| Ascending Stairway Modeling: A First Step Toward Autonomous Multi-Floor Exploration |
Oct 2012 |
4 pages |
| Authors:
Jeffrey A Delmerico; Jason J Corso; David Baran; Philip David; Julian Ryde; ARMY RESEARCH LAB ADELPHI MD
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 | Many robotics platforms are capable of ascending stairways, but all existing approaches for autonomous stair climbing use stairway detection as a trigger for immediate traversal. In the broader context of autonomous exploration the ability to travel between floors of a building should be compatible with path planning, such that the robot can traverse a stairway at a time that is appropriate to its navigation goals. No system yet presented is ... |
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| Wave Height and Water Level Variability on Lakes Michigan and St Clair |
Oct 2012 |
183 pages |
| Authors:
Jeffrey A Melby; Norberto C Nadal-Caraballo; Yamiretsy Pagan-Albelo; Bruce Ebersole; ENGINEER RESEARCH AND DEVELOPMENT CENTER VICKSBURG MS COASTAL AND HYDRAULICS LAB
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| The Great Lakes are subject to coastal flooding as a result of severe storms. Strong winds blowing across the surface of the lakes produce high waves and surge. Variations in lake levels due to decadal scale variations in precipitation and anthropogenic activities affect the risk of flooding. In this report, historical storm climatology on Lakes Michigan and St Clair, and the resulting measured waves and water levels, are analyzed in ... |
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| Optimal Use of TDOA Geo-Location Techniques Within the Mountainous Terrain of Turkey |
Sep 2012 |
170 pages |
| Authors:
Volkan Tas; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| Emitter location finding enables important functionality for both military and civilian applications. GPS is the most recognized and widely used positioning system, but it is a receiver location system that functions in a markedly different manner from emitter location. Many geo-location techniques predate and have been proposed as an alternative to GPS. Some of the more commonly used and exploited of these techniques are angle of arrival, time of arrival, ... |
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| Creating Network Attack Priority Lists by Analyzing Email Traffic With Predefined Profiles |
Sep 2012 |
98 pages |
| Authors:
Eric J Merritt; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING
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| Networks can be vast and complicated entities consisting of both servers and workstations that contain information sought by attackers. Searching for specific data in a large network can be a time consuming process. Vast amounts of data either passes through or is stored by various servers on the network. However, intermediate work products are often kept solely on workstations. Potential high value targets can be passively identified by comparing user ... |
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| Assessing the Minimum Number of Synchronization Triggers Necessary for Temporal Variance Compensation in Commercial Electroencephalography (EEG) Systems |
Sep 2012 |
14 pages |
| Authors:
Keith W Whitaker; W D Hairston; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD HUMAN RESEARCH AND ENGINEERING DIRECTORATE
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| This technical note describes the differences in recording when events happen between several commercially-oriented electroencephalography (EEG) recording systems. The four systems examined, Emotiv's EPOC, Biosemi's ActiveTwo, Advanced Brain Monitoring's B-Alert X10 and Quasar's prototype represent different approaches to the problem of recording brain activity in human subjects. We found that the EPOC introduces significantly more error in recording event timing, though this issue is present in all systems. Furthermore, we ... |
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| Analysis of the Computer, Meteorological Data - Profiler's (CMD-P) Capability to Assimilate Regional Radiosonde Data |
Sep 2012 |
33 pages |
| Authors:
P Haines; J Cogan; T Jameson; J Swanson; ARMY RESEARCH LAB WHITE SANDS MISSILE RANGE NM
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| The Product Manager (PM) for Meteorological and Target Identification Capabilities (MaTIC) developed a laptop-based version of the Meteorological Measuring Set-Profiler (MMS-P) that should replicate the capabilities of the latest currently fielded version, the MMS-P Block I ? Version 2 (B1v2). The laptop is a standard dual-processor VT Miltope CHS laptop. The B1v2 can generate all types of artillery meteorological (MET) messages. The PM funded the U.S. Army Research Laboratory (ARL) ... |
