Digital Commons Network^™

Precision Control Of A Sensorless Brushless Direct Current Motor System, Matthew John Knight

School of Engineering, Computing and Mathematics Theses

Sensorless control strategies were first suggested well over a decade ago with the aim of reducing the size, weight and unit cost of electrically actuated servo systems. The resulting algorithms have been successfully applied to the induction and synchronous motor families in applications where control of armature speeds above approximately one hundred revolutions per minute is desired. However, sensorless position control remains problematic. This thesis provides an in depth investigation into sensorless motor control strategies for high precision motion control applications. Specifically, methods of achieving control of position and very low speed thresholds are investigated. The developed grey box identification …

The Classification Of Low Dimensional Nilpotent Lie Algebras, Kimberli C. Tripp

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Nilpotent Lie algebras are the fundamental building blocks for generic (not semi-simple) Lie algebras. In particular, the classification of nilpotent algebras is the first step in classifying and identifying solvable Lie Algebras. The problem of classifying nilpotent Lie algebras was first studied by Umlauf [9] in 1891. More recently, classifications have been given up to dimension six using different techniques by Morosov (1958) [7], Skjelbred and Sund (1977) [8], and up to dimension five by Dixmier (1958) [2]. Using Morosov's method of classification by maximal abelian ideals, Winternitz reproduced the Morosov classification obtaining different canonical forms for the algebras. The …

A Recommendation For Determining The Efficacy Of Weight Removal Estimates For The Pacific Cod Longline Cdq Fishery, Anna L. Furniss

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

In January 2000, the Alaska Department of Community and Economic Development contacted the National Marine Fisheries Service (NMFS) regarding concerns over the methods used to determine catch estimates for the Pacific Cod Community Development Quota (CDQ) fishery. Currently, NMFS determines catch estimates for the Pacific Cod CDQ fishery based on the data collected by observers from the North Pacific Groundfish Observer Program (NPGOP).

Observer estimates for catch are based on the random sampling methods for a longline fishing vessel as described in the North Pacific Groundfish Observer Manual. These sampling methods provide an official total catch (OTC) estimate for each …

Variables Related To The Successful Completion Of The First Course In Business Calculus At Three Jamaican Universities, Martin Nkhrama Richards

Dissertations

Problem. Many students at all levels of the education system in Jamaica perform poorly at mathematics. In particular, the results of both the Caribbean Examinations Council and Business Calculus 1 at the university level have reflected a declining trend in mathematics performance in recent years. Consequently, this study sought to investigate the variables related to the successful completion of the first course in business calculus at Jamaican universities. To this end, the study looked at perceptions of students and their professors regarding students' cognitive, affective, and professor effectiveness variables impacting success.

Method. The sample for this study consisted of 389 …

Why Tax The Rich? Efficiency, Equity, And Progressive Taxation, Reuven S. Avi-Yonah

Reviews

In Greek mythology, Atlas was a giant who carried the world on his shoulders. In Ayn Rand’s 1957 novel Atlas Shrugged, Atlas represents the “ prime movers”—the talented few who bear the weight of the world’s economy.1 In the novel, the prime movers go on strike against the oppressive burden of excessive regulation and taxation, leaving the world in disarray and demonstrating how indispensable they are to the rest of us (the “second handers” ).

Thirteen Ways Of Looking At The Law, Bert I. Huang

Faculty Scholarship

I was of three minds
Like a tree
In which there are three blackbirds.

The emergence of external disciplines within legal scholarship seems to have fractured its intellectual focus. Technical and specialized academic writing, moreover, appears to be drifting ever farther from the theaters of legal action. Judge Richard Posner's latest book of essays, Frontiers of Legal Theory, challenges such perceptions: Even as it celebrates the breadth of interdisciplinary legal scholarship, it seeks coherence among myriad methodologies. Even as it delights in the abstract constructs of social science, it emphasizes their practical impact. And as one might expect of Judge …

Exemplary Bilingual Teachers In Puerto Rico: A Multiple-Case Study, Aurea Laracuente Araújo

Dissertations

Problem. Within a context of inadequate pre-service training, insufficient administrative support, and an ambivalent social environment regarding the teaching of ESL in Puerto Rico, a number of conscientious bilingual teachers try to overcome the odds of the system and have an impact on students' ability to speak English. Some even become exemplary teachers. How do they learn to meet so many expectations successfully in spite of real short comings found in their job, and how do they acquire the skills and competencies necessary to be exemplary bilingual teachers in Puerto Rico?

