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:"Texas A&M University" +contributor:("Morgan, Joseph"). Showing records 1 – 3 of 3 total matches.

Search Limiters

Last 2 Years | English Only

No search limiters apply to these results.

▼ Search Limiters


Texas A&M University

1. Malawey, David Paul. Mechanical Design and Optimization of a Standardized Cubesat.

Degree: MS, Mechanical Engineering, 2016, Texas A&M University

Cubesats are tiny space exploration vessels with a lower cost than most satellites in history. Rapidly, studies are taking place on this technology to the degree that published papers on cubesats seem to have doubled between the initial background study and thesis completion. These satellites have a multitude of purposes and missions but all conform to one small physical form factor. The research presented here aims to create a cubesat mechanical design that is flexible enough to accommodate varying payloads and is fed by a multidisciplinary design optimizer in order to make best use of the limited volume of the craft. The study consists of the development of a simplified math model of the satellite and subsystems, 3D model with FEA analyses based on successful past designs, and the creation of a real prototype using a CNC mill along with measures taken to reduce time and cost of prototyping. The results of the optimization suggest that a cubesat is a valid candidate for an optimizer which uses both heuristic and gradient based algorithms. The optimizer first finds the satellite design with the lowest mass to meet the mission criteria while satisfying constraints on propulsion, electrical power, and structure strength. The design is a product of six variables (propellant, thruster valve, structure material, solar panel quantity, battery quantity, and structure thickness). Following the problem of mass minimization, cost is introduced in a dual objective optimization and a Pareto front of design options is generated. Prototype development resulted in major improvements to prototyping speed and cost for the conditions at hand. The methodology and assumptions shown enhance the argument that these conditions are conservative with respect to most cubesat design requirements including strength, and manufacturing cost, and other metrics. Both the optimizer and the modular prototype of the spacecraft maintains an ability to manipulate the design in future iterations to offer an effective standardized platform. Throughout this thesis, key lessons are shared and weaknesses and uncertainties are identified. Finally, future work is offered on this research topic which would enhance the effectiveness and certainty for success in full cubesat design implementation. Advisors/Committee Members: Langari, Reza (advisor), Morgan, Joseph (advisor), Allaire, Douglas (committee member).

Subjects/Keywords: optimization; cubesat

Record DetailsSimilar RecordsGoogle PlusoneFacebookTwitterCiteULikeMendeleyreddit

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

APA (6th Edition):

Malawey, D. P. (2016). Mechanical Design and Optimization of a Standardized Cubesat. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/174238

Chicago Manual of Style (16th Edition):

Malawey, David Paul. “Mechanical Design and Optimization of a Standardized Cubesat.” 2016. Masters Thesis, Texas A&M University. Accessed September 29, 2020. http://hdl.handle.net/1969.1/174238.

MLA Handbook (7th Edition):

Malawey, David Paul. “Mechanical Design and Optimization of a Standardized Cubesat.” 2016. Web. 29 Sep 2020.

Vancouver:

Malawey DP. Mechanical Design and Optimization of a Standardized Cubesat. [Internet] [Masters thesis]. Texas A&M University; 2016. [cited 2020 Sep 29]. Available from: http://hdl.handle.net/1969.1/174238.

Council of Science Editors:

Malawey DP. Mechanical Design and Optimization of a Standardized Cubesat. [Masters Thesis]. Texas A&M University; 2016. Available from: http://hdl.handle.net/1969.1/174238

2. Reyna, Baraquiel. Medical Hardware for the Space Environment: An Engineering Experience at the National Aeronautics and Space Administration.

Degree: Doctor of Engineering, Engineering, 2011, Texas A&M University

The complexity and amount of medical hardware needed by National Aeronautics and Space Administration (NASA) constantly shifts with mission requirements. Early missions such as Mercury, Gemini, and Apollo required minimal, relatively non-complex medical hardware, but as mission lengths have increased from hours to multiple months and mission crew sizes have increased from one to seven, so has the amount and complexity of medical hardware. As such, a need has arisen to develop a methodology by which medical hardware is certified for the space environment in a safe, consistent, and economically viable manner. This record of study documents my experiences certifying medical hardware for the space environment by providing two specific certification examples, a defibrillator, and automated external defibrillator and provides a brief history of the medical hardware used by NASA for its manned space programs. Advisors/Committee Members: Lessard, Charles (advisor), Hyman, William A. (committee member), Johnson-Throop, Kathy (committee member), Morgan, Joseph A. (committee member), Porter, Jay R. (committee member).

Subjects/Keywords: Medical Hardware; National Aeronautics and Space Administration; NASA

Record DetailsSimilar RecordsGoogle PlusoneFacebookTwitterCiteULikeMendeleyreddit

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

APA (6th Edition):

Reyna, B. (2011). Medical Hardware for the Space Environment: An Engineering Experience at the National Aeronautics and Space Administration. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2011-08-10077

Chicago Manual of Style (16th Edition):

Reyna, Baraquiel. “Medical Hardware for the Space Environment: An Engineering Experience at the National Aeronautics and Space Administration.” 2011. Doctoral Dissertation, Texas A&M University. Accessed September 29, 2020. http://hdl.handle.net/1969.1/ETD-TAMU-2011-08-10077.

