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Infinite Product Group, Keith G. Penrod Jul 2007

Infinite Product Group, Keith G. Penrod

Theses and Dissertations

The theory of infinite multiplication has been studied in the case of the Hawaiian earring group, and has been seen to simplify the description of that group. In this paper we try to extend the theory of infinite multiplication to other groups and give a few examples of how this can be done. In particular, we discuss the theory as applied to symmetric groups and braid groups. We also give an equivalent definition to K. Eda's infinitary product as the fundamental group of a modified wedge product.

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Probing For Reasons: Presentations, Questions, Phases, Kellyn Nicole Farlow Jul 2007

Probing For Reasons: Presentations, Questions, Phases, Kellyn Nicole Farlow

Theses and Dissertations

This thesis reports on a research study based on data from experimental teaching. Students were invited, through real-world problem tasks that raised central conceptual issues, to invent major ideas of calculus. This research focuses on work and thinking of the students, as they sought to build key ideas, representations and compelling lines of reasoning. This focus on the students' and their agency as learners has brought about a new development of the psychological and logical perspectives, as well as, highlighted students' choices in academic and social roles. Such choices facilitated continued learning among these students.

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A Geometry-Based Motion Planner For Direct Machining And Control, Robert M. Cheatham Jul 2007

A Geometry-Based Motion Planner For Direct Machining And Control, Robert M. Cheatham

Theses and Dissertations

Direct Machining And Control (DMAC) is a new method of controlling machine tools directly from process planning software. A motion planning module is developed for the DMAC system that operates directly off path geometry without pre-tessellation. The motion planner is developed with the intent to process Bezier curves. The motion planning module includes a deterministic predictor-corrector-type curve interpolator, a dynamics limiting module, and a two-pass jerk-limited speed profiling algorithm. The methods are verified by machining an automotive surface in a clay medium and evaluating the resultant machine dynamics, feed rate, and chordal error throughout the machining process.

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The Main Challenges That A Teacher-In-Transition Faces When Teaching A High School Geometry Class, Greg Brough Henry Jul 2007

The Main Challenges That A Teacher-In-Transition Faces When Teaching A High School Geometry Class, Greg Brough Henry

Theses and Dissertations

During a semester-long action research study, the author attempted to implement a standards-based approach to teaching mathematics in a high school geometry class. Having previously taught according to a more traditional manner, there were many challenges involved as he made this transition. Some of the challenges were related to Geometry and others were related to the standards-based approach in general. The main challenges that the author encountered are identified and discussed. A plan of action for possible solutions to these challenges is then described.

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Autonomic Product Development Process Automation, John E. Daley Jul 2007

Autonomic Product Development Process Automation, John E. Daley

Theses and Dissertations

Market globalization and mass customization requirements are forcing companies towards automation of their product development processes. Many task-specific software solutions provide localized automation. Coordinating these local solutions to automate higher-level processes requires significant software maintenance costs due to the incompatibility of the software tools and the dynamic nature of the product development environment. Current automation methods do not provide the required level of flexibility to operate in this dynamic environment. An autonomic product development process automation strategy is proposed in order to provide a flexible, standardized approach to product development process automation and to significantly reduce the software maintenance costs …

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Hardware Support For A Configurable Architecture For Real-Time Embedded Systems On A Programmable Chip, Spencer W. Isaacson Jul 2007

Hardware Support For A Configurable Architecture For Real-Time Embedded Systems On A Programmable Chip, Spencer W. Isaacson

Theses and Dissertations

Current FPGA technology has advanced to the point that useful embedded SoPCs can now be designed. The Real Time Processor (RTP) project at Brigham Young University leverages the advances in FPGA technology with a system architecture that is customizable to specific applications. A simple real-time processor has been designed to provide support for a hardware-assisted real-time operating system providing fast context switches. As part of the hardware RTOS, the following have been implemented in hardware: scheduler, register banks, mutex, semaphore, queue, interrupts, event, and others. A novel circuit called the Task-Resource Matrix has been created to allow fast inter/intra processor …

