14
Topics: Spectrograph, Stars -- Motion in line of sight
14
Topics: Double stars, Stars -- Motion in line of sight
139
139
Jan 29, 2006
01/06
by
Line Of Sight
movies
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"The Day After" by Line Of Sight - Filmed and edited by Raymond Buckley (Arcane Pictures)
Topics: The Day After, Line Of Sight, Arcane Pictures
Source: www.myspace.com/lineofsight1
Line-of-sight (LOS) calculation for the Janus combat simulation model is critical to the processes being simulated and impacts the run speed (ratio of game time to real time), since it may be the single most computationally expensive algorithm in simulation. TIlls thesis presents design and implementation of a transputer network with the purpose ofproYiding an efficient LOS calculation in a distributed memory and computing environment. The approach taken was to use a processor fanning method to...
Topic: Janus, Transputer, Pegasus Database, Parallellism, Line-of-Sight
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197
Feb 9, 2006
02/06
by
Video: Arcane Pictures / Music: Line Of Sight
movies
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For more information on "Line Of Sight", and to be able to se it with sound (upload problems), come to ArcanePicturesOnline.com.
Topics: Line of Sight, The Hanger, Benefit Concert, Arcane Pictures
Source: MySpace.com/LineOfSight1
The objective of this research is to understand the abilities and limitations of communication in a radio frequencies (RF)-denied environment, especially with regard to the network stack. The next generation of warfare with another state actor will require non-traditional communication and extra security methods. RF and wired communications can be destroyed, jammed or not suitable. Free-space optics (FSO) provides the potential for high-speed communication between networks in an RF-denied...
Topics: line of sight communication, QR code, RF-denied environment
High-resolution combat simulations that model urban combat currently use computationally expensive algorithms to represent urban target acquisition at the entity level. While this may be suitable for small-scale urban combat scenarios, simulation run time can become unacceptably long for larger scenarios. Consequently, there is a need for models that can lend insight into target acquisition in urban terrain for largescale scenarios in an acceptable length of time. This research develops urban...
Topics: Urban warfare, Markov processes, Probability of line of sight, Line of sight, Urban target...
169
169
Jan 6, 2014
01/14
by
C. SWARNALATHA1 & T. S. PRASANNA2
texts
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Establishing a clear line of sight and building an employer brand around it from inside the organization while leveraging leadership, communication, employee development and corporate & social responsibility may not be something entirely new to the world of strategic HRM, but it does appear to be a worthwhile investment, especially with regard to employee engagement. This paper examines engagement as it relates to employment these subjects and offers suggestions for HR practitioners.
Topics: Line of Sight, Employment Brand, Leadership, Communication, Employee Development, Corporate Social...
1,892
1.9K
Jun 12, 2011
06/11
by
NON
texts
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Volume 3 of the 2003 Air Transport Reserch Society (ATRS) World Conference includes papers on topics relevant to airline operations worldwide. Specific topics include: European Union and civil aviation regimens;simulating decision making in airline operations, passenger points of view on convenient airports; route monopolies and nonlinear pricing; cooperation among airports in Europe; fleet modernizaiton in Brazil;the effects of deregulation on the growth of air transportation in Europe and the...
Topics: ATOMIC PHYSICS, X RAYS, NUCLEAR PHYSICS, SEYFERT GALAXIES, PHOTOABSORPTION, LINE OF SIGHT
167
167
May 23, 2011
05/11
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Moore, David; Cohen, Ross D
texts
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We present model line profiles of [O II] lambda3727, [Ne III] lambda3869, [O I] lambda5007, [Fe VII] lambda6087, [Fe X] lambda6374, [O I] lambda6300, H(alpha) lambda6563, and [S 2] lambda6731. The profiles presented here illustrate explicitly the pronounced effects that collisional de-excitation, and that spatial variations in both the ionization parameter and cloud column density, have on Narrow-Line Region (NLR) model profiles. The above effects were included only qualitatively in a previous...
Topics: MERIDIONAL FLOW, SUN, SOLAR OSCILLATIONS, SOLAR ACTIVITY, LINE OF SIGHT, FLOW VELOCITY,...
214
214
May 23, 2011
05/11
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Reddy, D. R.; Lafe, O.; Cheng, A. H-D
texts
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Using global interpolation functions (GIF's), boundary element solutions are obtained for two- and three-dimensional viscous flows. The solution is obtained in the form of a boundary integral plus a series of global basis functions. The unknown coefficients of the GIF's are determined to ensure the satisfaction of the governing equations at selected collocation points. The values of the coefficients involved in the boundary integral equations are determined by enforcing the boundary conditions....
