Program management model study

Two models, a system performance model and a program assessment model, have been developed to assist NASA management in the evaluation of development alternatives for the Earth Observations Program. Two computer models were developed and demonstrated on the Goddard Space Flight Center Computer Facility. Procedures have been outlined to guide the user of the models through specific evaluation processes, and the preparation of inputs describing earth observation needs and earth observation technology. These models are intended to assist NASA in increasing the effectiveness of the overall Earth Observation Program by providing a broader view of system and program development alternatives

Characterizing the universal rigidity of generic frameworks

A framework is a graph and a map from its vertices to E^d (for some d). A framework is universally rigid if any framework in any dimension with the same graph and edge lengths is a Euclidean image of it. We show that a generic universally rigid framework has a positive semi-definite stress matrix of maximal rank. Connelly showed that the existence of such a positive semi-definite stress matrix is sufficient for universal rigidity, so this provides a characterization of universal rigidity for generic frameworks. We also extend our argument to give a new result on the genericity of strict complementarity in semidefinite programming.Comment: 18 pages, v2: updates throughout; v3: published versio

Reanalysis of Farmer Willingness to Tolerate Deer Damage in Western New York

Crop depredation by white-tailed deer (Odocoileus uirginianus) has been examined and discussed by wildlife managers since at least the early 1930\u27s (Leopold 1933:283). As with most aspects of game management in those early years, managers\u27 efforts focused on the biological parameters of depredation and control. In the 1960\u27s a few researchers began examining the social implications of deer management and found farmers to be surprisingly tolerant of most deer damage (McDowell and Benson 1960, McNeil 1962:81, Flyger and Thoerig 1962:48). Because of changing agricultural, habitat, and deer population conditions, studies of farmer tolerance of deer damage were initiated in New York (Brown et al. 1977, 1978, 1979, 1980). This research helped to systematically quantify and apply the concept of farmer tolerance of deer damage as a determinant of deer range carrying capacity on agricultural lands in New York State

Interventions for improving clinical outcomes and health-related quality-of-life for people living with skeletal dysplasias: an evidence gap map

Purpose: Skeletal dysplasias are rare genetic disorders that are characterized by abnormal development of bone and cartilage. There are multiple medical and non-medical treatments for specific symptoms of skeletal dysplasias e.g. pain, as well as corrective surgical procedures to improve physical functioning. The aim of this paper was to develop an evidence-gap map of treatment options for skeletal dysplasias, and their impact on patient outcomes. Methods: We conducted an evidence-gap map to identify the available evidence on the impact of treatment options on people with skeletal dysplasias on clinical outcomes (such as increase in height), and dimensions of health-related quality of life. A structured search strategy was applied to five databases. Two reviewers independently assessed articles for inclusion in two stages: titles and abstracts (stage 1), and full text of studies retained at stage 2. Results: 58 studies fulfilled our inclusion criteria. The included studies covered 12 types of skeletal dysplasia that are non-lethal with severe limb deformities that could result in significant pain and numerous orthopaedic interventions. Most studies reported on the effect of surgical interventions (n = 40, 69%), followed by the effect of treatments on dimensions of health quality-of-life (n = 4, 6.8%) and psychosocial functioning (n = 8, 13.8%). Conclusion: Most studies reported on clinical outcomes from surgery for people living with Achondroplasia. Consequently, there are gaps in the literature on the full range of treatment options (including no active treatment), outcomes and the lived experience of people living with other skeletal dysplasias. More research is warranted to examine the impact of treatments on health-related quality-of-life of people living with skeletal dysplasias, including their relatives to enable them to make preference- and valued based decisions about treatment

X-Ray Groups of Galaxies in the Aegis Deep and Wide Fields

We present the results of a search for extended X-ray sources and their corresponding galaxy groups from 800-ks Chandra coverage of the All-wavelength Extended Groth Strip International Survey (AEGIS). This yields one of the largest X-ray selected galaxy group catalogs from a blind survey to date. The red-sequence technique and spectroscopic redshifts allow us to identify 100$$ of reliable sources, leading to a catalog of 52 galaxy groups. The groups span the redshift range $z\sim0.066-1.544$ and virial mass range $M_{200}\sim1.34\times 10^{13}-1.33\times 10^{14}M_\odot$. For the 49 extended sources which lie within DEEP2 and DEEP3 Galaxy Redshift Survey coverage, we identify spectroscopic counterparts and determine velocity dispersions. We select member galaxies by applying different cuts along the line of sight or in projected spatial coordinates. A constant cut along the line of sight can cause a large scatter in scaling relations in low-mass or high-mass systems depending on the size of cut. A velocity dispersion based virial radius can more overestimate velocity dispersion in comparison to X-ray based virial radius for low mass systems. There is no significant difference between these two radial cuts for more massive systems. Independent of radial cut, overestimation of velocity dispersion can be created in case of existence of significant substructure and also compactness in X-ray emission which mostly occur in low mass systems. We also present a comparison between X-ray galaxy groups and optical galaxy groups detected using the Voronoi-Delaunay method (VDM) for DEEP2 data in this field.Comment: Accepted for publication in AP

Uranium-lead isotope systematics of Mars inferred from the basaltic shergottite QUE 94201

Uranium-lead ratios (commonly represented as {sup 238}U/{sup 204}Pb = {mu}) calculated for the sources of martian basalts preserve a record of petrogenetic processes that operated during early planetary differentiation and formation of martian geochemical reservoirs. To better define the range of {mu} values represented by the source regions of martian basalts, we completed U-Pb elemental and isotopic analyses on whole rock, mineral and leachate fractions from the martian meteorite Queen Alexandra Range 94201 (QUE 94201). The whole rock and silicate mineral fractions have unradiogenic Pb isotopic compositions that define a narrow range ({sup 206}Pb/{sup 204}Pb = 11.16-11.61). In contrast, the Pb isotopic compositions of weak HCl leachates are more variable and radiogenic. The intersection of the QUE 94201 data array with terrestrial Pb in {sup 206}Pb/{sup 204}Pb-{sup 207}Pb/{sup 204}Pb-{sup 208}Pb/{sup 204}Pb compositional space is consistent with varying amounts of terrestrial contamination in these fractions. We calculate that only 1-7% contamination is present in the purified silicate mineral and whole rock fractions, whereas the HCl leachates contain up to 86% terrestrial contamination. Despite the contamination, we are able to use the U-Pb data to determine the initial {sup 206}Pb/{sup 204}Pb of QUE 94201 (11.086 {+-} 0.008) and calculate the {mu} value of the QUE 94201 mantle source to be 1.823 {+-} 0.008. This is the lowest {mu} value calculated for any martian basalt source, and, when compared to the highest values determined for martian basalt sources, indicates that {mu} values in martian source reservoirs vary by at least 100%. The range of source {mu} values further indicates that the {mu} value of bulk silicate Mars is approximately three. The amount of variation in the {mu} values of the mantle sources ({mu} {approx} 2-4) is greater than can be explained by igneous processes involving silicate phases alone. We suggest the possibility that a small amount of sulfide crystallization may generate large extents of U-Pb fractionation during formation of the mantle sources of martian basalts