Digital Commons Network^™

Discards Of Commercial Fish Species In The Gulf Of Maine Groundfish And Shrimp Fisheries, Richard Langan

Doctoral Dissertations

A three part analysis of discarding of commercial fish species in the Gulf of Maine trawl fisheries was conducted from 1983 through 1992. Abstracts for each part of the dissertation are:

Part 1. The objectives of the research were to quantify commercial trawler discards of American plaice, witch flounder, yellowtail flounder, and winter flounder, and to examine variables that potentially influence discard rates. Data were obtained from 135 tows in 6 areas of the Gulf of Maine. Four different types of trawls were used. Mean discard percentages per tow, on a weight basis, were 25, 18, 13, and 5% for …

Horizontal Distribution, Feeding Rates And Prey Selectivity Of The Littoral Predator, Polyphemus Pediculus, Anne Turner Packard

Doctoral Dissertations

Littoral planktonic communities have rarely been included in food web dynamics and predator/prey behavior studies of planktonic communities of fresh water ecosystems. Polyphemus pediculus, a typically littoral predaceous cladoceran, is common in lakes and ponds throughout the northern temperate zone.

The patchy distribution of Polyphemus in littoral surface waters necessitates the use of a stratified random sampling regime to estimate and monitor Polyphemus populations. The population in Mirror Lake, NH, increased exponentially after the first appearance of parthenogenetic juveniles in late April. An abrupt decline in the population coincided with the movement of small Micropterus dolomieui fry into littoral areas …

A Transmission Electron Microscopy Study Of Defect Generation And Microstructure Development In Ultrasonic Wire Bonding, Nikhil Mohan Murdeshwar

Doctoral Dissertations

Ultrasonic wire bonding is widely used in the electronic industry to connect semiconductor chips to packages. Even though the popularity of the technique has increased in recent times, questions remain about the bonding mechanism, and factors affecting bondability and reliability. In this thesis, answers were provided to many of these questions using TEM to examine bonded cross section and plan view specimens.

A detailed investigation of the Al wire and substrate showed dynamically annealed well recovered grains while microstructural observations of other substrates revealed wide varieties of response mechanisms. For example, Ni formed a dislocation cell structure, Cu formed a …

Performance Of Concrete Beams And Slabs Reinforced With Frp Grids, Edwin Robert Schmeckpeper

Doctoral Dissertations

The objective of this dissertation was to evaluate the suitability of Fiber Reinforced Plastic (FRP) grids for use as a structural reinforcement in concrete structures such as highway bridge decks. The work concentrated on determining the mechanical properties of FRP materials, testing the flexural behavior and servicability of concrete beams and slabs reinforced with FRP grids, and determining splice and development length requirements for FRP grids. Design recommendations concerning failure mode, deflections, anchorage requirements were developed.

The results from the flexural tests on FRP reinforced concrete beams, with reinforcing ratios ranging from 0.3% to 2.2%, showed that the failure mode, …

Characterizing And Improving The Fault Tolerance Of Artificial Neural Networks, Bruce Edmond Segee

Doctoral Dissertations

Artificial neural networks are networks of very simple processing elements based on an approximate model of a biological neuron. It is widely believed that because biological neural networks are tolerant of the loss of individual neurons and because there is a strong analogy between biological neural networks and artificial neural networks, then artificial neural networks must also be inherently fault tolerant. This is, unfortunately, simply not true.

Results reported in this dissertation show that in the task of function approximation the multilayer perceptron is very intolerant of faults to the extent that the loss of a single network parameter can …

The World Of Kavanagh And Cottril: A Portrait Of Irish Emigration, Entrepreneurship, And Ethnic Diversity In Mid-Maine, 1760-1820, Edward Thomas Mccarron

Doctoral Dissertations

This dissertation examines a remarkable and little known episode in the peopling of early New England: The founding of an Irish-Catholic community in Lincoln County, Maine, 1760-1820. It details the experience of over three hundred Irish families, tracing them to their Old World origins, following their progress across the Atlantic, and documenting their efforts to establish an ethnic and religious identity on the Maine frontier.

