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Electronic Theses and Dissertations

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Creating Geo-Specific Road Databases From Aerial Photos For Driving Simulation, Dahai Guo Jan 2005

Creating Geo-Specific Road Databases From Aerial Photos For Driving Simulation, Dahai Guo

Electronic Theses and Dissertations

Geo-specific road database development is important to a driving simulation system and a very labor intensive process. Road databases for driving simulation need high resolution and accuracy. Even though commercial software is available on the market, a lot of manual work still has to be done when the road crosssectional profile is not uniform. This research deals with geo-specific road databases development, especially for roads with non-uniform cross sections. In this research, the United States Geographical Survey (USGS) road information is used with aerial photos to accurately extract road boundaries, using image segmentation and data compression techniques. Image segmentation plays …

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Nondestructive Evaluation Of Thermal Barrier Coatings With Thermal Wave Imaging And Photostimulated Luminescence Spectroscopy, Barbara Franke Jan 2005

Nondestructive Evaluation Of Thermal Barrier Coatings With Thermal Wave Imaging And Photostimulated Luminescence Spectroscopy, Barbara Franke

Electronic Theses and Dissertations

Gas Turbine manufacturers strive for increased operating temperatures of gas turbine engines to improve efficiency and performance. One method of increasing the temperature beyond material limits is by applying thermal barrier coatings (TBCs) to hot section components. TBCs provide a thermal gradient between the hot gases and metallic substrate, and allow an increase in turbine inlet temperatures of 100-150ºC. However, spallation of TBCs can cause catastrophic failure of turbine engines by incipient melting of the substrate. To prevent such an occurrence, non-destructive evaluation (NDE) techniques are critical for quality control, health monitoring, and life assessment of TBCs. Two techniques in …

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A New Paradigm Of Modeling Watershed Water Quality, Fan Zhang Jan 2005

A New Paradigm Of Modeling Watershed Water Quality, Fan Zhang

Electronic Theses and Dissertations

Accurate models to reliably predict sediment and chemical transport in watershed water systems enhance the ability of environmental scientists, engineers and decision makers to analyze the impact of contamination problems and to evaluate the efficacy of alternative remediation techniques and management strategies prior to incurring expense in the field. This dissertation presents the conceptual and mathematical development of a general numerical model simulating (1) sediment and reactive chemical transport in river/stream networks of watershed systems; (2) sediment and reactive chemical transport in overland shallow water of watershed systems; and (3) reactive chemical transport in three-dimensional subsurface systems. Through the decomposition …

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Design And Implementation Of Wireles Sensor Networks For Parking Management System, Sudhir Chandrasekar Kora Jan 2005

Design And Implementation Of Wireles Sensor Networks For Parking Management System, Sudhir Chandrasekar Kora

Electronic Theses and Dissertations

The technology of wirelessly networked micro sensors promises to revolutionize the way we interact with the physical environment. A new approach to solve parking-related issues of vehicles in parking lots using wireless sensor networks is presented. This approach enables the implementation of the Parking Management System (PMS®) in public parking lots found in Airports, Commercial Buildings, Universities, etc. The design architecture of the sensor nodes is discussed here. An overall view of the sensor network, which covers the whole of the parking lot, is also summarized. Detailed description of the software architecture that supports the hardware is provided. A sample …

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Optimization Of An Unstructured Finite Element Mesh For Tide And Storm Surge Modeling Applications In The Western North Atlantic Ocean, Satoshi Kojima Jan 2005

Optimization Of An Unstructured Finite Element Mesh For Tide And Storm Surge Modeling Applications In The Western North Atlantic Ocean, Satoshi Kojima

Electronic Theses and Dissertations

Recently, a highly resolved, finite element mesh was developed for the purpose of performing hydrodynamic calculations in the Western North Atlantic Tidal (WNAT) model domain. The WNAT model domain consists of the Gulf of Mexico, the Caribbean Sea, and the entire portion of the North Atlantic Ocean found west of the 60° W meridian. This high resolution mesh (333K) employs 332,582 computational nodes and 647,018 triangular elements to provide approximately 1.0 to 25 km node spacing. In the previous work, the 333K mesh was applied in a Localized Truncation Error Analysis (LTEA) to produce nodal density requirements for the WNAT …

