<?xml version="1.0" encoding="UTF-8"?>
<rss version="2.0" xmlns:atom="http://www.w3.org/2005/Atom"><channel><title>New NASA STI Report Series</title><link>http://www.sti.nasa.gov</link><description><![CDATA[Today's Listing of New NASA STI Report Series in the NASA Aeronautics and Space Database.]]></description><language>en-us</language><lastBuildDate>Wed, 19 Jun 2013 06:59:22 GMT</lastBuildDate><atom:link href="http://www.sti.nasa.gov/scan/rss99-02.xml" rel="self" type="application/rss+xml"/><image><title>New NASA STI Report Series</title><url>http://www.sti.nasa.gov/3Dmeatball.jpg</url><link>http://www.sti.nasa.gov</link></image><item><title>Validation of Helicopter Gear Condition Indicators Using Seeded Fault Tests</title><link>http://ntrs.nasa.gov/search.jsp?R=20130013685</link><description><![CDATA[Abstract: A "seeded fault test" in support of a rotorcraft condition based maintenance program (CBM), is an experiment in which a component is tested with a known fault while health monitoring data is collected. These tests are performed at operating conditions comparable to operating conditions the component would be exposed to while installed on the aircraft. Performance of seeded fault tests is one method used to provide evidence that a Health Usage Monitoring System (HUMS) can replace current maint...]]></description><pubDate>Tue, 18 Jun 2013 00:00:00 GMT</pubDate><guid>http://ntrs.nasa.gov/search.jsp?R=20130013685</guid></item><item><title>Impact Testing of Aluminum 2024 and Titanium 6Al-4V for Material Model Development</title><link>http://ntrs.nasa.gov/search.jsp?R=20130013684</link><description><![CDATA[Abstract: One of the difficulties with developing and verifying accurate impact models is that parameters such as high strain rate material properties, failure modes, static properties, and impact test measurements are often obtained from a variety of different sources using different materials, with little control over consistency among the different sources. In addition there is often a lack of quantitative measurements in impact tests to which the models can be compared. To alleviate some of these p...]]></description><pubDate>Tue, 18 Jun 2013 00:00:00 GMT</pubDate><guid>http://ntrs.nasa.gov/search.jsp?R=20130013684</guid></item><item><title>Effects of Microstructural Parameters on Creep of Nickel-Base Superalloy Single Crystals</title><link>http://ntrs.nasa.gov/search.jsp?R=20130013683</link><description><![CDATA[Abstract: Microstructure-sensitive creep models have been developed for Ni-base superalloy single crystals. Creep rupture testing was conducted on fourteen single crystal alloys at two applied stress levels at each of two temperatures, 982 and 1093 C. The variation in creep lives among the different alloys could be explained with regression models containing relatively few microstructural parameters. At 982 C, gamma-gamma prime lattice mismatch, gamma prime volume fraction, and initial gamma prime size...]]></description><pubDate>Tue, 18 Jun 2013 00:00:00 GMT</pubDate><guid>http://ntrs.nasa.gov/search.jsp?R=20130013683</guid></item><item><title>Method for Estimating Operational Loads on Aerospace Structures Using Span-Wisely Distributed Surface Strains</title><link>http://ntrs.nasa.gov/search.jsp?R=20130013606</link><description><![CDATA[Abstract: This report presents a new method for estimating operational loads (bending moments, shear loads, and torques) acting on slender aerospace structures using distributed surface strains (unidirectional strains). The surface strain-sensing stations are to be evenly distributed along each span-wise strain-sensing line. A depth-wise cross section of the structure along each strain-sensing line can then be considered as an imaginary embedded beam. The embedded beam was first evenly divided into mul...]]