Digital Commons Network^™

Captive Environmental Influences On Behavior In Zoo Drills And Mandrills (Mandrillus), A Threatened Genus Of Primate, Erik Terdal

Dissertations and Theses

Drills (Mandrillus leucophaeus) are an endangered species of African monkey (Cercopithecidae), and their sole congener the mandrill (Mandrillus sphinx) is vulnerable to extinction. Both species are threatened in the wild by deforestation and hunting.

Drills have a poor record of captive reproduction. Many individuals appear to have behavioral deficiencies which interfere with reproduction. Thus, the zoo population of drills does not serve as a “hedge” against the species’ total extinction: drills are endangered in captivity as well as in the wild. Mandrills, by contrast, reproduce well in captivity. Information on the behavior of mandrills in captivity may help zoo managers …

Wapato For The People : An Ecological Approach To Understanding The Native American Use Of Sagittaria Latifolia On The Lower Columbia River, Melissa Cole Darby

Dissertations and Theses

Sagittaria latifolia Willd. was an important root food and trade commodity for the Indians who lived along the Lower Columbia River in early historic times. This plant was prolific in the extensive wetlands of the Lower Columbia from about the great Cascades to the Kalama River. The tubers of this plant were called "wapato" in Chinook Jargon, the local trade language. The wetlands, and this plant that grew there, occupied a vast extent of the Lower Columbia territory; so much so that this valley was named 'Wapato Valley' by Lewis and Clark in 1805. This thesis will provide pertinent information …

Student Perceptions Of Riots And Boycotts In Secondary Schools In Kenya's Kirinyaga District, Margaret Wangeci Gatimu

Dissertations and Theses

In recent years, a number of secondary schools in the Kirinyaga district of Central Province of Kenya have experienced riots and boycotts. The major objective of this study was to understand why students disrupt the normal processes of schooling. Students' perceptions were obtained by examining their attitudes, ideas, opinions, morals, and myths about these uprisings. The study was phenomenological in nature and was informed by the symbolic interactionism (Bogdan & Biklen, 1992). Data were collected from six diverse secondary schools: three all boys schools, two all girls schools, and one co-educational school. Multiple sources of data and methods of collection …

Jitter And Wander Reduction For A Sonet Ds3 Desynchronizer Using Predictive Fuzzy Control, Kevin Blythe Stanton

Dissertations and Theses

Excessive high-frequency jitter or low-frequency wander can create problems within synchronous transmission systems and must be kept within limits to ensure reliable network operation. The emerging Synchronous Optical NETwork (SONET) introduces additional challenges for jitter and wander attenuation equipment (called desynchronizers) when used to carry payloads from the existing Plesiochronous Digital Hierarchy (PDH), such as the DS3. The difficulty is primarily due to the large phase transients resulting from the pointer-based justification technique employed by SONET (called Pointer Justification Events or PJEs). While some previous desynchronization techniques consider the buffer level in their control actions, none has explicitly considered wander …

Violent Youth Gangs In Portland: A Study Of The City's Response, Debra Lynn Lindberg

Dissertations and Theses

Youth gangs infiltrated Portland's illegal drug trade in the early 1980s. By the mid-1980s, entire neighborhoods in some parts of the city were affected. Residents expressed fear that their children would be drawn into gangs. Violence between rival gangs was frightening. Citizens, law enforcement and social services personnel organized to defend themselves and adjust programs to manage the problem. City officials denied a problem existed until a gang style shooting death forced recognition. The shooting death was catalytic in that it launched an effort to respond with a continuum of services. The House of Umoja was one of the services. …

The Development And Evaluation Of Aggregation Methods For Group Pairwise Comparison Judgments, Sida Zhou

Dissertations and Theses

The basic problem of decision making is to choose the best alternative from a set of competing alternatives that are evaluated under conflicting criteria. In general, the process is to evaluate decision elements by quantifying the subjective judgments. The Analytic Hierarchy Process (AHP) provides us with a comprehensive framework for solving such problems. As pointed out by Saaty, AHP "enables us to cope with the intuitive, the rational, and the irrational, all at the same time, when we make multicriteria and multiactor decisions". Furthermore, in most organizations decisions are made collectively, regardless of whether the organization is public or private. …

