| An Analysis of the Effect of Knowledge Management on the Execution of Simplified Acquisition Procedures |
27 Dec 2012 |
76 pages |
| Authors:
Jon D Barnes; Hugh J Williams; NAVAL POSTGRADUATE SCHOOL MONTEREY CA GRADUATE SCHOOL OF BUSINESS AND PUBLIC POLICY
|
 | Simplified acquisition procedures (SAPs) are a fundamental and ubiquitous component of federal contracting and are executed by acquisition professionals at all levels of government. Because of their relative simplicity, procurements using SAPs are often left to less experienced personnel who are in the inchoate stages of developing their skills and knowledge. Knowledge management represents the effective organization, dissemination, and utilization of an enterprise's knowledge resources. When designed and executed with ... |
|
| Close Air Support versus Close Combat Attack |
06 Dec 2012 |
48 pages |
| Authors:
Patrick R Wilde; ARMY COMMAND AND GENERAL STAFF COLL FORT LEAVENWORTH KS SCHOOL OF ADVANCED MILITARY STUDIES
|
| Since the origin of flight, the military has used aircraft to support military operations. This study focuses on one aspect of that support, the use of aerial delivered munitions in close proximity to soldiers on the ground to support freedom of maneuver. Close Air Support (CAS) and Close Combat Attack (CCA) exercise direct and indirect fires from aircraft to deliver required support and generate flexibility for maneuver operations, yet the ... |
|
| Asymptotic Description of Damping Mistuning Effects on the Forced Response of Turbomachinery Bladed Disks |
31 Jul 2012 |
44 pages |
| Authors:
Carlos Martel; UNIVERSIDAD POLITECNICA DE MADRID (SPAIN)
|
| This is the final report of the research grant FA8655-11-1-3084 issued by the European Office of Aerospace Research and Development. This research effort is devoted to the analysis of the effect of damping mistuning on the forced response of turbomachinery bladed disks using asymptotic techniques. In particular it includes: (i) the derivation of the simplified Asymptotic Mistuning Model (AMM) for the general problem of the forced response of a bladed ... |
|
| High-frequency Radar Cross Section (RCS) Approximation of a Thin Dielectric Spherical Shell |
Jul 2012 |
14 pages |
| Authors:
Geoffrey H Goldman; Frank J Crowne; ARMY RESEARCH LAB ADELPHI MD
|
| The high-frequency radar cross section (RCS) of a thin-filmed dielectric sphere in the far-field was approximated using a model based on two thin parallel dielectric plates. The results were compared to a solution developed by Andreasen based upon simplified boundary conditions. The models were used to estimate the RCS of a balloon with a diameter of 1 m. There was good agreement between the two methods. The RCS of the ... |
|
| Timely Effects: Organic Surface Fires and Airspace Doctrine in the 21st Century Joint Flight |
08 Jun 2012 |
109 pages |
| Authors:
Jonathan L Harvey; ARMY COMMAND AND GENERAL STAFF COLL FORT LEAVENWORTH KS
|
| The last 10 years of conflict have seen a dramatic increase of airspace users above the battlefield providing both opportunities and challenges to maneuver commanders. Assets operating overhead assist the commander in mission command; however, the additional airspace users also pose challenges to the maneuver commander's ability to employ organic surface fires. The primary research question this thesis seeks to answer is as follows: Does doctrine provide adequate guidance for ... |
|
| 11.72-sq cm Active-Area Wafer Interconnected PiN Diode Pulsed at 64 kA Dissipates 382 J and Exhibits an Action of 1.7 MA(sup 2)-s |
30 Jan 2012 |
5 pages |
| Authors:
M Snook; H Hearne; Ty McNutt; N El-Hinnawy; V Veliadis; B Nechay; S Woodruff; R S Howell; David Giorgi; Joe White; NORTHROP GRUMMAN SYSTEMS CORP LINTHICUM MD ELECTRONIC SYSTEMS
|
| The Silicon carbide (SiC) device area is presently limited by material and processing defects. To meet the large current handling requirements of modern power conditioning systems, the paralleling of a large number of devices is required. This can increase costs and complexity through wafer dicing, device soldering, the inclusion of ballast resistors, and the formation of multiple wire bonds. Furthermore, paralleling numerous discrete devices increases package volume and weight and ... |
|
| Influence of Metal Ion and Polymer Core on the Melt Rheology of Metallosupramolecular Films |
