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7.0
movies
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Topics: tagesschau, Evening News, Germany
Topics: tagesschau, Evening News, Germany
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7.0
movies
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Topics: tagesschau, Evening News, Germany
16
16
Jan 17, 2015
01/15
by
Mount Wilson Observatory
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This image includes data from the synoptic program at the 150-Foot Solar Tower of the Mt. Wilson Observatory. The Mt. Wilson 150-Foot Solar Tower is operated by UCLA, with funding from NASA, ONR and NSF, under agreement with the Mt. Wilson Institute.
Topics: solar, activity, sun, drawing, wilson
Note : Blurred, faded, or ripped text inherent to original newspaper / microfilm.
Topics: californiarevealed, Newspaper--Local editions, Local history, California--Newspapers, Newspapers,...
Source: Microfilm: 1 Reel of 1 (Unknown)
48
48
Apr 23, 2016
04/16
by
TechNation
audio
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Internet Multicasting Service Series: TechNation Program: Life in the Technology Age Dr. Moira Gunn speaks with Tony Smith, author of "Parzival’s Briefcase -- Six Practices and a New Philosophy for Healthy Organizational Change." Through the medieval legend of the knight Parzival, Dr. Smith likens our journeys in the technology age to the difficulties of Parzival’s search for the Holy Grail. They discuss the nature of technology organizations and maintaining your personal balance...
Topics: Internet Talk Radio, TechNation
Multi Print Vol 1.0 (1993 11 05)(Assassins, The)(PD)[o]
McGill University Library
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169
Aug 26, 2015
08/15
by
McGill University, Daily Publications Society,,
texts
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Topics: McGill University -- Students -- Newspapers., Universities and colleges -- Québec (Province) --...
McGill University Library
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Aug 26, 2015
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McGill University, Daily Publications Society,,
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Topics: McGill University -- Students -- Newspapers., Universities and colleges -- Québec (Province) --...
McGill University Library
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08/15
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McGill University, Daily Publications Society,,
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Topics: McGill University -- Students -- Newspapers., Universities and colleges -- Québec (Province) --...
An IC controller for a brushless motor includes commutation logic and an inverter on a single chip. The chip can also include an isolated power supply.
Topics: NASA Technical Reports Server (NTRS), CHIPS (ELECTRONICS), DIRECT CURRENT, CONTROLLERS, PATENTS,...
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Sep 11, 2014
09/14
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NCAA
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175
175
Dec 11, 2021
12/21
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The Sales Curve
software
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Topics: Abandonware, Game Boy, Super Nintendo Entertainment System, Sega CD, Sega Genesis/Mega Drive,...
Footage from the Seattle Water Department showing water tanks and reservoirs in West Seattle, including the Myrtle Reservoir and the West Seattle Reservoir. Item 8298, Record Series 3902-01, Seattle Municipal Archives Digitization of this videotape material has been made possible in part by a grant from the National Historical Publications and Records Commission.
Topic: Seattle Municipal Archives
The goal of this research is to experimentally characterize the behavior of droplets in vaporizing liquid sprays under conditions typical of those encountered in high pressure combustion systems such as liquid fueled rocket engines. Of particular interest are measurements of droplet drag, droplet heating, droplet vaporization, droplet distortion, and secondary droplet breakup, under both subcritical and supercritical conditions. The paper presents a brief description of the specific...
Topics: NASA Technical Reports Server (NTRS), DROPS (LIQUIDS), LIQUID PROPELLANT ROCKET ENGINES, PARTICLE...
The most common material system currently used for low thrust, radiation-cooled rockets is a niobium alloy (C-103) with a fused silica coating (R-512A or R-512E) for oxidation protection. However, significant amounts of fuel film cooling are usually required to keep the material below its maximum operating temperature of 1370 C, degrading engine performance. Also the R-512 coating is subject to cracking and eventual spalling after repeated thermal cycling. A new class of high-temperature,...
Topics: NASA Technical Reports Server (NTRS), IRIDIUM, OXIDATION RESISTANCE, PROTECTIVE COATINGS, RADIATION...
