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Defense Technical Information Archive
Mar 24, 2018 Defense Technical Information Center
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Development of a free piston engine linear generator was investigated for use as an auxiliary power unit for a hybrid electric vehicle. The main focus of the program was to develop an efficient linear generator concept to convert the piston motion directly into electrical power. Computer modeling techniques were used to evaluate five different designs for linear generators. These designs included permanent magnet generators, reluctance generators, linear DC generators, and two and three-coil...
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Topics: DTIC Archive, Callahan, T. J., SOUTHWEST RESEARCH INST SAN ANTONIO TX TARDEC FUELS AND LUBRICANTS...
NASA Network Resource and Training Site
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This Program User's Guide discusses the Nuclear Thermal Propulsion (NTP) engine system design features and capabilities modeled in the Nuclear Engine System Simulation (NESS): Version 2.0 program (referred to as NESS throughout the remainder of this document), as well as its operation. NESS was upgraded to include many new modeling capabilities not available in the original version delivered to NASA LeRC in Dec. 1991, NESS's new features include the following: (1) an improved input format; (2)...
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Topics: NASA Technical Reports Server (NTRS), COMPUTERIZED SIMULATION, NUCLEAR ENGINE FOR ROCKET VEHICLES,...
Studies were conducted to develop appropriate space shuttle electrical power distribution and control (EPDC) subsystem simulation models and to apply the computer simulations to systems analysis of the EPDC. A previously developed software program (SYSTID) was adapted for this purpose. The following objectives were attained: (1) significant enhancement of the SYSTID time domain simulation software, (2) generation of functionally useful shuttle EPDC element models, and (3) illustrative...
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Topics: NASA Technical Reports Server (NTRS), COMPUTERIZED SIMULATION, ELECTRIC EQUIPMENT, ELECTRIC POWER...
Defense Technical Information Archive
Oct 1, 2016 Defense Technical Information Center
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This report describes an algorithm for estimating target velocity and acceleration using radar and inertial sensor measurements as inputs. In order to determine the accuracy and benefits of such an estimator, the algorithm is incorporated into a missile guidance law. Through the use of a simulation, terminal miss distances are compared with a similar missile using proportional navigation. Simulation results indicate a reduction in miss distance when such an estimate is used because of the...
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Topics: DTIC Archive, Bednar, Richard A., NAVAL WEAPONS CENTER CHINA LAKE CA, *TERMINAL GUIDANCE,...
Defense Technical Information Archive
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We have simulated the behavior of several artificial flies, interacting visually with each other. Each fly is described by a simple tracking system (Poggio and Reichardt, 1973; Land and Collett, 1974) which summarizes behavioral experiments in which individual flies fixate a target. Our main finding is that the interaction of theses implemodules gives rise to a variety of relatively complex behaviors. In particular, we observe a swarm-like behavior of a group of many artificial flies for...
Topics: DTIC Archive, Poggio, M., MASSACHUSETTS INST OF TECH CAMBRIDGE ARTIFICIAL INTELLIGENCE LAB,...
A computer model of the atmosphere has been developed that will solve a wide variety of lidar and atmospheric propagation problems. The lidar system calculations involve the prediction of path loss and lidar signal return for a variety of atmospheric conditions and lidar system configurations. The program contains a very large data base of absorption and attenuation coefficients for all of the naturally occurring gases and several gaseous pollutants such as S02, N02, NO, N20, 03, HCL, etc. The...
Topics: NASA Technical Reports Server (NTRS), ATMOSPHERIC MODELS, COMPUTERIZED SIMULATION, DATA BASES,...
The identification of amino acid residues essential for function of the hematopoietic growth factor erythropoietin has been approached by several methods, including comparisons of related sequences, immunochemical approaches, mutagenesis and computer modeling. We have reported previously that mutations within amino acids 100-109 of erythropoietin can have profound effects on the hormone's structure and/or activity and that Arg103 is especially important for function (Chern, Y., Chung, T. &...
Topics: DTIC Archive, Grodberg, Jennifer, HARVARD MEDICAL SCHOOL BOSTON MA, *HEMATOPOIETIC SYSTEM, *AMINO...
Through a variety of imbedded theoretical and actual antenna patterns, the array simulation platform (ASP) enhanced analysis of the array antenna pattern effects for the KTx (Ku-Band Transmit) service of the NDLM (NASA Data Link Module). The ASP utilizes internally stored models of the NDLM antennas and can develop the overall pattern of antenna arrays through common array calculation techniques. ASP expertly assisted in the diagnosing of element phase shifter errors during KTx testing and was...
Topics: NASA Technical Reports Server (NTRS), ANTENNA ARRAYS, ANTENNA RADIATION PATTERNS, COMPUTERIZED...
In 1990 the Chief of Naval Operations approved the transfer of the MARS class combat logistics force ships to the Military Sealift Command (MSC). Because MSC ships are manned with predominantly civilian crews, the total personnel assigned decreased from approximately 446 to 175 (135 civilian mariners and 40 military), resulting in an annual savings of $9.8 million per ship transferred. In this thesis we analyze the advantages and disadvantages of the transfer of the ships in terms of personnel...
Topics: DTIC Archive, Grosskopf, Kelly J., NAVAL POSTGRADUATE SCHOOL MONTEREY CA, *COMPUTERIZED SIMULATION,...
The integrated application of active controls (IAAC) technology to an advanced subsonic transport is reported. Supplementary technical data on the following topics are included: (1) 1990's avionics technology assessment; (2) function criticality assessment; (3) flight deck system for total control and functional features list; (4) criticality and reliability assessment of units; (5) crew procedural function task analysis; and (6) recommendations for simulation mechanization.
Topics: NASA Technical Reports Server (NTRS), ACTIVE CONTROL, AIRCRAFT CONTROL, PITCH (INCLINATION),...
The feasibility of using bulk GaAs for the fabrication of diffused junction solar cells was determined. The effects of thermal processing of GaAs was studied, and the quality of starting bulk GaAs for this purpose was assessed. These cells are to be made by open tube diffusion techniques, and are to be tested for photovoltaic response under AMO conditions.
Topics: NASA Technical Reports Server (NTRS), CZOCHRALSKI METHOD, FEASIBILITY ANALYSIS, PHOTOVOLTAIC...
This technical note presents a simple analytical method for evaluating the size of mixing zones for effluents from confined dredged material disposal areas. The method involves a simplistic two-dimensional calculation based on dispersion principles. Discussions of the applicability and limitations of the technique and a stepwise procedure for performing the required calculations are presented. Recommendations for using computer-based approaches for more complex conditions are also discussed.