></description><pubDate>Wed, 05 Jun 2013 00:00:00 GMT</pubDate><guid>http://ntrs.nasa.gov/search.jsp?R=20130013606</guid></item><item><title>Structural Analysis Peer Review for the Static Display of the Orbiter Atlantis at the Kennedy Space Center Visitors Center</title><link>http://ntrs.nasa.gov/search.jsp?R=20130013597</link><description><![CDATA[Abstract: Mr. Christopher Miller with the Kennedy Space Center (KSC) NASA Safety & Mission Assurance (S&MA) office requested the NASA Engineering and Safety Center's (NESC) technical support on March 15, 2012, to review and make recommendations on the structural analysis being performed for the Orbiter Atlantis static display at the KSC Visitor Center. The principal focus of the assessment was to review the engineering firm's structural analysis for lifting and aligning the orbiter and its static displ...]]></description><pubDate>Mon, 03 Jun 2013 00:00:00 GMT</pubDate><guid>http://ntrs.nasa.gov/search.jsp?R=20130013597</guid></item><item><title>Composite Crew Module (CCM) Permeability Characterization</title><link>http://ntrs.nasa.gov/search.jsp?R=20130013592</link><description><![CDATA[Abstract: In January 2007, the NASA Administrator chartered the NASA Engineering and Safety Center (NESC) to form an Agency team to design and build a composite crew module in 18 months in order to gain hands-on experience in anticipation that future exploration systems may be made of composite materials. One of the conclusions from this Composite Crew Module Primary Structure assessment was that there was a lack of understanding regarding the ability for composite pressure shells to contain consumable...]]></description><pubDate>Mon, 03 Jun 2013 00:00:00 GMT</pubDate><guid>http://ntrs.nasa.gov/search.jsp?R=20130013592</guid></item><item><title>Composite Materials With Uncured Epoxy Matrix Exposed in Stratosphere During NASA Stratospheric Balloon Flight</title><link>http://ntrs.nasa.gov/search.jsp?R=20130013590</link><description><![CDATA[Abstract: A cassette of uncured composite materials with epoxy resin matrixes was exposed in the stratosphere (40 km altitude) over three days. Temperature variations of -76 to 32.5C and pressure up to 2.1 torr were recorded during flight. An analysis of the chemical structure of the composites showed, that the polymer matrix exposed in the stratosphere becomes crosslinked, while the ground control materials react by way of polymerization reaction of epoxy groups. The space irradiations are considered ...]]></description><pubDate>Mon, 03 Jun 2013 00:00:00 GMT</pubDate><guid>http://ntrs.nasa.gov/search.jsp?R=20130013590</guid></item><item><title>Mars Sample Return: Mars Ascent Vehicle Mission and Technology Requirements</title><link>http://ntrs.nasa.gov/search.jsp?R=20130013542</link><description><![CDATA[Abstract: A Mars Sample Return mission is the highest priority science mission for the next decade recommended by the recent Decadal Survey of Planetary Science, the key community input process that guides NASA's science missions. A feasibility study was conducted of a potentially simple and low cost approach to Mars Sample Return mission enabled by the use of new commercial capabilities. Previous studies of MSR have shown that landing an all up sample return mission with a high mass capacity lander is...]]></description><pubDate>Thu, 30 May 2013 00:00:00 GMT</pubDate><guid>http://ntrs.nasa.gov/search.jsp?R=20130013542</guid></item><item><title>Large-Scale Liquid Hydrogen Tank Rapid Chill and Fill Testing for the Advanced Shuttle Upper Stage Concept</title><link>http://ntrs.nasa.gov/search.jsp?R=20130013526</link><description><![CDATA[Abstract: Cryogenic upper stages in the Space Shuttle program were prohibited primarily due to a safety risk of a 'return to launch site' abort. An upper stage concept addressed this concern by proposing that the stage be launched empty and filled using shuttle external tank residuals after the atmospheric pressure could no longer sustain an explosion. However, only about 5 minutes was allowed for tank fill. Liquid hydrogen testing was conducted within a near-ambient environment using the multipurpose ...]]