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| Effects of Processing and Powder Size on Microstructure and Reactivity in Arrested Reactive Milled Al + Ni |
May 2012 |
19 pages |
| Authors:
Eric B Herbold; Jennifer L Jordan; N N Thadhani; AIR FORCE RESEARCH LAB EGLIN AFB FL MUNITIONS DIRECTORATE
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| Ball-milling Al-metal powders can result in self-sustaining high-temperature synthesis in intermetallic-forming systems. Here, Al and Ni powders with similar composition are used to investigate how microstructural differences affect the measured time to reaction (TTR) between powders of different sizes processed under milling conditions specified by statistically designed experiments. Linear statistical models predicting the TTR and the change in temperature (DT) are built from these experimental results. The time required to ... |
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| Coronal Fe XIV Emission During the Whole Heliosphere Interval Campaign (Postprint) |
05 Apr 2012 |
10 pages |
| Authors:
Richard C Altrock; AIR FORCE RESEARCH LAB KIRTLAND AFB NM SPACE VEHICLES DIRECTORATE
|
| Solar Cycle 24 is having a historically long and weak start. Observations of the Fe XIV corona from the Sacramento Peak site of the National Solar Observatory show an abnormal pattern of emission compared to observations of Cycles 21, 22, and 23 from the same instrument. The previous three cycles have shown a strong, rapid Rush to the Poles (previously observed in polar crown prominences and earlier coronal observations) in ... |
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| It's About Time -- Understanding China's Strategic Patience |
18 Mar 2012 |
32 pages |
| Authors:
Brian M Kennedy; ARMY WAR COLL CARLISLE BARRACKS PA
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| This paper will explore the application of time as a critical factor in exercising the elements of national power, specifically differences in how the concept of time is applied by the United States and China. The paper will discuss diplomatic, informational, military, and economic aspects of time, and examine whether time plays a critical role in each element of national power. During an analysis of the military element of power, ... |
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| Modeling of Helicopter Pilot Misperception During Overland Navigation |
Mar 2012 |
110 pages |
| Authors:
Bradley T Cowden; NAVAL POSTGRADUATE SCHOOL MONTEREY CA DEPT OF OPERATIONS RESEARCH
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| This thesis provides a framework to model human belief and misperception in helicopter overland navigation. Helicopter overland navigation is a challenging mission area because it is a complex cognitive task, and failing to recognize when the aircraft is off-course can lead to operational failures and mishaps. A human-in-the-loop experiment to investigate pilot misperception during simulated overland navigation by analyzing actual navigation trajectory, pilots' perceived location, and corresponding confidence levels was ... |
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| The Nation That Cried Lone Wolf: A Data-Driven Analysis of Individual Terrorists in the United States Since 9/11 |
Mar 2012 |
111 pages |
| Authors:
Charles A Eby; NAVAL POSTGRADUATE SCHOOL MONTEREY CA DEPT OF NATIONAL SECURITY AFFAIRS
|
| Lone-wolf terrorist attacks have occurred in the United States throughout the country's history. Attempted attacks from individual terrorists unaffiliated with terrorist groups may be becoming more prevalent. Both the general public and government officials acknowledge the presence and importance of these attacks; however, relatively little literature exists on the subject compared to group terrorism. Much of the information on lone wolves has been established by case study, inference, and known ... |
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| On the Renormalization of the Covariance Operators |
Feb 2012 |
14 pages |
| Authors:
Max Yaremchuk; Matthew Carrier; NAVAL RESEARCH LAB STENNIS DETACHMENT STENNIS SPACE CENTER MS OCEANOGRAPHY DIV
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| Many background error correlation (BEC) models in data assimilation are formulated in terms of a smoothing operator B, which simulates the action of the correlation matrix on a state vector normalized by respective BE variances. Under such formulation, B has to have a unit diagonal and requires appropriate renormalization by rescaling. The exact computation of the rescaling factors (diagonal elements of B) is a computationally expensive procedure, which needs an ... |
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| Microwave-Irradiation-Assisted HVAC Filtration for Inactivation of Viral Aerosols (Postprint) |
