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267
Jun 9, 2011
06/11
by
Abdel-Magid, Beckr
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Winona State University is an undergraduate institution, and the composite materials engineering program is an ABET accredited undergraduate program offering B.S. degree in Composite Materials Engineering (CME). Over the last three years, eight students in the CME program have worked in this research project. These students gained hands-on research experience in planning a research project, brainstorming, literature review, experimentation, data analysis, discussion of results, documentation of...
Topics: ATMOSPHERIC DENSITY, INTERNATIONAL SPACE STATION, IONOSPHERIC TEMPERATURE, LOW EARTH ORBITS,...
220
220
Jun 9, 2011
06/11
by
Abdel-Magid, Beckr
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eye 220
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A major issue for many designers and engineers is the long-term mechanical properties of polymer matrix composites (PMC). These composites are being used more than ever in high-performance applications; and engineers need to understand the characteristics of polymeric behavior as they relate to the time-dependent mechanical properties, or viscoelastic properties. The viscoelastic nature of polymers dominates the mechanical properties of polymeric composites. Failure modes such as excessive...
Topics: LOW EARTH ORBITS, HELIUM, FIELD OF VIEW, ELECTRON IMPACT, SOLAR WIND, SPACECRAFT CHARGING,...
208
208
Jul 25, 2010
07/10
by
Addy, Harold E., Jr.; Keith, Theo G., Jr
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The flow in the diffuser section of the Icing Research Wind Tunnel at NASA Lewis Research Center is investigated using both tunnel calibration measurements and numerical simulation techniques. Local pressure and temperature measurements are made to establish velocity and temperature profiles in the diffuser of the tunnel. These profiles are compared with similar measurements made prior to renovating the equipment which generates the tunnel's icing cloud. This comparison indicates the manner in...
Topics: ENERGY REQUIREMENTS, SOLAR ENERGY CONVERSION, SPACE POWER REACTORS, SPACE TRANSPORTATION,...
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976
Jul 26, 2010
07/10
by
Arbit, H. A.; Tuegel, L. M.; Dodd, F. E
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The Heavy Hydrocarbon Main Injector Program was an analytical, design, and test program to demonstrate an injection concept applicable to an Isolated Combustion Compartment of a full-scale, high pressure, LOX/RP-1 engine. Several injector patterns were tested in a 3.4-in. combustor. Based on these results, features of the most promising injector design were incorporated into a 5.7-in. injector which was then hot-fire tested. In turn, a preliminary design of a 5-compartment 2D combustor was...
Topics: ATOMIC BEAMS, MASS SPECTROMETERS, NEUTRAL ATOMS, QUADRUPOLES, REAL TIME OPERATION, EARTH ORBITAL...
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400
Jun 9, 2011
06/11
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Bement, Laurence J
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Since no generally accepted guidelines exist on sizing booster charges to assure functional margins in pyrotechnically actuated devices, a study was conducted to provide an approach to meet this need. An existing pyrovalve was modified from a single cartridge input to a dual-cartridge input with a booster charge. The objectives of this effort were to demonstrate an energy-based functional margin approach for sizing booster charges, and to determine booster charge energy delivery characteristics...
Topics: DURABILITY, LOW EARTH ORBITS, OXYGEN ATOMS, DIATOMIC MOLECULES, EARTH ORBITAL ENVIRONMENTS, GAS...
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271
Jul 12, 2010
07/10
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Bergeron, R. P.; Weldon, V. A
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The development of a reusable and space-based orbital transfer vehicle (OTV) necessitates an integral approach toward structural and propulsion subsystems design. A single engine installation necessitates moving the engine further aft and/or relocation of the engine gimbal point to accommodate vehicle control requirements. Penalties associated with gimbal point relocation without increasing stage length or modifying typical advanced engine concepts, as well as a method for minimizing such...