Topics: KALMAN FILTERS, MULTISENSOR FUSION, GRAVIMETRY, ATTITUDE (INCLINATION), DYNAMIC RESPONSE, LINE OF...
This thesis compares two types of command guidance to be used by a point defense system: Proportional Navigation and Command to Line Of Sight (CLOS). The system block diagram was first defined. The necessary transfer functions were derived. Two forward time models were evaluated, one for each guidance method, using state variable analysis. Two three dimensional scenarios were defined and their results used to compare the two methods. Parameters considered in the comparison were miss distance...
Topics: Proportional navigation command guidance, Command to line of sight guidance, Missile guidance,...
166
166
May 27, 2011
05/11
by
Thompson, Anne M.; Hudson, Robert D
texts
eye 166
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The well-known wave-one pattern seen in tropical total ozone [Shiotani, 1992; Ziemke et al., 1996, 1998] has been used to develop a modified-residual (MR) method for retrieving time-averaged stratospheric ozone and tropospheric ozone column amount from TOMS (Total Ozone Mapping Spectrometer) over the 14 complete calendar years of Nimbus 7 observations (1979-1992) and from TOMS on the Earth-Probe (1996-present) and ADEOS platforms (1996- 1997). Nine- to sixteen-day averaged tropical tropospheric...
Topics: COMMUNICATION, PREDICTIONS, HYPOTHESES, DATA ACQUISITION, SMOKE, MOUNTAINS, LINE OF SIGHT, ISRAEL,...
242
242
May 24, 2011
05/11
by
Goulb, Leo
texts
eye 242
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SAO is involved in a study to determine the feasibility of building an orbiting telescope capable of resolving 7 km structure on the Sun. In order to achieve the required imaging the telescope must have a resolution 0.01 arcsec. This fact challenges the state of the art of orbiting telescopes in several areas: Mirror Figuring; Optical Metrology; Optical Mounting; Mirror Figure Control; System Alignment; Optical Stability; Observatory Pointing; and Image Stability. The telescope design concept...
Topics: ATOMIC PHYSICS, SPECTROGRAPHS, HIGH RESOLUTION, LINE OF SIGHT, HUBBLE SPACE TELESCOPE, INTERSTELLAR...
1,163
1.2K
Jun 11, 2011
06/11
by
NON
texts
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This custom bibliography from the NASA Scientific and Technical Information Program lists a sampling of records found in the NASA Aeronautics and Space Database. The scope of this topic includes cooling technologies for precision astronomical sensors and advanced spacecraft, as well as propellant storage and transfer in space. This area of focus is one of the enabling technologies as defined by NASA's Report of the President's Commission on Implementation of United States Space Exploration...
Topics: WATER VAPOR, SOFIA (AIRBORNE OBSERVATORY), RADIOMETERS, LINE OF SIGHT, BOEING 747 AIRCRAFT,...
This thesis focuses on potential tactical uses of Quick Response (QR) codes for optical signaling. It examines visual communications methods used effectively by the fleet throughout history, both during peace and wartime operations. Due to the advent of new technology, radio frequency line-of-sight (RF LOS) communications have come to the forefront of current operations, leaving the fleet vulnerable when conducting operations in an emissions controlled (EMCON) environment. In addition, the use...
Topics: Digital Semaphore, Emissions Control (EMCON), QR Code, Radio Frequency line-of-sight (RF LOS),...
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170
Sep 20, 2010
09/10
by
NON
texts
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A split rail gripper for robotic apparatus, including a pair of rails which are driven in mutually opposite directions by a rack and pinion gear mechanism is presented. Each rail includes a set of rack gear teeth which engage respective pinion gears and where the top rail engaging one of the pinion gears is driven by a harmonic gear reduction drive and motor unit coupled to an acme screw. The other pinion gear is driven by the top pinion gear engaging a set of rack gear teeth included in the...
Topics: INTERFEROMETRY, ORBIT CALCULATION, PIONEER VENUS SPACECRAFT, SATELLITE DOPPLER POSITIONING, LINE OF...
This thesis focuses on potential tactical uses of Quick Response (QR) codes for optical signaling. It examines visual communications methods used effectively by the fleet throughout history, both during peace and wartime operations. Due to the advent of new technology, radio frequency line-of-sight (RF LOS) communications have come to the forefront of current operations, leaving the fleet vulnerable when conducting operations in an emissions controlled (EMCON) environment. In addition, the use...
