An engineering study of hybrid adaptation of wind tunnel walls for three-dimensional testing

Solid wall tunnels having only upper and lower walls flexing are described. An algorithm for selecting the wall contours for both 2 and 3 dimensional wall flexure is presented and numerical experiments are used to validate its applicability to the general test case of 3 dimensional lifting aircraft models in rectangular cross section wind tunnels. The method requires an initial approximate representation of the model flow field at a given lift with wallls absent. The numerical methods utilized are derived by use of Green's source solutions obtained using the method of images; first order linearized flow theory is employed with Prandtl-Glauert compressibility transformations. Equations are derived for the flexed shape of a simple constant thickness plate wall under the influence of a finite number of jacks in an axial row along the plate centerline. The Green's source methods are developed to provide estimations of residual flow distortion (interferences) with measured wall pressures and wall flow inclinations as inputs

Relationally Managing Weight Loss

Previous research emphasizes the link between social support and weight loss. However, scholarship has failed to explore how family members enact support during an individual\u27s weight loss attempt and how participation in a weight loss program impacts family communication about dietary choices. This project examines how family members enact support for individuals in a weight loss program and how as a result of participating in a weight loss program family members renegotiate relational norms and rules regarding dietary behaviors. Thirteen individuals (n= 13), eleven (11) females and two (2) males enrolled in a medically supervised weight management program journaled about their experiences over a twelve (12) week period. Analysis reveals the dual nature of social support, how families and relational partners renegotiate rules and norms regarding dietary behavior and how relational partners impact dietary choices. Theoretical and practical implications for interpersonal, family, and health communication are discussed as well as implications for weight management program practitioners. The thesis concludes with recommendations for future research

Situating the Study of Messages about Non-Heterosexual Sexual Orientation in Everyday Ordinary Interactions: A Call for Paradigm Change

This study explores the motivations that may orient an individual to another\u27 s sexual orientation. Extant literature has traditionally focused on the ways in which individuals detect or recognize another\u27s sexual orientation, but has failed to explore the communicative strategies individuals routinely engage in and the reasons he or she may be interested in another\u27 s sexual orientation. As such, this study fits nicely into the interpersonal and intercultural communication literatures that concern themselves with the social construction of identity, which is an ongoing interactional task to which conversationalists orient. The data for this study was collected during the fall of 2012 from the self-report responses from a sample of undergraduate and graduate students (N=574) enrolled in on-campus courses at a mid-sized Midwestern university and from in-depth interviews conducted with five participants. Thus, the goal of this exploratory study is to investigate the ways in which individuals understand behaviors attributed to differing sexual orientations and the reasons why sexual orientation becomes relevant in ordinary everyday social interactions. Furthermore, this study offers insight into how assuming heterosexuality affects the ways in which non-heterosexuals communicate during their everyday interactions

NACA Investigation of a Jet-Propulsion System Applicable to Flight

Following a brief history of the NACA investigation of jet-propulsion, a discussion is given of the general investigation and analyses leading to the construction of the jet-propulsion ground-test mock-up. The results of burning experiments and of test measurements designed to allow quantitative flight-performance predictions of the system are presented and correlated with calculations. These calculations are then used to determine the performance of the system on the ground and in the air at various speeds and altitudes under various burning conditions. The application of the system to an experimental airplane is described and some performance predictions for this airplane are made. It was found that the main fire could be restricted to an intense, small, and short annular blue flame burning steadily and under control in the intended combustion space. With these readily obtainable combustion conditions, the combustion chamber the nozzle walls and the surrounding structure could be maintained at normal temperatures. The system investigated was found to be capable of burning one-half the intake air up the fuel rates of 3 pounds per second. Calculations were shown to agree well with experiment. It was concluded that the basic features of the jet-propulsion system investigation in the ground-test mock-up were sufficiently developed to be considered applicable to flight installation. Calculations indicated that an airplane utilizing this jet-propulsion system would have unusual capabilities in the high-speed range above the speeds of conventional aircraft and would, in addition, have moderately long cruising ranges if only the engine were used

Theoretical lift and drag of thin triangular wings at supersonic speeds

A method is derived for calculating the lift and the drag due to lift of point-forward triangular wings and a restricted series of sweptback wings at supersonic speeds. The elementary or "supersonic sources" solution of the linearized equation of motion is used to find the potential function of a line of doublets. The flow about the triangular flat plate is then obtained by a surface distribution of these doublet lines. The lift-curve slope of triangular wings is found to be a function of the ratio of the tangent of the apex angle to the tangent of the Mach angle. As the apex angle approaches and becomes greater than the Mach angle, the lift coefficient of the triangular wing becomes equal to that of a two-dimensional supersonic airfoil at the same Mach number. The drag coefficient due to lift of triangular wings with leading edges well behind the Mach cone is shown to be close to that of elliptically loaded wings of the same aspect ratio in subsonic flight. The resultant force on wings with leading edges outside the Mach cone, however, is shown to act normal to the surfaces and thus an induced drag equal to the lift times the angle of attack is obtained

The reversibility theorem for thin airfoils in subsonic and supersonic flow

A method introduced by Munk is extended to prove that the light-curve slope of thin wings in either subsonic flow or supersonic flow is the same when the direction of flight of the wing is reversed. It is also shown that the wing reversal does not change the thickness drag, damping-in-roll parameter or the damping-in-pitch parameter

Development and Validation of the Public Speaking Attitude Scale: A Theoretical Approach to Assess Student Performance in Public Speaking Courses in Higher Education

Although anxiety is an important component of individuals’ relationship with public speaking, it only represents a portion of the story. Specifically, understanding attitudes toward public speaking can help instructors develop improved methods for teaching and assessing student performance in speech classes, and on oral communication-based university-level learning outcomes. This study addresses our lack of understanding of attitudes towards public speaking by collecting and examining data from 1,112 college students to develop a Public Speaking Attitude Scale and examine the scale’s ability to predict students’ intent to leverage skills learned in introductory speech classes in their future endeavors. Initial item development and validation are described, and the scale is compared against existing measures to determine which scale accounts for more variance in students’ intent to leverage public speaking skills. Findings suggest that Public Speaking Attitude accounts for significantly more variance than public speaking anxiety and shyness in a student’s intent to leverage skills learned in the basic speech course. Implications and avenues for future research are discussed

NACA Investigation of a Jet-Propulsion System Applicable to Flight

Following a brief history of the NACA investigation of jet propulsion, a discussion is given of the general investigation and analysis leading to the construction of the jet-propulsion ground-test mock-up. The results of burning experiments and of test measurements designed to allow quantitative flight performance predictions of the system are presented and correlated with calculations. These calculations are then used to determine the performance of the system on the ground and in the air at various speeds and altitudes under various burning conditions. The application of the system to an experimental airplane is described and some performance predictions for this airplane are made