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Achieving Financial Sustainability: Are We Asking the Wrong Questions?

Description: While technology has made producing copies of digital content almost entirely free, there is no escaping that publishing, according to most definitions of the term, still requires time and money. Any publishing service offered by a library must find a way to achieve financial sustainability—that is, operate without losing money. However, even "losing money" is a tricky concept, especially when taking into account varying definitions of operating expenses (overhead costs) under different models for auxiliary services. Libraries are by their very nature cost centers, providing services without the expectation of recovering revenue, and are usually part of larger organizations that similarly provide services under partial or full subsidies. While libraries are often comfortable with charging for convenience services and for services to those outside their designed community of users, careful thought should be given to which costs a publishing service-or any new service-should be expected to recover.
Date: August 12, 2016
Creator: Hawkins, Kevin S.
Partner: UNT Libraries

Investigation of a two-step nozzle in an 11-inch hypersonic tunnel

Description: Report discussing flow surveys made of several nozzles using two 2-dimensional steps at Mach number 6.98. Results regarding wall-pressure surveys, disturbance patterns in expansion, total-pressure survey, temperature recovery, and general nozzle characteristics are provided.
Date: October 25, 1949
Creator: McLellan, Charles H.; Williams, Thomas W. & Bertram, Mitchel H.
Partner: UNT Libraries Government Documents Department

Determination and use of the local recovery factor for calculating the effectiveness gas temperature for turbine blades

Description: In an in experimental investigation of local recovery factors for a blade having a pressure distribution similar to that of a typical reaction-type turbine blade, it a was found that the recovery factors were essentially independent of Mach number, Reynolds number, pressure gradient, and position on the blade surface except for regions where the boundary layer was probably in the transition range from laminar to turbulent. The recommended value of local subsonic recovery factor for use in calculating the effective gas temperature for gas turbine blades was 0.89.
Date: September 24, 1951
Creator: Esgar, Jack B. & Lea, Alfred L.
Partner: UNT Libraries Government Documents Department

The use of perforated inlets for efficient supersonic diffusion

Description: Report presenting the use of wall perforations on supersonic diffusers to avoid the internal contraction-ratio limitation. Experimental results on a preliminary model of a perforated diffuser at Mach number 1.85 are provided. A theoretical discussion of the flow coefficients and the size and spacing of the perforations are included.
Date: September 1956
Creator: Evvard, John C. & Blakey, John W.
Partner: UNT Libraries Government Documents Department

The use of perforated inlets for efficient supersonic diffusion

Description: Report presenting the use of wall perforations on supersonic diffusers to avoid the internal contraction-ratio limitation. Experimental results on a preliminary model of a perforated diffuser at Mach number 1.85 are provided. A theoretical discussion of the flow coefficients and the size and spacing of the perforations are included.
Date: June 25, 1947
Creator: Evvard, John C. & Blakey, John W.
Partner: UNT Libraries Government Documents Department

Effect of pressure recovery on the performance of a jet-propelled airplane

Description: Report presenting a study made to evaluate the effect of pressure recovery on the performance of a typical jet engine and a typical jet-propelled fighter airplane. Results regarding the efficiency parameters for air-induction systems, effect of ram-recovery ratio on the performance of a turbojet engine, and the effect of ram-recovery ratio on the performance of a turbojet airplane are provided.
Date: September 1948
Creator: Hanson, Frederick H., Jr. & Mossman, Emmet A.
Partner: UNT Libraries Government Documents Department

Comparison of effect of a turbojet engine and three cold-flow configurations on the stability of a full-scale supersonicle inlet

Description: Increasing the volume and length of the duct behind the inlet affected the inlet stability at Mach 2.0 and zero angle of attack. Close approximation of the inlet stability limit of the J34 engine-inlet configuration was obtained by a cold-pipe configuration having a length and volume approaching that measured to the engine turbine. Variation of these parameters had a small effect on the minimum subcritical stable mass flow below a cowl-lip-position parameter of 44 degrees and appeared to have a negligible effect on the inlet pressure-recovery - mass-flow curve. Initial buzz frequency and minimum cowl-lip-position parameter for complete buzz-free operation varied with configuration.
Date: January 24, 1957
Creator: Musial, Norman T.
Partner: UNT Libraries Government Documents Department

Characteristics of perforated diffusers at free-stream Mach number 1.90

Description: "An investigation was conducted at Mach number 1.90 to determine pressure recovery and mass-flow characteristics of series of perforated convergent-divergent supersonic diffusers. Pressure recoveries as high as 96 percent were obtained, but at reduced mass flows through the diffuser. Theoretical considerations of effect of perforation distribution on shock stability in converging section of diffuser are presented and correlated with experimental data. A method of estimating relative importance of pressure recovery and mass flow on internal thrust coefficient basis is given and a comparison of various diffusers investigated is made" (p. 1).
Date: May 8, 1950
Creator: Hunczak, Henry R. & Kremzier, Emil J.
Partner: UNT Libraries Government Documents Department