Topics: AEROASSIST, THERMAL PROTECTION, AERODYNAMIC CHARACTERISTICS, LIFT DRAG RATIO, ORBIT TRANSFER...
258
258
May 27, 2011
05/11
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Bergstrom, R. W.; Kinne, S.; Sokolik, I. N.; Toon, O. B.; Mlawer, E. J.; Clough, S. A.; Ackerman, T. P.; Mather, J
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A new radiative transfer model combining the efforts of three groups of researchers is discussed. The model accurately computes radiative transfer in a inhomogeneous absorbing, scattering and emitting atmospheres. As an illustration of the model, results are shown for the effects of dust on the thermal radiation.
Topics: ORBIT CALCULATION, STANDARD DEVIATION, POSITION ERRORS, COVARIANCE, DOWNRANGE, CIRCULAR ORBITS,...
608
608
May 27, 2011
05/11
by
Bhatt, R. T.; Palczer, A. R
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Commercially available silicon powders were wet-attrition-milled from 2 to 48 hr to achieve surface areas (SA's) ranging from 1.3 to 70 sq m/g. The surface area effects on the nitridation kinetics of silicon powder compacts were determined at 1250 or 1350 C for 4 hr. In addition, the influence of nitridation environment, and preoxidation on nitridation kinetics of a silicon powder of high surface area (approximately equals 63 sq m/g) was investigated. As the surface area increased, so did the...
Topics: ACCELERATED LIFE TESTS, EARTH OBSERVING SYSTEM (EOS), SPACECRAFT POWER SUPPLIES, ELECTROLYTIC...
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Jun 9, 2011
06/11
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Bhatt, Ramakrishna T.; Pereira, J. Michael; Gyekenyesi, John P.; Choi, Sung R
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Foreign object damage (FOD) behavior of a gas-turbine grade SiC/SiC ceramic matrix composite (CMC) was determined at 25 and 1316 C, employing impact velocities from 115 to 440 meters per second by 1.59-mm diameter stell-ball projectiles. Two different types of specimen support were used at each temperature: fully supported and partially supported. For a given temperature, the degree of post-impact strength degradation increased with increasing impact velocity, and was greater in a partially...
Topics: SPACECRAFT CHARGING, COMPUTERIZED SIMULATION, SPACE ENVIRONMENT SIMULATION, GRAPHICAL USER...
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243
May 21, 2011
05/11
by
Blaisdell, G. A.; Zeman, O
texts
eye 243
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The dilatational dissipation rate within compressible homogeneous turbulent shear flow is studied using data from direct numerical simulations. It is found that the dilatational dissipation rate is mainly associated with large scale acoustic waves. Eddy shocklets are observed; however, they have little contribution to the average dissipation rate. A mechanism for the generation of eddy shocklets is shown to be the focusing of acoustic waves. Turbulence models for the dilatational dissipation...
Topics: MANNED MARS MISSIONS, NUCLEAR ELECTRIC PROPULSION, NUCLEAR FUELS, REACTOR DESIGN, MIRROR FUSION,...
397
397
May 31, 2011
05/11
by
Blandino, Joseph R.; Johnston, John D.; Dharamsi, Urmil K
texts
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Thin-film membrane structures are under consideration for use in many future gossamer spacecraft systems. Examples include sunshields for large aperture telescopes, solar sails, and membrane optics. The development of capabilities for testing and analyzing pre-tensioned, thin film membrane structures is an important and challenging aspect of gossamer spacecraft technology development. This paper presents results from experimental and computational studies performed to characterize the wrinkling...
Topics: TEMPERATURE MEASUREMENT, LOW EARTH ORBITS, ENVIRONMENT EFFECTS, AEROSPACE ENVIRONMENTS, AUTONOMY,...
