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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.
1

An approach for estimating system engineering costs /

Tilton, Catherine J. January 1992 (has links)
Project report (M.S.)--Virginia Polytechnic Institute and State University. M.S. 1992. / Abstract. Includes bibliographical references (leaves 101-106). Also available via the Internet.
2

Ontologies as Bayesian Networks for Space Debris

Vasilieva, Stephania January 2016 (has links)
Space debris is a rising problem in today's world. Because there is so much in space that is unknown, it is critical to eventually catalog every piece. Since there are many attributes and properties attached to space objects, it is preferable to use an ontological classification method. The information presented in the ontology can then be used to answer questions about space debris. A Bayesian network would accomplish that because of its quantitative nature. The similarities between ontologies and Bayesian networks, such as their architectures and their flexibility, make it possible to integrate an ontology into a Bayesian network. Image determination and object collision assessment were used as applications to check the viability of integrating ontologies and Bayesian networks. It was determined that ontologies and Bayesian networks are tools that when combined can result in new useful quantitative information.
3

Examination of the technical and cultural effect of the evolving service contracting models on Government and Industry

La Bastille, Janine 09 1900 (has links)
Evaluation enable the Government to effectively and efficiently fulfill its mission. The current transition to Performance Based Service Acquisition (PBSA) and Multiple Award Contracts (MACs) have profound impact on program cubes, and many organizations are venturing concurrently into these strategies for the first time. The intent of PBSA is to maximize performance, innovation, and competition often at a savings." MACs are intended to benefit Government and industry by helping to ensure healthy competition and fair and reasonable contract prices. This thesis will examine the impact of PBSA and MAC contracting strategies on the Government program offices, along with the inherent cultural effects on both Government and industry.
4

Return on investment analysis of information warfare systems

Rios, Cesar G. 09 1900 (has links)
The United States Navy's Cryptologic Carry-On Program Office manages a portfolio of Information Warfare (IW) systems. This research and case study demonstrate how the Knowledge Value Added (KVA) Methodology can be used to formulate a framework for extracting and analyzing performance parameters and measures of effectiveness for each system. KVA measures the effectiveness and efficiency of CCOP systems and the impact they have on the Intelligence Collection Process (ICP) on board U.S. Navy Ships. By analyzing the outputs of the subprocesses involved in the ICP in common units of change, a price per unit of output can be generated to allocate both cost and revenue at the subprocess level. With this level of financial detail, a return on investment (ROI) analysis can be conducted for each process, or asset.
5

Effectiveness of Introductory Flight Screening (IFS) for United States Navy and Marine Corps student pilots

Morrison, Peter L. 09 1900 (has links)
This study examined the effectiveness of Introductory Flight Screening (IFS) for U.S. Navy and Marine Corps student pilots. It compared a non-IFS group to an IFS-complete group to determine if IFS had any effect on Primary drop-on-request (DOR) and flight-failure (FF) attrition. It then examined the return on investment (ROI) of the IFS program utilizing T-34 flying-hour costs, active-duty costs, and opportunity cost-savings of IFS-screened students who did not enter undergraduate pilot training. Results suggest that IFS did not have an effect on the DOR rate and may have produced the undesired effect of delaying the DOR-student's decision until later in the syllabus. IFS had a desirable effect on the FF attrition rate with no significant change in T-34 flight hours per FF. The combined Primary DOR and FF rate, although significantly lower, did not achieve expectations. The ROI analysis was completed with both composite-pay costs and Individual Account costs. In both cases, the IFS-investment costs significantly outweighed the IFS savings resulting in a net loss and an undesirable ROI. Several alternatives were discussed as possible improvements to the current IFS program.
6

Multi-beam digital antenna for radar, communications, and UAV tracking based on off-the-shelf wireless technologies

Gezer, Berat Levent 09 1900 (has links)
The state-of-art technologies keep generating new ways of improving on the performance of the old systems. Array antennas, one of the continuously improving technologies, brought many benefits to our life. The superiorities of array antennas remove the disadvantages of the old technology radars such as great sidelobes, vulnerability to the jammers, and degradation effect of the clutter. Array antennas find many applications on different areas. Today, unmanned aerial vehicles (UAVs) have begun to be seen in our life more often than before. UAVs prevent pilot loss of life. They carry out a variety of military and civilian missions such as surveillance and reconnaissance, target recognition, battle damage assessment, EW, search and rescue, and traffic monitoring. An important use of the UAVs is troop support, carrying out reconnaissance and surveillance missions, which requires maintaining a data-link with troops in order to send any data collected, such as video images, or audio. During operations it is necessary to continuously maintain a data and control link with the operator. This requires the ground station antenna to track the UAV so the antenna beam is pointed properly. The purpose of this research is to design and build an array to angle-track a UAV and, eventually, to accomplish the data transfer from the UAV to the ground station.
7

Influence of Turning on Military Vehicle Induced Rut Formation

Liu, Kun 01 December 2009 (has links)
Rut formation can severely influence soil conditions and vegetation, and reduce vehicle mobility. Vehicle operations can affect rut formation. Ruts formed in straight vehicle paths are different than when the vehicle turns. This research is mainly to investigate the effects of vehicle turning maneuvers on soil rut formation, including field tests, lab tests, and model development. Field tests were conducted at Yuma Training Center, Fort Riley and Fort Lewis on wheeled and tracked military vehicles. In field tests, rut depth, rut width and rut index were used as the main indicators to quantify a rut. A Vehicle Tracking System was mounted onto each vehicle to utilize the Global Positioning System. The vehicles were operated in spiral patterns to get constantly decreasing turning radius. The Vehicle Terrain Interaction terrain mechanics model was chosen to modify to predict rut formation during vehicle turning operations on yielding soils. In the modified VTI model, the resultant force on a single wheel is a dynamic variable correlated with the vehicle’s weight, velocity, and turning radius. In addition, lab tests were conduced on a tire and a track shoe in sand. Lateral forces and lateral displacements were applied under constant normal forces. The tire was pulled laterally and the track shoe was pulled back and forth to represent actual movement during vehicle turning. Results indicate that (1) rut depth, rut width and rut index increase with the decrease of TR, especially when TR is less than 20 meters; (2) vehicle parameters and soil parameters are statistically significant to affect rut formation; (3) the modified VTI model is able to predict rut formation when turning, with an improved R square of 0.43; (4) in lab tests, the final sinkage caused by the lateral force or displacement is 3 to 5 times the static sinkage; (5) rut depths increase from 65% to 548% of the initial rut depths under the effects of the combination of the multi-pass and turning maneuvers after multiple passes. This dissertation is a collection of five individual papers. More detailed description of test procedures and conclusions are found in these papers.
8

Incorporating fair share scheduling into the Layered Queueing Network model /

Li, Lianhua, January 1900 (has links)
Thesis (M.Sc.) - Carleton University, 2009. / Includes bibliographical references (p. 108-113). Also available in electronic format on the Internet.
9

A pulse method of formulating a mathematical model of a physical system

Tryon, William Ward 05 1900 (has links)
No description available.
10

The effects of system configuration on productivity and availability

Zimmerman, LeRoy 12 1900 (has links)
No description available.

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