A Methodology For Regional Seismic Damage Assessment And Retrofit Planning For Existing Buildings, Thomas C. Mccormack

Dissertations and Theses

Recent geologic research has shown that earthquakes more destructive than formerly expected are likely to occur in the Pacific Northwest. To mitigate catastrophic loss, planners are gathering information to make decision on implementing regional seismic retrofit programs. This research develops a model to estimate regional earthquake losses for existing buildings, and determine optimal retrofit priorities and budgets. Fragility curves are developed to provide earthquake damage estimates for a range of seismic intensities. The published earthquake damage estimates of a large group of prominent earthquake engineering experts are extended to include the combined effect of structure type, earthquake-sensitive variations in building …

An Empirical Study On The Jump-Diffusion Two-Beta Asset Pricing Model, Hongqing Chen

Dissertations and Theses

This dissertation focuses on testing and exploring the usage of the jump-diffusion two-beta asset pricing model. Daily and monthly security returns from both NYSE and AMEX are employed to form various samples for the empirical study. The maximum likelihood estimation is employed to estimate parameters of the jump-diffusion processes. A thorough study on the existence of jump-diffusion processes is carried out with the likelihood ratio test. The probability of existence of the jump process is introduced as an indicator of "switching" between the diffusion process and the jump process. This new empirical method marks a contribution to future studies on …

Solutions Of Linear Equations And A Class Of Nonlinear Equations Using Recurrent Neural Networks, Karl Mathia

Dissertations and Theses

Artificial neural networks are computational paradigms which are inspired by biological neural networks (the human brain). Recurrent neural networks (RNNs) are characterized by neuron connections which include feedback paths. This dissertation uses the dynamics of RNN architectures for solving linear and certain nonlinear equations. Neural network with linear dynamics (variants of the well-known Hopfield network) are used to solve systems of linear equations, where the network structure is adapted to match properties of the linear system in question. Nonlinear equations inturn are solved using the dynamics of nonlinear RNNs, which are based on feedforward multilayer perceptrons. Neural networks are well-suited …

A Semiquantitative Analysis Of Pcb And P,P-Dde Residues In Stranded Marine Mammals Using High Performance Liquid Chromatography, David Lawrence Hayteas

Dissertations and Theses

Organochlorines are ubiquitous pollutants of the marine environment. These lipid-soluble and highly persistent compounds are found in detectable amounts in almost all marine organisms, and accumulate in the lipid tissues of marine animals. This bioaccumulation leads to biomagnification of these contaminants in higher trophic levels. Near the top of many marine food chains are found the marine mammals, in whose blubber high levels of organochlorine residues have been measured. The most commonly occurring of these pollutants in these animals are the polychlorinated biphenyls (PCB's) and p,p-DDE, a metabolite of the insecticide DDT. These substances have been shown to cause disruptions …

Urgent Care Center Location: An Empirical Analysis Of Their Locations In Relation To Demographic, Socioeconomic, And Land Use Factors: A Case Study Of Portland, Oregon, Abdullah Alfaiz

Dissertations and Theses

Urgent Care Centers (UCCs) are a recent innovation in the American system of health care delivery. The number of UCCs has increased significantly in recent years. Many researchers point out that the rapid growth of UCCs is expected to escalate during the next few decades. This growth will create more competition among providers of these facilities in the health care market, and the competition could lead to an uneven distribution of UCCs within cities. While health officials and planners are interested in attracting more patients by expanding UCC services, they are often unfamiliar with the factors that go into site …

Scenery As Policy: Public Involvement In Developing A Management Plan For The Scenic Resources Of The Columbia River Gorge, Gordon Mathews Euler

Dissertations and Theses

The Columbia River Gorge National Scenic Area (NSA) was created in 1986 in response to a growing interest in preserving the scenic beauty of the gorge. The creation of the NSA and other areas around the country with a scenic resource emphasis indicates a growing interest in protecting landscapes with diverse scenic qualities that are not showcase areas such as the Grand Canyon and Yosemite. NSA mandates included the protection and enhancement of scenic, natural, cultural, and recreational resources (SNCRs) as the primary concern in the consideration of new land uses. The NSA management plan contains a complex mix of …