175
175
May 28, 2011
05/11
by
Bookout, Paul S.; Ricks, E
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Through the development of a space shuttle payload, there are usually several coupled loads analyses (CLA) performed: preliminary design, critical design, final design and verification loads analysis (VLA). A final design CLA is the last analysis conducted prior to model delivery to the shuttle program for the VLA. The finite element models used in the final design CLA and the VLA are test verified dynamic math models. Mission 6A is the first of many flights of the Multi-Purpose Logistics...
Topics: EVALUATION, DIFFUSE RADIATION, EMITTANCE, INFRARED RADIATION, INTERNATIONAL SPACE STATION,...
500
500
Jul 11, 2010
07/10
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Bowyer, C. S.; Margon, B.; Lampton, M.; Paresce, F.; Stern, R
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Nonsolar sources in the extreme ultraviolet (EUV) region of the electromagnetic spectrum (10 to 100 nm) were observed by a grazing incidence telescope flown in the Apollo service module during the Apollo Soyuz Test Project. Ten nighttime orbits were used to obtain data on 30 preselected stars, 1 planet, and the EUV background radiation. Extrasolar EUV sources detected include: the hot white dwarfs HZ 43 and Feige 24, the dwarf nova SS Cygni, and the M-dwarf flare star Proxima Centauri.
Topics: ADAPTIVE CONTROL, LOW EARTH ORBITS, SATELLITE TRACKING, SPACECRAFT POWER SUPPLIES, LASERS, OPTICAL...
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207
Jun 12, 2011
06/11
by
Bozzolo, Guillermo; Noebe, Ronald D.; Mosca, Hugo O
texts
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Atomistic modeling of the site substitution behavior of Pd in NiTi (J. Alloys and Comp. (2004), in press) has been extended to examine the behavior of several other alloying additions, namely, Fe, Pt, Au, Al, Cu, Zr and Hf in this important shape memory alloy. It was found that all elements, to a varying degree, displayed absolute preference for available sites in the deficient sublattice. How- ever, the energetics of the different substitutional schemes, coupled with large scale simulations...
Topics: ATMOSPHERIC CORRECTION, AIRBORNE EQUIPMENT, REMOTE SENSING, RADIATIVE TRANSFER, IMAGING...
260
260
Jun 2, 2011
06/11
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Bronstein, Lyudmila M.; Karlinsey, Robert L.; Ritter, Kyle; Joo, Chan Gyu; Stein, Barry; Zwanziger, Josef W
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This paper reports synthesis, structure, and properties of novel hybrid solid polymer electrolytes (SPE's) consisting of organically modified aluminosilica (OM-ALSi), formed within a poly(ethylene oxide)-in-salt (Li triflate) phase. To alter the structure and properties we fused functionalized silanes containing poly(ethylene oxide) (PEO) tails or CN groups.
Topics: LIFE CYCLE COSTS, OPERATING COSTS, MANNED SPACE FLIGHT, LOW EARTH ORBITS, RELIABILITY ANALYSIS,...
182
182
Aug 1, 2010
08/10
by
Bryan, Kurt; Vogelius, Michae
texts
eye 182
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The problem of locating and identifying a collection of finitely many cracks inside a planar domain from measurements of the electrostatic boundary potentials induced by specified current fluxes is considered. It is shown that a collection of n or fewer cracks can be uniquely identified by measuring the boundary potentials induced by n 1 specified current fluxes, consisting entirely of electrode pairs.
Topics: DESIGN ANALYSIS, LOW EARTH ORBITS, MISSION PLANNING, ORBITAL SERVICING, RESCUE OPERATIONS, SPACE...
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245
Jul 21, 2010
07/10
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Chamis, C. C.; Hopkins, D. A
texts
eye 245
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A set of thermoviscoplastic nonlinear constitutive relationships (1VP-NCR) is presented. The set was developed for application to high temperature metal matrix composites (HT-MMC) and is applicable to thermal and mechanical properties. Formulation of the TVP-NCR is based at the micromechanics level. The TVP-NCR are of simple form and readily integrated into nonlinear composite structural analysis. It is shown that the set of TVP-NCR is computationally effective. The set directly predicts...
