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Theses/Dissertations

1991

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Articles 181 - 210 of 213

Full-Text Articles in Physical Sciences and Mathematics

Nuclear Magnetic Resonance Studies Of Amorphous Nickel-Zirconium Hydrides, Harris Clarence Hoke Jr. Jan 1991

Nuclear Magnetic Resonance Studies Of Amorphous Nickel-Zirconium Hydrides, Harris Clarence Hoke Jr.

Dissertations, Theses, and Masters Projects

This research deals with one aspect of the scientific field of hydrogen in metals. The study of hydrogen in metals is technologically important for many reasons, among them is the use of hydrogen in metals to store energy. Hydrogen related energy technology is particularly attractive because hydrogen can be extracted from water, our most abundant resource, and can be used without any pollution. Metal hydrides may one day be widely used for automotive propulsion in cars, in batteries, and many other energy conversion devices. Amorphous NiZr is particularly interesting for hydrogen storage because high concentrations of hydrogen can be sorbed …


Causal Reasoning About Distributed Programs, William Samuel Lloyd Jan 1991

Causal Reasoning About Distributed Programs, William Samuel Lloyd

Dissertations, Theses, and Masters Projects

We present an integrated approach to the specification, verification and testing of distributed programs. We show how "global" properties defined by transition axiom specifications can be interpreted as definitions of causal relationships between process states. We explain why reasoning about causal rather than global relationships yields a clearer picture of distributed processing.;We present a proof system for showing the partial correctness of CSP programs that places strict restrictions on assertions. It admits no global assertions. A process annotation may reference only local state. Glue predicates relate pairs of process states at points of interprocess communication. No assertion references auxiliary variables; …


Nutrient Standing Stocks And Partitioning In A Forested Coastal Plain Watershed: Groundwater, Stream And Marsh Creek, Sandra A. Hartenstine Jan 1991

Nutrient Standing Stocks And Partitioning In A Forested Coastal Plain Watershed: Groundwater, Stream And Marsh Creek, Sandra A. Hartenstine

Dissertations, Theses, and Masters Projects

No abstract provided.


Classification Of Newborns Based On Maturity Rating And Intrauterine Growth At The Medical College Of Virginia Hospitals, Lydia Holmes Sund Jan 1991

Classification Of Newborns Based On Maturity Rating And Intrauterine Growth At The Medical College Of Virginia Hospitals, Lydia Holmes Sund

Theses and Dissertations

Nurses at the Medical College of Virginia Hospitals (MCVH) in Richmond, Virginia, use the Newborn Maturity Rating and Classification Tool to identify high risk infants. An estimate of gestational age is made and using this estimate, weight, length, and head circumference measurements are plotted on graphs on the tool to determine if the infant achieves intrauterine growth smaller, larger or equal to gestational age.

The data used to generate the graphs on the Newborn Maturity Rating and Classification Tool were collected in Colorado during the 1950's. Two nurses at MCVH questioned the use of these graphs. They wanted to know …


The Problem Of Mutual Exclusion: A New Distributed Solution, Rajeev Chawla Jan 1991

The Problem Of Mutual Exclusion: A New Distributed Solution, Rajeev Chawla

Theses and Dissertations

In both centralized and distributed systems, processes cooperate and compete with each other to access the system resources. Some of these resources must be used exclusively. It is then required that only one process access the shared resource at a given time. This is referred to as the problem of mutual exclusion. Several synchronization mechanisms have been proposed to solve this problem. In this thesis, an effort has been made to compile most of the existing mutual exclusion solutions for both shared memory and message-passing based systems. A new distributed algorithm, which uses a dynamic information structure, is presented to …


Dielectric Monitoring Of The Chemical, Rheological, And Morphological Changes Incurred During Cure Of Epoxide-Amine Systems, Dara Elyn Levy Jan 1991

Dielectric Monitoring Of The Chemical, Rheological, And Morphological Changes Incurred During Cure Of Epoxide-Amine Systems, Dara Elyn Levy

Dissertations, Theses, and Masters Projects

No abstract provided.


Reactions Of Di-(1-Naphthyl) Diazomethane With Beta-Cyclodextrin, Margaret Frances Cabell Jan 1991

Reactions Of Di-(1-Naphthyl) Diazomethane With Beta-Cyclodextrin, Margaret Frances Cabell

Dissertations, Theses, and Masters Projects

No abstract provided.


