The results are presented for a NASA Phase 1 study conducted from mid 1987 through mid 1989 at Ames Research Center. The Centrifuge Facility is the major element of the biological research facility for the implementation of NASA's Life Science Research Program on Space Station Freedom using non-human specimens (such as small primates, rodents, plants, insects, cell tissues). Five systems are described which comprise the Facility: habitats, holding units, centrifuge, glovebox, and service unit....
Topics: NASA Technical Reports Server (NTRS), DESIGN ANALYSIS, FUNCTIONAL DESIGN SPECIFICATIONS, HABITATS,...
Future launch systems of the United States will require improvements in booster safety, reliability, and cost. In order to increase payload capabilities, performance improvements are also desirable. The hybrid rocket motor (HRM) offers the potential for improvements in all of these areas. The designs are presented for two sizes of hybrid boosters, a large 4.57 m (180 in.) diameter booster duplicating the Advanced Solid Rocket Motor (ASRM) vacuum thrust-time profile and smaller 2.44 m (96 in.),...
Topics: NASA Technical Reports Server (NTRS), ENGINE DESIGN, FUEL SYSTEMS, HYBRID PROPULSION, NOZZLE...
Metallized propellants are liquid propellants with a metal additive suspended in a gelled fuel or oxidizer. Typically, aluminum (Al) particles are the metal additive. These propellants provide increase in the density and/or the specific impulse of the propulsion system. Using metallized propellant for volume-and mass-constrained upper stages can deliver modest increases in performance for low earth orbit to geosynchronous earth orbit (LEO-GEO) and other earth orbital transfer missions....
Topics: NASA Technical Reports Server (NTRS), ADVANCED LAUNCH SYSTEM (STS), GELLED PROPELLANTS, INERTIAL...
The Department of Materials Science and Engineering (MSE) is investigating the use of monatomic chlorine produced in a cold plasma to recover oxygen and metallurgically significant metals from lunar materials. Development of techniques for the production of the chlorine radical (and other energetic radicals for these processes) using local planetary resources is a key step for a successful approach. It was demonstrated terrestrially that the use of UV light to energize the photogeneration of OH...
Topics: NASA Technical Reports Server (NTRS), CHLORINATION, COLD PLASMAS, FREE RADICALS, LUNAR RESOURCES,...
Applying ITS technology to the shuttle diagnostics would not require the rigor of the Petri Net representation, however it is important in providing the animated simulated portion of the interface and the demands placed on the system to support the training aspects to have a homogeneous and consistent underlying knowledge representation. By keeping the diagnostic rule base, the hardware description, the software description, user profiles, desired behavioral knowledge, and the user interface in...
Topics: NASA Technical Reports Server (NTRS), COMPUTER PROGRAMS, COMPUTER SYSTEMS PERFORMANCE, KNOWLEDGE...
The objectives are: to analyze dual polarization lidar measurements of aerosols and polar stratospheric clouds (PSCs) obtained aboard the NASA Ames DC-8 aircraft during the 1989 Airborne Arctic Stratospheric Expedition (AASE); and to combine lidar, SAM II, and other AASE data with theoretical modeling calculations to study PSC characteristics. A summary of progress and results is given.
Topics: NASA Technical Reports Server (NTRS), AEROSOLS, ICE CLOUDS, MATHEMATICAL MODELS, OPTICAL RADAR,...
A new technique is presented for the three dimensional recognition of symmetric objects from range images. Beginning from the implicit representation of quadrics, a set of ten coefficients is determined for symmetric objects like spheres, cones, cylinders, ellipsoids, and parallelepipeds. Instead of using these ten coefficients trying to fit them to smooth surfaces (patches) based on the traditional way of determining curvatures, a new approach based on two dimensional geometry is used. For...
Topics: NASA Technical Reports Server (NTRS), COEFFICIENTS, CURVATURE, PATTERN RECOGNITION, RANGEFINDING,...
This design development effort addressed significant technical issues concerning the use and benefits of high strain composite wing structures (Epsilon(sub ult) = 6000 micro-in/in) for future Navy aircraft. These issues were concerned primarily with the structural integrity and durability of the innovative design concepts and manufacturing techniques which permitted a 50 percent increase in design ultimate strain level (while maintaining the same fiber/resin system) as well as damage tolerance...