Their story parallels the lives of two immigrants, James Kavanagh and Matthew Cottril, who made a fortune in the Maine timber trade and encouraged kin and countrymen to settle in the new land. Their career …

The Role Of Lipoteichoic Acid And The Leukocyte Integrins In The Binding Of Group B Streptococci To Murine Peritoneal Macrophages, Anne Ragonese Sloan

Doctoral Dissertations

The macrophage has been shown to bind potentially pathogenic bacteria in the absence of serum components, but the mechanism is not well understood. The macrophage is a key component of our non-inducible defenses and this form of innate immunity is of particular importance for individuals in which the immune system may be sub-optimally functional, e.g., neonatal and geriatric individuals, and for sites in the body in which serum enhancement through opsonins is thought to be insufficient, e.g., lungs. To understand the mechanism by which mammalian innate host defenses respond to potential microbial aggression by opportunistic microorganisms, I developed two assays …

Solar Flares: The Onset Of Magnetic Reconnection And The Structure Of Radiative Slow-Mode Shocks, Peng Xu

Doctoral Dissertations

This is a theoretical study of two magnetohydrodynamic (MHD) processes associated with magnetic reconnection in large solar flares and other related eruptive phenomena.

The first process determines the effect of magnetic reconnection in the corona upon the loss of equilibrium triggered by the slow evolution of the field lines mapping to the region in the photosphere where the flare occurs. The quasi-static MHD equations are solved for a magnetic field configuration which satisfies line-tied boundary conditions during the eruption of the flare. Such boundary conditions occur because the inertial mass of the photosphere plasma is much greater than that of …

On Her Mouth You Kiss Your Own: Lesbian Conversations In Exile, 1924-1936, Luita Deane Spangler

Doctoral Dissertations

This dissertation examines the work of four American lesbian expatriate novelists living and writing in Paris in the years between the two World Wars. Altogether six novels are discussed: The Uncertain Feast (1924), The Happy Failure (1925), and This Way Up (1927) by Solita Solano; The Cubical City (1925) by Janet Flanner; The One Who Is Legion (1930) by Natalie Clifford Barney; and Nightwood (1936) by Djuna Barnes.

Guided by recent conjectures on the significance of sexuality and gender development proposed by such feminist theorists as Luce Irigaray and Monique Wittig, this dissertation explores these six novels for evidence of …

Factors Controlling Fluxes Of Volatile Sulfur Compounds In Sphagnum Peatlands, William Zamboni De Mello

Doctoral Dissertations

Exchange of DMS and OCS between the surface of Sphagnum peatlands and the atmosphere were measured with dynamic (S-free sweep air) and static enclosures. DMS emission rates determined by both methods were comparable. The dynamic method provided positive OCS flux rates (emission) for measurements performed at sites containing Sphagnum. Conversely, data from the static method indicated that OCS was consumed from the atmosphere.

Short and long-term impacts of increased S deposition on fluxes of volatile S compounds (VSCs) from Sphagnum peatlands were investigated in a poor fen (Mire 239) at the Experimental Lakes Area, Ontario, Canada. Additional experiments were conducted …

Beliefs, Autonomy, And Mathematical Knowledge, Judy Ann Rector

Doctoral Dissertations

The purpose of this study was to investigate the apparent effects of students' beliefs about mathematics and autonomy on their learning of mathematics. The study utilized a multiple-case study design with analysis by and across cases. The cases represented six high school students enrolled in either Algebra II or Algebra II/Trigonometry. Data was collected in three phases: (a) classroom observations and assessment of the teacher's perception of her role in the learning process, (b) an assessment of students' beliefs about mathematics and autonomy, and (c) an assessment of students' newly formed mathematical constructs on functions.

The beliefs' assessment included observing …

Resonance Absorption Of Mhd Surface Waves With Applications To The Solar Atmosphere, Guang Yang

Doctoral Dissertations

This thesis studies the physics of resonance absorption of MHD surface waves and examines the effects of velocity shear on the rate of resonance absorption. Theoretical analyses and numerical calculations demonstrate that resonance absorption of MHD surface waves is a viable mechanism for heating of the solar corona.

