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1997

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High-Resolution Microscopy: Application To Detector Characterization And A New Super-Resolution Technique, Daniel Kavaldjiev Jan 1997

High-Resolution Microscopy: Application To Detector Characterization And A New Super-Resolution Technique, Daniel Kavaldjiev

Theses

The research, presented in this dissertation, consists of two parts. In the first half of the work a novel microscopy method, Frequency-domain Field- confined Scanning Optical Microscopy (FFSOM), capable of a resolution below the classical diffraction limit, is introduced. An experimental verification in the case of fluorescence microscopy is also presented, suggesting the biological microscopy research as an important application field. The second half of the thesis is devoted to an experimental measurement of the subpixel spatial variations in solid-state light detectors, namely in a Charge-Coupled Devices (CCD). A specialized high-resolution scanning optical microscope, is described. With the help of …


A Comparison Of Personality Characteristics Of Male And Female Engineering Students, Erin Beth Williams Jan 1997

A Comparison Of Personality Characteristics Of Male And Female Engineering Students, Erin Beth Williams

All-Inclusive List of Electronic Theses and Dissertations

The purpose of this study was to investigate differences between personality characteristics of female and male freshmen, engineering students. A secondary purpose was to ascertain whether personality characteristics of freshmen, engineering students were different from those of general collegiate students of the same sex. The Millon Index of Personality Styles (MIPS) was administered to a sample of 72 female and 86 male freshmen, engineering students at a private midwestern engineering institution. The MIPS college normative sample of 1,600 college students was used as a comparison group. A total of 24 personality characteristics were assessed in the domains of motivation aims, …


Moisture Gain Of Biscuits In Hermetically-Sealed Packages Versus Non-Hermetically-Sealed Packages, Amran Alabakan Jan 1997

Moisture Gain Of Biscuits In Hermetically-Sealed Packages Versus Non-Hermetically-Sealed Packages, Amran Alabakan

Theses

The objective of this study was to examine the affect of hermetic sealing on extending the shelf life of a biscuit product. Hermetically sealed packages were compared with non-hermetically-sealed packages received from the biscuit manufacturer. The package materials were the same so the only variable was the hermetic integrity of the package. A pressure test was conducted to determine the hermetic integrity of the package samples. The maximum moisture content that the biscuits gained before they were considered spoiled was then determined. Moisture gain of biscuit products kept in a 100% RH environment was monitored by recording the changes in …


On Game Theory And The Law, Kenneth G. Dau-Schmidt, Jeffrey E. Stake, Robert H. Heidt, Eric Rasmusen, Michael Alexeev Jan 1997

On Game Theory And The Law, Kenneth G. Dau-Schmidt, Jeffrey E. Stake, Robert H. Heidt, Eric Rasmusen, Michael Alexeev

Articles by Maurer Faculty

No abstract provided.


Investigation Of The Optical Properties Of Ordered Semiconductor Materials, Jack E. Mccrae Jr. Jan 1997

Investigation Of The Optical Properties Of Ordered Semiconductor Materials, Jack E. Mccrae Jr.

Theses and Dissertations

Optical studies have been conducted upon CdGeAs2 and ZnGeP2, two of the most promising semiconductors being developed for mid-infrared non-linear optics applications. These experiments included photoluminescence (PL) studies of both compounds as well as photoreflectance (PR) measurements upon CdGeAs2. In addition, Hall effect measurements were carried out upon CdGeAs2, to aid in interpretation of the optical data. PL was measured as a function of laser power, sample temperature, and crystal orientation for CdGeAs2. One broad weak peak near 0.38 eV, and another somewhat narrower and often far brighter peak near 0.57 …


Four-Wave Mixing And Optical Phase Conjugation In Vertical Cavity Surface Emitting Devices, Gregory J. Vansuch Jan 1997

Four-Wave Mixing And Optical Phase Conjugation In Vertical Cavity Surface Emitting Devices, Gregory J. Vansuch

Theses and Dissertations

Four-wave mixing (FWM), a nonlinear optical process, was investigated in resonant cavity light emitting diodes (RCLEDs) and vertical cavity surface emitting lasers (VCSELs) below lasing threshold. These semiconductor photonic devices consisted of an optical gain region of quantum wells sandwiched between two distributed Bragg reflector (DBR) mirrors. Pump and probe lasers were injected into the devices to generate FWM. The dependence of FWM on bias current, pump laser power, and spectral and spatial separation between pump and probe lasers was investigated experimentally. A computer model of FWM based on the wave and carrier density equations was developed and agreed well …