Topics: EARTH ORBITAL ENVIRONMENTS, EXPERIMENTATION, INTERPLANETARY DUST, LOW EARTH ORBITS, OPTICAL...
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276
May 31, 2011
05/11
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Chen, Shin-Juh; Dahm, Werner J. A.; Silver, Joel A.; Piltch, Nancy D
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The technique of Diode Laser Spectroscopy (DLS) with wavelength modulation is utilized to measure the concentration of methane in reacting vortex rings under microgravity conditions. From the measured concentration of methane, other major species such as water, carbon dioxide, nitrogen, and oxygen can be easily computed under the assumption of equilibrium chemistry with an iterative method called ITAC (Iterative Temperature with Assumed Chemistry). The conserved scalar approach in modelling the...
Topics: BOUNDARIES, RELIABILITY, STABILITY, DEEP SPACE, EXTRAVEHICULAR ACTIVITY, OBSERVATORIES, LIBRATION,...
2,834
2.8K
Jun 13, 2011
06/11
by
Chertok, Boris E
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As with Volume I, Boris Chertok has extensively revised and expanded the material in Volume II from the original Russian text. In this volume, Chertok takes up his life story after his return from Germany to the Soviet Union in 1946. At the time, Stalin had ordered the foundation of the postwar missile program at an old artillery factory northeast of Moscow. Chertok gives an unprecedented view into the early days of the Soviet missile program. During this time, the new rocket institute known as...
Topics: GLOBAL POSITIONING SYSTEM, EARTH LIMB, RADIO NAVIGATION, SPACE NAVIGATION, ALTITUDE, VELOCITY...
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193
Jul 23, 2010
07/10
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Claspy, P. C.; Bhasin, K. B
texts
eye 193
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Interdigitated photodetectors of various geometries have been fabricated on GaAlAs/GaAs heterostructure material. Optical response characteristics of these devices have been examined at both dc and microwave frequencies. The microwave response, at frequencies to 8 GHz, was studied by illuminating the devices with the output of an internally modulated GaAlAs diode laser. Results of these measurements are presented and compared with that of GaAs photoconductors.
Topics: SCANNERS, SENSORS, SKY, SPIN, EARTH (PLANET), LOW EARTH ORBITS, MOON, SPACECRAFT MOTION, SUN
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185
Jul 26, 2010
07/10
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Cline, Nea
texts
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The Master Directory, which is overview information about whole data sets, is outlined. The data system environment is depicted. The question is explored of what is a prototype international directory including purpose and features. Advantages of on-line directories are listed. Interconnected directory assumptions are given. A description of given of DIF (Directory Interchange Format), which is an exchange file for directory information, along with information content of DIF and directories....
Topics: CLOUD PHYSICS, STORMS, EARTH ORBITS, EXPLOITATION, GEOSYNCHRONOUS ORBITS, LOW EARTH ORBITS, OCEANS,...
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205
Jun 13, 2011
06/11
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Consiglio, Maria; Williams, Daniel; Murdoch, Jennifer; Adams, Catherin
texts
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A human-in-the-loop simulation experiment was conducted at the NASA Langley Research Center s (LaRC) Air Traffic Operations Lab (ATOL) in an effort to comprehensively validate tools and procedures intended to enable the Small Aircraft Transportation System, Higher Volume Operations (SATS HVO) concept of operations. The SATS HVO procedures were developed to increase the rate of operations at non-towered, non-radar airports in near all-weather conditions. A key element of the design is the...
Topics: DEGRADATION, GROUND TESTS, INTERNATIONAL SPACE STATION, LOW EARTH ORBITS, TEST FACILITIES,...
