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188

Jun 21, 2010
06/10

by
Allen, W. H.; Haines, R. F

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Irradiation phenomenon related to manual navigation

Topics: FEEDBACK CONTROL, SYSTEMS ENGINEERING, MATHEMATICAL MODELS, OPTIMAL CONTROL, SYSTEMS ANALYSIS,...

529
529

Jun 21, 2010
06/10

by
Balzer, D. L.; Barksdale, T. R.; Bowman, T. E.; Gilmore, D. E.; Gorman, D. N.; Hise, R. E., et al

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Detail design for advanced propellant management system for spacecraft propulsion systems

Topics: COLLAPSE, SIMPLIFICATION, CYLINDRICAL BODIES, DIFFERENTIAL EQUATIONS, SIMILARITY THEOREM,...

286
286

May 22, 2011
05/11

by
Benjamin, Theodore G.; Garcia, Roberto; Mcconnaughey, Paul K.; Wang, Ten-See; Vu, Bruce T.; Dakhoul, Yousse

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These analyses were undertaken to aid in the understanding of flow phenomena in the Alternate Turbopump Development (ATD) High-pressure Oxidizer Turbopump (HPOTP) Pump-end ball bearing (PEBB) cavities and their roles in turbopump vibration initiation and bearing distress. This effort was being performed to provide timely support to the program in a decision as to whether or not the program should be continued. In the first case, it was determined that a change in bearing through flow had no...

Topics: ANNIHILATION REACTIONS, QUANTUM OPTICS, VECTORS (MATHEMATICS), WAVE FUNCTIONS, COHERENCE,...

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383

Jun 15, 2011
06/11

by
Bowen, R. L.; Sundeen, D. A

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Major, dominantly compressional, orogenic episodes (Taconic, Acadian, Alleghenian) affected eastern North America during the Paleozoic. During the Mesozoic, in contrast, this same region was principally affected by epeirogenic and extensional tectonism; one episode of comparatively more intense tectonic activity involving extensive faulting, uplift, sedimentation, intrusion and effusion produced the Newark Series of eposits and fault block phenomena. This event, termed the Palisades...

Topics: COMPUTERIZED SIMULATION, PREDICTIONS, TIME SERIES ANALYSIS, VISCOELASTICITY, CONSTITUTIVE...

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241

Jun 15, 2011
06/11

by
Casasent, D

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Advanced problems in computational fluid dynamics, finite element structural analysis, and related areas require the solution of large partial differential equations and matrices of large size and dynamic range. This project considers an advanced parallel linear algebra processor and associated novel parallel algorithms for such applications. Research on system fabrication, quantitative performance evaluation and new parallel algorithms are described and considered. Case studies in structural...

Topics: FUEL CONSUMPTION, OPTIMAL CONTROL, POSITIONING, SPIN STABILIZATION, ALGORITHMS, BOUNDARY VALUE...

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406

Jun 9, 2011
06/11

by
Dean, Edwin B.; Wood, Darrell A.; Moore, Arlene A.; Bogart, Edward H

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In most cost estimating applications at the NASA Langley Research Center (LaRC), it is desirable to present predicted cost as a range of possible costs rather than a single predicted cost. A cost risk analysis generates a range of cost for a project and assigns a probability level to each cost value in the range. Constructing a cost risk curve requires a good estimate of the expected cost of a project. It must also include a good estimate of expected variance of the cost. Many cost risk...

Topics: AIRFOILS, DISCRETIZATION (MATHEMATICS), MACH NUMBER, PERTURBATION, SHAPE FUNCTIONS, AERODYNAMIC...

Using brightness temperature Tb measurements from L-band airborne microwave radiometers, with independent sea surface temperature (SST) observations, sea surface salinity (SSS) can be remotely determined with errors of about 1 psu in temperate regions. Nonlinearities in the relationship between $Tb$, SSS, and SST produce variations in the sensitivity of salinity S to variations in Tb and SST. Despite significant efforts devoted to SSS remote sensing retrieval algorithms, little consideration...

Topics: DTIC Archive, NAVAL RESEARCH LAB STENNIS SPACE CENTER MS OCEANOGRAPHY DIV, *COASTAL REGIONS,...

