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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.
11

Reinforcement Learning in Keepaway Framework for RoboCup Simulation League

Li, Wei January 2011 (has links)
This thesis aims to apply the reinforcement learning into soccer robot and show the great power of reinforcement learning for the RoboCup. In the first part, the background of reinforcement learning is briefly introduced before showing the previous work on it. Therefore the difficulty in implementing reinforcement learning is proposed. The second section demonstrates basic concepts in reinforcement learning, including three fundamental elements, state, action and reward respectively, and three classical approaches, dynamic programming, monte carlo methods and temporal-difference learning respectively. When it comes to keepaway framework, more explanations are given to further combine keepaway with reinforcement learning. After the suggestion about sarsa algorithm with two function approximation, artificial neural network and tile coding, it is implemented successfully during the simulations. The results show it significantly improves the performance of soccer robot.
12

Modelling Tile Drains Under Present and Future Climate Conditions

O'Neill, Patrick 10 December 2008 (has links)
Modelling the impact of climate change on the water from agricultural areas on a regional scale over a 40 year time period is the subject of this thesis. The Grand River watershed spans approximately 290 km with an area of approximately 6,800 km². Approximately 90% of the watershed is agricultural land some of which is tile drained. These tile drains, which cover approximately 15% of the total land of the watershed, are installed to augment field drainage. The tile drains usually outlet somewhere along the perimeter of a property; the discharge then typically moves along the surface until it discharges into a surface water body such as a river, pond, or lake. Investigating the impact of climate change on agricultural tile drainage at a watershed scale can be achieved using modelling. The tile drains can affect both the water quality and the water quantity of a watershed. With the potential climatic changes, the storm intensity, and growing season also could change. Spatial data for the Grand River watershed was gathered to allow for further simulation. The data for tile drained areas was added to land use/land class and soil data for the watershed to produce a map of tile drained agricultural areas. Climate change scenarios were then simulated for each cell. Three climate change scenarios were investigated to determine the impact on tile drain discharge and the hydrological process for the watershed. The climate change scenarios that were chosen were the A2, A1B, and the B1 scenario of the Intergovernmental Panel on Climate Change. After the simulations were completed for the tiled areas and the results collected, the simulations showed the greatest impact of tile drain discharge in the spring season as well as the fall season. For the tiled cells the annual average discharge was approximately 0.22 m3/ha for 1999. The average discharge was approximately 0.15 m3/ha for April of 1999. April accounted for approximately 65% of the annual tile drainage for 1999. The climate change scenarios were simulated and the average annual discharge increased approximately 0.023 m3/ha and 0.021 m3/ha for the A2 and A1B scenarios respectively. The B1 scenario had an average annual decrease of approximately 0.022 m3/ha.
13

Performance Modeling for a 3D Graphics SoC

Lin, Ching-Yuan 07 September 2009 (has links)
The design of SoC is growing into more complicated, hence it is necessary to determine an efficient way to develop an SoC. If we can explore the relation between hardware architecture and software operation, there will be a great help for designing SoC platform. This paper builds the highly abstract simulation platform by using the development tool of SystemC and Coware for 3D graphics SoC. SystemC is entirely based on C++, so that Coware Inc. supports many TLM IP modules (like ARM CPU, ARM BUS, Memory, and etc.) for designer. For the purpose of fast building and modifying module by designer, this paper discusses 1. the behavior module performance in 3D Graphics Traditional Architecture, Tile-based Architecture of non-pipeline, pipeline, and GE&DMA Concurrence. 2. If it can use the software application to control procedure order of GE and RE, it would decrease the read/write times for RE reading from Tile. 3. To modify the read/write mechanism of Tile Buffer and change the returned values from memory, it would reduce the read/write times from memory. 4. And we need to observe FIFO sizes of traditional architecture to estimate affection performance.5. It uses Tile-Divider to predict the cutting triangle. Finally, 6. it modifies the AHB bus to AXI bus and divides single memory; therefore it can reduce the waiting bus time of GE and RE and improve the efficient of bus communication.
14

An Assessment of a Wetland-Reservoir Wastewater Treatment and Reuse System Receiving Agricultural Drainage Water in Nova Scotia

