WorldCat Identities

U.S. Army Research Laboratory

Overview
Works: 1,847 works in 2,279 publications in 1 language and 188,384 library holdings
Genres: Conference papers and proceedings 
Classifications: TK5105.5, 004.6
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Most widely held works about U.S. Army Research Laboratory
 
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Most widely held works by U.S. Army Research Laboratory
A systems approach to the solid lubrication of foil air bearings for oil-free turbomachinery by Christopher DellaCorte( Book )

2 editions published in 2002 in English and held by 145 WorldCat member libraries worldwide

Computerized design and generation of gear drives with a localized bearing contact and a low level of transmission errors by F. L Litvin( Book )

2 editions published in 1996 in English and held by 95 WorldCat member libraries worldwide

A general approach developed for the computerized simulation of loaded gear drives is presented. In this paper the methodology used to localize the bearing contact, provide a parabolic function of transmission errors, and simulate meshing and contact of unloaded gear drives is developed. The approach developed is applied to spur and helical gears, spiral bevel gears, face-gear drives, and worm-gear drives with cylindrical worms
Effects of planetary gear ratio on mean service life by M Savage( Book )

2 editions published in 1996 in English and held by 94 WorldCat member libraries worldwide

Planetary gear transmissions are compact, high-power speed reductions which use parallel load paths. The range of possible reduction ratios is bounded from below and above by limits on the relative size of the planet gears. For a single plane transmission, the planet gear has no size at a ratio of two. As the ratio increases, so does the size of the planets relative to the sizes of the sun and ring. Which ratio is best for a planetary reduction can be resolved by studying a series of optimal designs. In this series, each design is obtained by maximizing the service life for a planetary with a fixed size, gear ratio, input speed power and materials. The planetary gear reduction service life is modeled as a function of the two-parameter Weibull distributed service lives of the bearings and gears in the reduction. Planet bearing life strongly influences the optimal reduction lives which point to an optimal planetary reduction ratio in the neighborhood of four to five
Dynamic analysis of spur gear transmissions (DANST) : PC version 3.00 user manual by Fred B Oswald( Book )

2 editions published in 1996 in English and held by 93 WorldCat member libraries worldwide

DANST is a FORTRAN computer program for static and dynamic analysis of spur gear systems. The program can be used for parametric studies to predict the static transmission error, dynamic load, tooth bending stress and other properties of spur gears as they are influenced by operating speed, torque, stiffness, damping, inertia, and tooth profile. DANST performs geometric modeling and dynamic analysis for low- or high-contact-ratio spur gears. DANST can simulate gear systems with contact ratios ranging from one to three. It was designed to be easy to use and it is extensively documented in several previous reports and by comments in the source code. This report describes installing and using a new PC version of DANST, covers input data requirements and presents examples
Improving the performance of the structure-based connectionist network for diagnosis of helicopter gearboxes by Vinay B Jammu( Book )

3 editions published between 1996 and 1997 in English and held by 93 WorldCat member libraries worldwide

A diagnostic method is introduced for helicopter gearboxes that uses knowledge of the gearbox structure and characteristics of the features' of vibration to define the influences of faults on features. The structural influences' in this method are defined based on the root mean square value of vibration obtained from a simplified lumped-mass model of the gearbox. The structural influences are then converted to fuzzy variables, to account for the approximate nature of the lumped-mass model, and used as the weights of a connectionist network. Diagnosis in this Structure-Based Connectionist Network (SBCN) is performed by propagating the abnormal vibration features through the weights of SBCN to obtain fault possibility values for each component in the gearbox. Upon occurrence of misdiagnoses, the SBCN also has the ability to improve its diagnostic performance. For this, a supervised training method is presented which adapts the weights of SBCN to minimize the number of misdiagnoses. For experimental evaluation of the SBCN, vibration data from a OH-58A helicopter gearbox collected at NASA Lewis Research Center is used. Diagnostic results indicate that the SBCN is able to diagnose about 80% of the faults without training, and is able to improve its performance to nearly 100% after training
Computerized design and analysis of face-milled, uniform tooth height, spiral bevel gear drives by F. L Litvin( Book )