This study is devoted primarily to solid-solid impact at velocities in the meteoric range. A continuous Eulerian hydrodynamic code is used to numerically integrate the flow equations for several series of impact problems. The impact velocity, the projectile shape, the density of the projectile, and the equation of state of the interacting materials are varied. Impact crater dimensions are found to increase as the 0.58 power of the impact velocity. Projectiles of the same mass but different...

Topics: DTIC Archive, Walsh, J M, GENERAL DYNAMICS SAN DIEGO CA GENERAL ATOMIC DIV, *BALLISTICS,...

A computer model is presented for the calculation of the thermodynamic properties of air and the exhaust gas from a gas turbine. The model was developed specifically to include the requirements for on-line data reduction systems. These requirements include minimum memory and calculation time and constituents and their thermodynamic properties that may be readily located and altered if necessary. The model is based on air and hydrocarbon fuels and includes real gas effects (intermolecular forces...

Topics: DTIC Archive, Pelton, John M, ARNOLD ENGINEERING DEVELOPMENT CENTER ARNOLD AFB TN, *COMPUTERIZED...

The compressible hydrodynamic approach previously developed for small Mach number non-cavitating flows has been extended to simulate cavitating flows as well as non-cavitating flows. The extension is made possible by assuming a complex equation of state relating density and pressure to cover the liquid phase and the gas phase. Thus, the cavitation phenomenon is regarded as a single-phase flow phenomenon enabling the elimination of the cavity closure condition. The numerical model is an unsteady...

Topics: DTIC Archive, Song, Charles C., MINNESOTA UNIV MINNEAPOLIS ST ANTHONY FALLS HYDRAULIC LAB,...

This report results from a contract tasking University of Cassino as follows: The contractor shall investigate the behavior of ductile metals under high strain rates at various temperatures. The contractor shall produce a new advanced model for predicting ductile failure in metals using continuum mechanics and solid state equations.

Topics: DTIC Archive, Bonora, Nicola, CASSINO UNIV (ITALY), *CONTINUUM MECHANICS, METALS, ALLOYS, STRAIN...

The experimentally observed behavior of systems of high explosives, low density (0.5- and 0.3-g/cc) polyurethane foam, and metals can be numerically reproduced if the foam is assumed to decompose and the decomposition products are described by a BKW equation of state.

Topics: DTIC Archive, Mader, Charles L., LOS ALAMOS SCIENTIFIC LAB ALBUQUERQUE NM, *POLYURETHANE RESINS,...

These lectures review some basic results of detonation theory and are specialized to serve as an introduction to the theory of Detonation Shock Dynamics (DSD). The theory of DSD is a time dependent, multidimensional theory for the propagation of near Ohapman Jouguet (OJ) detonations. This theory is especially relevant to applications of detonation propagation in condensed explosives and the basic dynamics in freely propagating gaseous explosives as well. The theory that we present is based on...

Topics: DTIC Archive, Stewart, D. S., ILLINOIS UNIV AT URBANA DEPT OF THEORETICAL AND APPLIED MECHANICS,...

An unsteady, hydrodynamic model of the impact of a low strength projectile on a rigid or semi-rigid target has been developed. Impact tests of various materials including birds, gelatin, and RTV rubber have been conducted to validate this theory. At velocities above 100 m/s, these materials were seen to flow as a fluid upon impact. The resulting impact pressure histories were very similar to those predicted using the model. The impact process was dominated by an initial shock phase which was...

Topics: DTIC Archive, Wilbeck, James S., AIR FORCE MATERIALS LAB WRIGHT-PATTERSON AFB OH, *IMPACT,...

A free piston compression tube has been used to generate samples of nitrogen and air test gases pressures up to 3000 kg/sq cm and 2300K. A description of the measurement of pressure, temperature and volume (driving part of the cycle) has been made. Calculations and experiments have been carried out which have indicated the level of uncertainty of measurement of these parameters. The results of the experiments in nitrogen have shown that agreement with the equation of state at low conditions is...

Topics: DTIC Archive, Rouel, Georges P, Richards, Bryan E, VON KARMAN INST FOR FLUID DYNAMICS...

Partial Contents: Numerical Simulations of the Vlasov-Maxwell Equations by Coupled Particle-Finite Element Methods on Unstructured Meshes; Electromagnetic PIC Simulations Using Finite Elements on Unstructured Grids; Modelling Travelling Wave Output Structures with the Particle-in-Cell Code CONDOR; SST--A Single-Slice Particle Simulation Code; Graphical Display and Animation of Data Produced by Electromagnetic, Particle-in-Cell Codes; A Post- Processor for the PEST Code; Gray Scale Rendering of...

