Appendix A. Finally, the superiority of Spline approximations for estimating derivatives is demonstrated"-- Abstract, p. ii


Reflected Surface Waves From A Vertical Discontinuity., Jesus Manuel Aboud Jan 1975

Reflected Surface Waves From A Vertical Discontinuity., Jesus Manuel Aboud

Masters Theses

"Surface waves generated in the field by small explosions were observed along lines parallel and perpendicular to a vertical discontinuity in a surface layer. Three types of wave particle motion were observed in waves incident on the discontinuity: retrograde, progressive, and shear (SH). Waves of the last two types were intense enough to observe a reflection, permitting calculation of reflection coefficients. The results demonstrate the feasibility of using reflection measurements to locate a discontinuity such as a fault zone"-- Abstract, p. ii