3 editions published in 1996 in English and held by 90 WorldCat member libraries worldwide

Face-milled spiral bevel gears with uniform tooth height are considered. An approach is proposed for the design of low noise and localized bearing contact of such gears. The approach is based on the mismatch of contacting surfaces and permits two types of bearing contact either directed longitudinally or across the surface to be obtained. A Tooth Contact Analysis (TCA) computer program was developed. This analysis was used to determine the influence of misalignment on meshing and contact of the spiral bevel gears. A numerical example that illustrates the developed theory is provided
7th International Conference on Computer Communications and Networks : proceedings, October 12-15, 1998, Lafayette, Louisiana by International Conference on Computer Communications and Networks( Book )

5 editions published between 1998 and 2001 in English and held by 39 WorldCat member libraries worldwide

Application of autoassociative neural networks to health monitoring of the CAT 7 diesel engine by Andrew J Bayba( Book )

2 editions published in 2012 in English and held by 34 WorldCat member libraries worldwide

The original document contains color images
Modeling and design of mixed-coherence optical stacks by William Beck( Book )

2 editions published in 2012 in English and held by 33 WorldCat member libraries worldwide

Evaluation of a high resolution wind model over a complex terrain surface by Sam S Chang( Book )

2 editions published in 2009 in English and held by 33 WorldCat member libraries worldwide

A complete and comprehensive description of the high resolution wind (HRW) model is presented. The HRW model has been in development at the U.S. Army Research Laboratory, formerly U.S. Army Atmospheric Sciences Laboratory, since 1978. This model is a two-dimensional, diagnostic atmospheric surface-layer wind model with a horizontal grid spacing of the order of 100 m over a domain of about 5 by 5 km. It uses Gauss? principle of least constraint and a direct variational relaxation method to adjust an initially uniform wind field to conform with topography, mass conservation, and buoyancy forces. A distinctive feature of the model is the use of a non-orthogonal, terrain following, warped coordinate system. A valuable observational dataset of surface wind has been provided from the field study of Meteorology and Diffusion Over Non-Uniform Areas (MADONA) at Porton Down, Salisbury, England during September and October 1992. Using the MADONA data, a critical evaluation for the HRW model for 39 cases has been carried out. The results of this study are presented, indicating both the range of validity and the limitations of the HRW model
Ninth International Conference on Computer Communications and Networks : 16-18 October 2000, Las Vegas, Nevada : proceedings by International Conference on Computer Communications and Networks( Book )

4 editions published in 2000 in English and held by 28 WorldCat member libraries worldwide

The present state of amperometric nanowire sensors for chemical and biological detection by M. H Ervin( Book )

2 editions published in 2006 in English and held by 5 WorldCat member libraries worldwide

This report reviews the research in chemical sensing at the nanometer scale using amperometric detection focusing on publications from January 2004 to September 2005. The devices discussed fall into two categories: chemresistors and chemFETs. In either configuration, the number of carriers available in the channel, and hence the device's transconductance, changes as a function of analyte exposure. Devices based on inorganic nanowires (specifically limited to metal oxides and silicon), conductive organic polymer fibers, and carbon nanotubes are discussed as issues of sensitivity, selectivity, response/refresh times, etc
Theoretical investigation of H₂ combustion on [alpha]Al₂O₃ support by Jennifer Synowczynski( )

2 editions published in 2008 in English and held by 0 WorldCat member libraries worldwide