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Potential Energy Surfaces For Small Alcohol Dimers. Ii. Propanol, Isopropanol, T-Butanol, And Sec-Butanol, Richard L. Rowley, Christopher M. Tracy, Tapani A. Pakkanen Jul 2007

Potential Energy Surfaces For Small Alcohol Dimers. Ii. Propanol, Isopropanol, T-Butanol, And Sec-Butanol, Richard L. Rowley, Christopher M. Tracy, Tapani A. Pakkanen

Faculty Publications

Potential energy landscapes for homogeneous dimers of propanol, isopropanol, tert-butanol, and sec-butanol were obtained using 735 counterpoise-corrected energies at the MP2/6-311+G(2df,2pd) level. The landscapes were sampled at 15 dimer separation distances for different relative monomer geometries, or routes, given in terms of the yaw, pitch, and roll of one monomer relative to the other and the spherical angles between the two monomer centers (taken as the C atom attached to the O). The resultant individual energy surfaces and their complex topographies were also regressed using a site-site pair potential model using a modified Morse potential that provides a mathematically simple …

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Applying Toulmin's Argumentation Framework To Explanations In A Reform Oriented Mathematics Class, Jennifer Alder Brinkerhoff Jul 2007

Applying Toulmin's Argumentation Framework To Explanations In A Reform Oriented Mathematics Class, Jennifer Alder Brinkerhoff

Theses and Dissertations

This study looks at conceptual explanations given in a reform-oriented mathematics class for preservice secondary mathematics teachers and extends Toulmin's argumentation framework to account for some of the complexities of the explanations given by these students. This study explains the complexities that arose in applying Toulmin's framework to explanations and extends the framework by accounting for the features of conceptual explanations. The complexities of these explanations are that they are made up of multiple arguments that build on each other to reach a final conclusion and that they are also dependant upon the social aspects of the class in which …

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Or Best Offer: A Privacy Policy Negotiation Protocol, Daniel David Walker Jul 2007

Or Best Offer: A Privacy Policy Negotiation Protocol, Daniel David Walker

Theses and Dissertations

Users today are concerned about how their information is collected, stored and used by Internet sites. Privacy policy languages, such as the Platform for Privacy Preferences (P3P), allow websites to publish their privacy practices and policies in machine readable form. Currently, software agents designed to protect users' privacy follow a "take it or leave it" approach when evaluating these privacy policies. This approach is inflexible and gives the server ultimate control over the privacy of web transactions. Privacy policy negotiation is one approach to leveling the playing field by allowing a client to negotiate with a server to determine how …

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Pipe Diagrams For Thompson's Group F, Aaron L. Peterson Jul 2007

Pipe Diagrams For Thompson's Group F, Aaron L. Peterson

Theses and Dissertations

We review the definition and standard description of Thompson's Group F. We define the set of pipe diagrams and show that this set forms a group isomorphic to F. We use pipe diagrams to prove two theorems about giving a minimal representation for an arbitrary element of F.

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Development Of A Mevva Based Beryllium-7 Plasma Source, David K. Olson Jul 2007

Development Of A Mevva Based Beryllium-7 Plasma Source, David K. Olson

Theses and Dissertations

We have designed a new type of plasma gun ion source for a Malmberg-Penning trap based on Metal Vapor Vacuum Arc (MeVVA) ion source designs. Our primary intent with this MeVVA-type source is to create a confinable beryllium-7 (7-Be) plasma. 7-Be is a peculiar isotope due to its varying radioactive decay half-life in different electro-chemical configurations. It is also found in an unexpected abundance at high altitudes of the Earth's atmosphere. It is possible ioniziation affects the radioactivity of the isotope, partly explaining this discrepancy with atmospheric models. The short half-life of 7-Be requires us to replace the sample inside …

