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A Web Site-Level Implementation Of Owl Sameas Predicate In Drupal, Patricia Esparza Jan 2011

A Web Site-Level Implementation Of Owl Sameas Predicate In Drupal, Patricia Esparza

Open Access Theses & Dissertations

The Ontology Web Language (OWL) sameAs predicate states that if the predicate holds between two Uniform Resource Identifiers (URIs) A and B, then an object identified by A is the same object identified by B; its purpose is to enable machines to understand that both objects are the same although they may have distinct Web identifiers, i.e., URIs. The proliferation of the use of this predicate has brought several issues to the Web, e.g., high cost of manually creating sameAs statements, inconsistent use of the predicate leading to distinct objects to be identified as being a single object, and too …


Gpu Based Parallel Smoothing Of Seismic Tomography Models, Ivan Gris Jan 2011

Gpu Based Parallel Smoothing Of Seismic Tomography Models, Ivan Gris

Open Access Theses & Dissertations

Three-dimensional models of the velocity structure of the Earth's crust are an important and relevant factor for several types of analyses across disciplines. Crustal velocity models are also commonly used to analyze and search for different materials of interest or to determine and differentiate many aspects of life on Earth during different eras.

Seismic tomography techniques, both in two and three dimensions, perform image reconstruction of the crust of the Earth. Seismic tomography algorithms can calculate crustal velocity structure through inversion of traveltimes of seismic waves produced by natural events, such as earthquakes, or controlled source experiments, such as explosions. …


Monitoring Ecosystem Dynamics In An Arctic Tundra Ecosystem Using Hyperspectral Reflectance And A Robotic Tram System, Santonu Goswami Jan 2011

Monitoring Ecosystem Dynamics In An Arctic Tundra Ecosystem Using Hyperspectral Reflectance And A Robotic Tram System, Santonu Goswami

Open Access Theses & Dissertations

Global change, which includes climate change and the impacts of human disturbance, is altering the provision and sustainability of ecosystem goods and services. These changes have the capacity to initiate cascading affects and complex feedbacks through physical, biological and human subsystems and interactions between them. Understanding the future state of the earth system requires improved knowledge of ecosystem dynamics and long term observations of how these are being impacted by global change. Improving remote sensing methods is essential for such advancement because satellite remote sensing is the only means by which landscape to continental-scale change can be observed.

The Arctic …


Evidence Of Ancient Rifts Beneath Texas, Keisuke Irie Jan 2011

Evidence Of Ancient Rifts Beneath Texas, Keisuke Irie

Open Access Theses & Dissertations

Continental rifts are defined as geological features where Earth's lithosphere is pulled away by surface expansion of the Earth. Their physiographic features include linear rift valleys associated with active volcanism. Many rifts fail to split a continent and ancient rifts that failed to split can be found by using seismic waves to image these ancient structures. Using seismic data collected by EarthScope USArray stations in Texas, teleseismic receiver functions was calculated and utilized surface wave dispersion curves to simultaneously invert for the 2D velocity structure beneath each seismic station. EarthScope is a scientific program funded by NSF that provides geophysical …


Development Of A Web-Based Geographic Information System For Arctic Science, George Walker Johnson Jan 2011

Development Of A Web-Based Geographic Information System For Arctic Science, George Walker Johnson

Open Access Theses & Dissertations

Environmental science is a large field of study that requires the acquisition of data for decision making in solving environmental issues. Leveraging desktop geographic information systems (GIS) and web-based GIS (WebGIS) systems for assisting in the problem solving processes can benefit both the research community and policy makers for decision making activities. Ensuring interoperability between desktop, web, and server GIS is essential for maximizing access, sharing and manipulation of data. Interoperability is maximized through the adoption of best practices, use of open standards, and utilization of Spatial Data Infrastructures (SDI). While many of the interoperability challenges such as infrastructure, data …


On Constrained Optimization Schemes For Joint Inversion Of Geophysical Datasets, Uram Anibal Sosa Aguirre Jan 2011

On Constrained Optimization Schemes For Joint Inversion Of Geophysical Datasets, Uram Anibal Sosa Aguirre

Open Access Theses & Dissertations

In the area of geological sciences, there exist several experimental techniques used to advance in the understanding of the Earth. We implement a joint inversion least-squares (LSQ) algorithm to characterize one dimensional Earth's structure by using seismic shear wave velocities as a model parameter. We use two geophysical datasets sensitive to shear velocities, namely Receiver Function and Surface Wave dispersion velocity observations, with a choice of an optimization method: Truncated Singular Value Decomposition (TSVD) or Primal-Dual Interior-Point (PDIP). The TSVD and the PDIP methods solve a regularized unconstrained and a constrained minimization problem, respectively. Both techniques include bounds into the …


Specification Of Data Properties To Identify Anomalies In Scientific Sensor Data, Irbis Gallegos Jan 2011

Specification Of Data Properties To Identify Anomalies In Scientific Sensor Data, Irbis Gallegos

Open Access Theses & Dissertations

Environmental scientists use advanced sensor technology such as meteorological towers, wireless sensor networks and robotic trams equipped with sensors to perform data collection at remote research sites. Because the amount of environmental sensor data acquired by such instruments is increasing, the ability to evaluate the accuracy of the data at collection time and to check that the instrumentation is operating correctly become critical in order to not lose valuable time and information. The goal of the research is to define a solution, based on software-engineering techniques, to support the scientist's ability to specify data properties that can identify anomalies in …


Development Of A Low-Cost Network Of Webcams For Monitoring Plant Phenology In A Chihuahuan Desert Shrubland, Libia Gonzalez Jan 2011

Development Of A Low-Cost Network Of Webcams For Monitoring Plant Phenology In A Chihuahuan Desert Shrubland, Libia Gonzalez

Open Access Theses & Dissertations

Phenology is the study of the timing of natural events such as the schedule of plant life-cycle events like bud burst, flowering, seed set and senescence. Many factors control plant phenological dynamics including climate. As such, phenology has been shown in published literature to be one of the best biological indicators of climate variability and change. Recent advantages in digital photography and digital image processing have opened new opportunities for inexpensive, repeatable and automated capture of plant and landscape phenological dynamics. This technology, however, remains poorly studied in terms of its capacity to depict the development of different plant phenophases, …