Incentives, Information, And Winner's Curse In Construction Industry Bidding, Gerald H. Williams, Timothy R. Anderson Jan 1997

Incentives, Information, And Winner's Curse In Construction Industry Bidding, Gerald H. Williams, Timothy R. Anderson

Engineering and Technology Management Faculty Publications and Presentations

This paper investigates the relationship between incentives, information and winner's curse in the bidding for construction industry contracts. The approach uses both simple Monte Carlo simulations and bidding experiments to show the effects of changing levels of information (in terms of variance) and incentive (in terms of risk share) on the winner's curse.


A New Measure Of Baseball Batters Using Dea, Timothy R. Anderson, Gunter P. Sharp Jan 1997

A New Measure Of Baseball Batters Using Dea, Timothy R. Anderson, Gunter P. Sharp

Engineering and Technology Management Faculty Publications and Presentations

Data Envelopment Analysis (DEA) is used to create an alternative to traditional batting statistics called the Composite Batter Index (CBI). Advantages of CBI over traditional statistics include the fact that players are judged on the basis of what they accomplish relative to other players and that it automatically accounts for changing conditions of the game that raise or lower batting statistics. Historical results are examined to show how the industry of baseball batting has matured and potential uses of CBI are discussed. The application of baseball suggests that random variation may have an effect on CBI. We investigated this effect …


A Strategy For Monitoring Glaciers, Andrew G. Fountain, Robert M. Krimmel, Dennis C. Trabant Jan 1997

A Strategy For Monitoring Glaciers, Andrew G. Fountain, Robert M. Krimmel, Dennis C. Trabant

Geography Faculty Publications and Presentations

Glaciers are important features in the hydrologic cycle and affect the volume, variability, and water quality of runoff. Assessing and predicting the effect of glaciers on water resources require a monitoring program to provide basic data for this understanding. The monitoring program of the U.S. Geological Survey employs a nested approach whereby an intensively studied glacier is surrounded by less intensively studied glaciers and those monitored solely by remote sensing. Ideally, each glacierized region of the United States would have such a network of glaciers. The intensively studied glacier provides a detailed understanding of the physical processes and their temporal …


Global Attractors From The Explosion Of Singular Cycles, Carlos Arnoldo Morales, Maria José Pacífico, Enrique Ramiro Pujals Jan 1997

Global Attractors From The Explosion Of Singular Cycles, Carlos Arnoldo Morales, Maria José Pacífico, Enrique Ramiro Pujals

Publications and Research

Abstract:

In this paper we announce recent results on the existence and bifurcations of hyperbolic systems leading to non-hyperbolic global attractors.

Résumé:

Nous présentons dans cette Note des résultats récents concernant l’existence et les bifurcations d’un nouvel attracteur global chaotique.


Potential For Coastal Flooding Due To Coseismic Subsidence In The Central Cascadia Margin, Elson T. Barnett Jan 1997

Potential For Coastal Flooding Due To Coseismic Subsidence In The Central Cascadia Margin, Elson T. Barnett

Dissertations and Theses

Interpretations made from compilation of existing core and cutbank data for Oregon and Washington are used to evaluate the potential flooding impact from regional coseismic subsidence. Estimates of regional subsidence are based on tidal level indicators including plant macrofossils, peat development, and diatoms. A compilation of existing late Holocene stratigraphic records shows multiple burial events in all bays of Oregon, however some coastal sites in central Oregon show continuous submergence. Tests of tidal level indicators using modern Cascadia wetlands indicate that paleosubsidence can be estimated to 0.0 ± 0.5m, 1.0 ±0.5m, and 2 m ± 0.5m. An AMS date from …


Simulating Migration Of Contaminated Sediments In The Lower Columbia Slough System, Min Chen Jan 1997

Simulating Migration Of Contaminated Sediments In The Lower Columbia Slough System, Min Chen

Dissertations and Theses

Recent screening-level risk assessment of Slough sediments initiated by the City of Portland identified five contaminated areas in the Slough as posing the greatest potentially significant risks to human health. These five areas were recommended for accelerated remedial action.

