Two-dimensional hydrodynamic simulations of mass transfer in short-period Algol-type binaries were performed using the numerical code Virginia Hydrodynamics 1. This code uses the piecewise parabolic method with a Lagrangian remap. Our version of the code also accounts for radiative cooling and collisional ionization and excitation processes. The purpose of performing the simulations was to study the Ha emission from circumstellar gas in the Algols. Using observational evidence from the literature to constrain the gas stream properties, hydrodynamic maps of the Ha emissivity in the two systems b Per (P \ 2.87 days) and TT Hya (P \ 6.95 days) were made in both Cartesian and velocity coordinates from the simulation data. The velocity maps were then compared to Doppler tomograms constructed from observed Ha line emission in these systems. Since the tomograms cannot be directly transformed to maps of emission in spatial coordinates, the simulated Cartesian maps enabled us to interpret the dynamical processes that produce the features observed in the Doppler tomograms. We Ðnd that the simulations produce asymmetric accretion structures with many features similar to those found in the Doppler tomograms of Algol systems.

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Two-dimensional hydrodynamical simulations of mass transfer in short period Algol type binaries were performed using the numerical code VH−1. This code uses the Piecewise Parabolic Method with a Lagrangian Remap. Our version of the code also accounts for radiative cooling processes. The purpose of performing the simulations was to study the Hα emission from circumstellar gas in the Algols. Using observational evidence from the literature to constrain the gas stream properties, hydrodynamical maps of the Hα emissivity in the two systems β Per (P = 2.87d) and TT Hya (P = 6.95d) were made in both Cartesian and velocity coordinates from the simulation data. The velocity maps were then compared to Doppler tomograms constructed from observed Hα line emission in these systems. Since the tomograms cannot be directly transformed to maps of emission in spatial coordinates, the simulated Cartesian maps enable us to interpret the dynamical processes which produce the features observed in the Doppler tomograms. We find that the simulations produce asymmetric accretion structures with many features similar to those found in the Doppler tomograms of Algol systems.

This mixed-methods study examines the perceptions of classified and certified staff members at a rural, Southwestern Ohio high school and was based on results from a 27-item questionnaire. The study covered three main topics: (1) perceptions of safety, (2) perceptions of armed employees, and (3) views on what procedures and limitations should be in place if a school were to adopt an armed employee policy. With results similar to previous nationwide surveys, 94.4% of participants believed their school is a safe place to work, however only 66.7% believed their school has sufficient procedures in place should a school shooting occur. Also the results indicated that 38.8% of participants would be willing to carry a concealed weapon on school grounds, 30.6% would not be willing to carry a concealed weapon, and 30.6% were unsure. While many of the participants believed that there is a need to fight back, they also raised concerns regarding teachers carrying concealed weapons such as: weapon security, training, and mental health stability. The results showed a significant difference between the perceptions of certified and classified staff in the following areas: (1) the sufficiency of current procedures; (2) having multiple teachers carry concealed weapons; and, (3) having multiple administrators carry concealed weapons. The research also indicated the need for schools to critically examine, discuss, and practice the procedures that are already in place in order to ensure that the current procedures are sufficient should an active shooting occur.