Topics: DTIC Archive, MacIntyre, David F, ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS...
A 2-D boundary layer computer code developed to process data for an arbitrary number of streamlines is presented. Provisions are included for the computer code to determine either mass transfer rates necessary for an effective boundary layer displacement of zero thickness or the effective displacement thickness for a specified mass transfer-rate distribution. The computer code was developed to be compatible with other computer codes which are being modified and/or developed at the NASA-Langley...
Topics: NASA Technical Reports Server (NTRS), COMPUTERIZED SIMULATION, LININGS, TRANSONIC FLOW, WIND TUNNEL...
Monte Carlo simulations combined with sudden death testing were used to compare resultant bearing lives to the calculated hearing life and the cumulative test time and calendar time relative to sequential and censored sequential testing. A total of 30 960 virtual 50-mm bore deep-groove ball bearings were evaluated in 33 different sudden death test configurations comprising 36, 72, and 144 bearings each. Variations in both life and Weibull slope were a function of the number of bearings failed...
Topics: NASA Technical Reports Server (NTRS), BALL BEARINGS, MONTE CARLO METHOD, COMPUTERIZED SIMULATION,...
Traditionally, the military has used live simulation as a primary means of training. With the high cost of such training and the growing shortage of adequate space for its conduct, constructive simulation and, more recently, virtual simulation have become increasingly important. The convergence of Live (real people and equipment but simulated results), Virtual (Real people but simulated equipment and environment) Constructive (Simulated people, equipment & environment, stimulated by real...
Topics: DTIC Archive, MILITARY ACADEMY LIPTOVSKY MIKULAS (SLOVAKIA), *COMPUTERIZED SIMULATION, ASYMMETRIC...
This document presents the data analysis procedures proposed for use with the COMPTEL instrument aboard the Compton Gamma Ray Observatory (GRO) in the search for radiative neutrino decay from supernovae. The proposed analysis methodology is an extension of a standard procedure used by the COMPTEL team in searching for a variety of source types. We have applied the procedures to a set of simulated data to demonstrate the feasibility of the method to this project.
Topics: NASA Technical Reports Server (NTRS), COMPUTERIZED SIMULATION, EMISSION SPECTRA, ENERGY SPECTRA,...
An important question in the development of item pools for computerized adaptive tests (CATs) is whether data for calibrating items should be collected by a paper-and-pencil (P&P) or a computer administration of the items. This study evaluated the effect on adaptive scores of using a P&P calibration. The correspondence between adaptive scores obtained with computer- administered items and a P&P calibration with adaptive scores obtained with computer-administered items and a computer...
Topics: DTIC Archive, Hetter, Rebecca D, NAVY PERSONNEL RESEARCH AND DEVELOPMENT CENTER SAN DIEGO CA,...
A unified formulation of computer-aided, multi-task, decision making is presented. Strategy for the allocation of decision making responsibility between human and computer is developed. The plans of a flight management systems are studied. A model based on the queueing theory was implemented.
Topics: NASA Technical Reports Server (NTRS), DECISION MAKING, HUMAN BEINGS, MULTIPROCESSING (COMPUTERS),...
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This technical note describes a microwave circuit simulator implemented in the technical computing language, MATLAB. The simulator takes an input circuit with a known admittance matrix, performs a node swap that puts the external nodes (ports) at the upper left hand of an equivalent admittance matrix, then reduces the matrix (regardless of size) to include only the external nodes using Householder's method. The resulting 2 x 2 admittance matrix provides all the information to uniquely define...
Topics: DTIC Archive, DEL Rosario, Romeo D, ARMY RESEARCH LAB ADELPHI MD SENSORS AND ELECTRON DEVICES...
The Emergency Management Computer-Aided Trainer (EMCAT) developed by Essex Corporation or NASA and the Federal Emergency Management Administration's (FEMA) National Fire Academy (NFA) is described. It is a computer based training system for fire fighting personnel. A prototype EMCAT system was developed by NASA first using video tape images and then video disk images when the technology became available. The EMCAT system is meant to fill the training needs of the fire fighting community with...
Topics: NASA Technical Reports Server (NTRS), COMPUTER ASSISTED INSTRUCTION, COMPUTER PROGRAMS, FIRE...
Substantial progress has been made toward the goals of this research effort in the past six months. A simplified rotor model with a flexible shaft and backup bearings has been developed. The model is based upon the work of Ishii and Kirk. Parameter studies of the behavior of this model are currently being conducted. A simple rotor model which includes a flexible disk and bearings with clearance has been developed and the dynamics of the model investigated. The study consists of simulation work...
Topics: NASA Technical Reports Server (NTRS), BEARINGS, DYNAMIC STRUCTURAL ANALYSIS, FINITE ELEMENT METHOD,...
bd Systems (a subsidiary of SAIC) has developed the Simulation Package for Autonomous Rendezvous Test and ANalysis (SPARTAN), a high-fidelity on-orbit simulation featuring multiple six-degree-of-freedom (6DOF) vehicles. SPARTAN has been developed in a modular fashion in Matlab/Simulink to test next-generation automated rendezvous and docking guidance, navigation,and control algorithms for NASA's new Vision for Space Exploration. SPARTAN includes autonomous state-based mission manager algorithms...
Topics: NASA Technical Reports Server (NTRS), SIMULATION, DEGREES OF FREEDOM, ORBITAL RENDEZVOUS, MISSION...
To investigate the mechanical and other condensed phase properties of energetic materials using atomistic simulation techniques, the COMPASS force field has been expanded to include high-energy nitro functional groups. This report presents the parameterization and validation of COMPASS for nitrate esters (-ONO2). The functional forms of this force field are of the consistent force field type. The parameters were derived with an emphasis on the nonbonded parameters, which include a Lennard-Jones...
Topics: DTIC Archive, Bunte, Steven W, ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD WEAPONS AND MATERIALS...
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Accurate ocean forecast requires and combines knowledge in physics, mathematics, computer sciences, drawing greatest advantage of the new technologies for access, analysis and distribution of the data. We will describe NCOM_OS, a portable, relocatable, and user-friendly prediction system based on the Naval Coastal Ocean Model (NCOM). The system has been developed and routinely applied in support of naval operation. With this product, analysis and prediction can be provided for any part of the...
Topics: DTIC Archive, Peggion, Germania, NEW ORLEANS UNIV LA DEPT OF PHYSICS, *COMPUTERIZED SIMULATION,...
