silkski/ENERAD huggingface dataset:
The DC electrical behavior of n - type 4H - SiC resistors used for realizing 500 degrees Celsius durable integrated circuits ( ICs ) is studied as a function of substrate bias and temperature . Improved fidelity electrical simulation is described using SPICE NMOS model to simulate resistor substrate body bias effect that is absent from the SPICE semiconductor resistor model .
Fiber Bragg - gratings are embedded in carbon - epoxy laminates as well as bonded on the surface of cylindrical structures fabricated out of such composites . Structural properties of such composites is investigated . The measurements include stress - strain relation in laminates and Poisson 's ratio in several specimens with varying orientation of the optical fiber Bragg - sensor with respect to the carbon fiber in an epoxy matrix . Additionally , Bragg gratings are bonded on the surface of cylinders fabricated out of carbon - epoxy composites and longitudinal and hoop strain on the surface is measured .
We present visible spectroscopy measurements using the PerkinElmer Lambda 950 grating monochromator in support of two projects at NASA Goddard Space Flight Center . The first and primary project to be discussed is the Wide Field Planetary Camera 2 as an upgrade to the Hubble Space Telescope . Numerous optical filters were measured in the visible and near - infrared regions to experimentally vet the theoretical prediction upon which the filters were engineered . The second topic of our presentation will cover the measurement of SNAP prototype filters from three venders ( ASAHI , BARR and JDSU ) with applications towards NASAs the Joint Dark Energy Mission ( JDEM ) .
Our goal is to develop a method for the automated attachment of large numbers of absorber tiles to large format detector arrays . This development includes the fabrication of high quality , closely spaced HgTe absorber tiles that are properly positioned for pick - and - place by our FC150 flip chip bonder . The FC150 also transfers the appropriate minute amount of epoxy to the detectors for permanent attachment of the absorbers . The success of this development will replace an arduous , risky and highly manual task with a reliable , high - precision automated process .
Homoepitaxial CVD growth of thin lateral cantilevers emanating from the edges of mesa patterns dry - etched into on - axis commercial 4H - SiC substrates prior to growth is reported . Cantilevers on the order of a micrometer thick extending tens of micrometers from the edge of a mesa have been grown . The termination of vertically propagating screw dislocations , including a micropipe , that are overgrown by the cantilevers has been demonstrated , in large part because the crystal structure of the cantilevers is established laterally from the mesa sidewalls . This technique could help reduce performance - degrading dislocations in SiC electrical devices .
A liquid oxygen turbopump has been designed at Marshall Space Flight Center as part of the in - house , Advanced Manufacturing Demonstrator Engine ( AMDE ) project . Additive manufacturing , specifically direct metal laser sintering ( DMLS ) of Inconel 718 , is used for 77 % of the parts by mass . These parts include the impeller , turbine components , and housings . This paper discusses the impacts of the DMLS fabrication technique on the design of the turbopump and lessons learned during DMLS hardware fabrication and material testing .
Airsickness is experienced by about 50 % of military aviators some time in their career . Aviators who suffer from recurrent episodes of airsickness are typically referred to the Naval Aerospace Medical Institute ( NAMI ) at Pensacola where they undergo extensive evaluation and 8 weeks of training in the Self - Paced Airsickness Desensitization ( SPAD ) program . Researchers at NASA Ames have developed an alternative mitigation training program , Autogenic Feedback Training Exercise ( AFTE ) that has demonstrated an 80 % success rate for improving motion sickness tolerance .
HST / STIS spectral monitoring of Eta Carinae and its ejecta reveals the presence of a relatively small bipolar structure inside the central regions of the familiar Homunculus lobes . Astrometric analysis shows that the Little Homunculus was most likely ejected during the 1890 event . Here we employ a simple plasma analysis on the ejecta : ( 1 ) identify the forbidden [ Fe II ] lines , and ( 2 ) use them with a Boltzmann distribution to estimate a locus in " gas temperature " -versus- " Reddening " parameter space . Our preliminary result shows that gas temperature of the Little Homunculus may be around 5000 K with reddening E(B - V ) approx . = 0.5 of a standard interstellar reddening is valid .