But one question remains, does the sediment contamination at these hot spots change over time in response to the changing Slough hydrodynamics? Specifically, will the contamination move or spread even before remedial action is taken? Will they still be there by the time when potential remedial action is taken? Will any new hot spots be created in response to nonuniform transient …


General Remarks On Spectral Entropy Vs. Statistical Entropy, John D. Ramshaw Jan 1997

General Remarks On Spectral Entropy Vs. Statistical Entropy, John D. Ramshaw

Physics Faculty Publications and Presentations

Crepeau and Herzel [1] (CH) have recently compared the spectral entropy of Powell and Percival [2] with the standard statistical (Boltzmann-Gibbs-Shannon) entropy in three simple physical systems. Here we compare and contrast these two entropies in a more general way by considering their values for an arbitrary stationary process X(t).


Optical Imaging Of Carrier Dynamics In Silicon With Subwavelength Resolution, Andres H. La Rosa, B. I. Yakobson, H. D. Hallen Jan 1997

Optical Imaging Of Carrier Dynamics In Silicon With Subwavelength Resolution, Andres H. La Rosa, B. I. Yakobson, H. D. Hallen

Physics Faculty Publications and Presentations

Characteristic rate variations of carrier processes are imaged using near-field scanning optical microscopy. We couple both a visible pump and an infrared probe light through a subwavelength aperture to investigate the interband recombination and intraband diffusion of excess carriers in oxidized silicon. Typical values of the locally measured life time constants agree well with those obtained by conventional space-averaged techniques. Moreover, the images locate defects, reveal variations, and can map the regions in which a recombination process is active.


Some Applications Of Generalized Ffts, Daniel N. Rockmore Jan 1997

Some Applications Of Generalized Ffts, Daniel N. Rockmore

Dartmouth Scholarship

Generalized FFTs are efficient algorithms for computing a Fourier transform of a function defined on finite group, or a bandlimited function defined on a compact group. The development of such algorithms has been accompanied and motivated by a growing number of both potential and realized applications. This paper will attempt to survey some of these applications. Appendices include some more detailed examples.


Matching Numerical Simulations To Continuum Field Theories: A Lattice Renormalization Study, J Borrill, M. Gleiser Jan 1997

Matching Numerical Simulations To Continuum Field Theories: A Lattice Renormalization Study, J Borrill, M. Gleiser

Dartmouth Scholarship

The study of nonlinear phenomena in systems with many degrees of freedom often relies on complex numerical simulations. In trying to model realistic situations, these systems may be coupled to an external environment which drives their dynamics. For nonlinear field theories coupled to thermal (or quantum) baths, discrete lattice formulations must be dealt with extreme care if the results of the simulations are to be interpreted in the continuum limit. Using techniques from renormalization theory, a self-consistent method is presented to match lattice results to continuum models. As an application, symmetry restoration in ϕ4 models is investigated.


The Rosat Hri X-Ray Survey Of The Cygnus Loop, N. A. Levenson, J R. Graham, B. Aschenbach, W. P. Blair, W. Brinkmann, J. U. Busser, R. Egger, R. A. Fesen, J. J. Hester, S. M. Kahn, R. I. Klein, C. F. Mckee, R. Petre, R. Pisarski, J. C. Raymond, S. L. Snowden Jan 1997

The Rosat Hri X-Ray Survey Of The Cygnus Loop, N. A. Levenson, J R. Graham, B. Aschenbach, W. P. Blair, W. Brinkmann, J. U. Busser, R. Egger, R. A. Fesen, J. J. Hester, S. M. Kahn, R. I. Klein, C. F. Mckee, R. Petre, R. Pisarski, J. C. Raymond, S. L. Snowden

Dartmouth Scholarship

We describe and report progress on the joint U.S. and German campaign to map the X-ray emission from the entire Cygnus Loop supernova remnant with the ROSAT High Resolution Imager. The Cygnus Loop is the prototype for a supernova remnant that is dominated by interactions with the interstellar medium and supplies fundamental physical information on this basic mechanism for shaping the interstellar medium. The global view that these high-resolution observations provide emphasizes the inhomogeneity of the interstellar medium and the pivotal nature of cloud-blast wave interactions in determining the X-ray morphology of the supernova remnant. While investigating the details of …


Resolution Of Local Inconsistency In Identification, Douglas Ray Anderson, Martin Zwick Jan 1997

Resolution Of Local Inconsistency In Identification, Douglas Ray Anderson, Martin Zwick