The Army has articulated a vision in which simulations will support C4ISR systems through the integration of simulation infrastructure into the Defense Information Infrastructure Common Operating Environment (DII COE) software architecture. Identification of a specific simulation infrastructure product set is the key to developing the technical steps required to achieve this vision. Integrating simulation into the DII COE in a systematic fashion requires the following: (1) reuse by the...
Topics: DTIC Archive, Sprinkle, Ronald B, MITRE CORP MCLEAN VA WASHINGTON C3I DIV, *COMPUTERIZED...
The objective was to develop a computerized adaptive pilot model for the computer model of the research aircraft, the Harrier II AV-8B V/STOL with special emphasis on propulsion control. In fact, two versions of the adaptive pilot are given. The first, simply called the Adaptive Control Model (ACM) of a pilot includes a parameter estimation algorithm for the parameters of the aircraft and an adaption scheme based on the root locus of the poles of the pilot controlled aircraft. The second,...
Topics: NASA Technical Reports Server (NTRS), ADAPTIVE CONTROL, COMPUTERIZED SIMULATION, FLIGHT CONTROL,...
Theory and numerical results are given for a program simulating two dimensional granular flow (1) between two infinite, counter-moving, parallel, roughened walls, and (2) for an infinitely wide slider. Each granule is simulated by a central repulsive force field ratcheted with force restitution factor to introduce dissipation. Transmission of angular momentum between particles occurs via Coulomb friction. The effect of granular hardness is explored. Gaps from 7 to 28 particle diameters are...
Topics: NASA Technical Reports Server (NTRS), COMPUTERIZED SIMULATION, FLOW VISUALIZATION, GRANULAR...
This presentation discusses Columbia World Class Supercomputer which is one of the world's fastest supercomputers providing 61 TFLOPs (10/20/04). Conceived, designed, built, and deployed in just 120 days. A 20-node supercomputer built on proven 512-processor nodes. The largest SGI system in the world with over 10,000 Intel Itanium 2 processors and provides the largest node size incorporating commodity parts (512) and the largest shared-memory environment (2048) with 88% efficiency tops the...
Topics: NASA Technical Reports Server (NTRS), COMPUTER SYSTEMS SIMULATION, SUPERCOMPUTERS, COMPUTER SYSTEMS...
Defense Technical Information Archive
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This paper specifies the Modeling and Simulation Data Engineering Technical Framework (M&S DE-TF). Within the Modeling and Simulation Common Technical Framework 1, the M&S DE-TF is: the formal vehicle for promulgating and enforcing data standards, and a template for using data standards to create, manage, and deliver data .
Topics: DTIC Archive, Augins, Jim, DEFENSE MODELING AND SIMULATION OFFICE ALEXANDRIA VA, *COMPUTERIZED...
We develop a simulation model to aid in identifying and evaluating promising alternatives to achieve improvements in weapon system-level availability when outsourcing logistics services for system components. Two outcomes are valued: improvements in average operational availability for the weapon system, and reductions in the probability that operational availability of the weapon system falls below a given planning threshold (readiness risk). In practice, these outcomes must be obtained...
Topics: DTIC Archive, NAVAL POSTGRADUATE SCHOOL MONTEREY CA GRADUATE SCHOOL OF BUSINESS AND PUBLIC POLICY,...
Over the past several years the INtegral Theory of Impact has been developed by A.R.A.P. It is already proving to be a useful tool in the design of armor and penetrators. The theory contains the essential physics of the impact process, satisfies all the global conservation equations and is contained in a computer code which is simple and inexpensive to operate. The integral theory requires far less empirical information than some models and avoids the high cost and complexity of multi-element...
Topics: DTIC Archive, Swanson,Claude V, AERONAUTICAL RESEARCH ASSOCIATES OF PRINCETON INC NJ, *COMPUTERIZED...
Over the past several years the INtegral Theory of Impact has been developed by A.R.A.P. It is already proving to be a useful tool in the design of armor and penetrators. The theory contains the essential physics of the impact process, satisfies all the global conservation equations and is contained in a computer code which is simple and inexpensive to operate. The integral theory requires far less empirical information than some models and avoids the high cost and complexity of multi-element...
Topics: DTIC Archive, Swanson,Claude V, AERONAUTICAL RESEARCH ASSOCIATES OF PRINCETON INC NJ, *COMPUTERIZED...
Over the past several years the INtegral Theory of Impact has been developed by A.R.A.P. It is already proving to be a useful tool in the design of armor and penetrators. The theory contains the essential physics of the impact process, satisfies all the global conservation equations and is contained in a computer code which is simple and inexpensive to operate. The integral theory requires far less empirical information than some models and avoids the high cost and complexity of multi-element...
Topics: DTIC Archive, Swanson,Claude V, AERONAUTICAL RESEARCH ASSOCIATES OF PRINCETON INC NJ, *COMPUTERIZED...
Defense Technical Information Archive
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A magnetic tape transport system employing stepper motors has been investigated and developed. Before the investigation of the system, a mathematical model for a four-phase permanent magnet stepper motor was developed and its behavior studied by computer simulation. At the beginning, a system was proposed employing a single tension spring between the take-up motor and its reel to maintain a tape tension. From computer simulation, it was found that such a scheme does not regulate tape tension...
Topics: DTIC Archive, Tsavdaris, Sotirios A, NAVAL POSTGRADUATE SCHOOL MONTEREY CA, *COMPUTER AIDED DESIGN,...
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Heat transfer to the barrel wall of a 155mm howitzer was calculated as part of an interior ballistics calculation with Gough's two phase flow code NOVA. The heat transfer coefficient between the core flow and the barrel wall was estimated by reference to a turbulent pipe flow correlation. The unsteady conduction in the wall was solved for the entire length of the chamber and tube.
Topics: DTIC Archive, Nelson, Carl W, ARMY BALLISTIC RESEARCH LAB ABERDEEN PROVING GROUND MD, *HEAT...
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Heat transfer to the barrel wall of a 155mm howitzer was calculated as part of an interior ballistics calculation with Gough's two phase flow code NOVA. The heat transfer coefficient between the core flow and the barrel wall was estimated by reference to a turbulent pipe flow correlation. The unsteady conduction in the wall was solved for the entire length of the chamber and tube.
Topics: DTIC Archive, Nelson, Carl W, ARMY BALLISTIC RESEARCH LAB ABERDEEN PROVING GROUND MD, *HEAT...
