Apparatus for applying simulator g-forces to an arm of an aircraft simulator pilot

A device to be used with an aircraft simulator to apply positive and negative g forces to the pilot's arm is described. An arm harness fits around the arm which the pilot uses to operate the throttle. The device allows the harness to track intentional arm movements without exerting any restraining forces, and at the same time, applies g forces to to the pilots arm which are recorded by the aircraft simulator computer

Dynamic analysis of a photovoltaic power system with battery storage capability

A photovolataic power system with a battery storage capability is analyzed. A dual battery current control concept is proposed, which enables the battery to either supply or accept power depending upon system environment and load conditions. A simulation of the power system, including the battery current control, is developed and evaluated. The evaulation demonstrate the visbility of the battery control concept of switch the battery from a charge to discharge mode and back as required by load and environmental conditions. An acceptable system operation is demonstrated over the entire insolation range. Additionally, system sensitivity, bandwidth, and damping characteristics of the battery control are shown to be acceptable for a projected hardware implementation

Integrated Optimization of Mars Hybrid Solar-Electric/Chemical Propulsion Trajectories

NASAs Human Exploration and Operation Mission Directorate is developing a reusable hybrid transportation architecture in which both chemical and solar-electric propulsion systems are used to deliver crew and cargo to the Martian sphere of influence. By combining chemical and solar-electric propulsions into a single spacecraft and applying each where it is the most effective, the hybrid architecture enables a series of Mars trajectories that are more fuel efficient than an all chemical propulsion architecture without significant increase to trip time. Solving the complex problem of low-thrust trajectory optimization coupled with the vehicle sizing requires development of an integrated trajectory analysis frame- work. Previous studies have utilized a more segmented optimization framework due to the limitation of the tools available. A new integrated optimization framework was recently developed to address the deficiencies of the previous methods that enables higher fidelity analysis to be performed and increases the efficiency of large design space explorations

An inverter/controller subsystem optimized for photovoltaic applications

Conversion of solar array dc power to ac power stimulated the specification, design, and simulation testing of an inverter/controller subsystem tailored to the photovoltaic power source characteristics. Optimization of the inverter/controller design is discussed as part of an overall photovoltaic power system designed for maximum energy extraction from the solar array. The special design requirements for the inverter/ controller include: a power system controller (PSC) to control continuously the solar array operating point at the maximum power level based on variable solar insolation and cell temperatures; and an inverter designed for high efficiency at rated load and low losses at light loadings to conserve energy

Interaction of H_2 and O_2 on platinum (111)

Abstract Unavailabl

The Latter Day Saint Press, 1830-1930

thesisDuring the one hundred years that have elapsed since the Church of Jesus Christ of Latter Day Saints was organized in Fayette, Seneca County, New York, on April 6, 1830, more than fifty newspapers and magazines at various times have been fostered by the organization. Many of these periodicals have had a mushroom growth. They have sprung up, blossomed for a season and then have died away. Only a few have continued throughout the years

Growth of the Higher Educational Institutions for Negroes Accredited Class A 1931-1941

This investigation briefly traces the growth and development of Negro Higher Institutions of Learning which have been accredited class A since 1931 by the following associations: the North Central Association of Colleges and Secondary Schools, the Middle States Association of Colleges and Secondary Schools, and the Southern States Association of Colleges and Secondary Schools. The beginning portion of the work sketches the problems confronting the Negro following his liberation and discusses the pioneer organizations that have assisted him in securing and establishing the schools that he now exclusively enjoys. The study differentiates the privately supported school from the publicly supported school and tells when the institutions were founded and where they are located. It lists the particular types of training that each school offers and mentions the kinds of degree conferred. No predictions are made as to what the future holds for these schools. Data that proved especially helpful were gathered through the use of questionnaires and bulletins received from the various colleges