Based on Density Functional Theory Generalized Gradient Approximation (DFT-GGA) calculations, we provide a theoretical model for the effect of the catalytic support (alpha alumina oxide (alphaAl2O3)) on the dissociation of molecular hydrogen (H2), molecular oxygen (O2), hydroxyl (OH), water (H2O), and the surface diffusion of oxygen and hydrogen species along the Al2O3 (0001) surface. These processes are key to understanding the inverse spillover effect that occurs during hydrogen combustion on alumina surfaces. Our results indicate the dissociation of O2 is not thermodynamically favored on the Al2O3 surface. However, both H2 and H2O can dissociate, forming hydroxyls with oxygen atoms in the second atomic layer. Once dissociated, oxygen species can diffuse locally but encounter a large barrier to long-range surface diffusion in the absence of defects or other species. In contrast, the barrier to the long-range surface diffusion of hydrogen is modest under ideal conditions
Applying the principles of the Government Performance and Results Act to the research and development function : a case study submitted to the Office of Management and Budget by U.S. Army Research Laboratory( )

1 edition published in 1996 in English and held by 0 WorldCat member libraries worldwide

Modeling and Analysis of Adjacent Grid Point Wind Speed Profiles within and Above a Forest Canopy by Arnold Tunick( Book )

2 editions published in 1999 in English and held by 0 WorldCat member libraries worldwide

Adjacent grid point profile data from the canopy coupled to the surface layer (C-CSL) model are examined to illustrate the model's capability to represent effects of the surface boundary on wind flow. Vertical cross sections of the wind field and contours of derived momentum flux data are presented. Depictions of the vegetation morphology and terrain elevation data are also given for the areas studied. The C-CSL model provided data for an analysis of the surface layer wind flow within and above five different sections of vegetative canopy. As a result, the modeled wind speed profiles appeared to be in line with experimental observations. Momentum flux (Reynolds stress) data were calculated from the wind speed profile gradients. Within the canopy layer, the structure of the profiles of momentum flux appeared to agree well in contrast to data from two other turbulence closure models. In the layer above the forest canopy top, the structure of the momentum flux profiles were in line with experimental observations. In data-limited areas, this kind of modeling can be used to support land-based operations where the transport and diffusion of smoke, chemicals, or other toxic aerosols in complex terrain are a primary concern
ARL Intranet Analysis and Development Study by Dana L Ulery( )

1 edition published in 1999 in English and held by 0 WorldCat member libraries worldwide

We analyze the concept and practice of Intranets used in midsize and large enterprises, focusing on their use and impact within research and development (R & D) organizations. We examine the shift from the old concept of business computing to the modern concept of enterprise computing, and consider Intranets-a class of enterprise computing-relative to enterprise computing trends. By analyzing in detail some case studies selected from the literature, on-site visits, and workshop discussions, we then offer three tools to frame the critical issues and provide structure for systematically constructing strategic Intranets specific to a given organization's mission and culture. Arguing that creation of an Intranet that projects an image of a world-class organization demands no less than a world-class enterprise that is strategically enabled through information technology, we then analyze the current U.S. Army Research Laboratory (ARL) Intranet and present a three-step action plan to expedite ARL's movement toward creation of such an Intranet
A Proposed Modeling Protocol for Evaluating Information Attacks by John H Brand( )

1 edition published in 1999 in English and held by 0 WorldCat member libraries worldwide

The essence of an information attack is to alter, either by intrusion into and manipulation of a database or by deception, the scenario under which a target mind or organization evaluates and selects future courses of action. The aim is to influence the actions of the target. The method is alteration of the perceived desirability or expected payoff of specific courses of action. This alteration of the information in possession of the target can be described as alteration of the perceived reality under which the target operates. Probable success by an attacker in altering the target's perceived behavior, given a successful manipulation of the target's information, has, in the past, been subjective. A modeling protocol based on the use of game theory is proposed that may, in certain cases, allow optimization of the scenario, or reality, imposed on the target to force the choice of a desired course of action. It should also allow a quantitative estimate of the likelihood of the target's adopting a given course of action. This tool can be used to estimate friendly susceptibility to information attack
Time-Varying Electrostatic Modeling Techniques by David Hull( )

1 edition published in 1999 in English and held by 0 WorldCat member libraries worldwide