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A Modified Cluster-Weighted Approach To Nonlinear Time Series, Mark Ballatore Lyman Jul 2007

A Modified Cluster-Weighted Approach To Nonlinear Time Series, Mark Ballatore Lyman

Theses and Dissertations

In many applications involving data collected over time, it is important to get timely estimates and adjustments of the parameters associated with a dynamic model. When the dynamics of the model must be updated, time and computational simplicity are important issues. When the dynamic system is not linear the problem of adaptation and response to feedback are exacerbated. A linear approximation of the process at various levels or “states” may approximate the non-linear system. In this case the approximation is linear within a state and transitions from state to state over time. The transition probabilities are parametrized as a Markov …

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Chateaubriand's René As A Philosophical Reaction To The Enlightenment And Early Romantic Sentiment, Christopher Martin Flood Jul 2007

Chateaubriand's René As A Philosophical Reaction To The Enlightenment And Early Romantic Sentiment, Christopher Martin Flood

Theses and Dissertations

For over 200 years “René&rqduo; Chateaubriand's short fictional interlude in his grand argument for the restoration of Christianity after the French Revolution, has been read as the founding text of the French Romantic movement. While this text did in fact serve to define many of the characteristics of French Romantic literature, simply labeling it as such is anachronistic and obscures the more profound philosophical and theological claims Chateaubriand was actually attempting to illustrate. After an examination of the discrepancy between the author's intentions and the general perception, this study will briefly consider some of the traditional readings of “René” specifically …

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Synthesis And Antiviral Evaluation Of Some 3'-Carboxymethyl-3'-Deoxyadenosine Derivatives, Houguang Shi Jul 2007

Synthesis And Antiviral Evaluation Of Some 3'-Carboxymethyl-3'-Deoxyadenosine Derivatives, Houguang Shi

Theses and Dissertations

3'-Carboxymethyl-3'-deoxyadenosine derivatives were prepared from 2'-O-TBDMS-3'-deoxy-3'-[(ethoxycarbonyl)methyl]adenosine (1) via simple and efficient procedures. Conversion of 1 to 5'-azido-2'-O-TBDMS-3', 5'-dideoxy -3'-[(ethoxycarbonyl) methyl] adenosine (4) was accomplished via a novel one-pot method employing 5'-activation (TosCl) followed by efficient nucleophilic displacement with tetramethylguanidinium azide. Compound 4 was converted to a 5'-[(N-methylcarbamoyl)amino] derivative (5) via one-pot reduction/acylation employing H2/Pd-C followed by treatment with p-nitrophenyl N-methylcarbamate. The latter step of this two-step process required an efficient source of p-nitrophenyl N-methylcarbamate, thus a highly efficient new method for preparing p-nitrophenyl N-alkylcarbamate was developed. N6-phenylcarbamoyl groups were introduced by treatment with phenylisocyanate, and an efficient new method for …

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A Comparative Simulation Study Of Robust Estimators Of Standard Errors, Natalie Johnson Jul 2007

A Comparative Simulation Study Of Robust Estimators Of Standard Errors, Natalie Johnson

Theses and Dissertations

The estimation of standard errors is essential to statistical inference. Statistical variability is inherent within data, but is usually of secondary interest; still, some options exist to deal with this variability. One approach is to carefully model the covariance structure. Another approach is robust estimation. In this approach, the covariance structure is estimated from the data. White (1980) introduced a biased, but consistent, robust estimator. Long et al. (2000) added an adjustment factor to White's estimator to remove the bias of the original estimator. Through the use of simulations, this project compares restricted maximum likelihood (REML) with four robust estimation …

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The Smallest Base And Precious Metal Deposits In The World: Vapor Transport And Deposition Of Co-Cu-Sn-Ag Alloys In Vesicles, Elizabeth Adele Outdoor Hunter Jul 2007

