1,208 research outputs found

    Orbiter Flying Qualities (OFQ) Workstation user's guide

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    This project was devoted to the development of a software package, called the Orbiter Flying Qualities (OFQ) Workstation, for working with the OFQ Archives which are specially selected sets of space shuttle entry flight data relevant to flight control and flying qualities. The basic approach to creation of the workstation software was to federate and extend commercial software products to create a low cost package that operates on personal computers. Provision was made to link the workstation to large computers, but the OFQ Archive files were also converted to personal computer diskettes and can be stored on workstation hard disk drives. The primary element of the workstation developed in the project is the Interactive Data Handler (IDH) which allows the user to select data subsets from the archives and pass them to specialized analysis programs. The IDH was developed as an application in a relational database management system product. The specialized analysis programs linked to the workstation include a spreadsheet program, FREDA for spectral analysis, MFP for frequency domain system identification, and NIPIP for pilot-vehicle system parameter identification. The workstation also includes capability for ensemble analysis over groups of missions

    The Constitutionality of the Oklahoma Surface Damages Act

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    Manual control of unstable systems

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    Under certain operational regimes and failure modes, air and ground vehicles can present the human operator with a dynamically unstable or divergent control task. Research conducted over the last two decades has explored the ability of the human operator to control unstable systems under a variety of circumstances. Past research is reviewed and human operator control capabilities are summarized. A current example of automobile directional control under rear brake lockup conditions is also reviewed. A control system model analysis of the driver's steering control task is summarized, based on a generic driver/vehicle model presented at last year's Annual Manual. Results from closed course braking tests are presented that confirm the difficulty the average driver has in controlling the unstable directional dynamics arising from rear wheel lockup

    Insulator - Insulator Contact Charging as a Function of Pressure

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    Metal - metal and metal - insulator contact or triboelectric charging are well known phenomena with good theoretical understanding of the charge exchange mechanism. However, insulator - insulator charging is not as well understood. Theoretical and experimental research has been performed that shows that the surface charge on an insulator after triboelectric charging with another insulator is rapidly dissipated with lowered atmospheric pressure. This pressure discharge is consistent with surface ions being evaporated off the surface once their vapor pressure is attained. A two-phase equilibrium model based on an ideal gas of singly charged ions in equilibrium with a submonolayer adsorbed film was developed to describe the pressure dependence of the surface charge on an insulator. The resulting charge density equation is an electrostatic version of the Langmuir isotherm

    The influence of rifle carriage on the kinetics of human gait

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    The influence that rifle carriage has on human gait has received little attention in the published literature. Rifle carriage has two main effects, to add load to the anterior of the body and to restrict natural arm swing patterns. Kinetic data were collected from 15 male participants, with 10 trials in each of four experimental conditions. The conditions were: walking without a load (used as a control condition); carrying a lightweight rifle simulator, which restricted arm movements but applied no additional load; wearing a 4.4 kg diving belt, which allowed arms to move freely; carrying a weighted (4.4 kg) replica SA80 rifle. Walking speed was fixed at 1.5 m/s (+5%) and data were sampled at 400 Hz. Results showed that rifle carriage significantly alters the ground reaction forces produced during walking, the most important effects being an increase in the impact peak and mediolateral forces. This study suggests that these effects are due to the increased range of motion of the body’s centre of mass caused by the impeding of natural arm swing patterns. The subsequent effect on the potential development of injuries in rifle carriers is unknown

    Triboelectric, Corona, and Induction Charging of Insulators as a Function of Pressure

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    Theoretical and experimental research has been performed that shows that the surface charge on an insulator after triboelectric charging with another insulator is rapidly dissipated with lowered atmospheric pressure. This pressure discharge is consistent with surface ions being evaporated off the surface once their vapor pressure is attained. In this paper we will report on the results of three different charging techniques (triboelectric, corona, and induction) performed on selected polymers with varying atmospheric pressure. This data will show that ion exchange between the polymer samples is the mechanism responsible for most of the surface charge on the polymer surfaces

    Martyrdom and self-sacrifice in the Catholic novels of Graham Greene

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    The religious acts of self-sacrifice and martyrdom, rarely identified or discussed in works of criticism on Graham Greene's fiction, play a significant role both as a central theme and as a climactic action in his Catholic novels. Greene utilizes these sacrificial acts as the means to reveal the complex and often paradoxical nature of his characters in their relationship to God and to men. In his pre-Vatican II novels, Brighton Rock, The Power and the Glory, The Heart of the Matter and The End of the Affair, and in his post-Vatican II novels. The Honorary Consul and Monsignor Quixote, the challenging demands of the call to self-sacrifice and martyrdom not only represent a key religious theme but also shape the essential dramatic conflict in the crisis of faith that ensnares his characters. It is precisely from the personal decision to accept or reject the call to perform the acts of self-sacrifice and martyrdom that Greene's characters evolve and his narratives attain their metaphysical dimension. The unique response of each character to this call of grace to self-sacrifice becomes the climactic act of his or her human experience of faith as well as the action that unifies all of Greene's themes concerning the predicament of mankind in a fallen world. This thesis analyses both the personal response of the characters as it is conditioned by their particular situations, and the recurring elements of vocation, freedom, love and the imitation of Christ that become apparent in each case
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