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First Assessment of Computations of Turbulent Bubbly Flow and Particulate Flow with the COMMIX-M Program

Description: The COMMIX-M computer code, which describes steady-state and transient single- and multi-component flows in engineering systems, has been implemented to simulate suspension flows in laminar regimes and turbulent and bubbly particulate flows. This report presents a synopsis of the present code's capabilities, with particular emphasis on the recent development of turbulence models, and explains in detail the modifications necessary to simulate particulate flows and bubbly flows. First results of … more
Date: May 1994
Creator: Bottoni, M.; Chang, F. C. & Ding, J.
Item Type: Refine your search to only Report
open access

Critical Review of Glass Performance Modeling

Description: Borosilicate glass is to be used for permanent disposal of high-level nuclear waste in a geologic repository. Mechanistic chemical models are used to predict the rate at which radionuclides will be released from the glass under repository conditions. The most successful and useful of these models link reaction path geochemical modeling programs with a glass dissolution rate law that is consistent with transition state theory. These models have been used to simulate several types of short-term l… more
Date: July 1994
Creator: Bourcier, William L.
Item Type: Refine your search to only Report
open access

The Hawaiian Monk Seal, Monachus schauinslandi, at Kure Atoll, 1982-83

Description: This report describes an observational research on the population of the Hawaiian monk seal at Kure Atoll taken from the March to October of 1982 to the April to June of 1983. The study focuses on deaths, injuries, reproduction rates, and data gathered during seal captivity.
Date: February 1991
Creator: Bowlby, C. Edward; Scoggins, Penelope D.; Watson, Rodney T. & Reddy, Michelle L.
Item Type: Refine your search to only Report
open access

The Kewalo Research Facility: on the Forefront for More than 40 Years

Description: The following report provides extensive information on the Kewalo Research Facility of Oahu Island. The Kewalo Research Facility sits on Kewalo Basin and is the center for ongoing research programs designed to examine the most important environmental parameters on the behavior and physiology of tunas. Along with tuna the Kewalo Research facility is also a primary location to stage research activities associated with the studies and preservation of the Hawaiian monk seals, it also provides an im… more
Date: October 1999
Creator: Brill, Richard W.
Item Type: Refine your search to only Report
open access

Petrographic and Geochemical Analyses of Leach Samples from Artillery Peak, Mohave County, Arizona

Description: Abstract: The first step in determining whether Mn can be recovered by in situ leaching is to develop and test a selective lixiviant. Two column leach tests and one core leach test were conducted by the U.S. Bureau of Mines on Mn oxide ore using aqueous sulfur dioxide (SO2) as the lixiviant. The column tests showed that aqueous SO2 could selectively dissolve available Mn oxides from calcite-rich ore in a heap leach system. However, the core test showed that calcite gangue side reactions can hav… more
Date: 1995
Creator: Brink, Susan E.; Blake, Rolland & Marozas, Dianne
Item Type: Refine your search to only Report
open access

LEVSEEP: Analysis Software for Levee Underseepage and Rehabilitation

Description: This report uses the computer software LEVSEEP to describe analysis methodology for levee underseepage analyses and rehabilitation. Information required for data input, calculation procedures, output, and graphics is presented. In addition, comprehensive results of case studies and parameter analyses utilizing LEVSEEP are included.
Date: July 1995
Creator: Brizendine, Anthony L.; Taylor, Hugh M., Jr. & Gabr, M. A.
Item Type: Refine your search to only Report
open access

Sedimentology and Depositional History of the Lower Paleocene Tullock Member of the Fort Union Formation, Powder River Basin, Wyoming and Montana

Description: From abstract: This report is a study on the history of sedimentology and deposition of the lower Paleocene Tullock Member of the Fort Union Formation, Powder River Basin, Wyoming and Montana while looking at the geometry and sedimentary structures.
Date: 1993
Creator: Brown, Janet L.
Item Type: Refine your search to only Report
open access

Analytical Electron Microscopy Characterization of Fernald soils. Annual Report, October 1993 - September 1994

Description: A combination of backscattered electron imaging and analytical electron microscopy (AEM) with electron diffraction have been used to determine the physical and chemical properties of uranium contamination in soils from the Fernald Environmental Management Project in Ohio. The information gained from these studies has been used in the development and testing of remediation technologies.
Date: March 1995
Creator: Buck, E. C.; Brown, N. R. & Dietz, N. L.
Item Type: Refine your search to only Report
open access

Analytical Electron Microscopy Characterization of Uranium-Contaminated Soils from the Fernald Site, FY1993 Report

Description: A combination of optical microscopy, scanning electron microscopy with backscattered electron detection (SEM/BSE), and analytical electron microscopy (AEM) is being used to determine the nature of uranium in soils from the Fernald Environmental Management Project. The information gained from these studies is being used to develop and test remediation technologies. Investigations using SEM have shown that uranium is contained within particles that are typically 1 to 100 micrometers in diameter. … more
Date: October 1994
Creator: Buck, E. C.; Cunnane, J. C.; Brown, N. R. & Dietz, N. L.
Item Type: Refine your search to only Report
open access

A Tutorial on the Construction of High-Performance Resolution/Paramodulation Systems