Complex Systems Faculty Publications and Presentations

This paper reports an algorithm for the resolution of local inconsistency in information-theoretic identification. This problem was first pointed out by Klir as an important research area in reconstructability analysis. Local inconsistency commonly arises when an attempt is made to integrate multiple data sources, i.e., contingency tables, which have differing common margins. For example, if one ha)s an AB table and a BC table, the B margins obtained from the two tables may disagree. If the disagreement can be assigned to sampling error, then one can arrive at a compromise B margin, adjust the original AB and BC tables to …


Faculty Senate Monthly Packet January 1997, Portland State University Faculty Senate Jan 1997

Faculty Senate Monthly Packet January 1997, Portland State University Faculty Senate

Faculty Senate Monthly Packets

The January 1997 Monthly packet includes the January agenda and appendices and the Faculty Senate minutes and attachments from the meeting held December 1996.


Microlanguages For Operating System Specialization, Calton Pu, Andrew P. Black, Crispin Cowan, Jonathan Walpole, Charles Consel Jan 1997

Microlanguages For Operating System Specialization, Calton Pu, Andrew P. Black, Crispin Cowan, Jonathan Walpole, Charles Consel

Computer Science Faculty Publications and Presentations

Specialization is a technique that has the potential to provide operating system clients with the performance and functionality that they need, while still retaining the advantages of a simple generic code base for the operating system maintainer. However, at present the specialization process is labor-intensive and requires the knowledge of an expert in the domain of application behavior. In order to realize the full advantages of specialization, we believe that the process must be automated. This means building tools for specialization, and also making the domain knowledge explicit in some form or other. A specialization toolkit has been developed jointly …


Response Surface Methodology: An Analytical Method For Locating Migrated Contaminant Sources, Orlando J. Dona Jr. Jan 1997

Response Surface Methodology: An Analytical Method For Locating Migrated Contaminant Sources, Orlando J. Dona Jr.

Theses and Dissertations

The use and storage of hazardous chemicals at U.S. military facilities often adversely affect the groundwater when contaminants infiltrate the subsurface as a result of leaks and accidental spills. These contaminants, if not located and remediated in a relatively short time, may move and settle unpredictably, essentially creating a source some distance from the original leak or spill. An example of this phenomenon is found with migrating dense nonaqueous phase liquid (DNAPL) contaminants. Although various methods for estimating the present day locations of these migrated contaminants are in use, accurately pinpointing the source of contaminants remains a difficult problem in …


Spectroscopic And Kinetic Studies Of Bismuth Dimers, Robert Eugene Frankin Jan 1997

Spectroscopic And Kinetic Studies Of Bismuth Dimers, Robert Eugene Frankin

Theses and Dissertations

The spectroscopy of high rotational levels (J ≤ 211) in Bi2 X(Og+) and A(Ou+) was investigated for 2≤v"≤5 and 0≤v'≤4 by observing total fluorescence from laser excitation. Dunham coefficients were derived that fit all observed rotational lines to within 0.01 cm-1. Franck-Condon factors were calculated and experimentally verified for transitions originating from the initially populated levels 0≤v'≤5. Vibrational energy transfer upon collision with rare gas collision partners was investigated for the low-lying vibrational levels of the A-state using spectrally resolved, continuous wave laser induced fluorescence. Vibrational transfer was adequately modeled by …


Efficient Implementation Of Image Compression-Postprocessing Algorithm Using A Digital Signal Processor, Nadir Sinaceur Jan 1997

Efficient Implementation Of Image Compression-Postprocessing Algorithm Using A Digital Signal Processor, Nadir Sinaceur

Dissertations and Theses

In this thesis, an attempt has been made to develop a fast way to implement a post-processing algorithm for image compression. All the previous tests for this postprocessing algorithm, which we will present, have been only software based and did not consider the time parameter.

For this purpose a new algorithm is used to compute the 2-D DCT transform. This change made the process a lot faster on a Spare 5 workstation. We have then decided to further increase the speed of the post-processing scheme by implementing it on the ADSP21020 chip.

