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721.
Oliver T. Coomes Tim Moore Jaclyn Paterson Sébastien Breau Nancy A. Ross Nigel Roulet 《The Professional geographer》2013,65(3):433-450
A common problem faced by geography departments, particularly during times of fiscal compression and mounting pressure for accountability, is how to compare themselves and their faculty with others. The recent revolution in bibliometrics provides a growing volume of data that can be used in benchmarking exercises. In this article, we assess the production and citation of journal articles and books by tenure-track and tenured faculty in selected U.S. and Canadian geography departments (n = 17) according to a set of readily derived and transparent performance indicators derived from publicly available data. Scopus was used to assess article production and citation; Google Scholar was used for book citation. Results point to significant heterogeneity in department characteristics, productivity, and citation of published work. The number of publications, citations, and h-Index scores among scholars in the sample (n = 369) is related strongly to academic age and subfield of enquiry (i.e., physical or human geography) but not—despite apparently marked differences in output and citations—to gender. 相似文献
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Analysis of data collected between 1950 and 1995 in the state of Indiana indicates that the state experiences an average of nearly 19 tornadoes each year, which occur on approximately 8 or 9 days during an average year. Analysis of storm dimensions indicates that the annual probability of a point location in Indiana being impacted by a tornado is 1.4 × 10-4 per year. The largest number of the more intense tornadoes (F2 and higher) typically occur from March to June, during the afternoon and evening, although tornadoes have been observed in each month of the year and each hour of the day. Inter-annual variability of tornadic events in Indiana is large and may reflect both physical causes (e.g., the variability of cyclone passages or jet stream location) and recording bias (e.g., increased public awareness during the 1950s). Using the data set from Indiana, statistical analyses of the temporal and spatial variability of tornadoes are undertaken. Analyses of tornado reports by county indicate that, in addition to area and population, surface roughness is a significant determinant of event frequency. Analyses presented herein also indicate that in contrast to previous studies, (1) no statistically significant hebdomadal cycle of tornado reporting is evident in the data and (2) the diurnal cycle of tornado records is evident for all F-scale classes and is not confined largely to the weak tornado categories. Analyses of the physical dimensions and F-scale ratings of tornadoes in Indiana indicate that there has been a decline in reported tornado intensity, width, and length between 1950 and 1995. These changes are in accord with evidence of a decreasing number of reports of strong and violent tornadoes across the United States over this period and appears to be principally a result of reporting biases at the beginning of the record. [Key words: tornado climatology, temporal and spatial variability, reporting bias.] 相似文献
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R. Bacon Y. Copin G. Monnet Bryan W. Miller J.R. Allington-Smith M. Bureau C. Marcella Carollo Roger L. Davies Eric Emsellem Harald Kuntschner Reynier F. Peletier E.K. Verolme P. Tim de Zeeuw 《Monthly notices of the Royal Astronomical Society》2001,326(1):23-35
A new integral-field spectrograph, SAURON, is described. It is based on the TIGER principle, and uses a lenslet array. SAURON has a large field of view and high throughput, and allows simultaneous sky subtraction. Its design is optimized for studies of the stellar kinematics, gas kinematics, and line-strength distributions of nearby early-type galaxies. The instrument design and specifications are described, as well as the extensive analysis software which was developed to obtain fully calibrated spectra, and the associated kinematic and line-strength measurements. A companion paper will report on the first results obtained with SAURON on the William Herschel Telescope. 相似文献
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The SAURON project – III. Integral-field absorption-line kinematics of 48 elliptical and lenticular galaxies 总被引:1,自引:0,他引:1
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In this study, a Bayesian Network (BN) is used to model the suspended sediment concentrations (SSC) in the catchments of the glaciers Noir and Blanc in the Ecrins National Park, France, and at the distal end of the proglacial zone into which both torrents drain. Relationships between air temperature, glacier discharge and SSC are represented as random variables; thereby taking the natural next step from proposed modified rating curve methods which increasingly approximate random variable approaches. Hydrological relationships are propagated through the network via conditional probability distributions computed from 980 field records obtained at three monitoring sites during July 2005. Rainfall affected data are removed from the modelling process. A two‐sample Kolmogorov–Smirnov goodness‐of‐fit (two‐sample KS) test (n = 5) shows good agreement between the probability distributions of SSC predicted by the BN, and those recorded in the field at the outflow of the proglacial zone over an air temperature range of 5–25 °C. The BN performs poorly for air temperatures between 25 and 30 °C and this is attributed to limited field records covering this temperature range. Discussion of the significant limitations surrounding the widespread application of BNs in hydrological modelling are offered with a focus on data volume and temporal limitations. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
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