Preparation And Characterization Of (E)-1-Alkenylboranes And(E)-1-Alkenylboronates An Investigation Of Borane/Nitrone Reactions, Philip Louis Smith Jan 1991

Preparation And Characterization Of (E)-1-Alkenylboranes And(E)-1-Alkenylboronates An Investigation Of Borane/Nitrone Reactions, Philip Louis Smith

Dissertations, Theses, and Masters Projects

No abstract provided.


Limnology Of Two New Lakes, Mount St. Helens, Wa, Valerie Jean Kelly Jan 1991

Limnology Of Two New Lakes, Mount St. Helens, Wa, Valerie Jean Kelly

Dissertations and Theses

Coldwater Lake and Castle Lake are two new lakes which were formed in the aftermath of the volcanic eruption of Mount St . Helens, WA in May, 1980. This research describes the limnology of these lakes ten years later, and includes physical, chemical, and biological parameters. The two lakes are compared and contrasted. Previous research on the eruption and its aftermath, as well as earlier studies of the lakes are described.


Evaluation Of Scavenger Gases In A Helium Discharge Detector, Sandra Lynn Poteat Jan 1991

Evaluation Of Scavenger Gases In A Helium Discharge Detector, Sandra Lynn Poteat

Dissertations, Theses, and Masters Projects

No abstract provided.


Error Flow In Computer Programs, Branson Wayne Murrill Jan 1991

Error Flow In Computer Programs, Branson Wayne Murrill

Dissertations, Theses, and Masters Projects

White box program analysis has been applied to program testing for some time, but this analysis is primarily grounded in program syntax, while errors arise from incorrect program semantics. We introduce a semantically-based technique called error flow analysis, which is used to investigate the behavior of a program at the level of data state transitions. Error flow analysis is based on a model of program execution as a composition of functions that each map a prior data state into a subsequent data state. According to the fault/failure model, failure occurs when a fault causes an infection in the data state …


Stock Enhancement Of Caribbean Spiny Lobster, Panulirus Argus Latrielle, Using Artificial Shelters: Patterns Of Survival And Dynamics Of Shelter Selection, David Bryan Eggleston Jan 1991

Stock Enhancement Of Caribbean Spiny Lobster, Panulirus Argus Latrielle, Using Artificial Shelters: Patterns Of Survival And Dynamics Of Shelter Selection, David Bryan Eggleston

Dissertations, Theses, and Masters Projects

Field tethering experiments in seagrass beds of Bahia de la Ascension, Mexico examined the impact of different-sized artificial shelters upon survival of three juvenile size-classes of the Caribbean spiny lobster, Panulirus argus. The artificial shelters were concrete structures (casitas) that simulate lobster dens. In the tethering experiments, spiny lobster survival was generally higher in smaller than larger casitas, though the effect depended upon the relationship between lobster and shelter size. Thus, spiny lobster survival depends not only upon the availability of shelter, but also on the scaling between shelter size and lobster size. These results suggest that placement of appropriately-scaled …


Comparative Ecology, Morphology, And Population Genetics Of Black Triggerfish, Melichthys Niger, Kathryn D. Kavanagh Jan 1991

Comparative Ecology, Morphology, And Population Genetics Of Black Triggerfish, Melichthys Niger, Kathryn D. Kavanagh

Dissertations, Theses, and Masters Projects

No abstract provided.


Modeling Sediment Resuspension In Lower Chesapeake Bay, Deborah L. Linden Jan 1991

Modeling Sediment Resuspension In Lower Chesapeake Bay, Deborah L. Linden

Dissertations, Theses, and Masters Projects

No abstract provided.


Food And Feeding Of Northern Bluefin Tuna (Thunnus Thynnus) And Yellowfin Tuna (Thunnus Albarcares): A Comparative Study Of The Food And Feeding Habits Of The Northern Bluefin Tuna Off The Coast Of Virginia, Charles Gilbert Barr Jan 1991

Food And Feeding Of Northern Bluefin Tuna (Thunnus Thynnus) And Yellowfin Tuna (Thunnus Albarcares): A Comparative Study Of The Food And Feeding Habits Of The Northern Bluefin Tuna Off The Coast Of Virginia, Charles Gilbert Barr

Dissertations, Theses, and Masters Projects

No abstract provided.


