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Manifest Anxiety and Task as Determiners of Performance in Paired Associate Learning

Description: The purpose of the present study was to investigate the relationship between drive level, defined in terms of scores on the Taylor Manifest Anxiety Scale, and performance in a complex paired-associate learning task, in which an attempt was made to control the number and strength of the competing responses.
Date: August 1965
Creator: Brown, Bill Rondol
Partner: UNT Libraries

An Analysis of Teacher Performance Evaluation Policies and Criteria in Texas Public Schools

Description: The purposes of this study were to identify the procedures and criteria used for conducting teacher performance evaluation in Texas public schools, to determine the degree to which teacher performance evaluation procedures and instruments reflect the stated evaluation policies of Texas public schools, and to determine the degree to which teacher performance evaluation instruments used in Texas public schools reflect presage criteria (teacher characteristics) as opposed to process criteria (teacher behavior) as opposed to product criteria (student change or gain) as opposed to general job performance requirements (job expectations). The main findings include the following. (1) Teacher performance evaluation is required in all Texas public school districts and is often performed several times a year by more than one observer. The building principal is the key person involved in this process. (2) Although all school districts stated the supervisory function of the improvement of instruction as the major purpose of their teacher performance evaluation policy, a large number of school districts utilize teacher performance evaluation for the administration functions of serving as a basis for retention or dismissal. (3) If in reality teacher performance evaluation were construed as the improvement of instruction or teaching performance, it should be predictable that process criteria (teacher behavior) would account for the majority of items in the evaluation instruments. However, these items accounted for only about one-fourth of the total number. At the same time, items relating to general job requirements accounted for over 50 percent of the items. This exhibits a maintenance rather than teaching thrust. (4) The data gathered on current teacher performance evaluation instruments appear to be highly pertinent to maintaining the school as an organization and appear to be helpful in making personnel decisions. (5) Teacher performance evaluation instruments in Texas public schools are much more heavily weighted toward assessing ...
Date: December 1986
Creator: Marlin, Thomas William
Partner: UNT Libraries

Rhapsody in Green - A Happening: An Examination of the Happening as a Rhetorical Tool

Description: In this study I outline seven characteristics of a traditional Happening (the use of games and play, an inherent intertextual element, an emphasis on place/space, an element/spirit of anarchy, an element of chance, an emphasis on the fusion of art with everyday life, and the existence of both a purpose and a meaning) and seek to determine which characteristics contribute to the Happening's current usage as a rhetorical tool. I created a traditional Happening containing a message of environmental consumption and destruction, and surveyed audience members regarding their interpretation and experience. The survey responses were coded using a top-down narrative analysis. I discovered that intertextuality, place/space, and the fusion of art with everyday life are particularly effective communicators of a message in a socially or politically conscious Happening.
Date: December 2004
Creator: Walker, Rebecca Ann
Partner: UNT Libraries

Test Anxiety and Performance on the Wechsler Intelligence Scale for Children

Description: Although the significance of anxiety has long been recognized and explored within the framework of psychoanalysis, it was not until after World War II that it began to influence research in psychology. The manipulation of anxiety as a research variable has taken place both within and without the framework of psychoanalytic theory. The primary purpose of the present study was to determine the relationship between test anxiety, as determined by scores on the TASC, and performance on the Wechsler Intelliaence Scale for Children. TASC scores were compared to Verbal Scale, Performance Scale, Full Scale, and individual subtest scores on the WISC.
Date: January 1968
Creator: Leonard, Mary Lois
Partner: UNT Libraries

NACA Conference on Aircraft Structures

Description: This document contains reproductions of technical papers on some of the most recent research results on aircraft structures from the NACA Laboratories. These papers were presented by members of the staff of the NACA Laboratories at the NACA conference held at the Langley Aeronautical Laboratory March 7, 1951. The purpose of this conference was to convey to those involved in the study of aircraft structures these recent research results and to provide those attending an opportunity for discussion of these results. The papers in this document are in the same form in which they were presented at the conference so that distribution of them might be prompt. The original presentation and this record are considered as complimentary to, rather than as substitute for, the Committee?s system of complete and formal reports.
Date: March 7, 1951
Partner: UNT Libraries Government Documents Department

Detail Calculations of the Estimated Shift in Stick-Fixed Neutral Point Due to the Windmilling Propeller and to the Fuselage of the Republic XF-12 Airplane