The Smallest Base And Precious Metal Deposits In The World: Vapor Transport And Deposition Of Co-Cu-Sn-Ag Alloys In Vesicles, Elizabeth Adele Outdoor Hunter

Theses and Dissertations

Metallic bronze-Co-Ag alloys ranging from1-90 µm have been discovered in bomb and lava vesicles from the mafic volcanoes of Kilauea in Hawaii and Vesuvius, Stromboli and Etna in Italy. It is inferred that the metals for these alloys were transported (in part) as chloride complexes, and that the metal ratios in the alloys may be a function of S/Cl. Alloy compositions in each system are extremely heterogeneous with Co concentrations from 1% to 94%, Cu from 2% to 89%, Sn from 1% to 22% and Ag from 0.5% to 42%. Maximum abundances (in wt%) of other trace or minor elements …

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In Search Of Copia: Using Rhetoric To Teach Creative Writing, Ryan Solomon Jul 2007

In Search Of Copia: Using Rhetoric To Teach Creative Writing, Ryan Solomon

Theses and Dissertations

James Berlin, in his book Rhetoric and Reality, points out that our disparate epistemologies lead to inevitable classroom practices, which mean that different epistemologies impact our pedagogical approach and enforce certain views about the role and function of writing in classrooms. This thesis highlights the impact of Romantic beliefs about writing on creative writing pedagogy, as well as exploring how those beliefs hamper the critical function of the workshop. Romantic beliefs have enforced the idea that talent and genius is most important in creative writing, and that writing is spontaneous, organic, original, and expressive. Because of this, many creative writing …

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Extreme Ultraviolet Polarimetry With Laser-Generated High-Order Harmonics, Nicole Brimhall Jul 2007

Extreme Ultraviolet Polarimetry With Laser-Generated High-Order Harmonics, Nicole Brimhall

Theses and Dissertations

We developed an extreme ultraviolet (EUV) polarimeter, which employs laser-generated high-order harmonics as the light source. This relatively high-flux directional EUV source has available wavelengths between 8 nm and 62 nm and easily rotatable linear polarization. The polarimeter will aid researchers at BYU in characterizing EUV thin films and improving their understanding of materials for use in EUV optics. This first-time workhorse application of laser high harmonics enables polarization-sensitive reflection measurements not previously available in the EUV. We have constructed a versatile positioning system that places harmonics on the microchannel plate detector with an accuracy of 0.3 mm, which allows …

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Reservoir Characterization And Outcrop Analogs To The Navajo Sandstone In The Central Utah Thrust Belt Exploration Play, Ashley Dalrymple Jul 2007

Reservoir Characterization And Outcrop Analogs To The Navajo Sandstone In The Central Utah Thrust Belt Exploration Play, Ashley Dalrymple

Theses and Dissertations

Reservoir heterogeneity plays an important role in oil field economics and completion strategies. We herein characterize the reservoir heterogeneity of the Early Jurassic Navajo Sandstone in the Justensen Flat/Devils Canyon area of the San Rafael Swell, Utah. These outcrops are located approximately 60 kilometers (45 mi) east of the recently discovered Covenant oil field which is located in the central Utah thrust belt exploration play. The reservoir for the Covenant field is the Navajo Sandstone. This study can serve as an outcrop analogue for this developing play and other eolian reservoirs worldwide. There are eight facies within the Navajo Sandstone …

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Sensitivity To Distributional Assumptions In Estimation Of The Odp Thresholding Function, Wendy Jill Bunn Jul 2007

Sensitivity To Distributional Assumptions In Estimation Of The Odp Thresholding Function, Wendy Jill Bunn

Theses and Dissertations

Recent technological advances in fields like medicine and genomics have produced high-dimensional data sets and a challenge to correctly interpret experimental results. The Optimal Discovery Procedure (ODP) (Storey 2005) builds on the framework of Neyman-Pearson hypothesis testing to optimally test thousands of hypotheses simultaneously. The method relies on the assumption of normally distributed data; however, many applications of this method will violate this assumption. This thesis investigates the sensitivity of this method to detection of significant but nonnormal data. Overall, estimation of the ODP with the method described in this thesis is satisfactory, except when the nonnormal alternative distribution has …

