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Theses/Dissertations

2012

Time series

Articles 1 - 5 of 5

Full-Text Articles in Physical Sciences and Mathematics

Topographic Influences On Trends And Cycles In Nutrient Export From Forested Catchments On The Precambrian Shield, Samson G. Mengistu Dec 2012

Topographic Influences On Trends And Cycles In Nutrient Export From Forested Catchments On The Precambrian Shield, Samson G. Mengistu

Electronic Thesis and Dissertation Repository

This dissertation explored topographic controls on spatial and temporal patterns in water yield and nutrient (carbon, nitrogen and phosphorus) export from forested headwater catchments in the Turkey Lakes Watershed in central Ontario, where other factors contributing to differences in water yield and nutrient export, including climate, geology, forest, and soils, are relatively constant. Topographic characteristics, including (a) hydrological flushing potential (expansion of water table into nitrate-N producing areas); (b) hydrological storage potential (area of wetlands, which can alternatively allow water and nutrients to bypass wetlands when storage capacity is filled with water or to trap them when not filled); and …

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Visual Data Mining Techniques For Functional Actigraphy Data: An Object-Oriented Approach In R, Abbass Sharif Dec 2012

Visual Data Mining Techniques For Functional Actigraphy Data: An Object-Oriented Approach In R, Abbass Sharif

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Actigraphy, a technology for measuring a subject's overall activity level almost continuously over time, has gained a lot of momentum over the last few years. An actigraph, a watch-like device that can be attached to the wrist or ankle of a subject, uses an accelerometer to measure human movement every minute or even every 15 seconds. Actigraphy data is often treated as functional data. In this dissertation, we discuss what has been done regarding the visualization of actigraphy data, and then we will explain the three main goals we achieved: (i) develop new multivariate visualization techniques for actigraphy data; (ii) …

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A Time Series Analysis Method Using Hidden Variables For Gene Network Reconstruction, Xi Wu Dec 2012

A Time Series Analysis Method Using Hidden Variables For Gene Network Reconstruction, Xi Wu

Dissertations

The DNA microarray technology can be applied to obtain time series data which contains thousands of genes and tens of time points. When confront the great amount of data points a fast and effective method must be constructed to extract useful information. The assumption that the interactions between genes are static in the time series data is made. After made the assumption how to reconstruct those interactions becomes a difficulty problem. Since the underlying interactions between genes are complicated, which involve transcription, translation and protein-protein interaction, to construct a model from physicochemistry is almost impossible/effortless. The popular methods constructed from …

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A Stochastic Parameter Regression Approach For Time-Varying Relationship Between Gold And Silver Prices, Birsen Canan-Mcglone Aug 2012

A Stochastic Parameter Regression Approach For Time-Varying Relationship Between Gold And Silver Prices, Birsen Canan-Mcglone

Boise State University Theses and Dissertations

In this thesis, we studied the gold and silver relationship using stochastic-parameter regression models. We formulated their time-varying relationship as a state-space model and used the Kalman filter algorithm to estimate the stochastic regression parameters for gold and silver prices. The data set used in this thesis covers 31 years using the London fix prices between January 1969 and December 2000. The start date was selected as the first full year silver prices were included in the London fix prices. Our stochastic parameter regression model explained well the time-varying relationship between gold and silver prices. As a special case of …

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Spatial And Temporal Variability Of Remotely Sensed Ocean Color Parameters In Coral Reef Regions, Daniel Brooks Otis Jan 2012

Spatial And Temporal Variability Of Remotely Sensed Ocean Color Parameters In Coral Reef Regions, Daniel Brooks Otis

USF Tampa Graduate Theses and Dissertations

The variability of water-column absorption due to colored dissolved organic matter (CDOM) and phytoplankton in coral reef regions is the focus of this study. Hydrographic and CDOM absorption measurements made on the Bahamas Banks and in Exuma Sound during the spring of 1999 and 2000 showed that values of salinity and CDOM absorption at 440nm were higher on the banks (37.18 psu, 0.06 m^-1), compared to Exuma Sound (37.04 psu, 0.03 m^-1). Spatial patterns of CDOM absorption in Exuma Sound revealed that plumes of CDOM-rich water flow into Exuma Sound from the surrounding banks. To examine absorption variability in reef …

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