Impact Of The Medical Library Assistance Act Of 1965 On Health Sciences Libraries In The Pacific Northwest: An Interorganizational Approach, Leonoor Swets Ingraham

Dissertations and Theses

Since the 1960's, the number of publications has increased at a phenomenal rate, and the introduction of the computer has resulted in greatly expanded technological advances in information processing and information access. The information delivery component of health sciences libraries has been transformed; and concomitantly, their interorganizational relations have been altered. This research investigates the impact of a federally mandated information program. The Medical Library Assistance Act was passed in 1965 to support the escalating information needs of health professionals. Also, a computerized access system for biomedical literature was introduced by the National Library of Medicine. This study focuses on …

A Policy-Independent Secure X Server, Kirk Joseph Bittler

Dissertations and Theses

This thesis demonstrates that a secure X system can be designed and implemented to be independent of a particular security policy. The advantages and costs of a separation of security policy and enforcement are examined by developing a large scale application, the DX windowing system, on a DTOS platform. DTOS is a high assurance operating system that isolates policy decisions in a Security Server. A security conscious process, such as DX, eliminates policy considerations from the code. The process instead consults the Security Server and enforces the decisions that server derives from the policy. The DX architecture is described and …

Value Measurement For New Product Category: A Conjoint Approach To Eliciting Value Structure, Roland Helmut Heger

Dissertations and Theses

Ability to measure value from the customer's point of view is central to the determination of market offerings: Customers will only buy the equivalent of perceived value, and companies can only offer benefits that cost less to provide than customers are willing to pay. Conjoint analysis is the most popular individual-level value measurement method to determine relative impact of product or service attributes on preferences and other dependent variables. This research focuses on how value measurement can be made more accurate and more reliable by measuring the relative influence of selected methodological variations on performance in prediction and on stability …

Characteristics Of Administrators' Leadership Style In Quality Child Care Centers, Katherine Ann Bobula

Dissertations and Theses

The utilization of center-based child care services by working and student parents has increased dramatically over the last two decades, and has been accompanied by an equally strong interest, among the public and researchers alike, in the establishment and maintenance of quality caregiving in center-based care. This study addresses the leadership characteristics of administrators of quality child care centers. The intent of the study is to add to the existing knowledge concerning the role that the child care center administrator has in maintaining the delivery of high quality child care by the teaching-caregiving staff. Two factors were investigated: the leadership …

Salesforce Involvement In New Product Predevelopment Activities Of High Technology Firms, Candace Petersen

Dissertations and Theses

The strongest correlate of new product success is understanding of market requirements early in the new product development (NPD) process. This is true in high technology environments where rapid change and chaotic market conditions prevail. Although a firm's salesforce is viewed as one of many sources of new product ideas and market information, the involvement of salespeople in NPD activities varies widely across firms. This study examines salesforce involvement in a firm's NPD predevelopment activities, i.e. idea generation and screening, preliminary market assessment, and concept evaluation. Because of the limits of existing research in this area, a two-phase research design …

Factors Occurring In Youth Suicide Behavior In Oregon, Kathy Goss

Dissertations and Theses

There has been an epidemic rate of increase in youth suicide since 1960. Professionals, teachers, counselors and parents want to identify youth at risk of suicide and intervene prior to an attempt or a suicide. The premise of this study is that youth who display similar risk factors as past attempters and completers may be at risk of attempting themselves and can be identified by these risk factors. This is a quantitative and descriptive study of youth suicide attempters and completers in the state of Oregon in 1989 and 1990 in an effort to further identify risk factors of youth …

Determining The Factors Influential In The Validation Of Computer-Based Problem Solving Systems, Leslie Anne Morehead