Topics: Digital Semaphore, Emissions Control (EMCON), QR Code, Radio Frequency line-of-sight (RF LOS),...
NASA technology has produced a laser-aided system for surveying land boundaries in difficult terrain. It does the job more accurately than conventional methods, takes only one-third the time normally required, and is considerably less expensive. In surveying to mark property boundaries, the objective is to establish an accurate heading between two "corner" points. This is conventionally accomplished by erecting a "range pole" at one point and sighting it from the other point...
Topics: NASA Technical Reports Server (NTRS), LASER APPLICATIONS, LINE OF SIGHT, SURVEYS, TERRAIN,...
101
101
Jun 2, 2011
06/11
by
Brat, Guillaume; Havelund, Klaus; Park, SeungJoon; Visser, Wille
texts
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Software, particularly systems capable of autonomous operation, is fast becoming a major enabling technology at NASA. Unfortunately, the cost savings of autonomous software systems can easily be offset by the risk of in-flight failure of the software. Although rigorous testing of software before deployment can increase the confidence of its correctness, the tendency of in-flight software to be multi-threaded makes it hard to find subtle errors caused by the unforeseen interaction of...
Topics: INTERSTELLAR MATTER, LINE OF SIGHT, NITRILES, CYANIDES, BIOLOGICAL EVOLUTION, ORGANIC MATERIALS,...
Current attempts to dissect the inner workings of Narrow-Line Seyfert 1 galaxies (NLS1s) rely on the concept that narrow widths of their permitted lines are due to low central black hole masses resulting in high Eddington ratios. Could these narrow lines instead be due to a near pole-on orientation? We analyze spatially resolved spectra of the NLS1 NGC 4051 using the HST STIS G430M grating centered on the bright [O III] emission lines to model the narrow-line region (NLR) outflow and determine...
Topics: DTIC Archive, NAVAL RESEARCH LAB WASHINGTON DC, *GALAXIES, *ORIENTATION(DIRECTION), BLACK HOLES,...
There are two main approaches to managing wargame entity interactions (movement, line of sight, area of effect, etc) freespace and gridded In the freespace approach, the units exist as entities in a continuous volume of (usually) Cartesian 3D space. They move in any direction (based on interaction with "terrain" that occupies the same space) and interact with each other based on references and displacements from their position in that space. In the gridded approach, space is broken up...
Topics: NASA Technical Reports Server (NTRS), CARTESIAN COORDINATES, GAMES, HEXAGONS, LINE OF SIGHT,...
200
200
Jun 9, 2011
06/11
by
Proctor, Fred H
texts
eye 200
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A numerical large-eddy simulation model is under modification and testing for application to aircraft wake vortices. The model, having a meteorological framework, permits the interaction of wake vortices with environments characterized by crosswind shear, stratification, and humidity. As part of the validation process, model results are compared with measured field data from the 1990 Idaho Falls and the 1994-1995 Memphis field experiments. Cases are selected that represent different aircraft...
Topics: EXPERIMENTATION, DATA ACQUISITION, INTEGRATED CIRCUITS, CONTROLLERS, DESIGN OPTIMIZATION, LINE OF...
Journal of Research of the National Bureau of Standards
Topics: phase stability, whf, uhf, microwave radio, weather, phase variation, Sanborn, line-of-sight path,...
Meteor echoes come from random points in the observation volume, and are irregularly spaced in time. This precludes the use of fast fourier transformations (FFT) techniques on the raw data to give the spectrum of waves that are present. One way around this obstacle is to restrict our interest to a particular class of waves, and fit a corresponding model to the raw data. It is assumed that there is no horizontal variation across the observation volume for tides, but in the vertical this is...
Topics: NASA Technical Reports Server (NTRS), EARTH TIDES, FAST FOURIER TRANSFORMATIONS, INTERPOLATION,...
412
412
May 6, 2010
05/10
by
Wood, William A.; Kleb, William L.; Tang, chun Y.; Palmer, Grant E.; Hyatt, Andrew J.; Wise, Adam J.; McCloud, Peter L
texts
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Surface temperature measurements from the STS-119 boundary-layer transition experiment on the space shuttle orbiter Discovery provide a rare opportunity to assess turbulent CFD models at hypersonic flight conditions. This flight data was acquired by on-board thermocouples and by infrared images taken off-board by the Hypersonic Thermodynamic Infrared Measurements (HYTHIRM) team, and is suitable for hypersonic CFD turbulence assessment between Mach 6 and 14. The primary assessment is for the...