We are in the third year of a five - year effort to map the geology of Mars using mainly Mars Global Surveyor , Mars Express , and Mars Odyssey imaging and altimetry datasets . Previously , we have reported on details of project management , mapping datasets ( local and regional ) , initial and anticipated mapping approaches , and tactics of map unit delineation and description [ 1 - 2 ] . For example , we have seen how the multiple types and huge quantity of image data as well as more accurate and detailed altimetry data now available allow for broader and deeper geologic perspectives , based largely on improved landform perception , characterization , and analysis . Here , we describe mapping and unit delineation results thus far , a new unit identified in the northern plains , and remaining steps to complete the map .
Based on an analysis of aviation decision - makers ' time - related weather information needs , an abstraction of the aviation weather decision task was developed , that involves 4 - D intersection testing between aircraft trajectory hypertubes and hazardous weather hypervolumes . The framework builds on the hypothesis that hazardous meteorological fields can be simplified using discrete boundaries of surrogate threat attributes . The abstractions developed in the framework may be useful in studying how to improve the performance of weather forecasts from the trajectory - centric perspective , as well as for developing useful visualization techniques of weather information .
The results of Rosat observations of superbubbles in the Large Magellanic Cloud provided X - ray spectra for bright objects and data on upper limits of faint objects . The X - ray emission from superbubbles can be used to determine the physical condition of the superbubble interior , place constraints on the ambient interstellar medium , and diagnose the existence of supernova remnant shocks .
A luminous visual target in a dark hypergravity ( Gz greater than 1 ) environment appears to be elevated above its true physical position . This " elevator illusion " has been attributed to changes in oculomotor control caused by increased stimulation of the otolith organs . Data relating the magnitude of the illusion to the magnitude of the changes in oculomotor control have been lacking . The present study provides such data .
The development of lab - on - a - chip devices for microscale biochemical assays has led to the need for microscale concentration measurements of specific analyses . While fluorescence methods are the current choice , this method requires developing fluorophore - tagged conjugates for each analyte of interest . In addition , fluorescent imaging is also a volume - based method , and can be limiting as smaller detection regions are required .
The next generation Earth observing satellites will face challenges in supporting high rate space communications from the increasingly sophisticated instruments . Emerging applications will need space - to - ground links with data rates forecasted to be in the 1 - 20 Gbps range . To meet these challenges , NASA is designing and integrating a 26 GHz Polar Subnet to support space communication needs in 2020 and beyond . This paper describes the current effort of the Space Communications and Navigation Program 's Near Earth Network ( NEN ) , managed out of Goddard Space Flight Facility ( GSFC ) , to deploy a 26 GHz Polar Subnet including the implementation , topology , capabilities , architecture design , operations and key design trades .
The NASA Conjunction Assessment Risk Analysis team has implemented new software to estimate the probability of collision ( P ( sub c ) ) for Earth - orbiting satellites . The algorithm employs a brute force Monte Carlo ( BFMC ) method which differs from most other methods because it uses orbital states and covariances propagated from their orbit determination epoch times using the full set of Astrodynamics Support Workstation higher order theory models , including the High Accuracy Satellite Drag Model . This paper de - scribes the BFMC algorithm , presents comparisons of BFMC P ( sub c ) estimates to those calculated using other methods , and discusses the implications for conjunction risk assessment .
AUTOFILTER is a tool for automatically deriving Kalman filter code from high - level declarative specifications of state estimation problems . It can generate code with a range of algorithmic characteristics and for several target platforms . The tool has been designed with reliability of the generated code in mind and is able to automatically certify that the code it generates is free from various error classes . Since documentation is an important part of software assurance , AUTOFILTER can also automatically generate various human - readable documents , containing both design and safety related information . We discuss how these features address software assurance standards such as DO-178B.
