Radioactive Decay Studies of Nuclei Produced from Bombardment by Intermediate Energy Neutrons

This work was supported by National Science Foundation Grants PHY 76-84033A01, PHY 78-22774, and Indiana Universit

Search for Fission-Like Processes in the 200 MeV p+ 28-Si Reaction

This work was supported by the National Science Foundation Grant NSF PHY 81-14339 and by Indiana Universit

Gauging N=2 Supersymmetric Non-Linear σ\sigma-Models in the Atiyah-Ward Space-Time

We build up a class of N=2 supersymmetric non-linear $\sigma$-models in an N=1 superspace based on the Atiyah-Ward space-time of (2+2)-signature metric. We also discuss the gauging of isometries of the associated hyper-K\"ahlerian target spaces and present the resulting gauge-covariant supersymmetric action functional.Comment: 12 pages, latex, no figure

Sloped and Mitered Concrete Headwalls

The Kentucky Transportation Cabinet (KYTC) currently uses several pipe culvert end treatments, including standard headwalls, slope and flared headwalls, sloped and parallel headwalls, and safety metal ends. These treatments, however, can pose a safety hazard to motorists and those performing landscaping work (e.g., mowing). Crash statistics from 2012 through 2016 for Kentucky reveal that 49 fatalities and 148 incapacitating injuries occurred in incidents where culverts/headwalls were coded as the first harmful event on the police report. One solution to the safety hazards associated with standard pipe culvert headwalls is to use sloped and mitered concrete headwalls instead. To evaluate the viability of sloped and mitered concrete headwalls for widespread use, Kentucky Transportation Center (KTC) researchers reviewed industry guidance and best practices; observed, documented, and analyzed several projects on which sloped and mitered concrete headwalls were used; developed cost comparisons for sloped and mitered concrete headwalls and conventional headwalls, and evaluated specifications for sloped and mitered concrete headwalls adopted by other states. Sloped and mitered concrete headwalls conform with industry guidance and protect against significant vehicle damage. Observations of sloped and mitered concrete headwalls used on KYTC projects attested to the importance of establishing and applying unambiguous design and construction criteria. Specifically, the grade should be set before a slope and mitered headwall is installed. Furthermore, adding grate bars will improve performance as will securing pipe ends to the headwall. A sample of headwalls should be chosen for long-term monitoring purposes, with inspections conducted each year. Overall, sloped and mitered concrete headwalls are an attractive option given they can be installed quickly and without special equipment, their robust performance, and low cost compared to standard pipe culvert headwalls

Use of the MATRIXx Integrated Toolkit on the Microwave Anisotropy Probe Attitude Control System

Recent advances in analytical software tools allow the analysis, simulation, flight code, and documentation of an algorithm to be generated from a single source, all within one integrated analytical design package. NASA's Microwave Anisotropy Probe project has used one such package, Integrated Systems' MATRIXx suite, in the design of the spacecraft's Attitude Control System. The project's experience with the linear analysis, simulation, code generation, and documentation tools will be presented and compared with more traditional development tools. In particular, the quality of the flight software generated will be examined in detail. Finally, lessons learned on each of the tools will be shared

The Exclusion of Restrictive Lung Disease by Spirometric Criteria in Patients with a Reduced Forced Vital Capacity

Reductions in forced vital capacity (EVC) as determined by spirometry may result from restrictive or obstructive disease, either alone or in combination. Restrictive disease is implied when measures of forced expiratory flow are relatively maintained, and obstructive disease is present when flow measurements are disproportionately reduced. In the presence of air flow obstruction, the possibility of concomitant restrictive disease contributing to the reduction in FVC is difficult to assess from spirometry alone. Static lung volumes are usually necessary to establish this diagnosis. We evaluated the FEV1/EVC%o obtained at spirometry compared to its predicted normal value. We found it to be useful in eliminating the need for additional testing in many cases in which the question of mixed obstructive and restrictive disease had been raised. Specifically, in patients with obstructive disease and a reduced FVC, an FEV1/FVC% of less than 81%, of the age-, height-, and sex-matched predicted value largely excluded the possibility that concomitant restrictive disease was also present (p\u3c.05). Higher values had no predictive value

Polarization selection rules for inter-Landau level transitions in epitaxial graphene revealed by infrared optical Hall effect

We report on polarization selection rules of inter-Landau level transitions using reflection-type optical Hall effect measurements from 600 to 4000 cm-1 on epitaxial graphene grown by thermal decomposition of silicon carbide. We observe symmetric and anti-symmetric signatures in our data due to polarization preserving and polarization mixing inter-Landau level transitions, respectively. From field-dependent measurements we identify that transitions in decoupled graphene mono-layers are governed by polarization mixing selection rules, whereas transitions in coupled graphene mono-layers are governed by polarization preserving selection rules. The selection rules may find explanation by different coupling mechanisms of inter-Landau level transitions with free charge carrier magneto-optic plasma oscillations