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366
Jun 3, 2011
06/11
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Cooper, Ke
texts
eye 366
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Over the last decade, rapid prototyping (RP) technologies have continued to advance in all aspects of operation and application. From continuously advanced materials and processes development to more hard-core manufacturing uses, the RP realm has stretched considerably past its original expectations as a prototyping capability. This paper discusses the unique applications for which NASA has chosen these manufacturing techniques to be utilized in outer space.
Topics: CARGO, INTERNATIONAL SPACE STATION, LOGISTICS, LAUNCH VEHICLES, LOW EARTH ORBITS, LUNAR ORBITS,...
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278
Jul 12, 2010
07/10
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Cooper, L. P.; Vinopal, T. J.; Florence, D. E.; Michel, R. W.; Brown, J. R.; Bergeron, R. P.; Weldon, V. A
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VEHICLE/ENGINE Integration Issues are explored for orbit transfer vehicles (OTV's). The impact of space basing and aeroassist on VEHICLE/ENGINE integration is discussed. The AOTV structure and thermal protection subsystem weights were scaled as the vehicle length and surface was changed. It is concluded that for increased allowable payload lengths in a ground-based system, lower length-to-diameter (L/D) is as important as higher mixture ration (MR) in the range of mid L/D ATOV's. Scenario...
Topics: AEROASSIST, PROPULSION SYSTEM PERFORMANCE, GEOSYNCHRONOUS ORBITS, LIFT DRAG RATIO, ORBIT TRANSFER...
241
241
May 28, 2011
05/11
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Cui, Zhenqia
texts
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In this thesis, we analyze various factors that affect quality of service (QoS) communication in high-speed, packet-switching sub-networks. We hypothesize that sub-network-wide bandwidth reservation and guaranteed CPU processing power at endpoint systems for handling data traffic are indispensable to achieving hard end-to-end quality of service. Different bandwidth reservation strategies, traffic characterization schemes, and scheduling algorithms affect the network resources and CPU usage as...
Topics: RADIATION DOSAGE, COMMUNICATION SATELLITES, EXTRATERRESTRIAL RADIATION, IONIZING RADIATION, LOW...
413
413
May 29, 2011
05/11
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Dankhoff, W.; Dayton, K.; Levack, D.; Odom, P.; Rhodes, R.; Robinson, J
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In response to a NASA request, the National Space Propulsion Synergy Team (SPST) team agreed to provide technical and programmatic support to NASA in formulating a Spaceliner 100 Technology Program. The SPST offered a broad cross-section of expertise and experience. Its membership consists of senior level, volunteer representatives from across government, industry, and academia. The purpose of this paper is to provide a summary of the SPST support of SL100, which culminated in a propulsion...
Topics: CHARGE COUPLED DEVICES, TELESCOPES, SUN, SOLAR RADIATION, SOLAR ARRAYS, NASA PROGRAMS, LOW EARTH...
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Jun 12, 2011
06/11
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DeWitt, Kenneth J
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The following section summarizes the impact of the Ohio Space Grant Consortium (OSGC) in Ohio and to NASA over the last four-year period (February 1, 2001 to April 30, 2005) and highlights the important accomplishments of the consortium. The strength of the OSGC network of universities, community colleges, government agencies, industry, and outreach affiliates is well-established and is growing. The OSGC Consortium Management Structure was designed and remains committed to using the talents and...
Topics: LITHIUM, SPACE MISSIONS, METAL IONS, LOW EARTH ORBITS, NASA PROGRAMS, LIFE (DURABILITY), TECHNOLOGY...
This research focused on improved spacecraft relative dynamics modeling and analysis, estimation of spacecraft relative motion, and control of spacecraft relative motion, with particular emphasis on estimation (i.e. navigation) of spacecraft relative trajectories from angles-only data.
Topics: DTIC Archive, Cicci,David A, Auburn University Auburn United States, artificial satellites, space...