Effect of 40 degree sweepback on the spin and recovery characteristics of a 1/25-scale model of a typical fighter-type airplane as determined by free-spinning-tunnel tests

Description: Note presenting free-spinning-tunnel tests performed with a model of a typical fighter-type airplane to determine the effect of a 40 degrees sweepback on the spin and recovery characteristics. The characteristics were obtained for both a swept-wing and an unswept-wing configuration for a range of typical fighter loading conditions and two tail designs. The results indicated that for the model with a tail design considered unsatisfactory as regards spin recovery, sweeping the wings back 40 degrees improved the recovery characteristics.
Date: April 1947
Creator: Scher, Stanley H.
Partner: UNT Libraries Government Documents Department

Recovery temperatures and heat transfer near two-dimensional roughness elements at Mach 3.1

Description: Report presenting an investigation to determine the effect of single and multiple two-dimensional roughness elements on the temperature distribution, pressure distribution, and heat transfer at Mach 3.1. Results regarding recovery temperatures and heat transfer are provided.
Date: February 1958
Creator: Brinich, Paul F.
Partner: UNT Libraries Government Documents Department

Performance comparison at Mach numbers 1.8 and 2.0 of full-scale and quarter-scale translating-spike inlets

Description: From Summary: "The performance of a full-scale translating-spike inlet was obtained at Mach numbers of 1.8 and 2.0 and at angles of attack from 0 to 6 degrees. Comparisons were made between the full-scale production inlet configuration and a geometrically similar quarter-scale model. The inlet pressure-recovery, cowl pressure-distribution, and compressor-face distortion characteristics of the full-scale inlet agreed fairly well with the quarter-scale results. In addition, the results indicated that bleeding around the periphery ahead of the compressor-face station improved pressure recovery and compressor-face distortion, especially at angle of attack."
Date: October 21, 1957
Creator: Hearth, Donald P.; Anderson, Bernhard H. & Dryer, Murray
Partner: UNT Libraries Government Documents Department

Temperature recovery factors on a slender 12 degree cone-cylinder at Mach numbers from 3.0 to 6.3 and angles of attack up to 45 degrees

Description: Report presenting measurements of recovery temperatures on a slender cone-cylinder with a 12 degree vertex angle and a 1.25-inch-diameter cylinder for a range of Mach numbers. Results regarding the visual evidence, temperature distributions, pressure distributions, summary figures, correlation of temperature patterns with boundary-layer transition and separation, and recovery factors are provided.
Date: October 3, 1955
Creator: Reller, John O. & Hamaker, Frank M.
Partner: UNT Libraries Government Documents Department

A summary and analysis of data on dive-recovery flaps

Description: From Summary: "The results of numerous unrelated tests of dive-recovery flaps are collected in this report and presented in a form suitable for use in the preliminary design of dive-recovery flap installations. Since the data were obtained for airplane models of quite widely varying configurations, and are limited largely to a Mach number of 0.80, it is recommended that each new installation be carefully flight-tested before final approval. A flight-test procedure is outlined which will insure a maximum degree of safety."
Date: September 9, 1947
Creator: Boddy, Lee E. & Williams, Walter C.
Partner: UNT Libraries Government Documents Department

Preliminary investigation of the total-pressure-recovery characteristics of a symmetric and asymmetric nose inlet over a wide range of angle of attack at supersonic Mach numbers

Description: Report presenting an investigation of the total-pressure-recovery characteristics over a wide range of angles of attack of an axially symmetric nose inlet at a Mach number of 1.42 and an asymmetric nose inlet at Mach numbers of 1.42 and 1.84.
Date: December 9, 1953
Creator: Carter, Howard S. & Merlet, Charles F.
Partner: UNT Libraries Government Documents Department

An Analysis of the Economic and Institutional Factors Affecting Recovery by Local Governments from Huricanes

Description: This dissertation examines the impact of major hurricanes on changes in GDP for counties in four states – Alabama, Florida, Louisiana, and Texas. The analysis examines the effectiveness of intergovernmental financing for major hurricanes between 2000 and 2014. It also examines whether institutional proximity of the disaster management function to the Governor's Office and the career status of the director affect the speed of recovery from the disaster. The analysis also assesses the impact that a counties's prior experience at dealing with disasters has on the speed of recovery.
Date: August 2016
Creator: Short, Jesseca Elizabeth
Partner: UNT Libraries

