3,443 research outputs found
Exploratory wind-tunnel investigation of deployable flexible ventral fins for use as an emergency spin-recovery device
Spin tunnel tests to determine effectiveness of deployable, flexible ventral fins for spin recovery device on fighter aircraf
Low-speed dynamic model investigation of Apollo command module configurations in the Langley spin tunnel
Dynamic stability of Apollo command module with and without drogue parachutes at low subsonic speeds in spin tunne
Deposit of Silica in Acer saccharinum L.
Report of a small quartz pebble found imbedded in the wood of Acer saccharinum L
Radio-controlled model design and testing techniques for stall/spin evaluation of general-aviation aircraft
A relatively inexpensive radio-controlled model stall/spin test technique was developed. Operational experiences using the technique are presented. A discussion of model construction techniques, spin-recovery parachute system, data recording system, and movie camera tracking system is included. Also discussed are a method of measuring moments of inertia, scaling of engine thrust, cost and time required to conduct a program, and examples of the results obtained from the flight tests
Self-Parasitism in Achlya racemosa Hildb.
In cultures of Achlya racemosa Hildb. oospores in the oogonium were completely absorbed by hyphae arising from antheridia or from the wall dividing the oogonium and stipe
Deployment techniques of a parawing used as a recovery device for manned reentry vehicles and large boosters
Spin-Tunnel Investigation of the Spinning Characteristics of Typical Single-Engine General Aviation Airplane Designs. 1. Low-Wing Model A: Effects of Tail Configurations
The effects of tail design on spin and recovery were investigated in a spin tunnel. A 1/11-scale model of a research airplane which represents a typical low-wing, single engine, light general aviation airplane was used. A tail design criterion for satisfactory spin recovery for light airplanes was evaluated. The effects of other geometric design features on the spin and recovery characteristics were also determined. Results indicate that the existing tail design criterion for light airplanes, which uses the tail damping power factor as a parameter, cannot be used to predict spin-recovery characteristics
Spin-tunnel investigation of the spinning characteristics of typical single-engine general aviation airplane designs. 2: Low-wing model A; tail parachute diameter and canopy distance for emergency spin recovery
A spin tunnel study is reported on a scale model of a research airplane typical of low-wing, single-engine, light general aviation airplanes to determine the tail parachute diameter and canopy distance (riser length plus suspension-line length) required for energency spin recovery. Nine tail configurations were tested, resulting in a wide range of developed spin conditions, including steep spins and flat spins. The results indicate that the full-scale parachute diameter required for satisfactory recovery from the most critical conditions investigated is about 3.2 m and that the canopy distance, which was found to be critical for flat spins, should be between 4.6 and 6.1 m
The Role of Supervision in Youth Work: Perceptions of Students Preparing to be Youth Workers
Working with youth involves mentoring and guiding youth through development of their physical, emotional, intellectual, and social skills, as they become adults. One would assume a great responsibility of working with young people comes with extensive training in one particular field; however, this is not always the case (Barcelona, Hurd, & Bruggeman, 2011). The purpose of this study was to examine the perceptions expressed by undergraduate students preparing for a career in youth work regarding their knowledge and competence of supervision in a park and recreation setting. It was found in the pre- and post- surveys that future youth workers believe they are confident in supervision. There was statistically significant difference in confidence levels and abilities to take a supervisory role. In addition, students indicated significant growth in their confidence and ability to properly follow risk management procedures. Furthermore, three themes emerged: first, future youth workers welcome the challenge and responsibility of supervision duties; second, risk management is important to future youth workers; and third, future youth workers want to engage in supervision responsibilities and practices. The findings of the study suggest future youth workers may not realize the gravity of their decisions to combat issues of victimization among youth participants or may not fully understand what it looks like to be negligent as it relates to supervision responsibilities
Administering Model-based Patient-specific Supplemental Oxygen Therapy
Purpose: The oxyhemoglobin dissociation curve describes the relationship between the partial pressure of oxygen and the percent of hemoglobin saturated with oxygen and varies with chemical and physical factors that differ for every patient. If variability could be determined, patient specific oxygen therapy could be administered. We have developed a procedure for characterizing variations in the oxygen dissociation curve. The purpose of this study was to validate this procedure in surgical patients. Methods: The procedure uses an automated system to alter oxygen therapy and Hill\u27s equation to fit measurements. Once measurements are gathered, the procedure uses an iterative least-squares method to determine best-fit parameters for the Hill equation. The procedure was performed on surgical patients after which model fit was assessed. Results: 39 patients participated in this study. Using patient-specific parameter values increases correlation when compared to standard values. The procedure improved the model fit of patient saturation values significantly in 19 patients. Conclusions: This paper has demonstrated a procedure for determining patient specific pulse oximeter response. This procedure determined best-fit parameters resulting in a significantly improved fit when compared to standard values. These best-fit parameters increased the coefficient of determination R2 in all cases
- …