Feb 2012 |
11 pages |
| Authors:
Myung-Heui Woo; Chang-Yu Wu; Adam Grippin; Joseph D Wander; FLORIDA UNIV GAINESVILLE DEPT OF ENVIRONMENTAL ENGINEERING SCIENCES
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| Viral aerosols collected on a filter medium can reaerosolize and the filter can serve as a fomite. This study evaluated the inactivation efficiency (IE) achieved by filtration coupled with microwave irradiation. To test in-flight microwave decontamination, microwave irradiation was applied to coupons cut from a ventilation filter and supported on a SiC disk during three cycles of selected irradiation times (1, 2.5, 5, and 10 min) per 10 min of ... |
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| On-chip Electrical Soliton Oscillators for Picosecond Pulse Self-Generation and THz Electronics |
17 Jan 2012 |
12 pages |
| Authors:
Donhee Ham; HARVARD UNIV CAMBRIDGE MA
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| Solitons are pulsed waves exhibiting unique nonlinear properties. In electronics domain, electrical solitons had been passively produced by using nonlinear transmission lines. Prior to this proposal, our group built, for the first time, an active electrical circuit in a discrete platform, which robustly self-generated a stable, periodic train of electrical solitons. This was achieved by combining a nonlinear transmission line with a specially designed amplifier in a circular topology. The ... |
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| Anomalous Photon-Assisted Tunneling in Graphene |
Jan 2012 |
10 pages |
| Authors:
Andrii Iurov; Godfrey Gumbs; Oleksiy; Roslyak; Danhong Huang; AIR FORCE RESEARCH LAB KIRTLAND AFB NM
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| We investigated the transmission of Dirac electrons through a potential barrier in the presence of circularly polarized light. An anomalous photon-assisted enhanced transmission is predicted and explained. It is demonstrated that the perfect transmission for nearly head-on collision in infinite graphene is suppressed in gapped dressed states of electrons, which is further accompanied by a shift of peaks as a function of the incident angle away from head-on collision. In ... |
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| Multivariable and Multigroup Receiver Operating Characteristics Curve Analyses for Qualitative and Quantitative Analysis |
Jan 2012 |
45 pages |
| Authors:
Waleed M Maswadeh; A P Snyder; ARMY EDGEWOOD CHEMICAL BIOLOGICAL CENTER APG MD RESEARCH AND TECHNOLOGY DIR
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| An algorithm was developed using univariate statistics to reduce and analyze multivariate and multiple group data sets. The algorithm features the quantitative and selectivity figures of merit of receiver operating characteristics (ROC) curve methodology. This merging of two separate statistical analysis techniques resulted in the ability to address more than one variable in more than two experimental groups in a systematic fashion. The classic Fisher iris flower data set is ... |
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| Modeling and Simulation of Mortar Fin Tooling Using Cyclic Symmetry |
Jan 2012 |
15 pages |
| Authors:
Shana Groeschler; L Reinhardt; Matthew Glaser; ARMY ARMAMENT RESEARCH DEVELOPMENT AND ENGINEERING CENTER PICATINNY ARSENAL NJ
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| Cyclic symmetry is a method in finite element analysis that allows for the simulation of an entire cyclically symmetrical structure based on a model of one repeating sector. The reduction of model size obtained using cyclic symmetry can significantly reduce computational cost. This technique was employed to optimize the three pronged tooling design used to assemble mortar fins to the mortar body. Using cyclic symmetry, only one-third of the model ... |
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| A Matched Field Processing Framework for Coherent Detection Over Local and Regional Networks (Postprint) |
30 Dec 2011 |
14 pages |
| Authors:
Tormod Kvaerna; David B Harris; Steven J Gibbons; Douglas A Dodge; NORSAR KJELLER (NORWAY)
|
| The objective of this study has been to develop a data-adaptive matched field procedure to detect coherently and incoherently across networks of stations at local and regional distances. The detector extends the single-phase matched field processing approach to detection using the entire waveform. The procedure is based upon a narrowband signal representation that exposes the invariant spatial and temporal correlation structure of network signals from repeating sources. The matched field ... |
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| Dislocation Transport in Continuum Crystal Plasticity Simulations (First-year Report) |
Dec 2011 |
32 pages |
| Authors:
Richard Becker; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD
|
| Continuity of dislocation flux across element boundaries is introduced into a non-local, explicit finite element code using a continuum crystal plasticity constitutive model. In addition to providing enhanced coupling of the deformation field among neighboring elements, dislocation fluxes are integrated through time to give an estimate of dislocation gradients that serve as a strengthening mechanism. The results demonstrate the effects of dislocation flux continuity and the realization of a size ... |
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| Emergency Responder Personal Preparedness |
Dec 2011 |
107 pages |
| Authors:
Chris A Kelenske; NAVAL POSTGRADUATE SCHOOL MONTEREY CA DEPT OF NATIONAL SECURITY AFFAIRS
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| Citizens have an expectation that emergency responders will come to their aid during emergencies. There is the general assumption that these responders and the agencies they work for are prepared for any type of event. With a core element of any disaster response being the capability of the emergency responders, a lack of personal preparedness by emergency response personnel is likely to be highly detrimental and will reduce their capability ... |
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| Stochastic Network Interdiction for Optimizing Defensive Counter Air Operations Planning |
Dec 2011 |
73 pages |
| Authors:
Charalampos I Tsamtsaridis; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| This thesis describes a stochastic, network interdiction optimization model to guide defensive, counter-air (DCA) operations planning. We model a layered, integrated air-defense system, which consists of fighter and missile engagement zones. We extend an existing two-stage, stochastic, generalized-network interdiction model by Pan, Charlton and Morton, and adapt it to DCA operations planning. The extension allows us to handle multiple-type interdiction assets, and constrain the attacker's flight path by the maximum ... |
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| Optimal Pulse Shapes for SHPB Tests on Soft Materials |
Dec 2011 |
20 pages |
| Authors:
Mike Scheidler; John Fitzpatrick; Reuben Kraft; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD WEAPONS AND MATERIALS RESEARCH DIRECTORATE
|
| For split Hopkinson pressure bar (SHPB) tests on soft materials, the goals of homogeneous deformation and uniform uniaxial stress in the specimen present experimental challenges, particularly at higher strain rates. It has been known for some time that attainment of these conditions is facilitated by reducing the thickness of the specimen or by appropriately shaping the loading pulse. Typically, both methods must be employed. Pulse shapes are often tailored to ... |
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| Fluidically Augmented Nozzles for Pulse Detonation Engine Applications |
Dec 2011 |
147 pages |
| Authors:
Larry R Smith; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
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| Pulse Detonation Engines (PDE) operate in a cyclic manner resulting in large changes in the combustion chamber pressure. The widely varying pressure ratio between the chamber and nozzle exit makes it difficult to efficiently produce thrust since a fixed area ratio exhaust nozzle would operate off design nearly the entire cycle. Therefore, a nozzle with the capability to create the necessary area ratio throughout the cycle is required to produce ... |
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| The Effects of Time Advance Mechanism on Simple Agent Behaviors in Combat Simulations |
Dec 2011 |
13 pages |
| Authors:
Ahmed A Al Rowaei; Arnold H Buss; Stephen Lieberman; NAVAL POSTGRADUATE SCHOOL MONTEREY CA MODELING VIRTUAL ENVIRONMENTS AND SIMULATION (MOVES)
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| We investigate the effects of time advance mechanisms on the behavior of agents in combat simulations using some simple scenarios relevant to combat and agent-based models. We implement these simulation designs in two modeling packages that illustrate the differences between discrete-time simulation (DTS) and discrete-event simulation (DES) methodologies. Many combat models use DTS as their simulation time advance mechanism. We demonstrate that the presence and size of the time step ... |
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| Integrated Warfighter Biodefense Program (IWBP) - Next Phase |
10 Nov 2011 |
36 pages |
| Authors:
Franklin T Abbott; Ganesh Vaidyanathan; QUANTUM LEAP INNOVATIONS INC NEWARK DE
|