Method. A qualitative multiple-case study design was …

Teaching About Religion In Public Schools, Kent Greenawalt

Faculty Scholarship

Two of the twentieth century's most controversial Supreme Court decisions held that public schools could not sponsor devotional prayer and Bible reading as part of their educational program. Yet, whether to begin school with a few minutes of devotional practice matters far less than what schools teach about religion, one of the most nettlesome issues of church-state relations in a liberal democracy. This question has received comparatively little attention from constitutional lawyers, because the Supreme Court has declared that teaching about religion is acceptable and has not addressed challenges to programs educators have labeled in this way. Many citizens, of …

Modeling Phytoplankton Production: Problems With The Eppley Curve And An Empirical Alternative, Mark J. Brush, John W. Brawley, Scott W. Nixon, James N. Kremer

Graduate School of Oceanography Faculty Publications

Papers reporting the results of dynamic simulation models of aquatic ecosystems tend to show predicted concentrations of the state variables. The phytoplankton compartment is typically represented as predicted biomass, expressed as the concentration of chlorophyll a, particulate carbon, or particulate nitrogen. While computed values of phytoplankton biomass generally agree with observations, many of these same models significantly underestimate primary production. Existing simulation models often base the calculation of primary production on the Eppley curve, which sets the maximum daily phytoplankton growth rate as a function of temperature. Despite the apparent wide applicability of the Eppley curve, an increasing number …

Money, Credit, And Banking In Colonial And Postcolonial West Africa, Akanmu G. Adebayo

Faculty Articles

Scholarship in African economic history has been dominated by a wave of revisionism lately. The degree of African indebtedness, the imperatives of loan repayment, and the long-term implications of ongoing political and economic changes, all make such a revision exigent indeed. Focusing on the Yoruba of southwestern Nigeria, this paper produces new evidence to reinterpret and redefine African precolonial financial institutions. The paper has two main parts. Part 1 focuses on the introduction of cowrie currency into Yorubaland and its impact on social stratification. Part 2 examines ajo, the savings institution, esusu, the rotating savings and credit associations (roscas), and …

The Role Of Size Exclusion Chromatography-Flame Atomic Absorption Spectrometry In The Treatment Chemistry Of Potable Water, Marina C. Koether

Faculty Articles

The percentage composition of Al₁₃, [AlO₄Al₁₂(OH)₂₄(H₂O)₁₂]⁷⁺, in water treatment coagulants is an important criterion in the development and use of polymeric coagulants. Polymeric coagulants are generally used in cold climates or with highly turbid waters. Size exclusion chromatography–flame atomic absorption spectrometry (SEC-FAAS) can separate Al₁₃ and monomeric Al within 6 min. The percentage composition of Al₁₃ and monomeric Al is determined by solving two simultaneous equations. Due to overlapping peaks, a 10% error is associated with this method of quantification. This method can be …

Cover And Contents

Turkish Journal of Veterinary & Animal Sciences

No abstract provided.

The Meeting Of Two Microbial Worlds: Geochemistry Of The Sulfate-Methane Interface, Walter S. Borowski, Charles K. Paull, William Ussler Iii

EKU Faculty and Staff Scholarship

No abstract provided.

Cover And Contents

Turkish Journal of Veterinary & Animal Sciences

No abstract provided.

Cover And Contents

Turkish Journal of Veterinary & Animal Sciences

No abstract provided.

Cover And Contents

Turkish Journal of Veterinary & Animal Sciences

No abstract provided.

Cover And Contents

Turkish Journal of Veterinary & Animal Sciences

No abstract provided.

The Tower Clock 2002, Tower Clock

Tower Clock Yearbooks

No abstract provided.

Java At Middle Age: Enabling Java For Computational Science, George K. Thiruvathukal

Computer Science: Faculty Publications and Other Works

Not long after the Mosaic Web browser appeared and Netscape communications formed, Sun Microsystems launched Java in a way that will be forever known as a marketing success story. All across the US, there were many Java Day events. I still have my t-shirts as proof of having been there.

The Classical Limit Of The Quantum Baker's Map, Mark Morgan-Tracy

Physics & Astronomy ETDs

This work concerns the finding of the semi-classical form of the coherent state representation for the class of quantum baker’s maps defined by Schack and Caves. It begins by introducing the finite-dimensional Hilbert space on which the quantum baker’s map is defined. Its pertinent features including the all important symmetry operators are introduced and given a full explanation. We also introduce the finite-dimensional phase space which will give the semi-classical limit a geometrical interpretation. For a D dimensional Hilbert space, the finite-dimensional phase space is found to be a grid with D2 points. Each point corresponds to a particular pair …

Fluorescence Studies In The Inductively Coupled Plasma, Anita Young

School of Geography, Earth and Environmental Sciences Theses

An Optima 3000 ICP-AES instrument was modified and the equipment necessary to carry out axial excitation atomic fluorescence was designed and constructed. Using this calibrated system, preliminary fluorescence experiments were not successful. As fluorescence is proportional to source intensity, it was considered that the excitation source, a hollow cathode lamp, may not have been sufficiently intense to produce fluorescence. A novel excitation source-driver system was designed and built in-house to operate HCLs, BDHCLs and LEDs with variable modulation frequencies and duty cycle capabilities. Studies investigating lamp response to changes in modulation frequency and duty cycle indicated that a lamp operated …

