On sums of Rudin-Shapiro coefficients II

Let {a(n)} be the Rudin-Shapiro sequence, and let s(n) = ∑a(k) and t(n) = ∑(-1)k a(k). In this paper we show that the sequences {s(n)/√n} and {t(n)/√n} do not have cumulative distribution functions, but do have logarithmic distribution functions (given by a specific Lebesgue integral) at each point of the respective intervals [√3/5, √6] and [0, √3]. The functions a(x) and s(x) are also defined for real x ≥ 0, and the function [s(x) – a(x)]/√x is shown to have a Fourier expansion whose coefficients are related to the poles of the Dirichlet series ∑a(n)/n, where Re τ > ½

Detailed modal testing of a solid rocket motor using a portable test system

Modern analytical techniques have expended the ability to evaluate solid rocket motors used in launch vehicles. As more detailed models of solid rocket motors were developed, testing methods were required to verify the models. Experimental modal analysis (modal testing) of space structures and launch vehicles has been a requirement for model validation for many years. However, previous testing of solid rocket motors has not typically involved dynamic modal testing of full scale motors for verification of solid propellant or system assembly properties. Innovative approaches to the testing of solid rocket motors were developed and modal testing of a full scale, two segment Titan 34D Solid Rocket Motor (SRM) was performed to validate detailed computer modeling. Special modifications were made to convert an existing facility into a temporary modal test facility which would accommodate the test article. The assembly of conventional data acquisition equipment into a multiple channel count portable system has made modal testing in the field feasible. Special purpose hydraulic exciters were configured to apply the dynamic driving forces required. All instrumentation and data collection equipment were installed at the test site for the duration of the test program and removed upon completion. Conversion of an existing test facility into a temporary modal test facility, and use of a multiple channel count portable test data acquisition system allowed all test objectives to be met and resulted in validation of the computer model in a minimum time

Teaching audience analysis to the technical student

Teaching audience analysis, as practiced in a technical writing course for engineering students, is discussed. Audience analysis is described as the task of defining the audience for a particular piece of writing and determining those characteristics of the audience which constrain the writer and effect reception of the message. A mature technical writing style that shows the tension produced when a text is written to be read and understood is considered in terms of audience analysis. Techniques include: (1) conveying to students the concept that a reader with certain expectations exist, (2) team teaching to preserve the context of a given technical discipline, and (3) assigning a technical report that addresses a variety of readers, thus establishing the complexity of audience oriented writing

Women without Men: Hemingway\u27s Female Characters

Ernest Hemingway wrote four major novels and dozens of short stories during his long career as one of America\u27s preeminent twentieth century writers. Both during his lifetime and after his death, critics have written extensively about his work, analyzing it, interpreting it, and evaluating it. Perhaps the most debated aspect of the canon is Hemingway\u27s treatment of female characters. In the past, critics tended to arrange Hemingway\u27s heroines into categories, frequently dividing them into two groups: the bitches and the goddesses. More recent criticism eschews the restrictions of categories, focusing on the women as individuals and attempting to explain their behavior by analyzing their motivation. An examination of Hemingway\u27s life and some of his work leads to a better understanding of his depiction of women. By looking at the heroines of three novels--The Sun Also Rises, A Farewell to Arms, and For Whom the Bell Tolls--and four short stories-- Up In Michigan, The Short, Happy Life of Francis Macomber, The Snows of Kilimanjaro, and Hills Like White Elephants --we can gain insight into Hemingway\u27s female characters and into the author\u27s attitude toward them. In the end, it is quite possible to see Hemingway\u27s female characters in the same light as we look at his male characters--as developing human beings crossing the plain and moving through the valley on their way to the mountain top, where those who adhere to Hemingway\u27s code live out their lives

A Hope That’s Not So Hollow: How the Supreme Court’s Decisions in Windsor and Perry Alter the Political Environment in Which Marriage Equality Activism Operates

