34,330 Matching Results

Search Results

Advanced search parameters have been applied.

Evaluation of Gust and Draft Velocities from Flights of P-61c Airplanes within Thunderstorms 2 - July 9, 1946 to July 11, 1946 at Orlando, Florida

Description: "The results obtained from an evaluation for gust and draft velocities of acceleration and airspeed-altitude records taken by NACA recording instruments installed in P-61c airplanes participating in thunderstorm flights 6, 7, and 8 of July 9, 1946, July 10, 1946, and July 11, 1946, respectively, are presented herein. These data are summarized in tables I and II. In accordance with a recent discussion with a member of the U.S. Weather Bureau staff, the tabulated results for the present flight include in addition to data of the type presented in reference 1, the initial heading of the airplane for each traverse, the pressure altitude at the start of each traverse in increments of 500 feet, and the gust gradient distance when it could be evaluated" (p. 1).
Date: September 16, 1946
Creator: Tolefson, Harold B.
Partner: UNT Libraries Government Documents Department

The Gust and Gust-Load Experience of a Twin-Engine Low-Altitude Transport Airplane in Operation on a Northern Transcontinental Route

Description: "An analysis of the gust and gust-load experience of a low-altitude transcontinental transport airplane, based on 834 hours of VGH record, is presented. The relation of gust experience to airspeed, altitude, season of the year, and flight condition is considered. An estimate of the overall gust history for the present type of operations is derived from a synthesis of the VGH data and available V-G data" (p. 1).
Date: April 1952
Creator: Press, Harry & McDougal, Robert L.
Partner: UNT Libraries Government Documents Department

An Application of the Rocket-Propelled-Model Technique to the Investigation of Low-Lift Buffeting and the Results of Preliminary Tests

Description: "The rocket-propelled-model technique has been applied to the investigation of low-lift buffeting. Results of preliminary tests show that severe buffeting, wing dropping, and normal-force changes occur almost simultaneously near zero lift over a Mach number range near 0.9 on unswept wings 12 percent thick. On unswept wings 7 percent thick, buffeting did not occur; however, mild wing dropping and normal-force changes were experienced" (p. 1).
Date: September 2, 1952
Creator: Mason, Homer P. & Gardner, William N.
Partner: UNT Libraries Government Documents Department

Base Flow of Streams on Long Island, New York

Description: Purpose and scope: The purpose of this report is to quantify the base flow of 19 continuously gaged Long Island streams during 1960-75, which includes the 1962-66 drought. These base-flow data will be used in calibrating computer models designed to predict the response of Long Island streams to hydrologic stresses such as the lowering of ground-water levels in response to large-scale sanitary sewering. The data will also be used to assess the long-term impact expected to result from storm- and sanitary-sewer systems on base flow of streams.
Date: 1982
Creator: Reynolds, Richard J.
Partner: UNT Libraries Government Documents Department

A semi-rational criterion for unsymmetrical gust loads

Description: Report presenting a discussion of the problem of establishing a rational unsymmetrical gust load criterion from available data on gust structure and it is indicated that the problem cannot be solved at the present state of knowledge without more analysis.
Date: August 1941
Creator: Rhode, Richard V. & Pearson, Henry A.
Partner: UNT Libraries Government Documents Department

Evaluation of Gust and Draft Velocities from Flights of P-61c Airplanes within Thunderstorms. 3 - July 12, 1946 to July 18, 1946 at Orlando, Florida

Description: The gust and draft velocities evaluated from acceleration and airspeed-altitude records taken by NACA instruments installed in P-61c airplanes participating in thunderstorm flights 9, 10, and 11 of July 12, 1946, July 17, 1946, and July 18, 1946, respectively, are presented in references 1 and 2 for previous flights. In accordance with a recent discussion with a member of the U.S. Weather Bureau staff, motion-picture records of the pilots' instrument panels for the present flights were inspected to note variations in the readings of a milliammeter used in conjunction with other equipment to indicate ambient air temperature. The inspection indicated that the instrument read zero throughout all traverses.
Date: November 5, 1946
Creator: Tolefson, H. B.
Partner: UNT Libraries Government Documents Department

Tests of a 45 degree sweptback-wing model in the Langley gust tunnel

Description: Report presenting a series of tests of a 45 degree sweptback-wing model with and without fuselage and an equivalent straight-wing model in the gust tunnel to provide information on some of the problems encountered in the prediction of gust loads for airplanes incorporating swept wings.
Date: February 1948
Creator: Pierce, Harold B.
Partner: UNT Libraries Government Documents Department