Jan 2012 |
12 pages |
| Authors:
Justin R Kumpfer; Jeong J Wie; John P Swanson; Frederick L Beyer; Michael E Mackay; Stuart J Rowan; CASE WESTERN RESERVE UNIV CLEVELAND OH
|
| Detailed rheological studies of metallo-supramolecular polymer films in the melt were performed to elucidate the influence of the metal ion and polymer components on their mechanical and structural properties. 4-Oxy-2,6-bis- (10-methylbenzimidazolyl)pyridine telechelic endcapped polymers with a low Tg core, either poly(tetrahydrofuran) or poly(ethylene-co-butylene), were prepared with differing ratios of Zn2+ and Eu3+ to determine the influence of polymer chain chemistry and metal ion on the properties. Increasing the amount of ... |
|
| Laminated Composite Sandwich Plates with a Weak Compressible Core Impacted by Blast Loading |
03 Nov 2011 |
39 pages |
| Authors:
Terry Hause; Sudhakar Arepally; ARMY TANK AUTOMOTIVE RESEARCH DEVELOPMENT AND ENGINEERING CENTER WARREN MI
|
| The governing theory of asymmetric sandwich plates with a first-order compressible core impacted by a Friedlander-type of blast has been presented and simplified for the case of symmetric cross-ply and single-layered orthotropic facings. In all cases, it was mentioned that all four edges are simply supported and freely movable. Results were then presented for this simplified case and validated against results found in the literature from R. S. Alwar et ... |
|
| Mexican Tax Reform: Look to the Russian Example |
31 Oct 2011 |
29 pages |
| Authors:
David V Ready; NAVAL WAR COLL NEWPORT RI JOINT MILITARY OPERATIONS DEPT
|
| Mexico suffers from a high underemployment rate of 25%, an extremely high poverty rate of 48%, a growing debt, low tax revenues, and low GDP growth. Without bettering this situation, the Government of Mexico will not be able to foster prosperity or afford any public expenditures to improve the security of the most unfortunate of its citizens. The Government of Mexico should follow sound economic theory and historical precedent and ... |
|
| Don't Come to the Dark Side: Acquisition Lessons from a Galaxy Far, Far Away |
Oct 2011 |
5 pages |
| Authors:
Dan Ward; DEPUTY ASSISTANT SECRETARY (AIR FORCE) (SCIENCE TECHNOLOGY AND ENGINEERING) WASHINGTON DC
|
| Yes, the Empire should stop building Death Stars. It turns out the DoD shouldn't build them either, metaphorically speaking. What sort of system fits into this category? I'll resist the urge to give specific examples and instead will simply point out that any enormous project that is brain-meltingly complex, ravenously consumes resources, and aims to deliver an Undefeatable Ultimate Weapon is well on its way to becoming a Death Star, ... |
|
| Time Reversal Techniques for Atomic Waveguides |
Sep 2011 |
18 pages |
| Authors:
William M Golding; ARMY RESEARCH LAB ADELPHI MD SENSORS AND ELECTRON DEVICES DIRECTORATE
|
| The modes of an atomic waveguide are analyzed using both the time reversal symmetry of the system and the Frobenius method of series solution to create a general, physically acceptable, solution of the radial differential equations. The general solution is used to obtain precise energies and wavefunctions by imposing various boundary conditions on the radial solution at some distance from the guide center. The use of the time reversal technique ... |
|
| Tracked Vehicle Dynamics Modeling and Simulation Methodology, with Control, using RecurDyn Software Package |
Sep 2011 |
13 pages |
| Authors:
Joseph Raymond; ARMY TANK AUTOMOTIVE RESEARCH DEVELOPMENT AND ENGINEERING CENTER WARREN MI
|
| Many Army vehicles require tracks in order to meet the tough mobility requirements for the Army mission profile. Modeling and Simulation (M&S) provides a large cost-savings and offers a quick turn-around when addressing vehicle performance issues. Once a baseline model is built for a given system, the model can be changed quickly to address different load or usage profiles and to determine the overall affect on the vehicle and its ... |
|
| Don't Supersize! Simplifying Defense Acquisition Reform |
Aug 2011 |
5 pages |
| Authors:
Marc J Raphael; DEPARTMENT OF THE AIR FORCE WASHINGTON DC
|