| The aim of the Integrated Warfighter Biodefense Program (IWBP) is to develop innovative technology that can be deployed to prevent U.S. armed forces from becoming battle or non-battle casualties, and especially to reduce morbidity and mortality throughout the increasingly complex battlespace of current operations. In this summary of the next phase of work on IWBP we report the continued development of novel software that provides a simulation environment for modeling ... |
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| Know the Star, Know the Planet. 2. Speckle Interferometry of Exoplanet Host Stars |
Nov 2011 |
7 pages |
| Authors:
Brian D Mason; William I Hartkopf; Deepak Raghavan; John P Subasavage; Jr Roberts Lewis C; Nils H Turner; Theo A ten Brummelaar; NAVAL OBSERVATORY WASHINGTON DC
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| A study of the host stars to exoplanets is important for understanding their environment. To that end, we report new speckle observations of a sample of exoplanet host primaries. The bright exoplanet host HD 8673 (= HIP 6702) is revealed to have a companion, although at this time we cannot definitively establish the companion as physical or optical. The observing lists for planet searches and for these observations have for ... |
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| Predictive Cache Modeling and Analysis |
Nov 2011 |
52 pages |
| Authors:
Russell Kegley; Jonathan Preston; Brian Dougherty; Jules White; Anirudda Gokhale; LOCKHEED MARTIN AERONAUTICS CO FORT WORTH TX
|
| This work applied particle swarm heuristic optimization techniques to the problem of finding a near-optimal order in which to schedule tasks in a real-time embedded system in order to minimize cache miss rates experienced by the software. Reducing the number of cache misses is an important component of runtime execution efficiency. We demonstrated runtime reductions of 3-5% in execution time, significant for embedded systems attempting to add new capability without ... |
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| Optimal Control of Batteries with Fully and Partially Available Rechargeability |
11 Oct 2011 |
11 pages |
| Authors:
Tao Wang; Christos G Cassandras; BOSTON UNIV BROOKLINE MA CENTER FOR INFORMATION AND SYSTEMS ENGINEERING
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| Motivated by the increasing dependence of many systems on battery energy, we study the problem of optimally controlling how to discharge and recharge a non-ideal battery so as to maximize the work it can perform over a given time period and still maintain a desired final energy level. Modeling a battery as a dynamic system, we adopt a Kinetic Battery Model (KBM) and formulate a finite-horizon optimal control problem when ... |
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| Low Strain Rate Failure of Compliant Flexures |
Oct 2011 |
28 pages |
| Authors:
Matthew J Santer; IMPERIAL COLL LONDON (UNITED KINGDOM) DEPT OF AERONAUTICS
|
| This project investigates the time-dependent properties of thin carbon fiber composite flexures when they are held in a folded (stowed) configuration for long periods of time. The resulting behavior is shown to be complex and time dependent in an experimental program to determine the full field strain and evolution of microstructural damage. The program uses a developed experimental rig which uses digital image correlation to measure the strain behavior over ... |
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| Physical and Biological Effects on Tide Flat Sediment Stability and Strength - Phase 2 |
30 Sep 2011 |
5 pages |
| Authors:
Robert A Wheatcroft; OREGON STATE UNIV CORVALLIS COLL OF OCEANIC AND ATMOSPHERIC SCIENCES
|
| This research is part of the Tidal Flats Department Research Initiative (DRI) that (amongst other goals) is focused on understanding the controls of sediment strength over multiple time and space scales on the mudflats of Willapa Bay, Washington. My role in the DRI is to: (1) obtain high-resolution profiles of sediment bulk density to compare against erodibility measured by other investigators, and (2) collect time series data on near-surface porosity, ... |
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| The Effect of Time-Advance Mechanism in Modeling and Simulation |
Sep 2011 |
318 pages |
| Authors:
Ahmed A Alrowaie; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| As the discipline of Modeling and Simulation (M&S) becomes more complex, modelers are faced with mounting challenges to design and analyze simulations that effectively address difficult problems across military, industrial, and societal fields. Understanding the effects of time-advance mechanisms (TAMs) is essential to making advances in the design and use of M&S across a wide variety of domains. We perform a series of empirical studies to characterize and compare the ... |