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The governing partial differential equations and constitutive relations are presented for the two-phase, axisymmetric, turbulent flow in a gun tube with a rotating projectile. The formulation included the following constitutive models: Noble-Abel gas equation of state, molecular viscosity and thermal conductivity, turbulent viscosity and length scale, intergranular stress relation, interphase drag and heat transfer relations, and a burning rate correlation for solit phase combustion. The...
Topics: DTIC Archive, Gibeling, Howard J, SCIENTIFIC RESEARCH ASSOCIATES INC GLASTONBURY CT, *COMPUTERIZED...
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The governing partial differential equations and constitutive relations are presented for the two-phase, axisymmetric, turbulent flow in a gun tube with a rotating projectile. The formulation included the following constitutive models: Noble-Abel gas equation of state, molecular viscosity and thermal conductivity, turbulent viscosity and length scale, intergranular stress relation, interphase drag and heat transfer relations, and a burning rate correlation for solit phase combustion. The...
Topics: DTIC Archive, Gibeling, Howard J, SCIENTIFIC RESEARCH ASSOCIATES INC GLASTONBURY CT, *COMPUTERIZED...
Defense Technical Information Archive
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The governing partial differential equations and constitutive relations are presented for the two-phase, axisymmetric, turbulent flow in a gun tube with a rotating projectile. The formulation included the following constitutive models: Noble-Abel gas equation of state, molecular viscosity and thermal conductivity, turbulent viscosity and length scale, intergranular stress relation, interphase drag and heat transfer relations, and a burning rate correlation for solit phase combustion. The...
Topics: DTIC Archive, Gibeling, Howard J, SCIENTIFIC RESEARCH ASSOCIATES INC GLASTONBURY CT, *COMPUTERIZED...
Defense Technical Information Archive
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The governing partial differential equations and constitutive relations are presented for the two-phase, axisymmetric, turbulent flow in a gun tube with a rotating projectile. The formulation included the following constitutive models: Noble-Abel gas equation of state, molecular viscosity and thermal conductivity, turbulent viscosity and length scale, intergranular stress relation, interphase drag and heat transfer relations, and a burning rate correlation for solit phase combustion. The...
Topics: DTIC Archive, Gibeling, Howard J, SCIENTIFIC RESEARCH ASSOCIATES INC GLASTONBURY CT, *COMPUTERIZED...
During the past decade, several unsteady, two-phase flow interior ballistic models have been developed which include treatment of ignition and flamespread through the propellant bed. While all such models were originally formulated under the simplifying assumption of one-dimensional flow, efforts are now underway to provide multi-dimensional representations, as well as to improve the descriptions of constitutive physical process. One important step, however, along the road to a...
Topics: DTIC Archive, Minor, Thomas C, ARMY BALLISTIC RESEARCH LAB ABERDEEN PROVING GROUND MD, *IGNITION,...
During the past decade, several unsteady, two-phase flow interior ballistic models have been developed which include treatment of ignition and flamespread through the propellant bed. While all such models were originally formulated under the simplifying assumption of one-dimensional flow, efforts are now underway to provide multi-dimensional representations, as well as to improve the descriptions of constitutive physical process. One important step, however, along the road to a...
Topics: DTIC Archive, Minor, Thomas C, ARMY BALLISTIC RESEARCH LAB ABERDEEN PROVING GROUND MD, *IGNITION,...
During the past decade, several unsteady, two-phase flow interior ballistic models have been developed which include treatment of ignition and flamespread through the propellant bed. While all such models were originally formulated under the simplifying assumption of one-dimensional flow, efforts are now underway to provide multi-dimensional representations, as well as to improve the descriptions of constitutive physical process. One important step, however, along the road to a...
Topics: DTIC Archive, Minor, Thomas C, ARMY BALLISTIC RESEARCH LAB ABERDEEN PROVING GROUND MD, *IGNITION,...
During the past decade, several unsteady, two-phase flow interior ballistic models have been developed which include treatment of ignition and flamespread through the propellant bed. While all such models were originally formulated under the simplifying assumption of one-dimensional flow, efforts are now underway to provide multi-dimensional representations, as well as to improve the descriptions of constitutive physical process. One important step, however, along the road to a...
Topics: DTIC Archive, Minor, Thomas C, ARMY BALLISTIC RESEARCH LAB ABERDEEN PROVING GROUND MD, *IGNITION,...
During the past decade, several unsteady, two-phase flow interior ballistic models have been developed which include treatment of ignition and flamespread through the propellant bed. While all such models were originally formulated under the simplifying assumption of one-dimensional flow, efforts are now underway to provide multi-dimensional representations, as well as to improve the descriptions of constitutive physical process. One important step, however, along the road to a...
Topics: DTIC Archive, Minor, Thomas C, ARMY BALLISTIC RESEARCH LAB ABERDEEN PROVING GROUND MD, *IGNITION,...
During the past decade, several unsteady, two-phase flow interior ballistic models have been developed which include treatment of ignition and flamespread through the propellant bed. While all such models were originally formulated under the simplifying assumption of one-dimensional flow, efforts are now underway to provide multi-dimensional representations, as well as to improve the descriptions of constitutive physical process. One important step, however, along the road to a...
Topics: DTIC Archive, Minor, Thomas C, ARMY BALLISTIC RESEARCH LAB ABERDEEN PROVING GROUND MD, *IGNITION,...
The residual stresses in an autofrettaged tube of compressible material are obtained by a new finite-difference approach. The tube is assumed to obey the von Mises' yield criterion, the Prandtl-Reuss flow theory and the isotropic-hardening rule. In order to test the accuracy of the computer program, a convergence study for a nearly incompressible tube has been made and compared with the exact solution as well as the simulated results for residual stresses in an incompressible tube.
Topics: DTIC Archive, Chen, P C, ARMY ARMAMENT RESEARCH AND DEVELOPMENT CENTER WATERVLIET NY LARGE CALIBER...
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Stream water quality modeling is applied to a practical case showing impact analysis regarding future alternative land use. (Author)
Topics: DTIC Archive, Willey,R G, HYDROLOGIC ENGINEERING CENTER DAVIS CA, *WATER QUALITY, MATHEMATICAL...
We present two new models and their exact analysis for the problem of two processors running the Time Warp distributed simulation protocol. Our first model addresses the queueing of messages at each processor while the second model adds costs for rollback and state saving. Both models provide insight into the operation of freerunning systems synchronized by rollback. Discrete event simulation, Time warp, Parallel processing, Distributed processing, Simulation, Optimistic simulation, Rollback,...
Topics: DTIC Archive, Felderman, Robert E, UNIVERSITY OF SOUTHERN CALIFORNIA MARINA DEL REY INFORMATION...