| In early 2009, shortly after the latest defense acquisition reform legislation, the Weapons Systems Acquisition Reform Act (WSARA) was signed by President Obama, I decided that as a defense acquisition professional, it would be good to study the history of such reform. I had been taunted by the old adage from high school history class -- that those who do not study the past are doomed to repeat it. My ... |
|
| Ride Quality Index - A New Approach to Quantifying the Comparison of Acceleration Responses of High Speed Craft |
Jun 2011 |
23 pages |
| Authors:
Michael Riley; Tim Coats; Kelly Haupt; Don Jacobson; NAVAL SEA SYSTEMS COMMAND WASHINGTON DC
|
| The objective of these briefing charts was to present a simplified approach to quantifying ride quality when comparing wave impacts for different craft, different sea states, different speeds or different gage locations. |
|
| Improvement of the Defense Supply Center Columbus (DSCC) Suggestion Program |
21 APR 2011 |
51 pages |
| Authors:
Sherrie Culbertson; INSTITUTE FOR DEFENSE AND BUSINESS CHAPEL HILL NC
|
| The research and analyses contained herein describe a number of areas and processes that should be improved in the DLA Land and Maritime Suggestion Program. Solutions provided, to include a marketing plan, improved web page prototype and simplified process flows are key to the increased utility expected through the implementation of the plan. The project focuses on 3 primary aspects: increasing employee participation and visibility of pending and previous suggestions; ... |
|
| FAR 13.5 Acquisition Streamlining: Observations and Recommendations for the Defense Logistics Agency |
Apr 2011 |
45 pages |
| Authors:
Daniel Shearer; DEFENSE ACQUISITION UNIV ABERDEEN PROVING GROUND MD
|
| This study leveraged the published work of Cory E. Yoder, CDR, U.S. Navy, Ret., Getting the Most from Acquisition Reforms: FAR 13.5 Test Provision for Simplified Acquisition Procedures, Commercial-item Acquisition (December 2006) for the purposes of making observations and recommendations for the Defense Logistics Agency. This study evaluated the foundational intent of acquisition reform compared to the Defense Logistics Agency's (DLA) performance in utilizing the streamlined procedures afforded under FAR ... |
|
| Function Extraction (FX) Research for Computation of Software Behavior: 2010 Development and Application of Semantic Reduction Theorems for Behavior Analysis |
Feb 2011 |
35 pages |
| Authors:
Richard Linger; Tim Daly; Mark Pleszkoch; CARNEGIE-MELLON UNIV PITTSBURGH PA SOFTWARE ENGINEERING INST
|
| For several years, the Software Engineering Institute (SEI) at Carnegie Mellon University has been engaged in a project to compute the behavior of software with mathematical precision to the maximum extent possible. Air Force Office of Scientific Research (AFOSR) sponsorship has played a key role in this effort. The general thrust of the research for AFOSR has been in technology for the following: (1) overcoming difficult aspects of behavior computation, ... |
|
| Solving Two-Level Optimization Problems with Applications to Robust Design and Energy Markets |
Jan 2011 |
223 pages |
| Authors:
Sauleh A Siddiqui; MARYLAND UNIV COLLEGE PARK
|
| This dissertation provides efficient techniques to solve two-level optimization problems. Three specific types of problems are considered. The first problem is robust optimization, which has direct applications to engineering design. Traditionally robust optimization problems have been solved using an inner-outer structure, which can be computationally expensive. This dissertation provides a method to decompose and solve this two-level structure using a modified Benders decomposition. This gradient-based technique is applicable to robust ... |
|
| Advancement of Techniques for Modeling the Effects of Atmospheric Gravity-Wave-Induced Inhomogeneities on Infrasound Propagation |
Sep 2010 |
11 pages |
| Authors:
Robert G Gibson; Douglas P Drob; David Broutman; Nathan W Winslow; BBN TECHNOLOGIES CAMBRIDGE MA
|
| Propagation studies of a growing number of infrasound observations indicate that fine-scale atmospheric inhomogeneities contribute to infrasonic arrivals that are not predicted by standard modeling techniques. In particular, gravity waves, or buoyancy waves, are believed to contribute to the multipath nature of infrasound propagation and to cause penetration of infrasound into the classical shadow zones that are predicted by conventional modeling techniques. Propagation modeling studies using basic parameterizations of gravity ... |
