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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
931

Physics-based modelling and measurement of advanced manufacturing machinery’s positioning accuracy : Machine tools, industrial manipulators and their positioning accuracy

Theissen, Nikolas Alexander January 2019 (has links)
Advanced manufacturing machinery is a corner stone of essential industries of technologicallydeveloped societies. Their accuracy permits the production of complexproducts according to tight geometric dimensions and tolerances for high efficiency,interchangeability and sustainability. The accuracy of advanced manufacturingmachinery can be quantified by the performance measure of positioning accuracy.Positioning accuracy measures the closeness between a commanded and an attainedposition on a machine tool or industrial manipulator, and it is ruled by lawsof physics in classical mechanics and thermodynamics. These laws can be applied tomodel how much the machinery deflects due to gravity, expands due to a change intemperature and how much and how long it vibrates due to process forces; hence,one can quantify how much the accuracy decreases. Thus, to produce machinerywith ever higher accuracy and precision one can design machines which deflect,expand and vibrate less or one can understand and model the actual behaviour ofthe machinery to compensate for it.This licentiate thesis uses physics-based modelling to quantify the positioningaccuracy of machine tools and industrial robots. The work investigates the potentialincrease in positioning accuracy because of the simultaneous modelling of the kinematics,static deflections, vibrations and thermo-elasticity as a lumped-parametermodel of the machinery. Consequently the models can be used to quantify thechange of the accuracy throughout the workspace.The lumped parameter models presented in this work require empirical modelcalibration and validation. The success of both, calibration and validation, dependson the availability of the right measurement instruments, as these need to be ableto capture the actual positioning accuracy of machinery. This thesis focuses on theimportance of measurement instruments in industry and metrology and creates acatalogue of requirements and trends to identify the features of the measurementinstruments required for the factories of the future. These novel measurement instrumentsshall be able to improve model calibration and validation for an improvedoverall equipment effectiveness, improved product quality, reduced costs, improvedsafety and sustainability as a result of physics-based modelling and measurementof advanced manufacturing machinery.
932

A History of the Oboe from Antiquity to 1750

Stephens, Perry O. 08 1900 (has links)
The purpose of this study is to trace the development of the oboe and its use from the primitive double reed instruments to the oboes of the Baroque Period. Toward the end of this period the oboe became thoroughly established as an important section in the symphony orchestra and has remained so to the present time.
933

Attentional demand evaluation for an automobile moving-map navigation system

Dingus, Thomas A. January 1987 (has links)
A study was undertaken to test and evaluate the human factors design aspects of an automobile moving-map navigation system. The primary objective of the study was to assess the driver attentional demand required by the navigation system during vehicle operation. A secondary objective of the study was to assess design specifics and determine whether or not the design was optimal in terms of efficiency of use in an automotive environment. Thirty-two driver-subjects drove a specially instrumented 1985 Cadillac Sedan de Ville on public roadways for this research. A cross-section of driver-subjects (both genders, ages 18 to 73, and driving experience from 2,000 to 40,000 miles per year) participated, and a cross·section of roadway types (residential, two-lane state route, and limited·access four-lane) and traffic conditions (light and moderate) were used as part of this research. The driver-subjects were asked to perform a variety of tasks while operating the research vehicle. These tasks included navigation tasks normally performed while using the navigation system, as well as a wide variety of conventional automotive tasks (e.g., tuning the radio or reading the speedometer) normally performed during vehicle operation. The purpose of asking the driver-subjects to perform a variety of conventional automotive tasks was so that direct comparisons in attentional demand could be made between tasks performed daily in an automotive environment and the navigation tasks. Twenty-one performance and behavioral measures were collected and analyzed for this research. These measures included eye—scanning and dwell-time measures, task-completion-time measures, and a variety of measures indicating driver performance and behavior. The data analyses for these measures focused on two major goals. First, the analyses determined which tasks (both navigator and conventional) required the highest attentional demand. Second, the analyses were used to determine groups of tasks which, for all practical purposes, required equivalent attentional demand. The results of the analyses indicated that the navigation system is a relatively effective device, useful for its intended purpose. The results also indicated that a number of design improvements are required, however, to optimize the safety and efficiency of the device. An iterative process of design improvement and further research into the effects of improved design on required attentional demand is therefore recommended. / Ph. D.
934

Keyboardistens roll i en ensemble : En undersökning om olika keyboardinstrument i relation till grooveoch timing

Åberg, Isak January 2023 (has links)
This thesis is an examination about different keyboard instruments and how the pianist can use them in a groove context. All keyboard instruments have different attack, decay, release, overtones, and dynamics, as well as different opportunities to affect these parameters. Every instrument also involves various opportunities and challenges in an ensemble, in the way they affect and are affected by the playing of the fellow musicians. The examination involved that I played, recorded, and transcribed different keyboard patterns from different recordings. I played every pattern with four different instruments and explored how the groove changed based on the instruments I played and how I could use the parameters of every instrument to get variation. First, I did this playing to drum loops and later with real musicians.   My conclusions are that getting an overview of the overtones and how distinct the instruments can be is the key to improve your ability to play different keyboard instruments. To get to know instruments and their ways to express intensity is the essence of finding your way into the groove.
935

Perspectives on improvisation in beginning string pedagogy: A description of teacher anxiety, confidence, and attitude

Smith, Kimberly A. 26 April 2010 (has links)
No description available.
936

The Development of Civil War Brass Band Instruments into Modern-Day Brass Band Instruments with a Related Teaching Unit For a High School General Music Course

Lewis, Joseph M., Jr. 29 July 2015 (has links)
No description available.
937

“The Miracle of Unintelligibility”: The Music and Invented Instruments of Lucia Dlugoszewski

Lewis, Kevin D. January 2011 (has links)
No description available.
938

A parametric evaluation of vehicle crash performance

Kumblekere, Jaikanth B. January 1996 (has links)
No description available.
939

The effects of structured singing activities and self-evaluation practice on elementary band students' instrumental music performance, melodic tonal imagery, self-evaluation, and attitude /

Davis, LaPointe Manuel January 1981 (has links)
No description available.
940

The measurement of finger dexterity in woodwind and brass instrumentalists : a developmental study /

Callahan, Gary L. January 1986 (has links)
No description available.

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