Topics: GAMMA RAY BURSTS, MILKY WAY GALAXY, RED SHIFT, AFTERGLOWS, DUST, LIGHT CURVE, LINE OF SIGHT,...
344
344
May 27, 2011
05/11
by
Carney, Terrance M
texts
eye 344
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This study includes a consideration of the design philosophy for an automatic terminal guidance system, a derivation of guidance equations required, and an outline of the general type of instrumentation necessary to provide the essential information. A control system for a sample vehicle is analyzed. A representative case, rendezvous with a satellite in circular orbit at 400 nautical miles, was examined. Terminal-stage nominal burning times of 200 and 400 seconds were used. For the 200-second...
Topics: FLIGHT PATHS, SPACE RENDEZVOUS, PILOT PERFORMANCE, OPTICAL EQUIPMENT, ANGULAR VELOCITY, LINE OF...
This research is concerned with dynamically determining appropriate flight patterns for a set of autonomous UAVs in an urban environment, with multiple mission goals. The UAVs are tasked with searching the urban region for targets of interest, and tracking those targets that have been detected. We assume that there are limited communication capabilities between the UAVs, and that there exist possible line of sight constraints between the UAVs and the targets. Each UAV (i) operates its own...
Topics: DTIC Archive, RAYTHEON CO ORLANDO FL, *CONTROL, *HETEROGENEITY, *RESOURCES, DECENTRALIZATION, LINE...
With the launch of the European Space Agency's Aeolus Mission in 2013, direct spaceborne measurements of vertical wind profiles are imminent via Doppler wind lidar technology. Part of the preparedness for such missions is the development of the proper data assimilation methodology for handling such observations. Since no heritage measurements exist in space, the Joint Observing System Simulation Experiment (Joint OSSE) framework has been utilized to generate a realistic proxy dataset as a...
Topics: NASA Technical Reports Server (NTRS), DOPPLER RADAR, SIMULATION, SPACE MISSIONS, WIND PROFILES,...
To develop an environmentally benign advanced nanocrystalline based coating technology that: (1) Is compatible with conventional electroplating infrastructure; (2) Meets or exceed the performance of hard chrome; (3) Costs similar to or less than existing hard chrome processes; and (4) Will be applied to non-line-of-sight surfaces.
Topics: DTIC Archive, INTEGRAN TECHNOLOGIES USA INC PITTSBURGH PA, *COATINGS, *ELECTRODEPOSITION, CHROMIUM,...
252
252
May 28, 2011
05/11
by
Bowen, Brent D.; Headley, Dean E
texts
eye 252
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The Airline Quality Rating (AQR) was developed and first announced in early 1991 as an objective method of comparing airline performance on combined multiple criteria. This current report, Airline Quality Rating 1999, reflects an updated approach to calculating monthly Airline Quality Rating scores for 1998. AQR scores for the calendar year 1998 are based on 15 elements that focus on airline performance areas important to air travel consumers. The Airline Quality Rating is a summary of...
Topics: FLAMES, GROUND STATE, KINETICS, LASER INDUCED FLUORESCENCE, HYDROCARBONS, SPATIAL DISTRIBUTION,...
In multi-vehicle mine hunting operations, it will be necessary at times for one vehicle to loiter at some point while gathering communications of data from other vehicles. The loitering behaviors of the ARIES Autonomous Underwater Vehicle have never been completely defined. The track that the vehicle chooses to maintain station while circling around one specific point for an extended period of time may be sometimes random and unpredictable, unless defined in terms of specific tracks....
Topics: Autonomous robots, Remote submersibles, Autonomous Underwater Vehicles, Robotics, Loitering...
The spatial and temporal characteristics of human visual localization are studied using psychophysical techniques. The primary tasks studied are frequency discrimination and distance judgments in the plane perpendicular o the observer's line of sight. It is found that these tasks cannot be performed directly on the basis of simple transformations of the retinal image, but depend on stimulus context and on judgment of stimulus depth. Experiments are designed to isolate the process underlying...
Topics: DTIC Archive, Burbeck, Christina A, SRI INTERNATIONAL MENLO PARK CA SENSORY SCIENCES RESEARCH LAB,...
In order to provide for the safe integration of unmanned aircraft systems (UAS) into the National Airspace System (NAS), the control and non-payload communications (CNPC) link must be highly reliable. A specific requirement is that it must operate using aviation safety radiofrequency spectrum. Two types of links are required - line-of-sight (LOS) using terrestrial-based communications and beyond-line- of-sight (BLOS) using satellite communications. The 2012 World Radiocommunication Conference...