|
| Electromagnetic Field Control and Optimization Using Metamaterials |
Dec-2009 |
168 pages |
| Authors:
Jeffrey S McGuirk; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH GRADUATE SCHOOL OF ENGINEERING AND MANAGEMENT
|
| Transformation optics has shown the ability to cloak an object from incident electromagnetic radiation is possible. However, the material parameters are inhomogeneous, anisotropic, and, in some instances, singular at various locations. In order for a cloak to be practically realized, simplified parameter sets are required. However, the simplified parameters result in a degradation in the cloaking function. Constitutive parameters for simplified two-dimensional cylindrical cloaks have been developed with two material ... |
|
| Competition in Federal Contracting: An Overview of the Legal Requirements |
14-Apr-2009 |
|
| Authors:
Kate M Manuel; LIBRARY OF CONGRESS WASHINGTON DC CONGRESSIONAL RESEARCH SERVICE
|
 | This report describes the legal requirements pertaining to competition that presently apply to federal procurement contracts. Among other things, it discusses (1) what contracts are subject to competition requirements; (2) what constitutes full and open competition for government contracts; (3) what is meant by full and open competition after exclusion of sources; (4) circumstances permitting agencies to award contracts on the basis of other than full and open competition; (5) ... |
|
| The Effect of Values on System Development Project Outcomes |
Mar-2009 |
231 pages |
| Authors:
Daniel B Ward; NATIONAL AERONAUTICS AND SPACE ADMIN LANGLEY RESEARCH CENTER HAMPTON VA
|
| To understand why organizations make certain decisions and target certain outcomes, it is useful to understand their priorities and preferences, commonly referred to as values. This research explores the relationship between the technical values held by system development teams and the operational effectiveness of the systems those teams produce. Specifically, it examines the impact of a value set called FIST (Fast, Inexpensive, Simple, Tiny) on Department of Defense (DoD) and ... |
|
| Decentralized Cooperative Manipulation with a Swarm of Mobile Robots |
2009 |
7 pages |
| Authors:
Joel M. Esposito; NAVAL ACADEMY ANNAPOLIS MD DEPT OF WEAPONS AND SYSTEMS ENGINEERING
|
| In this paper we consider cooperative manipulation problems where a large group (swarm) of non-articulated mobile robots is trying to cooperatively control the velocity of some larger rigid body by exerting forces around its perimeter. We consider a second-order dynamic model for the object but use a simplified contact model. We seek solutions that require minimal information sharing among the swarm members. We present a velocity control law that is ... |
|
| Landing Ship Dock Replacement |
Aug-2008 |
39 pages |
| Authors:
Catherine Ingram; NAVAL SURFACE WARFARE CENTER CARDEROCK DIV BETHESDA MD SHIP SYSTEMS INTEGRATION AND DESIGN DEPARTMENT
|
| Current amphibious ships are capable of operating a variety of ship-to-shore connectors including displacement and non-displacement craft. However these ships are not optimized for operation of any particular landing craft and are sub-optimal for some of these craft. An investigation was undertaken considering future Landing Ship Dock concepts focused on operations using specific types of landing craft and intended to replace the LSD-41 vessels. Two concept designs are presented, one ... |
|
| A Level Set Based Geometrical Eulerian Approach to Computing High Frequency Radar Cross Sections and Multiphase Semiclassical Limits of the Schrodinger Equation |
30-Jun-2008 |
5 pages |
| Authors:
Stanley Osher; LEVEL SET SYSTEMS INC PACIFIC PALISADES CA
|
| Wave propagation in the high frequency regime can be simplified using the geometrical optics approximation. We obtained an eikonal approximation for the phase and transport equations for the amplitude. The general strategy used to find the phase is to solve for its level sets, called wave fronts. This same strategy works to compute semiclassical solutions of Schrodinger's equation, which is the main topic we studied here. Traditional obstacles faced in ... |
|
| Ensemble-Based Estimates of the Predictability of Wind-Driven Coastal Ocean Flow Over Topography |
