The part-through surface crack in an elastic plate

Tensile stretching and bending of elastic plate containing surface crac

Tip vortex computer code SRATIP. User's guide

This User's Guide applies to the three dimensional viscous flow forward marching analysis, PEPSIG, as used for the calculation of the helicopter tip vortex flow field. The guide presents a discussion of the program flow and subroutines, as well as a list of sample input and output

Sources of sport confidence, imagery type and performance among competitive athletes: The mediating role of sports confidence

Aim: This study explored the mediating role of sport confidence upon (1) sources of sport confidence-performance relationship and (2) imagery-performance relationship. Methods: Participants were 157 competitive athletes who completed state measures of confidence level/sources, imagery type and performance within one hour after competition. Results: Among the current sample, confirmatory factor analysis revealed appropriate support for the nine-factor SSCQ and the five-factor SIQ. Mediational analysis revealed that sport confidence had a mediating influence upon the achievement source of confidence-performance relationship. In addition, both cognitive and motivational imagery types were found to be important sources of confidence, as sport confidence mediated imagery type-performance relationship. Conclusion: Findings indicated that athletes who construed confidence from their own achievements and report multiple images on a more frequent basis are likely to benefit from enhanced levels of state sport confidence and subsequent performance

Sources of sport confidence, imagery type and performance among competitive athletes: The mediating role of sports confidence

Aim: This study explored the mediating role of sport confidence upon (1) sources of sport confidence-performance relationship and (2) imagery-performance relationship. Methods: Participants were 157 competitive athletes who completed state measures of confidence level/sources, imagery type and performance within one hour after competition. Results: Among the current sample, confirmatory factor analysis revealed appropriate support for the nine-factor SSCQ and the five-factor SIQ. Mediational analysis revealed that sport confidence had a mediating influence upon the achievement source of confidence-performance relationship. In addition, both cognitive and motivational imagery types were found to be important sources of confidence, as sport confidence mediated imagery type-performance relationship. Conclusion: Findings indicated that athletes who construed confidence from their own achievements and report multiple images on a more frequent basis are likely to benefit from enhanced levels of state sport confidence and subsequent performance

The diocotron instability in a quasi-toroidal geometry

Slipstream instability of low density electron beams in crossed electric and magnetic field

A three-dimensional viscous flow analysis for the helicopter tip vortex generation problem

The tip vortex flow field occurring in the vicinity of the tip region of a a helicopter rotor blade is a very complicated three-dimensional, viscous flow phenomenon. The details of the flow in the tip region can have a major effect in determining the generated rotor noise and can significantly affect the performance and dynamic loading of the rotor blade. The three-dimensional viscous subsonic tip vortex generation processes is investigated by a numerical procedure which allows spatial forward-marching integration, utilizing flow approximations from the velocity-decomposition approach of Briley and McDonald. The approach has been applied to compute the laminar and turbulent tip vortex flows for a constant thickness slab airfoil with a square tip, a constant thickness slab airfoil with a half round tip and a NACA 0012 airfoil with a half round tip. The basic mechanism of the tip vortex generation process as well as the prediction of vortex appearance, strength and secondary flow shown by the calculations are in qualitative agreement with experimental results

A program to evaluate a control system based on feedback of aerodynamic pressure differentials, part 1

The use of pressure differentials in a flight control system was evaluated. The pressure profile around the test surface was determined using two techniques: (1) windtunnel data (actual); and (2) NASA/Langley Single Element Airfoil Computer Program (theoretical). The system designed to evaluate the concept of using pressure differentials is composed of a sensor drive and power amplifiers, actuator, position potentiometer, and a control surface. The characteristics (both desired and actual) of the system and each individual component were analyzed. The desired characteristics of the system as a whole are given. The flight control system developed, the testing procedures and data reduction methods used, and theoretical frequency response analysis are described

Development of advanced digital techniques for data acquisition processing and communication Interim scientific report

Image correlation and computerized simulation applied to data acquisition and imaging technique