Planetary Protection places requirements on the maximum number of viable bacterial spores that may be delivered by a spacecraft to another solar system body .   Therefore , for such space   missions , the spores that may be found in hydrazine are of concern .   A proposed change in processing procedures that eliminated a 0.2 um filtration step propmpted this study to ensure   microbial contamination issue existed , especially since no information was found in the literature to substantiate bacterial spore inactivation by hydrazine .
Poster presentation will outline on - going efforts at NASA , MSFC to employ various Evolvable Hardware experimental platforms in the evolution of digital and analog circuitry for application to automatic control . Included will be information concerning the application of commercially available hardware and software along with the use of the JPL developed FPTA2 integrated circuit and supporting JPL developed software . Results to date will be presented .
Although massive stars play a critical role in the production of turbulent energy in the ISM , in the formation and destruction of molecular clouds , and ultimately in the dynamical and   chemodynamical evolution of galaxies , our understanding of the sequence of events which leads to their formation is still rather limited .
The Aguas Zarcas meteorite is a new CM2 chondrite which fell on 23 April 2019 ( local time ) in Costa Rica . Aguas Zarcas is brecciated and contains several different lithologies , e.g. , metal - rich lithology and CI - like lithology . This fresh CM2 chondrite gives us good op - portunities for analyses of organic matter ( OM ) without terrestrial contamination and weathering , particularly some stones which were collected before rain fell over the fall site . We also aim to characterize local hetero - geneities and associations of organic and mineral phases using state - of - the - art microscopic techniques to con - strain the origin and evolutionally processes of OM during pre- and post - accretion .
This paper describes the orbit determination process , results and filter strategies used by the Mars Science Laboratory Navigation Team during cruise from Earth to Mars . The new atmospheric entry guidance system resulted in an orbit determination paradigm shift during final approach when compared to previous Mars lander missions . The evolving orbit determination filter strategies during cruise are presented . Furthermore , results of calibration activities of dynamical models are presented . The atmospheric entry interface trajectory knowledge was significantly better than the original requirements , which enabled the very precise landing in Gale Crater .
The Multi - angle Imaging SpectroRadiometer ( MISR ) instrument has been collecting global Earth data from NASA 's Terra satellite since February 2000 . With its nine along - track view angles , four visible / near - infrared spectral bands , intrinsic spatial resolution of 275 m , and stable radiometric and geometric calibration , no instrument that combines MISR 's attributes has previously flown in space . The more than 10 - year ( and counting ) MISR data record provides unprecedented opportunities for characterizing long - term trends in aerosol , cloud , and surface properties , and includes 3 - D textural information conventionally thought to be accessible only to active sensors .
Measurements of the complex . dielectric constant of seawater at 30.00 psu , 35.00 psu and 38.27 psu over the temperature range from 5 C to 3 5 at 1.413 GHz are given and compared with the Klein - Swift results . A resonant cavity technique is used . The calibration constant used in the cavity perturbation formulas is determined experimentally using methanol and ethanediol ( ethylene glycol ) as reference liquids . Analysis of the data shows that the measurements are accurate to better than 1.0 % in almost all cases studied .
In this study optical modulation response and photoluminescence spectroscopy were used to study mid - wave Ga - free InAs / InAsSb superlattices . The minority carrier lifetimes in the different samples varied from 480 ns to 4700 ns , partly due to different background doping concentrations . It was shown that the photoluminescence intensity can be used as a fast non - destructive tool to predict the material quality . It was also demonstrated that it is crucial to use a low excitation power in the photoluminescence measurements in order to get a good correlation between the photoluminescence intensity and the minority carrier lifetime .
