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Active Aircraft Pylon Noise Control System
Unmanned Aerial Systems Traffic Management
Method of Bonding Dissimilar Materials
Sonar Inspection Robot System
Applying the Dynamic Inertia Measurement Method to Full-Scale Aerospace Vehicles
Method and Apparatus for Measuring Surface Air Pressure
Fully Premixed, Low-Emission, High-Pressure, Multi-Fuel Burner
Self-Healing Wire Insulation
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Robustness Analysis and Robust Design of Uncertain Systems

Langley Research Center, Hampton, Virginia A methodology was developed for the analysis and design of systems subject to parametric uncertainty in which design requirements are specified via hard inequality constraints. Hard constraints are those that must be satisfied for all parameter realizations within a given uncertainty model. Uncertainty models are given by norm-bounded perturbations from a nominal parameter value (i.e., hyperspheres) and by sets of independently bounded uncertain variables (i.e., hyperrectangles). These models, which are also quite practical, allow for a rigorous mathematical treatment within the proposed framework. Hardconstraint feasibility is determined by sizing the largest uncertainty set for which the design requirements are satisfied.

Posted in: Briefs, Electronics & Computers, Software

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XDB3 Extension for Equality and Relational Operators

Ames Research Center, Moffett Field, California While keyword full-text searches work well for textual data, they do not work well for numeric, date, or other more highly structured information. In particular, Netmark/XDB could retrieve any record where the author contained “Knight” in the text, but could not return only those records from Calendar Year 2010 that have “Knight” in their author section. Traditional relational databases allow for rich comparison “relational” operators; for example, one can express a query such as “return all rows where the signature date is on January 1, 2010.” Netmark/XDB, being primarily targeted at XML processing and retrieving XML-structured data, was designed for full-text querying to find keywords. Most other XML indexing and querying systems also are designed with the assumption that content (“CDATA”) is textual or binary data that can be queried against, but not with relational comparison operators like “greater than a value.”

Posted in: Briefs, Electronics & Computers, Software

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Simulator for a Self-Stabilizing Synchronization Protocol for Arbitrary Digraphs

Langley Research Center, Hampton, Virginia This work was conducted to create a means of simulating and visualizing the behavior of a self-stabilizing distributed clock synchronization protocol developed at LaRC (Langley Research Center). The protocol has many applications including projects that directly pertain to work being done at NASA. Time synchronization is a critical component of many projects, from computer networking and distributed systems, to autonomous flight. This easy-to-understand interface both displays accurate information concerning the protocol, and conveys its utility.

Posted in: Briefs, Electronics & Computers, Software

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Testing Encapsulation of Internet, DTN, and LTP Traffic over AOS Space Data Link Protocol

NASA’s Jet Propulsion Laboratory, Pasadena, California The CCSDS ENCAP Over AOS Over UDP software engine encapsulates live Internet Protocol (IP), DTN Bundle Protocol (BP), or Licklider Transport Protocol (LTP) traffic over a Consultative Committee for Space Data Systems (CCSDS)-compliant Encapsulation Ser vice (ENCAP) running over an Advanced Orbiting Systems (AOS) data link protocol UDP stream. Many space missions currently use the AOS protocol, and this software is an implementation of a standard mechanism to encapsulate Internet Protocol traffic (including interactive Web applications and streaming video) and DTN Bundle Protocol traffic (for large file transfers over high latency links) over ENCAP over AOS.

Posted in: Briefs, Electronics & Computers, Software

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Thinking About Switching CAD Platforms? Check out this report.

As CAD vendors adjust their licensing and software models and as your business deals with staffing and marketing changes it only makes sense to re-assess software requirements. With this report from Tech Clarity, you’ll have a fantastic guide to leverage on your journey.  Now you’ll have all the critical factors to consider when assessing your CAD platform. The in-depth examination covers topics such as: * Why change; * Setting organizational expectations; and * What’s import to leading CAD users.

Posted in: White Papers, Electronics & Computers, Manufacturing & Prototyping, Software

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Using Static Analysis to Overcome the Challenges of Reusing Code for Embedded Software

This paper explains why software reuse is a growing problem within development organizations, why the way embedded software is developed needs to change and what organizations can do to improve reliability, safety, and security while reducing development time. Gain a better understanding of:

Posted in: White Papers, Aeronautics, Electronics & Computers, Semiconductors & ICs, Electronics & Computers, Software

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A Guide to the MISRA Coding Standard: What you need to know

This white paper will provide your development organization with the critical information needed to adopt MISRA the standard and to quickly update code review practices and documentation efforts.

Posted in: White Papers, Aeronautics, Electronics & Computers, Semiconductors & ICs, Electronics & Computers, Software

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