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Extensible Pre-Authentication In Kerberos, Phillip L. Hellewell Jul 2007

Extensible Pre-Authentication In Kerberos, Phillip L. Hellewell

Theses and Dissertations

Organizations need to provide services to a wide range of people, including strangers outside their local security domain. As the number of users grows larger, it becomes increasingly tedious to maintain and provision user accounts. It remains an open problem to create a system for provisioning outsiders that is secure, flexible, efficient, scalable, and easy to manage. Kerberos is a secure, industry-standard protocol. Currently, Kerberos operates as a closed system; all users must be specified upfront and managed on an individual basis. This paper presents EPAK (Extensible Pre-Authentication in Kerberos), a framework that enables Kerberos to operate as an open …

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Obstacle Avoidance And Path Traversal Using Interactive Machine Learning, Jonathan M. Turner Jul 2007

Obstacle Avoidance And Path Traversal Using Interactive Machine Learning, Jonathan M. Turner

Theses and Dissertations

Recently there has been a growing interest in using robots in activities that are dangerous or cost prohibitive for humans to do. Such activities include military uses and space exploration. While robotic hardware is often capable of being used in these types of situations, the ability of human operators to control robots in an effective manner is often limited. This deficiency is often related to the control interface of the robot and the level of autonomy that control system affords the human operator. This thesis describes a robot control system, called the safe/unsafe system, which gives a human operator the …

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Define Universe And Give Two Examples: A Comparison Of Scientific And Christian Belief. By Barton E. Dahneke, Noel L. Owen Jul 2007

Define Universe And Give Two Examples: A Comparison Of Scientific And Christian Belief. By Barton E. Dahneke, Noel L. Owen

BYU Studies

Barton E. Dahneke. Define Universe and Give Two Examples: A Comparison of Scientific and Christian Belief. Palmyra, N.Y.: BDS Publications, 2006.

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Time-Varying Mimo Channels: Parametric Statistical Modeling And Experimental Results, Michael A. Jensen, Shuangquan Wang, Ali Abdi, Jari Salo, Hassan M. El-Sallabi, Jon W. Wallace, Pertti Vainikainen Jul 2007

Time-Varying Mimo Channels: Parametric Statistical Modeling And Experimental Results, Michael A. Jensen, Shuangquan Wang, Ali Abdi, Jari Salo, Hassan M. El-Sallabi, Jon W. Wallace, Pertti Vainikainen

Faculty Publications

Accurate characterization of multiple-input multiple-output (MIMO) fading channels is an important prerequisite for the design of multiantenna wireless-communication systems. In this paper, a single-bounce two-ring statistical model for the time-varying MIMO flat fading channels is proposed. In the model, both the base and mobile stations are surrounded by their own ring of scatterers. For the proposed model, a closed-form expression for the spatio-temporal cross-correlational function between any two subchannels is derived, assuming single-bounce scattering. The new analytical expression includes several key physical parameters of interest such as the mean angle-of-departure, the mean angle-of-arrival, the associated angle spreads, and the Doppler …

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A Dynamic Attribute-Based Load Shedding Scheme For Data Stream Management Systems, Amit Ahuja, Yiu-Kai D. Ng Jul 2007

A Dynamic Attribute-Based Load Shedding Scheme For Data Stream Management Systems, Amit Ahuja, Yiu-Kai D. Ng

Faculty Publications

A data stream being transmitted over a network channel with capacity less than the data transmission rate of the data stream causes sequential network problems. In this paper, we present a new approach for shedding less-informative attribute data from a data stream to maintain a data transmission rate less than the network channel capacity. A scheme for shedding attributes and their data, instead of tuples, becomes imperative in data stream load shedding, since shedding a complete tuple would lead to shedding informative attribute data along with less-informative attribute data in the tuple. Our load shedding approach handles intra-stream, as well …