Ecology Of Estuarine Fish Assemblages In Patos Lagoon, Brazil (32 Degrees S), And York River, Usa (37 Degrees N), With Review Of Zoogeography Of Fishes In Western Atlantic Warm-Temperate And Tropical Estuaries, Joao P. Vieira Jan 1991

Ecology Of Estuarine Fish Assemblages In Patos Lagoon, Brazil (32 Degrees S), And York River, Usa (37 Degrees N), With Review Of Zoogeography Of Fishes In Western Atlantic Warm-Temperate And Tropical Estuaries, Joao P. Vieira

Dissertations, Theses, and Masters Projects

The first two chapters of this study examine faunal composition and latitudinal patterns in diversity of fishes in warm-temperate and tropical estuarine waters of the western Atlantic from La Plata River (35&\sp\circ&S), Argentina, to Chesapeake Bay (37&\sp\circ&N), USA (33 faunal reports). Species distributions generally corresponded with previously recognized marine zoogeographic regions, and cluster analyses also showed that faunal similarity among estuarine sampling sites was related to the type of sampling gear used and to the type of habitat that was sampled in each estuary. The total number of fish species reported is positively related to the size of the area …


The Invention Of The Transistor, Bret E. Crawford Jan 1991

The Invention Of The Transistor, Bret E. Crawford

Graduate College Dissertations and Theses

Julius E. Lilienfeld filed for patents for three different designs for solid-state amplifying devices between 1926 and 1928, well before Bell Lab's discovery of the point-contact transistor in 1948. The American Physical Society named a prize in honor of Lilienfeld after receiving a substantial sum of money in 1982 from the will of his wife, Beatrice Lilienfeld, who believed her husband had not received sufficient credit for his scientific contributions. In order to investigate Lilienfeld's contribution to early efforts to replace the vacuum triode, we present the history surrounding these efforts, contributions and limitations of Lilienfeld's work, and details of …


Determination Of Morphologic And Volumetric Change, Peyto Glacier, Alberta, 1966-1989, Peter J. Glenday Jan 1991

Determination Of Morphologic And Volumetric Change, Peyto Glacier, Alberta, 1966-1989, Peter J. Glenday

Theses and Dissertations (Comprehensive)

During the summer months of July and August 1989, approximately 23 years after a photogrammetric survey on August 22, 1966, Peyto Glacier, a glacier selected for study during the International Hydrologic Decade (IHD) 1965-74, was re-surveyed using terrestrial geodetic surveying techniques. The volumetric and morphologic change of Peyto Glacier, Alberta from 1966 to 1989 is estimated through a combined application of digital cartometry, digital geodetic survey and Triangulated Irregular Network (TIN) digital terrain modeling and analysis. Changes in glacial volume, areal extent, teriminus position, percentage basin glaciation, slope, and aspect for the 23 year interval are shown. Additionally, a 1:10000 …


Spatial And Temporal Distribution Of Hydrogen Peroxide In The Equatorial Pacific Ocean, Renee Blanchard Jan 1991

Spatial And Temporal Distribution Of Hydrogen Peroxide In The Equatorial Pacific Ocean, Renee Blanchard

Honors Theses

The concentration of hydrogen peroxide in the Equatorial Pacific was determined fluorometrically using the horseradish peroxidase catalyzed dimerization of (p-hydroxyphenyl)acetic acid. Vertical profiles were obtained between 9 ON and 3 oS on a longitudinal transect along 140 oW during June and July of 1990 on the RN Wecoma. Peroxide concentrations ranged from 25-80 nmol/L at the surface and decreased to the detection limit of 1 nmol/L at a depth of about 200 meters. Diel variations of hydrogen peroxide in the surface waters were observed over the period of 8 days. The variation in surface concentration may be attributed to the …


Interpretation Of The Thermal Behavior Of Groundwater In An Alluvial Terrace : Bonneville Dam, Columbia Gorge, Oregon, Richard Stephen Malin Jan 1991

Interpretation Of The Thermal Behavior Of Groundwater In An Alluvial Terrace : Bonneville Dam, Columbia Gorge, Oregon, Richard Stephen Malin