ARL developed computer models and modeling techniques based on the Method of Moments, and has used them for some time to study electrostatic fields associated with targets, terrain clutter, and sensors of interest. Recent extensions to these unique ARL capabilities allow some dynamic conditions to be modeled as a time series of quasi-static models. These new techniques have enabled us to study the extremely low-frequency (ELF) effects of rotating helicopter blades on both airborne and remote sensors. Examples show how a dynamic helicopter model can be used to compute time-varying airborne fieldmeter calibration factors for aircraft charge and atmospheric electric field measurements, and remote ELF electric fields which might be detected by passive surveillance sensors
Aviator Behavior and Performance as Affected by Aircrew Life Support and Protective Equipment by John D Waugh( )

1 edition published in 1999 in English and held by 0 WorldCat member libraries worldwide

A methodology for quantifying Army rotary wing aviator performance as influenced by aircrew life support, survival, and nuclear-biological-chemical clothing and equipment ensembles was examined in a set of experiential trials conducted in an AH-64 (Apache) combat mission simulator. The methodology was based on an aircrew evaluation procedure originally developed for use in the crew coordination training of all Army aviators. It uses a set of 13 basic qualities, each with behavioral anchors and a 7-point rating scale, and it is administered by specifically trained senior aviator evaluators. Ten crews, two aviators in each, while fully encumbered, performed three combat missions for record, representative of typical operational tasks, with one "variation" trial conducted without the over-water components of the ensemble. Measures of effectiveness and flight data, as well as stress assessment and equipment "complaints" citations, were recorded. The results indicated that the behavior-anchored scores were not sensitive enough to statistically discriminate among the independent variables of repeated measures and the variation trials even though graphically, differences were readily apparent. Attempts to apply transformations to the data, based on the aviator subjects' relative flying experience and their apparent accommodation to the trials were also statistically unsuccessful. The additional measures collected did not yield statistically significant discriminations nor did they correlate well with the evaluation score. A number of options for improving the technique are offered
Data Transfer Report - 30-mm Enhanced Alternate High-Energy Propellant Program (EAHEP): Test Fixture and Propellant Evaluation by Melvin B Ridgley( )

1 edition published in 1999 in English and held by 0 WorldCat member libraries worldwide

Measurements in support of the 30-mm Enhanced Alternate High-Energy Propellant Program (EAHEP) were taken at the Building 390 recording facility. Propellants evaluated for this series of tests were M30, U.S. Army Armament Research, Development, and Engineering Center (ARDEC) 7994, BAMO-AMMO/CL20, BAMO-AMMO/CL20/NQ, and BAMO-AMMO-RDX. This facility, the central data acquisition network for the Propulsion and Flight Division (PFD) of the U.S. Army Research Laboratory (ARL), was operated by the Experimental Ballistics Team (EBT) of the Propulsion Branch (PB). The testing was conducted in support of an ongoing Army effort to further investigate high-energy gun propellants that promise enhanced performance from existing tank and artillery systems
 
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Audience level: 0.49 (from 0.02 for 2009-2010 ... to 0.76 for Aeronautic ...)

7th International Conference on Computer Communications and Networks : proceedings, October 12-15, 1998, Lafayette, Louisiana
Alternative Names

controlled identityU.S. Army Ballistic Research Laboratory

controlled identityUnited States. Army Laboratory Command

AMSRL

ARL

army research laboratory

Army Research Laboratory (U.S.)

Australia Aeronautical Research Laboratory

Australia. Dept. of Defence. Aeronautical Research Laboratory

Estats Units d'Amèrica. Army. Research Laboratory

United States Aeronautical Research Laboratories

United States Aeronautical Research Laboratory

United States. Air Force. Aeronautical Research Laboratories

United States. Army. Research Laboratory

United States Research Laboratory

United States. Wright Air Development Division. Aeronautical Research Laboratory

US Army Research Laboratory

USA Air Force Research Division Aeronautical Research Laboratory

USARL

美国军方调查实验室

美國軍方調查實驗室

美國陸軍研究實驗室

Languages
English (81)

Covers
Ninth International Conference on Computer Communications and Networks : 16-18 October 2000, Las Vegas, Nevada : proceedings2009-2010 Assessment of the Army Research Laboratory