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Henry George: The Theory Of Distribution In Progress And Poverty, Phillip J. Bryson Jul 2007

Henry George: The Theory Of Distribution In Progress And Poverty, Phillip J. Bryson

Faculty Publications

The core of Henry George's economic theory appeared in his most widely-read book, Progress and Poverty. On the basis of his dramatic "single tax" theory, his work became widely known and gained some avid followers who endeavored to base policy on it. But the work was also of value in George's day and interest in our day because of its economic content. George was not a part of the academic economics establishment of his day and his theory was of strictly classical methodology, but it still had much to commend it. A simple model to present his concepts in more …

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Information Consensus And Its Application In Multi-Vehicle Cooperative Control, Ella Atkins, Randal Beard, Wei Ren Jul 2007

Information Consensus And Its Application In Multi-Vehicle Cooperative Control, Ella Atkins, Randal Beard, Wei Ren

Faculty Publications

In the last two decades, advances in networking and distributed computing have facilitated a paradigm shift from large, monolithic mainframe computers to networks of less expensive, less powerful workstations. One motivation for multi-vehicle systems is to achieve the same gains for mechanically controlled systems as has been gained in distributed computation. Rather than having a single monolithic (and therefore expensive and complicated) machine do everything, the hope is that many inexpensive, simple machines, can achieve the same, or enhanced functionality, through coordination. In essence, the objective is to replace expensive complicated hardware with software and multiple copies of simple hardware. …

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Using Box-Scores To Determine A Position's Contribution To Winning Basketball Games, Gilbert W. Fellingham, C. Shane Reese, Garritt L. Page Jul 2007

Using Box-Scores To Determine A Position's Contribution To Winning Basketball Games, Gilbert W. Fellingham, C. Shane Reese, Garritt L. Page

Faculty Publications

While it is generally recognized that the relative importance of different skills is not constant across different positions on a basketball team, quantification of the differences has not been well studied. 1163 box scores from games in the National Basketball Association during the 1996-97 season were used to study the relationship of skill performance by position and game outcome as measured by point differentials. A hierarchical Bayesian model was fit with individual players viewed as a draw from a population of players playing a particular position: point guard, shooting guard, small forward, power forward, center, and bench. Posterior distributions for …

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A New Method For Treating Wells In Reservoir Simulation, Gregory M. Gessel Jun 2007

A New Method For Treating Wells In Reservoir Simulation, Gregory M. Gessel

Theses and Dissertations

A new method for formulating finite difference equations for reservoir simulation has been developed. It can be applied throughout the entire simulated reservoir or to local segments. When applied to cells containing vertical, fully penetrating, straight-line wells in a homogeneous reservoir, the resulting equations are equivalent to Peaceman's classical well equations used in most reservoir simulators today. However, when the new finite difference equations are applied to both the well-containing cells, and their neighbors, the accuracy of the simulation improves substantially. The method produces still better accuracy results when applied throughout the reservoir. Unlike the Peaceman correction, the new method …

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Development Of A Notational Analysis System To Evaluate Setting Performance In Volleyball, Nina Puikkonen Mortensen Jun 2007

Development Of A Notational Analysis System To Evaluate Setting Performance In Volleyball, Nina Puikkonen Mortensen

Theses and Dissertations

The purposes of this study were to develop a notational analysis system to evaluate volleyball setting performance independent of the actions of the hitter and to use the data to develop a Markovian transitional matrix that would make known the probabilities of specific outcomes from each setting scenario. Setting performance was analyzed based on the sets distance from the net, height of the set, and position of the set in relation to the hitter as viewed from 13 filmed competitions of a Division I intercollegiate women's volleyball team. Data from the notation of 1353 sets were used to develop a …

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