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Benchmark Studies For Structural Health Monitoring Using Analytical And Experimental Models, Jason Lee Burkett Jan 2005

Benchmark Studies For Structural Health Monitoring Using Analytical And Experimental Models, Jason Lee Burkett

Electronic Theses and Dissertations

The latest bridge inventory report for the United States indicates that 25% of the highway bridges are structurally deficient or functionally obsolete. With such a large number of bridges in this condition, safety and serviceability concerns become increasingly relevant along with the associated increase in user costs and delays. Biennial inspections have proven subjective and need to be coupled with standardized non-destructive testing methods to accurately assess a bridge's condition for decision making purposes. Structural health monitoring is typically used to track and evaluate performance, symptoms of operational incidents, anomalies due to deterioration and damage during regular operation as well …

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The Use Of The Ucf Driving Simiulator To Test The Contribution Of Larger Size Vehicles (Lsvs) In Rear-End Collisions And Red Light Running On Intersections., Rami Charles Harb Jan 2005

The Use Of The Ucf Driving Simiulator To Test The Contribution Of Larger Size Vehicles (Lsvs) In Rear-End Collisions And Red Light Running On Intersections., Rami Charles Harb

Electronic Theses and Dissertations

Driving safety has been an issue of great concern in the United States throughout the years. According to the National Center for Statistics and Analysis (NCSA), in 2003 alone, there were 6,267,000 crashes in the U.S. from which 1,915,000 were injury crashes, including 38,764 fatal crashes and 43,220 human casualties. The U.S. Department of Transportation spends millions of dollars every year on research that aims to improve roadway safety and decrease the number of traffic collisions. In spring 2002, the Center for Advanced Traffic System Simulation (CATSS), at the University of Central Florida, acquired a sophisticated reconfigurable driving simulator. This …

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Development Of A Knowledge Management Model In Large-Scale International Space Science Projects, Jose Luis Nunez Jan 2005

Development Of A Knowledge Management Model In Large-Scale International Space Science Projects, Jose Luis Nunez

Electronic Theses and Dissertations

Large-scale international science projects (LISPs) are those projects where two or more countries formally agree to cooperate toward the achievement of a scientific, research and development, or engineering goal. In general, only projects exceeding $1 billion U.S. are considered LISPs, so sheer size commands attention, and because they are so costly and visible, failure can lead to significant scientific, financial and political consequences. This researched focused on how 7 different critical success factors impacted the level of technical interface knowledge shared among international partners involved in a large-scale international space science project (LISSP) – the International Space Station (ISS), which …

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Assessment Framework For The Evaluation And Prioritization Of University Technologies For Licensing And Commercialization, Ahmad D. Rahal Jan 2005

Assessment Framework For The Evaluation And Prioritization Of University Technologies For Licensing And Commercialization, Ahmad D. Rahal

Electronic Theses and Dissertations

US corporations have long recognized university related scientific research as an important source of long term economic growth and technological innovation. This dynamic involvement with industry has drastically increased the university technology transfer and licensing activities, and has stretched the human and financial resources of Technology Management and Licensing Offices of many US universities. This research provides a mechanism that can aid in the complex process of properly assessing university-owned technologies and intellectual properties, to identify those with licensing and commercialization potential for the pursuit of truly important breakthrough discoveries. This research focuses on the university technology licensing and commercialization …

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Designing A Document Delivery System For Ucf S Interlibrary Loan Department, Abha Y. Trivedi Jan 2005

Designing A Document Delivery System For Ucf S Interlibrary Loan Department, Abha Y. Trivedi

Electronic Theses and Dissertations

Interlibrary Loan entails obtaining copies of library materials not found in the library's collection on behalf of the library's patrons (borrowing), as well as providing copies of library materials requested by other libraries (lending). The dynamic nature of today's library environment is well illustrated by the rapid changes occurring in the role of interlibrary loan. The vision statement of the University of Central Florida Library is: The library performs a central role of adding value to information for the academic community by creatively improving and providing information resources and services. The library strives to create an environment that encourages the …