Topics: NASA Technical Reports Server (NTRS), AIRCRAFT DESIGN, COMPOSITE STRUCTURES, FABRICATION, FIBER...
The declining pool of graduates, the lack of rigorous preparation in science and mathematics, and the declining interest in science and engineering careers at the precollege level promises a shortage of technically educated personnel at the college level for industry, government, and the universities in the next several decades. The educational process, which starts out with a large number of students at the elementary level, but with an ever smaller number preparing for science and engineering...
Topics: NASA Technical Reports Server (NTRS), AEROSPACE ENGINEERING, AEROSPACE SCIENCES, EDUCATION,...
The characteristics of double layers observed by researchers investigating magnetospheric phenomena are contrasted to those observed in plasma contacting experiments. Experiments in the electron collection mode of the plasma contacting process were performed and the results confirm a simple model of this process for current levels ranging to 3 A. Experimental results were also obtained in a study of the process of electron emission from a hollow cathode plasma contactor. High energy ions are...
Topics: NASA Technical Reports Server (NTRS), ELECTRON DENSITY (CONCENTRATION), ELECTRON EMISSION, HOLLOW...
In direct response to Request for Proposals: Flight at very low Reynolds numbers - a station keeping mission, the members of Design Squad E present Project Dawdler: a remotely-piloted airplane supported by an independently controlled take-off cart. A brief introduction to Project Dawdler's overall mission and design, is given. The Dawdler is a remotely-piloted airplane designed to fly in an environmentally-controlled closed course at a Reynolds number of 10(exp 5) and at a cruise velocity of 25...
Topics: NASA Technical Reports Server (NTRS), CANARD CONFIGURATIONS, CLIMBING FLIGHT, LOW REYNOLDS NUMBER,...
Reduced-order models are considered in the context of parameter adaptive controllers for tracking workspace trajectories. A dual-arm manipulation task is used to illustrate the methodology and provide simulation results. A parameter adaptive controller is designed to track the desired position trajectory of a payload using a four-parameter model instead of a full-order, nine-parameter model. Several simulations with different payload-to-arm mass ratios are used to illustrate the capabilities of...
Topics: NASA Technical Reports Server (NTRS), ADAPTIVE CONTROL, COMPLEX SYSTEMS, CONTROL SYSTEMS DESIGN,...
An architecture is presented for controlling robots that have multiple tasks, operate in dynamic domains, and require a fair degree of autonomy. The architecture is built on several layers of functionality, including a distributed communication layer, a behavior layer for querying sensors, expanding goals, and executing commands, and a task level for managing the temporal aspects of planning and achieving goals, coordinating tasks, allocating resources, monitoring, and recovering from errors....
Topics: NASA Technical Reports Server (NTRS), ARCHITECTURE (COMPUTERS), CONTROL SYSTEMS DESIGN,...
Two interdisciplinary facilities that have been proposed for the Space Station, the Gas-Grain Simulation Facility and the Cosmic Dust Collector Facility, are reviewed. Both of these facilities provide opportunities for scientists interested in carbon related research to perform experiments in earth orbit.
Topics: NASA Technical Reports Server (NTRS), COSMIC DUST, DUST COLLECTORS, MICROGRAVITY, SIMULATORS, SPACE...
The need to increase engineering productivity and decrease software life cycle costs in real-time system development establishes a motivation for a method of rapid prototyping. The design by iterative rapid prototyping technique is described. A tool which facilitates such a design methodology for the generation of embedded control software is described.
Topics: NASA Technical Reports Server (NTRS), ADA (PROGRAMMING LANGUAGE), COMPUTER PROGRAMMING, CONTROL...
The high-temperature superconductivity is explained widely by the layered crystal structure. The one- and two-dimensional subsystems and their interaction are investigated here. It is assumed that the high-T(sub c) superconductivity takes place in the two-dimensional subsystem and the increase of the phase transition temperature from 60 K up to 90 K is the consequence of turning on the influence of one-dimensional chains. The interaction between the two subsystems is transferred along the c...
