1,639 research outputs found

    Differences Associated with Mating Type Alleles in Myxomycetes

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    Differences associated with the mating type alleles of Didymium iridis and Physarum polycephalum were examined with fluorescent antibody and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Heteroabsorption of each anti-myxamoebal serum followed by testing serum activity using immunofluorescence showed there is no strain-specific activity in any of the anti-myxamoebal sera, but the sera was shown, to be genera specific. Intergeneric differences and similarities were shown in the electrophoretic patterns of the myxamoebal protein extracts from P. polycephalum, D. iridis, and Dictyostelium discoideum when compared. Intraspecific differences were noted in D. iridis

    Delia Peets: A Montana Suffragist

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    I will explore the role of Delia Peets, a resident of Butte, Montana, in women’s organizations in the area from the 1890’s to 1930. I conducted research in federal census records, Montana city directories, Silver Bow County marriage records, records from the Montana State Historical Society, local newspapers, books, journals of the Grand Army of the Republic, journals from the National Convention of the Women’s Relief Corps, and Archives and Special Collections at Mansfield Library. My research on Delia Peets focuses on her extensive involvement in various women’s clubs in Montana and their effect on the suffrage movement, particularly until Montana women were given the right to vote in 1914. These include prominent organizations such as the Women’s Relief Corps and the Consumer’s League, both of which had connections to the movement nationally. This brings attention to not only Delia Peets herself, but to the women involved in these Montana organizations and their influence overall in the state. A focus on lesser know Montana activists is essential for a deeper understanding of the suffrage movement in the state, and women’s history as a whole

    Limit Cycle Analysis Applied to the Oscillations of Decelerating Blunt-Body Entry Vehicles

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    Many blunt-body entry vehicles have nonlinear dynamic stability characteristics that produce self-limiting oscillations in flight. Several different test techniques can be used to extract dynamic aerodynamic coefficients to predict this oscillatory behavior for planetary entry mission design and analysis. Most of these test techniques impose boundary conditions that alter the oscillatory behavior from that seen in flight. Three sets of test conditions, representing three commonly used test techniques, are presented to highlight these effects. Analytical solutions to the constant-coefficient planar equations-of-motion for each case are developed to show how the same blunt body behaves differently depending on the imposed test conditions. The energy equation is applied to further illustrate the governing dynamics. Then, the mean value theorem is applied to the energy rate equation to find the effective damping for an example blunt body with nonlinear, self-limiting dynamic characteristics. This approach is used to predict constant-energy oscillatory behavior and the equilibrium oscillation amplitudes for the various test conditions. These predictions are verified with planar simulations. The analysis presented provides an overview of dynamic stability test techniques and illustrates the effects of dynamic stability, static aerodynamics and test conditions on observed dynamic motions. It is proposed that these effects may be leveraged to develop new test techniques and refine test matrices in future tests to better define the nonlinear functional forms of blunt body dynamic stability curves

    Eliciting a directed acyclic graph for a multivariate time series of vehicle counts in a traffic network

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    The problem of modelling multivariate time series of vehicle counts in traffic networks is considered. It is proposed to use a model called the linear multiregression dynamic model (LMDM). The LMDM is a multivariate Bayesian dynamic model which uses any conditional independence and causal structure across the time series to break down the complex multivariate model into simpler univariate dynamic linear models. The conditional independence and causal structure in the time series can be represented by a directed acyclic graph (DAG). The DAG not only gives a useful pictorial representation of the multivariate structure, but it is also used to build the LMDM. Therefore, eliciting a DAG which gives a realistic representation of the series is a crucial part of the modelling process. A DAG is elicited for the multivariate time series of hourly vehicle counts at the junction of three major roads in the UK. A flow diagram is introduced to give a pictorial representation of the possible vehicle routes through the network. It is shown how this flow diagram, together with a map of the network, can suggest a DAG for the time series suitable for use with an LMDM

    Sitting in the Pilot's Seat; Optimizing Human-Systems Interfaces for Unmanned Aerial Vehicles

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    One of the pilot-machine interfaces (the forward viewing camera display) for an Unmanned Aerial Vehicle called the DROID (Dryden Remotely Operated Integrated Drone) will be analyzed for optimization. The goal is to create a visual display for the pilot that as closely resembles an out-the-window view as possible. There are currently no standard guidelines for designing pilot-machine interfaces for UAVs. Typically, UAV camera views have a narrow field, which limits the situational awareness (SA) of the pilot. Also, at this time, pilot-UAV interfaces often use displays that have a diagonal length of around 20". Using a small display may result in a distorted and disproportional view for UAV pilots. Making use of a larger display and a camera lens with a wider field of view may minimize the occurrences of pilot error associated with the inability to see "out the window" as in a manned airplane. It is predicted that the pilot will have a less distorted view of the DROID s surroundings, quicker response times and more stable vehicle control. If the experimental results validate this concept, other UAV pilot-machine interfaces will be improved with this design methodology

