411 |
Imaging of Cardiovascular Cellular Therapeutics with a Cryo-imaging SystemSteyer, Grant January 2010 (has links)
No description available.
|
412 |
IMAGING OF CARDIOVASCULAR CELLULAR THERAPEUTICS WITH A CRYO-IMAGING SYSTEMSteyer, Grant J. 17 May 2010 (has links)
No description available.
|
413 |
A comprehensive process for Automotive Model-Based ControlGurusubramanian, Sabarish 27 September 2013 (has links)
No description available.
|
414 |
Advanced Quantitative Measurement Methodology in Physics Education ResearchWang, Jing 11 September 2009 (has links)
No description available.
|
415 |
Design and Analysis of Model Based Nonlinear and Multi-Spectral Controllers with Focus on Motion Control of Continuous Smart StructuresKim, Byeongil 14 December 2010 (has links)
No description available.
|
416 |
Speech Segregation in Background Noise and Competing SpeechHu, Ke 17 July 2012 (has links)
No description available.
|
417 |
Motion Control of Under-actuated Aerial Robotic ManipulatorsJafarinasab, Mohammad January 2018 (has links)
This thesis presents model-based adaptive motion control algorithms for under-actuated
aerial robotic manipulators combining a conventional multi-rotor Unmanned Aerial Vehicle
(UAV) and a multi-link serial robotic arm. The resulting control problem is quite
challenging due to the complexity of the combined system dynamics, under-actuation, and
possible kinematic redundancy. The under-actuation imposes second-order nonholonomic
constraints on the system motion and prevents independent control of all system degrees
of freedom (DOFs). Desired reference trajectories can only be provided for a selected
group of independent DOFs, whereas the references for the remaining DOFs must be determined such that they are consistent with the motion constraints. This restriction prevents
the application of common model-based control methods to the problem of this thesis. Using
insights from the system under-actuated dynamics, four motion control strategies are
proposed which allow for semi-autonomous and fully-autonomous operation. The control
algorithm is fully developed and presented for two of these strategies; its development for
the other two configurations follows similar steps and hence is omitted from the thesis.
The proposed controllers incorporate the combined dynamics of the UAV base and the serial
arm, and properly account for the two degrees of under-actuation in the plane of the
propellers. The algorithms develop and employ the second-order nonholonomic constraints
to numerically determine motion references for the dependent DOFs which are consistent with the motion constraints. This is a unique feature of the motion control algorithms
in this thesis which sets them apart from all other prior work in the literature of UAVmanipulators.
The control developments follow the so-called method of virtual decomposition,
which by employing a Newtonian formulation of the UAV-Manipulator dynamics,
sidesteps the complexities associated with the derivation and parametrization of a lumped
Lagrangian dynamics model. The algorithms are guaranteed to produce feasible control
commands as the constraints associated with the under-actuation are explicitly considered
in the control calculations. A method is proposed to handle possible kinematic redundancy
in the presence of second-order motion constraints. The control design is also extended to
include the propeller dynamics, for cases that such dynamics may significantly impact the
system response. A Lyapunov analysis demonstrates the stability of the overall system and
the convergence of the motion tracking errors. Experimental results with an octo-copter integrated with a 3 DOF robotic manipulator show the effectiveness of the proposed control strategies. / Thesis / Doctor of Philosophy (PhD)
|
418 |
Model-based Tests for Standards Evaluation and Biological AssessmentsLi, Zhengrong 27 September 2007 (has links)
Implementation of the Clean Water Act requires agencies to monitor aquatic sites on a regular basis and evaluate the quality of these sites. Sites are evaluated individually even though there may be numerous sites within a watershed. In some cases, sampling frequency is inadequate and the evaluation of site quality may have low reliability.
This dissertation evaluates testing procedures for determination of site quality based on modelbased procedures that allow for other sites to contribute information to the data from the test site. Test procedures are described for situations that involve multiple measurements from sites within a region and single measurements when stressor information is available or when covariates are used to account for individual site differences.
