Advanced search options

Advanced Search Options 🞨

Browse by author name (“Author name starts with…”).

Find ETDs with:

in
/  
in
/  
in
/  
in

Written in Published in Earliest date Latest date

Sorted by

Results per page:

Sorted by: relevance · author · university · dateNew search

You searched for +publisher:"University of Alabama" +contributor:("Shepard, William S."). Showing records 1 – 3 of 3 total matches.

Search Limiters

Last 2 Years | English Only

No search limiters apply to these results.

▼ Search Limiters


University of Alabama

1. Kavanaugh, Joshua Stephen. Dynamics of vacuum-sealed, double-leaf partitions.

Degree: 2015, University of Alabama

The goal of this research is to investigate the feasibility and potential effectiveness of using vacuum-sealed, double-leaf partitions for applications in noise control. Substantial work has been done previously on double-leaf partitions where the acoustics of the inner chamber and mechanical vibrations of structural supports are passively and actively controlled. The work presented here is unique in that the proposed system aims to eliminate the need for active acoustic control of transmitted acoustic energy by removing all the air between the two panels of the double partition. Therefore, the only remaining energy paths would be along the boundary and at the points where there are intermediate structural supports connecting the two panels. The eventual goal of the research is to develop a high-loss double-leaf partition that simplifies active control by removing the need for control of the air cavity and channeling all the energy into discrete structural paths. The work presented here is a first step towards the goal of designing a high-loss, actively-controlled double-leaf partition with an air-evacuated inner chamber. One experiment is conducted to investigate the effects of various levels of vacuum on the response of a double-leaf partition whose panels are mechanically coupled only at the boundary. Another experiment is conducted which investigates the effect of changing the stiffness of an intermediate support coupling the two panels of a double-leaf partition in which a vacuum has been applied to the inner cavity. The available equipment was able to maintain a 99% vacuum between the panels. Both experiments are accompanied by analytical models used to investigate the importance of various dynamic parameters. Results show that the vacuum-sealed system shows some potential for increased transmission loss, primarily by the changing the natural frequencies of the double-leaf partition. (Published By University of Alabama Libraries) Advisors/Committee Members: Shepard, William S., Mahmoodi, Seyed N., Hubner, James P., University of Alabama. Dept. of Mechanical Engineering.

Subjects/Keywords: Electronic Thesis or Dissertation;  – thesis; Mechanical engineering; Acoustics; Virology; acoustics; double-leaf partition; noise control; passive control; vacuum

Record DetailsSimilar RecordsGoogle PlusoneFacebookTwitterCiteULikeMendeleyreddit

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Kavanaugh, J. S. (2015). Dynamics of vacuum-sealed, double-leaf partitions. (Thesis). University of Alabama. Retrieved from http://purl.lib.ua.edu/131945

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Kavanaugh, Joshua Stephen. “Dynamics of vacuum-sealed, double-leaf partitions.” 2015. Thesis, University of Alabama. Accessed August 13, 2020. http://purl.lib.ua.edu/131945.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Kavanaugh, Joshua Stephen. “Dynamics of vacuum-sealed, double-leaf partitions.” 2015. Web. 13 Aug 2020.

Vancouver:

Kavanaugh JS. Dynamics of vacuum-sealed, double-leaf partitions. [Internet] [Thesis]. University of Alabama; 2015. [cited 2020 Aug 13]. Available from: http://purl.lib.ua.edu/131945.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Kavanaugh JS. Dynamics of vacuum-sealed, double-leaf partitions. [Thesis]. University of Alabama; 2015. Available from: http://purl.lib.ua.edu/131945

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation


University of Alabama

2. Roget, Adam Brent. Study of vibration and audible noise generated by shunt capacitor banks at substations serving non-linear loads.

Degree: 2011, University of Alabama

At the request of a local utility provider, a study was conducted to determine why capacitor banks located at two substations supplying power to a steel mill are creating audible noise. A method to decrease the amount of audible noise was also requested. The construction of the banks and the possible cause of excitation are discussed. Electrical current and acoustic harmonic measurements taken at each substation are presented. Vibration testing of the banks was conducted to determine the mechanical natural frequencies, and the results are given. Possible solutions to reduce the amount of audible noise from the capacitors conclude the discussion. (Published By University of Alabama Libraries) Advisors/Committee Members: Haskew, Timothy A., Li, Shuhui, Shepard, William S., Woodbury, Keith A., University of Alabama. Dept. of Electrical and Computer Engineering.

