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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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22 records · Page 2

Identity Federation and Its Importance for NASA's Future: The SharePoint Extranet Pilot

My project at Kennedy Space Center (KSC) during the spring 2013 Project Management and Systems Engineering Internship was to functionalJy test and deploy the SharePoint Extranet system and ensure successful completion of the project's various lifecycle milestones as described by NASA Procedural Requirement (NPR) 7 120.7. I worked alongside NASA Project Managers, Systems Integration Engineers, and Information Technology (IT) Professionals to pilot this collaboration capability between NASA and its External Partners. The use of identity federation allows NASA to leverage externally-issued credentials of other federal agencies and private aerospace and defense companies, versus the traditional process of granting and maintaining full NASA identities for these individuals. This is the first system of its kind at NASA and it will serve as a pilot for the Federal Government. Recognizing the novelty of this service, NASA's initial approach for deployment included a pilot period where nearby employees of Patrick Air Force Base would assist in testing and deployment. By utilizing a credential registration process, Air Force users mapped their Air Force-issued Common Access Cards (CAC) to a NASA identity for access to the External SharePoint. Once the Air Force stands up an Active Directory Federation Services (ADFS) instance within their Data Center and establishes a direct trust with NASA, true identity federation can be established. The next partner NASA is targeting for collaboration is Lockheed Martin (LMCO), since they collaborate frequently for the ORION Program. Through the use of Exostar as an identity hub, LMCO employees will be able to access NASA data on a need to know basis, with NASA ultimately managing access. In a time when every dollar and resource is being scrutinized, this capability is an exciting new way for NASA to continue its collaboration efforts in a cost and resource effective manner.

Baturin, Rebecca R.↗

Association Between Increased Vascular Density and Loss of Protective RAS in Early-stage NPDR

Our hypothesis predicts that retinal blood vessels increase in density during early-stage progression to moderate nonproliferative diabetic retinopathy (NPDR). The renin-angiotensin system (RAS) is implicated in the pathogenesis of DR and in the function of circulating angiogenic cells (CACs), a critical bone marrow-derived population that is instrumental in vascular repair.

Fractal↗

NASA Screening and Clinical Practice for the Monitoring and Mitigation of Coronary Artery Disease: Application to Terrestrial Practice

Coronary artery disease (CAD) surveillance has led to the development of risk stratification tools that drive clinical mitigation efforts for CAD risk. As common risk assessment tools, including the Framingham Risk Score (FRS) or Pooled Cohort Risk Equations, have insufficient accuracy on an individual level to meet NASA’s stringent screening guidelines, NASA has required new approaches to address the risk of catastrophic cardiovascular (CV) medical events among astronauts. Coronary artery calcium (CAC) scanning has emerged as the current best tool to enhance CV risk assessment in asymptomatic individuals, with risk information incremental to FRS data.

Khera, Amit↗

Interference Mitigation Using Cyclic Autocorrelation and Multi-Objective Optimization

Radio frequency interference on space-to-ground communications links can degrade performance and disrupt the transfer of critical data. These interference events become increasingly likely as more users enter the spectrum, due in part to shared spectrum allocations and scheduling conflicts. If this interference could be detected and mitigated by an automated system, then link performance and reliability in these scenarios could be improved. This report describes the implementation and evaluation of an automated interference mitigation system that provides this functionality. The system uses Cyclic Autocorrelation (CAC) signal processing techniques to monitor the spectrum and detect interfering signals, and it applies a multi-objective optimization approach to mitigate interference by changing link parameters to continuously optimize the link. The implementation was evaluated to characterize its signal detection capabilities for various link qualities and to compare its link management performance to Adaptive Coding and Modulation (ACM) and Constant Coding and Modulation (CCM) when in the presence of randomized interference. In the latter evaluation, the interference mitigation system achieved the highest average throughput in each tested scenario. With these results, the proposed solution provides the groundwork for further automated link management capabilities and continued investigation into interference mitigation approaches.

Interference mitigation↗