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Characterization Of Chlorinated Ethene Degradation In A Vertical Flow Constructed Wetland, James M. Waldron Mar 2007

Characterization Of Chlorinated Ethene Degradation In A Vertical Flow Constructed Wetland, James M. Waldron

Theses and Dissertations

Chlorinated solvents, including perchloroethene (PCE) and trichlorethene (TCE), are among the most common groundwater contaminants found in the United States. Once released into the environment, chlorinated solvents are extremely persistent and often require costly and lengthy remedial actions. The use of constructed wetlands has shown promise as an effective and less costly alternative for the treatment of chlorinated solvent contaminated groundwater. This study characterized and evaluated the concentration of chlorinated ethenes within a vertical flow constructed wetland, fed with PCE contaminated groundwater, at Wright-Patterson Air Force Base (WPAFB), Ohio. Chlorinated ethene concentrations were characterized within three distinct layers of the …

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Using Value-Focused Thinking To Evaluate The Use Of Innovative Stormwater Management Technologies On Air Force Installations, Jeffrey T. Falcone Mar 2007

Using Value-Focused Thinking To Evaluate The Use Of Innovative Stormwater Management Technologies On Air Force Installations, Jeffrey T. Falcone

Theses and Dissertations

Stormwater runoff occurs naturally after every storm event; however, traditional development practices have created many impervious surfaces, such as buildings, parking lots, and streets that increase runoff volume and flow rate. Conventional stormwater management practices focus on collecting runoff into centralized channels and conveying it as quickly as possible to local bodies of water. This type of conveyance system decreases the opportunity for stormwater to naturally infiltrate back into the ground. It also prevents contaminants from being naturally filtered out of stormwater flows. As a result, centralized conveyance systems can cause flooding, erosion, and terrestrial and aquatic habitat degradation. Innovative …

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Selecting Electricity Generation Sources In Remote Locations, Kelly E. Kwan Mar 2007

Selecting Electricity Generation Sources In Remote Locations, Kelly E. Kwan

Theses and Dissertations

The purpose of this research was to investigate the impact of using a decision analysis technique for the selection of an electrical generation system for remote locations. Specifically, this thesis sought to answer five research questions addressing the types of energy sources used in remote locations, the decision-making processes used to identify these sources, the types of constraints incorporated in such a process, other valued factors, and their level of importance in relation to each other. The research questions were answered through a comprehensive literature review and the 10-Step Value-Focused Thinking Process on a specific case study in the National …

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Microbial Degradation Of Fuel Oxygenates Under Aerobic Conditions, John M. Dietz Mar 2007

Microbial Degradation Of Fuel Oxygenates Under Aerobic Conditions, John M. Dietz

Theses and Dissertations

This research determined the rate and extent of aerobic biodegradation of fuel oxygenates ethyl tert butyl ether (ETBE), tert amyl methyl ether (TAME), and ethyl alcohol (ethanol). Biodegradation was measured using gas chromatography (GC), respirometry, and biochemical oxygen demand (BOD) tests. Additionally, the research determined the effects of toluene on degradation rates. This microcosm study used a microbial consortium obtained from a petroleum refinery wastewater treatment facility. Respirometry data were collected from chambers containing pure oxygenates, or oxygenate/toluene mixtures. Samples were withdrawn periodically for GC analysis. Aerobic conditions were maintained in the chambers at all times. The five-day BOD test …

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Optimizing The Prioritization Of Natural Disaster Recovery Projects, Jason M. Aftanas Mar 2007

Optimizing The Prioritization Of Natural Disaster Recovery Projects, Jason M. Aftanas

Theses and Dissertations

Prioritizing reconstruction projects to recover a base from a natural disaster is a complicated and arduous process that involves all levels of leadership. The project prioritization phase of base recovery has a direct affect on the allocation of funding, the utilization of human resources, the obligation of projects, and the overall speed and efficiency of the recovery process. The focus of this research is the development of an objective and repeatable process for optimizing the project prioritization phase of the recovery effort. This work will focus on promoting objectivity in the project prioritizing process, improving the communication of the overall …

