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  Partner: UNT Libraries Government Documents Department
 Decade: 1990-1999
3-D Silicon Photonic Lattices- Cornerstone of an Emerging Photonics Revolution

3-D Silicon Photonic Lattices- Cornerstone of an Emerging Photonics Revolution

Date: July 8, 1999
Creator: Fleming, J.G. & Lin, Shawn-Yu
Description: Three-dimensional photonic lattices are engineered materials which are the photonic analogues of semiconductors. These structures were first proposed and demonstrated in the mid-to-late 1980's. However, due to fabrication difficulties, lattices active in the infrared are only just emerging. Wide ranges of structures and fabrication approaches have been investigated. The most promising approach for many potential applications is a diamond-like structure fabricated using silicon microprocessing techniques. This approach has enabled the fabrication of 3-D silicon photonic lattices active in the infrared. The structures display band gaps centered from 12{micro} down to 1.55{micro}.
Contributing Partner: UNT Libraries Government Documents Department
3-D Spectral Induced Polarization (IP) Imaging: Non-Invasive Characterization Of Contaminant Plumes

3-D Spectral Induced Polarization (IP) Imaging: Non-Invasive Characterization Of Contaminant Plumes

Date: June 1, 1997
Creator: Morgan, Dale F.; Lesmes, David P.; Rodi, William; Shi, Weiqun; Frye, Kevin, M. & Sturrock, John
Description: The overall objective of this project is to develop the scientific basis for characterizing contaminant plumes in the earth's subsurface using field measurements of induced polarization (IP) effects. Three specific objectives towards this end are 1. 2. 3. Understanding IP at the laboratory level through measurements of complex resistivity as a function of frequency in rock and soil samples with varying pore geometries, pore fluid conductivities and saturations, and contaminant chemistries and concentrations. Developing effective data acquisition techniques for measuring the critical IP responses (time domain or frequency domain) in the field. Developing modeling and inversion algorithms that permit the interpretation of field IP data in terms of subsurface geology and contaminant plume properties.
Contributing Partner: UNT Libraries Government Documents Department
3-D Spectral IP Imaging: Non-Invasive Characterization of Contaminant Plumes

3-D Spectral IP Imaging: Non-Invasive Characterization of Contaminant Plumes

Date: June 1, 1998
Creator: Morgan, F. Dale; Rodi, William & Lesmes, David
Description: The overall objective of this project is to develop the scientific basis for characterizing contaminant plumes in the earth's subsurface using field measurements of induced polarization (IP) effects. Three specific objectives towards this end are: (1) Understanding IP at the laboratory level through measurements of complex resistivity as a function of frequency in rock and soil samples with varying pore geometries, pore fluid conductivities and saturations, and contaminant chemistries and concentrations. (2) Developing effective data acquisition techniques for measuring the critical IP responses (time domain or frequency domain) in the field. (3) Developing modeling and inversion algorithms that permit the interpretation of field IP data in terms of subsurface geology and contaminant plume properties.
Contributing Partner: UNT Libraries Government Documents Department
3-D spectral IP imaging: Non-invasive characterization of contaminant plumes. 1998 annual progress report

3-D spectral IP imaging: Non-invasive characterization of contaminant plumes. 1998 annual progress report

Date: June 1, 1998
Creator: Morgan, F.D.; Rodi, W. & Lesmes, D.
Description: 'The overall objective of this project is to develop the scientific basis for characterizing contaminant plumes in the earth''s subsurface using field measurements of induced polarization (IP) effects. Three specific objectives towards this end are: (1) understanding IP at the laboratory level through measurements of complex resistivity as a function of frequency in rock and soil samples with varying pore geometries, pore fluid conductivities and saturations, and contaminant chemistries and concentrations; (2) developing effective data acquisition techniques for measuring the critical IP responses (time domain or frequency domain) in the field; (3) developing modeling and inversion algorithms that permit the interpretation of field IP data in terms of subsurface geology and contaminant plume properties. The authors laboratory experiments to date are described in Appendices A and B, which consist of two papers submitted to the annual SAGEEP conference (Frye et al., 1998; Sturrock et al., 1998). The experiments involved measurements of complex resistivity vs. frequency on a suite of brine saturated sandstone samples. In one set of experiments, the fluid chemistry (pH, ionic strength, and cation type) was varied. In a second set of experiments, the microgeometry of the rock matrix was varied. The experiments showed that spectral IP responses ...
Contributing Partner: UNT Libraries Government Documents Department
3-D spectral IP imaging: Non-invasive characterization of contaminant plumes. Annual progress report, September 15, 1996--September 14, 1997

3-D spectral IP imaging: Non-invasive characterization of contaminant plumes. Annual progress report, September 15, 1996--September 14, 1997

Date: December 1, 1997
Creator: Frye, K.M.; Lesmes, D.P.; Morgan, F.D.; Rodi, W.; Shi, W. & Sturrock, J.
Description: 'The objective of this project is to develop the scientific basis for characterizing contaminant plumes in the earth''s subsurface using field measurements of induced polarization (IP) effects. The first-year accomplishments are (1) laboratory experiments on fluid-saturated sandstones quantifying the dependence of spectral IP responses on solution chemistry and rock micro-geometry; (2) library research on the current understanding of electromagnetic coupling effects on IP data acquired in the field: and (3) development of prototype forward modeling and inversion algorithms for interpreting IP data in terms of 3-D models of complex resistivity.'
Contributing Partner: UNT Libraries Government Documents Department
3-D Target Location from Stereoscopic SAR Images