Dissertations and Theses

Groundwater temperature data, collected at an alluvial terrace located on the Oregon shore of the Columbia River downstream from Bonneville Darn, was analyzed in order to characterize and formulate a conceptual model of the thermal data for the groundwater system in the terrace. There is concern that an unlined entrance channel for a new navigation lock, to be located down the middle of the terrace, will widen the range of temperatures in the fish hatchery-groundwater supply. The analysis of temperature behavior in the terrace supports the hydraulic observations derived from analysis of pump test data, but with greater definition of …


Transient Heat Transfer, Eric Roth Jan 1991

Transient Heat Transfer, Eric Roth

Dissertations and Theses

With the advent of the new high Tc superconductors, liquid nitrogen will be one of the preferred cryogens used to cool these materials. Consequently, a more thorough understanding of the heat transfer characteristics of liquid nitrogen is required. In our investigations we examine the transient heating characteristics of liquid nitrogen to states of nucleate and film boiling under different liquid flow conditions. Using a platinum hot wire technique, it is verified that there is a premature transition to film boiling in the transient case at power levels significantly lower than under steady state nucleate boiling conditions. It is also shown …


An Analysis And Implementation Of Linear Derivation Strategies, Winston M. Tabada Jan 1991

An Analysis And Implementation Of Linear Derivation Strategies, Winston M. Tabada

Theses: Doctorates and Masters

This study examines the efficacy of six linear derivation strategies: (i) s-linear resolution, (ii) the ME procedure; (iii) t-linear resolution, (iv) SL -resolution, (v) the GC procedure, and (vi) SLM. The analysis is focused on the different restrictions and operations employed in each derivation strategy. The selection function, restrictive ancestor resolution, compulsory ancestor resolution on literals having atoms which are or become identical, compulsory merging operations, reuse of truncated literals, spreading of FALSE literals, no-tautologies resection, no two non-B-literals having identical atoms restriction, and the use of semantic information to trim irrelevant derivations from the search tree are the major …


Sediment Budget For The Grouse Creek Basin, Humboldt County, California, Mary A. Raines Jan 1991

Sediment Budget For The Grouse Creek Basin, Humboldt County, California, Mary A. Raines

WWU Graduate School Collection

A sediment budget constructed for the Grouse Creek basin in northern California provides information on the sources and timing of sediment production to aid land managers in understanding the effects of logging impacts in a sensitive watershed. The sediment budget yields a sediment production rate of 1,750 t/km2/yr for a 29-year period. This rate is among the highest for such disturbed forested basins in the Pacific Northwest. Approximately 40 percent of the Grouse Creek basin, which is bisected by regional structural features that have created zones of weak and altered rock, has been logged in the last 35 …


Fabric Study And Structural History Of Deformed Plutonic And Metamorphic Rocks In The Holden Area, North Cascades, Washington, Gary K. Hurban Jan 1991

Fabric Study And Structural History Of Deformed Plutonic And Metamorphic Rocks In The Holden Area, North Cascades, Washington, Gary K. Hurban

WWU Graduate School Collection

The Holden area, in the Crystalline Core of the North Cascades, contains deformed and undeformed plutons ranging from Triassic to Eocene in age.

Two deformational styles have been identified in the Holden area. Contractional deformation is indicated by steeply-plunging, down-dip, mineral and stretching lineations in the syn-tectonic Seven Fingered Jack pluton (estimated midLate Cretaceous), and in the pre-tectonic Dumbell Mountain pluton (220 Ma), associated with apparent flattened fabrics. Strike-slip shear deformation is represented by gently-plunging to subhorizontal, strike-parallel mineral and stretching lineations, which are commonly associated with constricted fabrics. These fabrics occur prominently in the Dumbell Mountain pluton, and crosscut …


Integration Of Abductive And Deductive Inference Diagnosis Model And Its Application In Intelligent Tutoring System, Jingying Zhang Jan 1991

Integration Of Abductive And Deductive Inference Diagnosis Model And Its Application In Intelligent Tutoring System, Jingying Zhang

Computer Science Theses & Dissertations

This dissertation presents a diagnosis model, Integration of Abductive and Deductive Inference diagnosis model (IADI), in the light of the cognitive processes of human diagnosticians. In contrast with other diagnosis models, that are based on enumerating, tracking and classifying approaches, the IADI diagnosis model relies on different inferences to solve the diagnosis problems. Studies on a human diagnosticians' process show that a diagnosis process actually is a hypothesizing process followed by a verification process. The IADI diagnosis model integrates abduction and deduction to simulate these processes. The abductive inference captures the plausible features of this hypothesizing process while the deductive …


A Geophysical And Geological Study Of The Farmville Triassic Basin, Charles G. James Jr. Jan 1991

A Geophysical And Geological Study Of The Farmville Triassic Basin, Charles G. James Jr.

