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Multi-Satellite Formation Trajectory Design With Topological Constraints Over A Region Of Interest Using Differential Evolution, David William Hinckley Jan 2015

Multi-Satellite Formation Trajectory Design With Topological Constraints Over A Region Of Interest Using Differential Evolution, David William Hinckley

Graduate College Dissertations and Theses

Satellite formation missions allow for scientific measurement opportunities that are only otherwise possible with the use of unrealistically large satellites. This work applies the Evolutionary Algorithm (EA), Differential Evolution (DE), to a 4-satellite mission design that borrows heavily from the mission specifications for Phase 1 of NASA's Magnetospheric Multi-Scale Mission (MMS). This mission specifies goals for formation "quality" and size over the arc when scientific measurements are to be taken known as the Region of Interest (ROI). To apply DE to this problem a novel definition of fitness is developed and tailored to trajectory problems of the parameter scales of …


Reverse Engineering The Human Brain: An Evolutionary Computation Approach To The Analysis Of Fmri, Nicholas Allgaier Jan 2015

Reverse Engineering The Human Brain: An Evolutionary Computation Approach To The Analysis Of Fmri, Nicholas Allgaier

Graduate College Dissertations and Theses

The field of neuroimaging has truly become data rich, and as such, novel analytical methods capable of gleaning meaningful information from large stores of imaging data are in high demand. Those methods that might also be applicable on the level of individual subjects, and thus potentially useful clinically, are of special interest. In this dissertation we introduce just such a method, called nonlinear functional mapping (NFM), and demonstrate its application in the analysis of resting state fMRI (functional Magnetic Resonance Imaging) from a 242-subject subset of the IMAGEN project, a European study of risk-taking behavior in adolescents that includes longitudinal …


An Embodied Approach To Evolving Robust Visual Classifiers, Karol Zieba Jan 2015

An Embodied Approach To Evolving Robust Visual Classifiers, Karol Zieba

Graduate College Dissertations and Theses

From the very creation of the term by Czech writer Karel Capek in 1921, a "robot" has been synonymous with an artificial agent possessing a powerful body and cogitating mind. While the fields of Artificial Intelligence (AI) and Robotics have made progress into the creation of such an android, the goal of a cogitating robot remains firmly outside the reach of our technological capabilities. Cognition has proved to be far more complex than early AI practitioners envisioned. Current methods in Machine Learning have achieved remarkable successes in image categorization through the use of deep learning. However, when presented with novel …


Grass-Based Dairy In Vermont: Benefits, Barriers, And Effective Public Policies, Serge William Wiltshire Jan 2015

Grass-Based Dairy In Vermont: Benefits, Barriers, And Effective Public Policies, Serge William Wiltshire

Graduate College Dissertations and Theses

A comprehensive literature review was undertaken in order to define and assess the sustainability and resiliency characteristics associated with grass-based and confinement dairy farming. Primarily as a result of reduced input costs, grass-based dairy farming often enhances profitability over confinement systems, especially on small farms. Further, conversion of tilled soil to permanent pasture has been shown to significantly reduce harmful sediment and nutrient transport into waterways. Perennial forage also acts as a carbon sink, curtailing or even negating a grass-based farm's carbon footprint. Finally, social benefits derived from enhanced nutrition and higher quality of life are also associated with grass-based …


Gene Expression Noise In Stress Response As A Survival Strategy In Fluctuating Environments, Javier Garcia-Bernardo Jan 2015

Gene Expression Noise In Stress Response As A Survival Strategy In Fluctuating Environments, Javier Garcia-Bernardo

Graduate College Dissertations and Theses

Populations of cells live in uncertain environments, where they encounter large variations in nutrients, oxygen and toxic compounds. In the fluctuating environment, cells can sense their surroundings and express proteins to protect themselves against harmful substances. However, if the stressor appears infrequently or abruptly, sensing can be too costly or too slow, and cells cannot rely solely on it. To hedge against the sudden appearance of a stressor, cell populations can also rely on phenotypic diversification through bet-hedging. In bet-hedging, cells exploit noise in gene expression or use multistable genetic networks to produce an heterogeneous distribution of resistance-conferring protein levels. …


Exploring The Google Books Corpus: An Information-Theoretic Approach To Linguistic Evolution, Eitan Pechenick Jan 2015

Exploring The Google Books Corpus: An Information-Theoretic Approach To Linguistic Evolution, Eitan Pechenick

Graduate College Dissertations and Theses

The Google Books corpus contains millions of books in a variety of languages. Due to this incredible volume and its free availability, it is a treasure trove that has inspired a plethora of linguistic research.

It is tempting to treat frequency trends from Google Books data sets as indicators for the true popularity of various words and phrases. Doing so allows us to draw novel conclusions about the evolution of public perception of a given topic. However, sampling published works by availability and ease of digitization leads to several important effects, which have typically been overlooked in previous studies. One …