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Quality Of Service Measures At Signalized Intersections, Kamal Goyal Jan 2005

Quality Of Service Measures At Signalized Intersections, Kamal Goyal

Electronic Theses and Dissertations

The concept of using qualitative measures to describe the quality of service at signalized intersections provided by different designs and controls has been discussed in numerous conferences. Such measures may include driver's comfort, convenience, anxiety, and preferences. The primary objective of this study was to demonstrate the feasibility of using the University of Central Florida's interactive driving simulator to execute several scenarios involving different unusual design and operation practices to measure the quality of service at a signalized intersection. This thesis describes the scenarios, the experiments conducted, the data collected, and analysis of results. Signalized intersections with 3 types of …

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Design And Synthesis Of Clockless Pipelines Based On Self-Resetting Stage Logic, Abdelhalim Alsharqawi Jan 2005

Design And Synthesis Of Clockless Pipelines Based On Self-Resetting Stage Logic, Abdelhalim Alsharqawi

Electronic Theses and Dissertations

For decades, digital design has been primarily dominated by clocked circuits. With larger scales of integration made possible by improved semiconductor manufacturing techniques, relying on a clock signal to orchestrate logic operations across an entire chip became increasingly difficult. Motivated by this problem, designers are currently considering circuits which can operate without a clock. However, the wide acceptance of these circuits by the digital design community requires two ingredients: (i) a unified design methodology supported by widely available CAD tools, and (ii) a granularity of design techniques suitable for synthesizing large designs. Currently, there is no unified established design methodology …

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Stormwater Irrigation Of Saint Augustine Grass: Nitrogen Balance And Evapotranspiration, Ewoud Hulstein Jan 2005

Stormwater Irrigation Of Saint Augustine Grass: Nitrogen Balance And Evapotranspiration, Ewoud Hulstein

Electronic Theses and Dissertations

A change in surface condition of a watershed, which is usually caused by development, can have measured effects on the naturally occurring hydrologic cycle and nitrogen cycle. This could result in environmental problems, such as reduced springflow and eutrophication. In an effort to address these issues, a combination of best management practices (BMPs) can be adhered to. The practice of using excess stormwater as a source for irrigation is proposed as a BMP for the minimization of impacts by development to the hydrologic and nitrogen cycles. To study the proposed BMP, a field experiment was installed in an outdoor location …

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Frequency Domain Independent Component Analysis Applied To Wireless Communications Over Frequency-Selective Channels, Yuan Liu Jan 2005

Frequency Domain Independent Component Analysis Applied To Wireless Communications Over Frequency-Selective Channels, Yuan Liu

Electronic Theses and Dissertations

In wireless communications, frequency-selective fading is a major source of impairment for wireless communications. In this research, a novel Frequency-Domain Independent Component Analysis (ICA-F) approach is proposed to blindly separate and deconvolve signals traveling through frequency-selective, slow fading channels. Compared with existing time-domain approaches, the ICA-F is computationally efficient and possesses fast convergence properties. Simulation results confirm the effectiveness of the proposed ICA-F. Orthogonal Frequency Division Multiplexing (OFDM) systems are widely used in wireless communications nowadays. However, OFDM systems are very sensitive to Carrier Frequency Offset (CFO). Thus, an accurate CFO compensation technique is required in order to achieve acceptable …

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Estimation Of Hybrid Models For Real-Time Crash Risk Assessment On Freeways, Anurag Pande Jan 2005

Estimation Of Hybrid Models For Real-Time Crash Risk Assessment On Freeways, Anurag Pande

Electronic Theses and Dissertations

Relevance of reactive traffic management strategies such as freeway incident detection has been diminishing with advancements in mobile phone usage and video surveillance technology. On the other hand, capacity to collect, store, and analyze traffic data from underground loop detectors has witnessed enormous growth in the recent past. These two facts together provide us with motivation as well as the means to shift the focus of freeway traffic management toward proactive strategies that would involve anticipating incidents such as crashes. The primary element of proactive traffic management strategy would be model(s) that can separate 'crash prone' conditions from 'normal' traffic …