Topics: DTIC Archive, NAVAL RESEARCH LAB WASHINGTON DC, *SYMPOSIA, *PLASMAS(PHYSICS), *DIGITAL SIMULATION,...

The hydrodynamic theory of Part I should permit the calculation of the detonation velocity of an explosive if the following information were available: composition, heat of formation, density, and equation of state of the products. Unfortunately no completely satisfactory a priori equation of state data are available for these high temperatures and pressures. However, an approximate form of the equation of state (Becker) Is available containing one unknown constant (which is a function of the...

Topics: DTIC Archive, Kistiakowsky, G B, OFFICE OF SCIENTIFIC RESEARCH AND DEVELOPMENT WASHINGTON DC...

A classical result of Gilbarg states that a simple shock wave solution of Euler's equations in compressive if and only if a corresponding shock layer solution of the Navier-Stokes equations exists, assuming, among other things, that the equation of state is convex. An entropy condition appropriate for weeding out unphysical shocks in the nonconvex case has been introduced by Liu. For shocks satisfying his entropy condition, Liu showed that purely viscous shock layers exist (with zero heat...

Topics: DTIC Archive, Pego,Robert L, WISCONSIN UNIV-MADISON MATHEMATICS RESEARCH CENTER, *SHOCK WAVES, *GAS...

The BLAF programs (BLAFS, BLAFOP, and BLAFHI) are designed to reconstruct parts of a spherical blast field from selected pressure history observations. The reconstruction method is based on a model fitting to the observed flow field and a subsequent numerical integration of the flow governing equations. This manual gives a short outline of the theoretical background, a description of the program and specifications for the input data and their formats. The flow field reconstruction is done in...

Topics: DTIC Archive, Celmins, Aivars, ARMY BALLISTIC RESEARCH LAB ABERDEEN PROVING GROUND MD,...

The response of the seasonal thermocline formation and mixing to prescribed vertical interior motion is examined. For the annual and shorter period interior motion cases studied, the response was strongest for the annual period. For an oscillatory vertical motion having a 15 m amplitude at a 75 m depth, warm sea surface temperature anomalies of up to 2.16 C and cold anomalies of up to 2.04 C are found, depending on the phase difference between the interior motion and the annual heat cycle. The...

Topics: DTIC Archive, Garner,J P, NAVAL POSTGRADUATE SCHOOL MONTEREY CA, *Thermoclines, *Mixed...

This work centers on the recasting of the Rachford-Rice objective function into a polynomial function of the vapor fraction. The degree of this polynomial is one less than the number of components in the system and its coefficients can be calculated from the feed composition and the equilibrium ratios. A recursive expression is developed that involves symmetric functions and can be easily programmed on a computer, or scientific calculator. The principal advantage of this new form of the...

Topics: DTIC Archive, Weigle, Brett D, PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MINERAL ENGINEERING,...

Topics: DTIC Archive, RINEY, T D, GENERAL ELECTRIC CO PHILADELPHIA PA MISSILE AND SPACE DIV, *HYPERVELOCITY...

This report documents research performed to enable the EPIC 3D lagrangian hydrocode to run in a linked mode with the hull 3D Eulerian hydrocode. The linked mode is required to efficiently and accurately model multiple target plate impact and penetration events. The report also documents many changes made to make EPIC more user oriented and simple to run.

Topics: DTIC Archive, Osborn, John J, ORLANDO TECHNOLOGY INC SHALIMAR FL, *ARMOR PIERCING AMMUNITION,...

The Fermi-Thomas method is used in this paper to calculate the cohesive energy of metals. The preliminary results obtained indicate that there is a minimum value involved in the relation between the energy and the crystal lattice constant of a metal. For heavy metal, the atomic spacing corresponding to this minimum value are shown to be close to the experimental values; however, for univalent alkali metals, the theoretical values are too small, and the cohesive energies so obtained are much...

Topics: DTIC Archive, JOINT PUBLICATIONS RESEARCH SERVICE ARLINGTON VA, *METALS, *FERMI SURFACES,...

