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Physical Sciences and Mathematics Commons

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Utah State University

Utah Space Grant Consortium

1997

Articles 1 - 11 of 11

Full-Text Articles in Physical Sciences and Mathematics

Time-Based Clustering And Its Relationship With Mutual Information Theory, Charles R. Tolle Jun 1997

Time-Based Clustering And Its Relationship With Mutual Information Theory, Charles R. Tolle

Utah Space Grant Consortium

This paper re-introduces the concepts of TimeBased Clustering (TBC). Also, the ideas of oversampling and embedding time are introduced in connection with mutual information theory. These concepts are then extended through the use of the Time-Based Clustering (TBC) problem. Mutual information curves for the Rössler system are shown to match a slice through the rich cost function space spanned by the Time-Based Clustering (TBC) solution. In closing, some possible repercussions of this find are discussed.


Examination Of The Combustion Morphology Of Ziconium Carbide Using Scanning Electron Microscopy, Brian R. Newbold Jun 1997

Examination Of The Combustion Morphology Of Ziconium Carbide Using Scanning Electron Microscopy, Brian R. Newbold

Utah Space Grant Consortium

Calculation of viscous particle damping of acoustic combustion instability in solid propellant motors requires an understanding of the combustion behavior of added particles and oxides. A simple hydrogen/oxygen flame was used to ignite carefully sieved zirconium carbide particles which were impacted on slides at different levels below the burner.

Scanning electron microscopy revealed that zirconium carbide has a complex heterogeneous combustion morphology. Initially, particles are partly vitreous and crystalline with a complex surface area. Upon ignition, particles round, but soon wrinkle as zirconium oxide deposits on the surface. Such morphology information is useful to refine viscous damping calculations.


Gps Tracking For Small Sounding Rockets, Darin K. Fowers Jun 1997

Gps Tracking For Small Sounding Rockets, Darin K. Fowers

Utah Space Grant Consortium

Active areas of research often create the need for improved technology to make observations in a way that has not previously been utilized. Such is the case with middle atmospheric research. This 60 to 120 km region of the atmosphere is too low to be directly probed by satellites and too high to be probed by research airplanes or high altitude balloons. Sounding rockets are the only vehicle that can carry instruments for in situ measurements. Up until now only a few methods have been available to track the location of a sounding rocket - radar skin tracking, radio beacon …


Absolute Solar Transmittance Interferometer, Arthur W. Dybdahl Jun 1997

Absolute Solar Transmittance Interferometer, Arthur W. Dybdahl

Utah Space Grant Consortium

The University of Denver's Absolute Solar Transmittance Interferometer (ASTI) has been developed to make high-resolution infrared (TR) radiometric measurements of the incident solar radiance and irradiance at the Earth's surface. It is a research instrument that provides spectral data of high scientific interest in the short-wave infrared (SWIR) band covering 0.97 to 5.13 µm. This band contains about 20 percent of the suns incident energy, having a significant impact on global as well as regional climate. ASTI spectra are used to provide significant radiometric information describing the SWlR transmittance and absorption properties of the atmosphere. The ASTl research program and …


Flow Past Bluff Bodies, Thad S. Morton Jun 1997

Flow Past Bluff Bodies, Thad S. Morton

Utah Space Grant Consortium

More than a century ago Kirchhoff solved for the velocity distribution within an elliptical patch of uniform vorticity. That solution became the basis for all further studies of elliptical vortices and has been regarded as the only known exact solution for a steady, elliptical patch of uniform vorticity. In the present paper, an exact solution for a new elliptical patch of uniform vorticity is presented. The vortex is constructed of streamlines of constant eccentricity. By specifying a velocity distribution along either of the principle axes of the vortex, continuity between differentially-spaced streamlines provides the velocity distribution throughout the vortex. Some …


Internet Access For Instrumental Control And Data Viewing At Bear Lake Observatory, Kerry M. Nelson Jun 1997

Internet Access For Instrumental Control And Data Viewing At Bear Lake Observatory, Kerry M. Nelson