Description: Detail calculations are presented of the shifts in stick-fixed neutral point of the Republic XF-12 airplane due to the windmilling propellers and to the fuselage. The results of these calculations differ somewhat from those previously made for this airplane by Republic Aviation Corporation personnel under the direction of Langley flight division personnel. Due to these differences the neutral point for the airplane is predicted to be 37.8 percent mean aerodynamic chord, instead of 40.8 percent mean aerodynamic chord as previously reported.
Date: October 16, 1944
Creator: White, M. D.
Partner: UNT Libraries Government Documents Department

An Evaluation of Correspondence between Preference and Performance under a Progressive Ration Schedule with College Students

Description: Preference assessments are used in clinical settings to identify stimuli with reinforcing potential. The progressive-ratio schedule has shown to be useful in clinical assessments in identifying stimuli with stronger reinforcer efficacy that corresponds to formalized assessments.The current study utilized a progressive-ratio schedule to compare videos of high and low preference assessed by verbal reports of preference with college students. Results indicated breakpoints were higher for high preferred videos than low preferred videos for three out of five participants, but preference was not indicative of performance.
Date: December 2016
Creator: Johnson, Jamarious
Partner: UNT Libraries

Wind Tunnel Development of Means to Alleviate Buffeting of the North American XP-82 Airplane at High Speeds

Description: This report presents the results of wind-tunnel tests of a 0.22-scale model of the North American XP-82 airplane with several modifications designed to reduce the buffeting of the airplane. The effects of various modifications on the air flow over the model are shown by means of photographs of tufts. The drag, lift, and pitching-moment coefficients of the model with several of the modifications are shown. The result indicate that, by reflexing the trailing edge of the center section of the wing and modifying the radiator air-scoop gutter and the inboard lower-surface wing fillets, the start of buffeting can be delayed from a Mach number of 0.70 to 0.775, and that the diving tendency of the airplane would be eliminated up to a Mach number of 0.80.
Date: January 9, 1947
Creator: Anderson, Joseph L.
Partner: UNT Libraries Government Documents Department

Performance of the Modified V-1710-93 Engine-Stage Supercharger with a Constant-Area Vaneless Diffuser

Description: As part of an investigation to increase the power output of the V-1710-93 engine at altitude, the engine-stage supercharger was combined with a constant-area vaneless diffuser designed to improve the performance of the engine-stage supercharger at the rated engine operating point. The performance of the modified supercharger was investigated in a variable-component supercharger test rig and compared with that of the standard supercharger with an 8-vaned diffuser. A separate evaluation of the component efficiencies and a study of the flow characteristics of the modified supercharger was made possible by internal diffuser instrumentation. At the volume flow required by the engine for rated operating conditions, the modified supercharger increased the over-all adiabatic efficiency 0.05 and the over-all pressure coefficient 0.035. Furthermore, the capacity of the engine-stage supercharger was increased by replacing the standard 8-vaned diffuser with the vaneless diffuser. The peak over-all adiabatic efficiency for the modified supercharger, however, was 0.05 to 0.07 lower than that of the standard unit over the range of tip speeds investigated. The improved performance of the modified supercharger at rated engine operating conditions resulted from a shift of the point of peak adiabatic efficiency and pressure coefficient of the standard supercharger to a higher flow. The energy loss through the vaneless diffuser was found to be small. Because of the restricted diffuser diameter, however, diffusion was inadequate, which resulted in a relatively small static-pressure rise through the diffuser, high diffuser-exit velocities, and excessive collector-case losses.
Date: December 20, 1946
Creator: Douglas, John E. & Schwartz, Irving R.
Partner: UNT Libraries Government Documents Department

Preliminary Results of an Altitude-Wind-Tunnel Investigation of an Axial-Flow Gas Turbine-Propeller Engine, 4, Compressor and Turbine Performance Characteristics

Description: As part of an investigation of the performance and operational characteristics of the axial-flow gas turbine-propeller engine, conducted in the Cleveland altitude wind tunnel, the performance characteristics of the compressor and the turbine were obtained. The data presented were obtained at a compressor-inlet ram-pressure ratio of 1.00 for altitudes from 5000 to 35,000 feet, engine speeds from 8000 to 13,000 rpm, and turbine-inlet temperatures from 1400 to 2100 R. The highest compressor pressure ratio obtained was 6.15 at a corrected air flow of 23.7 pounds per second and a corrected turbine-inlet temperature of 2475 R. Peak adiabatic compressor efficiencies of about 77 percent were obtained near the value of corrected air flow corresponding to a corrected engine speed of 13,000 rpm. This maximum efficiency may be somewhat low, however, because of dirt accumulations on the compressor blades. A maximum adiabatic turbine efficiency of 81.5 percent was obtained at rated engine speed for all altitudes and turbine-inlet temperatures investigated.
Date: August 10, 1948
Creator: Wallner, Lewis E. & Saari, Martin J.
Partner: UNT Libraries Government Documents Department