The Naval Research Laboratory developed and launched the spherical SpinSat satellite to accomplish two primary goals: 1) study the performance of a new class of micro-thrusters, and 2) provide a calibrated drag experiment to characterize Earths upper atmosphere during the current period of relatively high solar activity. The 55.9 cm diameter aluminum sphere is equipped with a set of Electrically-Controlled Solid Propellant (ESP) thrusters, oriented to allow both translational and...
Topics: DTIC Archive, Hall,Doyle, Air Force Research Laboratory Maui United States, low earth orbits,...
Since the first space mission in 1957 (Sputnik 1), artificial objects of different size appeared in orbits around the Earth. Nowadays, the number of such objects is estimated to be over 2 millions. More than 300000 of them have a size greater than 10 cm although only 5% of them are catalogued. The observation and tracking of Resident Space Objects (RSOs) has become a crucial task in launch planning of new satellites, collisions-avoidance operations and in general to ensure the safety of...
Topics: DTIC Archive, Martorella,Marco, UNIVERSITY DI PISA, DEPARTMENT DI INGEGNERIA PISA Italy, space...
This paper examines Chinas growing military space program to assess if it is a threat to the national security interests of the United States. There are four possible space doctrines or combinations thereof that China can pursue space sanctuary, survivability, control, and/or high-ground (dominance). Chinese pursuit of either of the latter two would pose a security threat to the United States. This paper assesses which doctrine China is pursuing based on recent Chinese space activities, Chinese...
Topics: DTIC Archive, Wulff,Timothy R, Air War College Air University Maxwell AFB United States, china,...
This study explores the influence of norms governing state behavior in outer space. While the US currently enjoys a preponderance of presence in outer space, and is thus the most influential state within the space medium, this lead has been eroding as more states actively participate in space. At a time of soaring national debt and shrinking military budgets, this thesis looks at ways the US can maintain its lead and protect its investment in space. While kinetic weaponization of space offers...
Topics: DTIC Archive, Long,Patrick V, Air University School of Advanced Air and Space Studies Maxwell AFB...
Orbital altitudes congested with spacecraft and debris combined with recent collisions have all but negated the Big Sky Theory. As the sheer number of orbital objects to track grows unbounded so does interest in prediction methods that are rapid and minimally computational. Claimed as the \other solvable solution, the recently completed solution too orbital motion about the earth, based on Vinti's method and including the major effects of the equatorial bulge, opens up the prospect of much more...
Topics: DTIC Archive, Wright,Steven P, Air Force Institute of Technology Wright-Patterson Air Force Base,...
Space capabilities are vital to United States national power, commerce, science, and prestige. These capabilities will grow even more vital to the United States and the global economy by 2035. What will the space technology and operating environment look like in 2035? Technology trends in two fundamental areas -- spacecraft and space transportation -- indicate space technologies, capabilities, products, and services will become far more affordable, ubiquitous, globally available, and...
Topics: DTIC Archive, Buck,Darren J, Air War College Air University Maxwell AFB United States, space...
Cadet Joseph Shields argues the merits of weaponizing space.
Topics: DTIC Archive, Shields,Joseph, AIR FORCE ACADEMY COLORADO SPRINGS CO COLORADO SPRINGS United States,...
This report provides a summary of the work carried out in the second year of the SOARD project, Grant No. FA9550-15-1-0069, devoted to the investigation and improvement of the detection and tracking methods of inactive Resident Space Objects (RSOs). In the second year, a Random Finite Set (RFS) based Joint Target Detection and Tracking lter was evaluated for the space object tracking scenarios and two extensions were developed in order to increase their robustness to unknown detection...
Topics: DTIC Archive, Adams,Martin, Universidad de Chile Santiago Chile, artificial satellites, space...
Particle swarm optimization is used to generate an initial guess for designing fuel-optimal trajectories in multiple dynamical environments. Trajectories designed in the vicinity of Earth use continuous or finite low-thrust burning and transfer from an inclined or equatorial circular low-Earth-orbit to a geostationary orbit. In addition, a trajectory from near-Earth to a periodic orbit about the cislunar Lagrange point with minimized impulsive burn costs is designed within a multi-body...
