Development of vendor evaluation criteria and post-implementation considerations for MSFC center-wide executive information system

In June 1991, the MITRE Corporation submitted a series of recommendations as part of a Marshall Space Flight Center (MSFC) Management Information System Requirements Study, initiated by the Information Systems Office (ISO). A major recommendation of the study was to develop an Executive Information System (EIS) for MSFC executives. ISO was directed, by center management, to proceed with the development of a Center-Wide Executive Information System. Existing EIS prototypes, developed by the Space Shuttle Projects Office and the Payload Projects Office, were reviewed. These existing MSFC prototypes were considered not to encompass the required functionality needed on a center-wide basis. A follow-up study by MITRE provided top-level system requirements. These were later incorporated into a final requirements specification document by Boeing Computer Support Services

Commentary on session II: The politics of migration and trade

Summary and discussion of the two papers in this session: "U.S.-Mexican migration cooperation: obstacles and opportunities" by Marc R. Rosenblum; "Political implications of U.S. public attitudes toward immigration on the immigration policymaking process" by Valerie F. HuntEmigration and immigration ; International trade ; Public policy

Lyapunov Modes and Time-Correlation Functions for Two-Dimensional Systems

The relation between the Lyapunov modes (delocalized Lyapunov vectors) and the momentum autocorrelation function is discussed in two-dimensional hard-disk systems. We show numerical evidence that the smallest time-oscillating period of the Lyapunov modes is twice as long as the time-oscillating period of momentum autocorrelation function for both square and rectangular two-dimensional systems with hard-wall boundary conditions.Comment: 9 pages, 4 figure

Properties of mass-loading shocks: 1. Hydrodynamic considerations

The one-dimensional hydrodynamics of flows subjected to mass loading are considered anew, with particular emphasis placed on determining the properties of mass-loading shocks. This work has been motivated by recent observations of the outbound Halley bow shock (Neubauer et al., 1990), which cannot be understood in terms of simple hydrodynamical or magnetohydrodynamical descriptions. By including mass injection at the shock, we have investigated the properties of the Rankine-Hugoniot conditions on the basis of a geometric formulation of the entropy condition. Such a condition, which is more powerful than the usual thermodynamical formulation, serves to determine those solutions to the Rankine-Hugoniot conditions which correspond to a physically realizable downstream state. On this basis a concise theoretical description of hydrodynamic mass-loading shocks is obtained. We show that mass-loading shocks have more in common with combustion shocks than with ordinary nonreacting gas dynamical shocks. It is shown that for decelerated solutions to the Rankine-Hugoniot conditions to exist, the upstream flow speed u0 must satisfy u0 > ucrit > cs, where cs is the sound speed. Besides the usual supersonic-subsonic transition, mass-loading fronts can also admit a decelerating supersonic-supersonic transition, the structure of which consists of a sharp decrease in the flow velocity preceding a recovery and an increase in the final downstream flow speed. We suggest the possibility that such structures may describe the inbound Halley bow shock (Coates et al., 1987a). Both parallel and oblique shocks are considered, the primary difference being that oblique shocks are subjected to a shearing stress due to mass loading. It is conjectured that such a shearing may destabilize the shock

Common Core State Standards in Arkansas

In July 2010, the Arkansas Board of Education adopted the Common Core State Standards and the PARCC Assessment program. The Arkansas Department of Education (ADE) then created a strategic plan and a timeline for the implementation of the standards. The new standards were implemented in Arkansas K-2 classrooms this past school year, 2011-12. During this current school year, 2012-13, the standards are being implemented in grades 3-8

Changes in fish populations in the Lower Canyons of the Rio Grande

The Lower Canyons of the Rio Grande suffer from environmental degradation that has negatively impacted native fish populations and their distributions. Macrhybopsis aestivalis (speckled chub), Notropis jemezanus (Rio Grande shiner), Rhinichthys cataractae (longnose dace) and Cycleptus elongatus (blue sucker) populations appear to have suffered recent declines. Although diminished water quantity is likely an important factor in these declines, related changes in channel morphology precipitated by massive stands of Arundo donax (giant reed) and Tamarix sp. (salt cedar) may also be responsible. These invasive exotics have essentially channelized the river, disrupted normal sediment distribution and reduced shallow, low-velocity habitats. Much of the Lower Canyons of the Rio Grande are devoid of sandy sediment and most riffles are now composed of gravel and cobble.Integrative Biolog