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Quantification Of Risk For Usaf Fire And Emergency Services Flights As A Result Of Shortage In Manpower, Timothy D. Dalby Mar 2007

Quantification Of Risk For Usaf Fire And Emergency Services Flights As A Result Of Shortage In Manpower, Timothy D. Dalby

Theses and Dissertations

The United States Air Force (USAF) is currently experiencing a period of high operations tempo and overseas deployments have become frequent. These deployments will leave home installations short manned. Some amount of risk is incurred by the home installation as a result of the short manning. For an organization, such as an USAF Fire and Emergency Services (FES) flight, whose primary responsibility is the protection of life and property, the incurred risk could be catastrophic. Still no attempt has been made to quantify risk in terms of manpower for the USAF FES flights. The primary purpose of this research was …

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A Decision Model For Selecting Energy Efficient Technologies For Low -Sloping Roof Tops Using Value-Focused Thinking, Michael J. Mccourt Mar 2007

A Decision Model For Selecting Energy Efficient Technologies For Low -Sloping Roof Tops Using Value-Focused Thinking, Michael J. Mccourt

Theses and Dissertations

The Air Force has a large inventory of low-sloping built up roofs (BURs) and millions of dollars are spent each year retrofitting these systems. The DOD has been directed to reduce non-renewable energy consumption by using energy-efficient technologies. These two details present a great opportunity to use the open roof space to install energy-efficient roofing technologies. The purpose of this research is to provide Air Force decision makers with a tool to assist them in deciding what roofing technologies should be installed on facilities. Value Focused-Thinking is the methodology used to construct the model, in which values were used, instead …

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A Value-Focused Thinking Model For The Selection Of The Best Rigid Pavement, Partial-Depth Spall Repair Material, Benjamin G. Speer Mar 2007

A Value-Focused Thinking Model For The Selection Of The Best Rigid Pavement, Partial-Depth Spall Repair Material, Benjamin G. Speer

Theses and Dissertations

Concrete spalls on airfield pavements generate foreign object debris (FOD) that is damaging to aircraft engines, and may damage landing gear by roughening of the pavement surface. Repairing spalled concrete on aging and deteriorating airfields is essential for its safe operational use. Picking the best repair material from many products on the commercial market is difficult. There is wide variation on material properties, and good performance on certain criteria is critical to constructing long lasting repairs. Since there is currently no procedure for Air Force decision-makers to select the best rigid-pavement repair material, a model was created using Value-Focused Thinking …

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Class Viiia Materiel: What Problems Were Encountered Transiting Oif Air Transshipment Nodes?, Jessica L. Buck Mar 2007

Class Viiia Materiel: What Problems Were Encountered Transiting Oif Air Transshipment Nodes?, Jessica L. Buck

Theses and Dissertations

Medical cargo (Class VIIIA) is critical to the success of the United States military stationed across the globe; therefore, the military must successfully ship its Class VIIIA materiel to the Warfighter. The shipping and handling of the time and temperature sensitive Class VIIIA materiel is a complex process. Since the initial stages of Operation IRAQI FREEDOM (OIF) the medical field has complained about Class VIIIA materiel arriving unserviceable to the final destination. Unserviceable materiel includes items that expired over time and items that expired from exposure to temperatures outside of their allowable range. This thesis focused on one possible area …

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Commercial Firm Training Practices Versus Aerial Port Hazardous Cargo Frustration, Jill L. Maynard Mar 2007

Commercial Firm Training Practices Versus Aerial Port Hazardous Cargo Frustration, Jill L. Maynard