Topics: NASA Technical Reports Server (NTRS), UNMANNED AIRCRAFT SYSTEMS, NATIONAL AIRSPACE SYSTEM,...
Topics: DTIC Archive, AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH, *CADMIUM, *COATINGS, COBALT, LINE OF...
In the fifth quarter of the work effort, we focused on (a) conducting experiments on real-world data sets using the developed algorithms, (b) design of the Multiscale Singular Value Decomposition (SVD) algorithm, (c) preliminary design of the Multiscale Heat-Kernel Coordinates algorithm and (d) fine tuning and bug fixes for the randomized SVD and ANN algorithms. This report documents the line-of-sight experiments using radio-frequency (RF) data. The project is currently on track in the upcoming...
Topics: DTIC Archive, TELCORDIA TECHNOLOGIES INC PISCATAWAY NJ, *ALGORITHMS, *RADIO SIGNALS, EXPERIMENTAL...
In order to provide for the safe integration of unmanned aircraft systems (UAS) into the National Airspace System (NAS), the control and non-payload communications (CNPC) link must be highly reliable. A specific requirement is that it must operate using aviation safety radiofrequency spectrum. Two types of links are required - line-of-sight (LOS) using terrestrial-based communications and beyond-line-of-sight (BLOS) using satellite communications. The 2012 World Radiocommunication Conference...
Topics: NASA Technical Reports Server (NTRS), PILOTLESS AIRCRAFT, UNMANNED AIRCRAFT SYSTEMS, NATIONAL...
313
313
May 30, 2011
05/11
by
Micol, John R
texts
eye 313
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Description, capabilities, initiatives, and utilization of the NASA Langley Research Center's Unitary Plan Wind Tunnel are presented. A brief overview of the facility's operational capabilities and testing techniques is provided. A recent Construction of Facilities (CoF) project to improve facility productivity and efficiency through facility automation has been completed and is discussed. Several new and maturing thrusts are underway that include systematic efforts to provide credible...
Topics: AEROSPACE ENVIRONMENTS, GALACTIC RADIATION, CONTAMINATION, CONTAMINANTS, ENVIRONMENT EFFECTS, LINE...
An algorithm has been developed to initiate tracks of a ballistic missile in initial exoatmospheric phase, using line of sight measurements from one or more moving platforms.
Topics: DTIC Archive, Bar-Shalom, Y., CONNECTICUT UNIV STORRS, *GUIDED MISSILES, *MULTISENSORS, ALGORITHMS,...
The U.S. Navy has been tasked to upgrade link M0672, Mormond Hill-Latheron, UK for digital operations. Technical guidance was requested from DCEC to analyze link performance expected of the digital configuration and to assess the potential of using DIDICOM units in conjunction with quad diversity. Keywords included: Link performance, Path profile, Digital upgrade, Fading; Ducting, and Diversity mode.
Topics: DTIC Archive, Sorovacu,Nicholas J, DEFENSE COMMUNICATIONS ENGINEERING CENTER RESTON VA, *DIGITAL...
328
328
Jun 9, 2011
06/11
by
Simon, Donald L.; Gang, Sanjay; Hunter, Gary W.; Guo, Ten-Huei; Semega, Kenneth J
texts
eye 328
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NASA and the U.S. Department of Defense are conducting programs which support the future vision of ''intelligent'' aircraft engines for enhancing the affordability, performance, operability, safety, and reliability of aircraft propulsion systems. Intelligent engines will have advanced control and health management capabilities enabling these engines to be self-diagnostic, self-prognostic, and adaptive to optimize performance based upon the current condition of the engine or the current mission...
Topics: NUMERICAL ANALYSIS, DESIGN ANALYSIS, FUZZY SYSTEMS, CONTROLLERS, LOGIC DESIGN, TUNING, SPACECRAFT...
The helmet-mounted display (HMD) presents flight, sensor, and weapon information in the pilot's line of sight. The HMD was developed to allow the pilot to retain aircraft and weapon information and to view sensor images while looking off boresight.
Topics: NASA Technical Reports Server (NTRS), HELMET MOUNTED DISPLAYS, LINE OF SIGHT, DISPLAY DEVICES,...
For more than a decade, the U.S. government has been developing laser-based sensors for detecting, locating, and classifying aerosols in the atmosphere at safe standoff ranges. The motivation for this work is the need to discriminate aerosols of biological origin from interferent materials such as smoke and dust using the backscatter from multiple wavelengths in the long wave infrared (LWIR) spectral region. Through previous work, algorithms have been developed for estimating the aerosol...