Dissertations and Theses

Examination of the literature on methodologies for verifying and validating complex computer-based Problem Solving Systems led to a general hypothesis that there exist measurable features of systems that are correlated with the best testing methods for those systems. Three features (Technical Complexity, Human Involvement, and Observability) were selected as the basis of the current study. A survey of systems currently operating in over a dozen countries explored relationships between these system features, test methods, and the degree to which systems were considered valid. Analysis of the data revealed that certain system features and certain test methods are indeed related to …

Mechanisms Of Pentachlorophenol Induced Charge Transport In Lipid Membranes, William Charles Brown

Dissertations and Theses

Pentachlorophenol (PCP) is one of the prominent environmental pollutant that has penetrated into food chain and is present in humans. Health concerns have been raised since daily intake of PCP by the US population is estimated to be 16-19 µg. PCP facilitates dissipation of electrochemical potential gradients of hydrogen ions across energy transducing membranes, which are the energy sources for the conversion of adenosine diphosphate into adenosine triphosphate. Closely linked to these dissipative effects is the development of electrical conductivity in lipid membranes, induced by the presence of PCP. Three modes of PCP - induced membrane electrical conductivity were theoretically …

Complexity Properties Of The Cellular Automaton Game Of Life, Andreas Rechtsteiner

Dissertations and Theses

The Game of Life is probably the most famous cellular automaton. Life shows all the characteristics of Wolfram's complex Class IV cellular automata: long-lived transients, static and propagating local structures, and the ability to support universal computation.

We examine in this thesis questions about the geometry and criticality of Life. We find that Life has two different regimes with different dimensionalities. In the small scale regime Life shows a fractal dimensionality with D_s = 0.658 and in the large scale regime D₁ = 2.0, suggesting that the objects of Life are randomly distributed. We find that Life …

Influence Of Heater Orientation On Fluctuations In Steady-State Nucleate Boiling, William F. Osborne

Dissertations and Theses

In observations of steady-state nucleate boiling, fluctuations in the temperature and heat flux might initially appear to be completely random. However, it was shown that, for a vertically mounted platinum wire in liquid nitrogen, the fluctuations about the steady-state exhibit an average counterclockwise circulation when the heat flux is plotted versus the superheat temperature. An area associated with the average circulation was proposed as a numerical measure of stability for steady-state nucleate boiling. The mechanisms for the generation of these fluctuations are thought to be the feedback of the bubbles rising past the wire and the differential heating and cooling …

Performance Of The Housing Market In Abudhabi City And The Government Housing Policies, Nasser Saif Almansoori

Dissertations and Theses

This research examines the government housing policies and the performance of the housing market in AbuDhabi City. AbuDhabi City and other cities in United Arab Emirates were among the poorest cities in the world about thirty years ago but the new wealth from oil production which started during the early 1960s changed that fact completely. AbuDhabi City, the capital of U.A.E., experienced the most dramatic change in the country as it went through a massive urban transformation. Housing the city's rapidly growing population became among the top priorities of the government and this led to the adoption of many housing …

Evaluable Functions In The GöDel Programming Language: Parsing And Representing Rewrite Rules, Janet Vorvick

Dissertations and Theses

The integration of a functional component into a logic language extends the expressive power of the language. One logic language which would benefit from such an extension is Gödel, a prototypical language at the leading edge of the research in logic programming. We present a modification of the Gödel parser which enables the parsing of evaluable functions in Gödel. As the first part of an extended Gödel, the parser produces output similar to the output from the original Gödel parser, ensuring that Gödel modules are properly handled by the extended-Gödel parser. Parser output is structured to simplify, as much as …

Geochemistry Of The Boring Lava Along The West Side Of The Tualatin Mountains And Of Sediments From Drill Holes In The Portland And Tualatin Basins, Portland, Oregon, Michelle Lynn Barnes

Dissertations and Theses

Instrumental Neutron Activation Analysis (INAA) was used to identify geochemical groups in Boring Lava along the west side of the Tualatin Mountains, and in sediments of the Portland and Tualatin basins. Samples of Boring Lava were obtained from TriMet drill core collected during planning of the tunnel alignment for the Westside Light Rail line. Additional samples of Boring Lava were collected from outcrops along the west side of the Tualatin Mountains. Samples of sediment from the Tualatin and Portland basins were obtained from drill core collected during an Oregon Department of Geology and Mineral Industries (DOGAMI) Earthquake Hazards Mapping project. …