Contents: Introduction-Reasons for Studying Spherical Shock Waves, Physics of Cavity Expansion due to Explosive Impact, General Nature of Shock Waves, and Statement of Problem and Scope of Thesis; Brief Review of Past Work-Elastic Plastic Effects, Similarity Solutions of Equations of Gas Dynamics, Self-Similar Solutions of the Problem of Cratering Due to Hypervelocity Impact, and Numerical Integration of the Differential Equation of Spherical Blast Waves in a Gas and Hydrodynamics of...

Topics: DTIC Archive, Calvit, Harry H, PENNSYLVANIA STATE UNIV STATE COLLEGE, *SHOCK WAVES, ALUMINUM,...

The Mie-Gruneisen equation of state (EOS) is further examined for restrictions upon the form of the Gruneisen parameter. Employing basic thermodynamic rules and applying them to the Mie-Gruneisen EOS, a more restrictive condition is offered for the Gruneisen parameter, which extends previous work on the subject. Stability, Hugoniot, Cold curve, Shock, Equation of state, Mie-Gruneisen, Hydrocode.

Topics: DTIC Archive, Segletes, Steven B, ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD, *THERMODYNAMICS,...

Elementary basic solutions of the equations of motion of a compressible fluid in the hodograph variables are developed and used to provide a basis for comparison, in the form of velocity correction formulas, of corresponding compressible and incompressible flows. The known approximate results qt Chaplygin, von Kdrman and Tsien, Temple and Yarwood, and Prandtl and Glauert are unified by means of the analysis of the present paper. Two new types of approximations, obtained from the basic...

Topics: DTIC Archive, Garrick, I. E., NATIONAL AERONAUTICS AND SPACE ADMINISTRATION WASHINGTON DC,...

In this paper the authors study scaling rules and round-off noise variances in a fixed point implementation of the Kalman predictor for an ARMA time series observed noise-free. The Kalman predictor is realized in a fast form that uses the so-called fast Kalman gain algorithm. The algorithm for the gain is fixed point. Scaling rules and expressions for rounding error variances are derived. The numerical results show that the fixed point realization performs very closely to the floating point...

Topics: DTIC Archive, Scharf,L L, RHODE ISLAND UNIV KINGSTON DEPT OF ELECTRICAL ENGINEERING, *MATHEMATICAL...

A comprehensive discussion is given of various simple models of explosively driven metal. These are compared with each other and with experiments, wherever possible, and their relation to more complicated models is discussed as needed. Certain types enable us to describe detailed space-time trajectories, while others are more suitable for asymptotic cases, such as estimating launch velocities. All are simple enough to use in initial design work where insight and suggestions for experiment are...

Topics: DTIC Archive, Dehn, James T, ARMY BALLISTIC RESEARCH LAB ABERDEEN PROVING GROUND MD, *DETONATIONS,...

Detonation wave profiles are obtained using a realistic dense fluid equation of state. These profiles are compared to the predictions of the simplified Zeldovich Von Neumann Doering model. Methods are developed for simulating the rapid uniaxial compression of solids suited to molecular dynamics simulation. the interatomic distribution function are formulated in solids, for comparison with atomistic simulations and use in kinetic reaction models. The next two years will concentrate on reaction...

Topics: DTIC Archive, Hoover, William G, CALIFORNIA UNIV LIVERMORE DEPT OF APPLIED SCIENCE, *DETONATION...

This project demonstrates the usefulness of front tracking as a tool to study the fully compressible axially symmetric expansion and collapse of an underwater explosion bubble in two spatial dimensions. In the pilot project supported by this contract, a one-dimensional version of the front tracking code is being implemented to compute spherically symmetric oscillations. The one dimensional version will be used to gain expertise in the problem, to pinpoint areas of difficulty, and to determine...

Topics: DTIC Archive, Lindquist, W B, NEW YORK UNIV NY COURANT INST OF MATHEMATICAL SCIENCES, *UNDERWATER...

Results are presented for a range of one-dimensional shock wave problems in gaseous and metallic materials. These problems were solved numerically using Flux-Corrected Transport (FCT). FCT is a numerical technique which achieves high resolution without non-physical oscillations, especially in regions of steep gradients such as shock fronts. These types of problem involve solving the Eulerian inviscid fluid flow equations, namely the continuity equation, conservation of momentum and conservation...

Topics: DTIC Archive, Tyndall, Moya B, MATERIALS RESEARCH LABS ASCOT VALE (AUSTRALIA), *SHOCK(MECHANICS),...