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This thesis concentrates on developing a spreadable model that can be used by Marine logisticians in computing sustainment requirements and the resulting tactical motor transport lift requirements necessary to keep a notional sized maneuver element supported on a daily basis in the Marine Corps projected maneuver warfare environment. Sustainment computations are limited to resupplying the maneuver element with food, water, fuel, and ammunition. Using an "add-in" simulation package the...
Topics: DTIC Archive, Allen, Scott A., NAVAL POSTGRADUATE SCHOOL MONTEREY CA, *COMPUTERIZED SIMULATION,...
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To fully utilize scarce airlift resources requires effective airlift planning, a more capable air mobility system, and highly mobile forces. Presently, the Turkish Air Mobility Command's (TAMC) airlift planning is performed manually. The aim of this research is to provide a tactical mobility model which is user friendly and flexible so the user is able to change the inputs, and evaluate the situation with the projected data for an operational plan. Thus, the users can analyze their system by...
Topics: DTIC Archive, Topcuoglu, Huseyin, AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH, *AIRLIFT...
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After a literature research, the development of the TNO-PML Cook-off test started in 1987. During the years of development, many modifications were made to the test object. In this configuration, test data can be obtained to verify the thermal/chemical Cook-off computer models. Because the general interest is more focused on the level of severity in a Cook-off event, the development of the TNO-PML Cook-off test went in the same direction. Detonation and deflagration to detonation transition...
Topics: DTIC Archive, Scholtes, J. H., PRINS MAURITS LABORATORIUM TNO RIJSWIJK (NETHERLANDS), *STRAIN RATE,...
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The purpose of this research project was to design an interactive computer ToolBook that illustrated and analyzed the Battle of Gettysburg. The ToolBook identifies the principal actors, the objectives they were trying to attain, what influenced their decisions, and examines the battle from both sides. It focuses on the movement and employment of infantry and cavalry troops and presents a pictorial of the changing battle. It analyzes the advantages, disadvantages, strengths and weaknesses of the...
Topics: DTIC Archive, Lambert, Marie, AIR COMMAND AND STAFF COLL MAXWELL AFB AL, *BATTLES, *COMPUTERIZED...
This report details the investigation of VHF radio direction finding (DF) and the effects of multipath propagation for terrestrial paths. For this investigation, an eight channel DF system was used to make field measurements of a transmitter as it was slowly moved along a designated route. This allowed the fine scale effects of multipath on the measured signal bearing and power to be observed - effects which had been previously observed as being noise like in nature. Computer modeling was also...
Topics: DTIC Archive, Read, William J., DEFENCE RESEARCH ESTABLISHMENT OTTAWA (ONTARIO), *VERY HIGH...
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A complete description concerning the interface region of a parallel radial face seal has been conducted both experimentally and analytically. Analytical predictions stem from a FORTRAN IV computer program designed such that density and viscosity variation with temperature can be simulated. The equations of motion were solved on an incremental basis to yield a 'closed form, finite difference' solution. For comparison purposes, predictions assuming non- temperature dependent fluid properties are...
Topics: DTIC Archive, Swafford, Timothy W, TENNESSEE UNIV KNOXVILLE DEPT OF MECHANICAL AEROSPACE AND...
This research product provides functional specifications for reconfigurable simulators to support research on future main battle tanks in the Close Combat Test Bed (CCTB). A key factor in maximizing the use of networked simulation for research is the flexibility or reconfigurability of the vehicle simulator. Efforts to enhance human performance or to assess alternative embedded training systems, for example, must begin with descriptions of the proposed simulation functionality. The...
Topics: DTIC Archive, Lawless, Michael T, MICRO ANALYSIS AND DESIGN BOULDER CO, *COMPUTERIZED SIMULATION,...
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The main objectives of the research were to develop realistic model for an individual thunderstorm cell, and to investigate the relationships between the large-scale meteorological fields and cumulus cloud ensembles so that the parameterization for cumulus clouds in a global circulation model may be improved on a more scientifically sound basis.
Topics: DTIC Archive, Ogura, Y, ILLINOIS UNIV AT URBANA LAB FOR ATMOSPHERIC RESEARCH, *CLOUD PHYSICS,...
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Coherent optical adaptive techniques are designed to overcome degradations experienced by optical beams propagating in media with fixed or time-varying distortions. This report presents results from the calibration phase of an experimental eighteen-element, self-adaptive optical phased array. Initial tests on a turbulent, outdoor propagation range are also presented. Computer simulation studies have demonstrated the advantages of a divider-AGC network and have detailed the theoretical system...
Topics: DTIC Archive, Bridges, W B, HUGHES RESEARCH LABS MALIBU CA, *OPTICAL RADAR, *PHASED ARRAYS,...
Chemical, Biological, Radiological-Nuclear and Explosives (CBRNE) pose a real threat to Canadians and indeed to North Americans. The events of September 11th, 2001 prove that we are not immune to terrorist attacks, and that our lives and psychological wellbeing can be destroyed in an instant when one of these attacks is executed on Canadian and/or North American soil. The Chemical, Biological, Radiological-Nuclear and Explosives Research and Technology Initiative (CRTI) has been conceived to...
Topics: DTIC Archive, Hasham,Zubin, 3DInternet Inc Calgary, Alberta Canada, first responsers, training,...
The pressure amplitude and phase distribution along the interface between a tapered fluid layer and an underlying fast fluid bottom were investigated theoretically. Two computer models, both based on the method of images, were designed: WEDGE 1 assumes that the source is at a finite distance from the apex of the wedge, and WEDGE 2 assumes an infinite distance. The pressure amplitude along the interface rapidly falls off for distances closer to the apex than the distance at which adiabatic mode...
Topics: DTIC Archive, Coppens,Alan B, NAVAL POSTGRADUATE SCHOOL MONTEREY CA, *COMPUTERIZED SIMULATION,...
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In many cases, a simulation study may be viewed as an experimental situation in which a number of factors (independent variables) are to be investigated. However, standard experimental design techniques often require more simulation runs than are available to the simulation user. In general, the primary problem of experimental design in simulation can be succinctly summarized as too many factors and too few runs. A discussion of this problem is presented in this report. Three possible two-stage...
Topics: DTIC Archive, Smith, Dennis E., DESMATICS INC STATE COLLEGE PA, *COMPUTERIZED SIMULATION,...