Utah Space Grant Consortium

Two departments at Utah State University have collaborated to operate an observatory near Bear Lake, Utah. The purpose of the observatory is to study various phenomena in the upper atmosphere, and houses such instruments as high-power CCD cameras, a radar system, and others. Until recently, only one instrument has had the capability of being controlled and monitored remotely. Since the other instruments do not have this capability, they must be set up and left running, only to have a person drive up to the observatory to check their operation after a given amount of time. This monitoring system is not …


Microgravity Effects On Water Flow And Distribution In Unsaturated Porous Media, Scott B. Jones, Dani Or Jun 1997

Microgravity Effects On Water Flow And Distribution In Unsaturated Porous Media, Scott B. Jones, Dani Or

Utah Space Grant Consortium

Several aspects of the physical processes of liquid flow and distribution within partially saturated porous media are altered in the reduced gravity conditions (microgravity) of orbiting spacecraft. The objectives of this study were to simulate and test measured flow and distribution in porous media from a microgravity environment using conventional capillary flow theory. Two past microgravity experiments studying water supply and uptake in porous media took place on a U.S. space shuttle, titled ASC-1, and on the Russian space station Mir, titled Greenhouse-2. Data from microgravity and ground experiments were simulated using similar physical flow models by elimination of the …


Validation Study Of A Novel Neonatal Pneumotach, Scott A. Kofoed Jun 1997

Validation Study Of A Novel Neonatal Pneumotach, Scott A. Kofoed

Utah Space Grant Consortium

We have developed a pneumotach for measuring respiratory gas flows in humans and or animals. The pneumotach enables the monitoring of respiratory and metabolic function in human subjects over extended periods of time. A bench study was conducted to validate the new pneumotach system against other predicate devices. The pneumotach under test compared well to the predicate devices used.


Binary Classification Of Wind Fields Through Hypothesis Testing On Scatterometer Measurements, Paul E. Johnson Jun 1997

Binary Classification Of Wind Fields Through Hypothesis Testing On Scatterometer Measurements, Paul E. Johnson

Utah Space Grant Consortium

Scatterometers are radars specially designed to nearsurface wind over the ocean from space. Traditional scatterometer wind estimation inverts the model function relationship between the wind and backscatter at each resolution element, yielding a set of ambiguities due to the many-to-one mapping of the model function. Field-wise wind estimation dramatically reduces the number of ambiguities by estimating the wind at many resolution elements, simultaneously, using a wind model that constrains the spatial variability of the wind. However, the appropriate choice of the model order needed for a particular wind field is not known a priori. The approximate model order is valuable …


Temporal Change Enhancement In Multispectral Images Remotely Sensed From Satellites, William P. Pfaff Jun 1997

Temporal Change Enhancement In Multispectral Images Remotely Sensed From Satellites, William P. Pfaff

Utah Space Grant Consortium

The application of principal components analysis to multispectral satellite images is a routine way to present the data in false-color composite images. These composite images include a very high percentage of available information and have no correlation between the displayed colors. The transformation of multispectral image data into its principal components is also an effective way to separate image information from noise. This paper describes a procedure for temporal change enhancement which exploits both the decorrelation and noise isolation properties of the principal components transformation. Using simulated temporal change, this procedure was demonstrated to be more effective than the standard …


Development Of A Full-Spectrum Raman Device For Detection Of Environmental Contaminants, David G. Smith Jun 1997

Development Of A Full-Spectrum Raman Device For Detection Of Environmental Contaminants, David G. Smith

Utah Space Grant Consortium

NASA needs sensors to accurately monitor the water and atmospheric quality in its space habitat. Concerns for health and safety necessitate the development of sensors to measure common atmospheric gas concentrations, as well as trace contaminants (low ppm or ppb), including both combustible and noncombustible gases. The University of Utah is developing an enhanced Raman monitoring system to detect airborne, environmental contaminants. We have collected laboratory data to benchmark current laser Raman technology for gas analysis, which provides a reference for future developments. The objective of this project was to design a prototype gas-phase monitor, incorporating new technology that would …