Theses and Dissertations

The military is dependent on commercial vendors to augment their supply system, to include hazardous materials. Hazardous materials must be packaged and labeled differently than general cargo for shipment in the defense transportation system. Previous research has shown there is an increase in frustration levels at Aerial Ports of Embarkation. The reasons for frustration range from minor discrepancies to improperly completed shipping documents. This research investigates if commercial companies are a cause of the frustration problems. A case study methodology was used to investigate training practices of companies that had frustrated hazardous cargo at either Charleston or Dover Aerial Ports. …

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Determining Logistics Ground Support Manpower Requirements For A Reusable Military Launch Vehicle, Sydney C. Michalski Mar 2007

Determining Logistics Ground Support Manpower Requirements For A Reusable Military Launch Vehicle, Sydney C. Michalski

Theses and Dissertations

Successful space-based technologies like satellite imagery and GPS have increased military demand for a rapid-response launch capability. AF Space Command's Operationally Responsive Spacelift program was developed to ensure that the AF has the capability to launch a payload into orbit within hours of a tasking notification, and requires development of a new space launch vehicle. The Reusable Military Launch Vehicle (RMLV) is currently in the design phase. The AF Research Laboratory sponsored development of the MILEPOST simulation model in order to assess the turnaround time, and thus responsiveness, of various design alternatives. The focus of this thesis is to improve …

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An Analysis Of Robust Workforce Scheduling Models For A Nurse Rostering Problem, Paul K. Tower Mar 2007

An Analysis Of Robust Workforce Scheduling Models For A Nurse Rostering Problem, Paul K. Tower

Theses and Dissertations

Disruptions impacting workforce schedules can be costly. A 1999 study of the United Kingdom's National Health Service estimated that as much as 4% of the total resources spent on staffing were lost to schedule disruptions like absenteeism. Although disruptions can not be eliminated, workforce schedules can be improved to be more responsive to disruptions. One key area of study that has expanded over the past few years is the application of traditional scheduling techniques to re-rostering problems. These efforts have provided methods for responding to schedule disruptions, but typically require deviations to the disrupted schedule. This thesis examines five workforce …

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Critical Infrastructure Rebuild Prioritization Using Simulation Optimization, Namsuk Cho Mar 2007

Critical Infrastructure Rebuild Prioritization Using Simulation Optimization, Namsuk Cho

Theses and Dissertations

This thesis examines the importance of a critical infrastructure rebuild strategy following a terrorist attack or natural disaster such as Hurricane Katrina. Critical infrastructures are very complex and dependent systems in which their re-establishment is an essential part of the rebuilding process. A rebuild simulation model consisting of three layers (physical, information, and spatial) captures the dependency between the six critical infrastructures modeled. We employ a simulation optimization approach to evaluate rebuild prioritization combinations with a goal of minimizing the time needed to achieve an acceptable rebuild level. We use a simulated annealing heuristic as an optimization technique that works …

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Classifying Failing States, Nathan E. Nysether Mar 2007

Classifying Failing States, Nathan E. Nysether

Theses and Dissertations

The US is heavily involved in the first major war of the 21st Century -- The Global War on Terror (GWOT). As with any militant group, the foundation of the enemy's force is their people. There are two primary strategies for defeating the terrorists and achieving victory in the GWOT. First, we must root out terrorists where they live, train, plan, and recruit and attack them militarily. Second, we must suffocate them by cutting off the supply of new soldiers willing to choose aggression or even death over their current life. This thesis helps to achieve these objectives by applying …

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A Multi-Objective Decision-Making Model For Resources Allocation In Humanitarian Relief, Seungbae Park Mar 2007

A Multi-Objective Decision-Making Model For Resources Allocation In Humanitarian Relief, Seungbae Park

Theses and Dissertations

This thesis addresses the critical resource allocation in the initial days of a disaster relief operation. One of the most important and essential components of relief operations is the allocation of scarce resources to accomplish the relief efforts. Every operation for disaster relief needs various critical resources whether they are personnel, equipment, supplies, or simply finances. Several research efforts for disaster relief have suggested methods to allocate scarce resources across a variety of competing objectives and programs in a disaster relief operation. Many of those efforts focused on optimizing a mathematical programming model subject to budget constraints. However, capturing the …

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A Future-Based Risk Assessment For The Survivability Of Long Range Strike Systems, William D. Heuck Jr. Mar 2007

A Future-Based Risk Assessment For The Survivability Of Long Range Strike Systems, William D. Heuck Jr.