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This report illustrates estimates of support investment costs and recurring operations and support costs through a Model for estimating Aircraft Cost of Ownership (MACO), which also provides a framework for future research. MACO is an outgrowth of an earlier evaluation of the strengths and weaknesses of the most widely used aircraft life cycle cost models. It combines new algorithms for major, maintenance-related costs with formulas drawn from existing models for other cost elements. MACO...
Topics: DTIC Archive, Marks,Kenneth E, RAND CORP SANTA MONICA CA, *AIRCRAFT, *COST MODELS, *LIFE CYCLE...
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The development of a microprocessor system simulation that would accurately portray the operation of the system at a very fine level of detail was studied. This optimization in the area of fidelity was broken into three tasks. A preprocessor program was written to improve the operator interface to an existing simulation driver program. An existing microprocessor simulation, designed to run under the simulation driver program, was extensively modified to reflect actual machine level operations...
Topics: DTIC Archive, Landrum,Earnest Taylor , Jr, AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH,...
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Automated metal parts production facilities are complex because they are integrated with automated material handling systems, centralized chip transport systems, and automatic gaging; therefore, it is more difficult to predict monthly production throughput. The primary objective of this program is to develop a methodology to simulate production line behavior through computer modeling. The need to develop more reliable input data (such as MTBF and MTTR) is recognized and methodology to calculate...
Topics: DTIC Archive, Menke, William, ARMY ARMAMENT RESEARCH AND DEVELOPMENT CENTER DOVER NJ LARGE CALIBER...
The objectives of the seminar were: (1) to bring together developers, users, and potential users of two-dimensional mathematical models to develop a continuing dialogue concerning applications experience, problem identification, research goals, model evaluation, operational problems and model limitations; (2) to make researchers working in the areas of riverine and flood plain simulation aware of recent advances in coastal and estuarine modeling; and, (3) to examine mechanisms for transferring...
Topics: DTIC Archive, MacArthur,Robert C, HYDROLOGIC ENGINEERING CENTER DAVIS CA, *MATHEMATICAL MODELS,...
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A system was developed to simulate the overland flow of rainfall runoff in a microgeometric model of the landscape. The landscape model was developed from normally available materials by means of a geographic data-handling system. The water flow model provides both direct rainfall and grid-to-grid flo components for every grid on the landscape. The size of the grid, the time increment for analysis, and the rainfall intensity are adjustable by the user. The surface flow is followed in an...
Topics: DTIC Archive, LaGarde,Victor E, ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS...
This work consists of the development of the six degree of freedom non-linear model of a sea launched generic bank-to-turn cruise missile attacking a medium sized combatant ship. Two guidance and control schemes are compared in the terminal phase. The first, or baseline guidance scheme (pop out maneuver), uses a 50-foot altitude hold for an ingress phase, followed by a pop out maneuver, and then an attack phase which uses proportional navigation in elevation and azimuth planes along with...
Topics: DTIC Archive, Watterson,Kent B, NAVAL POSTGRADUATE SCHOOL MONTEREY CA, *Antiship missiles, *Cruise...
The functional stress intensity approach is presented for a partially autofrettaged, thick-walled cylinder. This approach is a combination of a series of methods developed for the computation of stress intensity factors for multiple-radial cracks emanating from the inner or the outer surface of a hollow cylinder. The numerical method is mainly based on the finite element method using 12-node quadrilateral, isoparametric elements with singular elements around a crack tip. The difficulty due to...
Topics: DTIC Archive, Pu, S L, ARMY ARMAMENT RESEARCH AND DEVELOPMENT CENTER WATERVLIET NY LARGE CALIBER...
A composite scenario was used to conduct a comprehensive task analysis of the UH-60 helicopter mission. This analysis used a top-down approach to identify the phases, functions, and tasks of the mission. Nine phases, 34 segments, 48 functions, and 138 tasks were identified. The crew-member performing each function was identified, and estimates of the sensory, cognitive, and psychomotor workload associated with the tasks were derived. Estimates of the task times also were derived. The...
Topics: DTIC Archive, Bierbaum, Carl R, ANACAPA SCIENCES INC FORT RUCKER AL, *HELICOPTERS, *MISSIONS,...
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This is the user manual for computer simulation model MILHY3. The volume should contain all the information a potential user requires to establish the data sets and run MILHY3. It provides detailed program information and the computer code. A basic review of the MILHY suite is provided and some guidelines on the selection of process are included. It contains a number of hydrological and model control procedures. Each of these is contained within the program implementation in a separate...
Topics: DTIC Archive, Baird, L, BRISTOL UNIV (UNITED KINGDOM), *FLOODS, *COMPUTERIZED SIMULATION,...
This study investigated what the potential cash flow condition of the Reparable Support Division of the Air Force Stock Fund might be after final implementation of the procedures outlined in Defense Management Review Decision 904, Stock Funding Depot Level Reparables. The operation of the future Reparable Support Division was modelled using the General Purpose Simulation Software (GPSS/H) package and future cash flow conditions were projected through use of this model. Recommendations were then...
Topics: DTIC Archive, Elliot, Deborah A, AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH, *AIR FORCE,...
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This paper presents techniques that actively exploit chaotic behavior to accomplish otherwise-impossible control tasks. The state space is mapped by numerical integration at different system parameter values and trajectory segments from several of these maps are automatically combined into a path between the desired system states. A fine-grained search and high computational accuracy are required to locate appropriate trajectory segments, piece them together and cause the system to follow this...
Topics: DTIC Archive, Bradley, Elizabeth, MASSACHUSETTS INST OF TECH CAMBRIDGE ARTIFICIAL INTELLIGENCE LAB,...
Within a defined domain, geophysical phenomena often are characterized by smooth continuous power spectral densities having a negative power law slope. Frequently, Fourier transform analysis has been employed to generate synthetic scenes from pseudorandom arrays by passing the stochastic data through a Fourier filter having a desired correlation structure and power spectral dependency. This report examines the possibility of producing synthetic structure by invoking autoregression analysis as...
Topics: DTIC Archive, Brown, James H, PHILLIPS LAB HANSCOM AFB MA, *ATMOSPHERE MODELS, *ATMOSPHERIC...
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An invariable characteristic of any successful entity is its ability to effectively and efficiently manage its corporate information. The benefits gained as a result of maintaining such a resource have been echoed repeatedly through the years. Codifying the information and lessons learned from the past allow for the potential cost and time savings of the future. Towards this end, the Ballistic Vulnerability Lethality Division (BVLD) of the U.S. Army Research laboratory (ARL) bas adopted a...
Topics: DTIC Archive, Hanratty, Timothy P., ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD, *ARMY RESEARCH,...