Jan-2008 |
66 pages |
| Authors:
Chris Snyder; R M Samelson; Sangil Kim; OREGON STATE UNIV CORVALLIS COLL OF OCEANIC AND ATMOSPHERIC SCIENCES
|
| The predictability of coastal ocean circulation over the central Oregon shelf, a region of strong wind-driven currents and variable topography, is studied using ensembles of 50-day primitive-equation ocean model simulations with realistic topography, simplified lateral boundary conditions, and forcing from both idealized and observed wind time-series representative of the summer upwelling season. The main focus is on the balance, relevant to practical predictability, between deterministic response to known or well-predicted ... |
|
| Sound Speed and Attenuation in Multiphase Media |
30 SEP 2007 |
8 pages |
| Authors:
William M. Carey; Ronald A. Roy; BOSTON UNIV MA DEPT OF AEROSPACE AND MECHANICAL ENGINEERING
|
| One research goal developed from conducted shallow water (SW) acoustic transmission experiments in sandy-silty areas [1] revealed a nonlinear power law frequency-dependent attenuation at lower frequencies ( less than or equal to 1 kHz ) consistent with results reviewed in [2-4] and the observations by the ONR-HEP program. |
|
| Exploring Dimensionality Reduction for Text Mining |
04 MAY 2007 |
119 pages |
| Authors:
David G. Underhill; NAVAL ACADEMY ANNAPOLIS MD
|
| Text mining is the extraction of important information from a collection of textual data sources. For instance, text mining can be used to discover related concepts or to categorize previously unseen documents. In this age of information overload, text mining applications can potentially yield tremendous benefits to both individuals and organizations. However, the effectiveness of text mining is limited by the large volume of textual data, as well as its ... |
|
| Through-the-Wall Imaging from Electromagnetic Scattered Field Measurements |
01 MAR 2007 |
125 pages |
| Authors:
Jerry Kim; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| We investigate an inverse imaging problem for TWI (Through-the-wall Imaging) using frequencies between 500 GHz and 1 THz. Starting from first principles, this thesis uses Maxwells equations to develop a model for the transmission Greens function. This simplified model is then used in a Lippman-Schwinger integral equation to predict the scattered field associated with interrogating THz waves. We investigate the effects of wave propagation through isotropic media, and present methods ... |
|
| Quick-Turn Finite Element Analysis for Plug-and-Play Satellite Structures |
MAR 2007 |
118 pages |
| Authors:
Jeffrey E. Naff; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING AND MANAGEMENT
|
| Plug-and-play (PnP) satellite construction is a key component of the US Air Force Operational Responsive Space (ORS) effort. The goal of ORS is to provide mission specific satellite support by configuring and launching a satellite to a selected orbit within days of the request. One major challenge during the time limited process is to accurately predict the response of the satellite to harmonic loads that occur during launch and satellite ... |
|
| A Direction Finding System for Transient Signals |
MAR 2007 |
8 pages |
| Authors:
Jr. Swenson George W.; Larry L. Pater; Michael J. White; ENGINEER RESEARCH AND DEVELOPMENT CENTER CHAMPAIGN IL CONSTRUCTION ENGINEERING RESEARCH LAB
|
| Currently deployed direction finders used with radio-tagged animals have proved to be of great value in the study of endangered species of wildlife. The automated collection of directional data, supplanting or supplementing individual researchers with hand-held instruments, has permitted major increases in research productivity. However, only one design of a suitable automated instrument exists on the market. It is available from only one source, in limited quantities, and is still ... |
|
| Naive Realism in Terrain Appreciation |
2007 |
6 pages |
| Authors:
Harvey S. Smallman; Maia B. Cook; Daniel I. Manes; Michael B. Cowen; PACIFIC SCIENCE AND ENGINEERING GROUP INC SAN DIEGO CA
|
| Previously, we have shown that shaded perspective view (3-D) displays are better for understanding the shape and rough layout of terrain than conventional 2-D views. We have coined the term Naive Realism for users' misplaced, blanket faith in these 3-D displays (Smallman & St. John, 2005). There are hints in the individual difference literature that those of low spatial ability may be particularly prone to Naive Realism. Here, we integrate ... |