A 3.5 inch rabbit-ear-terminal nickel-hydrogen cell was designed and tested to deliver high capacity at steady discharge rates up to and including a C rate. Its specific energy yield of 60.6 wh/kg is believed to be the highest yet achieved in a slurry-process nickel-hydrogen cell, and its 10 C capacity of 113.9 AH the highest capacity yet of any type in a 3.5 inch diameter size. The cell also demonstrated a pulse capability of 180 amps for 20 seconds. Specific cell parameters and performance...
Topics: NASA Technical Reports Server (NTRS), ELECTRODES, FADING, NICKEL HYDROGEN BATTERIES, SWELLING,...
Individual pressure vessel (IPV) nickel-hydrogen technology was advanced at NASA Lewis and under Lewis contracts. Some of the advancements are as follows: to use 26 percent potassium hydroxide electrolyte to improve cycle life and performance, to modify the state of the art cell design to eliminate identified failure modes and further improve cycle life, and to develop a lightweight nickel electrode to reduce battery mass, hence reduce launch and/or increase satellite payload. A breakthrough in...
Topics: NASA Technical Reports Server (NTRS), ELECTRODES, ELECTROLYTES, NICKEL HYDROGEN BATTERIES,...
A Global Positioning System (GPS) flight receiver provides a means to precisely determine orbits for satellites in low to moderate altitude orbits. Above a 5000-km altitude, however, relatively few GPS satellites are visible. New approaches to orbit determination for satellites at higher altitudes could reduce DSN antenna time needed to provide navigation and orbit determination support to future missions. Modification of GPS ground receivers enables a beacon from the orbiter to be tracked...
Topics: NASA Technical Reports Server (NTRS), GEOSYNCHRONOUS ORBITS, GLOBAL POSITIONING SYSTEM, HIGH...
This study is devoted to a comparative analysis of three 'Adaptive ZOOM' (ZOom Overlapping Multi-level) methods based on similar concepts of hierarchical multigrid local refinement: LDC (Local Defect Correction), FAC (Fast Adaptive Composite), and FIC (Flux Interface Correction)--which we proposed recently. These methods are tested on two examples of a bidimensional elliptic problem. We compare, for V-cycle procedures, the asymptotic evolution of the global error evaluated by discrete norms,...
Topics: NASA Technical Reports Server (NTRS), COMPUTATIONAL GRIDS, CONVERGENCE, ELLIPTIC DIFFERENTIAL...
The final report for the Clearfield disassembly evaluation and a continuation of the KSC postflight assessment for the RSRM-28 (STS-53) RSRM flight set is presented. All observed hardware conditions were documented on PFOR's and are included in Appendices A through C. Appendices D and E contain the measurements and safety factor data for the nozzle and insulation components. This report, along with the KSC Ten-Day Postflight Hardware Evaluation Report (TWR-64215), represents a summary of the...
Topics: NASA Technical Reports Server (NTRS), BONDED JOINTS, NOZZLE DESIGN, POSTFLIGHT ANALYSIS, SOLID...
Prediction of whether a pressurized cylinder will fail catastrophically when impacted by a projectile has important applications ranging from perforation of an airplane's skin by a failed turbine blade to meteorite impact of a space station habitation module. This report summarizes the accomplishment of one task for a project whose aim is to simulate numerically the outcome of a high velocity impact of pressure vessels. A finite element patch covering the vicinity of a growing crack has been...
Topics: NASA Technical Reports Server (NTRS), CRACK PROPAGATION, CRACKS, FINITE ELEMENT METHOD, FRACTURING,...
A conjugate heat transfer computational fluid dynamics (CFD) model to describe regenerative cooling in the main combustion chamber and nozzle and in the injector faceplate region for a launch vehicle class liquid rocket engine was developed. An injector model for sprays which treats the fluid as a variable density, single-phase media was formulated, incorporated into a version of the FDNS code, and used to simulate the injector flow typical of that in the Space Shuttle Main Engine (SSME)....
Topics: NASA Technical Reports Server (NTRS), COMBUSTION CHAMBERS, COMPUTATIONAL FLUID DYNAMICS, HEAT...
The National Aeronautics and Space Administration is currently considering possible directions in Earth-to-orbit vehicle development under a study called 'Access to Space.' This agency-wide study is considering commercial launch vehicles, human transportation, space station logistics, and other space transportation requirements over the next 40 years. Three options are being considered for human transportation: continued use of the Space Shuttle; development of a small personnel carrier...
