Geography Commons^™

Satellite Remote Sensing For Measuring The Urban Forest Of Portland, Oregon, A. Paul Newman

Dissertations and Theses

Digital pattern recognition methods were used to produce two maps of urban vegetation from LANDSAT Thematic Mapper for the City of Portland, Oregon. The image was acquired on July 7, 1991 and the spectral bands used were 2, 4, 5 and a ratio of 3 and 4. The two maps represent vegetation amount and vegetation type.

Due to the extreme heterogeneous nature of the urban environment, these maps were developed using techniques to reduce and manage the amount of spectral variation. This included purging non-vegetated cells from the multispectral image, and then stratifying the image into "spectral subdivisions" using tools …

Observation Of Shelfwater Overrunning The Southern Slope Sea, Ajoy Kumar

OES Theses and Dissertations

Analyses of two years (1992 and 1993) of high resolution (1.47 km²) sea surface temperature satellite images of the southern Mid-Atlantic Bight (MAB), showed that unusually extensive overhang of shelf water occurs episodically, and coherently over along shelf distances of several hundred kilometers. These episodes are dubbed overrunning of the Slope Sea by shelf water. The overrunning volume has a "face" and a "back" (southern and northern limit). It transports substantial quantities of shelf water southward, and does not retreat onto the shelf, but eventually joins the western edge of the Gulf Stream in the vicinity of Chesapeake …

Autonomous Robot Navigation In Unknown Terrains Using Parallel Numerical Artificial Potential Fields, John C. Schneider

Computer Science Theses & Dissertations

We present a new artificial potential field formulation for resolution complete robot navigation that unifies the purely geometric path planning problem with the lower level force control problem. Our formulation is designed for numerical computation over a massively parallel mesh of processors and is responsive to newly discovered terrain features. It does not suffer from many of the problems commonly associated with potential fields and with adequate resolution provides provably correct, collision free convergence to the goal. In addition, our formulation supports many desirable, practical features required for implementation, such as bounded actuator torques, attainable incremental constructability, realizable computation and …

Flow Kinematics And Dynamics Of The Gulf Stream From Composite Imagery, Caitlin Patrice Mullen

OES Theses and Dissertations

A unique set of contemporaneous satellite-tracked drifters and five-day composite satellite images of the North Atlantic is studied in order to infer the near-surface flow kinematics and dynamics of the Gulf Stream. Using fractal and spectral analyses, two kinematic models, and a potential vorticity model, detailed comparisons are made between these data sets.

Fractal and spectral analyses show that the data set is not fractal, there is no geographic variability, and there is not a strong fractal scaling link between the drifter trajectories and composite temperature fronts as had been postulated by several investigators. These results indicate considerably more work …

Binary Programming Models Of Spatial Pattern Recognition: Applications In Remote Sensing Image Analysis, Thomas G. Reed

Theses and Dissertations

The major purpose of this investigation was to implement subregion allocation objectives using a network model base on an existing subregion allocation binary programming model (Benabdallah and Wright (B&W), 1990), the ultimate goal being the application of subregion allocation concepts towards the spatial analysis of satellite imagery. The multi-objective aspects of subregion allocation can be accomplished via a network formulation, a formulation vastly simpler in complexity than the binary programming models previously used. Without a network programming package that could maintain integral flows, however, deriving the solution was a tiresome task for the user. Nonetheless, several new concepts and advantages …

Design Of A Reliable, Inexpensive Recording Rain Gage Which Utilizes Solid-State Memory, Stephen A. Dyer

KWRRI Research Reports

Researchers working in the general area of water resources frequently have need for precipitation data. Unfortunately, the cost of commercially available recording rain gages is often greater than $1,000 per unit. This report describes a microprocessor-controlled remote recording rain gage which is capable of unattended operation for periods of greater than a month that costs less than $400 in single quantities. The laboratory prototype uses a tipping bucket to collect precipitation in 0.01-inch increments. The time of the bucket tip is stored, using an offset binary format, in solid-state memory. A complete description of the gage hardware is presented along …