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| Combining Analyst and Waveform-Correlation-Based Arrival Time Measurements in the Bayesloc Multiple-Event Location Algorithm |
Sep 2011 |
8 pages |
| Authors:
Stephen C Myers; Gardar Johannesson; Douglas A Dodge; Nathan A Simmons; LAWRENCE LIVERMORE NATIONAL LAB CA
|
| We add relative arrival-time measurements that are derived from waveform correlation to the Bayesloc multiple-event location algorithm. Bayesloc is a formulation of joint probability over event locations, travel time corrections phase labels, and arrival-time measurement errors. The Bayesloc formulation is hierarchical with distinct statistical models for each component of the multiple-event system, including prior constraints for any of the parameters. Bayes' Theorem allows calculation of the joint probability for hypothesized ... |
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| Scalable Management of Enterprise and Data-Center Networks |
Sep 2011 |
151 pages |
| Authors:
Minlan Yu; PRINCETON UNIV NJ DEPT OF COMPUTER SCIENCE
|
| The networks in campuses, companies, and data centers are growing larger and becoming more complicated to manage. Today, network operators devote tremendous time and effort to three key management tasks--routing, access control, and troubleshooting. Rather than trying to make today's brittle networks easier to manage, we focus on new network designs that are inherently easier to manage and scale to many hosts, switches, and applications. We design and develop a ... |
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| Army and Marine Corps Training: Metrics Needed to Assess Initiatives on Training Management Skills |
JUL 2011 |
32 pages |
| Authors:
Sharon Pickup; Michael Ferren; Jerome Brown; Kenya Jones; Ashley Lipton; Lonnie McAllister; Terry Richardson; GOVERNMENT ACCOUNTABILITY OFFICE WASHINGTON DC
|
| Marine Corps forces have deployed repeatedly with limited time between deployments. At their home stations, combat training centers, and other locations, units have focused their limited training time on training for counterinsurgency operations. Prior to deploying, units also conduct a large scale exercise referred to as a culminating training event. With the drawdown of forces in Iraq, the services have begun to resume training for a fuller range of offensive, ... |
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| A Study on Alpha Case Depth in Ti-6Al-2Sn-4Zr-2Mo (PREPRINT) |
Jul 2011 |
13 pages |
| Authors:
Kevin S McReynolds; Seshacharyulu Tamirisakandala; UES INC DAYTON OH
|
| Isothermal oxidation experiments in air were performed on Ti-6Al-2Sn-4Zr-2Mo (Ti-6242) with a bi-modal microstructure in the temperature range 538-649 deg.C for up to 500 hours and a-case depths were quantified using metallography. Alpha case depth followed a parabolic variation with time. Alpha case depths in excess of 10 um formed above 538 deg. C and 100 h exposures. An activation energy of 244 kJ/mol was estimated for diffusion of oxygen ... |
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| Evaluation of Suppression of Hydroprocessed Renewable Jet (HRJ) Fuel Fires with Aqueous Film Forming Foam (AFFF) |
Jul 2011 |
54 pages |
| Authors:
Steven P Wells; Brent M Pickett; Howard T Mayfield; APPLIED RESEARCH ASSOCIATES INC TYNDALL AFB FL
|
| Bio-oil derived hydroprocessed renewable jet (HRJ) fuels are alternative fuels that are being evaluated for use in United States Air Force (USAF) aircraft and support equipment and vehicles (SE&V). As with any new weapons system or other type of potential fire threat, the fire protection safety risk to the first responder must be established. This program was designed to determine if Military Specification MIL-F-24385F (MIL-SPEC) Aqueous Film Forming Foam (AFFF) ... |
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| Interpolating Spherical Harmonics for Computing Antenna Patterns |
Jul 2011 |
40 pages |
| Authors:
J Rockway; J Meloling; J C Allen; SPACE AND NAVAL WARFARE SYSTEMS COMMAND SAN DIEGO CA
|
| This report reviews spherical harmonic expansions to compute wideband antenna patterns. Some antenna patterns, such as the far-field of a ship, require lots of computer time per each frequency. Consequently, computing such a pattern across a wide frequency band at each frequency is prohibitive. Spherical harmonics offer an alternative-compute the pattern over a coarse sampling across the frequency band, interpolate the spherical harmonics, and use these harmonics to recover the ... |
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| Improving Memory for Optimization and Learning in Dynamic Environments |
Jul 2011 |
175 pages |
| Authors:
Gregory J Barlow; CARNEGIE-MELLON UNIV PITTSBURGH PA ROBOTICS INST
|