Electrostatic Interactions At Membrane-Water Interfaces And Distribution Of 2, 4, 6-Trichlorophenol In A Membrane Model System, Isolde Sieder

Dissertations and Theses

It is generally accepted that biological membranes consist of a lipid bilayer matrix with proteins incorporated into the lipid bilayer. Typically, these membranes are negatively charged due to the presence of negatively charged lipids in the bilayer as well as negatively charged molecular groups on proteins. Biologically active molecules, such as environmental pollutants, enter the membrane from the aqueous phase by adsorption or partitioning into the lipid bilayer. The thesis consists of two parts. Part I is a computational study of spatial distribution of electric potential in the aqueous portion of the membrane-water interface using two models of charge distribution: …

Treatment Approaches For Pathological Gambling: Review Of Literature And Development Of New Program, Karen Lee Hafner

Dissertations and Theses

Pathological gambling is a treatable, but complex addiction. Defined as out of control gambling that disrupts relationships, employment and/or education. People from all social, economic and cultural groups are affected. Pathological gambling is a problem throughout this country, and in Oregon 61,000 people are estimated to have this disorder. There is a lack of information and extensive misinformation about gambling; and gambling has, historically, been considered a moral weakness. Treatment for pathological gambling is a recent development, and still is not widely available. Pathological gambling is pervasive, poorly understood, and costly and deserves further study. Existing literature on pathological gambling, …

Origins Of Effective Charge Of Multivalent Ions At A Membrane/Water Interface And Distribution Of 2,3,4,5-Tetrachlorophenol In A Membrane Model System, Piet O. Schmidt

Dissertations and Theses

Biological cells and subcellular organelles are surrounded by membranes to form compartments performing specialized functions. Adsorption or partitioning of biologically active compounds into the membrane is the first step in the process of modification of cell function. This work is concerned with the problem of distribution of charged molecules between water and electrically charged membrane surface and between water and octanol. Part I of this thesis is focused on the electrostatic interactions taking place between charges on the membrane and ions present in the aqueous region of the membrane/water interface. The objective was to explore theoretically the origin of anomalous …

The Interaction Between A Thiol Specific Probe (Opa) And The Single Channel Characteristics Of The Reconstituted Ca++ Release Protein From Skeletal Muscle Sarcoplasmic Reticulum, Alexander Braun

Dissertations and Theses

One advantage of higher life-forms over less developed organisms is their ability to respond to signals from their environment with motion. This requires highly specialized contractile cells and a whole locomotion apparatus. In vertebrates, the cells responsible for movement are the skeletal muscle cells. They receive signals from the autonomic nervous system in the form of an action potential, and they contract in an appropriate manner. Calcium is a vital intracellular passenger whose role in muscular function is to initiate contraction. It is released via specific channel proteins from an internal Ca⁺⁺ store, the sarcoplasmic reticulum, and triggers muscular …

Synthesis And Characterization Of Novel Fluorine Containing Alkylsulfonyls And Sulfonates : Fluorinated Sulfonyl Methanes And Derivatives, Nelson R. Holcomb

Dissertations and Theses

A series of salts of the strong fluorocarbon acid bis(trifluoromethylsulfonyl)methane were made: (CF3S02 ) 2CHK, (CF3S02 ) 2CHLi, [ (CF3S02 ) 2CH] 2Ca, [ (CF3S02 ) 2CH] 2Hg, (CF3S02 ) 2CHAg, [ (CF3S02 ) 2CH] 3La. Their reactivity and use as organic intermediates were investigated. The salts were made from their corresponding carbonates, oxides, or hydrides. The reaction times for the salts is generally short, however the purification process was laborious, involving recrystallization from organic solvents and drying under vacuum. The lithium salt is being evaluated as a solid state battery electrolyte. Derivatives of bis(trifluoromethylsulfonyl)methane were made by using the …