Topics: NASA Technical Reports Server (NTRS), CRYSTAL STRUCTURE, CRYSTALS, ELASTIC PROPERTIES,...
Green's functions are derived for the plane elastostatics problem of a dislocation in a bimaterial strip. Using these fundamental solutions as kernels, various problems involving cracks in a bimaterial strip are analyzed using singular integral equations. For each problem considered, stress intensity factors are calculated for several combinations of the parameters which describe loading, geometry and material mismatch.
Topics: NASA Technical Reports Server (NTRS), BENDING, BRITTLE MATERIALS, COMPOSITE MATERIALS, CRACK...
The chemistry, hydroxyapatite crystal size, and maturation of the bone and dentin is characterized in rats exposed to microgravity for 12.5d in a Soviet Biosatellite (Cosmos-1887). Calvarial and vertebral bone ash was subnormal, but contained a normal percent composition of Ca, P, and Mg. These tissues varied from the norm by having lower Ca/P and higher Ca/Mg ratios than any of their age-matched controls (Vivarium and Synchronous Groups). Gradient density analyses (calvaria) indicated a strong...
Topics: NASA Technical Reports Server (NTRS), BONE MINERAL CONTENT, BONES, GRAVITATIONAL EFFECTS,...
The increased complexity of test operations and customer requirements at Langley Research Center's National Transonic Facility (NTF) surpassed the capabilities of the initial realtime graphics system. The analysis of existing hardware and software and the enhancements made to develop a new realtime graphics system are described. The result of this effort is a cost effective system, based on hardware already in place, that support high speed, high resolution, generation and display of multiple...
Topics: NASA Technical Reports Server (NTRS), COMPUTER GRAPHICS, COMPUTER PROGRAMS, COMPUTER SYSTEMS...
A selection of successes and failures of Computational Fluid Dynamics (CFD) is discussed. Experiment/CFD correlations involving full potential and Euler computations of the aerodynamic characteristics of four commercial transport wings and two low aspect ratio, delta wing configurations are shown. The examples consist of experiment/CFD comparisons for aerodynamic forces, moments, and pressures. Navier-Stokes equations are not considered.
Topics: NASA Technical Reports Server (NTRS), AERODYNAMIC CHARACTERISTICS, AERODYNAMIC CONFIGURATIONS,...
A conceptual Hypersonic Business Jet (HyBuJet) was examined. The main areas of concentration include: aerodynamics, propulsion, stability and control, mission profile, and atmospheric heating. In order to optimize for cruise conditions, a waverider configuration was chosen for the high lift drag ratio and low wave drag. The leading edge and lower surface of a waverider was mapped out from a known flow field and optimized for cruising at Mach 6 and at high altitudes. The shockwave generated by a...
Topics: NASA Technical Reports Server (NTRS), AERODYNAMIC CONFIGURATIONS, AIRCRAFT DESIGN, CONTROL...
Delamination in the form of cracking or separation between plies in an advanced fiber composite laminate is a problem of major concern. Both advanced analytical methods and advanced computational analyses are conducted to: (1) develop an asymptotic solution for a composite laminate subject to out-of-plane bending; (2) construct advanced singular finite elements in conjunction with the development of nonsingular elements for this bending problem; and (3) evaluate the delamination failure...
Topics: NASA Technical Reports Server (NTRS), BENDING, COMPUTERIZED SIMULATION, DELAMINATING, ELASTIC...
The goals of the workshop were first to provide scientists an opportunity to acquaint themselves with the past, current, and future scientific investigations carried out in the Containerless Science programs of the Microgravity Science and Applications Div. of NASA, as well as ESA and Japanese Space Agencies. The second goal was to assess the technological development program for low gravity containerless experimentation instruments. The third goal was to obtain recommendations concerning...
Topics: NASA Technical Reports Server (NTRS), CONFERENCES, CONTAINERLESS MELTS, MICROGRAVITY, MICROGRAVITY...
