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Investigation of the Kansas City Hyatt Regency Walkways Collapse

Description: Report issued by the National Bureau of Standards documenting investigations conducted on construction failures of two suspended walkways in a Kansas City hotel. It includes tables, illustrations, photographs, and other details of the investigation.
Date: May 1982
Creator: Marshall, Richard D.; Pfrang, E. O.; Leyendecker, Edgar V.; Woodward, K. A.; Reed, R. P.; Kasen, M. B. et al.
Partner: UNT Libraries Government Documents Department
open access

Regulatory Incentives for Electricity Transmissions-Issues and Cost Concerns

Description: This report will focus on issues related to the need for transmission incentives, and consumer cost concerns related to these incentives. Given the changes that FERC cites in the electric industry, the question arises as to whether the need for transmission incentives continues. FERC is bound by EPACT to make incentives available, and is not proposing to end the incentives. However, with concerns raised over the effects of transmission incentives on consumer rates, implications of related federal policies on the electric power sector, additional FERC regulatory policies for transmission, and the aging of electricity infrastructure among key issues, the need for continuing transmission incentives may be a matter for Congress to consider.
Date: October 28, 2011
Creator: Campbell, Richard J.
Partner: UNT Libraries Government Documents Department
open access

An Analysis of the Effect of Environmental and Systems Complexity on Information Systems Failures

Description: Companies have invested large amounts of money on information systems development. Unfortunately, not all information systems developments are successful. Software project failure is frequent and lamentable. Surveys and statistical analysis results underscore the severity and scope of software project failure. Limited research relates software structure to information systems failures. Systematic study of failure provides insights into the causes of IS failure. More importantly, it contributes to better monitoring and control of projects and enhancing the likelihood of the success of management information systems. The underlining theories and literature that contribute to the construction of theoretical framework come from general systems theory, complexity theory, and failure studies. One hundred COBOL programs from a single company are used in the analysis. The program log clearly documents the date, time, and the reasons for changes to the programs. In this study the relationships among the variables of business requirements change, software complexity, program size and the error rate in each phase of software development life cycle are tested. Interpretations of the hypotheses testing are provided as well. The data shows that analysis error and design error occur more often than programming error. Measurement criteria need to be developed at each stage of the software development cycle, especially in the early stage. The quality and reliability of software can be improved continuously. The findings from this study suggest that it is imperative to develop an adaptive system that can cope with the changes to the business environment. Further, management needs to focus on processes that improve the quality of the system design stage.
Date: August 2001
Creator: Zhang, Xiaoni
Partner: UNT Libraries
open access

A Test of Catastrophe Theory Applied to Corporate Failure

Description: Catastrophe theory (CT) is a relatively new mathematical theory that comprehensively describes a system exhibiting discontinuous behavior when subjected to continuous stimuli. This study tests the theory using capital-market data. The data is a time series of stock returns on firms that filed for Chapter 11 reorganization during 1980-1985. The CT model used is based on a corporate failure model suggested by Francis, Hastings and Fabozzi (1983). The model predicts 1) as the filing date approaches, there will be a structural shift in the underlying stock-return generating process of the filing firm, and 2) firms with lower operating risk will have a smaller jump than firms with higher operating risk, corresponding to their relative positions within the bifurcation set of the catastrophe cusp.
Date: August 1987
Creator: Gregory-Allen, Russell B. (Russell Brian)
Partner: UNT Libraries
open access

Handbook of Structural Stability Part 4: Failure of Plates and Composite Elements

Description: Available theories on failure of flat plates are reviewed, and test data on the postbuckling behavior, effective width, and failure of flat curved plates are correlated. Test data on the crippling strength of various formed and extruded shapes are reviewed, from which a generalized method of crippling analysis is formulated. This analysis is then applied to a variety of sections and materials in common use.
Date: August 1957
Creator: Gerard, George
Partner: UNT Libraries Government Documents Department
open access

Propeller vibrations and the effect of the centrifugal force

Description: A method has been devised for determining the frequencies of the various modes of a stationary propeller and the associated crankshaft. A method has also been devised to obtain the effect of the centrifugal force on a revolving propeller by use of a flexible model.
Date: February 1935
Creator: Theodorsen, T.
Partner: UNT Libraries Government Documents Department
open access

