4,674 research outputs found

    Development of the command data system and ground software for the SEDSAT-1 microsatellite

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    SEDSAT-1 is designed to be a low cost scientific satellite which is to be used to perform a minimum of five tasks which include: (1) the acquisition of a number of important parameters associated with the tethering processes from the payloads perspective (such as accelerations incurred and imaging data of the tether during deployment), (2) to act as a remote sensing platform for making measurements of the Earth's Atmosphere (allowing research to be performed in such areas as vertical lightning observation, visible light spectrography, and cloud cover studies, (3) to act as a general purpose amateur radio communication satellite relaying information back to earth, (4) to demonstrate the feasibility of the deployment in low earth orbit of advanced technology such as the Gallium Arsenide Solar Cells, Nickel Metal Hydride batteries, and multi-chip module technology and, (5) to support student's active participation in applying the disciplines of engineering and science to space-based hardware platforms. The project includes the Three-axis Accelerometer System, TAS, Experiment which is designed to report the accelerations that the satellite undergoes during the tethering operations and during the second phase of the mission when the free floating satellite comes in contact with orbit debris. The SEASIS (SEDS Earth, Atmosphere, and Space Imaging System) is another SEDSAT experiment designed to provide images of the tether during its deployment and the earth during the second phase of the mission. To control these experiments and virtually all other satellite operations the Command Data System, CDS is employed. This system utilizes a moderate complexity micro-controller controlled by tasks operating under a real-time operating system to dynamically monitor and control the satellite. The scope of this researchers efforts has been in the general area of coordinating and assisting the student researchers with the development of the CDS and ground station interfaces. This included the low level CDS hardware design and the formulization of a general software plan and schedule for both the CDS and ground station portions of the project

    ECONOMIC BENEFITS OF CRITICAL HABITAT FOR THE MEXICAN SPOTTED OWL: A SCOPE TEST USING A MULTIPLE-BOUNDED CONTINGENT VALUATION SURVEY

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    A split-sample design is used to test for a difference between mean willingness to pay (WTP) for protecting the Mexican spotted owl versus protecting 62 threatened/endangered species which includes the Mexican spotted owl. The multiple bounded contingent valuation method is used in a mail survey of U.S. residents. The mean WTP amounts are statistically different at the 0.1 confidence level indicating the multiple-bounded mail survey passes the scope test. The range of estimated benefits of preserving the 4.6 million acres of critical habitat for the Mexican spotted owl substantially outweighs the costs of the recovery effort.Environmental Economics and Policy,

    Business Profitability and Social Profitability: Evaluating Industries with Externalities, The Case Casinos.

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    Casino gambling is a social issue, because in addition to the direct benefits to those who own and use casinos, positive and negative externalities are reaped and borne by those who do not gamble. To correctly assess the total economic impact of casinos, one must distinguish between business profitability and social profitability. This paper provides the most comprehensive framework for addressing the theoretical cost–benefit issues of casinos by grounding cost–benefit analysis on household utility. It also discusses the current state of knowledge about the estimates of both the positive and negative externalities generated by casinos. Lastly, it corrects many prevalent errors in the debate over the economics of casino gambling.casino, crime, gambling, social costs, externality

    Species Composition and Diversity of Hawk Populations in Northeastern Arkansas

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    Species composition and diversity of hawk populations were analyzed for northeastern Arkansas by the use of roadside censuses conducted in September through April from 1974- 1977. Data from 10 years of Jonesboro Christmas Bird Counts were also analyzed. During the roadside survey 20,174 miles were driven and 1819 raptors were counted. Ten species were observed with the Red-tailed Hawk being most abundant followed by the Marsh Hawk and the American Kestrel. Eight species were recorded from the 10 years of Christmas Bird Counts. Annual breeding bird surveys and spot records turned up three additional species making a total of 14 species in 15 years of study. Although hawk populations fluctuate from year to year, the data do not reveal any downward trend in numbers in northeastern Arkansas. Large concentrations of hawks do not appear in this region of the state until after mid-September. Populations reach a peak in December after which they decline in January. A second peak is reached in February followed by a gradual decline such that in April the American Kestrel is the only species consistently seen from the roadside. After April only a few hawks remain to nest. Both Krider\u27s and melanistic Red-tails occur here but from a total of 864 Red-tailed Hawks observed only 26 Krider\u27s and 31 melanistic or Buteo iamaicensis harlanii were recorded

    The dynamical transition in proteins and non-Gaussian behavior of low frequency modes in Self Consistent Normal Mode Analysis

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    Self Consistent Normal Mode Analysis (SCNMA) is applied to heme c type cytochrome f to study temperature dependent protein motion. Classical Normal Mode Analysis (NMA) assumes harmonic behavior and the protein Mean Square Displacement (MSD) has a linear dependence on temperature. This is only consistent with low temperature experimental results. To connect the protein vibrational motions between low temperature and physiological temperature, we have incorporated a fitted set of anharmonic potentials into SCNMA. In addition, Quantum Harmonic Oscillator (QHO) theory has been used to calculate the displacement distribution for individual vibrational modes. We find that the modes involving soft bonds exhibit significant non-Gaussian dynamics at physiological temperature, which suggests it may be the cause of the non-Gaussian behavior of the protein motions probed by Elastic Incoherent Neutron Scattering (EINS). The combined theory displays a dynamical transition caused by the softening of few "torsional" modes in the low frequency regime (< 50cm-1or 0.6ps). These modes change from Gaussian to a classical distribution upon heating. Our theory provides an alternative way to understand the microscopic origin of the protein dynamical transition.Comment: 17 pages, 6 figures, 1 tabl

    Stage Construction As It Applies to Indiana Roads

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    Irregation Automation: A Systems Approach

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    This thesis defines areas in which the electrical engineer can assist in developing irrigation automation. Particular attention is given to a telemetry system for data transmission from soil moisture sensors. Present and future communication requirements in automated irrigation systems are also discussed
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