Preliminary Results of British Nene II Engine Altitude-Chamber Performance Investigation. I - Altitude Performance Using Standard 18.75-Inch-Diameter Jet Nozzle, 1, Altitude Performance Using Standard 18.75-Inch-Diameter Jet Nozzle

Description: An investigation is being conducted to determine the altitude performance characteristics of the British Nene II engine and its components. The present paper presents the preliminary results obtained using a standard jet nozzle. The test results presented are for conditions simulating altitudes from sea level to 60,000 feet and ram pressure ratios from 1.0 to 2.3. These ram pressure ratios correspond to flight Mach numbers between zero and 1.16 assuming a 100 percent ram recovery.
Date: May 24, 1948
Creator: Barson, Zelmar & Wilsted, H. D.
Partner: UNT Libraries Government Documents Department

Investigation of Porous Gas-Heated Leading-Edge Section for Icing Protection of a Delta Wing

Description: A tip section of a delta wing having an NACA 0004-65 airfoil section and a 600 leading-edge sweepback was equipped with a porous leading-edge section through which hot gas was 'bled for anti-icing. Heating rates for anti-icing were determined for a wide range of icing conditions. The effects of gas flow through the porous leading-edge section on airfoil pressure distribution and drag in dry air were investigated. The drag increase caused by an ice formation on the unheated airfoil was measured for several icing conditions. Experimental porous surface- to free-stream convective heat-transfer coefficients were obtained in dry air and compared with theory. Adequate icing protection was obtained at all icing conditions investigated. Savings in total gas-flow rate up to 42 percent may be obtained with no loss in anti-icing effectiveness by sealing half the upper-surface porous area. Gas flow through the leading-edge section had no appreciable effect on airfoil pressure distribution. The airfoil section drag increased slightly (5-percent average) with gas flow through the porous surface. A heavy glaze-ice formation produced after 10 minutes of icing caused an increase in section drag coefficient of 240 percent. Experimental convective heat-transfer coefficients obtained with hot-gas flow through the porous area in dry air and turbulent flow were 20 to 30 percent lower than the theoretical values for a solid surface under similar conditions. The transition region from laminar to turbulent flow moved forward as the ratio of gas velocity through the porous surface to air-stream velocity was increased.
Date: January 19, 1955
Creator: Bowden, Dean T.
Partner: UNT Libraries Government Documents Department

Investigation of Operating Characteristics of an Engine Equipped with Modifications to Eliminate Fuel-Evaporation Icing

Description: Two modified fuel-injection systems, a drilled-inducer type and a spinner type, that prevent serious fuel-evaporation icing were installed on a V-type, liquid-cooled aircraft engine and a preliminary investigation was conducted to determine the effect on engine operating characteristics. The spinner system was also ground - and flight tested on a twin-engine fighter airplane. Flight measurements of cylinder-head temperature over a range of fuel-air ratios and engine power conditions were made at an altitude of approximately 10,000 feet. Starting and accelerating of the engine on the ground were unaffected by the fuel-injection modifications. During the flight investigation, no appreciable variation occurred between the maximum and minimum cylinder-head temperature with the standard and modified system for the same power condition and no irregularity of mixture distribution could be detected throughout the power range of the engine. Normal mixture distribution was also indicated by a similar response of cylinder-head temperature for variations of fuel-air ratio at manifold pressures of 25 and 35 inches of mercury absolute. Both modified fuel-injection systems required less fuel-nozzle pressure than the standard system to obtain the desired fuel-air ratio for given air-flow condition.
Date: December 24, 1946
Creator: Mulholland, Donald R. & Zlotowski, Edward D.
Partner: UNT Libraries Government Documents Department

Wind-Tunnel Tests of a 0.16-Scale Model of the Douglas MX-656 Airplane at High Subsonic Speeds. II - Wing and Fuselage Pressure Distribution