Factors That Affect Operational Reliability of Turbojet Engines

Description: The problem of improving operational reliability of turbojet engines is studied in a series of papers. Failure statistics for this engine are presented, the theory and experimental evidence on how engine failures occur are described, and the methods available for avoiding failure in operation are discussed. The individual papers of the series are Objectives, Failure Statistics, Foreign-Object Damage, Compressor Blades, Combustor Assembly, Nozzle Diaphrams, Turbine Buckets, Turbine Disks, Rolling Contact Bearings, Engine Fuel Controls, and Summary Discussion.
Date: January 31, 1956
Creator: Lewis Laboratory Staff
Partner: UNT Libraries Government Documents Department
open access

Application of Statistical Methods to Study of Gas-Turbine Blade Failures

Description: Note presenting an investigation conducted to determine the applicability of statistical methods as an approach to the evaluation of materials for use in gas turbines by determining the frequency distribution of time until failure of gas-turbine blades. Two wheels, each incorporating 142 inserted blades of a cast cobalt-base heat-resistant alloy, were tested. The results indicated that the time for first failure may not generally be taken as an accurate indication of the performance of the average blade.
Date: June 1948
Creator: Hoffman, Charles A. & Ault, G. Mervin
Partner: UNT Libraries Government Documents Department
open access

Experimental Study of Torsional Column Failure

Description: "Thirty-three 24ST aluminum-alloy 2- by 2- by 0.10-inch channels, with lengths ranging from 10 to 90 inches were tested at Stanford University in compression to obtain an experimental verification of the theoretical formulas for torsional failure developed by Eugene E. Lundquist of the N.A.C.A. The observed critical loads and twist-axis locations were sufficiently close to the values obtained from the formulas to establish the substantial validity of the latter. The differences between observed and computed results were small enough to be accounted for by small and mostly unavoidable differences between actual test conditions and those assumed in deriving the formulas" (p. 1).
Date: October 1939
Creator: Niles, Alfred S.
Partner: UNT Libraries Government Documents Department
open access

Designation of Global 'Too Big To Fail' Firms

Description: This report provides background on the the Financial Stability Board's (FSB) designation process for systemically significant financial institutions, but takes no position on any potential benefits or shortcomings of that process.
Date: October 29, 2015
Creator: Miller, Rena S. & Jackson, James K.
Partner: UNT Libraries Government Documents Department
open access

The Federal Deposit Insurance Corporation (FDIC): Summary of Actions in Support of Housing and Financial Markets

Description: This report discusses recent actions taken by the Federal Deposit Insurance Corporation (FDIC) in support of housing and financial markets, including: a temporary increase in deposit insurance as required by the Emergency Economic Stabilization Act of 2008 (P.L. 110-343), the resolution of bank failures, the development of the Temporary Liquidity Guarantee Program (TLGP), and efforts to reduce foreclosures.
Date: March 5, 2009
Creator: Gonzales, Oscar R. & Getter, Darryl E.
Partner: UNT Libraries Government Documents Department
open access

Susceptibility to Welding Cracking, Welding Sensitivity, Susceptibility to Welding Seam Cracking, and Test Methods for These Failures

Description: "In the years after the First World war a very rapid development, which even today has by no means come to an end, took place in the field of welding; here also, as in most technical innovations, failures made their appearance. Thereupon comprehensive Investigations were undertaken by steel manufacturers and consumers with cooperation of the authorities. In most cases the reasons for failure could be determined and eliminated and further occurrences avoided by the use of new test methods" (p. 1).
Date: June 1949
Creator: Zeyen, K. L.
Partner: UNT Libraries Government Documents Department
open access

Tests of Aerodynamically Heated Multiweb Wing Structures in a Free Jet at Mach Number 2: An Aluminum-Alloy Model of 40-Inch Chord With 0.125-Inch-Thick Skin

Description: Report presenting testing of a 5-percent-thick 2024-T3 aluminum-alloy multiweb wing (MW-1-(2)) at a Mach number of 2 under simulated supersonic flight conditions. The wing experienced dynamic failure as a result of catastrophic flag-waving flutter due to the combined action of aerodynamic heating and loading. Results regarding model temperatures, experimental pressures, strain results, accelerometer, and model failure are provided.
Date: June 23, 1958
Creator: Griffith, George E. & Miltonberger, Georgene H.
Partner: UNT Libraries Government Documents Department
open access

A Theory for Primary Failure of Straight Centrally Loaded Columns

Description: "A theory of primary failure of straight centrally loaded columns is presented. It is assumed that the column cross section and the load are constant throughout the length. Primary failure is defined as any type of failure in which the cross sections are translated, rotated, or translated and rotated but not distorted in their own planes" (p. 141).
Date: August 17, 1936
Creator: Lundquist, Eugene E. & Fligg, Claude M.
Partner: UNT Libraries Government Documents Department
open access