Topics: NASA Technical Reports Server (NTRS), LAUNCH VEHICLES, NASA PROGRAMS, SINGLE STAGE TO ORBIT...
There are various elements such as radio frequency interference (RFI) which may induce errors in data being transmitted via a satellite communication link. When a transmission is affected by interference or other error-causing elements, the transmitted data becomes indecipherable. It becomes necessary to implement techniques to recover from these disturbances. The objective of this research is to develop software which simulates error control circuits and evaluate the performance of these...
Topics: NASA Technical Reports Server (NTRS), BIT ERROR RATE, CODERS, CODING, COMPUTERIZED SIMULATION,...
This work is the continuation of an optical technique development program initiated as part of the 1992 Summer Faculty Fellowship Program. The 1992 work consisted of the formulation and implementation of a technique ivolving the spatial deconvolution of fluorescence data from a uniformly illuminated, seeded densed spray to obtain quantitative measurements of the liquid density profiles. This measurement approach largely overcomes substantial scattering problems associated with other optical...
Topics: NASA Technical Reports Server (NTRS), FLOW DISTRIBUTION, FUEL INJECTION, FUEL SPRAYS, HYDROGEN...
NASA Headquarters is placing a high priority on the transfer of NASA and NASA contractor developed technologies and expertise to the private sector and to other federal, state and local government organizations. The ultimate objective of these efforts is positive economic impact, an improved quality of life, and a more competitive U.S. posture in international markets. The Technology Utilization Office (TUO) currently serves seven states with its technology transfer efforts. Since 1989, the TUO...
Topics: NASA Technical Reports Server (NTRS), DATA BASES, DESIGN ANALYSIS, SYSTEMS ENGINEERING, TECHNOLOGY...
The rolling element bearings (REB's) which support many turbomachinery rotors offer high load capacity, low power requirements, and durability. Two disadvantages of REB's are: (1) rolling or sliding contact within the bearing has life-limiting consequences; and (2) REB's provide essentially no damping. The REB's in the Space Shuttle Main Engine (SSME) turbopumps must sustain high static and dynamic loads, at high speeds, with a cryogenic fluid as lubricant and coolant. The pump end ball...
Topics: NASA Technical Reports Server (NTRS), DAMPING, DURABILITY, DYNAMIC LOADS, FOIL BEARINGS, STATIC...
Dendrites are prevented from shorting a secondary lithium battery by use of a first porous separator, such as porous polypropylene, adjacent to the lithium anode that is unreactive with lithium and a second porous fluoropolymer separator between the cathode and the first separator, such as polytetrafluoroethylene, that is reactive with lithium. As the tip of a lithium dendrite contacts the second separator, an exothermic reaction occurs locally between the lithium dendrite and the fluoropolymer...
Topics: NASA Technical Reports Server (NTRS), ANODES, CATHODES, EXOTHERMIC REACTIONS, LITHIUM,...
An ultrasonic data display system was developed at NASA Lewis Research Center that allows the user to interactively examine digitized waveforms and processed information associated with any specific scan location of an ultrasonic contact scan. This information is displayed on a video display monitor and includes acquired time-domain waveforms, frequency-domain magnitude and phase spectra, and ultrasonic properties (pulse velocity, phase velocity, reflection coefficient, attenuation coefficient,...
Topics: NASA Technical Reports Server (NTRS), DISPLAY DEVICES, IMAGE ANALYSIS, NONDESTRUCTIVE TESTS,...
This report describes the analysis performed and the findings of a study of the software development cost and schedule estimation models used by the Flight Dynamics Division (FDD), Goddard Space Flight Center. The study analyzes typical FDD projects, focusing primarily on those developed since 1982. The study reconfirms the standard SEL effort estimation model that is based on size adjusted for reuse; however, guidelines for the productivity and growth parameters in the baseline effort model...
Topics: NASA Technical Reports Server (NTRS), COST ESTIMATES, MATHEMATICAL MODELS, PROJECT PLANNING,...
Applying equal testing and verification effort to all parts of a software system is not very efficient, especially when resources are limited and scheduling is tight. Therefore, one needs to be able to differentiate low/high fault frequency components so that testing/verification effort can be concentrated where needed. Such a strategy is expected to detect more faults and thus improve the resulting reliability of the overall system. This paper presents the Optimized Set Reduction approach for...