></description><pubDate>Fri, 24 May 2013 00:00:00 GMT</pubDate><guid>http://ntrs.nasa.gov/search.jsp?R=20130013526</guid></item><item><title>Ultrasonic Nondestructive Evaluation of PRSEUS Pressure Cube Article in Support of Load Test to Failure</title><link>http://ntrs.nasa.gov/search.jsp?R=20130013480</link><description><![CDATA[Abstract: The PRSEUS Pressure Cube Test was a joint development effort between the Boeing Company and NASA Langley Research Center, sponsored in part by the Environmentally Responsible Aviation Project and Boeing internal R&D. This Technical Memorandum presents the results of ultrasonic inspections in support of the PRSEUS Pressure Cube Test, and is a companion document with the NASA test report and a report on the acoustic emission measurements made during the test.]]></description><pubDate>Tue, 21 May 2013 00:00:00 GMT</pubDate><guid>http://ntrs.nasa.gov/search.jsp?R=20130013480</guid></item><item><title>PRSEUS Pressure Cube Test Data and Response</title><link>http://ntrs.nasa.gov/search.jsp?R=20130013479</link><description><![CDATA[Abstract: NASA s Environmentally Responsible Aviation (ERA) Program is examining the hybrid wing body (HWB) aircraft, among others, in an effort to increase the fuel efficiency of commercial aircraft. The HWB design combines features of a flying wing with features of conventional transport aircraft, and has the advantage of simultaneously increasing both fuel efficiency and payload. Recent years have seen an increased focus on the structural performance of the HWB. The key structural challenge of a HWB...]]></description><pubDate>Tue, 21 May 2013 00:00:00 GMT</pubDate><guid>http://ntrs.nasa.gov/search.jsp?R=20130013479</guid></item><item><title>NASA Software Engineering Benchmarking Study</title><link>http://ntrs.nasa.gov/search.jsp?R=20130013477</link><description><![CDATA[Abstract: To identify best practices for the improvement of software engineering on projects, NASA's Offices of Chief Engineer (OCE) and Safety and Mission Assurance (OSMA) formed a team led by Heather Rarick and Sally Godfrey to conduct this benchmarking study. The primary goals of the study are to identify best practices that: Improve the management and technical development of software intensive systems; Have a track record of successful deployment by aerospace industries, universities [including re...]]></description><pubDate>Tue, 21 May 2013 00:00:00 GMT</pubDate><guid>http://ntrs.nasa.gov/search.jsp?R=20130013477</guid></item><item><title>Motorized Beam Alignment of a Commercial X-ray Diffractometer</title><link>http://ntrs.nasa.gov/search.jsp?R=20130013469</link><description><![CDATA[Abstract: X-ray diffraction (XRD) is a powerful analysis method that allows researchers to noninvasively probe the crystalline structure of a material. This includes the ability to determine the crystalline phases present, quantify surface residual stresses, and measure the distribution of crystallographic orientations. The Structures and Materials Division at the NASA Glenn Research Center (GRC) heavily uses the on-site XRD lab to characterize advanced metal alloys, ceramics, and polymers. One of the ...]]></description><pubDate>Mon, 20 May 2013 00:00:00 GMT</pubDate><guid>http://ntrs.nasa.gov/search.jsp?R=20130013469</guid></item><item><title>Buckling Testing and Analysis of Honeycomb Sandwich Panel Arc Segments of a Full-Scale Fairing Barrel Part 1: 8-Ply In-Autoclave Facesheets (Part 1. 8-Ply In-Autoclave Facesheets.)</title><link>http://ntrs.nasa.gov/search.jsp?R=20130013468</link><description><![CDATA[Abstract: Four honeycomb sandwich panels, representing 1/16th arc segments of a 10-m diameter barrel section of the heavy lift launch vehicle, were manufactured under the NASA Composites for Exploration program and the NASA Space Launch Systems program. Two configurations were chosen for the panels: 6-ply facesheets with 1.125 in. honeycomb core and 8-ply facesheets with 1.000 in. honeycomb core. Additionally, two separate carbon fiber/epoxy material systems were chosen for the facesheets: inautoclave ...]]></description><pubDate>Mon, 20 May 2013 00:00:00 GMT</pubDate><guid>http://ntrs.nasa.gov/search.jsp?R=20130013468</guid></item></channel></rss>