Haverstock, Michael James 13 September 2010 (has links)
A wastewater treatment and reuse system consisting of a tile drainage system, a constructed treatment wetland (CTW), a reservoir, and an irrigation system was established. The system supplied 780 mm of irrigation water for the 1.8 ha of drained land for the 2008 growing season. A hydraulic tracer study conducted in the CTW supported the use of a length to width ratio of 10:1. During 2008, annual nitrate-nitrogen (NO3--N) and Escherichia coli (E. coli) mass reductions were 67.6 and 63.3%, respectively. Elevated E. coli levels were observed in the reservoir during the warm season. Therefore, water may not be safe for irrigating crops consumed raw. The mean first-order areal uptake rate constants generated for NO3--N and E. coli were 8.0 and 6.4 m y-1, respectively, and are recommended for similar CTWs. A wetland area to drainage area ratio of 4.5% is recommended to achieve ? 70 % mass reduction of NO3--N and E. coli
15

Error-Resilient Tile Sets for DNA Self-Assembly

MENG, YA 25 August 2009 (has links)
Experiments have demonstrated that DNA molecules can compute like a machine to solve mathematical problems, which is significant because of their parallel computation ability. However, due to the nature of biochemical reactions, DNA computation suffers from errors, which are its main limitation. The abstract and kinetic Tile Assembly Models are now commonly used to simulate real DNA computing experiments, and to look for new methods to advance the accuracy of DNA-based computation. One means of controlling errors is through proofreading tile sets. Several such tile sets have been proposed in the literature, such as Chen and Goel’s snaked proofreading tile sets, the 2-way and 3-way overlay tile sets of Reif et al., and Rothemund and Cook’s n-way overlay tile sets. In the first part of this thesis, we analyze the performance of the Rothemund-Cook n-way overlay tile sets. We prove that the n-way overlay tile set contains n^2+3n+4 rule tiles. Simulation results show that these tile sets clearly perform better than tile sets without any error-control mechanism, and the performance improves as n increases. It is also proved that the error rates in assemblies formed by the 1-way and 2-way tile sets are O(epsilon^2), where epsilon is the error rate in assemblies without any error correction. In the second part of this thesis, we focus on a different error mechanism, namely,errors caused by imperfect or malformed tiles. We propose a model of malformed tiles, and consider the performance of various proofreading tile sets in the presence of malformed tiles. Our simulation results show that the Reif et al. 3-way overlay tile sets are able to best deal with malformed tiles. During the simulations, we observed that snaked proofreading tile sets always have trouble completing whole patterns when malformed tiles are present. We instead propose two modified snaked proofreading constructions, and verify through both simulations and analysis that the two modified constructions have much better performances. / Thesis (Master, Mathematics & Statistics) -- Queen's University, 2009-08-25 11:10:39.142
16

The Laconian-style roof : development, distribution, and technology /

Skoog, Victoria Nevius, January 1998 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1998. / Typescript. Vita. Includes bibliographical references (leaves [204]-214). Also available on the Internet.
17

The Laconian-style roof development, distribution, and technology /

Skoog, Victoria Nevius, January 1998 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1998. / Typescript. Vita. Includes bibliographical references (leaves [204]-214). Also available on the Internet.
18

Thermodynamics and Kinetics of DNA Tile-Based Self-Assembly

January 2016 (has links)
abstract: Deoxyribonucleic acid (DNA) has emerged as an attractive building material for creating complex architectures at the nanometer scale that simultaneously affords versatility and modularity. Particularly, the programmability of DNA enables the assembly of basic building units into increasingly complex, arbitrary shapes or patterns. With the expanding complexity and functionality of DNA toolboxes, a quantitative understanding of DNA self-assembly in terms of thermodynamics and kinetics, will provide researchers with more subtle design guidelines that facilitate more precise spatial and temporal control. This dissertation focuses on studying the physicochemical properties of DNA tile-based self-assembly process by recapitulating representative scenarios and intermediate states with unique assembly pathways. First, DNA double-helical tiles with increasing flexibility were designed to investigate the dimerization kinetics. The higher dimerization rates of more rigid tiles result from the opposing effects of higher activation energies and higher pre-exponential factors from the Arrhenius equation, where the pre-exponential factor dominates. Next, the thermodynamics and kinetics of single tile attachment to preformed “multitile” arrays were investigated to test the fundamental assumptions of tile assembly models. The results offer experimental evidences that double crossover tile attachment is determined by the electrostatic environment and the steric hindrance at the binding site. Finally, the assembly of double crossover tiles within a rhombic DNA origami frame was employed as the model system to investigate the competition between unseeded, facet and seeded nucleation. The results revealed that preference of nucleation types can be tuned by controlling the rate-limiting nucleation step. The works presented in this dissertation will be helpful for refining the DNA tile assembly model for future designs and simulations. Moreover, The works presented here could also be helpful in understanding how individual molecules interact and more complex cooperative bindings in chemistry and biology. The future direction will focus on the characterization of tile assembly at single molecule level and the development of error-free tile assembly systems. / Dissertation/Thesis / Doctoral Dissertation Chemistry 2016
19