|
| Piled-Slab Searches |
01-Dec-2006 |
9 pages |
| Authors:
Alan Washburn; NAVAL POSTGRADUATE SCHOOL MONTEREY CA DEPT OF OPERATIONS RESEARCH
|
| This paper deals with the conflict between simplicity and optimality in searching for a stationary target whose location is distributed in two dimensions, thus continuing an analysis that was begun in World War II. The search is assumed to be of the "piled-slab" type, where each slab consists of a uniform search of some simple region. The measure of simplicity is the number of regions (smaller is simpler). If each ... |
|
| Capitalizing on Commercial-Item Designation Provisions of FAR 13.5: Getting the Most from Limited Resources |
DEC 2006 |
129 pages |
| Authors:
Jason M. Johnson; Brian K. Simonson; Mark A. Ziegler; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| The past decade has seen a significant change in business practices within the Federal contracting arena. Acquisition reform initiatives have fundamentally transformed the protocols and processes the Federal Government utilizes to procure billions of dollars worth of goods and services every year. Reforms provided under the Federal Acquisition Streamlining Act (FASA), the Federal Acquisition Reform Act (FARA), and the Services Acquisition Reform Act (SARA), along with ensuing regulatory provisions in ... |
|
| Estimating Mass Discharge From Dense Nonaqueous Phase Liquid Source Zones Using Upscaled Mass Transfer Coefficients: An Evaluation Using Multiphase Numerical Simulations |
28 NOV 2006 |
14 pages |
| Authors:
John A. Christ; C. A. Ramsburg; Kurt D. Pennell; Linda M. Abriola; AIR FORCE ACADEMY COLORADO SPRINGS CO
|
| Difficulties associated with identifying the dense nonaqueous phase liquid (DNAPL) source zone architecture at the field scale, combined with the computational costs of field-scale DNAPL dissolution simulations, have motivated the development of a number of simplified models that rely upon upscaled (i.e., domain-averaged) mass transfer coefficients to approximate field-scale dissolution processes. While conceptually attractive, these upscaled models have yet to be fully evaluated for prediction of mass recovery from a ... |
|
| Parameter Estimation Versus Homogenization Techniques in Time-Domain Characterization of Composite Dielectrics |
22 AUG 2006 |
29 pages |
| Authors:
H. T. Banks; V. A. Bokil; N. L. Gibson; NORTH CAROLINA STATE UNIV AT RALEIGH CENTER FOR RESEARCH IN SCIENTIFIC COMPUTATION
|
| We compare an inverse problem approach to parameter estimation with homogenization techniques for characterizing the electrical response of composite dielectric materials in the time domain. We first consider an homogenization method, based on the periodic unfolding method, to identify the dielectric response of a complex material with heterogeneous micro-structures which are described by spatially periodic parameters. We also consider electromagnetic interrogation problems for complex materials assuming multiple polarization mechanisms with ... |
|
| Analysis of the Assignment Scheduling Capability for Unmanned Aerial Vehicles (ASC-U) Simulation Tool |
JUN 2006 |
131 pages |
| Authors:
Christopher J. Nannini; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| The U.S. Army Training and Doctrine Command (TRADOC) Analysis Center (TRAC) and the Modeling, Virtual Environments, and Simulations Institute (MOVES) at the Naval Postgraduate School, Monterey, California developed the Assignment Scheduling Capability for UAVs (ASC-U) simulation to assist in the analysis of unmanned aerial vehicle (UAV) requirements for the current and future force. ASC-U employs a discrete event simulation coupled with the optimization of a linear objective function. At regular ... |
|
| Are We Using Legislation to Its Fullest Potential? An In-Depth Look at Simplified Acquisitions in the Marine Corps |
DEC 2005 |
81 pages |
| Authors:
Laurie A. Gillespie; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| The purpose of this MBA Project was to investigate and provide a comprehensive overview of the history of simplified acquisitions, to build a model for theoretical potential of use, and then to compare what is currently being done at major contracting offices within the Marine Corps to see if the legislation is being used to the fullest extent. This comparison is to ensure that the Marine Corps is maximizing effectiveness ... |
|
| Environmental Complexity and Stochastic Modeling of High-Frequency Acoustic Scattering From the Seafloor |
05 AUG 2005 |
12 pages |
| Authors:
Christopher D. Jones; WASHINGTON UNIV SEATTLE APPLIED PHYSICS LAB
|
| Models of acoustic scattering from the seafloor generally assume that sediment heterogeneity is statistically homogeneous with single-scale correlation structure. Current statistical descriptions of the seafloor are incapable of capturing information about complex seafloor heterogeneities that are often encountered in marine environments (e.g. non-uniform or clustered scatterers, patchiness in the sediment physical properties). Seafloor complexity is due to a variety of processes including bioturbation (burrows, fish pock marks), biogenic deposits (shell ... |
|
| Path Planning by Unmanned Air Vehicles for Engaging an Integrated Radar Network |
AUG 2005 |
17 pages |
| Authors:
Reid A. Larson; Meir Pachter; Mark J. Mears; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH
|
| A growing concept in the field of unmanned air vehicles (UAVs) is the idea of using a team of cooperating vehicles to participate in electronic countermeasures, defined here as jamming or deception techniques. A UAV may be tasked to engage a radar using noise jamming to mask its radar return or that of another vehicle. Similarly, a UAV may be assigned to deceive a radar by directing a delayed signal ... |
|
| A Wall-Function Approach to Incorporating Knudsen-Layer Effects in Gas Micro Flow Simulations |
13 JUL 2005 |
|
| Authors:
D. A. Lockerby; J. M. Reese; M. A. Gallis; KING'S COLL LONDON (UNITED KINGDOM) DEPT OF MECHANICAL ENGINEERING
|
| For gas flows in microfluidic configurations, the Knudsen layer close to the wall can comprise a substantial part of the entire flowfield and has a major effect on quantities such as the mass flow rate through micro devices. The Knudsen layer itself is characterized by a highly nonlinear relationship between the viscous stress and the strain rate of the gas, so even if the Navier-Stokes equations can be used to ... |
|
| To TPFDD or Not to TPFDD: Is the TPFDD Outdated for Expeditionary US Military Operations? |
26 MAY 2005 |
60 pages |
| Authors:
Brian M. Newberry; ARMY COMMAND AND GENERAL STAFF COLL FORT LEAVENWORTH KS SCHOOL OF ADVANCED MILITARY STUDIES
|
| Commanders routinely undervalue logistics, despite the fact that logistics is arguably nine-tenths of the formula for winning. For the United States, this reality has significant consequences since every war beginning with the Spanish-American War in 1898 to the latest Operation Iraqi Freedom (OIF) conflict has relied on moving U.S. forces over extended distances. Indeed, despite the importance of logistics in an expeditionary age, the U.S. military has not settled on ... |
|
| On Static Reachability Analysis of IP Networks |
01-Mar-2005 |
15 pages |
| Authors:
Geoffrey G Xie; Jibin Zahn; David A Maltz; Hui Zhang; Albert Greenberg; Gisli Hjalmtysson; Jennifer Rexford; CARNEGIE-MELLON UNIV PITTSBURGH PA
|
| The primary purpose of a network is to provide reachability between applications running on end hosts. In this paper, we describe how to compute the reachability a network provides from a snapshot of the configuration state from each of the routers. Our primary contribution is the precise definition of the potential reachability of a network and a substantial simplification of the problem through a unified modeling of packet filters and ... |
|
| Tactical Decision Aid For Unmanned Vehicles In Maritime Missions |
MAR 2005 |
88 pages |
| Authors:
Daniel Duhan; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| An increasing number of unmanned vehicles (UV) are being incorporated into maritime operations as organic elements of Expeditionary and Carrier Strike Groups for development of the recognized maritime picture. This thesis develops an analytically-based planning aid for allocating UVs to missions. Inputs include the inventory of UVs, sensors, their performance parameters, and operational scenarios. Operations are broken into mission critical functions: detection, identification, and collection. The model output assigns aggregated ... |