The results show that such a chip can …


Extending And Exploring Students' Problem Solving Via Problem Posing, Elena N. Stoyanova Jan 1997

Extending And Exploring Students' Problem Solving Via Problem Posing, Elena N. Stoyanova

Theses: Doctorates and Masters

Despite the fact that problem posing has been recommended as a useful mathematical activity in the curriculum documents of several countries, research about the types of problem-posing situations in which students could be involved, and about the effects of these problem-posing activities on students' mathematical performance is limited. The application of problem posing in school mathematics has been hindered by the absence of a framework which links problem posing, problem solving and mathematics curricula


Webassess, Justin Anthony Brown Jan 1997

Webassess, Justin Anthony Brown

Theses : Honours

This project and research has resulted in the development of a World Wide Web (WWW) based testing system. WEBassess can be accessed and used from any point in the world that has a connection to the WWW. The WEBassess system allows for the creation and completion of tests through the WWW interface. Scoring and feedback of submitted tests is completely automated, allowing students to see their test result immediately, including visual indicators for correct and incorrect answers. These test results may then be viewed by academic staff, showing complete test details, such as unit code, test title, score, percentage, date …


A Descriptive Study Of The Use Of A Problem Solving Heuristic In A Cooperative Small Group Setting, Kim Pitts-Hill Jan 1997

A Descriptive Study Of The Use Of A Problem Solving Heuristic In A Cooperative Small Group Setting, Kim Pitts-Hill

Theses: Doctorates and Masters

This research is in the area of small group cooperative learning. Cooperative learning groups range in size from two to eight students and have, as a central focus, students working collaboratively to achieve common goals. Generally members of the group have their individual a:1d group responsibilities and the task is usually not completed unless every member participates in the activity. Exponents of cooperative learning methods claim that student achievement and understanding of the content is equal if not better than learning under traditional methods due to increased social skills, improved self esteem, and the reduced effects of ethnic differences or …


Teaching Visual Arts Through Distance Education : An Evaluation Of The Program Anyone Can Draw, Jane Whelan Jan 1997

Teaching Visual Arts Through Distance Education : An Evaluation Of The Program Anyone Can Draw, Jane Whelan

Theses: Doctorates and Masters

The problem under investigation is concerned with the teaching of drawing through distance education. Traditionally drawing has occupied a central position in visual art teaching and learning and is still regarded as a significant area of visual arts education. In the visual arts curriculum of Western Australia, drawing, which is included in the broader term visual inquiry, is regarded as the foundation for studio practice. It is therefore appropriate to include drawing as part of every visual arts teaching program. The correspondence mode of teaching, which has a text-base, is a more formal style of teaching art than the responsive …


Critical Competencies For Effective Teaching : Perceptions Of Home Economics Teachers, Esthery D. Kunkwenzu Jan 1997

Critical Competencies For Effective Teaching : Perceptions Of Home Economics Teachers, Esthery D. Kunkwenzu

Theses: Doctorates and Masters

Home economics is a multi-faceted, inter-disciplinary, integrated field of study drawing from a multitude of disciplines including sociology, psychology, anthropology, chemistry, physics, architecture and the arts (Henry, 1995). As a school subject, home economics in Malawi is taught at primary school, secondary school as well as at university level. This study explores home economics teachers' perceptions of competencies critical for teaching the subject. Data was collected from secondary school home economics teachers in Malawi. The study is a qualitative investigation of how experienced teachers describe effective teaching of the integrated home economics syllabus, and what they perceive as critical competencies …


A Simple Scenario For Stygobitization In Stenobermuda Schultz, 1978 (Isopoda Asellota Stenetriidae), With Description Of A New Species From Andros Island, Bahamas, Lazare Botosaneanu, Thomas M. Iliffe Jan 1997

A Simple Scenario For Stygobitization In Stenobermuda Schultz, 1978 (Isopoda Asellota Stenetriidae), With Description Of A New Species From Andros Island, Bahamas, Lazare Botosaneanu, Thomas M. Iliffe

International Journal of Speleology

Description of a new stygobitic and troglomorphic species of Stenobermuda from a Blue Hole in the Bahamas, is an opportunity for speculation about hypogean colonization by this and by another cave-dwelling species from Bermuda, starting from populations of a widely distributed Western Atlantic shallow water marine species.


Les Deux Faces De La Pensée De E. A. Martel, Jacques Choppy Jan 1997

Les Deux Faces De La Pensée De E. A. Martel, Jacques Choppy

International Journal of Speleology

Réunion de textes de Martel: 1 - Extraits du Nouveau Traité des Eaux Souterraines (1921), donnant l’essentiel de la pensée de l’auteur sur l’hydraulique et la morphologie du karst. 2 - En opposition à cette vision, rappelée de nombreuses fois par l’auteur, extraits de diverses publications (de 1894 à 1930), admettant qu’un fonctionnement en régime noyé était possible: Martel est donc l’un des tout premiers ayant observé des formes de creusement en régime noyé, et les ayant interprétées comme telles.