Flight motor set 360T010 was launched at approximately 7:34 a.m. CST (090:114:12:33:50.990 GMT) on 24 Apr. 1990 after one launch attempt (attempt on 10 Apr. 1990 was scrubbed following an indication of erratic operation of the Orbiter No. 1 Auciliary Power Unit No. 1). There were no problems with the solid rocket motor launches, overall motor performance was excellent. There were no debris concerns from either motor. Nearly all ballistic contract end item specification parameters were verified...
Topics: NASA Technical Reports Server (NTRS), ANOMALIES, HEATERS, IGNITERS, IGNITION, INSPECTION,...
A model for addressing navigation limitations and metacognitive constraints in hypermedia training systems is presented in the form of the viewgraphs. The following subject areas are covered: samples of software and people problems; system design; and hypermedia training system.
Topics: NASA Technical Reports Server (NTRS), COGNITION, EDUCATION, LEARNING, NAVIGATION, EXPERT SYSTEMS,...
A ring shaped grid of photovoltaic solar collectors encircling a lunar pole at 80 to 85 degrees latitude is proposed as the primary research, development, and construction goal for an initial lunar base. The polar Lunar Power Ring (LPR) is designed to provide continuous electrical power in ever increasing amounts as collectors are added to the ring grid. The LPR can provide electricity for any purpose indefinitely, barring a meteor strike. The associated rail infrastructure and inherently...
Topics: NASA Technical Reports Server (NTRS), ELECTRICITY, LUNAR BASES, PROPULSION, RESEARCH FACILITIES,...
CO2 comprises 95 pct. of the composition of the Martian atmosphere. However, the Martian atmosphere also has a high aerosol content. Dust particles vary from less than 0.2 to greater than 3.0. CO2 is an active absorber and emitter in near IR and IR wavelengths; the near IR absorption bands of CO2 provide significant heating of the atmosphere, and the 15 micron band provides rapid cooling. Including both CO2 and aerosol radiative transfer simultaneously in a model is difficult. Aerosol radiative...
Topics: NASA Technical Reports Server (NTRS), ABSORPTION SPECTRA, AEROSOLS, CARBON DIOXIDE, INFRARED...
New and sharp estimates are derived for the growth in the complex plane of polynomials known to have a curved majorant on a given ellipse. These so-called Bernstein type inequalities are closely connected with certain constrained Chebyshev approximation problems on ellipses. Also presented are some new results for approximation problems of this type.
Topics: NASA Technical Reports Server (NTRS), CHEBYSHEV APPROXIMATION, ELLIPSES, INEQUALITIES, POLYNOMIALS,...
The growth in cost and importance of software to NASA has caused NASA to address the improvement of software development across the agency. One of the products of this program is a series of guidebooks that define a NASA concept of the assurance processes that are used in software development. The Software Assurance Guidebook, NASA-GB-A201, issued in September, 1989, provides an overall picture of the NASA concepts and practices in software assurance. Second level guidebooks focus on specific...
Topics: NASA Technical Reports Server (NTRS), COMPUTER PROGRAMS, COSTS, HANDBOOKS, SOFTWARE RELIABILITY,...
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71
May 16, 2014
05/14
by
Vince Lutterbie
texts
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Vince Lutterbie, master of the awesome PoolCon, published this game zine.
Topics: diplomacy, dippy, zine, fanzine, dipzine
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37
texts
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23 v. : 25-28 cm
Topics: Forest fires Prevention and control Periodicals, Forest reserves Fire management Periodicals,...
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76
Jul 30, 2015
07/15
by
Mark Linde
movies
eye 76
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Featuring the Foxboro High School Jazz Workshop Combo, Jazz Choir, Select Vocal Jazz Ensemble, and Concert Band.
Topic: 02035
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49
May 28, 2019
05/19
by
The Government of the Hellenic Republic
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Topics: Greek Government Gazette, Greece, official journal, Part 3, FEK, ΦΕK, Εφημερίδα της...