MLA Handbook (7th Edition):

Reyna, Baraquiel. “Medical Hardware for the Space Environment: An Engineering Experience at the National Aeronautics and Space Administration.” 2011. Web. 29 Sep 2020.

Vancouver:

Reyna B. Medical Hardware for the Space Environment: An Engineering Experience at the National Aeronautics and Space Administration. [Internet] [Doctoral dissertation]. Texas A&M University; 2011. [cited 2020 Sep 29]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2011-08-10077.

Council of Science Editors:

Reyna B. Medical Hardware for the Space Environment: An Engineering Experience at the National Aeronautics and Space Administration. [Doctoral Dissertation]. Texas A&M University; 2011. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2011-08-10077


Texas A&M University

3. Walden, Troy Duane. The Drug Evaluation and Classification Program in the state of Texas: a validation study.

Degree: PhD, Educational Human Resource Development, 2005, Texas A&M University

A retrospective research study was conducted to determine the effectiveness of the Drug Evaluation and Classification Program (DECP) procedures in order to identify subjects under the influence of specific drug categories. The investigator wanted to determine if the procedures are reliable and whether a drug recognition expert (DRE) can properly apply the DECP procedures to consistently identify the drug category and have that opinion supported by toxicology. A total of 324 enforcement drug influence evaluations (DIEs) were obtained from the DRE data tracking system (DRE-DTS) that is maintained through the National Highway Traffic Safety Administration (NHTSA). Toxicology results related to each DIE were compared to the DRE??s drug category prediction. The objectives of the study were to determine if the 12-step DECP process enables DREs to identify drug categories and those most frequently identified and confirmed in Texas. Using the DECP, the DRE??s ability to identify specific drugs according to categories and to have the identification supported by toxicology was moderately accurate at best. Of the 324 evaluations that had toxicology results, the DRE correctly identified drug categories as follows: depressants, 60.5%; stimulants, 32%; hallucinogens, 12%; PCP, 46.6%; narcotic analgesics, 51.6%; inhalants, 14.2%; and cannabis, 64.9%. To determine which drug categories were called most frequently, the enforcement DIEs were analyzed according to each specific category. The investigator found the following drug categories were most frequently called by DREs who evaluated subjects: depressants, 182; cannabis, 142; narcotic analgesics, 83; stimulants, 62; PCP, 18; inhalants, 4; and hallucinogens, 1. To determine which drug categories were most frequently confirmed through toxicology, the enforcement DIEs were analyzed for the number of confirmations for each specific drug category. The investigator found the following drug categories were most frequently confirmed through toxicology: depressants, 176; cannabis, 140; stimulants, 106; narcotic analgesics, 99; PCP, 26; hallucinogens, 8; and inhalants, 4. The investigator was able to determine, based on the DRE-DTS data, that Texas DREs are only moderately accurate in identifying drug categories when utilizing the DECP procedures in enforcement settings. Furthermore, the DRE??s prediction of drug category was not consistently supported by toxicology results obtained from evaluated subjects. Advisors/Committee Members: Lynham, Susan A. (advisor), Stenning, Walter F. (advisor), Morgan, Joseph (committee member), Paprock, Kenneth (committee member).

Subjects/Keywords: Drug Recognition Expert; Drug Evaluation and Classification Program; Sobriety Testing

Record DetailsSimilar RecordsGoogle PlusoneFacebookTwitterCiteULikeMendeleyreddit

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

APA (6th Edition):

Walden, T. D. (2005). The Drug Evaluation and Classification Program in the state of Texas: a validation study. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/2327

Chicago Manual of Style (16th Edition):

Walden, Troy Duane. “The Drug Evaluation and Classification Program in the state of Texas: a validation study.” 2005. Doctoral Dissertation, Texas A&M University. Accessed September 29, 2020. http://hdl.handle.net/1969.1/2327.

MLA Handbook (7th Edition):

Walden, Troy Duane. “The Drug Evaluation and Classification Program in the state of Texas: a validation study.” 2005. Web. 29 Sep 2020.

Vancouver:

Walden TD. The Drug Evaluation and Classification Program in the state of Texas: a validation study. [Internet] [Doctoral dissertation]. Texas A&M University; 2005. [cited 2020 Sep 29]. Available from: http://hdl.handle.net/1969.1/2327.

Council of Science Editors:

Walden TD. The Drug Evaluation and Classification Program in the state of Texas: a validation study. [Doctoral Dissertation]. Texas A&M University; 2005. Available from: http://hdl.handle.net/1969.1/2327

.