Topics: DTIC Archive, Zurita,Alfredo Jr G, AIR FORCE INSTITUTE OF TECHNOLOGY WRIGHT-PATTERSON AFB OH...
This work contains the definition of the initial orbit determination (IOD) method with some first results, a literature review about the Manifold, the creation of the algorithms and architecture for the ADS and the initial merging of the ADS into the IOD technique. The IOD algorithm is explained, implemented and comparisons with results from literature are also outlined. In specific it takes as input optical observations and gives as output the state of the object at the central time of...
Topics: DTIC Archive, Di Lizia,Pierluigi, POLITECNICO DI MILANO MILANO Italy, SPACE SITUATIONAL AWARENESS,...
Orbital space debris can be defined as dead satellites, discarded rocket parts, or simply flecks of paint or other small objects orbiting the earth. It is simply space junk, but junk that can be extremely dangerous to space assets. Most of the debris concerns are associated with satellites and manned space missions in Low-Earth orbit (LEO). LEO extends out to about 5,000 kilometers from the earths equator.1 There are two other bands of orbits that contain satellites. The first,...
Topics: DTIC Archive, Donahue,Jack, Air Command and Staff College Maxwell Air Force Base United States,...
The circular restricted three-body problem (CR3BP) is a simplified dynamical model for a satellite under the gravitational influence of both the Earth and the Moon, maintaining closer fidelity to the gravitational environment experienced by a high-altitude Earth-orbiting spacecraft than modeling in the Earth-satellite two-body problem. Resonant orbit arcs are used to determine an initial guess to input into an algorithm that computes a trajectory solution with specific design requirements and...
Topics: DTIC Archive, Wilmer,Meredith M, AIR FORCE INSTITUTE OF TECHNOLOGY WRIGHT-PATTERSON AFB OH...
This research developed a methodology for determining the required accuracy of the dynamic model based on system requirements, the relative navigation accuracy and thruster accuracy. A state transition matrix was developed to propagate satellite relative motion to include non-conservative forces and the effect of higher order gravitational terms. The models developed were validated using numerical simulations.
Topics: DTIC Archive, Alfriend,Kyle T, TEXAS ENGINEERING EXPERIMENT STATION COLLEGE STATION COLLEGE STATION...
We report on AFOSR-sponsored research titled Investigation of Ionospheric Turbulence and Whistler Wave Interactions with Space Plasmas(FA9550-09-1-0391 for the period of June 1, 2009 August 31, 2012). It includes two parts: (1) naturally occurring and radio wave-induced large-and medium-scale ionospheric turbulence, and (2) whistler wave-generated short-scale ionospheric turbulence. Two types of large- and medium-scale ionospheric turbulence are discussed separately, viz., (a) anomalous heat...
Topics: DTIC Archive, Lee,Min-Chang, Department of Electrical and Computer Engineering, Boston University...
This research investigates the effect of naturally induced Lorentz force perturbations on the orbital evolution of near Earthspace objects. Natural charging of all space objects occurs in the natural space plasma environment. The charging levels are dependent on the local plasma environment, the (surface) materials of the space object and its geometry (capacitance). When the charge is moving relative to the Earth magnetosphere, Lorentz forces are induced. The Lorentz forces are in turn an...
Topics: DTIC Archive, Frueh,Carolin, Purdue University West Lafayette United States, space objects, Lorentz...
This report describes a method for predicting proton flux in low earth orbit (LEO) during a solar proton event (SPE). In particular, integral fluxes of 5 and 30 MeV protons are required, though it can be applied equally to other energy ranges. The method depends on a geomagnetic cutoff model, proton measurements from a geosynchronous (GEO) GOES satellite, and the geomagnetic Kp index. Its limitations and statistical accuracy are also described. The recommended cutoff model is empirical. Its...
