| A Fluidic Dump Combustor for Ramjet Engines |
Dec-2009 |
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| Authors:
David J Forliti; STATE UNIV OF NEW YORK AT BUFFALO AMHERST RESEARCH FOUNDATION
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 | Flame stabilization is the act of maintaining combustion in the presence of a high-speed premixed flow, and continues to be an important process that influences the performance and limitations for propulsion applications. A common approach for current generation flame holders involves the employment of a low-speed recirculation zone where hot combustion products are maintained and act as a continuous ignition source. The recirculation zone is often induced using a wake-generating ... |
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| On the Impact of Injection Schemes on Transition in Hypersonic Boundary Layers |
13-Oct-2009 |
12 pages |
| Authors:
Ivett A Leyva; Stuart Laurence; Hans G Hornung; Joseph S Jewell; Joe Shepherd; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
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 | Three geometries are explored for injecting CO2 into the boundary layer of a sharp five degree half-angle cone. The impact of the injection geometry, namely discrete injection holes or a porous conical section, on tripping the boundary layer is examined, both with and without injected flow. The experiments are conducted at Caltech's T5 reflected shock tunnel. Two different air free-stream conditions are explored. For the discrete-hole injectors, the diameter for ... |
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| Numerical Model Study of the Tuscarawas River below Dover Dam, Ohio |
Sep-2009 |
58 pages |
| Authors:
Richard L Stockstill; Jane M Vaughan; ENGINEER RESEARCH AND DEVELOPMENT CENTER VICKSBURG MS COASTAL AND HYDRAULICS LAB
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| The U.S. Army Corps of Engineers, Huntington District (LRH) has been charged with upgrading Dover Dam to meet hydrologic design standards and address stability issues. The LRH requested that the U. S. Army Engineer Research and Development Center, Coastal and Hydraulics Laboratory (CHL), evaluate the flow conditions in the Tuscarawas River downstream of Dover Dam as part of a safety assurance program. The two-dimensional depth-averaged module of the Adaptive Hydraulics ... |
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| Collecting, Retrieving and Analyzing Knowledge Value Added (KVA) Data From U.S. Navy Vessels Afloat |
Sep-2009 |
82 pages |
| Authors:
Jason B Homer; NAVAL POSTGRADUATE SCHOOL MONTEREY CA DEPT OF INFORMATION SCIENCES
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| Program managers throughout the Department of Defense (DoD) are faced with technology portfolio management problems. Critical to these efforts is the need to track the performance of the technology on a routine, ongoing basis. This thesis focuses on solving this general problem in the specific context of the United States Navy's Cryptologic Carry-On Program (CCOP). This study provides a method that can gather real world data from United States Naval ... |
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| Environmental Assessment (EA): Proposed Security Facilities, Little Mountain Test Annex, Utah |
09-Jul-2009 |
63 pages |
| Authors:
Randal Klein; Kay Winn; STREAMLINE CONSULTING LLC FARMINGTON UT
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| Hill Air Force Base (AFB) proposes to construct security facilities to protect Little Mountain Test Annex (LMTA) from unauthorized access and enable guards to intercept contraband (weapons, explosives, drugs, classified materials, etc.) while maximizing vehicular traffic flow. The findings of this EA indicate that the proposed action would not have significant adverse effects on the human environment or any of the environmental resources as described in the EA. Therefore, it ... |
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| An Ocean Sensor Array to Detect Small-Scale Variability |
Jul-2009 |
5 pages |
| Authors:
Janet Sprintall; SCRIPPS INSTITUTION OF OCEANOGRAPHY LA JOLLA CA
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| The specific objectives of this DURIP project were to provide direct measurements of velocity and currents in narrow straits with shallow sill depths in order to: (1) Examine the relative roles of the tidal and longer timescale flows in the generation and evolution of the small-scale dynamical flow features in straits; (2) Determine how the small-scale features evolve with observed across- and along-strait variation in sea level and the corresponding ... |
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| The Effect of Variable Gravity on the Cooling Performance of a Partially-Confined FC-72 Spray |
Jul-2009 |
214 pages |
| Authors:
John McQuillen; Travis E Michalak; Kirk L Yerkes; Scott K Thomas; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH PROPULSION DIRECTORATE
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| This thesis discusses the effects of a variable-gravity environment on the performance of a subcooled partially-confined spray. An experiment, consisting of a test chamber, the associated flow loops, and instrumentation, was fabricated and flown on the NASA Reduced-Gravity Testing Platform. This modified KC-135 aircraft followed a parabolic flight path to provide various acceleration levels. The spray chamber contained two opposing nozzles spraying onto Thick Film Resistor (TFR) heaters, which were ... |
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| Accuracy Analysis for Kinetic Modeling of Homogeneous Condensation in Plumes |
Jun-2009 |
6 pages |
| Authors:
Sergey Gimelshein; Deborah Levin; Ingrid Wysong; Ryan Jansen; Michael Zeifman; Zheng Li; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
|
| Two different approaches for modeling the clustering in rapidly expanding plumes have been reported in the literature. The first approach, known as the classical approach, takes its starting point from the classical nucleation theory (CNT) which is based on equilibrium thermodynamics. The second one, known as the kinetic approach, treats nucleation as the process of kinetic chemical aggregation. The first, macroscopic, approach, while being useful and found to be applicable ... |
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| Implicit and P-Multi-Grid Algorithms for High-Order Spectral Difference Method on Unstructured Grids |
May-2009 |
6 pages |
| Authors:
Z J Wang; IOWA STATE UNIV AMES DEPT OF AEROSPACE ENGINEERING
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| The development of high-order methods (order of accuracy 2nd order) on unstructured grids is widely viewed as a major pacing item in computational fluid dynamics (CFD). Efficient high-order methods capable of handling complex geometries are required to compute vortex dominated flows, and to perform large eddy simulation and direct numerical simulation with complex configurations, and to predict aeroacoustic noise generation and propagation. The primary objective of the present research is ... |
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| Innovative Microsystems: Novel Nanostructures to Capture Circulating Breast Cancer Cells |
May-2009 |
45 pages |
| Authors:
Yitshak Zohar; James C Baygents; Roberto Guzman; Ronald L Heimark; Joyce A Schroeder; ARIZONA UNIV TUCSON
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| The goal of this project is to develop a microsystem for sorting metastatic breast cancer cells from a heterogeneous suspension of cells circulating in the blood stream. Conceptually, the technique requires the transformation of a distinguishing biochemical characteristic of the target cells, such as up-regulated cadherin phenotype, into a mechanical or electrical that makes it possible to selectively manipulate the cells on the microscale. The project includes developments of a ... |
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| Anisotropy of the Hot Plastic Deformation of Ti-6Al-4V Single-Colony Samples (Preprint) |
Apr-2009 |
26 pages |
| Authors:
S L Semiatin; A A Salem; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH MATERIALS AND MANUFACTURING DIRECTORATE
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| The critical resolved shear stresses and flow curves for the seven possible slip systems in Ti-6Al-4V with a lamellar microstructure were determined via high temperature uniaxial compression testing. For this purpose, samples with a rectangular cross section were cut from single colonies grown using a float-zone technique and then tested at 815 degrees C. Each sample was oriented for single slip along one of seven different slip systems in the ... |
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| Decisive Routing and Admission Control According to Quality of Service Constraints |
Mar-2009 |
110 pages |
| Authors:
Cindy C Reese; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH GRADUATE SCHOOL OF ENGINEERING AND MANAGEMENT
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| This thesis will research, model, and propose options to enhance command and control in for communication networks. My goal is to research the viability of combing past research in the areas of network prediction, context-aware routing, and QoSbased routing optimization in order to create an intelligent routing protocol platform for mobile networks. It will consolidate efforts from an Intelligent Agent Based Framework to Maximize Information Utility by Captain John Pecarina, ... |
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| Adaptive Selections of Sample Size and Solver Iterations in Stochastic Optimization with Application to Nonlinear Commodity Flow Problems |
Mar-2009 |
57 pages |
