Computations of unsteady multistage compressor flows in a workstation environment

High-end graphics workstations are becoming a necessary tool in the computational fluid dynamics environment. In addition to their graphic capabilities, workstations of the latest generation have powerful floating-point-operation capabilities. As workstations become common, they could provide valuable computing time for such applications as turbomachinery flow calculations. This report discusses the issues involved in implementing an unsteady, viscous multistage-turbomachinery code (STAGE-2) on workstations. It then describes work in which the workstation version of STAGE-2 was used to study the effects of axial-gap spacing on the time-averaged and unsteady flow within a 2 1/2-stage compressor. The results included time-averaged surface pressures, time-averaged pressure contours, standard deviation of pressure contours, pressure amplitudes, and force polar plots

Maps on 3-manifolds given by surgery

Suppose that the 3-manifold M is given by integral surgery along a link L in S^3. In the following we construct a stable map from M to the plane, whose singular set is canonically oriented. We obtain upper bounds for the minimal numbers of crossings and non-simple singularities and of connected components of fibers of stable maps from M to the plane in terms of properties of L.Comment: 22 pages, 13 figures. Accepted for publication by Pacific J. Mat

Validation and Verification of LADEE Models and Software

The Lunar Atmosphere Dust Environment Explorer (LADEE) mission will orbit the moon in order to measure the density, composition and time variability of the lunar dust environment. The ground-side and onboard flight software for the mission is being developed using a Model-Based Software methodology. In this technique, models of the spacecraft and flight software are developed in a graphical dynamics modeling package. Flight Software requirements are prototyped and refined using the simulated models. After the model is shown to work as desired in this simulation framework, C-code software is automatically generated from the models. The generated software is then tested in real time Processor-in-the-Loop and Hardware-in-the-Loop test beds. Travelling Road Show test beds were used for early integration tests with payloads and other subsystems. Traditional techniques for verifying computational sciences models are used to characterize the spacecraft simulation. A lightweight set of formal methods analysis, static analysis, formal inspection and code coverage analyses are utilized to further reduce defects in the onboard flight software artifacts. These techniques are applied early and often in the development process, iteratively increasing the capabilities of the software and the fidelity of the vehicle models and test beds

Cyberbullying Prevention and Intervention: Perspectives of School Psychologists and School Counselors

Recent studies have found that increasing numbers of students are experiencing cyberbullying during middle and high school. The current study examined how school psychologists and school counselors are involved in the prevention and intervention of cyberbullying as well as what practices their schools are implementing to address this issue. Results found that school counselors were more involved than school psychologists with cyberbullying prevention and intervention efforts. However, 50% of school psychologists felt that their skills were being underutilized and 59% expressed a desire to be more involved in cyberbullying prevention and intervention efforts. Receiving training on cyberbullying was found to be related to increased feelings of preparedness to be involved with cyberbullying prevention and intervention. Though, in this study, only 8% of all participants felt very prepared to help select cyberbullying prevention and intervention programs. Participants rated creating a cyberbullying taskforce, positive school climate programs, peer mentors, and teaching empathy as the most effective prevention and intervention strategies. Based on these findings, schools need to provide the staff more training on the issue of cyberbullying and develop strategies to reduce school psychologists’ barriers to involvement in this area. This will allow schools to develop knowledgeable teams to help address the issue of cyberbullying prevention and intervention

The Use of Standards on the LADEE Mission

The Lunar Atmosphere Dust Environment Explorer (LADEE) was a small explorer class mission that launched Sept 7, 2013 and successfully de-orbited and impacted the moon's surface on April 17, 2014. The spacecraft was the first to launch from a Minotaur 5 and was the first deep space mission to launch from the Wallops flight facility. Figure 1 shows the famous image of a frog unlucky enough to be launched from the facility at the same time as LADEE. The science mission for the spacecraft was to determine the density, composition and variability of the lunar exosphere. In addition, it performed a first-of-a-kind demonstration of laser-based communications from deep space that exhibited a record downlink rate of 622 megabits per second from the moon. In order to perform the lunar dust surveys, the spacecraft was placed in a retrograde equatorial orbit with periapsis between 20 and 60 kilometers. The mission was granted an extension in which final science surveys were performed at altitudes as low as 2 kilometers over the moon's surface. The cadence for spacecraft operations was demanding: the moon's highly inhomogeneous gravity field distorted the orbit, the regular maneuvers were subject to strict payload-induced pointing requirements, and there were periodic attitude changes to keep the spacecraft thermally safe. This led to a need for high reliability in the operation of the spacecraft while obeying strict budget and schedule guidelines

PANDALP : a new penetrometer for snow investigation

This paper presents a new tool for snow investigation, issued from a portable dynamic penetrometer Panda with variable energy for soil investigation. After a brief presentation of this apparatus, a comparable study between this tool and other tests is carried out. The application of this apparatus in different sights shows that in couple with other tests such us nivological test or temperature test, we could use this portable machine to make snow investigation