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Increment 59-60 Science Symposium presentation of Advanced Colloids Experiment (ACE-T10) (by GRC (Glenn Research Center) to the RPO-JSC (Research Planning Office-Johnson Space Center), via WebEx. The purpose of this event is for Principal Investigators to present their science objectives, testing approach, and measurement methods to agency scientists, managers, and other investigators.
Realization of the expected proliferation of Unmanned Aircraft System (UAS) operations in the National Airspace System (NAS) depends on the development and validation of performance standards for UAS Detect and Avoid (DAA) Systems. The RTCA Special Committee 228 (SC-228) is charged with leading the development of draft Minimum Operational Performance Standards (MOPS) for UAS DAA Systems. NASA, as a participating member of RTCA SC-228 is committed to supporting the development and validation of draft requirements as well as the safety substantiation and end-to-end assessment of DAA system performance. With regard to the safety aspect being studied by the SC-228 DAA Safety sub-group, NASA has conducted a study using the ACES (Airspace Concept Evaluation System) simulation capability to determine: 1) the rate at which IFR aircraft encounter other IFR and VFR aircraft, and 2) the rate at which UAS aircraft encounter VFR aircraft as well as the corresponding encounter geometries. Five different separation thresholds were used (two for encounter and one each for well-clear, near mid-air collision, and closest point of approach). The results will be used by the SC-228 DAA Safety sub-group to inform decisions about the safety aspect of UAS DAA systems and future requirements development and validation efforts.
Increment 59-60 Science Symposium presentation of Advanced Colloids Experiment (ACE-T10) (by GRC (Glenn Research Center) to the RPO-JSC (Research Planning Office-Johnson Space Center), via WebEx. The purpose of this event is for Principal Investigators to present their science objectives, testing approach, and measurement methods to agency scientists, managers, and other investigators.
The attached will be presented at the JSC Science Symposium as a preview of the ACE-T5 flight experiment. The Principal Investigator (PI) for this experiment is Professor Ali Mohraz at the University of California - Irvine.Bijels (bicontinuous interfacially jammed emulsion gels) were discovered in 2007 at the University of Edinburgh. These materials feature a tubular, bicontinuous arrangement of two fluid phases separated by a monolayer of jammed colloidal particles at the interface.Because of their unique morphological characteristics, bijels hold significant promise as next-generation materials for energy and biotechnology applications. But in order to fully realize their potential, their physics and mechanical properties must be better understood. The mechanical properties and stability of bijels is mediated by an interplay between interfacial forces that impart elasticity to the system, and external stresses. Unfortunately, the interfacial forces are inherently coupled with density differences and cannot be studied systematically in the presence of gravity.
Two-dimensional position-sensitive silicon detectors (matrix detectors) have been designed, procured, and tested as part of the development of the Solar Isotope Spectrometer (SIS) instrument for NASA's Advanced Composition Explorer (ACE) mission. Important characteristics of these devices include: thickness approx. 50-90µm, active area 34 cm 2 , 64 strips on each surface with 1 mm strip pitch.
We report on extensive tests of large-area (10cm diameter) high-purity ion-implanted silicon detectors for th Solar Isotope Spectrometer (SIS), and lithium-drifted silicon detetors for the Cosmic Ray Isotope Spectrometer (CRIS), which are under development for launch on the Advanced Composition Explorer (ACE) mission.
In this paper we illustrate the unique dataset collected during the Global Precipitation Measurement Cold-season Precipitation Experiment (GCPEx, US/Canada Jan/Feb 2012). We will focus on the significance of these observations for the development of algorithms for GPM and ACE, with particular attention to classification and retrievals of frozen and mixed phase hydrometeors.
ISS Increment 65 Science Symposium Advanced Colloids Experiment (Temperature controlled) – ACE-T11(R)
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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.
On August 30, 2024, the National Nuclear Data Center (NNDC) released the ENDF/B-VIII.1 nuclear data library [1]. The library was released in the standard Evaluated Nuclear Data File (ENDF) format.