Tests of a gust-alleviating flap in the gust tunnel

Description: "Tests were made to determine the effectiveness of a long-period dynamically overbalanced flap in reducing airplane accelerations due to atmospheric gusts. For two gust shapes, one gust velocity, one forward velocity, and one wing loading, a series of flights was made with the flap locked and was then repeated with the flap free to operate. The records were evaluated by routine methods. The results indicate that the flap reduced the maximum acceleration increment 39 percent for a severe gust but with a representative gust shape (a sharp-edge gust), the reduction was only 3 percent" (p. 1).
Date: January 1940
Creator: Donely, Philip & Shufflebarger, C. C.
Partner: UNT Libraries Government Documents Department

Evaluation of Gust and Draft Velocities from Flights of P-61C Airplanes Within Thunderstorms August 14, 1946 to August 15, 1946 at Orlando, Florida

Description: "Tables I and II of the present paper summarize the gust and draft velocity data for thunderstorm-flights 21 and 22 of August 14, 1946 and August 15, 1946, respectively. These data were evaluated from records of NACA airspeed-altitude and acceleration recorders installed in P-61C airplanes and are of the type presented for previous flights. Table III summarizes the readings of a milliammeter which was used in conjunction with other equipment to indicate ambient-air temperature during thunderstorm surveys. These data were read from photo-observer records and include all cases in which variations of the instrument indications were noted for the present flights" (p. 1).
Date: March 19, 1947
Creator: Tolefson, H. B.
Partner: UNT Libraries Government Documents Department

Evaluation of Gust and Draft Velocities from Flights of P-61C Airplanes within Thunderstorms: August 23, 1946 to September 4, 1946 at Orlando, Florida

Description: This report presents the results obtained from gust and draft velocity measurements within thunderstorms for the period August 23, 1946 to September 4, 1946 at Orlando, Florida. These data are summarized in tables I end II and are of the type presented in reference 1 for previous flights. In several of the surveys, indications of ambient air temperature were obtained from photo-observer records. These data are summarized in table III.
Date: January 30, 1946
Creator: Tolefson, H. B.
Partner: UNT Libraries Government Documents Department

Evaluation of Gust and Draft Velocities from Flights of P-61C Airplanes Within Thunderstorms September 17, 1946 to September 18, 1946 at Orlando, Florida

Description: The results obtained from measurements of gust velocities, draft velocities, and ambient-air temperature within thunderstorms for the period September 17, 1946 to September 18, 1946 at Orlando, Fla. are presented herein. These data are summarized in tables I, II, and III, respectively, and are of the type presented in reference 1 for previous flights.
Date: March 14, 1947
Creator: Tolefson, H. B.
Partner: UNT Libraries Government Documents Department

Evaluation of Gust and Draft Velocities from Flights of P-61C Airplanes within Thunderstorms. 4 - July 19, 1946 to July 20, 1946 at Orlando, Florida

Description: "Summaries of the gust and draft velocities evaluated from acceleration and airspeed-altitude records taken by NACA instruments installed n P-61c airplanes participating in thunderstorm flights 12 and 13 of July 19, 1946, and July 20, 1946, respectively, are presented in tables I and II herein. These data are of the type presented in reference 1 for previous flights. Inspection of the motion picture records of the pilots' instrument panels for the present flights indicated that the milliameter connected to equipment for measuring ambient air temperature read zero throughout all traverses" (p. 1).
Date: November 1946
Creator: Tolefson, H. B.
Partner: UNT Libraries Government Documents Department

Evaluation of Gust and Draft Velocities from Flights of P-61C Airplanes within Thunderstorms August 21, 1946 to August 22, 1946 at Orlando, Florida

Description: Tables I and II of this report summarize the gust and draft velocity data for thunderstorm flights 25 and 26 of August 21, 1946 and August 22, 1946, respectively. These dta were evaluated from records of NACA instruments installed in P-61C airplanes and are of the type presented in reference 1 for previous flights. Table III summarizes the readings of a milliammeter which was used in conjunction with other equipment to indicate ambient air temperature during thunderstorm surveys. These data were read from motion-picture records of the instrument and include all cases in which variations in the instrument indications were noted during the present flights.
Date: 1946
Creator: Tolefson, H. B.
Partner: UNT Libraries Government Documents Department

Evaluation of Gust and Draft Velocities from Flights of P-61C Airplanes within Thunderstorms September 11, 1946 to September 16, 1946 at Orlando, Florida

Description: "The results obtained from measurements of gust velocities, draft velocities, and ambient-air temperature within thunderstorms for the period from September 11, 1946 to September 16, 1946 at Orlando, Florida are presented herein. These data are summarized in.and presented" (p. 1).
Date: March 12, 1947
Creator: Tolefson, H. B.
Partner: UNT Libraries Government Documents Department

Evaluation of Gust and Draft Velocities from Flights of P-61C Airplanes within Thunderstorms August 17, 1946 to August 19, 1946 at Orlando, Florida