Topics: NASA Technical Reports Server (NTRS), COMPUTER PROGRAMS, IDENTIFYING, MACHINE LEARNING,...
The objective of this study is to investigate the yarn geometry of multiaxial preforms. The importance of multiaxial preforms for structural composites is well recognized by the industry but, to exploit their full potential, engineering design rules must be established. This study is a step in that direction. In this work the preform geometry for knitted and braided preforms was studied by making a range of well designed samples and studying them by photo microscopy. The structural geometry of...
Topics: NASA Technical Reports Server (NTRS), APPLICATIONS PROGRAMS (COMPUTERS), COMPOSITE MATERIALS,...
Our objectives were to use modem geodetic data, especially those derived from space techniques like Very Long Baseline Interferometry (VLBI), Satellite Laser Ranging (SLR), and the Global Positioning System (GPS) to infer crustal deformation in southern California and relate it to plate tectonics and earthquake hazard. To do this, we needed to collect some original data, write computer programs to determine positions of survey markers from geodetic observables, interpret time dependent...
Topics: NASA Technical Reports Server (NTRS), CALIFORNIA, CRUSTAL FRACTURES, DEFORMATION, EARTHQUAKES,...
A new technology was developed in this study which provides a successful numerical simulation of the whole process of flow transition in 3-D boundary layers, including linear growth, secondary instability, breakdown, and transition at relatively low CPU cost. Most other spatial numerical simulations require high CPU cost and blow up at the stage of flow breakdown. A fourth-order finite difference scheme on stretched and staggered grids, a fully implicit time marching technique, a...
Topics: NASA Technical Reports Server (NTRS), BOUNDARY LAYER STABILITY, BOUNDARY LAYER TRANSITION,...
The differentiation matrix for a spline-based wavelet basis is constructed. Given an n-th order spline basis it is proved that the differentiation matrix is accurate of order 2n + 2 when periodic boundary conditions are assumed. This high accuracy, or superconvergence, is lost when the boundary conditions are no longer periodic. Furthermore, it is shown that spline-based bases generate a class of compact finite difference schemes.
Topics: NASA Technical Reports Server (NTRS), FINITE DIFFERENCE THEORY, SPLINES, WAVELET ANALYSIS, BOUNDARY...
As outlined in the continuation proposal 92-ISI-50R (revised) on NASA cooperative agreement NCC 2-539, the investigators are developing software, including a system manager and a job manager, that will manage available resources and that will enable programmers to develop and execute parallel applications in terms of a virtual configuration of processors, hiding the mapping to physical nodes; developing communications routines that support the abstractions implemented; continuing the...
Topics: NASA Technical Reports Server (NTRS), COMPUTER INFORMATION SECURITY, COMPUTER NETWORKS, DISTRIBUTED...
Chenopodium quinoa is being considered as a new crop for the Controlled Ecological Life Support System (CELSS) because of its high protein values (12 - 18%) and unique amino acid composition. Lysine, and essential amino acid that is deficient in many grain crops, is found in quinoa approaching Food and Agriculture Organization of the United Nations (FAO) standards set for humans. This 'new' crop, rich in protein and with desirable proportions of important amino acids, may provide greater...
Topics: NASA Technical Reports Server (NTRS), CLOSED ECOLOGICAL SYSTEMS, CONTROLLED ATMOSPHERES, CROP...
New turbulence modeling options recently implemented for the 3-D version of Proteus, a Reynolds-averaged compressible Navier-Stokes code, are described. The implemented turbulence models include: the Baldwin-Lomax algebraic model, the Baldwin-Barth one-equation model, the Chien k-epsilon model, and the Launder-Sharma k-epsilon model. Features of this turbulence modeling package include: well documented and easy to use turbulence modeling options, uniform integration of turbulence models from...
Topics: NASA Technical Reports Server (NTRS), BOUNDARY LAYER STABILITY, COMPRESSIBLE FLOW, NAVIER-STOKES...
We develop a new numerical approach to study the spatially evolving instability of the streamwise dominant flow in the presence of roughness elements. The difficulty in handling the flow over the boundary surface with general geometry is removed by using a new conservative form of the governing equations and an analytical mapping. The numerical scheme uses second-order backward Euler in time, fourth-order central differences in all three spatial directions, and boundary-fitted staggered grids....