It is shown that resonance absorption has a very simple physical interpretation in terms of driven harmonic oscillators. This insight greatly simplifies the mathematics and allows a thorough discussion of the solar coronal heating. It is found that resonance absorption of MHD surface waves can occur rapidly enough to heat the solar …

Traces: Modeling The Teaching Consultant In A Problem-Solving Domain, Brian Leigh Johnson

Doctoral Dissertations

A model of a teaching consultant is presented. The teaching consultant, an extension of the concept of a computer coach, is concerned with filling gaps in a student's knowledge base relative to a specific application. The student model used by the consultant is stored in the form of a prerequisite network, which maintains nodes of information that are connected so that prerequisite information may be readily accessed. The Teaching Consultant Model is being used as the basis for an intelligent tutoring system serving as a programming consultant for novice programmers.

Predator-Prey Interactions Between Fish And Insects In Streams, Graham Edward Forrester

Doctoral Dissertations

Some benthic insects in streams disperse by drifting short distances downstream in the water column. While drifting they are at risk from predators, such as trout, that feed in the water column. I examined prey selection by brook trout (Salvelinus fontinalis L.) in Stoney Brook, New Hampshire, U.S.A., and effects of trout on drift dispersal and benthic density of five prey taxa (mayflies: Ephemeroptera).

Effects of trout on mayflies were tested by field manipulation of trout density in replicate 35 m long sections of stream. Trout consumed all five mayflies in roughly similar numbers. Feeding rates of trout (by weight) …

Isotope Geochemistry And Paleobiology Of The Devils Lake Basin, North Dakota, Robert Mulvihill Lent

Doctoral Dissertations

Devils Lake is located in one of the largest closed basins in the northern prairies. Water and sediment samples were collected to characterize present and past hydrologic and climatic conditions in the basin.

Precipitation in North Dakota exhibits a wide range of stable isotopic compositions. Precipitation samples clustered along two segments of the meteoric water line, illustrating the strong seasonal component of precipitation. Low deuterium excess in summer precipitation was indicative of higher relative humidity of the air masses originating over the Gulf of Mexico. High deuterium excess in winter precipitation is similar to the values found at Canadian stations …

Mechanistic And Exploratory Organic Photochemistry And The Synthesis Of Strained Cyclic Cumulenes, Mary Morgan Kirchhoff

Doctoral Dissertations

The photoaddition of 1,2-cyclononadiene to naphthalene gives para adducts as the primary products, accompanied by a minor amount of the meta cycloadduct. Photolysis of naphthalene and 1,2-nonadiene did not yield any addition products, nor did irradiation of anthracene and 1,2-cyclononadiene, indicating that the reaction is sensitive to the structure of both the allene and arene.

Dichlorocarbene can be cleanly generated photochemically by irradiation of 7,7-dichlorodibenzo (a;c) bicyclo (4.1.0) heptane. This new method of producing dichlorocarbene permitted the first measurement of the absolute rate constants for the addition of dichlorocarbene to a series of olefins. Additional studies on this carbene included …

Geochronology And Geochemistry Of The Basement Orthogneisses Of The Araguaia Belt, Brazil, Candido A Veloso Moura

Doctoral Dissertations

Orthogneisses representing the basement rocks of the Araguaia belt (AB), Brazil, are exposed in the core of dome-like structures. Gneisses of trondhjemitic, tonalitic, and granodioritic (TTG) composition constitute the Colmeia Complex, while augen gneiss, of granitic composition, is termed Cantao Gneiss (CG). An Archean age is suggested for the TTG gneisses, although the available Rb-Sr ages for these rocks range between 1.8 and 2.6 Ga. A Rb-Sr age of 1.77 Ga for the CG is interpreted either as a crystallization age or a resetting age.