    Infrared observations of the outer solar corona

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    Infrared observations of outer solar corona at wavelength of 22 micron

    Valuing Historical and Open Space Amenities with Hedonic Property Valuation Models

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    Impacts of historic and cultural amenities on property values and the economy have not been widely studied in part because of problems isolating statistical effects using nonmarket valuation and lack of study areas. Three jurisdictions in Virginia containing major historic sites provide a unique setting in which to isolate the effects of historical amenities on residential property values using revealed preferences and quantify their economic benefits. We find that historic areas provide both open space and historic amenities. Furthermore, being adjacent to a historical area is not a positive benefit on average, perhaps because of activity and congestion associated with tourism. Residing close to such areas is valuable to buyers

    Oscillation Amplitude Growth for a Decelerating Object with Constant Pitch Damping

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    The equations governing the deceleration and oscillation of a blunt body moving along a planar trajectory are re-expressed in the form of the Euler-Cauchy equation. An analytic solution of this equation describes the oscillation amplitude growth and frequency dilation with time for a statically stable decelerating body with constant pitch damping. The oscillation histories for several constant pitch damping values, predicted by the solution of the Euler-Cauchy equation are compared to POST six degree-of-freedom (6-DoF) trajectory simulations. The simulations use simplified aerodynamic coefficients matching the Euler-Cauchy approximations. Agreement between the model predictions and simulation results are excellent. Euler-Cauchy curves are also fit through nonlinear 6-DoF simulations and ballistic range data to identify static stability and pitch damping coefficients. The model os shown to closely fit through the data points and capture the behavior of the blunt body observed in simulation and experiment. The extracted coefficients are in reasonable agreement with higher fidelity, nonlinear parameter identification results. Finally, a nondimensional version of the Euler-Cauchy equation is presented and shown to be a simple and effective tool for designing dynamically scaled experiments for decelerating blunt capsule flight

    Adolescents care but don't feel responsible for farm animal welfare

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    Adolescents are the next generation of consumers with the potential to raise standards of farm animal welfare—to theirsatisfaction—if their preferences and concerns are translated into accurate market drivers and signals. There are no published data about adolescent views of farm animal welfare to allow meaningful design, implementation, and evaluation of educational strategies to improve consideration of—and behavior toward—farm animals. Knowledge of farm animal welfare, as well as beliefs and attitudes about farm animal welfare and behavioral intention relevant to it were determined in a sample of ukadolescents, using a survey incorporating an extended version of the theory of planned behavior and novel assessment tools. Our results indicate that adolescents have only a limited knowledge of welfare problems for farm animals and welfare-relevant product labels. Intentions to identify welfare standards for the animals from whom their food was derived were weak. Although they cared about farm animal welfare and agreed with fundamental principles—for example, the provision of space and the absence of pain and suffering—like adults they held limited belief in the power and responsibility that they possess through their choices as consumers; responsibility was often shifted to others, such as the government and farmers

    ASPIRE Flight Mechanics Modeling and Post Flight Analysis

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    The Advanced Supersonic Parachute Inflation Research and Experiment (ASPIRE) is a series of sounding rocket flights aimed at understanding the dynamics of supersonic parachutes that are used for Mars robotic applications. SR01 was the first sounding rocket flight of ASPIRE that occurred off the coast of Wallops Island, VA on Oct. 4, 2017 and showed the successful deployment and inflation of a Mars Science Laboratory built-to- print parachute in flight conditions similar to the 2012 Mars Science Laboratory (MSL) mission. SR02 was the second sounding rocket flight that also occurred off the coast of Wallops Island on March 31, 2018 and showcased the successful deployment and inflation of a new strengthened parachute being considered for the Mars 2020 mission at fifty percent higher dynamic pressure than observed on MSL. Prior to both flights, a multi-body flight dynamics simulation was developed to predict the parachute dynamics and was used, in conjunction with other tools, to target Mars-relevant flight conditions. After each flight, the reconstructed trajectory was used to validate the pre-flight dynamics simulation and recommend changes to improve predictions for future flights planned for the ASPIRE pro- gram. This paper describes the flight mechanics simulation and the post flight reconciliation process used to validate the flight models
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