| Authors:
David A Vondrak; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
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| We present an algorithm to approximately solve certain stochastic nonlinear programs through sample average approximations. The sample sizes in these approximations are selected by approximately solving optimal control problems defined on a discrete-time dynamic system. The optimal-control problem seeks to minimize the computational effort required to reach a near-optimal objective value of the stochastic nonlinear program. Unknown control-problem parameters such as rate of convergence, computational effort per solver iteration, and ... |
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| Polymer Drag Reduction and Bioluminescence Reduction |
Mar-2009 |
9 pages |
| Authors:
Michael I Latz; CALIFORNIA UNIV REGENTS SAN DIEGO LA JOLLA CA
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| Drag reducing polymers interfere with the bursting process in turbulence by absorbing the energy like a shock absorber. The objective of this project was to test the effect of the polymer drag reducing agent polyethylene oxide (PEO) on bioluminescence stimulation in fully-characterized pipe flow. The well-documented reduction of turbulent skin friction by PEO was hypothesized to also result in a similar reduction of flow-stimulated bioluminescence. Drag reduction and bioluminescence suppression ... |
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| Eddy-Mean Flow Interactions in Western Boundary Current Jets |
Feb-2009 |
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| Authors:
Stephanie N Waterman; WOODS HOLE OCEANOGRAPHIC INSTITUTION MA
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| This thesis examines eddy-mean flow interactions in western boundary current jets via theoretical studies of eddy-mean flow interactions in idealized configurations and an observational analysis to characterize eddy-mean flow interactions in the Kuroshio Extension. Theoretical studies are made of the mechanism by which eddies drive recirculation gyres through nonlinear rectification, and the role that eddies play in the downstream evolution of a baroclinic jet subject to mixed instabilities. The observational ... |
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| Equivalent Roughness Height for Plane Bed Under Oscillatory Flow |
Jan-2009 |
15 pages |
| Authors:
Magnus Larson; Benoit Camenen; Atilla Bayram; CEMAGREF LYON (FRANCE)
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| A new relationship between the roughness height and the main hydrodynamic and sediment parameters for plane beds under oscillatory conditions is presented. In order to derive such a relationship, a large data base encompassing plane-bed experiments was compiled from previous investigations and analyzed. Different methods to estimate the roughness height were investigated. Comparisons between the data and different existing predictive formulas for the bed roughness obtained from the literature were ... |
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| Recent Progress in Silicon Mems Oscillators |
01-Dec-2008 |
13 pages |
| Authors:
Wan-Thai Hsu; DISCERA INC ANN ARBOR MI
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| This paper first reviews key milestones in the making of silicon MEMS oscillators and how MEMS resonators can be used as frequency references for electronic systems, starting from silicon resonators device designs with different fabrication processes, to wafer level packaging technologies, to the robustness of volume manufacturing processes. Secondly, as final products, various MEMS oscillators from various companies are compared with quartz crystal oscillators in terms of jitter, power consumption, ... |
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| Information Communication Technology, State building, and Globalization in the 21st Century: Regional Frameworks for Emerging State Assistance |
Dec-2008 |
93 pages |
| Authors:
Justin Y Reese; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
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| The U.S.-led effort to form transnational institutions and processes contributes to the decreasing relevance of the nation-state in relation to what has become known as globalization. Globalization has modified the essential role of the nation-state towards managing global flows of resource, capital, and populations rather than, as in the past, presiding over distinct national economies. The relationship between ICT and political stability is explored in order to determine the existence ... |
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| Evaluation of the Snap Sampler for Sampling Ground Water Monitoring Wells for Inorganic Analytes |
Dec-2008 |
74 pages |
| Authors:
Louise V Parker; Nathan D Mulherin; Gordon E Gooch; ENGINEER RESEARCH AND DEVELOPMENT CENTER HANOVER NH COLD REGIONS RESEARCH AND ENGINEERING LAB