Theses and Dissertations

The United States Air Force today faces the challenge of allocating development resources to prepare for future force projection requirements. In particular, the Air Force's core competency of Global Attack implies a future capability that can quickly and successfully deliver combat effects anywhere in the world with impunity. Understanding that the future threat environment is dynamic and that continued advancements by adversaries will likely degrade the technical superiority of today's weapon systems, the need arises for a planning model to direct development funding to areas with the greatest probability of successfully defending the strike vehicle of 2035. Examining this problem …

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On-Demand Key Distribution For Mobile Ad-Hoc Networks, Daniel F. Graham Mar 2007

On-Demand Key Distribution For Mobile Ad-Hoc Networks, Daniel F. Graham

Theses and Dissertations

Mobile ad-hoc networks offer dynamic portable communication with little or no infrastructure. While this has many benefits, there are additional shortcomings specific to wireless communication that must be addressed. This research proposes gossip-based on-demand key distribution as a means to provide data encryption for mobile ad-hoc networks. This technique uses message keys to avoid encrypting and decrypting a message at every node. Other optimizations used include secure channel caching and joint rekey messages. The use of gossip makes the scheme robust to node failure. Experimental results show only a 15% increase in end-to-end delay with a node failure rate of …

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An Analysis Of The Military Retirement System: How Does Retirement Return Influence Retention?, Derren P. Burrell Mar 2007

An Analysis Of The Military Retirement System: How Does Retirement Return Influence Retention?, Derren P. Burrell

Theses and Dissertations

The cost of the current Department of Defense (DoD) defined-benefit retirement plan has long been a source of consternation within Congress and the DoD (Freedberg, 1999:35). Billed as being too costly in the private sector, many firms have elected to switch from defined benefit plans to defined contribution plans, most often a 401K retirement plan (Chassen, 1990:18). This thesis attempts to capture the effect of the current military retirement plan on rates of retention. The goal of this study is to be used as a tool should the Department of Defense decide to move from a defined-benefit plan to a …

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The Impact Of Ethnic Identity On Student Achievement In China: A Meta Analysis, Xinyi Wu Feb 2007

The Impact Of Ethnic Identity On Student Achievement In China: A Meta Analysis, Xinyi Wu

Theses and Dissertations

There have been concerns about low educational achievement of ethnic minority students in China. Previous studies have explored this area, especially in regard to the relationship between economic backwardness and achievement. However, a new field of study examines ethnic identity being considered as a cause of low achievement. This study is to use meta-analysis to determine the aggregate results of current research on the effects of self-identity on ethnic minority students and their achievement in China. The literature has been collected through searching library holdings, and online electronic resource search. Different levels of identity construction are discussed. This thesis concludes …

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Analysis Using Smoothing Via Penalized Splines As Implemented In Lme() In R, John R. Howell Feb 2007

Analysis Using Smoothing Via Penalized Splines As Implemented In Lme() In R, John R. Howell

Theses and Dissertations

Spline smoothers as implemented in common mixed model software provide a familiar framework for estimating semi-parametric and non-parametric models. Following a review of literature on splines and mixed models, details for implementing mixed model splines are presented. The examples use an experiment in the health sciences to demonstrate how to use mixed models to generate the smoothers. The first example takes a simple one-group case, while the second example fits an expanded model using three groups simultaneously. The second example also demonstrates how to fit confidence bands to the three-group model. The examples use mixed model software as implemented in …

