18,988 research outputs found
Apollo experience report guidance and control systems
The Apollo guidance and control systems for both the command module and the lunar module are described in a summary report. General functional requirements are discussed, and general functional descriptions of the various subsystems and their interfaces are provided. The differences between the original in-flight maintenance concept and the final lunar-orbital-rendezvous concept are discussed, and the background in philosophy, the system development, and the reasons for the change in concept are chronologically presented. Block diagrams showing the command module guidance and control system under each concept are included. Significant conclusions and recommendations contained in more detailed reports on specific areas of the guidance and control systems are included
The Variable Polarity Plasma Arc Welding Process: Its Application to the Space Shuttle External Tank
This report describes progress in the implementation of the Variable Polarity Plasma Arc Welding (VPPAW) process at the External Tank (ET) assembly facility. Design allowable data has been developed for thicknesses up to 1.00 in. More than 24,000 in. of welding on liquid oxygen and liquid hydrogen cylinders has been made without an internal defect
Construction and Software Design for a Microcomputer Controlled pH/Ion Titrator
The construction of an automated titration device is described. The major components include an Apple II+ Microcomputer and 8-bit parallel interface. Fisher Accumet, Model 520 Digital pH/lon Meter, Gilmont Micrometer Buret of 2.5 mL capacity, Sigma stepper motor, power supply and driver to operate the buret, and a constant temperature bath of ± 0.005 °C stability. The limitations of the system are 0.001 pH/0.1 mv for the pH/ion sensing system, and 0.125 μL per step for the buret. The system as described is designed to determine equilibrium constants for metal ion-amino acid complexes. By changing the software a variety of different pH and redox titration experiments may be performed. A computer program used to operate the stepper motor driven syringe buret and record the pH from a digital pH meter is described. The program uses both Apple BASIC and assembly language. This is a closed loop operation in which the data from the pH meter is used to control the amount of reagent delivered by the buret. The results are displayed graphically as the titration proceeds. The variance of the pH readings are calculated using an assembly language subroutine and the calculations are done with zero round-off error
Radiometric responsivity determination for Feature Identification and Location Experiment (FILE) flown on space shuttle mission
A procedure was developed to obtain the radiometric (radiance) responsivity of the Feature Identification and Local Experiment (FILE) instrument in preparation for its flight on Space Shuttle Mission 41-G (November 1984). This instrument was designed to obtain Earth feature radiance data in spectral bands centered at 0.65 and 0.85 microns, along with corroborative color and color-infrared photographs, and to collect data to evaluate a technique for in-orbit autonomous classification of the Earth's primary features. The calibration process incorporated both solar radiance measurements and radiative transfer model predictions in estimating expected radiance inputs to the FILE on the Shuttle. The measured data are compared with the model predictions, and the differences observed are discussed. Application of the calibration procedure to the FILE over an 18-month period indicated a constant responsivity characteristic. This report documents the calibration procedure and the associated radiometric measurements and predictions that were part of the instrument preparation for flight
Criminal Procedure - Presumed Guilty: The Use of Videotaped and Closed-Circuit Televised Testimony in Child Sex Abuse Prosecutions and the Defendant\u27s Right to Confrontation - Coy v. Iowa
This Note proposes that those statutes which permit admission of videotaped testimony and most uses of closed-circuit televised testimony violate a criminal defendant\u27s sixth amendment right to confront his accusers. In Coy v. Iowa, the United States Supreme Court recently held that one state\u27s practice of shielding the defendant from the view of the child witness during the child\u27s testimony violated the defendant\u27s right to confrontation. Following the Court\u27s analysis, this Note discusses the various problems arising from the use of videotaped or closed-circuit televised testimony. Concluding that the admission of such testimony is not a constitutionally permissible substitute for face to face, physical confrontation, this Note will offer alternative solutions to the problem of protecting the child witness without infringing the constitutional rights of the criminal defendant
An Examination of Auditor Changes Following Events Adversely Affecting External Auditor Credibility.
This study examines auditor changes following events adversely affecting auditor credibility. Disciplinary actions against auditors by the Securities and Exchange Commission (SEC) are posited to be events damaging to auditor credibility. Agency theory and prior research are used to generate hypotheses about differences between client firms that switch auditors and client firms that do not switch auditors after an SEC action under Rule 2(e) against their auditor. A series of univariate and multivariate statistical tests are conducted on the sample firms. The sample is divided into a Switch group and a Non-Switch group. The sample as a whole is examined, as well as subgroups of clients of Big Eight auditors and clients of smaller auditors. The results indicate that smaller firms are more likely to switch auditors after an SEC Rule 2(e) action than larger firms. Among clients of Big Eight auditors, firms with a faster rate of sales growth are more likely to switch auditors. Contrary to expectations derived from prior research, firms with audit committees are less likely to switch auditors than firms without audit committees. Among clients of smaller auditors, firms with management bonus plans tied to audited accounting data are less likely to switch auditors than firms without such compensation plans, a result opposite that predicted by agency theory. Other than the differences noted between clients of Big Eight auditors and clients of smaller auditors, the most striking result of the study is the apparent failure of agency theory to predict the response of client firms to a decline in auditor credibility
State of the College Address, 2015: College of Arts & Letters
PDF of powerpoint presentation for the Old Dominion University State of the College of Arts & Letters address on August 19, 2015
Study of research and development requirements of small gas-turbine combustors
A survey is presented of the major small-engine manufacturers and governmental users. A consensus was undertaken regarding small-combustor requirements. The results presented are based on an evaluation of the information obtained in the course of the study. The current status of small-combustor technology is reviewed. The principal problems lie in liner cooling, fuel injection, part-power performance, and ignition. Projections of future engine requirements and their effect on the combustor are discussed. The major changes anticipated are significant increases in operating pressure and temperature levels and greater capability of using heavier alternative fuels. All aspects of combustor design are affected, but the principal impact is on liner durability. An R&D plan which addresses the critical combustor needs is described. The plan consists of 15 recommended programs for achieving necessary advances in the areas of liner thermal design, primary-zone performance, fuel injection, dilution, analytical modeling, and alternative-fuel utilization
Study of an advanced transport airplane design concept known as Flatbed
The design concept and configuration of the Flatbed transport aircraft are presented. The Flatbed configuration combines into one frame, the ability to haul cargo, virtually unrestrained by cross sectional dimensions of the fuselage. The feasibility and capability of the Flatbed is discussed in depth
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