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At least 37 records · Page 2

Developing Standards for AI/ML Systems in Civil Aviation: Challenges and Barriers

The inability to establish appropriate assurance methods for AI/ML components in safety critical systems leaves us unable to effectively manage the risks and benefits of such systems. It drives cost of development for systems with AI/ML components uneconomically high, it delays the adoption of systems with AI/ML components at scale, and it can result in catastrophic consequences in terms of the safety of systems with AI/ML components. In this presentation we will explore what constitutes sufficient scientific-based evidence to substantiate a safety claim related to an AI/ML component performing a safety-critical function.

AI/ML Standards↗

NASA Occupant Protection Standards Development

Historically, spacecraft landing systems have been tested with human volunteers, because analytical methods for estimating injury risk were insufficient. These tests were conducted with flight-like suits and seats to verify the safety of the landing systems. Currently, NASA uses the Brinkley Dynamic Response Index to estimate injury risk, although applying it to the NASA environment has drawbacks: (1) Does not indicate severity or anatomical location of injury (2) Unclear if model applies to NASA applications. Because of these limitations, a new validated, analytical approach was desired. Leveraging off of the current state of the art in automotive safety and racing, a new approach was developed. The approach has several aspects: (1) Define the acceptable level of injury risk by injury severity (2) Determine the appropriate human surrogate for testing and modeling (3) Mine existing human injury data to determine appropriate Injury Assessment Reference Values (IARV). (4) Rigorously Validate the IARVs with sub-injurious human testing (5) Use validated IARVs to update standards and vehicle requirement

Somers, Jeffrey↗

Developing Standards for Phtotvoltaic Devices

Ground rules outlined for evaluating photovoltaic technology. Document addresses number of performance attributes: electrical, thermal, mechanical, structural, safety, reliability, durability, installation, operation, maintenance, building and site. Each criterion includes user need or expectation for element and describes method of test.

Hoffman, A. R.↗

NEMA wire and cable standards development programs

The National Electrical Manufacturers Association (NEMA) is the nation's largest trade association for manufacturers of electrical equipment. Its member companies produce components, end-use equipment and systems for the generation, transmission, distribution, control and use of electricity. The wire and cable division is presented in 6 sections: building wire and cable, fabricated conductors, flexible cords, high performance wire and cable, magnet wire, and power and control cable. Participating companies are listed.

Baird, Robert W.↗

Mass Properties for Space Systems Standards Development

Current Verbiage in S-120 Applies to Dry Mass. Mass Margin is difference between Required Mass and Predicted Mass. Performance Margin is difference between Predicted Performance and Required Performance. Performance estimates and corresponding margin should be based on Predicted Mass (and other inputs). Contractor Mass Margin reserved from Performance Margin. Remaining performance margin allocated according to mass partials. Compliance can be evaluated effectively by comparison of three areas (preferably on a single sheet). Basic and Predicted Mass (including historical trend). Aggregate potential changes (threats and opportunities) which gives Mass Forecast. Mass Maturity by category (Estimated/Calculated/Actual).

Beech, Geoffrey↗

ASTM E399 Standard Development - KIsi Analysis Method

The ASTM E399 test method is used to determine the plane‐strain fracture toughness, K (sub IC), for metallic materials. The test consists of monotonically loading a pre-cracked test specimen to failure while recording the applied load and the crack mouth opening displacement. Several test specimen types are allowable per ASTM E399; two common geometries are the compact tension (C(T)) and the single-edge bend (SE(B)) geometries. The test result is an estimate of the plane‐strain fracture toughness, K (sub q), determined by the intercept of the test record with a 95 percent secant-offset construction line. The 95 percent offset represents crack extension corresponding to approximately 2 percent of the original specimen ligament (assuming that all compliance change is the result of crack extension). If the test meets certain validity requirements based on specimen size and test behavior, the result is valid, and K (sub q) equals K (sub IC).

Tilson, William G.↗

The USL NASA PC R and D development environment standards

The development environment standards which have been established in order to control usage of the IBM PC/XT development systems and to prevent interference between projects being currently developed on the PC's are discussed. The standards address the following areas: scheduling PC resources; login/logout procedures; training; file naming conventions; hard disk organization; diskette care; backup procedures; and copying policies.

Dominick, Wayne D.↗

NASA’s Plans for Development of Standards for Additive Manufactured Components

There are currently no NASA standards providing specific design and construction requirements for certification of additively manufactured parts. Several international standards organizations are developing standards for additive manufacturing; however, NASA mission schedules preclude the Agency from relying on these organizations to develop standards that are both timely and applicable. NASA and its program partners in manned spaceflight (the Commercial Crew Program, the Space Launch System and the Orion Multi-purpose Crew Vehicle) are actively developing additively manufactured parts for flight as early as 2018. To bridge this gap, NASA Marshall Space Flight Center (MSFC) has authored a center-level standard (MSFC-STD-3716)1 to establish standard practices for the Laser Powder Bed Fusion (L-PBF) process. In its draft form, the MSFC standard has been used as a basis for L-PBF process implementation for each of the manned space flight programs. The development of an Agency-level standard is proposed, which based upon the principles of MSFC-STD-3716, would have application to multiple additive manufacturing processes and be readily adaptable to all NASA programs.

Russell, Richard W.↗