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The Tragic Consequences Of Societal And Cultural Memory: William Shakespeare And Arthur Miller, Leslie A. Werden Feb 2007

The Tragic Consequences Of Societal And Cultural Memory: William Shakespeare And Arthur Miller, Leslie A. Werden

Theses and Dissertations

This dissertation argues that tragedy occurs not to a great man or a common man, but to the family left behind to confront the societal and cultural implications of the manipulated memories they have inherited. Using Chris Hedge's book War is a Force that Gives Us Meaning, I investigate how storytelling and legacy are passed along to family members who have been affected by war. Shakespeare's Titus Andronicus and Miller's All My Sons suddenly seem very similar: both plays have fathers who lost sons, which is tragic in itself. The deeper psychological tragedy occurs, however, as the fathers, in order …

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University Of North Dakota And Its Nine Peer Institutions: Governance Structure And Operational Comparisons, Laura M. Driscoll Feb 2007

University Of North Dakota And Its Nine Peer Institutions: Governance Structure And Operational Comparisons, Laura M. Driscoll

Theses and Dissertations

Abstract Not Available

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Stratification Of Southern Georgia Streams For Rapid Bioassessment Focusing On Differences In Structure And Function Of Black Water And Clear Water Streams, Salini Pradeep Pillai Feb 2007

Stratification Of Southern Georgia Streams For Rapid Bioassessment Focusing On Differences In Structure And Function Of Black Water And Clear Water Streams, Salini Pradeep Pillai

Theses and Dissertations

As part of a rapid bioassessment project for the state of Georgia, relatively unimpaired reference streams and impaired sites were sampled for biological, chemical and physical parameters, and macroinvertebrates were identified. The metrics, biological, physical and chemical metrics, were selected using Ecological Data Application System Version 3.3.2k (EDAS). Discrimination efficiency and correlations were performed to determine the best metrics that separated impaired streams from reference streams and later on to form the index of stream water quality. Principal components analysis of the selected metrics showed that some of the blackwater reference streams and clearwater reference streams are randomly placed over …

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Effects Of Rumination On Internal And External Locus Of Control, Michael R. Sterling Jan 2007

Effects Of Rumination On Internal And External Locus Of Control, Michael R. Sterling

Theses and Dissertations

The primary goal of this study was to explore the relationship between rumination, locus of control, and depressive symptomology. The current project utilized a survey methodology, in which 54 undergraduate students were required to complete the Response Style Questionnaire (RSQ), the Rotter Locus of Control Scale (LOC), and the Beck Depression Inventory II (BDI-II). Previous literature has not examined the relationship between rumination and locus of control. It was hypothesized that ruminative thought and external locus of control would be positively correlated. Correlations were run between the scores of each questionnaire, as well as gender of the participants. Results indicated …

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An Investigation Of Methods To Homogeneously Entrain And Suspend Abrasive Particles In A Low Pressure Dental Water Jet, Michael Sean Grygla Jan 2007

An Investigation Of Methods To Homogeneously Entrain And Suspend Abrasive Particles In A Low Pressure Dental Water Jet, Michael Sean Grygla

Theses and Dissertations

During the past several decades, the water jet cutting concept has developed from a novel concept into a well-accepted machine cutting tool. With the addition of abrasive particles and the improvement of high pressure pumps, the water jet stream is currently capable of cutting through metal, concrete, and composite materials. Water jet systems have been utilized at a wide range of different pressures. Research performed at Brigham Young University has revealed that low pressure water jets have the ability to cut human teeth. Experiments have shown that when abrasive particles are added to the water jet stream, an greater amount …

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Neurophysiologic And Behavioral Measures Of Phonetic Perception In Adult Second Language Speakers Of Spanish, Jaden D. Hellewell Jan 2007

Neurophysiologic And Behavioral Measures Of Phonetic Perception In Adult Second Language Speakers Of Spanish, Jaden D. Hellewell