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| Abstract: Laboratory studies and a field demonstration were conducted to determine the ability of the Snap Sampler to recover representative concentrations of inorganic analytes, including metals, from ground water. For the laboratory studies, concentrations of analytes in Snap Sampler samples were compared with concentrations of the analytes in samples collected from a standpipe (i.e., control samples). These studies clearly demonstrated that Snap Sampler concentrations were comparable to control sample concentrations. ... |
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| A Metadata Calculus for Securing Information Flows |
Dec-2008 |
8 pages |
| Authors:
Mudhakar Srivatsa; Dakshi Agrawal; Shane Balfe; IBM THOMAS J WATSON RESEARCH CENTER YORKTOWN HEIGHTS NY
|
| Traditional approaches to information sharing use a highly conservative approach to deduce the metadata for an output object x derived from input objects y(sub 1), y(sub 2), ... , y(sub n) [e.g.: maximum over the security labels of all input objects]. Such approaches does not account for functions that explicitly down- grade the value of an object. Consequently, the security labels in traditional approaches tend to monotonically increase as newer ... |
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| DNS and RANS Simulation of Dispersion Downstream of an Obstacle |
Dec-2008 |
9 pages |
| Authors:
Gianluca Iaccarino; Riccardo Rossi; BOLOGNA UNIV (ITALY)
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| Dispersion in the wake of an obstacle is studied as a step towards the analysis of bio-agent release in urban environments. Available experimental measurements are used to compare in details numerical predictions obtained using Reynolds-Averaged Navier-Stokes (RANS) techniques and Direct Numerical Simulations (DNS). In particular, turbulent scalar fluxes are compared to assess the quality of simple closure based on eddy diffusivity assumptions. The results obtained using different RANS closures show ... |
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| System-Wide Water Resources Program Nutrient Sub-Model (SWWRP-NSM) Version 1.1 |
01-Sep-2008 |
55 pages |
| Authors:
Zhonglong Zhang; Billy E Johnson; Terry K Gerald; ENGINEER RESEARCH AND DEVELOPMENT CENTER VICKSBURG MS ENVIRONMENTAL LAB
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| This report discusses major developments that have occurred since the release of NSM Version 1.0. These improvements were in the areas of: 1) partitioning of nutrients (dissolved and adsorbed) within surface runoff, 2) mass transfer of nutrients between the soils and overlying water column, 3) erosion and sedimentation of particulate nutrients, and 4) soil plant dynamics. Nutrients at or near the soil surface can be transformed to overland flow in ... |
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| Pylon Effects on a Scramjet Cavity Flameholder Flowfield |
01-Sep-2008 |
204 pages |
| Authors:
Andrew B Freeborn; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH GRADUATE SCHOOL OF ENGINEERING AND MANAGEMENT
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| Cavity flameholders in supersonic combustion ramjet (scramjet) combustors, while effective, fail to take advantage of the full combustor volume. Adding a pylon to the leading edge of a cavity flameholder generates a flowfield increasing mass exchange between the cavity and main combustor flow, increasing the mixing interface between flameholder products and main combustor flow, and exhibiting minimal Reynolds number effects. To demonstrate this modified flowfield driven by supersonic expansion behind ... |
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| Operation Iraqi Freedom: Actions Needed to Enhance DOD Planning for Reposturing of U.S. Forces from Iraq |
01-Sep-2008 |
86 pages |
| Authors:
Cheryl Weissman; Tristan T To; John J Marzullo; Guy A Lofaro; David A Schmitt; William M Solis; Katherine Lenane; John Lee; Gregory Marchand; Christopher Turner; GOVERNMENT ACCOUNTABILITY OFFICE WASHINGTON DC
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| While the pace and overall extent of reposturing in Iraq has yet to be determined, various defense commands began planning for reposturing in fall 2007, and in May 2008 DOD began coordinating these individual planning efforts to develop a logistical framework based on three key assumptions. According to DOD officials, initial planning efforts were uncoordinated because the three organizations undertaking them the Defense Logistics Agency (DLA), the Army Materiel Command(AMC), ... |
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| Optimal Jammer Placement to Interdict Wireless Network Services |
01-Jun-2008 |
59 pages |
| Authors:
Arun Shankar; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