This thesis looks at the state of marriage equality activism in the wake of the Supreme Court’s June 26, 2013 decisions in United States v. Windsor and Hollingsworth v. Perry. Some scholars, such as Gerald Rosenberg, argue that Supreme Court decisions can never affect “significant social change,” either directly or indirectly, while others argue that such decisions can be hugely important in directly affecting policy. My focus is on how activist organizations, which have a substantial track record of directly affecting policy, are influenced by changes to the political environment stemming from major Court decisions regarding social issues. After examining how past litigative efforts such as Baehr v. Lewin and Goodridge v. Department of Public Health have affected the LGBT rights movement, and marriage equality activism specifically, I discuss how organizational strategies have changed minimally, but the political environment in which marriage equality activism is operating has shifted quite a bit, especially in terms of framing and legal precedent. I conclude that Court decisions can indeed have a significant impact on social change by affecting the way in which it is possible for activists on both sides of the issue to shape and deliver their message to the general public, legislators, and courts in future litigative efforts

Fabrication techniques developed for small- diameter, thin-wall tungsten and tungsten alloy tubing

Report describes methods for the fabrication of tungsten and tungsten alloys into small-diameter, thin-wall tubing of nuclear quality. The tungsten, or tungsten alloy tube blanks are produced by double extrusion. Plug-drawing has emerged as an excellent secondary fabrication technique for the reduction of the overall tube dimensions

Inheritance of Pitted Ear through Six Generations

Several papers have appeared in recent years on the inheritance of ear pit (Fistula auris congenita), but despite the accumulation of data over a long period of years, the problem of the mechanism involved in hereditary transmission of ear pit is not completely satisfactory

Modal survey of the space shuttle solid rocket motor using multiple input methods

The ability to accurately characterize propellant in a finite element model is a concern of engineers tasked with studying the dynamic response of the Space Shuttle Solid Rocket Motor (SRM). THe uncertainties arising from propellant characterization through specimem testing led to the decision to perform a model survey and model correlation of a single segment of the Shuttle SRM. Multiple input methods were used to excite and define case/propellant modes of both an inert segment and, later, a live propellant segment. These tests were successful at defining highly damped, flexible modes, several pairs of which occured with frequency spacing of less than two percent

Model Validation of an RSRM Transporter Through Full-scale Operational and Modal Testing

The Reusable Solid Rocket Motor (RSRM) segments, which are part of the current Space Shuttle system and will provide the first stage of the Ares launch vehicle, must be transported from their manufacturing facility in Promontory, Utah, to a railhead in Corinne, Utah. This approximately 25-mile trip on secondary paved roads is accomplished using a special transporter system which lifts and conveys each individual segment. ATK Launch Systems (ATK) has recently obtained a new set of these transporters from Scheuerle, a company in Germany. The transporter is a 96-wheel, dual tractor vehicle that supports the payload via a hydraulic suspension. Since this system is a different design than was previously used, computer modeling with validation via test is required to ensure that the environment to which the segment is exposed is not too severe for this space-critical hardware. Accurate prediction of the loads imparted to the rocket motor is essential in order to prevent damage to the segment. To develop and validate a finite element model capable of such accurate predictions, ATA Engineering, Inc., teamed with ATK to perform a modal survey of the transport system, including a forward RSRM segment. A set of electrodynamic shakers was placed around the transporter at locations capable of exciting the transporter vehicle dynamics. Forces from the shakers with varying phase combinations were applied using sinusoidal sweep excitation. The relative phase of the shaker forcing functions was adjusted to match the shape characteristics of each of several target modes, thereby customizing each sweep run for exciting a particular mode. The resulting frequency response functions (FRF) from this series of sine sweeps allowed identification of all target modes and other higher-order modes, allowing good comparison to the finite element model. Furthermore, the survey-derived modal frequencies were correlated with peak frequencies observed during road-going operating tests. This correlation enabled verification of the most significant modes contributing to real-world loading of the motor segment under transport. After traditional model updating, dynamic simulation of the transportation environment was compared to the measured operating data to provided further validation of the analysis model. KEYWORDS Validation, correlation, modal test, rocket motor, transporte

Primality Testing with Artin Symbols

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