Geochronological and geochemical studies of the orthogneisses of five of these dome-like structures of the …

Corrosion Protection Of Metals By Poly(3-Methylthiophene) Coatings, Shouxian Ren

Doctoral Dissertations

Electrochemically prepared poly(3-methylthiophene) (P3MT) films were used as conductive polymer coatings to poise a substrate metal in the passive potential range in corrosive media. To firmly adhere P3MT coatings onto substrate metals, different methods were developed for each metal; stainless steel (430SS), titanium (TiGr2) and carbon steel (C1010). The samples were either pretreated by anodization in phosphate solution to form a uniform porous surface or pitted by chloride ions simultaneously with the formation of an adhesive thin film. Coatings were characterized for various galvanostatic electropolymerization conditions on both platinum and phosphated 430SS (Ph430SS) rotating disk electrodes (RDEs). Both applied current …

Arene-Alkene Meta Photocycloadditions And Conjugated Enyne Photorearrangements, Manli Zheng

Doctoral Dissertations

The new advances and synthetic potential of arene-alkene meta photocycloadditions, with the goal of rapid approach to polycyclic molecules, are described. Vinyl cyclohexanecarboxylate has been found to be an efficient alkene moiety to improve the reaction efficiency by reducing formation of polymers during irradiation. Exploration of asymmetric meta photocycloaddition, via chiral auxiliaries, resulted in partial asymmetric induction. Fluorescence studies have led to a better understanding of the reaction mechanism. Intramolecular isotope effect results on meta photocycloaddition remain unexplained.

Conjugated enynes undergo a singlet photorearrangement, resulting in a pseudodegenerate rearrangement. The synthesis of starting materials, characterization of products, studies of the …

Genetic And Morphological Variation And Differentiation Of South Korean Natural Populations Of Wild Soybean, Glycine Soja Sieb And Zucc, Hongrun Yu

Doctoral Dissertations

Genetic variation is the basis of crop improvement. As genetic background narrows in the cultivated germplasm, genes need to be introduced from new sources. Glycine soja is a wild relative of the cultivated soybean, glycine max (L.) Merr. It can be used in soybean breeding. Evaluation of wild soybean populations is not only necessary for use in cultivar improvement, will also provide information about origin, migration, evolution and natural selection of this species. Seeds were collected from six natural populations in South Korea to study the genetic variation and differentiation of wild soybean.

The study was divided into two parts: …

A Neural Network-Based Trajectory Planner For Redundant Systems Using Direct Inverse Modeling, Franklin J. Rudolph

Doctoral Dissertations

Redundant (i.e., under-determined) systems can not be trained effectively using direct inverse modeling with supervised learning, for reasons well out-lined by Michael Jordan at MIT. There is a "loop-hole", however, in Jordan's preconditions, which seems to allow just such an architecture. A robot path planner implementing a cerebellar inspired "habituation" paradigm with such an architecture will be introduced. The system, called ARTFORMS, for "Adaptive Redundant Trajectory Formation System" uses on-line training of multiple CMACS. CMACs are locally generalizing networks, and have an a priori deterministic geometric input space mapping. These properties together with on-line learning and rapid convergence satisfy the …

To Rend And Teare The Bodies Of Men: Theology And The Body In Demonic Possession; France, England, And Puritan America, 1550-1700, Julianne Siudowski Cooper-Forst

Doctoral Dissertations

During the Reformation, Protestants attempted to recast their theology in opposition to the Roman Catholic system. They succeeded in most areas. There was, however, one area of theology where this was not true: demonology and spiritual possession. Incidents of demonic possession rose during the second quarter of the sixteenth century, reached a crescendo by the first quarter of the seventeenth century, and except for a flurry or two, died out near the beginning of the eighteenth century. This dissertation examines the published materials relating to the physical phenomena of demonic possession in France, England, and Puritan America from the sixteenth …

The World Of Kavanagh And Cottril: A Portrait Of Irish Emigration, Entrepreneurship, And Ethnic Diversity In Mid-Maine, 1760-1820, Edward Thomas Mccarron

Doctoral Dissertations

This dissertation examines a remarkable and little known episode in the peopling of early New England: The founding of an Irish-Catholic community in Lincoln County, Maine, 1760- 1820. It details the experience of over three hundred Irish families, tracing them to their Old World origins, following their progress across the Atlantic, and documenting their efforts to establish an ethnic and religious identity on the Maine frontier.

Their story parallels the lives of two immigrants, James Kavanagh and Matthew Cottril, who made a fortune in the Maine timber trade and encouraged kin and countrymen to settle in tne new land. Their …