As Unmanned Aircraft Systems ( UAS ) make their way to mainstream aviation operations within the National Airspace System ( NAS ) , research efforts are underway to develop a safe and effective environment for their integration into the NAS . Detect and Avoid ( DAA ) systems are required to account for the lack of " eyes in the sky " due to having no human on - board the aircraft . The technique , results , and lessons learned from a detailed End - to - End Verification and Validation ( E2 - V2 ) simulation study of a DAA system representative of RTCA SC-228 's proposed Phase I DAA Minimum Operational Performance Standards ( MOPS ) , based on specific test vectors and encounter cases , will be presented in this paper .
Preliminary analyses of the POLSCAT data acquired from the CLPX - II in winter 2006 - 2007 are described in this paper . The data showed the response of the Ku - band radarechoes to snowpack changes for various types of background vegetation . We observed about 0.2 to 0.4 dB increases in backscatter for every 1 cm SWE accumulation for sage brush and agricultural fields . The co - polarized VV and HH radar resposnes are similar , while the corss - polarized ( VH or HV ) echoes showedgreater resposne to the change of SWE . The data also showed the impact of surface hoar growth and freeze / thaw cycles , whichcreated large snow grain sizes and ice lenses , respectively , and consequently increased the radar signals by a few dBs .
One of the factor that derives the performance of small inner working angle ( IWA ) coronagraphs is the quality of the low - order wavefront calibration and control . The uncorrected residuals scatter the starlight and produces intensity fluctuations , which as a result creates dynamic speckle noise in the focal plane . To improve post processing of the science images , the low - order telemetry of the residuals left uncorrected by the control loop can be used to calibrate the amount of starlight leakage at small angular separations . In this proceeding , we present the preliminary simulations of point spread function calibration using the Lyot - based low - order wavefront sensor measurements ( tip - tilt only ) for a vector vortex coronagraph .
A new queuing model is being developed to evaluate the capacity benefits of several new concepts for terminal airspace operations . The major innovation is the ability to support a wide variety of multiple constraints for modeling the scheduling logic of several concepts . Among the constraints modeled are in - trail separation , separation between aircraft landing on parallel runways , in - trail separation at terminal area entry points , and permissible terminal area flight times .
EXOS is the charged - particle spectrometer on EXOCUBE that will measure the H / He / O and H+ /He+ /0 + densities and temperatures in the exosphere . Its basic approach is based on WINCS ; however , EXOS gave the impetus for improvements that led to the 2nd generation WINCS . Beginning with a brief description of the WINCS methodology for ionosphere - thermosphere measurements , lessons learned from the first generation WINCS are summarized as introduction to the design of EXOS . The EXOS design is then presented and discussed .
This paper describes a new reconfigurable analog array ( MA ) architecture and integrated circuit ( IC ) used to map analog circuits that can adapt to extreme temperatures under programmable control . Algorithm - driven adaptation takes place on the RAA IC . The algorithms are implemented in a separate Field Programmable Gate Array ( FPGA ) IC , co - located with the RAA in the extreme temperature environment . The experiments demonstrate circuit adaptation over a wide temperature range , from extremely low temperature of -180 C to high 120 C.
The goals of this project are to : Develop an early lifecycle software cost estimation tool leveraging existing data and capabilities Collect additional software data from : a ) Jet Propulsion Laboratory ; b ) Goddard Space Flight Center ; and c ) Marshall Space Flight Center . Analyze , normalize , evaluate , stratify , and validate data . Create a calibrated , validated , and documented tool initially using available data and subsequently using newly collected data .
Large space deployable antennas are needed for a variety of applications that include Mobile Communications , Radiometry , Active Microwave Sensing , Very Long Baseline Interferometry and   DoD Space Based Radar .   These user requirements identify the need for structures up to tens of meters in size for operation from 1 to 90 GHz , based on different aperture configurations .    However , the one thing the users have in common is a concept selection criteria for low cost , light weight and highly reliable deployable structures .   Fortunately , a unique class of   space structures has recently emerged that have tremendous potential for satisfying these criteria .   They are referred to as inflatable deployable structures .
