Clyde Brown Oral History

Dr. Brown begins his oral history by describing the high school he attended and the extracurricular activities he was involved in. He discusses his decision to apply to and attend Denison, as well as his expectations of college. Dr. Brown describes some of the broader social and political issues when he arrived at Denison in the late 1960’s – particularly the Civil Rights Movement and protests over the Vietnam War. He addresses his initial reactions to being a Denison student, particularly with respect to the socioeconomic status of many students on campus. Dr. Brown spells out some of the organizations he was involved in at Denison, elaborates on the racial and ethnic composition of the Denison community at the time, and describes the climate for minority students. He talks about the power of the Black community at Denison and the role and effectiveness of the Black Student Union

The electronic instrumentation for atmospheric laser propagation studies

The use of laser radiation in atmospheric communication systems is revealing new forms of signal degradation not previously encountered with lower frequency transmitting sources. The coherence and directivity of the laser which is responsible for its increased signal capacity is degraded by the effect of atmospheric distortion. Random fluctuations in the index of refraction (turbulence), Rayleigh scattering, aerosol scattering and other atmospheric effects create fluctuations (boiling, breathing, dancing, attenuation, transit-time dispersion, etc.) within the beam cross section, which when received produce random fluctuations in the receiver output signal. The two systems which are described, are designed to investigate the effect of atmospheric distortions on the amplitude and phase (or transit time) of the laser beam. The Scintillation System was designed for real-time determination of amplitude scintillation statistics. The system will be incorporated into a multi-wavelength, multi-range experiment for comparison of theoretical and experimental meteorological and optical data. The system includes a laser transmitter, an atmospheric path over which the beam is allowed to diverge to a three-foot cross section, a pair of photomultipliers with variable spacing and small sampling apertures, an analog scintillation computer, and a recording device. The scintillation computer is a real time, special purpose, analog computer designed to compute the variance and covariance of log amplitude, the probability distribution of log amplitude, and the frequency spectrum of the amplitude scintillation. The system permits the recording of these data as a function of transmitter and receiver aperture, and time. The Short Pulse Distortion System is designed to detect pulse distortion due to transit-time dispersion of the laser beam. The system includes a mode-locked laser (i.e., the optical short pulse generator), a large transmitting aperture (a Cassegrainian telescope), the atmospheric path, a wideband receiver, a sampling oscilloscope, the Pulse Distortion Analyzer, and a high-quality tape recorder. The Pulse Distortion Analyzer is designed to compare the transmitted pulses to recorded reference pulses and to detect differential area due to time dispersion. The analyzer includes a novel, feed forward, automatic gain control circuit which utilizes a linear photo detector and an analog divider to smooth a 300Hz signal with a 100 microsecond response time. This is necessary to smooth out the signal amplitude fluctuations due to atmospheric turbulence effects. Both systems have been set up and tested on a one-mile path between the Oregon Graduate Center and Skyline Drive in Portland Oregon, using a 6328Å He-Ne Laser. The ultimate use of the scintillation computer will be in a multi-wave-length experiment conducted for the Office of Naval Research, and will utilize a uniform, meteorologically instrumented path for comparison with theoretical predictions. The Pulse Distortion System will be incorporated into a joint experiment with the Electro-optic Organization of Sylvania Electronic Systems, Inc., Mountain View, California, to be conducted over a seven-mile path

Carbonic Anhydrase in Certain Species of Plants

Author Institution: Charles F. Kettering Foundation, Yellow Springs, Ohi

The Photosynthetic Function of Manganese and Chloride

Author Institution: Charles F. Kettering Foundation, Yellow Springs, Ohi

An Overview of Measurement Comparisons from the INTEX-B/MILAGRO Airborne Field Campaign

As part of the NASA's INTEX-B mission, the NASA DC-8 and NSF C-130 conducted three wing-tip to wing-tip comparison flights. The intercomparison flights sampled a variety of atmospheric conditions (polluted urban, non-polluted, marine boundary layer, clean and polluted free troposphere). These comparisons form a basis to establish data consistency, but also should also be viewed as a continuation of efforts aiming to better understand and reduce measurement differences as identified in earlier field intercomparison exercises. This paper provides a comprehensive overview of 140 intercomparisons of data collected as well as a record of the measurement consistency demonstrated during INTEX-B. It is the primary goal to provide necessary information for the future research to determine if the observations from different INTEX-B platforms/instrument are consistent within the PI reported uncertainties and used in integrated analysis. This paper may also contribute to the formulation strategy for future instrument developments. For interpretation and most effective use of these results, the reader is strongly urged to consult with the instrument principle investigator

The Design and Role of a Low Cost Semi-Automated Mobile Ground Station in the Tracking and Commanding of Low Earth Orbit Satellites

The traditional ground station consists of a building full of specialized hardware and a large stationary antenna operated by a group of on-site personnel. Reduced budgets have forced project managers to re-evaluate this concept in search of ways to save money. To this end, PC-based systems have been developed that reduce hardware costs and the number of machines and personne I necessary to perform station tasks. In this paper, we will take this concept to the next level. By improving on the current PC-based systems we will further reduce the hardware and personnel costs, and by introducing the concept of a mobile ground station for low earth orbit (LEO) satellites we will reduce real estate costs while conceivably reducing the number of ground stations required. Together these ideas form the basis for the future of low cost ground station support

Decision Support Methods and Tools

This paper is one of a set of papers, developed simultaneously and presented within a single conference session, that are intended to highlight systems analysis and design capabilities within the Systems Analysis and Concepts Directorate (SACD) of the National Aeronautics and Space Administration (NASA) Langley Research Center (LaRC). This paper focuses on the specific capabilities of uncertainty/risk analysis, quantification, propagation, decomposition, and management, robust/reliability design methods, and extensions of these capabilities into decision analysis methods within SACD. These disciplines are discussed together herein under the name of Decision Support Methods and Tools. Several examples are discussed which highlight the application of these methods within current or recent aerospace research at the NASA LaRC. Where applicable, commercially available, or government developed software tools are also discusse