Barriers To Sustainability Among Tourism-Related Businesses : Identification And Reduction, Jonathan Andrew Vernon

School of Geography, Earth and Environmental Sciences Theses

The attainment of sustainable development has emerged as one of the main challenges facing society and the economy in the twenty-first century. In tourism, the English Tourism Council (2001 a, p. 11) recognise that sustainable tourism can no longer be regarded as an optional extra, but is fundamental to safeguarding the long-term competitiveness of the industry. To establish sustainable development as a primary strategic objective within the tourism industry represents a substantial challenge. Such a goal is problematic not least because the sector is so diverse and is based around a large number of small businesses which are not always …

Fundamental And Applied Measurements In Icp-Ms, Julian Robert Carter

School of Geography, Earth and Environmental Sciences Theses

Fundamental and applied aspects of ICP-MS have been investigated to gain an increased understanding of the technique and improve on its analytical capabilities. Dissociation temperatures of polyatomic ions were calculated using a double-focusing sector instrument, to obtain more reliable mass spectral data with controlled vapour introduction via a Dreschel bottle to allow accurate calculation of the ingredients in the plasma. The equilibrium temperature for the plasma, operated at 1280 W calculated using CO*, and as the thermometric probes, was c.a. 5800 - 7400 K, while using ArO* and ArC* as the thermometric probes the temperature calculated was c.a 2000 - …

A Method For The Perceptual Optimization Of Complex Visualizations, Donald H. House, Colin Ware

Center for Coastal and Ocean Mapping

A common problem in visualization applications is the display of one surface overlying another. Unfortunately, it is extremely difficult to do this clearly and effectively. Stereoscopic viewing can help, but in order for us to be able to see both surfaces simultaneously, they must be textured, and the top surface must be made partially transparent. There is also abundant evidence that all textures are not equal in helping to reveal surface shape, but there are no general guidelines describing the best set of textures to be used in this way. What makes the problem difficult to perceptually optimize is that …

Frame Of Reference Interaction., Matthew D. Plumlee, Colin Ware

Center for Coastal and Ocean Mapping

We present a unified set of 3D interaction techniques that demonstrates an alternative way of thinking about the navigation of large virtual spaces in non-immersive environments. Our alternative conceptual framework views navigation from a cognitive perspective—as a way of facilitating changes in user attention from one reference frame to another—rather than from the mechanical perspective of moving a camera between different points of interest. All of our techniques link multiple frames of reference in some meaningful way. Some techniques link multiple windows within a zooming environment while others allow seamless changes of user attention between static objects, moving objects, and …

Multibeam Volume Acoustic Backscatter Imagery And Reverberation Measurements In The Northeastern Gulf Of Mexico, Timoth C. Gallaudet, Christian De Moustier

Center for Coastal and Ocean Mapping

Multibeam volume acoustic backscatterimagery and reverberation measurements are derived from data collected in 200-m-deep waters in the northeastern Gulf of Mexico, with the Toroidal Volume Search Sonar (TVSS), a 68-kHz cylindrical sonar operated by the U.S. Navy’s Coastal System Station. The TVSS’s 360-degree vertical imaging plane allows simultaneous identification of multiple volume scattering sources and their discrimination from backscatter at the sea surface or the seafloor. This imaging capability is used to construct a three-dimensional representation of a pelagic fish school near the bottom. Scattering layers imaged in the mixed layer and upper thermocline are attributed to assemblages of epipelagic …

Ctap Evaluation Report: An Evaluation Of The Community Tourism Assessment Program , Thale Dillon

Institute for Tourism and Recreation Research Publications

This study evaluates the usefulness of the Community Tourism Assessment Process (CTAP) in Montana.

Quantitative Ground-Truthing Of Habitat Characteristics Using Video Mosaic Images, Randy G. Cutter Jr., Yuri Rzhanov, Larry A. Mayer

Center for Coastal and Ocean Mapping

No abstract provided.

Calculation Of The Stability Index In Parameter-Dependent Calculus Of Variations Problems: Buckling Of A Twisted Elastic Strut, Kathleen A. Hoffman, Robert S. Manning, Randy C. Paffenroth

Mathematics & Statistics Faculty Scholarship

No abstract provided.

Spaces Of Appearance: Writings On Contemporary Theatre And Performance, Antony David C. Williams

Other Faculty of Arts, Humanities and Business Theses

This thesis, a collection of previously published materials, reflects a plural and evolving engagement with theatre and performance over the past fifteen years or so: as researcher, writer, editor, teacher, practitioner, spectator. These have rarely been discreet categories for me, but rather different modalities of exploration and enquiry, interrelated spaces encouraging dynamic connectivities, flows and further questions. Section 1 offers critical accounts of the practices of four contemporary theatre directors: Jerzy Grotowski, Robert Wilson, Peter Brook and Ariane Mnouchkine. Section 2 draws on elements of contemporary philosophy and critical thinking to explore the mutable parameters of performance. lt proposes performative …