The Effect of Control Tile Drainage on Soil Greenhouse Gas Emissions from Agricultural Fields in the South Nation Watershed of Ontario

Van Zandvoort, Alisha January 2016 (has links)
Controlled tile drainage (CTD) is an agricultural management practice with well-documented water quality and agronomic benefits, however, by virtue of its effect upon soil hydrology, CTD could potentially impact soil greenhouse gas (GHG: CO2, CH4, N2O) emissions. This study aimed to determine whether: (1) CTD affects soil GHG emissions throughout a dry (2012) and a wet (2013) growing season for corn, soybean, and forage fields in eastern Ontario, and (2) the location in a field with respect to a tile drain (over tile (OT) versus between tile (BT)) is important in GHG emissions. Non-steady state chambers were used for sampling soil GHG emissions in order to analyze GHG fluxes, the δ13C of soil-respired CO2 (RT), and for separating total soil respiration into its rhizosphere and soil components. There was no significant difference in average GHG emissions from CTD and UTD fields (except for 1/5 field pairs studied for N2O) and from OT and BT locations. The means of δ13C of RT were not statistically different (p>0.05) between 4/5 CTD and UTD field pairs, and between OT and BT locations in 4/5 CTD fields. The mean contributions from rhizosphere respiration and soil respiration did not differ (p>0.05) in 3/4 CTD and UTD field pairs. This lack of difference in GHG emissions is believed to have resulted from their being no difference in surface soil water contents among CTD and UTD fields and among OT and BT locations. It is believed that surface soil moisture did not vary because: (1) the water table was too low in 2012 for effective water table control, and (2) significant precipitation created equally wet surface soil in 2013. In 2013, the surface soil moisture was approximately 10% greater and this may be why there was an approximate 5 kg C/ha/day greater CO2 flux from soybean fields in 2013 than in 2012. δ13C was useful for distinguishing the source of CO2 emissions (rhizosphere versus soil respiration) in CTD fields when the crop and plant δ13C signatures varied. The results are useful for helping to capture the carbon footprint of tile drainage management practices imposed at field-scale.
20

Cross-section measurements of the Higgs boson decaying into a pair of tau leptons with the ATLAS detector / Cross-section measurements of the Higgs boson decaying into a pair of tau leptons with the ATLAS detector

Mlynáriková, Michaela January 2019 (has links)
The ATLAS experiment is one of the two general-purpose detectors at the Large Hadron Collider (LHC) at the European Organisation for Nuclear Research (CERN) in Switzerland. ATLAS is designed for precision mea- surements of particle properties, the search of the Higgs boson and new physics beyond the Standard Model. The experiment got worldwide atten- tion in 2012, when after the collaborative efforts with the CMS experiment the Higgs boson discovery was announced. After the discovery, the preci- sion measurements of its properties became one of the main objectives of the LHC physics programme, since a potential observation of deviations from the Standard Model predictions might lead to the discovery of new physics. In this thesis, the measurements of the Higgs boson production cross-sections in the H → ττ decay channel are presented. Based on the proton-proton collision data collected at the centre-of-mass energy of 13 TeV in years 2015 and 2016, the signal over the expected background from the other Standard Model processes is established with the observed significance of 4.4σ. Com- bined with the data collected at 7 and 8 TeV, the observed signal significance amounts to 6.4σ, which constitutes a single experiment observation of the H → ττ decays by ATLAS. All presented results are found to be consistent with...

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