This paper considers factors that contribute to poor identification of unsteady aerodynamics from wind tunnel data for an airliner configuration . One approach to modeling a wing - tail configuration is considered and applied to both steady and large - amplitude forced pitch oscillation wind tunnel data taken over a wide range of angles of attack but a limited range of amplitude and frequencies . The identified models fit the measured data well but in some cases with inaccurate parameters . Only limited conclusions can be drawn from analysis of the current data set until further experiments can be performed to resolve the identification issues . The analysis of measured and simulated data provides some insights and guidance on how an effective experiment may be designed for wing - tail configurations with nonlinear unsteady aerodynamics .
Lunar resonant orbits present several important challenges in terms of trajectory design , insertion , stability and eclipse mitigation . For some mission concepts , the placement of the initial orbital elements is fundamental to overcoming show - stopping performance values such as eclipse duration and orbit lifetime . Lunar resonant orbits need to maintain specific alignments in order to avoid undesired flybys or even recontact with Earth or GEO satellites . This paper presents methods to mitigate long eclipses while preserving achievable lunar resonant orbits that persist in the long term .
NASA 's Exploration Systems Mission Directorate ( ESMD ) is implementing a management approach for modeling and simulation ( M&S ) that will provide decision - makers information on the model 's fidelity , credibility , and quality . This information will allow the decision - maker to understand the risks involved in using a model 's results in the decision - making process . This presentation will discuss NASA 's approach for verification and validation ( V&V ) of its models or simulations supporting space exploration . This presentation will describe NASA 's V&V process and the associated M&S verification and validation ( V&V ) activities required to support the decision - making process . The M&S V&V Plan and V&V Report templates for ESMD will also be illustrated .
Many software systems are evolving complex system of systems ( SoS ) for which inter - system communication is both mission - critical and error - prone . Such communication problems ideally would be detected before deployment . In a NASA - supported Software Assurance Research Program ( SARP ) project , we are researching a new approach addressing such problems . In this paper , we show that problems in the communication between two systems can be detected by using sequence diagrams to model the planned communication and by comparing the planned sequence to the actual sequence . We identify different kinds of problems that can be addressed by modeling the planned sequence using different level of abstractions .
This paper describes the use of an Eulerian Dispersed Phase ( EDP ) model to simulate the water injected from the flame deflector and its interaction with supersonic rocket exhaust from a proposed Space Launch System ( SLS ) vehicle . The Eulerian formulation , as part of the multi - phase framework , is described . The simulations show that water cooling is only effective over the region under the liquid engines . Likewise , the water injection provides only minor effects over the surface area under the solid engines .
For over two decades , astronomers have considered the possibilities for interferometry in space . The first of these missions was the Space Interferometry Mission ( SIM ) , but that was followed by missions for studying exoplanets ( e.g Terrestrial Planet Finder , Darwin ) , and then far - infrared interferometers ( e.g. the Space Infrared Interferometric Telescope , the Far - Infrared Interferometer ) . Unfortunately , following the cancellation of SIM , the future for space - based interferometry has been in doubt , and the interferometric community needs to reevaluate the path forward . While interferometers have strong potential for scientific discovery , there are technological developments still needed , and continued maturation of techniques is important for advocacy to the broader astronomical community . We review the status of several concepts for space - based interferometry , and look for possible synergies between missions oriented towards different science goals .
The observed hard X - ray temporal and spectral characteristics will be displayed for over nine years of BATSE ( Burst and Transient Source Experiment ) data from the Compton Observatory . These observations were obtained using the Earth occultation technique , a technique that has become increasingly more sensitive and accurate as systematic effects are understood and corrected . The principal objects that are being presented in this study include : GRO J1655 - 40 , GRS 1915 + 105 , Cyg X-3 , Cyg X-1 , XTE J1550 - 564 , XTE J1859 + 226 , XTE J1748 - 288 , and V4641 Sgr . Light curves and spectral will be presented and discussed in terms of relativistic jet production in these systems .