Topics: DTIC Archive, CALIFORNIA UNIV LOS ANGELES, *AEROSOLS, *ALGORITHMS, BACKSCATTERING, DETECTORS,...
294
294
May 27, 2011
05/11
by
Swanson, Andrew G
texts
eye 294
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A five-stage solid-fuel sounding-rocket system which can boost a payload of 25 pounds to an altitude of 525 nautical miles and that of 100 pounds to 300 nautical miles is described. Data obtained from a typical flight test of the system are discussed.
Topics: RADAR HOMING MISSILES, MANEUVERABILITY, LINE OF SIGHT, CONTROL SYSTEMS DESIGN, DIFFRACTION,...
The Coronagraph Performance Error Budget (CPEB) tool automates many of the key steps required to evaluate the scattered starlight contrast in the dark hole of a space-based coronagraph. The tool uses a Code V prescription of the optical train, and uses MATLAB programs to call ray-trace code that generates linear beam-walk and aberration sensitivity matrices for motions of the optical elements and line-of-sight pointing, with and without controlled fine-steering mirrors (FSMs). The sensitivity...
Topics: NASA Technical Reports Server (NTRS), CORONAGRAPHS, TELESCOPES, ERRORS, LINE OF SIGHT, MIRRORS,...
The Airborne Aero-Optics Laboratory \201AAOL\202 was designed to measure the effects of turbulent flow on the wavefront of a laser projected from an airplane in flight. An integrated line-of-sight model that predicts closed-loop jitter of the AAOL system is presented. The influence of model uncertainty with model tuning based on available experimental measurements was examined for one flight condition.
Topics: DTIC Archive, BOEING CO CHICAGO IL, *LINE OF SIGHT, *OPTICAL EQUIPMENT, AIRBORNE, CLOSED LOOP...
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236
May 23, 2011
05/11
by
Kavaya, Michael J.; Spiers, Gary D.; Lobl, Elena S.; Rothermel, Jeff; Keller, Vernon W
texts
eye 236
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Innovative designs of a space-based laser remote sensing 'wind machine' are presented. These designs seek compatibility with the traditionally conflicting constraints of high scientific value and low total mission cost. Mission cost is reduced by moving to smaller, lighter, more off-the-shelf instrument designs which can be accommodated on smaller launch vehicles.
Topics: MIE SCATTERING, INFRARED RADIATION, PROTOSTARS, ABSORPTION SPECTRA, CARBONYL COMPOUNDS, INFRARED...
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1.5K
May 28, 2011
05/11
by
Berner, Stepha
texts
eye 1,511
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It may be desired to apply Digital Signal Processing (DSP) to high bandwidth signals with a sampling rate too high for being handled by any commercially available processor. One approach to solve this problem is to divide the spectrum of the signal into subbands by an analysis filter bank, then process the subbands in parallel, and finally, recombine the processed subband signals by a synthesis filter bank. The key point is the fact, that the sampling rate in the subbands can be reduced by...
Topics: PLANETARY SYSTEMS, ASTEROIDS, STELLAR MASS, PROTOPLANETS, A STARS, B STARS, HERBIG-HARO OBJECTS,...
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439
Jun 1, 2011
06/11
by
Rice, Chad; Buehrle, Ralph D
texts
eye 439
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Vibration tests were performed to develop and validate the forced limited vibration testing capability at the NASA Langley Research Center. The force limited vibration test technique has been utilized at the Jet Propulsion Laboratory and other NASA centers to provide more realistic vibration test environments for aerospace flight hardware. In standard random vibration tests, the payload is mounted to a rigid fixture and the interface acceleration is controlled to a specified level based on a...
Topics: FLUID FLOW, LINE OF SIGHT, TWO PHASE FLOW, VELOCITY MEASUREMENT, PLANAR STRUCTURES, ILLUMINATING,...
Doppler velocity data obtained with the Global Oscillation Network Group (GONG) instruments in Tucson from 1992 August through 1995 April were analyzed to determine the structure and evolution of the Sun's meridional flow. Individual measurements of the flow were derived from line-of-sight velocity images averaged over 17 minutes to remove the p-mode oscillation signal. Typical flow velocities are poleward at approximately 20 m/s, but the results suggest that episodes may occur with much...
Topics: NASA Technical Reports Server (NTRS), MERIDIONAL FLOW, SUN, SOLAR OSCILLATIONS, SOLAR ACTIVITY,...