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Control And Topology Improvements In Half-Bridge Dc-Dc Converters, Songquan Deng Jan 2005

Control And Topology Improvements In Half-Bridge Dc-Dc Converters, Songquan Deng

Electronic Theses and Dissertations

Efficiency and transient response are two key requirements for DC-DC converters. Topology and control are two key topics in this dissertation. A variety of techniques for DC-DC converter performance improvement are presented in this work. Focusing on the efficiency issue, a variety of clamping techniques including both active and passive methods are presented after the ringing issues in DC-DC converters are investigated. By presenting the clamping techniques, a big variety of energy management concepts are introduced. The active bridge-capacitor tank clamping and FET-diode-capacitor tank clamping are close ideas, which transfer the leakage inductor energy to clamping capacitor to prevent oscillation …

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Qos In Cognitive Packet Networks: Adaptive Routing, Flow And Congestion Control, Pu Su Jan 2005

Qos In Cognitive Packet Networks: Adaptive Routing, Flow And Congestion Control, Pu Su

Electronic Theses and Dissertations

With the emergence of various applications that have different Quality of Service (QoS) requirements, the capability of a network to support QoS becomes more and more important and necessary. This dissertation explores QoS in Cognitive Packet Networks (CPN) by using adaptive routing, flow and congestion control. We present a detailed description and analysis of our proposed routing algorithms based on single and multiple QoS constraints. An online estimation of packet loss rate over a path is introduced. We implement and evaluate the adaptive routing scheme in an experimental CPN test-bed. Our experiments support our claims that the users can achieve …

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Access Games: A Game Theoretic Framework For Fair Bandwidth Sharing In Distributed Systems, Sudipta Rakshit Jan 2005

Access Games: A Game Theoretic Framework For Fair Bandwidth Sharing In Distributed Systems, Sudipta Rakshit

Electronic Theses and Dissertations

In this dissertation, the central objective is to achieve fairness in bandwidth sharing amongst selfish users in a distributed system. Because of the inherent contention-based nature of the distributed medium access and the selfishness of the users, the distributed medium access is modeled as a non-cooperative game; designated as the Access Game. A p-CSMA type medium access scenario is proposed for all the users. Therefore, in the Access Game, each user has two actions to choose from: "transmit" and "wait". The outcome of the Access Game and payoffs to each user depends on the actions taken by all the users. …

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Debris Tracking In A Semistable Background, Karthikkalathi Vanumamalai Jan 2005

Debris Tracking In A Semistable Background, Karthikkalathi Vanumamalai

Electronic Theses and Dissertations

Object Tracking plays a very pivotal role in many computer vision applications such as video surveillance, human gesture recognition and object based video compressions such as MPEG-4. Automatic detection of any moving object and tracking its motion is always an important topic of computer vision and robotic fields. This thesis deals with the problem of detecting the presence of debris or any other unexpected objects in footage obtained during spacecraft launches, and this poses a challenge because of the non-stationary background. When the background is stationary, moving objects can be detected by frame differencing. Therefore there is a need for …

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Resource Allocation Schemes And Performance Evaluation Models For Wavelength Division Multiplexed Optical Networks, Mounire El Houmaidi Jan 2005

Resource Allocation Schemes And Performance Evaluation Models For Wavelength Division Multiplexed Optical Networks, Mounire El Houmaidi

Electronic Theses and Dissertations

Wavelength division multiplexed (WDM) optical networks are rapidly becoming the technology of choice in network infrastructure and next-generation Internet architectures. WDM networks have the potential to provide unprecedented bandwidth, reduce processing cost, achieve protocol transparency, and enable efficient failure handling. This dissertation addresses the important issues of improving the performance and enhancing the reliability of WDM networks as well as modeling and evaluating the performance of these networks. Optical wavelength conversion is one of the emerging WDM enabling technologies that can significantly improve bandwidth utilization in optical networks. A new approach for the sparse placement of full wavelength converters based …