| Many problems considered in optimization and artificial intelligence research are static: information about the problem is known a priori, and little to no uncertainty about this information is presumed to exist. Most real problems, however, are dynamic: information about the problem is released over time, uncertain events may occur, or the requirements of the problem may change as time passes. One technique for improving optimization and learning in dynamic environments ... |
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| Hotline Complaint Regarding A Defense Contract Audit Agency Employee Conducting Private For-Profit Tax Business Activity on Government Time and Using Government Equipment |
28 JUN 2011 |
26 pages |
| Authors:
INSPECTOR GENERAL DEPT OF DEFENSE ARLINGTON VA
|
| We conducted this review to determine whether the complainant?s allegation concerning an employee conducting private for-profit tax business activity on Government time and using Government equipment could be substantiated. The complainant, who is anonymous, specifically alleged that: The employee was regularly heard talking to clients on the phone; and the employee was using a Government fax machine to send and receive client documents. |
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| Characterizing Cyclostationary Features of Digital Modulated Signals with Empirical Measurements using Spectral Correlation Function |
JUN 2011 |
107 pages |
| Authors:
Mujun Song; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING AND MANAGEMENT
|
| Signal detection is widely used in many applications. Some examples include Cognitive Radio (CR) and military intelligence. CRs use signal detection to sense spectral occupancy. Without guaranteed signal detection, a CR cannot reliably perform its role. Similarly, signal detection is the first step for garnering an opponent's information. Wireless signal detection can be performed using many different techniques. Some of the most popular include matched filters, energy detectors (which use ... |
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| Comparing the Capabilities and Performance of the Ultra High Frequency Follow-On System With the Mobile User Objective System |
JUN 2011 |
71 pages |
| Authors:
Christopher K. Matassa; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| The Mobile User Objective System (MUOS) is the DoD's next generation military Ultra High Frequency (UHF) Satellite Communication (SATCOM) system being designed to augment and eventually replace the currently oversubscribed UHF Follow-On (UFO) System. MUOS adapts a commercial third generation (3G) Wideband Code Division Multiple Access (WCDMA) cellular phone network architecture and combines it with geosynchronous satellites (in place of cell towers) with the goal of providing a more capable ... |
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| Simulation-Based Acceptance Testing for Unmanned Ground Vehicles |
12 May 2011 |
24 pages |
| Authors:
Amir Sadrpour; Jionghua Jin; A G Ulsoy; Hyo J Lee; MICHIGAN UNIV ANN ARBOR DEPT OF INDUSTRIAL AND OPERATIONS ENGINEERING
|
| Acceptance testing is considered a final stage of validation, and performing physical acceptance tests of an unmanned ground vehicle (UGV) can be expensive and time-consuming. Therefore, this paper discusses simulation-based acceptance testing and failure analysis for UGVs, which can be potentially used as a complementary tool in the design of efficient physical acceptance tests for reducing the testing time and cost for UGV products. In this paper, both dynamic and ... |
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| An Agile Systems Engineering Process: The Missing Link? |
May 2011 |
6 pages |
| Authors:
Matthew R Kennedy; David A Umphress; DEFENSE ACQUISITION UNIV FT BELVOIR VA
|
| Today's systems are increasingly threatened by unanticipated change arising from volatility in user requirements, Information Technology (IT) refresh rates, and responses to security vulnerabilities. With the rapidly changing world of IT, long static development cycles of a Software Intensive System (SIS), a system in which software represents the largest segment in one or more of the following criteria: system development cost, system development risk, system functionality, or development time [1] ... |
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| A phase-field description of dynamic brittle fracture |
May 2011 |
42 pages |
| Authors:
M J Borden; C V Verhoosel; M A Scott; T J Hughes; C M Landis; TEXAS UNIV AT AUSTIN INST FOR COMPUTATIONAL ENGINEERING AND SCIENCES
|
| In contrast to discrete descriptions of fracture, phase-field descriptions do not require numerical tracking of discontinuities in the displacement field. This greatly reduces implementation complexity. In this work we extend a phase-field model for quasi-static brittle fracture to the dynamic case. We introduce a phasefield approximation to the Lagrangian for discrete fracture problems and derive the coupled system of equations that govern the motion of the body and evolution of ... |