Calculations are made of the intrathoracic pressure expected from blast loading of sheep. A mathematical model of the chest wall and lung parenchyma have been formulated as a system of differential equations which include the effects of chest wall mass and resistance, density of the parenchyma and an adiabatic equation of state for air within the parenchyma. The differential equations are discretized as a system of nonlinear finite difference equations with the blast loading appearing as a...

Topics: DTIC Archive, Vander Vorst, Michael J, JAYCOR SAN DIEGO CA, *MECHANICAL PROPERTIES, *OVERPRESSURE,...

This report is concerned with a proper treatment of disturbances in the ionosphere. It develop the treatment of the excitation of extra-low frequency (magnetohydrodynamic-like) wave-motions in an infinite, homogeneous plasma imbedded in a constant, unidirectional magnetic field, for which the electrical conductivity tensor is easily established and methods of analysis are highly developed.

Topics: DTIC Archive, Cantor, A, SYLVANIA ELECTRIC PRODUCTS INC WALTHAM MA, *IONOSPHERIC PROPAGATION,...

A 1-D radiation hydrodynamics code is employed to model the interaction of the NIKE KrF laser with a planar CH target. Three cases are compared to demonstrate the effects of radiative preheat: (1) the hydrodynamics of the laser target interaction with a high density equation-of-state (EOS) but without radiation; (2) the inclusion of radiation production and transport using collisional radiative equilibrium for the ionization dynamics; and (3) the addition of an approximate model for the...

Topics: DTIC Archive, Giuliani, John L , Jr, NAVAL RESEARCH LAB WASHINGTON DC, *RADIATION,...

A review of fundamental shock-transition theory is presented. The equation of state (EOS) is introduced as an analytical vehicle to express material pressure as a function of density and temperature (or internal energy in the case of adiabatic transition). Starting from the fundamental laws of thermodynamics, three criteria are developed to measure the stability of equations of state and are applied specifically to the Mie-Gruneisen EOS, with Hugoniot reference, to investigate the stability...

Topics: DTIC Archive, Segletes, Steven B, ARMY BALLISTIC RESEARCH LAB ABERDEEN PROVING GROUND MD,...

The purpose of this effort is to create an analytical physics based aircraft-MANPADS model capability that includes impact, detonation, penetration, and wing flutter response. This work extends an existing body-on-body missile model to include energetic materials, fragmentation effects and wing flutter response due to dynamic air loads. The detonation of the high explosive within the missile, as well as the expansion of the surrounding fluids, was modeled in the Eulerian domain. The...

Topics: DTIC Archive, Hinrichsen, Ronald L, RHAMM TECHNOLOGIES LLC BELLBROOK OH, *AIR DEFENSE, *SIMULATION,...

Topics: DTIC Archive, Goldstein, Arthur W, NATIONAL AERONAUTICS AND SPACE ADMINISTRATION CLEVELAND OH LEWIS...

Attention is focussed on the asymptotic stress and deformation fields near the edge of a mode I crack propagating steadily in an elastic perfectly plastic incompressible material under plane strain conditions. Features of previously reported results on this problem are reviewed, with a view toward establishing discriminating characteristics. An asymptotic solution valid for all crack speeds is constructed. This solution has the properties that the angular variation of stress and particle...

Topics: DTIC Archive, Leighton, J T, BROWN UNIV PROVIDENCE RI DIV OF ENGINEERING, *CRACK PROPAGATION,...

Derivation of the two-phase (reactive particle) unsteady-flow conservation equations are presented based upon the generally accepted concept of separated-flow. The resulting formulation is compared with those equations derived by others, and questions are raised as the correctness or interpretation made by previous modelers. Details of the numerical method chosen to solve these equations (an explicit two-step MacCormack scheme) are also presented. Solutions are presented that predict the...

Topics: DTIC Archive, Krier,Herman, ILLINOIS UNIV AT URBANA-CHAMPAIGN DEPT OF AERONAUTICAL AND...

In this paper we are concerned with the existence of optimal controls for problems of the following kind. The state and observation processes are governed by stochastic differential equations. Instead of allowing only strict-sense controls, we obtain existence of a minimum in a wider class of controls. Our results together with a counterexample of Varadhan strongly suggest that, if there is indeed a general existence theorem for strict sense optimal controls, then standard methods are not...