Tests based on analysis of variance methods are described for fixed effects and random effects models. The proposed model-based tests compare limits (tolerance limits or prediction limits) for the data with the known standard. When the sample size for the test site is small, using model-based tests improves the detection of impaired sites. The effects of sample size, heterogeneity of variance, and similarity between sites are discussed. Reference-based standards and corresponding evaluation of site quality are also considered. Regression-based tests provide methods for incorporating information from other sites when there is information on stressors or covariates.
Extension of some of the methods to multivariate biological observations and stressors is also discussed. Redundancy analysis is used as a graphical method for describing the relationship between biological metrics and stressors. A clustering method for finding stressor-response relationships is presented and illustrated using data from the Mid-Atlantic Highlands. Multivariate elliptical and univariate regions for assessment of site quality are discussed. / Ph. D.
|
419 |
Model and Control System Development for a Plug-In Parallel Hybrid Electric VehicleMarquez Brunal, Eduardo De Jesus 20 June 2016 (has links)
The Hybrid Electric Vehicle Team (HEVT) of Virginia Tech is participating in the EcoCAR 3 Advanced Vehicle Technology Competition series organized by Argonne National Labs (ANL), and sponsored by General Motors (GM) and the U.S. Department of Energy (DOE). EcoCAR 3 is a 4-year collegiate competition that challenges student with redesigning a 2016 Chevrolet Camaro into a hybrid. The five main goals of EcoCAR 3 are to reduce petroleum energy use (PEU) and green house gas (GHG) emissions while maintaining safety, consumer acceptability, and performance, with an increased focus on cost and innovation. HEVT selected a P3 Plug-in Parallel hybrid electric vehicle (PHEV) to meet design goals and competition requirements. This study presents different stages of the vehicle development process (VDP) followed to integrate the HEVT Camaro. This work documents the control system development process up to Year 2 of EcoCAR 3.
The modeling process to select a powertrain is the first stage in this research. Several viable powertrains and the respective vehicle technical specifications (VTS) are evaluated. The P3 parallel configuration with a V8 engine is chosen because it generated the set of VTS that best meet design goals and EcoCAR 3 requirements. The V8 engine also preserves the heritage of the Camaro, which is attractive to the established target market. In addition, E85 is chosen as the fuel for the powertrain because of the increased impact it has on GHG emissions compared to E10 and gasoline. The use of advanced methods and techniques like model based design (MBD), and rapid control prototyping (RCP) allow for faster development of engineering products in industry. Using advanced engineering techniques has a tremendous educational value, and these techniques can assist the development of a functional and safe hybrid control system. HEVT has developed models of the selected hybrid powertrain to test the control code developed in software. The strategy developed is a Fuzzy controller for torque management in charge depleting (CD) and charge sustaining (CS) modes. The developed strategy proves to be functional without having a negative impact of the energy consumption characteristics of the hybrid powertrain. Bench testing activities with the V8 engine, a low voltage (LV) motor, and high voltage (HV) battery facilitated learning about communication, safety, and functionality requirements for the three components. Finally, the process for parallel development of models and control code is presented as a way to implement more effective team dynamics. / Master of Science
|
420 |
Rapid Prototyping of Software Defined Radios using Model Based Design for FPGAsMoola , Sabares S. 08 September 2010 (has links)
With the rapid migration of physical layer design of radio towards software, it becomes necessary to select or develop the platform and tools that help in achieving rapid design and development along with flexibility and reconfigurability. The availability of field programmable gate arrays (FPGAs) has promoted the concept of reconfigurable hardware for software defined radio (SDR). It enables the designer to create high speed radios with flexibility, low latency and high throughput. Generally, the traditional method of designing FPGA based radios limits productivity. Productivity can be improved using Model based design (MBD) tools. These tools encourage a modular way of developing waveforms for radios. The tools based on MBD have been the focus of recent research exploring the concept of the platform independent model (PIM) and portability across platforms by the platform specific model (PSM). The thesis presented here explores the tools based on MBD to achieve prototyping for wireless standards like IEEE 802.11a and IEEE 802.16e on reconfigurable hardware. It also describes the interfacing of the universal software radio peripheral (USRP2), acting as a radio frequency (RF) front end, with an additional FPGA board for baseband processing. / Master of Science
|
Page generated in 0.0615 seconds