OES Theses and Dissertations

The Farmville basin is one of many Triassic basins which are found along the eastern coast of North America, and is the largest of the central string of basins in Virginia. Meta-volcanic and metasedimentary rocks of the Chopawamsic Formation, as well as felsic intrusives are the primary lithologies surrounding the basin. A detailed gravity survey was conducted along six roads that trend approximately NW-SE, across the basin. Geologic, gravity, magnetic, and radiometric data were used to develop a kinematic model. Gravity anomalies were isolated using two-dimensional harmonic analysis methods to isolate the local, and regional anomalies. This analysis indicates that …


Estimation In A Marked Poisson Error Recapture Model Of Software Reliability, Rajan Gupta Jan 1991

Estimation In A Marked Poisson Error Recapture Model Of Software Reliability, Rajan Gupta

Mathematics & Statistics Theses & Dissertations

Nayak's (1988) model for the detection, removal, and recapture of the errors in a computer program is extended to a larger family of models in which the probabilities that the successive programs produce errors are described by the tail probabilities of discrete distribution on the positive integers. Confidence limits are derived for the probability that the final program produces errors. A comparison of the asymptotic variances of parameter estimates given by the error recapture and by the repetitive-run procedure of Nagel, Scholz, and Skrivan (1982) is made to determine which of these procedures efficiently uses the test time.


A Detailed Gravity Study Over A Known Devonian Carbonate Buildup: The Shell Golden Reef, Northwestern North Dakota, Stephen M. Braun Jan 1991

A Detailed Gravity Study Over A Known Devonian Carbonate Buildup: The Shell Golden Reef, Northwestern North Dakota, Stephen M. Braun

Theses and Dissertations

A detailed gravity study was conducted over the Shell Golden reef in the northwestern North Dakota portion of the Williston Basin. The Shell Golden reef has been previously interpreted to be reefal facies within the Winnipegosis Formation (Devonian) located at a depth of about 2400 meters. Based only on information from wireline logs and core from two boreholes, the Shell Golden well #34X-34 has been previously interpreted as a pinnacle reef with 70 meters of relief and undetermined diameter. The basin regime of the Elk Point shelf created an environment that allowed the growth and development of the Shell Golden …


Erosion Of Fractured Banks, Lake Sakakawea, Western North Dakota, Mark C. Elliott Jan 1991

Erosion Of Fractured Banks, Lake Sakakawea, Western North Dakota, Mark C. Elliott

Theses and Dissertations

Shoreline erosion at Lake Sakakawea has exceeded originally predicted rates. This thesis is a continuation of a project, begun in 1983, to study erosion rates, causes, and prediction; the purpose has been to describe variations in fracture patterns in shoreline banks and assess their affects on erosion rates.

During the first phase of this project (1983-1986), average bank recession was rapid (l.Sm/yr) and factors related to wave action, including fetch, bank orientation, and beach composition, were most important. Since 1986, low lake levels have persisted and wave action has not been a factor; however banks continue to recede, but at …


Tectonic History Of Billings And Southern Mckenzie Counties, Southwestern North Dakota, John J. Crashell Jan 1991

Tectonic History Of Billings And Southern Mckenzie Counties, Southwestern North Dakota, John J. Crashell

Theses and Dissertations

Billings and southern McKenzie Counties contain about 40 active oil and gas fields. In the same area, two major structural highs and several minor ones can be recognized. The first of these, the Billings anticline, extends approximately 60 km (18 mi.) along a north-south line in central Billings County, and is composed of two parallel folds. A second major structure, here termed the Rough Rider anticline, lies west of the Billings anticline, and also extends about 60 km (18 mi.) along a north-south line from north-central Billings County into southern McKenzie County. Both of these structures are fault-bounded on their …