Topics: DTIC Archive, Fleming,Wendell H, BROWN UNIV PROVIDENCE RI LEFSCHETZ CENTER FOR DYNAMICAL SYSTEMS,...

We report on the investigation of the equation of state of an 2Al+Fe2O3+ 50 wt.% epoxy composite in the 2-23 GPa pressure range. An explosive loading technique, with piezoelectric pins to measure the shock velocity in the sample and in a donor material, was used for experiments exceeding 5 GPa. Gas gun experiments were performed on the same composites at lower pressures, using PVDF stress gauges to record the input and propagated stresses and the shock velocity based on the time of travel...

Topics: DTIC Archive, Jordan, Jennifer L, AIR FORCE RESEARCH LAB EGLIN AFB FL MUNITIONS DIRECTORATE,...

A theory is presented to describe the coupled thermal and mechanical behavior of solids which exhibit irreversibility. The developments presented are restricted to definitions and analyses of 'equilibrium states.' The foundations of the theory embody the following assumptions: (1) the local equilbrium state is fully characterized by three state variables - i.e. the deformation gradient, the entropy density, and a substate variable, (2) a caloric equation of state and stress and temperature...

Topics: DTIC Archive, McDonough,Thomas B, AERONAUTICAL RESEARCH ASSOCIATES OF PRINCETON INC NJ, *PLASTIC...

Topics: DTIC Archive, Farmer, Richard, Cheng, Gary, Chen, Yen-Sen, SECA INC HUNTSVILLE AL, *COMPUTATIONAL...

A novel method is described from which estimates of the internal pressure or temperature of highly accelerated material can be made. The technique is applied to Nd-laser ablatively accelerated targets and the results compare well with target rear surface temperature measurements using time-resolved optical pyrometry. (Author)

Topics: DTIC Archive, Ripin,B H, NAVAL RESEARCH LAB WASHINGTON DC, *LASER INDUCED FUSION, *ENERGY TRANSFER,...

As a contribution to the investigation of the suitability of using cryogenic nitrogen as the test gas in a high Reynolds number transonic wind-tunnel, a study is made here of the real gas effects of nitrogen at low temperatures. The study, which is limited to inviscid, homentropic flow of an non-conducting gas, takes the form of an independent confirmation of results by Kilgore et al. A recent paper by Wagner and Schmidt on this subject employs a different equation of state from that used here...

Topics: DTIC Archive, Albone,C M, ROYAL AIRCRAFT ESTABLISHMENT FARNBOROUGH (ENGLAND), *NITROGEN, *TRANSONIC...

Clarifications and observations are made regarding Segletes' equation of state, in response to recent comments and criticisms. A theoretical justification for the form of the equation of state is laid out in more precise detail. The model is shown to produce high-quality fits to shock, as well as cold-compression data, especially when accounting for the experimental variability of the model input parameters. The falseness of the correspondence between the volumetric and vibrational spring...

Topics: DTIC Archive, Segletes, Steven B., ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD, *ALUMINUM,...

The goal of the report is description of work of the equation-of-state (EOS) code. It requires minimum knowledges in hydrodynamics, thermodynamics, and programming. The manual is devoted to typical hypercode user with an expenence in numerical modeling of such processes, as high velocity impact, for example.

Topics: DTIC Archive, Lomonosov, I. V., RUSSIAN ACADEMY OF SCIENCES MOSCOW HIGH ENERGY DENSITY RESEARCH...

In Bayesian estimation, the objective is to calculate the complete density function for an unknown quantity conditioned on noisy observations of that quantity. This work considers recursive estimation of a nonlinear discrete-time system state using successive observations. The formal recursion for the density function is easily written, but generally there is no closed form solution. The numerical solution proposed here is obtained by modifying the recursion and using a simple piece-wise...

Topics: DTIC Archive, Kramer,S C, AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH, *ESTIMATES, *RECURSIVE...

This document is the sixth semiannual report and the final report of a basic study of the modes of injection lasers. The concern is the fundamental relationship between the modal properties of diode lasers, their structure, and the nature of the electrical drive. The semiannual report features three pioneering studies: The development of an equation of state relating the laser power, spectrum, and beam profile to the input current and laser structure; the behavior of the laser on transition of...

Topics: DTIC Archive, Sommers,H S , Jr, RCA LABS PRINCETON NJ, *INJECTION LASERS, THRESHOLD EFFECTS,...