Three Essays in Business Failure

Description: This dissertation consists of three essays exploring market reactions to business failure. In the first essay, the filing strategies are divided into three basic types, voluntary, involuntary and prepackaged. The second essay provides insight into industry wide factors impacting assimilation of information by the market. The third essay provides a view of the GARCH-M model in measuring a risk premium as a firm approaches bankruptcy.
Date: May 1997
Creator: Theis, John D. (John Dennis)
Partner: UNT Libraries
open access

Tests of Aerodynamically Heated Multiweb Wing Structures in a Free Jet at Mach Number 2: Two Aluminum-Alloy Models of 20-Inch Chord With 0.064- and 0.081-Inch-Thick Skin

Description: Report presenting testing of two 2024-T3 aluminum-alloy multiweb wing structures (MW-2 and MW-3), similar to airplane or missile wings, at a Mach number of 2 under simulated supersonic flight conditions. Results regarding experimentally determined test conditions, model temperatures, strain-gage results, and model failures are provided. The report indicates that much of the stress data does not agree with expected results, but there is too much uncertainty regarding the reduction of strain data that no conclusions can be made concerning the results.
Date: August 9, 1955
Creator: Griffith, George E.; Miltonberger, Georgene H. & Rosecrans, Richard
Partner: UNT Libraries Government Documents Department
open access

Effectiveness of Ceramic Coatings in Reducing Corrosion of Five Heat-Resistant Alloys by Lead-Bromide Vapors

Description: Note presenting testing to determine whether lead compounds in the combustion products of high-octane fuel are a contributing factor in causing failures of the heat-resistant alloy parts in aircraft exhaust systems. To obtain answers for five heat-resistant alloys, a test was devised in which the alloy specimens in an uncoated condition, in a preoxidized condition, and with three different ceramic coatings were exposed for 6 hours to lead-containing vapors in an air atmosphere at 3 different temperatures.
Date: June 1951
Creator: Moore, Dwight G. & Mason, Mary A.
Partner: UNT Libraries Government Documents Department
open access

Vibration Survey of Blades in 10-Stage Axial-Flow Compressor 1: Static Investigation

Description: "An investigation was conducted to determine the cause of failures in the seventh- and tenth-stage blades of an axial-flow compressor. The natural frequencies of all rotor blades were measured and critical-speed diagrams were plotted. These data show that the failures were possibly caused by resonance of a first bending-mode vibration excited by a fourth order of the rotor speed in the seventh stage and a sixth order in the tenth stage" (p. 1).
Date: January 31, 1949
Creator: Meyer, André J., Jr. & Calvert, Howard F.
Partner: UNT Libraries Government Documents Department
open access

Investigation of mechanisms of blade failure of forged Hastelloy B and cast Stellite 21 turbine blades in turbojet engine

Description: An investigation was conducted to study the mechanisms of blade failure of forged Hastelloy B and cast Stellite 21. The blades were mounted in a 16-25-6 alloy rotor and subjected to 20-minute cycles consisting of 15 minutes at rated speed and approximately 5 minutes at idle. The first failures of the Hastelloy B and Stellite 21 blades were probably the result of excessive vibratory stresses and occurred after 14.25 and 16.75 hours, respectively. After 28.75 hours of operation, all but 3 of the original 25 Hastelloy B blades had either failed or contained stress-rupture-type cracks and four of the original 27 Stellite 21 blades contained stress-rupture-type cracks.
Date: August 22, 1951
Creator: Yaker, C.; Robards, C. F. & Garrett, F. B.
Partner: UNT Libraries Government Documents Department
open access

Wind-tunnel investigation of a 1/6-scale model of the Bumblebee XPM missile at high subsonic speeds

Description: Report presenting the results of an investigation of a model of the Bumblebee XPM missile to determine the causes of booster-fin failures on full-scale missiles. Results indicated that failures of the fins were due to launching shoes which caused the missile to try at increasingly negative angles of attack as the Mach number increased.
Date: December 11, 1950
Creator: Nelson, Warren H.
Partner: UNT Libraries Government Documents Department
open access

Failure of Materials Under Combined Repeated Stresses With Superimposed Static Stresses

Description: Note presenting a review of experiments on biaxial alternating stresses and simple combinations of static stress with alternating stress, which is shown to lead to a general criterion for the effect of static stress on the permissible amplitude of alternating stress. Tests were performed to determine the effect of static compression on alternating torsion, which is the one simple combination that had not been previously investigated. The results agree with the criterion.
Date: November 1955
Creator: Sines, George
Partner: UNT Libraries Government Documents Department
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