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| The demand for wireless networks continues to grow as the need for portable, low-cost telecommunications systems increases around the world. Wireless networks are particularly complex because their topologies can change in response to operational requirements or environmental conditions and also because wireless networks are susceptible to electromagnetic interference. In this thesis, we consider the challenges associated with the operation and jamming of so-called wireless mesh networks. In a wireless mesh ... |
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| Application of a New Grain-Based Reconstruction Algorithm to Microtomography Images for Quantitative Characterization and Flow Modeling |
Jun-2008 |
14 pages |
| Authors:
Stephanie Nyman; Karsten E Thompson; Allen H Reed; Clinton S Willson; Christopher D White; Janok P Bhattacharya; NAVAL RESEARCH LAB STENNIS SPACE CENTER MS MARINE GEOACOUSTICS DIV
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| X-ray computed microtomography (XMT) is used for high-resolution, nondestructive imaging and has been applied successfully to geologic media. Despite the potential of XMT to aid in formation evaluation, currently it is used mostly as a research tool. One factor preventing more widespread application of XMT technology is limited accessibility to microtomography beamlines. Another factor is that computational tools for quantitative image analysis have not kept pace with the imaging technology ... |
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| Innovative Microsystems: Novel Nanostructures to Capture Circulating Breast Cancer Cells |
01-May-2008 |
23 pages |
| Authors:
Yitshak Zohar; ARIZONA UNIV TUCSON
|
| The goal of this project is to develop a microsystem for sorting metastatic breast cancer cells from a heterogeneous suspension of cells circulating in the blood stream. Conceptually, the technique requires the transformation of a distinguishing biochemical characteristic of the target cells, such as up-regulated cadherin phenotype, into a mechanical or electrical that makes it possible to selectively manipulate the cells on the microscale. The project includes developments of a ... |
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| White Sands Missile Range 2007 Urban Study: Data Processing - Volume DP-3 (Airflow Qualitative Assessment) |
MAY 2008 |
|
| Authors:
Gail Vaucher; Manuel Bustillos; ARMY RESEARCH LAB WHITE SANDS MISSILE RANGE NM COMPUTATIONAL AND INFORMATION SCIENCE DIRECTORATE
|
| Urban toxic chemical releases pose a threat to the military and civilians. The White Sands Missile Range (WSMR) Urban Studies address two critical elements in diagnosing airborne hazard releases, namely, airflow (chemical distribution) and stability (chemical concentration). This document provides a qualitative assessment of seven airflow features targeted by the WSMR 2007 Urban Study (W07US). The W07US stability assessment is published separately. The features identified for verification and characterization include ... |
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| Estimation of Combined Wave and Storm Surge Overtopping at Earthen Levees |
MAY 2008 |
17 pages |
| Authors:
Steven A. Hughes; ENGINEER RESEARCH AND DEVELOPMENT CENTER VICKSBURG MS COASTAL AND HYDRAULICS LAB
|
| This Coastal and Hydraulics Engineering Technical Note (CHETN) provides empirical equations for estimating several parameters of unsteady flow resulting from the combination of steady storm surge overflow and overtopping of irregular waves at a trapezoidal-shaped earthen levee. Equations are given for the average overtopping discharge and the cumulative probability distribution of instantaneous overtopping discharge. On the landward-side slope, empirical equations can be used to estimate the mean flow depth, mean ... |
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| Multiscale Modeling and Computation of Liquid Crystal Polymers, Polymer Blends, and Polymer Nanocomposites: Investigation of Rheology and Material Properties |
15 APR 2008 |
11 pages |
| Authors:
Qi Wang; FLORIDA STATE UNIV TALLAHASSEE DEPT OF MATHEMATICS
|
| High-performance polymeric materials such as liquid crystal polymers and polymer nano-particle composites have many military applications. The project aimed to study the mesoscopic structure formation during flow processing and characterization of material properties in solid states. Significant progress has been made to model the materials and to understand their rheological properties in melt or solution processing. Electrical and thermal conduction properties of the nanocomposites are characterized by the low volume ... |
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| Building the Holocene Clinothem in the Gulf of Papua: An Ocean Circulation Study |
28 MAR 2008 |
18 pages |
| Authors:
Rudy Slingerland; Robert W. Selover; Andrea S. Ogston; Timothy R. Keen; Neal W. Driscoll; John D. Milliman; NAVAL RESEARCH LAB STENNIS SPACE CENTER MS OCEANOGRAPHY DIV
|
| This paper investigated the role that tidal and wind-driven flows and buoyant river plumes play in the development of the Holocene clinothem in the Gulf of Papua. Time series data from bottom tripods and a mooring were obtained at four locations near the mouth of the Fly River during portions of 2003 and 2004. Flows in the Gulf of Papua during calendar year 2003 were hindcast every 3 h using ... |
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| Human System Integration Support Tools with Links to DoD System Acquisition Phases |
01-Mar-2008 |
|
| Authors:
Lila Laux; Ronald L Small; Susan G Archer; Edward A Martin; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH HUMAN EFFECTIVENESS DIRECTORATE
|
| This report is designed to help proceduralize the human-systems integration (HSI) process by linking the flow of HSI analyses in the systems acquisition process to tools that can support those analyses. The initial sections of this report describe how this report is intended to be used, define acquisition-process and HSI terminology, and provide some HSI metrics. All HSI domains are explicitly addressed with the exception of habitability. Techniques for confirming ... |
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| An Attacker-Defender Model for IP-Based Networks |
01-Mar-2008 |
79 pages |
| Authors:
Timothy R Barkley; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| The Internet Protocol (IP) has emerged as the dominant technology for determining how data is routed across the Internet. Because IP flows are defined essentially in terms of origin-destination (O-D) pairs, we represent IP traffic engineering as a multi-commodity flow problem in which each O-D pair is treated as a separate commodity. We account for the diversity in IP routing by modeling opposite extremes of traffic engineering: naive traffic engineering ... |
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| Molecular Characterization of Wetland Soil Bacterial Communities in Constructed Mesocosms |
MAR 2008 |
139 pages |
| Authors:
Elisabeth M. Leon; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH GRADUATE SCHOOL OF ENGINEERING AND MANAGEMENT
|
| 16S rRNA gene analysis was performed on soil samples from a subsurface flow mesosocm experiment, mimicking a constructed wetland. Three typical wetland species of plant were used in nine of the columns and three columns were unplanted controls. Analyses showed that plant presence, plant species, and depth did not have a significant effect on microbial community composition. However, richness analyses illustrated that plant presence had a positive effect on richness, ... |
|
| Ferroelectric Plasma Thruster |
29 FEB 2008 |
10 pages |
| Authors:
Scott D. Kovaleski; Mark A. Kemp; MISSOURI UNIV-COLUMBIA
|
| The Ferroelectric Plasma Thruster (FEPT) has been developed as an electrostatic micropropulsion thruster for the smallest classes of spacecraft. The FEPT consists of a thin wafer of lithium niobate ferroelectric material, with a solid electrode on one side, and an electrode with an aperture on the other. When radiofrequency high voltage is applied between the electrodes, through the thickness of the crystal, a combination of triple point and piezoelectric effects ... |
|
| Ice Considerations in the Design of River Restoration Structures |
01-Feb-2008 |
35 pages |
| Authors:
Andrew M Tuthill; ENGINEER RESEARCH AND DEVELOPMENT CENTER HANOVER NH COLD REGIONS RESEARCH AND ENGINEERING LAB
|
| Modern river restoration and streambank stabilization projects constructed of natural materials are gaining favor over traditional materials such as riprap and concrete. These new structure types provide a more aesthetic and lower-cost means of controlling bed and bank erosion, while improving flow diversity and habitat. Little design guidance exists for these structures on ice-affected rivers, however. This report provides basic design guidelines for these in-stream structures in the ice environment. ... |
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| Estimation of Overtopping Flow Velocities on Earthen Levees Due to Irregular Waves |
JAN 2008 |
19 pages |
| Authors:
Steven A. Hughes; ENGINEER RESEARCH AND DEVELOPMENT CENTER VICKSBURG MS COASTAL AND HYDRAULICS LAB
|
| This Coastal and Hydraulics Engineering Technical Note (CHETN) provides empirical equations to estimate flow velocity and flow thickness resulting from irregular waves overtopping a trapezoidal-shaped earthen levee. The CHETN summarizes published European research with the goal of providing practicing engineers with design guidance in a concise and understandable form. Worked examples illustrate application of the empirical equations. |
|
| Reconfigurable Computing: Experiences and Methodologies |
JAN 2008 |
34 pages |
| Authors:
Song-Jun Park; Dale Shires; Brian Henz; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD COMPUTATIONAL AND INFORMATION SCIENCES DIR
|
| Reconfigurable computing refers to computations done with flexible fabrics where the data path and control flow can be customized to the application. Unlike traditional computing using the fetch, execute, and store model that is highly sequential, reconfigurable computing allows developers to program their applications both spatially and temporally. This allows for potentially great speed-ups with applications that might be well-suited for such approaches. However, programming in this style requires specialized ... |
|
| High Reynolds Number Micro-Bubble and Polymer Drag Reduction Experiments |
JAN 2008 |
183 pages |
| Authors:
Steven L. Ceccio; David R. Dowling; Marc Perlin; Michael Solomon; MICHIGAN UNIV ANN ARBOR DEPT OF MECHANICAL ENGINEERING
|
| This effort was a continuation of the joint ONR and DARPA programs of the PI and Co-PI's, initiated as part of the DARPA Friction Drag Reduction Program (ATO/TTO). The purpose of the investigation was to examine the physics and engineering of friction drag reduction methods for turbulent boundary layers (TBL) found in hydrodynamic flows. Three methods of friction drag reduction (FDR) were examined: * Polymer Drag Reduction * Micro-bubble Drag ... |
|
| Assessing Plankton and Particles with an Autonomous Imaging LOPC |
Jan-2008 |
6 pages |
| Authors:
Checkley; David M Jr; Alex W Herman; SCRIPPS INST OF OCEANOGRAPHY LA JOLLA CA INTEGRATIVE OCEANOGRAPHY DIV
|
| We wish to characterize and quantify particles and plankton in the pelagic ocean, to enable an understanding of their dynamics and their roles in ecosystems and biogeochemical cycles. Characterization and quantification are also necessary to describe the distribution and abundance of particles and plankton in the sea in relation to the environment, including its acoustic and optical properties. Our objective is to integrate the Laser Optical Plankton Counter (LOPC) with ... |
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| Analysis of Different Approaches to Modeling of the Nozzle Flows in the Near Continuum Regime (Preprint) |
21 DEC 2007 |
25 pages |
| Authors:
E. V. Titov; D. A. Levin; N. E. Gimelshein; S. F. Gimelshein; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
|
| A conical nozzle flow is studied for Reynolds numbers 1,230 and 12,300 using different numerical techniques: the direct simulation Monte Carlo method, the solution of Navier-Stokes equations that accounts for wall temperature jump and velocity slip, and statistical and deterministic approaches for the BGK equation. Detailed comparison of the efficiency, stability, accuracy, and convergence of the employed numerical techniques provides better understanding of their benefits and deficiencies, and assists in ... |
|
| Hydraulic Tomography and High-Resolution Slug Testing to Determine Hydraulic Conductivity Distributions - Year 3 |
DEC 2007 |
58 pages |
| Authors:
Carl D. McElwee; Rick Devlin; Brian Wachter; KANSAS UNIV LAWRENCE DEPT OF GEOLOGY
|
| A typical method used to determine fluid behavior in a geologic matrix near a well is a pumping test Here a pump is installed into a well and groundwater is removed or injected while water levels in surrounding observation wells are monitored. Then the aquifer parameters can be estimated by monitoring changes in water levels at observation wells at some distance These types of tests are typically large in scale, ... |
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| Acoustic Doppler Current Profiler (ADCP) Velocity Verification Experiments in the Navy's Large Cavitation Channel (LCC) |
DEC 2007 |
38 pages |
| Authors:
Dylan A. Chirchella; NAVAL SURFACE WARFARE CENTER CARDEROCK DIV BETHESDA MD
|
| The Resistance and Powering Division (Code 5200) of The Naval Surface Warfare Center, Carderock Division (NSWCCD) conducted verification experiments on a 20 degree Acoustic Doppler Current Profiler (ADCP) unit produced by RD Instruments (RDI) of San Diego, California. These experiments were conducted in the Navy's Large Cavitation Channel (LCC) located in Memphis, Tennessee. Although they have many other possible future uses, currently the ADCP units tested during this series are ... |
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| Influence of Surface Roughness on Polymer Drag Reduction |
30 NOV 2007 |
25 pages |
| Authors:
Steven L. Ceccio; David R. Dowling; Marc Perlin; Michael Solomon; MICHIGAN UNIV ANN ARBOR DEPT OF MECHANICAL ENGINEERING
|
| This effort accompanied the DARPA Friction Drag Reduction Program (ATO/TTO) effort at the University of Michigan funded under contract HR-0011-04-1-001 "High Reynolds Number Micro-bubble and Polymer Drag Reduction Experiments" for flows over smooth surfaces. The details of that effort can be found in the final technical report for that project. The purpose of the additional investigation was to examine the physics and engineering of friction drag reduction methods for turbulent ... |