Aired August 1990. From VHS
Topic: australia, commercial, 90s
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3.0
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37
Apr 1, 2010
04/10
by
Relief Society (Church of Jesus Christ of Latter-day Saints)
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Spine title: Relief Society personal study guide 2
Topics: Spiritual life, Mormon doctrine
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19
Aug 14, 2019
08/19
by
Madrid, Juan, 1947-
texts
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115
Apr 28, 2010
04/10
by
Cohlene, Terri, 1950-; Reasoner, Charles
texts
eye 115
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Retells the legend of Ka-ha-si, who acquires great strength and boldness and uses them to rescue his people in times of peril. Includes information on the customs and lifestyle of the Eskimos
Topics: Eskimos, Indians of North America
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3.0
texts
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v. : 23 cm
Topic: Canada -- History -- Periodicals
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17
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v. : 23 cm
Topic: Canada -- History -- Periodicals
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9.0
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v. : 23 cm
Topic: Canada -- History -- Periodicals
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37
Jun 3, 2010
06/10
by
Claessens, Sharon
texts
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"Kitchen nutrition cooking system"--Cover
Topic: Cookery
The Granite City Press-Record was a newspaper that covered Granite City, Illinois and surrounding communities. Uploaded by the Six Mile Regional Library District with express written consent of Lee Enterprises.
Topics: Granite City, Illinois, newspaper, Pontoon Beach, Mitchell, Madison, Venice
The concept of pressure proof testing of fuselage structures with fatigue cracks to insure structural integrity was evaluated from a fracture mechanics viewpoint. A generic analytical and experimental investigation was conducted on uniaxially loaded flat panels with crack configurations and stress levels typical of longitudinal lap splice joints in commercial transport aircraft fuselages. The results revealed that the remaining fatigue life after a proof test was longer than that without the...
Topics: NASA Technical Reports Server (NTRS), CRACK PROPAGATION, CRACKS, FATIGUE LIFE, FRACTURE MECHANICS,...
The objective of this experiment is to provide a simple, inexpensive composite fabrication technique which can be easily performed with a minimum of equipment and facilities. This process eliminates expensive female molds and uses only male molds which are easily formed from foam blocks. Once the mold is shaped, it is covered with fiberglass and becomes a structural component of the product.
Topics: NASA Technical Reports Server (NTRS), COMPOSITE MATERIALS, CUTTERS, CUTTING, FABRICATION, FOAMS,...
The problem of en route aircraft noise was examined in a formal, dedicated, setting. Whereas the general meaning of the term en route might be intuitively understood, it is suggested that a precise formal definition of the term en route would be opportune from the outset, especially since the scientific and technical investigation of the problem of noise immissions on the ground from aircraft in flight away from the airspace of an airport may conceivably lead to administrative, regulatory, and...
Topics: NASA Technical Reports Server (NTRS), AIRCRAFT NOISE, AIRSPACE, ENVIRONMENT POLLUTION, NOISE...
In order to accurately test the AX-5 space suit, a complex series of motions needed to be performed which provided a unique opportunity for mechanism design. The cycle life machine design showed how 3-D computer images can enhance mechanical design as well as help in visualizing mechanisms before manufacturing them. In the early stages of the design, potential problems in the motion of the joint and in the four bar linkage system were resolved using CAD. Since these problems would have been...
Topics: NASA Technical Reports Server (NTRS), CYCLIC LOADS, FATIGUE (MATERIALS), JOINTS (JUNCTIONS),...
A desire for fresh vegetables for consumption during long term space missions has been foreseen. To meet this need in a microgravity environment within the limited space and energy available on Space Station requires highly productive vegetable cultivars of short stature to optimize vegetable production per volume available. Special water and nutrient delivery systems must also be utilized. As a first step towards fresh vegetable production in the microgravity of Space Station, several...
Topics: NASA Technical Reports Server (NTRS), FARM CROPS, GREENHOUSE EFFECT, MICROGRAVITY, PLANTING,...
Distributed application management consists of monitoring and controlling an application as it executes in a distributed environment. It encompasses such activities as configuration, initialization, performance monitoring, resource scheduling, and failure response. The Meta system is described: a collection of tools for constructing distributed application management software. Meta provides the mechanism, while the programmer specifies the policy for application management. The policy is...
Topics: NASA Technical Reports Server (NTRS), APPLICATIONS PROGRAMS (COMPUTERS), ARCHITECTURE (COMPUTERS),...