Topics: DTIC Archive, McKillip, Robert M., Jr., CONTINUUM DYNAMICS INC PRINCETON NJ, *VIBRATION,...
Electrochemical impedance spectroscopy (E.I.S.) techniques can provide information about the condition of protective coatings on steel marine structures. Currently, an expert is required to interpret the data produced from an E.I.S. measurement, classifying the coating as 'good' or 'poor' or identifying the data as 'bad.' This limits the use of E.I.S. techniques to experienced operators. If the E.I.S. technique is to be used for production by inexperienced operators, measurements must be...
Topics: DTIC Archive, Hack, Harvey P., NAVAL SURFACE WARFARE CENTER CARDEROCK DIV BETHESDA MD, *NEURAL...
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As new and innovative methods are developed for detecting aerosolized biological weapons, these detectors must also be tested for accuracy, sensitivity and reliability. It is essential that these biological triggers are thoroughly tested before progressing to field testing as field trials are costly and time consuming. A method for testing a Fluorescent Aerodynamic Particle Sizer (FL/APS), a biological trigger detector, with rapid turn around time was developed using a small, 12 m3 aerosol test...
Topics: DTIC Archive, Semler, D D, DYCOR TECHNOLOGIES LTD EDMONTON, *BIOLOGICAL WARFARE, *BIOLOGICAL...
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The UCLA National Center for Research on Evaluation, Standards, and Student Testing (CRESST) designed and developed a knowledge mapping authoring system intended to be simple and user-friendly, requiring a minimal number of clicks to navigate, but highly functional. The authoring system is intended to allow a diverse set of users to create, modify, adapt, and reuse knowledge mapping tasks. Various scoring options provide information on student performance on different dimensions and at...
Topics: DTIC Archive, Chung, Gregory K, CALIFORNIA UNIV LOS ANGELES CENTER FOR THE STUDY OF EVALUATION,...
Unmanned aerial vehicle and smart munition systems need robust, real-time path generation and guidance systems to avoid terrain obstructions, navigate in hazardous weather conditions, and react to mobile threats such as radar, jammers, and unfriendly aircraft. In Phase 1 of this STTR project, real-time path planning and trajectory generation techniques for two dimensional flight were developed and demonstrated in software simulation. In Phase 2 these algorithms were refined, extended and were...
Topics: DTIC Archive, Larsen, Michael, *COMPUTERIZED SIMULATION, *REAL TIME, *TRAJECTORIES, COMPUTER...
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The authors have designed and fabricated infrared filters for use at wavelengths greater than or equal to 15 microns. Unlike conventional dielectric filters used at short wavelengths, these are made from stacked metal grids spaced at a very small fraction of the performance wavelengths. The individual lattice layers are gold, the spacers are polyimide, and they are assembled using integrated circuit processing techniques, They resemble some metallic photonic band-gap structures. The authors...
Topics: DTIC Archive, Smith, Howard A, NAVAL RESEARCH LAB WASHINGTON DC, *GRIDS, *FABRICATION,...
The DoD sets forth an objective to employ an active cyber defense capability to prevent intrusions onto DoD networks and systems. Intrusion Detection Systems (IDS) are a critical part of network defense architectures, but their alerts can be difficult to manage. This research applies Queuing Theory to the management of IDS alerts, seeking to answer how analysts and priority schemes effect alert processing performance. To characterize the effect of these two variables on queue wait times, a...
Topics: DTIC Archive, AIR FORCE INSTITUTE OF TECHNOLOGY WRIGHT-PATTERSON AFB OH GRADUATE SCHOOL OF...
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This paper will present a validation of the turbulence modeling approaches used in the Helios code. Helios is a dual-mesh overset unstructured/Cartesian RANS solver developed by the US Army for high-fidelity simulation of rotorcraft aeromechanics. The paper will present validations of standard 3D flowfields using the current near-body unstructured code NSU3D as well as the new strand mesh solver that is intended to be adopted over the next few years.
Topics: DTIC Archive, UTAH STATE UNIV LOGAN, *COMPUTATIONAL FLUID DYNAMICS, COMPUTERIZED SIMULATION, FLOW...
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This report contains experimental and analytical predictions of the seakeeping characteristics applicable to the DD 993 in accordance with a ship displacement of 8000 tons. Random wave experimental results are presented for various sea states at various ship speeds and headings. Roll motions are predicted for irregular, short-crested seas for various sea states at various ship speeds and headings. Roll is largest at the 70 degree heading; while the 100 degree heading results in the largest...
Topics: DTIC Archive, McCallum,Donald, NAVAL SHIP ENGINEERING CENTER WASHINGTON D C, *SHIP MOTION,...
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The Dynamic Flight Student Flow Model is a time-weighted capacitated network on which an optimizing algorithm operates to produce minimum time-to-train solutions. The model will provide an improved tool in the management and planning for an efficacious flow of students both with respect to internal efficiency of the Undergraduate Pilot Training Program and with regard to the external impact of different input and output policies. The numerical results and conclusions are given for two realistic...
Topics: DTIC Archive, Caves,William E, GEORGE WASHINGTON UNIV WASHINGTON D C PROGRAM IN LOGISTICS,...
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This report presents a model for performing reliability analyses of airfield lighting systems. A set of consecutive coefficients was developed to account for system failure criteria which include random light outages, consecutive light outages, and consecutive light bar failures. Probability theory and simulation techniques are used with the consecutive coefficients to determine system reliability. A computerized version of the model was used in a sensitivity analysis to determine the effect on...
Topics: DTIC Archive, Lindow,E S, CONSTRUCTION ENGINEERING RESEARCH LAB (ARMY) CHAMPAIGN ILL, *LIGHTING...
This document presents the oral version of a presentation given at the Military Application Section of the Joint National Meeting of the Operations Research Society of America and The Institute of Management Science, held in Milwaukee, Wisconsin, 15-17 October 1979.
Topics: DTIC Archive, Stallworth, Lewis A, NAVAL UNDERWATER SYSTEMS CENTER NEW LONDON CT, *COMPUTERIZED...
To determine the operational time required to mechanically control nuisance-level growth of aquatic plants in Buffalo Lake, Wisconsin, a computer model (HARVEST) was used which simulates all important steps in a mechanical control operation. Model inputs include plant density, distance to nearest disposal site, and mechanical and performance specifications for the harvesting system used. Plant densities were determined at two different times during the growing season by conducting a...
Topics: DTIC Archive, Sabol,B M, ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS ENVIRONMENTAL LAB,...