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| A Simulation and Optimization Methodology for Reliability of Vehicle Fleets |
13 Apr 2011 |
44 pages |
| Authors:
Zissimos P Mourelatos; Jing Li; Vijitashwa Pandey; Amandeep Singh; Matthew Castanier; David Lamb; ARMY TANK AUTOMOTIVE RESEARCH DEVELOPMENT AND ENGINEERING CENTER WARREN MI
|
| Overview of the briefing charts: what is reliability? Basics of reliability ethods for repairable and non-repairable systems. Estimation of PDF of Time Between Failures (TBF) using limited, censored data. |
|
| The Path of the Blind Watchmaker: A Model of Evolution |
06 APR 2011 |
152 pages |
| Authors:
Andrew A. Poggio; CALIFORNIA UNIV BERKELEY DEPT OF ELECTRICAL ENGINEERING AND COMPUTER SCIENCE
|
| Evolution has been described by Dawkins as a blind watchmaker due to its being unconscious and random but selective and able to produce complex forms. Evolution from an early, primitive organism (the Last Universal Common Ancestor of all life, LUCA) to Homo sapiens is the most dramatic biological process that has taken place on Earth and knowledge of it is important to understanding many aspects of biology including disease prevention ... |
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| Thermal-Work Strain during Marine Rifle Squad Operations in Afghanistan (March 2010) |
FEB 2011 |
39 pages |
| Authors:
Mark J. Buller; Alexander P. Welles; Jeffrey Stower; Carl Desantis; Lee Margolis; Anthony J. Karis; Demetri Economos; Reed W. Hoyt; Mark W. Richter; ARMY RESEARCH INST OF ENVIRONMENTAL MEDICINE NATICK MA
|
| The United States Marine Corps (USMC) Program Manager Marine Expeditionary Rifle Squad (PM MERS) has conducted a series of in-theater equipment surveys and analyses with Regimental Combat Teams (RCT) stationed in Iraq and Afghanistan. Anecdotal evidence from 2007 suggested that Marines in Iraq experienced high heat strain while performing missions in full combat gear (assault loads), especially during the summer months. In conjunction with the United States Army Research Institute ... |
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| Military Airborne Training Injuries and Injury Risk Factors, Fort Bragg North Carolina, June-December 2010 |
JAN 2011 |
39 pages |
| Authors:
Joseph J. Knapik; Ryan Steelman; Kyle Hoedebecke; Tyson Grier; Bria Graham; Kevin Klug; Shawn Rankin; Stanley Proctor; Bruce H. Jones; ARMY PUBLIC HEALTH COMMAND ABERDEEN PROVING GROUND MD
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| The Military Training Task Force of the Defense Safety Oversight Council funded a project to compare injury rates between the older T-10 parachute and the newer T-11 parachute. This is a preliminary report on injury incidence and injury risk factors with the T-10 parachute. From 17 June to 3 December 2010, injury and operational data were systematically collected on all jump operations performed by the 82nd Airborne Division (Fort Bragg, ... |
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| A Simulation and Optimization Methodology for Reliability of Vehicle Fleets |
Jan 2011 |
25 pages |
| Authors:
Zissimos P Mourelatos; Jing Li; Vijitashwa Pandey; Amandeep Singh; Matthew Castanier; David Lamb; OAKLAND UNIV ROCHESTER MI
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| Understanding reliability is critical in design, maintenance and durability analysis of engineering systems. A reliability simulation methodology is presented in this paper for vehicle fleets using limited data. The method can be used to estimate the reliability of non-repairable as well as repairable systems. It can optimally allocate, based on a target system reliability individual component reliabilities using a multi-objective optimization algorithm. The algorithm establishes a Pareto front that can ... |
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| Crafting a Usable Microkernel, Processor, and I/O System with Strict and Provable Information Flow Security |
Jan 2011 |
13 pages |
| Authors:
Mohit Tiwari; Jason K Oberg; Xun Li; Jonathan Valamehr; Timothy Levin; Ben Hardekopf; Ryan Kastner; Frederic T Chong; Timothy Sherwood; CALIFORNIA UNIV SANTA BARBARA DEPT OF COMPUTER SCIENCE
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| High assurance systems used in avionics, medical implants and cryptographic devices often rely on a small trusted base of hardware and software to manage the rest of the system. Crafting the core of such a system in a way that achieves flexibility, security, and performance requires a careful balancing act. Simple static primitives with hard partitions of space and time are easier to analyze formally, but strict approaches to the ... |
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