Topics: NASA Technical Reports Server (NTRS), BOUNDARY LAYER TRANSITION, FOURIER ANALYSIS, GRID GENERATION...
Relaxation-based multigrid solvers for the steady incompressible Navier-Stokes equations are examined to determine their computational speed and robustness. Four relaxation methods with a common discretization have been used as smoothers in a single tailored multigrid procedure. The equations are discretized on a staggered grid with first order upwind used for convection in the relaxation process on all grids and defect correction to second order central on the fine grid introduced once per...
Topics: NASA Technical Reports Server (NTRS), COMPUTATIONAL GRIDS, INCOMPRESSIBLE FLOW, MULTIGRID METHODS,...
Stanford Telecom developed the Three-Dimensional Event-Driven Graphics Environment (3D-EDGE) for NASA GSFC's (GSFC) Communications Link Analysis and Simulation System (CLASS). 3D-EDGE consists of a library of object-oriented subroutines which allow engineers with little or no computer graphics experience to programmatically manipulate, render, animate, and access complex three-dimensional objects.
Topics: NASA Technical Reports Server (NTRS), COMMUNICATION NETWORKS, COMPUTER GRAPHICS, COMPUTERIZED...
The convergence rate of standard multigrid algorithms degenerates on problems with stretched grids or anisotropic operators. The usual cure for this is the use of line or plane relaxation. However, multigrid algorithms based on line and plane relaxation have limited and awkward parallelism and are quite difficult to map effectively to highly parallel architectures. Newer multigrid algorithms that overcome anisotropy through the use of multiple coarse grids rather than relaxation are better...
Topics: NASA Technical Reports Server (NTRS), ALGORITHMS, ANISOTROPY, MULTIGRID METHODS, PARALLEL...
Network Control Center (NCC) Project metrics are captured during the implementation and testing phases of the NCCDS software development lifecycle. The metrics data collection and reporting function has interfaces with all elements of the NCC project. Close collaboration with all project elements has resulted in the development of a defined and repeatable set of metrics processes. The resulting data are used to plan and monitor release activities on a weekly basis. The use of graphical outputs...
Topics: NASA Technical Reports Server (NTRS), COMMUNICATION NETWORKS, DATA ACQUISITION, NETWORK CONTROL,...
This document contains a mixture of tools and equipment used throughout the space shuttle-based extravehicular activity (EVA) program. Promising items which have reached the prototype stage of development are also included, but should not be considered certified ready for flight. Each item is described with a photo, a written discussion, technical specifications, dimensional drawings, and points of contact for additional information. Numbers on the upper left-hand corner of each photo may be...
Topics: NASA Technical Reports Server (NTRS), EXTRAVEHICULAR ACTIVITY, SPACE MAINTENANCE, SPACE TOOLS,...
An investigation was conducted at wind-off conditions in the static-test facility of the Langley 16-Foot Transonic Tunnel to determine the internal performance characteristics of a single expansion-ramp nozzle with thrust-vectoring capability to 105 degrees. Thrust vectoring was accomplished by the downward rotation of an upper flap with adaptive capability for internal contouring and a corresponding rotation of a center-pivoted lower flap. The static internal performance of configurations with...
Topics: NASA Technical Reports Server (NTRS), NOZZLE EFFICIENCY, NOZZLE GEOMETRY, NOZZLE THRUST...
Current object-oriented analysis and design methodologies fall short in their use of mechanisms for identifying threads of control for the system being developed. The scenarios which typically describe a system are more global than looking at the individual objects and representing their behavior. Unlike conventional methodologies that use data flow and process-dependency diagrams, object-oriented methodologies do not provide a model for representing these global threads end-to-end. Tracing...
Topics: NASA Technical Reports Server (NTRS), DATA FLOW ANALYSIS, OBJECT-ORIENTED PROGRAMMING, SOFTWARE...
This paper uses production models to identify and quantify efficient allocation of resources and key drivers of software productivity for project data in the NASA-SEL database. While analysis allows identification of efficient projects, many of the metrics that could have provided a more detailed analysis are not at a level of measurement to allow production model analysis. Production models must be used with proper parameterization to be successful. This may mean a new look at which metrics...
Topics: NASA Technical Reports Server (NTRS), COMPUTER PROGRAMMING, PARAMETERIZATION, PRODUCTION...