Subjects/Keywords: Electronic Thesis or Dissertation;  – thesis; Electrical engineering; Acoustics; Mechanical engineering; Acoustics; Capacitor; Vibration

Record DetailsSimilar RecordsGoogle PlusoneFacebookTwitterCiteULikeMendeleyreddit

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Roget, A. B. (2011). Study of vibration and audible noise generated by shunt capacitor banks at substations serving non-linear loads. (Thesis). University of Alabama. Retrieved from http://purl.lib.ua.edu/41261

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Roget, Adam Brent. “Study of vibration and audible noise generated by shunt capacitor banks at substations serving non-linear loads.” 2011. Thesis, University of Alabama. Accessed August 13, 2020. http://purl.lib.ua.edu/41261.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Roget, Adam Brent. “Study of vibration and audible noise generated by shunt capacitor banks at substations serving non-linear loads.” 2011. Web. 13 Aug 2020.

Vancouver:

Roget AB. Study of vibration and audible noise generated by shunt capacitor banks at substations serving non-linear loads. [Internet] [Thesis]. University of Alabama; 2011. [cited 2020 Aug 13]. Available from: http://purl.lib.ua.edu/41261.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Roget AB. Study of vibration and audible noise generated by shunt capacitor banks at substations serving non-linear loads. [Thesis]. University of Alabama; 2011. Available from: http://purl.lib.ua.edu/41261

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation


University of Alabama

3. Taylor, William Matthew. Evaluation of microstructure response under various loading and boundary conditions to aid in the establishment of a threshold criterion for mild traumatic brain injury.

Degree: 2011, University of Alabama

In previous research studies, the geometric and elastic properties for a critical component of axon health, the microtubule (MT), have been determined using lateral indentation with the tip of an atomic force microscope (AFM). Although the response due to the indentations caused by the AFM was observed to be linear for most of the tests, forces greater than 300pN would result in a permanent irreversible collapse of the MT's structure. While the intent of those researchers was not to evaluate microtubule strength properties, that load can be used as a starting point to evaluate internal stress failure criterion for such structures. To that end, the current research is investigating MT strength by replicating the loading and boundary conditions in a finite element model. This work is an extension of previous work aimed at using this 300 pN point load to develop failure criteria for MTs under more realistic loading conditions. In the present work, modeling has been used to correlate the AFM point load response with the more realistic distributed loading conditions that would result during a brain injury event. Furthermore, the impact of nearby MTs on the stresses that occur under similar loading conditions has also examined. Correspondingly, models that include dynamic wave propagation through the microtubule were also studied. These results were used to analytically examine different loading conditions in order to equate various scenarios so that the determination of a stress threshold related to MT structural failure could more easily be examined in later work. The failure criterion determined in both cases would aid in evaluating brain injury studies that involve pressure wave propagation in whole-head finite element models, even when such models represent the white matter using homogeneous properties. (Published By University of Alabama Libraries) Advisors/Committee Members: Shepard, William S., Todd, Beth A., Williams, Keith A., Barkey, Mark E., University of Alabama. Dept. of Mechanical Engineering.

Subjects/Keywords: Electronic Thesis or Dissertation;  – thesis; Nanoscience; Mechanical engineering

Record DetailsSimilar RecordsGoogle PlusoneFacebookTwitterCiteULikeMendeleyreddit

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Taylor, W. M. (2011). Evaluation of microstructure response under various loading and boundary conditions to aid in the establishment of a threshold criterion for mild traumatic brain injury. (Thesis). University of Alabama. Retrieved from http://purl.lib.ua.edu/54192

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Taylor, William Matthew. “Evaluation of microstructure response under various loading and boundary conditions to aid in the establishment of a threshold criterion for mild traumatic brain injury.” 2011. Thesis, University of Alabama. Accessed August 13, 2020. http://purl.lib.ua.edu/54192.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Taylor, William Matthew. “Evaluation of microstructure response under various loading and boundary conditions to aid in the establishment of a threshold criterion for mild traumatic brain injury.” 2011. Web. 13 Aug 2020.

Vancouver:

Taylor WM. Evaluation of microstructure response under various loading and boundary conditions to aid in the establishment of a threshold criterion for mild traumatic brain injury. [Internet] [Thesis]. University of Alabama; 2011. [cited 2020 Aug 13]. Available from: http://purl.lib.ua.edu/54192.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Taylor WM. Evaluation of microstructure response under various loading and boundary conditions to aid in the establishment of a threshold criterion for mild traumatic brain injury. [Thesis]. University of Alabama; 2011. Available from: http://purl.lib.ua.edu/54192

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

.