|
| Report of the Defense Science Board Task Force on Management Oversight in Acquisition Organizations |
MAR 2005 |
45 pages |
| Authors:
DEFENSE SCIENCE BOARD WASHINGTON DC
|
| Recent events in the Air Force surrounding the illegal actions of former Principal Deputy Assistant Secretary Darleen Druyun highlighted the need to review the management and oversight structure of acquisition activities in the Department of Defense (DoD). DoD, through the Undersecretary of Defense for Acquisition, Technology, and Logistics USD(AT&L), established the Defense Science Board (DSB) Task Force on Management Oversight of Acquisition Organizations to examine its acquisition structures and processes; ... |
|
| Upgrading Distributed Applications with the Version Manager |
MAR 2005 |
20 pages |
| Authors:
Mukesh Agrawal; Suman Nath; Srinivasan Seshan; CARNEGIE-MELLON UNIV PITTSBURGH PA SCHOOL OF COMPUTER SCIENCE
|
| Developers and managers of distributed systems today face a difficult choice. To provide for the evolution of their systems, they can either require that the software running on all nodes is interoperable, or they can shut down the entire system when an upgrade is required. The former complicates the life of system developers, while the latter annoys users. The authors propose Version Manager, a middle ground between these approaches. Version ... |
|
| Thermal Characteristics of Pitch Based Carbon Foam and Phase Change Materials |
MAR 2005 |
76 pages |
| Authors:
Kevin W. Wierschke; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING AND MANAGEMENT
|
| Phase-change thermal energy storage devices offer thermal control systems an option that allows a smaller heat sink to be used by absorbing the thermal energy quickly and storing it in the phase change to prevent failure of electronic components and then slowly releasing the heat to the heat sink. This paper experimentally determined the transient response of carbon foam with a phase-change material by measuring the response to a step ... |
|
| Three-Dimensional Hydrodynamic Model for Prediction of Falling Cylinder Through Water Column |
2005 |
12 pages |
| Authors:
Peter C. Chu; Chenwu Fan; Ashley Evans; Anthony F. Gilles; Peter Fleischer; NAVAL POSTGRADUATE SCHOOL MONTEREY CA DEPT OF OCEANOGRAPHY
|
| A three dimensional hydrodynamic model based on triple coordinate systems is developed to predict translation and orientation of falling rigid cylinder through the water column: earth-fixed coordinate (E-coordinate), cylinder 5 main-axis following coordinate (M-coordinate), and hydrodynamic force following coordinate (F- coordinate). Use of the triple coordinate systems and the transforms among them leads to the simplification of the dynamical system. The body and buoyancy forces and their moments are easily ... |
|
| Direct-Connect Performance Evaluation of a Valveless Pulse Detonation Engine |
DEC 2004 |
79 pages |
| Authors:
Nicole K. Wittmers; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| Operational characteristics of a valveless pulse detonation engine system were characterized by experimental measurements of thrust, fuel flow, and internal gas dynamics. The multi-cycle detonation experiments were performed on an axis-symmetric engine geometry operating on an ethylene/air mixture. The detonation diffraction process from a small initiator combustor to a larger diameter main combustor in a continuous airflow configuration was evaluated during multi-cycle operation of a pulse detonation engine and was ... |
|
| Construction and Testing of Compact Low-Noise Hydrophones with Extended Frequency Response |
JUN 2004 |
|
| Authors:
Konstantinos Bakas; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| A simple, low-noise hydrophone design with internal preamplifier is presented. This design is similar to published designs and is a variation of the design developed in the Naval Postgraduate School thesis by Miguel Alvarado in 2003, except that several features have been improved. These include a simplification of the structure and its modes of vibration, a large reduction in package diameter and the effect its acoustic diffraction has on sensitivity, ... |
|
Reports by Keyword(s)
SIMPLIFICATION