Topics: DTIC Archive, Selesnick,Richard S, Air Force Research Laboratory, Space Vehicles Directorate...
Since the launch of Sputnik in 1957, space has been transformed from a mostly serene environment to one bustling with activity. The past five decades have witnessed a global growth in reliance on space capabilities and a corresponding increase in the number of man-made objects in orbit. The capabilities and missions performed from space have proliferated in both sophistication and complexity. In addition, threats to on-orbit assets are also on the rise. These factors all point to the need for...
Topics: DTIC Archive, Ackerman,Edward T, Air War College Air University Maxwell AFB United States, space...
While effects-based operations and thinking have created significant debate, joint doctrine focuses on effects as an element of operational design rather than the many variations of effects-based operations theory. There is a critical relationship among desired effects, critical vulnerabilities, and military means. The Joint Force Commanders ability to create desired effects against an adversary's critical vulnerabilities (in order to attack the enemy's center of gravity) using military means...
Topics: DTIC Archive, Stevens,David L, AIR COMMAND AND STAFF COLLEGE, AIR UNIVERSITY Maxwell Air Force Base...
Nanosatellites provide a light, efficient, and cost-effective way for research institutions to carry out experiments in low Earth orbit. These satellites frequently use the ultra-high and very high frequency bands to transfer their data to the ground stations, and oftentimes will use internet protocol and Transmission Control Protocol as a standard for communication to ensure the arrival and integrity of the data transmitted. Due to bandwidth limitations and signal noise, these connection-based...
Topics: DTIC Archive, Banuelos,Cervando II A, Naval Postgraduate School Naval Postgraduate School United...
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368
Sep 20, 2010
09/10
by
Dellacorte, Christopher; Deadmore, Daniel L
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The indentation microhardness of stoichiometric and reduced single crystal rutile (TiO2) from 25 to 800 C is presented in this paper. The results serve two main purposes. One is to assess the effect of rutile's stoichiometry on its hardness. The other is to test recently suggested theory on solid lubrication with sub Stoichiometric rutile in an effort to better understand shear controlled phenomenon. Microhardness was measured using a Vickers diamond indentor on both vacuum and hydrogen reduced...
Topics: CODERS, DOWNLINKING, HARDWARE, LOW EARTH ORBITS, METEOROLOGICAL INSTRUMENTS, COMPRESSION RATIO,...
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367
Sep 20, 2010
09/10
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Dominey, L. A.; Goldman, J. L.; Koch, V. R
texts
eye 367
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During the second year of research under NASA SBIR Contract NAS7-967, Covalent Associates and NASA contract monitors at the Jet Propulsion Laboratory agreed to perform an evaluation of the three best electrolytes developed during Phase 2. Due to the extensive period of time required to collect meaningful cycling data, we realized the study would extend well beyond the original formal end of the Phase 2 program (August 31, 1988). The substitution of this effort in lieu of an earlier proposed...
Topics: EARTH ORBITAL ENVIRONMENTS, LOW EARTH ORBITS, METALS, OPTICAL MATERIALS, POLYMER MATRIX COMPOSITES,...
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May 22, 2011
05/11
by
Dudkin, V. E.; Kovalev, E. E.; Nefedov, N. A.; Antonchik, V. A.; Bogdanov, S. D.; Kosmach, V. F.; Likhachev, A. YU.; Benton, E. V.; Crawford, H. J
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A method is proposed for finding the dependence of mean multiplicities of secondaries on the nucleus-collision impact parameter from the data on the total interaction ensemble. The impact parameter has been shown to completely define the mean characteristics of an individual interaction event. A difference has been found between experimental results and the data calculated in terms of the cascade-evaporation model at impact-parameter values below 3 fm.
Topics: DATA BASES, DATA PROCESSING, EXTRATERRESTRIAL RADIATION, LONG DURATION EXPOSURE FACILITY,...