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Promoting The Health Needs Of Homeless Women Residing In An Urban Community: A Participatory Action Research Study, Shirley Smith Jan 2005

Promoting The Health Needs Of Homeless Women Residing In An Urban Community: A Participatory Action Research Study, Shirley Smith

Electronic Theses and Dissertations

The purpose of this study was to discover the health promoting needs of homeless women, residing in a shelter. A qualitative participatory action research (PAR) approach was used to solicit a deeper understanding of the women's health promoting needs. PAR is designed as a systematic inquiry, including collaboration with those affected by the issue being studied for purposes of taking action, empowerment, and effecting change. The specific aims for this study were 1) describe the health promoting needs of homeless women in the context of their lives as homeless women; 2) develop and implement a plan for meeting the health …

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Effects Of Content Augmentation Strategies In An Instructional Virtual Environment, Roger Hamilton Jan 2005

Effects Of Content Augmentation Strategies In An Instructional Virtual Environment, Roger Hamilton

Electronic Theses and Dissertations

Content augmentation strategies (CAS) are instructional methods which specify the overlaying of content objects by content augmentation objects in order to increase the effectiveness and efficiency of instruction. The goals of this research were to build a comprehensive framework around CASs, determine the experimental effects of CASs in an instructional virtual environment (VE), and make recommendations regarding the employment and further study of CASs in instructional virtual environments. The VE experiment examined the effectiveness and efficiency impact of six different content augmentation strategies which overlayed different content augmentation objects onto four immersive VE scenarios. Sixty university students, 40 men and …

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Development Of An Artificial Neural Networks Model To Estimate Delay Using Toll Plaza Transaction Data, Aparna Muppidi Jan 2005

Development Of An Artificial Neural Networks Model To Estimate Delay Using Toll Plaza Transaction Data, Aparna Muppidi

Electronic Theses and Dissertations

In spite of the most up-to-date investigation of the relevant techniques to analyze the traffic characteristics and traffic operations at a toll plaza, there has not been any note worthy explorations evaluating delay from toll transaction data and using Artificial Neural Networks (ANN) at a toll plaza. This thesis lays an emphasis on the application of ANN techniques to estimate the total vehicular delay according to the lane type at a toll plaza. This is done to avoid the laborious task of extracting data from the video recordings at a toll plaza. Based on the lane type a general methodology …

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Neural Network Trees And Simulation Databases: New Approaches For Signalized Intersection Crash Classification And Prediction, Piyush Nawathe Jan 2005

Neural Network Trees And Simulation Databases: New Approaches For Signalized Intersection Crash Classification And Prediction, Piyush Nawathe

Electronic Theses and Dissertations

Intersection related crashes form a significant proportion of the crashes occurring on roadways. Many organizations such as the Federal Highway Administration (FHWA) and American Association of State Highway and Transportation Officials (AASHTO) are considering intersection safety improvement as one of their top priority areas. This study contributes to the area of safety of signalized intersections by identifying the traffic and geometric characteristics that affect the different types of crashes. The first phase of this thesis was to classify the crashes occurring at signalized intersections into rear-end, angle, turn and sideswipe crash types based on the traffic and geometric properties of …

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Investigation Of High-K Gate Dielectrics And Metals For Mosfet Devices., Sriram Mannargudi Seshadri Jan 2005

Investigation Of High-K Gate Dielectrics And Metals For Mosfet Devices., Sriram Mannargudi Seshadri

Electronic Theses and Dissertations

Progress in advanced microlithography and deposition techniques have made feasible high- k dielectric materials for MOS transistors. The continued scaling of CMOS devices is pushing the Si-SiO2 to its limit to consider high-k gate dielectrics. The demand for faster, low power, smaller, less expensive devices with good functionality and higher performance increases the demand for high-k dielectric based MOS devices. This thesis gives an in-depth study of threshold voltages of PMOS and NMOS transistors using various high-k dielectric materials like Tantalum pent oxide (Ta2O5), Hafnium oxide (HfO2), Zirconium oxide (ZrO2) and Aluminum oxide (Al2O3) gate oxides. Higher dielectric constant may …