Theses and Dissertations

Infants 6-8 months old are able to identify nearly every speech sound contrast on which they have been tested, regardless of whether that contrast represents an across-category (two different phonemes) phonetic change in their native language or not. A child's ability to identify non-native consonant contrasts greatly diminishes by 11-12 months of age. The present study examined speech sound discrimination in three groups of listeners. Adult second language (L2) listeners of Spanish were compared with native English listeners with no knowledge of Spanish and native Mexican listeners to determine if they would show the ability to discriminate phonetic distinctions that …

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An Analysis Of The Subjective Socioeconomic Scale Among Hispanic Immigrants And Caucasians, Mathew Glen Bowden Jan 2007

An Analysis Of The Subjective Socioeconomic Scale Among Hispanic Immigrants And Caucasians, Mathew Glen Bowden

Theses and Dissertations

Subjective socioeconomic status (SES) has previously been shown to be correlated with a large number of health measures. In this study, the subjective SES measure is modified and translated to measure childhood SES. The subjective SES scale is examined in a participant's hometown, community, and nation. Both an immigrant Hispanic and a Caucasian sample were studied (31 Hispanic males; 42 Hispanic females; 38 Caucasian males, 40 Caucasians females). Childhood SES was the most significant predictor of self-reported health in both sample groups.

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Is Marriage Education Effective? A Meta-Analytic Review Of Marriage Education Programs, Elizabeth Brinton Fawcett Jan 2007

Is Marriage Education Effective? A Meta-Analytic Review Of Marriage Education Programs, Elizabeth Brinton Fawcett

Theses and Dissertations

In the past few decades, several meta-analytic studies have attempted to answer the question: Is marriage education effective (Carroll & Doherty, 2003; Halford, Markman, Kline & Stanley, 2003; Reardon-Anderson, Stagner, Macomber, & Murray, 2004)? However, previous meta-analytic studies have been somewhat limited in their conclusions because they have reviewed a narrow portion of the marriage education spectrum (e.g. premarital education only, Carroll & Doherty, 2003), because they focused only on one particular program (e.g, Couples Communication, Butler & Wampler, 1999), because they failed to differentiate marital therapy from marital education programs (Reardon-Anderson et al., 2005), or because they excluded much …

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Role Of Trauma In Social-Cognitive Adjustment Strategies And Moral Disengagement Among African-American Urban Youth, Kendell Lamonte Coker Jan 2007

Role Of Trauma In Social-Cognitive Adjustment Strategies And Moral Disengagement Among African-American Urban Youth, Kendell Lamonte Coker

Theses and Dissertations

The role of trauma has been implicated in the etiology of juvenile delinquency (Esbensen & Huizinga, 1991; Dulmus, 2003). This is especially pronounced among inner city minority youth. Traumatic experiences can hinder an adolescent's social-cognitive development, prevent the use of adequate coping mechanisms and cognitive processes, such as social problem solving, and lead youth to disengage their moral controls (Ng-Mak, Salzinger, Feldman, & Stueve, 2002). The purpose of this study was to explore the effects of trauma and adjustment strategies among African American urban youth and how moral disengagement can be averted via mediation by the use of social problem …

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Analysis Of Heart Rate Variability Signal Using State Space Based Methods, Mihails Tihonciks Jan 2007

Analysis Of Heart Rate Variability Signal Using State Space Based Methods, Mihails Tihonciks

Theses and Dissertations

In this study, we try to determine validity of the several different measures applied to the nonlinear HRV data. There were many studies done using traditional methods of Approximate Entropy, Correlation Dimension, Lyapunov exponents and recurrence plots. While employing some of these methods, we also decided to use Support Vector Machines. This method of analysis is quite new to the world of nonlinear data. We obtained data from five different groups of young healthy adults: spontaneous breathing group (Normal), metronomic breathing group (Metron) and elite athletes (Ironman), as well as two groups of people participating in specific traditional forms of …

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