Description: Over the past 25 years, researchers have written numerous deduction systems based on resolution and paramodulation. Of these systems, a very few have been capable of generating and maintaining a formula database "containing more than just a few thousand clauses. These few systems were used to explore mechanisms for rapidly extracting limited subsets of relevant" clauses. We have written this tutorial to reflect some of the best ideas that have emerged and to cast them in a form that makes them … more
Date: September 1990
Creator: Butler, R. & Overbeek, R.
Item Type: Refine your search to only Report
open access

Chaotic Dynamics of Loosely Supported Tubes in Crossflow

Description: By means of the unsteady-flow theory and a bilinear mathematical model, a theoretical study was conducted of the chaotic dynamics associated with the fluid-elastic instability of loosely supported tubes. Calculations were performed for the RMS of tube displacement, bifurcation diagram, phase portrait, power spectral density, and Poincare map. Analytical results show the existence of chaotic, quasi-periodic, and periodic regions when flow velocity exceeds a threshold value.
Date: July 1991
Creator: Cai, Y. & Chen, Shoei-Sheng
Item Type: Refine your search to only Report
open access

Chaotic Vibrations of Nonlinearly Supported Tubes in Crossflow

Description: By means of the unsteady-flow theory and a bilinear mathematical model, a theoretical study is presented for chaotic vibrations associated with the fluid-elastic instability of nonlinearly supported tubes in a crossflow. Effective tools, including phase portraits, power spectral density, Poincare maps, Lyapunov exponent, fractal dimension, and bifurcation diagrams, are utilized to distinguish periodic and chaotic motions when the tubes vibrate in the instability region. The results show periodi… more
Date: February 1992
Creator: Cai, Y. & Chen, Shoei-Sheng
Item Type: Refine your search to only Report
open access

Nonlinear Dynamics of a Stack/Cable System

Description: In this study, we developed a coupled model of wind-induced vibration of a stack, based on an unsteady-flow theory and nonlinear dynamics of the stack's heavy elastic suspended cables. Numerical analysis was performed to identify excitation mechanisms. The stack was found to be excited by vortex shedding. Once lock-in resonance occurred, the cables were excited by the transverse motion of the stack. Large-amplitude oscillations of the cables were due to parametric resonance. Appropriate techniq… more
Date: July 1995
Creator: Cai, Y. & Chen, Shoei-Sheng
Item Type: Refine your search to only Report
open access

A Review of Dynamic Characteristics of Magnetically Levitated Vehicle Systems

Description: The dynamic response of magnetically levitated (maglev) ground transportation systems has important consequences for safety and ride quality, guideway design, and system costs. Ride quality is determined by vehicle response and by environmental factors such as humidity and noise. The dynamic response of the vehicles is the key element in determining ride quality, while vehicle stability is an important safety-related element. To design a guideway that provides acceptable ride quality in the sta… more
Date: November 1995
Creator: Cai, Y. & Chen, Shoei-Sheng
Item Type: Refine your search to only Report
open access

A Theory for Fluidelastic Instability of Tube-Support-Plate Inactive Modes

Description: Fluid-elastic instability of loosely supported tubes, vibrating in a tube-support-plate (TSP) inactive mode, is suspected to be one of the main causes of tube failure in some operating steam generators and heat exchangers. This report presents a mathematical model for fluid-elastic instability of loosely supported tubes exposed to non-uniform cross-flow. The model incorporates all motion-dependent fluid forces based on the unsteady flow theory. In the unstable region associated with a TSP-inact… more
Date: September 1990
Creator: Cai, Y.; Chen, Shoei-Sheng & Chandra, S.
Item Type: Refine your search to only Report
open access

Dynamics and Controls in Maglev Systems

Description: The dynamic response of magnetically levitated (maglev) ground transportation systems has important consequences for safety and ride quality, guideway design, and system costs. Ride quality is determined by vehicle response and by environmental factors such as humidity and noise. The dynamic response of the vehicles is the key element in determining ride quality, and vehicle stability is an important safety-related element. To design a proper guideway that provides acceptable ride quality in th… more
Date: September 1992
Creator: Cai, Y.; Chen, Shoei-Sheng & Rote, D. M.
Item Type: Refine your search to only Report
open access

Vehicle/Guideway Interaction in Maglev Systems

Description: Dynamic interactions between the vehicle and guideway in a high-speed ground transportation system based on magnetically levitated (maglev) vehicles were studied, with an emphasis on the effects of vehicle and guideway parameters. Two dynamic models for the vehicle are presented. In one model, the vehicle is considered to be a moving force traveling at various speeds on a simply supported single- or two-span beam. In the second model, the vehicle is considered to be one-dimensional and has two … more
Date: March 1992
Creator: Cai, Y.; Chen, Shoei-Sheng & Rote, D. M.
Item Type: Refine your search to only Report
open access

Dynamic Stability of Maglev Systems

Description: Because dynamic instability is not acceptable for any commercial maglev systems, it is important to consider this phenomenon in the development of all maglev systems. This study considers the stability of maglev systems based on experimental data, scoping calculations, and simple mathematical models. Divergence and flutter are obtained for coupled vibration of a three-degree-of-freedom maglev vehicle on a guideway consisting of double L-shaped aluminum segments attached to a rotating wheel. The… more
Date: April 1992
Creator: Cai, Y.; Chen, Shoei-Sheng; Mulcahy, T. M. & Rote, D. M.
Item Type: Refine your search to only Report
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