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Voice Track Computer Based Simulation For Medical Training, Alpesh Purshottam Makwana Jan 2005

Voice Track Computer Based Simulation For Medical Training, Alpesh Purshottam Makwana

Electronic Theses and Dissertations

Varying the delivery rate of audio-based text within web-based training increases the effectiveness of the learning process and improves retention when compared with a fixed audio-based text delivery rate. To answer this question, two groups of 20 participants and one group of 10 participants were tested using the Web-based Anatomy & Physiology course modules developed by Medsn, Inc. The control group received the static speed of 128 words per minute while the experimental group received the initial speed of 128 words per minute with the option to change the speed of the audio-based text. An additional experimental group received the …

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Optimizing The Performance Of As-Manufactured Grazing Incidence X-Ray Telescopes Using Mosaic Detector Arrays, Martina Atanassova Jan 2005

Optimizing The Performance Of As-Manufactured Grazing Incidence X-Ray Telescopes Using Mosaic Detector Arrays, Martina Atanassova

Electronic Theses and Dissertations

The field of X-ray astronomy is only forty (43) years old, and grazing incidence X-ray telescopes have only been conceived and designed for a little over fifty (50) years. The Wolter Type I design is particularly well suited for stellar astronomical telescopes (very small field-of-view). The first orbiting X-ray observatory, HEAO-1 was launched in 1977, a mere twenty-eight (28) years ago. Since that time large nested Wolter Type I X-ray telescopes have been designed, build, and launched by the European Space Agency (ROSAT) and NASA (the Chandra Observatory). Several smaller grazing incidence telescopes have been launched for making solar observations …

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Social Work Values And Hospital Culture: An Examination From A Competing Values Framework, Amanda Evans Jan 2005

Social Work Values And Hospital Culture: An Examination From A Competing Values Framework, Amanda Evans

Electronic Theses and Dissertations

The purpose of this study is to assess the perceptions of social workers employed in Florida hospitals in relation to the core values of their profession and the alignment of those values within the culture of their current work setting. The conceptual framework for the study was from organizational behavior theory specific to culture, values, and trust. The Competing Values Framework (Cameron & Quinn, 1999) provided a method to distinguish co-existing competing values within an organization. The research findings indicated that 65% of the professional social workers who participated in the study perceived that the core values of their profession …

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Union Impact On Police Expenditures In Florida, Laurence Putchinski Jan 2005

Union Impact On Police Expenditures In Florida, Laurence Putchinski

Electronic Theses and Dissertations

The continued steady growth of public sector unions compels public administrators to understand the influence labor organizations exert upon local governments. The following study demonstrates the extent of union influence upon police expenditures in Florida. Union influence not only increases total police expenditures and personal services expenditures, it also causes operating expenses to rise. Union influence is less pronounced, and possibly even non-existent in capital outlays expenditures because of possible lack of interest on the part of the union in this area and also because of the existence of economically predetermined policies regarding capital outlays such as vehicle purchases. Public …

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Grassland And Woodland Bird Occurrence And Habitat Selection In The Prairie-Forest Transition Zone Of Minnesota, Thomas Robert Cooper Jan 2005

Grassland And Woodland Bird Occurrence And Habitat Selection In The Prairie-Forest Transition Zone Of Minnesota, Thomas Robert Cooper

Electronic Theses and Dissertations

Numerous species of woodland and grassland nesting birds have experienced population declines in the midwestern United States. Habitat loss and habitat fragmentation are suspected to be two of the underlying causes for the population declines of woodland and grassland birds. The Minnesota Valley Wetland Management District (WMD) covers 14 counties in southeastern Minnesota in the transition zone between forested and prairie ecoregions. Little information is available relative to which birds are using grassland or woodland habitat within the WMD and how their presence or absence is related to the available habitat conditions. Therefore, my study objectives were to: 1) determine …

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