|
| Magneto-Fluid Dynamics Calculations for Aerodynamics |
20 NOV 2007 |
35 pages |
| Authors:
Robert W. MacCormack; STANFORD UNIV CA DEPT OF AERONAUTICS AND ASTRONAUTICS
|
| Magneto-Hydro-Dynamics (MHD) or more generally Magneto-Fluid-Dynamics (MFD) offers a potential breakthrough in both hypersonic vehicle design and propulsion. Reductions in both drag and heat transfer and flow control using magnetic fields can be important for enabling a hypersonic vehicle to pass more efficiently and safely through the atmosphere. Magnetic and electric fields placed within the propulsion system may enable the extraction of electrical energy from the ionized flow entering the ... |
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| Locally Conservative, Stabilized Finite Element Methods for Variably Saturated Flow |
06 NOV 2007 |
45 pages |
| Authors:
C. E. Kees; M. W. Farthing; C. N. Dawson; ENGINEER RESEARCH AND DEVELOPMENT CENTER VICKSBURG MS COASTAL AND HYDRAULICS LAB
|
| Standard Galerkin finite element methods for variably saturated groundwater flow have several deficiencies. For instance, local oscillations can appear around sharp infiltration fronts without the use of mass-lumping, and velocity fields obtained from differentiation of pressure fields are discontinuous at element boundaries. Here, we consider conforming finite element discretizations based on a multiscale formulation along with recently developed, local postprocessing schemes. The resulting approach maintains the basic flexibility and appeal ... |
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| Towards Fieldable Rapid Bioagent Detection: advanced Resonant Optical Waveguide and Biolayer Structures for Integrated Biosensing |
NOV 2007 |
23 pages |
| Authors:
Lawrence A. Hornak; Dimitris Korakakis; Aaron Timperman; WEST VIRGINIA UNIV RESEARCH CORP MORGANTOWN
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| This research project established the understanding necessary for the stacked planar affinity-regulated resonate optical waveguide (SPARROW) architecture to serve as a transducer device platform for rapid biomolecular detection. SPARROW structures have been grown with waveguide losses of less than 1 dB/cm. Thin biolayers of less than 10 nm were achieved and SAM attachment to polycrystalline surfaces studied. SPARROW transducer measurements were conducted using sucrose analyte solutions applied to the top ... |
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| A CFD Study of the Aerodynamics of a 6x6x8 Foot Cargo Container Suspended Beneath a Helicopter. Part 1: Aerodynamics of the Stationary Container |
OCT 2007 |
78 pages |
| Authors:
Johannes N. Theron; Earl P. Duque; Luigi Cicolani; NORTHERN ARIZONA UNIV FLAGSTAFF
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| This report is the first of several on a study of the unsteady aerodynamics of the CONEX cargo container This work is in support of an effort to develop a model of the CONEX unsteady aerodynamics for use in simulations of helicopter-slung-load dynamics It is known from the literature on cargo container aerodynamics that instability is caused by unsteady flow effects such as vortex shedding and flow structure lags and ... |
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| Axial Waterjet (AxWJ) Model 5662: Hull Resistance and Model-Scale Powering with LDV Nozzle Design |
SEP 2007 |
72 pages |
| Authors:
Dominic S. Cusanelli; Scott A. Carpenter; NAVAL SURFACE WARFARE CENTER CARDEROCK DIV BETHESDA MD
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| This report is a partial documentation of the first series of model-scale tests conducted 12/06-2/07, to evaluate the Axial Waterjet (AxWJ), Model 5662, on the Joint High Speed Sealift (JHSS) hull platform. This document contains calm water resistance and model-scale powering test results only. Bare hull effective powers were determined for the AxWJ hull at three displacement conditions. Appended effective power was determined for the AxWJ hull with the LDV ... |
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| An Analysis of IEEE 802.16 and WiMAX Multicast Delivery |
SEP 2007 |
99 pages |
| Authors:
Patrick A. Staub; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
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| Broadband and wireless have enjoyed a massive mass market adoption in the past twenty years. Users want to be able to enjoy all applications, including multimedia, voice, and data, while still being able to access them in a mobile and fixed environment. Multicasting is a tool used in networking which allows for transmitting information to a select group of users and is especially useful for time-sensitive data which can be ... |
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