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The Measurement of Pressure Altitude on Aircraft

Description: Note presenting a determination of the accuracy with which pressure altitude can be measured by calculation of the errors in the measuring system, errors arising from operation of the system, and variations in atmospheric pressure. Some possibilities for reducing errors in the categories of altimeter-scale error, static-pressure error, atmospheric-reference error, flight technical error, friction error, and service error are provided.
Date: October 1957
Creator: Gracey, William
Partner: UNT Libraries Government Documents Department

Method Rendering It Possible, in Testing Airplane Wing Models at the Eiffel Laboratory, to Obtain Comparable Polars, Whether the Supports Are Attached to the Upper or Lower Side of Model

Description: Report presenting an examination of the errors that result from testing an aircraft model and applying the results to full-sized airplanes. An investigation is carried out to determine how to obtain comparable polars regardless of whether the supports are attached to the upper or lower side of the model.
Date: November 1922
Creator: Eiffel, G.
Partner: UNT Libraries Government Documents Department

Trend to Be Given Aerodynamical Research and Experiment

Description: The causes of error in experiments conducted in wind tunnel tests are given and the value of in-flight tests are promoted. The four main causes explored include neglect of the laws of dynamic similitude, interference between the support and the model, nature of the air stream, and the influence of the walls of the tunnel.
Date: June 1923
Creator: Lèpere, M.
Partner: UNT Libraries Government Documents Department

Measurement of Static Pressure on Aircraft

Description: "Existing data on the errors involved in the measurement of static pressure by means of static-pressure tubes and fuselage vents are presented. The errors associated with the various design features of static-pressure tubes are discussed for the condition of zero angle of attack and for the case where the tube is inclined to flow. Errors which result from variations in the configuration of static-pressure vents are also presented" (p. 645).
Date: December 17, 1956
Creator: Gracey, William
Partner: UNT Libraries Government Documents Department

An Investigation of Aircraft Heaters 35: Thermocouple Conduction Error Observed in Measuring Surface Temperatures

Description: Note presenting experimental results that verify an analysis of errors occurring when thermocouples are used to measure the temperature of surfaces exposed at temperatures different from that of the surface. The data indicate that the electrical insulation of the wires is not effective in reducing the errors involved when the thermocouples are placed normal to the surface and exposed to the ambient fluids.
Date: July 1951
Creator: Boelter, L. M. K. & Lockhart, R. W.
Partner: UNT Libraries Government Documents Department

An Application of Spencer's Method to the Stieltjes and Hamburger Moment Problems

Description: Given the moments of a function it is often desirable to obtain a numerical approximation of the function. A method for estimating the solutions of the Stieltjes and Hamburger moment problems is developed. Calculations indicate that the method is both feasible and accurate. (auth)
Date: July 1, 1959
Creator: Guilinger, W. H.
Partner: UNT Libraries Government Documents Department

A Multiple Bridge for Elimination of Contact-Resistance Errors in Resistance Strain-Gauge Measurements

Description: Note presenting a multiple-bridge circuit that eliminates contact-resistance errors of the first order between the arms of the ordinary Wheatstone bridge. The circuit is applied to the elimination of the effects of contact-resistance variations that may occur in resistance strain-gage measurements made through switch contacts or slip rings. The general theory is derived and correct circuits and constructions are described.
Date: March 1946
Creator: Warshawsky, Isidore
Partner: UNT Libraries Government Documents Department

Analysis of Solar Two Heliostat Tracking Error Sources

Description: This paper explores the geometrical errors that reduce heliostat tracking accuracy at Solar Two. The basic heliostat control architecture is described. Then, the three dominant error sources are described and their effect on heliostat tracking is visually illustrated. The strategy currently used to minimize, but not truly correct, these error sources is also shown. Finally, a novel approach to minimizing error is presented.
Date: January 28, 1999
Creator: Jones, S.A. & Stone, K.W.
Partner: UNT Libraries Government Documents Department

Shakespeare's The Comedy of Errors Revised for High School and College Production

Description: This revision of Shakespeare's The Comedy of Errors is in no way intended to take the place of a serious study of the original work. It is, rather, a revision to make the play a suitable stage vehicle for high school and college drama groups which would otherwise shun it because of the language difficulties involved.
Date: August 1964
Creator: Hawkins, W. Neil
Partner: UNT Libraries