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This report concludes our study of large-scale vectorized numerical analysis applied to time domain seismic wave phenomena in filled basins. Applications include calculations of waves from simple surface or buried sources in a variety of idealized 2-D Basin and Range models (36,000 to 120,000 nodes) described in an interim report, and one large 3-D model (400,000 nodes) from Yucca Flat, Nevada Test Site, described here. Analysis is based on an explicit, finite element, elastic wave solver...
Topics: DTIC Archive, Wojcik,G L, WEIDLINGER ASSOCIATES MENLO PARK CA, *SEISMIC WAVES, *BASINS(GEOGRAPHIC),...
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This research note summarizes three years of a four year contract to study ways of improving human performance in highly integrated systems in such areas as communications, transportation, manufacturing, etc. Rule-based computer models of human performance (CAIN) are discussed, as are methods form measuring the complexity of the task of monitoring these large-scale systems. Finally, the development of a computer model (MABEL) which requires subjects to monitor a large-scale communications...
Topics: DTIC Archive, Rouse, William B, GEORGIA INST OF TECH ATLANTA CENTER FOR HUMAN-MACHINE SYSTEMS...
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Theory and examples are shown for a feasible method of estimating responses of equipment to an exercise torpedo against the hull of a submarine. The equipment is modeled as a linear and elastic system whose normal modes of vibration respond in accordance with their weight and frequency. A simple method is used for determining the effect weight of a normal model. The method is applicable to multiple models and independent motions of multiple supports. Keywords: Submarine hulls; Torpedo impact.
Topics: DTIC Archive, Bory, R L, NAVAL RESEARCH LAB WASHINGTON DC, *SUBMARINE HULLS, *DYNAMIC RESPONSE,...
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Lateral-load tests were performed on a large-scale, well-instrumented group of piles in sand. A similar single pile, also well-instrumented, was tested in the same soil. The group of piles and the single pile were installed in Houston for previous research projects. The native clay soil was removed from the upper portion of the piles and replaced with clean sand. Cyclic lateral loads were applied to the piles, and the response of the instrumentation was recorded. The results of the loads test...
Topics: DTIC Archive, Morrison, Clark S, TEXAS UNIV AT AUSTIN GEOTECHNICAL ENGINEERING CENTER, *PILE...
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The capability to transfer the positions of features from a given level of an integrated circuit layout to the focused ion beam machine is important in most of the intended applications of focused ion beams implantation. The capability is developed to transfer patterns written in MAGIC (a layout software system) to the focused ion beam format. The machine development was used to implant the channels on Si-NMOS devices. A test structure was used where each die had 256 transistors each one with...
Topics: DTIC Archive, Melngailis, John, MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS,...
The random access machine (RAM) and the Turing machine (TM) are the standard models for sequential computation. Research into the use to time and space by these and other models gives us insight into their computational power. This research includes analyzing how two different models use time and space, and comparing time and space utilization within a single model. Another avenue of investigation is determining how altering the definitions of time and space (for example, log-cost versus...
Topics: DTIC Archive, Loui, Michael C, ILLINOIS UNIV AT URBANA COORDINATED SCIENCE LAB, *ALGORITHMS,...
This dissertation develops new techniques for variance reduction in computer simulation. It demonstrates that applying nonlinear transformations to control variables can increase their effectiveness over linear controls. It shows how one can reduce the variance of quantile estimates, where the quantile of interest is a continuous and strictly monotone transformation of the control quantile, by transforming the control quantile with a different continuous and strictly monotone transformation....
Topics: DTIC Archive, Ressler, Richard L, NAVAL POSTGRADUATE SCHOOL MONTEREY CA, *COMPUTERIZED SIMULATION,...
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This research project produced a multi-job/force-level analysis model with supporting software. Incorporated in the Simulation Utility Management System (SUMS) are the abilities to: (a) consider the allocation of personnel within a dynamic multi-job system, (b) assess the interdependencies among utility estimates in the multi-job system, (c) investigate potential tradeoffs between single job and overall force-level utilities, and (d) perform sensitivity analyses of the effects of changes in...
Topics: DTIC Archive, Stone, Brice M, METRICA INC BRYAN TX, *COMPUTERIZED SIMULATION, *PERSONNEL...
The finite element model has become the standard way in which complex structural systems are modeled, analyzed, and the effects of loading simulated. A new method is developed for comparing the finite element simulation to experimental data, so the model can be validated, which is a critical step before a model can be used to simulate the system. An optimization process for finite element structural dynamic models utilizing sensitivity based updating is applied to the model updating and damage...
Topics: DTIC Archive, Renken, Jay A., NAVAL POSTGRADUATE SCHOOL MONTEREY CA, *MATHEMATICAL MODELS, *FINITE...
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The direct numerical simulations of the temperature field in water were used to investigate light scattering caused by turbulent temperature inhomogeneities and to compare it with scattering caused by typical seawater particulates in two extreme cases: coastal and open ocean conditions. The particle contribution was simulated using Mie theory aided by theoretical considerations to describe scattering at small angles. Distributions of particles observed in an open ocean and a coastal environment...
Topics: DTIC Archive, Domaradzki, J. A., UNIVERSITY OF SOUTHERN CALIFORNIA LOS ANGELES DEPT OF AEROSPACE...
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Grain-scale sorption mass transfer is an important process that must be considered when predicting clean-up time and choosing remediation techniques for subsurface hazardous waste contamination. Rate-limited sorption is responsible for the rebound effect, where remediated groundwater is recontaminated by desorption. Sorbed contaminants are not available for microbial degradation, and the desorption rate may govern the effectiveness of natural attenuation by biodegradation. Grain-scale sorption...
Topics: DTIC Archive, Mika, Karla K, AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH, *SOIL REMEDIATION,...
Within the scope of the project 'Feasibility study of an IM-ignitor' research has been carried out to develop a new ignitor to be used in a rocket system. In this project many aspects have been highlighted, especially on the area of Cook-off. The aspects of interest for Cook-off, the Thermal Initiation project, will be described in this report. With the computer models, partly developed during the feasibility-project, combined Thermal/chemical and thermal/chemical/pressure calculations have be...
Topics: DTIC Archive, Scholtes, J. H., PRINS MAURITS LABORATORIUM TNO RIJSWIJK(NETHERLANDS), *THERMAL...
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Overview and summaries of presentations at the Human Performance in Simulation Workshop, 30-31 July, 1997.
Topics: DTIC Archive, Johnson, Edgar, ARMY RESEARCH INST FOR THE BEHAVIORAL AND SOCIAL SCIENCES ALEXANDRIA...