An open source,server-side framework for analytical web mapping and its application to health     

Simon Moncrieff  Geoff West  James Cosford  Narelle Mullan  Andrew Jardine 《International Journal of Digital Earth》2014,7(4):294-315

In this paper, we detail the design and the implementation of an open source, server-side web mapping framework for the analysis of health data. The framework forms part of a larger project, the goal of which is to provide an analytical web geographical information system (GIS) that enables health experts to analyse spatial aspects of health data. The aim of the framework is to provide a method for the dynamic and flexible spatial visualisation of health data to facilitate data exploration and analysis. Consequently, a dynamic thematic web mapping technique, an extension to the Open Geospatial Consortium (OGC) web map service standard, was developed. The technique combines a data query, processing technique and styling methodology on the fly to generate a thematic map. The resulting thematic map represents a virtual map layer that enables a user to rapidly visually summarise properties of a data-set. A test web interface was developed to assess the efficacy of the web mapping technique. As the dynamic web mapping method builds on existing OGC web mapping standards, it can be readily integrated with the existing lightweight slippy map web clients and virtual globes.  相似文献   

Marsh-creek connectivity: Fish use of a tidal salt marsh in Southern California     

Janelle M. West  Joy B. Zedler 《Estuaries and Coasts》2000,23(5):699-710

Salt marsh habitats influenced by southern California's mixed, semi-diurnal tides are, on average, accessible to fishes less than 16% of the time. However, five species (four natives, one oxotic) and a variety of juvenile and adult size classes were collected on the marsh surface during a year-long sampling from June 1997 through June 1998 at Sweetwater Marsh National Wildlife Refuge on San Diego Bay.Fundulus parvipinis andGillichthys mirabilis were the most abundant fish species using the marsh. Analyses of their guts revealed that the marsh surface provides a rich foraging area for fishes on high spring tides.F. parvipinnis with marsh access consumed six times as much food as fishes restricted to creek habitats (on a g-food g-fish^?1 basis) and also fed on additional prey types. Because the salt marsh is an important foraging area for fishes, we recommend that restoration projects (especially those intended to mitigate lost fish habitat) include vegetated areas with interconnecting tidal creeks.  相似文献   

Recovery of the long lost minor planet (1179) Mally (Astronomisches Rechen-Institut — Mitteilungen Serie B)     

L. D. Schmadel  R. M. West 《Astronomische Nachrichten》1988,309(3):223-225

The orbit of minor planet (1179) Mally which was supposed to be almost hopelessly lost since its discovery in 1931 is rediscussed. Based on a remeasurement of the original Heidelberg plates, two alternative search ephemerides for the perihelion opposition 1986 have been computed. The object was found on the line of variation very near to the predicted position. The recovery was confirmed by the discovery of additional images on UK Schmidt and ESO Schmidt plates as well as on Palomar Sky Survey exposures. There are no further identities of this faint planet among more than 100,000 reported observations of minor planets in this century. Improved elements based on seven apparitions 1931–1986 are given.  相似文献   

Enhanced nondestructive characterization of ordinary chondrites using complex magnetic susceptibility measurements     

P. Oliver  M. Ralchenko  C. Samson  R. E. Ernst  P. J. A. McCausland  G. F. West 《Meteoritics & planetary science》2018,53(3):433-447

Ordinary chondrites have previously been nondestructively characterized using bulk magnetic susceptibility, broadly reflecting their Fe-Ni alloy content. We seek to expand the information that can be recovered from magnetic susceptibility by using the University of Toronto Electromagnetic Induction Spectrometer (UTEMIS) to measure the complex magnetic susceptibility tensor of 20 ordinary chondrites samples in addition to 16 Gao–Guenie (H5) chondrites at 35 frequencies from 90 Hz to 64 kHz, at variable low applied field strengths <10 A m⁻¹. Following removal of the field-dependent component of susceptibility, frequency dependence, in- and out-of-phase components, and bulk magnetic susceptibility were interpreted. Most meteorites showed no frequency-dependent in-phase responses, but had a frequency-dependent out-of-phase response attributed to eddy currents induced in conductive minerals. Greater in- and out-of-phase frequency dependence correlated with lower fayalite content in olivine and was, in turn, inversely proportional to Fe-Ni alloy content. The uncertainty in the UTEMIS measurements ranges from approximately 0.05% for low-frequency in-phase measurements to a maximum of 3% for low-frequency out-of-phase measurements. This uncertainty level was far lower than the intra-meteorite variability for the Gao–Guenie suite suggesting inhomogeneity at scales of approximately 10 g.  相似文献