Static-pressure error calibrations for nose-boom airspeed installations of 17 airplanes

Description: Report presenting a flight investigation to determine the static-pressure errors for nose-boom airspeed installations of 17 airplanes. Both research-type and service-type aircraft are covered in the investigation. Results indicated that the magnitude of static-pressure errors for the airspeed installations of all the airplanes is shown to vary with airplane geometric characteristics that include nose-boom length, fuselage diameter, and nose fineness ratio.
Date: March 13, 1957
Creator: Larson, Terry J.; Stillwell, Wendell H. & Armistead, Katharine H.
Partner: UNT Libraries Government Documents Department

Construction of an Extended Nuclidic Mass Table

Description: A parabolic systematics approach was used to construct an extended mass table with very small deviations between the calculated and known masses. The masses were obtained from a formula parabolic in 2 after inclusion of the necessary considerations. For 763 masses, the standard deviation was 0.35 Mev, and the largest deviation was 2 Mev. (D.C.W.)
Date: July 1, 1963
Creator: Hillman, M.
Partner: UNT Libraries Government Documents Department

The Crosscorrelation Method of Measuring System Dynamic Response

Description: The basic relations of the crosscorrelation method are presented; and variations of the method for dealing with practical cases for which the idealized relations are inaccurate due to finite experiment length, finite bandwidth of the input signal, and uncorrelated noise in the system response signal are discussed and demonstrated. (D.C.W.)
Date: November 1, 1963
Creator: Balcomb, J. D.
Partner: UNT Libraries Government Documents Department

Flight determination of the effects of rudder-pedal-force characteristics on the aiming error in azimuth of a conventional fighter airplane

Description: Report presenting flight tests to study the effect on aiming error in azimuth of a change in the rudder-pedal-force characteristics of a conventional fighter airplane equipped with an illuminated fixed gunsight. The effect of the modification on the mean azimuth tracking errors was insignificant, but pilots noted that the modified rudder made it tiring to fly the airplane for any length of time.
Date: July 5, 1950
Creator: Winograd, Lee & Van Dyke, Rudolph D., Jr.
Partner: UNT Libraries Government Documents Department


Description: A general numerical procedure, called the discrete S/sub n/ method, for solving the neutron transport equation is described. The main topics relate to the derivation of suitable difference equations, and to the problem of solving these, while maintaining generality, accuracy, and reasonable computing speed. A few comparisons with other methods are made. (auth)
Date: May 16, 1959
Creator: Carlson, B.
Partner: UNT Libraries Government Documents Department

Neutron beam irradiation study of workload dependence of SER in a microprocessor

Description: It is known that workloads are an important factor in soft error rates (SER), but it is proving difficult to find differentiating workloads for microprocessors. We have performed neutron beam irradiation studies of a commercial microprocessor under a wide variety of workload conditions from idle, performing no operations, to very busy workloads resembling real HPC, graphics, and business applications. There is evidence that the mean times to first indication of failure, MTFIF defined in Section II, may be different for some of the applications.
Date: January 1, 2009
Creator: Michalak, Sarah E; Graves, Todd L; Hong, Ted; Ackaret, Jerry; Sonny, Rao; Subhasish, Mitra et al.
Partner: UNT Libraries Government Documents Department

Error Sources in the ETA Energy Analyzer Measurement

Description: At present the ETA beam energy as measured by the ETA energy analyzer and the DARHT spectrometer differ by {approx}12%. This discrepancy is due to two sources, an overestimate of the effective length of the ETA energy analyzer bending-field, and data reduction methods that are not valid. The discrepancy can be eliminated if we return to the original process of measuring the angular deflection of the beam and use a value of 43.2cm for the effective length of the axial field profile.
Date: December 13, 2004
Creator: Nexsen, W E
Partner: UNT Libraries Government Documents Department

Phase Errors and the Capture Effect

Description: This slide-show presents analysis of spectrograms and the phase error of filtered noise in a signal. When the filtered noise is smaller than the signal amplitude, the phase error can never exceed 90{deg}, so the average phase error over many cycles is zero: this is called the capture effect because the largest signal captures the phase and frequency determination.
Date: November 1, 2011
Creator: Blair, J., and Machorro, E.
Partner: UNT Libraries Government Documents Department