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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 235 records · Page 13
All sourcesNASA NTRSDOE OSTI
DOE OSTI2017

WCM water content for ACE-ENA

The WCM-2000, manufactured by Science Engineering Associates (SEA), is a multi-element water content measuring system that measures both liquid water content (LWC) and total water content (TWC), allowing the inference of ice water content (IWC). The TWC is measured by a scoop-shaped sensor that collects both liquid and ice phase hydrometeors. The WCM-2000 also has two heated wire elements that are exposed directly to the airstream and a reference or compensation element that is exposed to the airflow but not the condensed water. The two heated wires measure the LWC for different size droplets and are sized to match the Johnson-Williams (JW) (021 Wire) LWC probe (0.5 mm; Neel 1955) and the King (083 Wire) probe (2 mm; King et al. 1978). The WCM-2000 is calibrated according to the manufacturer instructions, which involve a dedicated test flight in cloud-free air. Each flight is also corrected for zero-offset bias using clear-air measurements

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2018

Radiometer for ACE-ENA

The broadband SPN total, zenith1, and zenith2 downwelling SW irradiances were corrected for tilt up to 10 degrees of tilt (per Long et al., 2010). For tilt greater than 10 degrees these values are set to ""bad"". No tilt correction has been applied to the MFR spectral data.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2018

AIMMS 20 Hz ACE-ENA

The AIMMS-20 probe is manufactured by Aventech Research Inc. (http://www.aventech.com) and measures platform position, velocity, attitude, and ambient temperature, static pressure, and the differential pressures from a 5-port hemispheric gust probe, and combines all these measured data into a calculation of the ambient winds. A detailed description of the AIMMS-20 specifications is available on (http://aventech.com/documents/PMS%20CANISTER/PMS%20Canister%20Technical%20Specifications.pdf). The data provided here are originally communicated as raw measurements over the CAN bus to the ODMS data module and stored in flight in binary .rXX files. These files are combined in post processing using the Aventech program asmbl.exe in to .raw files, one for each flight. The .raw files are subsequently processed using the Aventech program ekf553_oemv.exe, which regenerates the wind estimates, in this case at an output rate of 20 Hz.

54 ENVIRONMENTAL SCIENCES↗
NASA NTRS2015

Appendix A: NAS-Wide Encounter Rate Evaluation Using Historical Radar Data and the Airspace Concept Evaluation System (ACES)

Regulations that establish operational and performance requirements for unmanned aircraft systems (UAS) are being developed by a consortium of government, industry and academic institutions. Those requirements will apply to detect-and-avoid (DAA) systems and other equipment necessary to integrate UAS with the National Airspace System (NAS) and are determined according to their contribution to the overall level of safety required to operate in the airspace. Several key gaps must be addressed in order to link equipment requirements to an airspace level of safety. Foremost among these is the calculation of the relative effectiveness of a particular system to mitigate violations of a separation standard with other aircraft, which is known as the systems risk ratio. The risk ratio is calculated as the probability of mid-air collision with a DAA system divided by the probability of mid-air collision without a DAA system. The risk ratio of a DAA system, in combination with the risk ratios of other collision avoidance mitigations, will determine the overall safety of the airspace measured in terms of the number of mid-air collisions per flight hour. Defining the required risk ratio that the DAA system needs to ensure the safety of the airspace requires an evaluation of the current airspace and a simulated evaluation that incorporates UAS aerodynamic performance and the mission characteristics of future UAS operations that are projected to be conducted in areas that interact with current operations. These evaluations will produce the frequency of encounters that currently exist in the airspace and those that could be generated with the introduction of UAS. Together, the frequency of encounters, an evaluation of unmitigated risk of collision, and a desired level of safety of the airspace will yield a required risk ratio of the DAA system. This study will focus on evaluating the encounter rates between aircraft based on historical radar data and encounter rates that could occur based on simulated UAS missions.

Unmanned Aircraft Systems↗
DOE OSTI2012

SPATIALLY DEPENDENT HEATING AND IONIZATION IN AN ICME OBSERVED BY BOTH ACE AND ULYSSES

The 2005 January 21 interplanetary coronal mass ejection (ICME) observed by multiple spacecraft at L1 was also observed from January 21-February 4 at Ulysses (5.3 AU). Previous studies of this ICME have found evidence suggesting that the flanks of a magnetic cloud like structure associated with this ICME were observed at L1 while a more central cut through the associated magnetic cloud was observed at Ulysses. This event allows us to study spatial variation across the ICME and relate it to the eruption at the Sun. In order to examine the spatial dependence of the heating in this ICME, we present an analysis and comparison of the heavy ion composition observed during the passage of the ICME at L1 and at Ulysses. Using SWICS, we compare the heavy ion composition across the two different observation cuts through the ICME and compare it with predictions for heating during the eruption based on models of the time-dependent ionization balance throughout the event.

79 ASTRONOMY AND ASTROPHYSICS↗