The crystal structure of dipotassium tetranitroethide

Crystal structure of dipotassium tetranitroethide determined by single crystal X-ray diffraction technique

Phase II of the ASCE Benchmark Study on SHM

The task group on structural health monitoring of the Dynamic Committee of ASCE was formed in 1999 at the 12 th Engineering Mechanics Conference. The task group has designed a number of analytical studies on a benchmark structure and there are plans to follow these with an experimental program. The first phase of the analytical studies was completed in 2001. The second phase, initiated in the summer of 2001, was formulated in the light of the experience gained on phase I and focuses on increasing realism in the simulation of the discrepancies between the actual structure and the mathematical model used in the analysis. This paper describes the rational that lead the SHM task group to the definition of phase II and presents the details of the cases that are being considered

Discipline Disproportionality of Black Students with Disabilities: Principals\u27 Perspectives

The purpose of this study is to examine the problem of practice found in discipline disproportionality of Black students with disabilities in an urban school district with a majority Black student and teacher population. Through personal interviews with building level administrators, data was gained to determine common themes that impact discipline disproportionality of Black students with disabilities. A qualitative inquiry approach, in the form of a case study was used to determine principals’ perspectives about factors that may impact discipline disproportionality. Student disciplinary records were examined to verify disproportionality and investigate patterns and categories related to students with and without disabilities being issued Office Discipline Referrals (ODRs). Interviews were conducted with building level administrators (principals and assistant principals) and their responses recorded and open coded to determine themes. Insight from this data will assist in determining what disciplinary practices may need to change and if additional and specific and professional development needs to occur for teachers and administrators

Local/State Emergency Management Relationships

Oregon is challenged with a regional liaison program that is understaffed, underfunded, and not a primary role within the Oregon Office of Emergency Management (OEM). This paper is going to examine what Oregon’s program could look like if the “regional liaison” was stand-alone position for several staff or at least a primary role within Oregon OEM. Programs from other states will be used for comparison in order to help build the picture. There are many challenges to the current program as well as creating a permanent liaison position - those will be briefly looked at. Lastly, some recommendations will be provided regarding how to overcome the challenges and what are some actions that can be taken to create an effective liaison program within Oregon OEM. Oregon currently has an ad hoc group of emergency managers stepping in to the role of a regional liaison as a side job to their already full workload

Motion of vortices in type II superconductors

The methods of formal asymptotics are used to examine the behaviour of a system of curvilinear vortices in a type II superconductor as the thickness of the vortex cores tends to zero. The vortices then appear as singularities in the field equation and are analagous to line vortices in inviscid hydrodynamics. A local analysis near each vortex core gives an equation of motion governing the evolution of these singularities

Dynamics of a deformable body in a fast flowing soap film

We study the behavior of an elastic loop embedded in a flowing soap film. This deformable loop is wetted into the film and is held fixed at a single point against the oncoming flow. We interpret this system as a two-dimensional flexible body interacting in a two-dimensional flow. This coupled fluid-structure system shows bistability, with both stationary and oscillatory states. In its stationary state, the loop remains essentially motionless and its wake is a von K\'arm\'an vortex street. In its oscillatory state, the loop sheds two vortex dipoles, or more complicated vortical structures, within each oscillation period. We find that the oscillation frequency of the loop is linearly proportional to the flow velocity, and that the measured Strouhal numbers can be separated based on wake structure

FUSE Detection of Galactic OVI Emission in the Halo above the Perseus Arm

Background observations obtained with the Far Ultraviolet Spectroscopic Explorer (FUSE) toward l=95.4, b=36.1 show OVI 1032,1038 in emission. This sight line probes a region of stronger-than-average soft X-ray emission in the direction of high-velocity cloud Complex C above a part of the disk where Halpha filaments rise into the halo. The OVI intensities, 1600+/-300 ph/s/cm^2/sr (1032A) and 800+/-300 ph/s/cm^2/sr (1038A), are the lowest detected in emission in the Milky Way to date. A second sight line nearby (l=99.3, b=43.3) also shows OVI 1032 emission, but with too low a signal-to-noise ratio to obtain reliable measurements. The measured intensities, velocities, and FWHMs of the OVI doublet and the CII* line at 1037A are consistent with a model in which the observed emission is produced in the Galactic halo by hot gas ejected by supernovae in the Perseus arm. An association of the observed gas with Complex C appears unlikely.Comment: accepted for publication in ApJL, 11 pages including 3 figure

Fast-slow asymptotic for semi-analytical ignition criteria in FitzHugh-Nagumo system

We study the problem of initiation of excitation waves in the FitzHugh-Nagumo model. Our approach follows earlier works and is based on the idea of approximating the boundary between basins of attraction of propagating waves and of the resting state as the stable manifold of a critical solution. Here, we obtain analytical expressions for the essential ingredients of the theory by singular perturbation using two small parameters, the separation of time scales of the activator and inhibitor, and the threshold in the activator's kinetics. This results in a closed analytical expression for the strength-duration curve.Comment: 10 pages, 5 figures, as accepted to Chaos on 2017/06/2