271 research outputs found

    Daily Activity Patterns Among Apex Predators in the Northwest United States

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    The gray wolf [Canis lupus], brown bear [Ursus arctos], and American black bear [Ursus americanus], are all ecologically interesting because they are all apex predators that exist in the same spaces in the United States. However, little research has been done after wolf reintroduction in many parts of the western U.S. to see if these three predators will change their daily activity patterns around each other. The goal of this research project was to see whether the daily activity patterns of the gray wolf, brown bear, and American black bear differ, and it was hypothesized that he American black bear and brown bear will be more active during the day while the gray wolf will be more active at night. Bar graphs of the daily activity pattern of each species was created using occurrences in camera trap images from Snapshot USA. Overall, the observed daily activity patterns show that the American black bear and brown bear followed a crepuscular activity pattern and the gray wolf followed a nocturnal activity pattern. Knowing these daily activity patterns can help mitigate human-wildlife conflict in spaces where they interact, which is especially important for the gray wolf since it is endangered, and future research could look into the cause of the activity patterns of the gray wolf, brown bear, and American black bear, whether it be due to competition among each other, with other species, or with humans

    A Numerical Study of Methods for Moist Atmospheric Flows: Compressible Equations

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    We investigate two common numerical techniques for integrating reversible moist processes in atmospheric flows in the context of solving the fully compressible Euler equations. The first is a one-step, coupled technique based on using appropriate invariant variables such that terms resulting from phase change are eliminated in the governing equations. In the second approach, which is a two-step scheme, separate transport equations for liquid water and vapor water are used, and no conversion between water vapor and liquid water is allowed in the first step, while in the second step a saturation adjustment procedure is performed that correctly allocates the water into its two phases based on the Clausius-Clapeyron formula. The numerical techniques we describe are first validated by comparing to a well-established benchmark problem. Particular attention is then paid to the effect of changing the time scale at which the moist variables are adjusted to the saturation requirements in two different variations of the two-step scheme. This study is motivated by the fact that when acoustic modes are integrated separately in time (neglecting phase change related phenomena), or when sound-proof equations are integrated, the time scale for imposing saturation adjustment is typically much larger than the numerical one related to the acoustics

    Developing a Quality Control Protocol for Evaluation of Recorded Interviews

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    This presentation will describe the process used at the University of Michigan Survey Research Center for evaluating interviewer performance in survey administration. Within the Survey Research Operations unit, we use an online system for evaluating the interviewer-respondent interaction using recorded interviews. We will present our framework for measuring how well interviewers adhere to General Interviewing Techniques (GIT) - the guidelines in which they were trained. The presentation will describe the question-level and session-level measurement criteria employed, in addition to the selection protocols and the integration of paradata into the selection process. The presentation will include analysis of some evaluation data, with a discussion of how the data were used to inform further development of the evaluation protocol. Although some aggregate data will be shared, the presentation will largely focus on the operational considerations related to the development and implementation of the quality control protocol across projects

    Developing a Quality Control Protocol for Evaluation of Recorded Interviews

    Get PDF
    This presentation will describe the process used at the University of Michigan Survey Research Center for evaluating interviewer performance in survey administration. Within the Survey Research Operations unit, we use an online system for evaluating the interviewer-respondent interaction using recorded interviews. We will present our framework for measuring how well interviewers adhere to General Interviewing Techniques (GIT) - the guidelines in which they were trained. The presentation will describe the question-level and session-level measurement criteria employed, in addition to the selection protocols and the integration of paradata into the selection process. The presentation will include analysis of some evaluation data, with a discussion of how the data were used to inform further development of the evaluation protocol. Although some aggregate data will be shared, the presentation will largely focus on the operational considerations related to the development and implementation of the quality control protocol across projects

    Increases in moist-convective updraught velocities with warming in radiative-convective equilibrium

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    The scaling of updraught velocities over a wide range of surface temperatures is investigated in simulations of radiative-convective equilibrium with a cloud-system resolving model. The updraught velocities increase with warming, with the largest fractional increases occurring in the upper troposphere and for the highest percentile updraughts. A plume model approximately reproduces the increases in updraught velocities if the plume environment is prescribed as the mean profile in each simulation while holding the entrainment and microphysical assumptions fixed. Convective available potential energy (CAPE) also increases with warming in the simulations but at a much faster fractional rate when compared with the square of the updraught velocities. This discrepancy is investigated with a two-plume model in which a weakly entraining plume represents the most intense updraughts, and the environment is assumed to adjust so that a more strongly entraining plume has negligible buoyancy. The two-plume model suggests that updraught velocities increase with warming at a lower fractional rate than implied by the CAPE because of the influence of entrainment on both the mean stratification and the updraughts themselves.National Science Foundation (U.S.) (grant AGS-1148594)United States. National Aeronautics and Space Administration. Research Opportunities in Earth and Space Science (grant 09-IDS09-0049
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