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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.
81

A cost estimation model of the Sea Launch and Recovery Space Transportation System

Boone, Layne R. January 1990 (has links) (PDF)
Thesis (M.S. in Operations Research)--Naval Postgraduate School, September 1990. / Thesis Advisor(s): Melich, Michael ; Boger, Dan C. Second Reader: Rosenthal, Richard E. "September 1990." Description based on title screen viewed on December 16, 2009. DTIC Descriptor(s): Cost models, recovery, models, low costs, cost estimates, costs, sea launched, logistics, fuel tanks, space transportation, space missions, rocket fuels, position(location), fuels. DTIC Identifier(s): Launch vehicles, cost analysis, sea launch and recovery space transportation systems, theses. Author(s) subject terms: Optimization. Also available in print.
82

Estimating multimedia instruction performance based on workload characterization and measurement

Gheewala, Adil Adi. January 2002 (has links)
Thesis (M.S.)--University of Florida, 2002. / Title from title page of source document. Includes vita. Includes bibliographical references.
83

Optimization of a multi-axis electromechanical scanning system /

Urbina, Raul, January 2001 (has links)
Thesis (M.S.) in Mechanical Engineering--University of Maine, 2001. / Includes vita. Includes bibliographical references (leaves 54-55).
84

An introduction to certification and accreditation for new accreditors /

Stauffer, Natalie. January 2003 (has links) (PDF)
Thesis (M.S. in Computer Science)--Naval Postgraduate School, June 2003. / Thesis advisor(s): Karen Burke, Craig Rasmussen. Includes bibliographical references (p. 47-48). Also available online.
85

The removal of bacterial contamination using tunable charge distribution at the nanoscale

袁永怡, Yuen, Wing-yee, Jessica. January 2009 (has links)
published_or_final_version / Anatomy / Master / Master of Medical Sciences
86

Multi-terminal nano-electronic device simulations with atomistic details

Koo, Siu-kong, 顧兆光 January 2013 (has links)
Miniaturization of electronics is an unstoppable trend in the semiconductor industry. Moore’s Law has been the driving force to the advancement of the industry for half a century; and will continue to be the indicator for technology developments. As the feature size of an electronic device is reducing to the nano-scale level, quantum mechanics and atomistic details will become more and more important. In addition, simulations on devices with two or more terminals, such as transistors or junctions, are essential for design of electronics. Thus, Quantum mechanics based method with atomistic details for simulations of nano-electronic devices with two or more terminals is proposed and demonstrated. Similar studies can be found in the literature. However, most work was focusing on static / steady state problems, only few had looked into the dynamics. On the other hand, most methods being used in previous work can only handle two-terminal devices, while those few methods which can be applied for multi-terminal devices can only deal with steady state problems. Therefore, there is a research gap lies in multi-terminal time-dependent device simulations; and this gap will be filled by the work in this thesis. Quantum mechanics based method for open system has been used to simulate the electrical response through nano-electronic devices. Nearest neighbor tight binding models and carbon based models are the systems of interests. The core part of the structures of the systems of interest is a hexagonal ring. This is essentially a benzene ring based structure in our studies. Several situations for electrodes connecting the benzene ring at para- and metapositions are considered. Two-terminal cases and three-terminal cases for the mentioned systems have been studied. The third terminal in the three-terminal case is basically being viewed as a probe to the corresponding two-terminal case. For all the cases, steady state currents have been calculated; and currentvoltage curves of the systems have been obtained. Transient currents have also been calculated, so that dynamic responses of the systems are revealed. Different magnitudes of bias voltages have been applied to the systems. Linear response of the currents through the devices with respect to the bias voltage is observed for most cases. The para-position case can be taken as a reference to the meta-position case, due to simple structure and well-behaved responses. Interesting electric responses from the meta-position case is observed. The possibility for the meta-position system to be used as a transistor or other devices is briefly discussed. / published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy
87

Analysis and synthesis of positive systems under l₁ and L₁ performance

Chen, Xiaoming, 陈晓明 January 2014 (has links)
This thesis is concerned with the analysis and synthesis of positive systems under ℓ1 and L1 performance. Two classes of systems are considered: positive linear systems and positive Takagi-Sugeno (T-S) fuzzy systems. For positive linear systems, the controller, state-bounding observer and filter design problems are considered. Due to the special structures and unique features of positive systems, some previous approach used for general systems, such as similarity transformation, are no longer applicable to positive systems. First, the stabilization problem for positive linear systems is studied. In detail, analytical formulae to compute the exact values of ℓ1-induced and L1-induced norms are presented. Moreover, it is shown how the necessary and sufficient conditions can be constructed such that the closed-loop system is stable and satisfies a prescribed L1-induced performance. For single-input multiple-output (SIMO) positive systems, analytical solutions are established to show how the optimal ℓ1-induced and L1-induced controllers are designed. In addition, the L1-induced sparse state-feedback controller is investigated for continuous-time interval positive systems. Then, to estimate the state of positive systems at all times, the problem of positive state-bounding observers for interval positive systems is studied under the L1-induced performance. Necessary and sufficient conditions are presented to design a pair of state-bounding positive observers. Finally, the positive filtering problem is addressed for positive systems under the L1-induced performance. A pair of positive filters with error-bounding feature is designed to estimate the output of positive systems and the obtained results are expressed in terms of linear programming problems. For positive T-S fuzzy systems, the controller and filter design problems are investigated under the ℓ1-induced performance. First, novel performance characterization of positive fuzzy systems is established. Sufficient conditions are further established for the existence of state-feedback controller. An iterative convex optimization algorithm is developed to solve the design conditions. Furthermore, a pair of error-bounding positive filters are constructed to estimate the output of positive T-S fuzzy systems. A new performance characterization is first established to guarantee the asymptotic stability of the filtering error system with the ℓ1-induced performance. Then, sufficient conditions expressed by linear programming problems are derived to design the required filters. / published_or_final_version / Mechanical Engineering / Doctoral / Doctor of Philosophy
88

The analysis of nonlinear systems driven by almost periodic inputs

Van Zyl, Gideon Johannes 28 August 2008 (has links)
Not available / text
89

The acquisition of intellectual expertise: a computational and empirical theory

Kaczmarczyk, Elizabeth Christine 28 August 2008 (has links)
Not available / text
90

Garden Monitoring with Embedded Systems

von Hacht, Karl-Johan January 2015 (has links)
In today’s modern society the process of handling crops in an accountable way withoutloss have become more and more important. By letting a gardener evaluate the progressof his plants from relevant data one can reduce these losses and increase effectiveness ofthe whole plantation. This work is about the construction of such a system composedfrom a developers perspective of three different platforms, from the start of data samplingwithin the context of gardening to and end user easily able to understand the data thentranslated. The first platform will be created from scratch with both hardware andsoftware, the next assembled from already finished hardware components and build withsimpler software. The last will essentially only be a software solution in an alreadyfinished hardware environment.

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