Advanced oxide dispersion strengthened sheet alloys for improved combustor durability

Burner design modifications that will take advantage of the improved creep and cyclic oxidation resistance of oxide dispersion strengthened (ODS) alloys while accommodating the reduced fatigue properties of these materials were evaluated based on preliminary analysis and life predictions, on construction and repair feasibility, and on maintenance and direct operating costs. Two designs - the film cooled, segmented louver and the transpiration cooled, segmented twin Wall - were selected for low cycle fatigue (LCF) component testing. Detailed thermal and structural analysis of these designs established the strain range and temprature at critical locations resulting in predicted lives of 10,000 cycles for MA 956 alloy. The ODs alloys, MA 956 and HDA 8077, demonstrated a 167 C (300 F) temperature advantage over Hastelloy X alloy in creep strength and oxidation resistance. The MA 956 alloy was selected for mechanical property and component test evaluations. The MA 956 alloy was superior to Hastelloy X in LCF component testing of the film cooled, segmented louver design

Vibroacoustic study of the NASA Goddard Space Flight Center OSS-1 payload

A comparative evaluation of shuttle liftoff and ground test random response data obtained from the Office of Space Science-1 (OSS-1) pallet payload flown in the cargo bay of STS-3 is presented. The study was initiated to evaluate the possibility that the payload flight vibration response can exceed that occurred during ground test when the ground test acoustic excitation is normalized to the flight acoustic environment. In addition, the analytically derived response from the Vibroacoustic Payload Environment Prediction System (VAPEPS) is compared with OSS-1 ground test results

A procedure for combining acoustically induced and mechanically induced loads (first passage failure design criterion)

The combined load statistics are developed by taking the acoustically induced load to be a random population, assumed to be stationary. Each element of this ensemble of acoustically induced loads is assumed to have the same power spectral density (PSD), obtained previously from a random response analysis employing the given acoustic field in the STS cargo bay as a stationary random excitation. The mechanically induced load is treated as either (1) a known deterministic transient, or (2) a nonstationary random variable of known first and second statistical moments which vary with time. A method is then shown for determining the probability that the combined load would, at any time, have a value equal to or less than a certain level. Having obtained a statistical representation of how the acoustic and mechanical loads are expected to combine, an analytical approximation for defining design levels for these loads is presented using the First Passage failure criterion

Ordinary Magic : On Peter Flemming's Instrumentation

Text commissioned by Skol in repsonse to Peter Flemming's exhibition Instrumentation, as part of the 2012 International Digital Arts Biennial

Jean-Paul Sartre: The Bad Faith of Empire

Henricks shows Sartre\u27s concept of bad faith as a considerable influence several theologians\u27 criticism of empire. In order to explain bad faith, Henricks first elucidates Sartre\u27s concepts of being-in-itself and being-for-itself. While being-in-itself implies on object that simply is what it is and cannot become more than its current identity, being-for-itself has the capacity to change and transcend its current identity. Humans, Henricks points out, are beings-for-themselves but they also contain qualities associated with beings-in-themselves. This duality of humanity is of the utmost importance to respect. Bad faith is a lie to oneself that has destabilizing results. Bad Faith can also occur outside of oneself towards others in the form of objectification or by shirking responsibility for actions. This links the theory of bad faith to imperialism a social reality for which many try to avoid responsibility. The theologian Kelly Brown Douglas sees bad faith occurring when people are not treated as though they have being-for-itself status. Henricks also uses the work of Cynthia Moe-Lobeda to condemn imperialism using bad faith. Moe-Lobeda says bad faith is tied to transnational companies gaining so much power and money that they can make it impossible for Christians to act in accordance with the Gospel. No matter their action, Christians will always play into the hands of the more powerful. Mark Lewis Taylor uses the concept of bad faith in his explanation of the way that liberalism champions liberty and justice, but only for a select number of people. Henricks shows that theologians and Christian social ethicists frequently make use of Sartre\u27s theory of bad faith. She demonstrates that his lens can be revealing when looking at the problem of empire and that his writings have greatly influenced some great Christian writings on the subject

No Taxation Without Discrimination: The Racial Politics of American Property Taxes

No longer is it acceptable to rationalize racial hierarchy in explicit terms. Today’s ideology substitutes these explanations for cultural ones that diminish racial oppression. Though recent studies uncover the slippery, covert, and seemingly nonracial discourse of colorblindness, claims of ideological progression are offered without empirical verification. Examining debate surrounding the three-fifths clause of the U.S Constitution, I complete a “historical ethnographic content analysis” that transplants colorblind ideology into historical soil some presume it does not belong. The data derive from “A Century of Lawmaking for a New Nation” and consist of 1,493 pages of congressional record. My findings reveal how colorblindness captured in phrases like “I’m not racist, but…” have historical parallels in “I’m principled against slavery, but….” This observation merits more attention because it shows how contemporary ideology was not created out of whole cloth in post-1960s America. Contrary to approaches that contend racism is reflective of other social forces, comprised by a dominant ideology, and follows historically discrete categories, I advance an alternative viewpoint: a “racial ideology complex.” It defines racism as possessing a significant degree of autonomy from the political economy, consisting of multiple, differentiated ideological currents, and following a continuous, more connected path across time