Description: Measurements of wing and fuselage pressure distributions were made at low and high subsonic Much numbers on a 0.16-scale model of the projected MX-656 research airplane. The MX-656 is a supersonic design utilizing a low-aspect-ratio wing and tail. Pressure-distribution measurements indicated that, although the critical Mach number of the wing was approximately 0.81 at 0 degree angle of attack, compressibility effects were of little significance below a Mach number of at least 0.90. The principal effect of compressibility was an increase in the pressure gradient over the after 30 percent of the wing chord, causing a tendency for the flow to separate. At 0.40 Mach number, the wing stalled abruptly at approximately 12 deg, angle of attack. The wing-pressure distribution showed this stall was a result of complete separation of the flow from the upper surface of the wing, Deflecting the leading-edge flaps delayed the stall to a higher angle of attack with some increase in the maximum section normal force,.
Date: August 22, 1949
Creator: Cleary, Joseph W. & Mellenthin, Jack A.
Partner: UNT Libraries Government Documents Department

Tests of Submerged Duct Installation on the Ryan FR-1 Airplane in the Ames 40- by 80-Foot Wind Tunnel

Description: An investigation of an NACA submerged intake installation on the Ryan FR-1 was conducted to determine the full-scale aerodynamic characteristics of this installation. In addition, tests were conducted on the submerged inlet with revised entrance lips and deflectors to determine the configuration which would result in the best dynamic pressure recovery measured at the inlet for this installation without a major rework of the entrance. Stalling of the air flow over the inner lip surface created excessive dynamic pressure losses with the original entrance. The revised entrance produced a 12-percent increase in dynamic pressure recovery at the design high-speed inlet-velocity ratio and resulted in an improvement of thte critical-speed characteristics of the entrance lip. A complete redesign of the entrance including a decrease in ramp angle and adjustment of lip camber is necessary to secure optimum results from this submerged duct installation.
Date: April 23, 1947
Creator: Martin, Norman J.
Partner: UNT Libraries Government Documents Department

Altitude-Wind-Tunnel Investigation of a 3000-Pound-Thrust Axial-Flow Turbojet Engine, 6, Analysis of Effects of Inlet Pressure Losses

Description: The losses in the inlet air ducts, the diffusers, and the de-icing equipment associated with turbojet engine installations cause a reduction in the total pressure at the inlet of the engine and result in reduced thrust and increased specific fuel consumption. An analytical evaluation of the effects of inlet losses on the net thrust and the fuel economy of a 3000-pound-thrust axial flow turbojet engine with a two-stage turbine is presented. The analysis is based on engine performance characteristics that were determined from experiments in the NACA Cleveland altitude wind tunnel. The experimental investigation did not include tests in which inlet losses were systematically varied, but the effects of these losses can be accurately estimated from the experimentally determined performance characteristics of the engine.
Date: 1948
Creator: Sanders, Newell D. & Palasics, John
Partner: UNT Libraries Government Documents Department

Wind-Tunnel Investigation of the Static Lateral Stability Characteristics of Wing-Fuselage Combinations at High Subsonic Speeds

Description: A systematic research program is being carried out in the Langley high-speed 7- by 10-foot tunnel to determine the aerodynamic characteristics of various arrangements of the component parts of research-type airplane models, including some complete model configurations. Data are being obtained on characteristics in pitch, sideslip, and during steady roll at Mach numbers from 0.40 to about 0.95. This paper presents results which show the effect of taper ratio on the aerodynamic characteristics in sideslip of wing-fuselage combinations having wings with a sweep of 45 degrees at the quarter-chord line, an aspect ratio of 4, and a NACA 65A006 airfoil section.
Date: April 10, 1953
Creator: Wiggins, James W. & Fournier, Paul G.
Partner: UNT Libraries Government Documents Department

Tank Tests of 1/5.5-Scale Forward Dynamic Model of the Columbia XJL-1 Amphibian - Langley Tank Model 208, TED No. NACA 2336

Description: Tests of a powered dynamic model of the Columbia XJL-1 amphibian were made in Langley tank no.1 to determine the hydrodynamic stability and spray characteristics of the basic hull and to investigate the effects of modifications on these characteristics. Modifications to the forebody chime flare, the step, and the afterbody, and an increase in the angle of incidence of the wing were included in the test program. The seaworthiness and spray characteristics were studied from simulated taxi runs in smooth and rough water. The trim limits of stability, the range of stable positions of the enter of gravity for take-off, and the landing stability were determined in smooth water. The aerodynamic lift, pitching moment, and thrust were determined at speeds up to take-off speed.
Date: November 13, 1946
Creator: Havens, Robert F.
Partner: UNT Libraries Government Documents Department