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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.
251

A complete study of radio galaxies at z ~ 0.5

Herbert, Peter David January 2013 (has links)
In this thesis I investigate the hosts and cluster environments of a sample of 41 radio galaxies between z = 0.4 and z = 0.6. I use spectroscopic data for a 24 object subsample to investigate their star formation histories via the strength of the 4000A break. I find that the higher radio luminosity or high excitation objects in the sample have evidence for young stellar populations, but the lower radio luminosity or low excitation objects do not. My investigations into the Fundamental Plane (FP) of 18 of the radio galaxies, using the same spectroscopic data as well as data from the literature, show that the Fanaroff- Riley type I objects (FRIs) lie on the FP of local radio galaxies once corrected for passive evolution but the Fanaroff-Riley type II objects (FRIIs) do not. I suggest that an evolution in the size of the host galaxies, aided by a combination of passive evolution and a mass-dependent evolution in the mass-to-light ratios, may explain the observed offsets. Finally, I use wide field multi-band imaging to investigate the cluster environments of the full z ~ 0.5 sample. I find that the environmental overdensity is positively correlated with the radio luminosity and observe a greater number of close companions around the FRIIs than the FRIs (albeit with only nine FRIs in the sample). The cluster environments of the radio galaxies with the greatest host luminosities show tentative evidence for an alignment between the major axis of a galaxy and that of its cluster, whilst there are hints that the objects with the highest radio luminosities have clusters whose major axis is aligned with the position angle of the radio jet. My results suggest a picture in which FRII type radio sources reside in particularly rich cluster environments at z ~ 0.5 but FRI type radio sources in less rich environments. The environment plays a key role in determining both the radio properties of the galaxy and the evolution of its host. The effect of the environment on the emission line properties and star formation histories of the galaxies leads to the overlap seen in the morphological and spectral properties of radio galaxies.
252

Virtual Environments at NCSU Libraries

Boyer, Josh 23 April 2012 (has links)
'Virtual Environments' Breakout session from the Living the Future 8 Conference, April 23-24, 2012, University of Arizona Libraries, Tucson, AZ.
253

Learning Environments - 21st Century Library

Deaton, Patrick, Nutter, Susan, Church-Duran, Jennifer 23 April 2012 (has links)
Breakout session from the Living the Future 8 Conference, April 23-24, 2012, University of Arizona Libraries, Tucson, AZ.
254

Effect of micro-gravity on the microstructural evolution during liquid phase sintering

Tewari, Asim 05 1900 (has links)
No description available.
255

Managing Generation Y in a multigenerational workplace

Ricks, Ryan Summers 22 December 2010 (has links)
The Baby Boomers are retiring and Generation X isn’t large enough to compensate for the lack of manpower in the workforce. Generation Y will fill the manpower void and employers will need to effectively attract, retain and manage them to stay successful in the future. Many Generation Y employees are quitting in the first year and managers are finding it more difficult to retain them. This thesis offers discussion and analysis of common problems associated with managing Generation Y employees and gives solutions and strategies to create a better work environment. / text
256

Barn på väg till utbrändhet : Hur pedagogerna i fritidshem kan hjälpa drabbade barn

Bengtsson, Anna-Karin January 2011 (has links)
No description available.
257

ON THE UTILITY OF EVOLVING FOREX MARKET TRADING AGENTS WITH CRITERIA BASED RETRAINING

Loginov, Alexander 25 March 2013 (has links)
This research investigates the ability of genetic programming to build profitable trad- ing strategies for the Foreign Exchange Market (FX) of one major currency pair (EURUSD) using one hour prices from July 1, 2009 to November 30, 2012. We rec- ognize that such environments are likely to be non-stationary and we do not expect that a single training partition, used to train a trading agent, represents all likely future behaviours. The proposed adaptive retraining algorithm – hereafter FXGP – detects poor trading behaviours and trains a new trading agent. This represents a significant departure from current practice which assumes some form of continuous evolution. Extensive benchmarking is performed against the widely used EURUSD currency pair. The non-stationary nature of the task is shown to result in a prefer- ence for exploration over exploitation. Moreover, adopting a behavioural approach to detecting retraining events is more effective than assuming incremental adaptation on a continuous basis. From the application perspective, we demonstrate that use of a validation partition and Stop-Loss (S/L) orders significantly improves the perfor- mance of a trading agent. In addition the task of co-evolving of technical indicators (TI) and the decision trees (DT) for deploying trading agent is explicitly addressed. The results of 27 experiments of 100 simulations each demonstrate that FXGP sig- nificantly outperforms existing approaches and generates profitable solutions with a high probability.
258

Adaptation to Mega-environments: Introgression of novel alleles for yield using Canadian x Chinese crosses in Soybean

Rossi, Maria Eugenia 13 December 2011 (has links)
The main goal of soybean breeding is to increase yield with improved seed quality characters. The objectives of this thesis were: i) to identify yield quantitative trait loci (QTL) across different mega-environments (ME); ii) to evaluate the relationship between yield and yield components and the co-localization of QTL; iii) to analyze environmental factors that affect QTL expression and identify different ME. Two Canadian x Chinese soybean populations were tested across Canada, northern United States and China. Yield QTL were identified at one, two and three hypothetical ME. Most of them were co-localized with agronomic trait QTL. These results give strong evidence that Canada, northern United States and China are different ME. Novel alleles from plant introductions can favorably contribute directly or indirectly to seed yield and the use of QTL would facilitate their introgression into breeding populations in both North America and China. / National Science and Engineering Research Council of Canada (NSERC) and the Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA)
259

Steady thermocapillary flow between a non-wetting liquid droplet and a solid surface

Wood, Andrea Marie 12 1900 (has links)
No description available.
260

Reactive behaviour for autonomous virtual agents using fuzzy logic

Jaafar, Jafreezal January 2009 (has links)
One of the fundamental aspects of a virtual environment is the virtual agents that inhabit them. In many applications, virtual agents are required to perceive input information from their environment and make decisions appropriate to their task based on their programmed reaction to those inputs. The research presented in this thesis focuses on the reactive behaviour of the agents. We propose a new control architecture to allow agents to behave autonomously in navigation tasks in unknown environments. Our behaviour-based architecture uses fuzzy logic to solve problems of agent control and action selection and which can coordinate conflicts among different operations of reactive behaviours. A Fuzzy Associative Memory (FAM) is used as the process of encoding and mapping the input fuzzy sets to the output fuzzy set and to optimise the fuzzy rules. Our action selection algorithm is based on the fuzzy α-level method with the Hurwicz criterion. The main objective of the thesis was to implement agent navigation from point to point by a coordination of planning, sensing and control. However, we believe that the reactive architecture emerging from this research is sufficiently general that it could be applied to many applications in widely differing domains where real-time decision making under uncertainty is required. To illustrate this generality, we show how the architecture is applied to a different domain. We chose the example of a computer game since it clearly demonstrates the attributes of our architecture: real-time action selection and handling uncertainty. Experimental results are presented for both implementations which show how the fuzzy method is applied, its generality and that it is robust enough to handle different uncertainties in different environments. In summary, the proposed reactive architecture is shown to solve aspects of behaviour control for autonomous virtual agents in virtual environments and can be applied to various application domains.

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