Tests of a small-scale NACA submerged inlet at transonic Mach numbers

Description: Report presenting the pressure-recovery characteristics at the vertical center line of an NACA submerged inlet of aspect ratio 5 measured in the Mach number range of 0.60 to 1.08 by the wing-flow method. Variation of ram-recovery ratio determined from measurements at the center line of the inlet with test station Mach number is presented for mass-flow ratios of 0.30 to 0.60. Results regarding the pressure-recovery characteristics and application of the data to fuselage installations are provided.
Date: February 23, 1950
Creator: Rolls, L. Stewart & Rathert, George A., Jr.
Partner: UNT Libraries Government Documents Department

Comparison of effects of ailerons and combinations of spoiler-slot-deflector arrangements on spin recovery of sweptback-wing model having mass distributed along the fuselage

Description: Report presenting an investigation in the free-spinning tunnel to determine the effect of lateral-control systems using various combinations of spoilers, slots, and deflectors as compared with ailerons on the spin-recovery characteristics of a model of a 35 degree swept-wing fighter loaded heavily along the fuselage. Testing indicated that the ailerons were favorable for recovery when they were deflected full with the spin. Results regarding the effect of ailerons and two spoiler-slot-deflector configurations are provided.
Date: November 24, 1954
Creator: Healy, Frederick M. & Klinar, Walter J.
Partner: UNT Libraries Government Documents Department

Comparison of model and full-scale spin recoveries obtained by use of rockets

Description: Report presenting an investigation of a 1/19-scale model of an unswept-wing trainer airplane in the 20-foot free-spinning tunnel to determine the rocket spin-recovery characteristics of the model for comparison with available full-scale-airplane results. A rocket was attached to each wing tip to fire in a direction to apply an antispin yawing moment about the Z body axis. Results regarding the full-scale spin recoveries by rockets, model spin recoveries by rudder reversal, model spin recoveries by rockets, and mass changes associated with installation of emergency device are provided.
Date: February 1954
Creator: Burk, Sanger M., Jr. & Healy, Frederick M.
Partner: UNT Libraries Government Documents Department

Waste Heat Recovery Fluids for Heavy-Duty Transportation Bottoming Cycle Systems : A Summary Report

Description: Working fluids used in Rankine bottoming cycle systems for heat recovery from long-haul trucks, marine vessels, and railroad locomotives are examined. Rankine bottoming cycle systems improve fuel economy by converting the exhaust heat from the prime mover into useful power. The report assesses fluid property requirements on the basis of previous experience with bottoming cycle systems. Also, the exhaust gas characteristics for the transportation modes of interest are summarized and compared. Candidate working fluids are discussed with respect to their potential for use in Rankine bottoming cycle systems. Analytical techniques are presented for calculating the thermodynamic properties of single-component working fluids. The resulting equations have been incorporated into a computer code for predicting the performance of Rankine bottoming cycle systems. In evaluating candidate working fluids, the code requires the user to input only a minimal amount of fluid property data.
Date: September 1983
Creator: Krazinski, J. L.; Uherka, K. L.; Holtz, Robert E. & Ash, J. E.
Partner: UNT Libraries Government Documents Department

Experimental investigation at supersonic speeds of side scoops employing boundary-layer suction

Description: Report presenting the pressure-recovery characteristics of a model with two scoops situated on the aft position of a long forebody and connected through diffusors to a common settling chamber at a range of Mach numbers. The effects of interaction between the flow in the two air-induction systems and of varying the mass flow through the boundary-layer scoops were studied. Results at several different angles of attack are provided.
Date: December 12, 1949
Creator: Edwards, Sherman S.
Partner: UNT Libraries Government Documents Department

A preliminary investigation of methods for improving the pressure recovery characteristics of variable-geometry supersonic-subsonic diffuser systems

Description: Report presenting an investigation to study methods for improving the pressure-recovery characteristics of two-dimensional, variable-geometry, supersonic-subsonic diffuser systems. Results without injection, with injection, and effect of diffuser configuration on wind-tunnel performance are provided.
Date: October 16, 1957
Creator: Hasel, Lowell E. & Sinclair, Archibald R.
Partner: UNT Libraries Government Documents Department

Experimental investigation of temperature recovery factors on a 10 degree cone at angle of attack at a Mach number of 3.12

Description: Report presenting temperature recovery factors on a thin-walled, metal, 10 degree included angle cone at a Mach number of 3.12 over a range of angles of attack and Reynolds numbers per foot. An increase in angle of attack was found to increase the equilibrium surface temperatures in the laminar and turbulent boundary-layer regions.
Date: July 1954
Creator: Jack, John R. & Moskowitz, Barry
Partner: UNT Libraries Government Documents Department