3-D Target Location from Stereoscopic SAR Images

Date: October 1, 1999
Creator: Doerry, Armin W.
Description: SAR range-Doppler images are inherently 2-dimensional. Targets with a height offset lay over onto offset range and azimuth locations. Just which image locations are laid upon depends on the imaging geometry, including depression angle, squint angle, and target bearing. This is the well known layover phenomenon. Images formed with different aperture geometries will exhibit different layover characteristics. These differences can be exploited to ascertain target height information, in a stereoscopic manner. Depending on the imaging geometries, height accuracy can be on the order of horizontal position accuracies, thereby rivaling the best IFSAR capabilities in fine resolution SAR images. All that is required for this to work are two distinct passes with suitably different geometries from any plain old SAR.
Contributing Partner: UNT Libraries Government Documents Department
3-D vertical seismic profiling at LLNL Site 300

3-D vertical seismic profiling at LLNL Site 300

Date: January 29, 1997
Creator: Bainer, R.; Rector, J. & Milligan, P.
Description: The initial goal of the 3-D Vertical Seismic Profiling (VSP) work at LLNL was to characterize seismic wave velocities and frequencies below the vadose zone to design the acquisition geometry for a 3-D shallow surface seismic reflection survey. VSPs are also used routinely to provide a link between surface seismic data and well logs. However, a test 2-D seismic line recorded at LLNL in the Spring of 1994 indicated that obtaining high quality reflection images below the vadose zone, yet shallower that 50 m, would require an expensive, very finely sampled survey ({lt} 1 m receiver spacing). Extensive image processing of the LLNL 2-D test line indicated that the only reliable reflection was from the top of the water table. Surprisingly, these results were very different than recent 3-D seismic work recorded at other sites, where high quality, high frequency surface (up to 300 Hz) reflection images were obtained as shallow as 20m. We believe that the differences are primarily due to the comparatively deep vadose zone at LLNL (15 to 30m) as compared to 0-5m at other sites. The thick vadose zone attenuates the reflection signals, particularly at the high frequencies (above 100 @). In addition, the vadose zone ...
Contributing Partner: UNT Libraries Government Documents Department
3-D woven, mullite matrix, composite filter

3-D woven, mullite matrix, composite filter

Date: December 1, 1995
Creator: Lane, J.E.; Painter, C.J. & Radford, K.C. LeCostaouec, J.F.
Description: Westinghouse, with Techniweave as a major subcontractor, is conducting a three-phase program aimed at providing advanced candle filters for a 1996 pilot scale demonstration in one of the two hot gas filter systems at Southern Company Service`s Wilsonville PSD Facility. The Base Program (Phases I and II) objective is to develop and demonstrate the suitability of the Westinghouse/Techniweave next generation composite candle filter for use in Pressurized Fluidized Bed Combustion (PFBC) and/or Integrated Gasification Combined Cycle (IGCC) power generation systems. The Optional Task (Phase M, Task 5) objective is to fabricate, inspect and ship to Wilsonville Hot gas particulate filters are key components for the successful commercializaion of advanced coal-based power-generation systems such as Pressurized Fluidized-bed Combustion (PFBC), including second-generation PFBC, and Integrated Gasification Combined Cycles (IGCC). Current generation monolithic ceramic filters are subject to catastrophic failure because they have very low resistance to crack propagation. To overcome this problem, a damage-tolerant ceramic filter element is needed.
Contributing Partner: UNT Libraries Government Documents Department
A 3-dimensional ray-trace model for predicting the performance of flashlamp-pumped laser amplifiers

A 3-dimensional ray-trace model for predicting the performance of flashlamp-pumped laser amplifiers

Date: February 13, 1997
Creator: Jancaitis, K.S.; Haney, S.W.; Munro, D.H.; Le Touze, G. & Cabourdin, O.
Description: We have developed a fully three-dimensional model for the performance of flashlamp pumped laser amplifiers. The model uses a reverse ray-trace technique to calculate the pumping of the laser glass by the flashlamp radiation. We have discovered several different methods by which we can speed up the calculation of the gain profile in a amplifier. The model predicts the energy-storage performance of the Beamlet amplifiers to better than 5%. This model will be used in the optimization of the National Ignition Facility (NIF) amplifier design.
Contributing Partner: UNT Libraries Government Documents Department
3-dimensional wells and tunnels for finite element grids

3-dimensional wells and tunnels for finite element grids

Date: April 1, 1996
Creator: Cherry, T.A.; Gable, C.W. & Trease, H.
Description: Modeling fluid, vapor, and air injection and extraction from wells poses a number of problems. The length scale of well bores is centimeters, the region of high pressure gradient may be tens of meters and the reservoir may be tens of kilometers. Furthermore, accurate representation of the path of a deviated well can be difficult. Incorporating the physics of injection and extraction can be made easier and more accurate with automated grid generation tools that incorporate wells as part of a background mesh that represents the reservoir. GEOMESH is a modeling tool developed for automating finite element grid generation. This tool maintains the geometric integrity of the geologic framework and produces optimal (Delaunay) tetrahedral grids. GEOMESH creates a 3D well as hexagonal segments formed along the path of the well. This well structure is tetrahedralized into a Delaunay mesh and then embedded into a background mesh. The well structure can be radially or vertically refined and each well layer is assigned a material property or can take on the material properties of the surrounding stratigraphy. The resulting embedded well can then be used by unstructured finite element models for gas and fluid flow in the vicinity of wells or tunnels. ...
Contributing Partner: UNT Libraries Government Documents Department