Description: Results obtained from gust and draft velocity measurements within thunderstorms for the period August 17, 1946 to August 19, 1946 at Orlando, Florida are presented herein. These data are summarized in tables I and II and are of the type presented in reference 1 for previous flights. Inspection of photo-observer records taken on the present flights indicated that mo ambient-air temperature data were obtained.
Date: March 24, 1947
Creator: Tolefson, H. B.
Partner: UNT Libraries Government Documents Department

Evaluation of Gust and Draft Velocities from Flights of P-61C Airplanes within Thunderstorms July 22, 1946 to July 23, 1946 at Orlando, Florida

Description: "The results obtained from measurements of gust and draft velocities within thunderstorms for the period July 22, 1946 to July 23, 1946 at Orlando, Florida, are presented herein. These data are summarized in tables I and II, respectively, and are of the type presented in reference 1 for previous flights. Inspection of photo-observer records for the flights indicated that no data on ambient air temperature variations within thunderstorms were obtained" (p. 1).
Date: March 10, 1947
Creator: Tolefson, H. B.
Partner: UNT Libraries Government Documents Department

The Reduction of Airplane Flight Test Data to Standard Atmosphere Conditions

Description: This report was prepared for the National Advisory Committee for Aeronautics in order to supply the need of practical methods of reducing observed performance to standard conditions with a minimum of labor. The first part gives a very simple approximate method of reducing performance in climb, and is particularly adapted to work not requiring extreme accuracy. The second part gives a somewhat more elaborate and more accurate method which is well suited to general flight test reduction. The third part gives the conventional method of calibrating air-speed indicators and reducing the indicated speeds to true air speeds. An appendix gives working tables and charts for the standard atmosphere. (author).
Date: 1925
Creator: Diehl, Walter S. & Lesley, E. P.
Partner: UNT Libraries Government Documents Department

Nuclear data and measurements series: Some comments on the effects of long-range correlations in covariance matrices for nuclear data

Description: Attention is called to the considerable sensitivity of many uncertainty calculations to the magnitude of the long-ranged correlations which appear in covariance matrices. If such correlations do exist, they must be included in order to properly assess the impact of the uncertainties in the data. If, however, certain assumed long-range correlations are unrealistic, then analyses involving such correlation information are almost certain to produce misleading results. The issue is discussed in general terms, and its importance is illustrated by examples based in part on recent work from this laboratory. Some practical suggestions are offered for dealing with the matter of correlations in instances where the available information is incomplete. 23 refs., 2 figs., 1 tab.
Date: March 1, 1987
Creator: Smith, D.L.
Partner: UNT Libraries Government Documents Department

An Introduction to Data Science

Description: This book provides non-technical readers with a gentle introduction to essential concepts and activities of data science. For more technical readers, the book provides explanations and code for a range of interesting applications using the open source R language for statistical computing and graphics"--Resource home page.
Date: 2012
Creator: Stanton, Jeffrey M.
Partner: UNT Libraries

The Bureau of Mines Minerals Availability System: An Update of Information Circular 8654

Description: Report issued by the U.S. Bureau of Mines discussing the Minerals Availability System (MAS). As stated in the mission, "the mission of the Minerals Availability System is to provide current appraisals of the engineering and economic availability of non-fuel minerals for consideration in the formulation of both domestic and foreign minerals policy" (p. 3). This report includes maps, tables, and illustrations.
Date: 1982
Creator: Babitzke, Herbert R.; Barsotti, Aldo F.; Coffman, Joseph S.; Thompson, Jerrold G. & Bennett, Harold J.
Partner: UNT Libraries Government Documents Department

An Inquiry into the Inevitability of Prediction Error in Investment Portfolio Models

Description: Many mathematical programming models of the selection of investment portfolios assume that the best portfolio at any given level of risk is the portfolio having the highest level of return. The expected level of return is defined as a linear combination of the expected returns of the individual investments contained within the portfolio,and risk is defined in terms of variance of return. This study uses Monte Carlo simulation to establish that if the estimates of the future returns on potential investments are unbiased, the steady-state return on the portfolio is overestimated by the procedure used in the standard models. Under reasonable assumptions concerning the parameters of the estimates of the various returns, this bias is quite sizeable, with the steady-state predicted return often overestimating the steady-state actual return by more than ten percentage points. In addition, it is shown that when the variances of the alternative potential investments are not all equal,a limitation on the variance of the portfolio will reduce the magnitude of the bias. In many reasonable cases, constraining the portfolio variance reduces the bias by a magnitude greater than the amount by which it reduces the predicted portfolio return, causing the steady-state actual return to rise. This implies that return cannot automatically be assumed to be a monotonic function of risk.
Date: December 1972
Creator: Valentine, Jerome Lynn
Partner: UNT Libraries