Weighted-R-Trees

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Wood density and ring width in Quercus rotundifolia trees in southern Portugal

Quercus rotundifolia Lam., known as holm oak or evergreen oak, occurs naturally in the western Mediterranean region, mainly as part of the agroforestry or agrosilvopastoral systems in Portugal (“montado”) and Spain (“dehesa”), and is economically important for acorn production. Less attention has been given to Q. rotundifolia wood, and its density variability is not known, namely related to tree growth. The wood density of 20 Q. rotundifolia trees was measured along the radial direction by X-ray densitometry and the factors responsible for ring width and wood density variation within and between trees were investigated at two sites located within the main species region in southern Portugal. Ring width was significantly different between sites, with an average of 1.81 mm and 1.55 mm. Wood density was very high and averaged between 888 kg/m3 and 914 kg/m3 but not significantly different between sites. Ring width and wood density showed a positive and significant correlation at both sites. Cambial age was the main source of variation for ring width and wood density, while between-tree effects accounted for a considerable proportion of wood density variation. The results are an important contribution for the species valorisation aiming at high-value wood products, also adding knowledge on the species growth of interest for tree selection and sustainable managementinfo:eu-repo/semantics/publishedVersio

Iowa Conservationist, September 1961, Vol. 20, no.9

This newsletter is produced by the Iowa Department of Natural Resources, formally Iowa State Conservation Commission. This newsletter contains news and stories relating to all aspects of hunting, fishing, trapping, conservation and utilizing the outdoor resources of Iowa

Annual report of the selectmen, treasurer, and other town officers for the town of Newbury, New Hampshire for the fiscal year ending December 31, 2015 and the vital statistics for the year 2015.

This is an annual report containing vital statistics for a town/city in the state of New Hampshire

Response of three semi-arid savannas on contrasting soils to the removal of the woody component

A thesis submitted to the Faculty of Science University of the Witwatersrand, Johannesburg for the Degree or Doctor or Philosophy October 1987A t h r e e - y e a r study was un dertaken in the semi-arid (500mm p a . ) n o rth -eastern lowland area of South Afric a. All the woody plants were removed from one -hectare savanna plots on three d i f f e r e n t soil types , and key hydrological and biological changes were monitored relative to adjacent controls. Runoff increased initially, but decreased once the grass cover increased. Deep drainage and lateral subsurface flow increased on the sandiest site. Evaporation from the soil surface increased on the heavier t e x t u r e d soils. The duration of plant - available water in the soil increased on all cleared p l o t s . & The p re - c l e a r in g woody plant abo veground biomass was in the range of of which 0 . 6 6 to 0 . 8 0 t ha was 5.6 to 11.2 t ha -1 leaf biomass. The annual herbaceous production was stron gly rainfal' dep endent, averaging 1 to 1.5 t ha -1 , and increased by 0 . 4 - 0 6 t .ha -1 except on the most f erti le site ( 0 . 6 - 2 0 t ha ) . Total available forage increased with c l e a ring, but so did its variability The observed changes in herbaceous layer palatability could not be a t trib u t e d to clearing. Woody plants and grasses wore shown to have w a te r- u s e niche separation in both rooting depth and time of water use. Simulation over forty years of wetting patterns indicated 75 to 85 % niche overlap, w t h separation on the depth axis more important in sandy sites, and on the time axis in clayey sites. Competition between woody plants and grasses was strongly asymmetrical in favour of woody plants. w

The Sound of William Barnes's Dialect Poems: 3. Poems of Rural Life in the Dorset Dialect, third collection (1862)

"This is the third volume in a series that sets out to provide a phonemic transcript and an audio recording of each individual poem in Barnes’s three collections of Poems of Rural Life in the Dorset Dialect. With 96 poems in an astonishing variety of metrical forms, the volume includes some of those that are most loved and admired: poems of tragedy (“Woak Hill”, “The turnstile”) and comedy (“John Bloom in Lon’on”, “A lot o’ maïdens a-runnèn the vields”); celebrations of love anticipated (“In the spring”) and love fulfilled (“Don’t ceäre”); protests against injustice and snobbery (“The love child”); struggles to accept God’s will (“Grammer a-crippled”); and poems on numerous other subjects, with an emotional range stretching from the deepest of grief to the highest of joy.

The sound of William Barnes's dialect poems: 3. Poems of rural life in the Dorset dialect, third collection (1862)

This series, developed from Tom Burton’s groundbreaking study, William Barnes’s Dialect Poems: A Pronunciation Guide (The Chaucer Studio Press, 2010), sets out to demonstrate for the first time what all of Barnes’s dialect poems would have sounded like in the pronunciation of his own time and place. Every poem is accompanied by a facing-page phonemic transcript and by an audio recording freely available from this website.T. L. Burto

WeR-trees

R-tree has been proven to be one of the most practical and well-behaved data structures for accommodating dynamic massive sets of low dimensionality geometric objects and conducting a very diverse set of queries on such data sets in real-world applications. In this paper, we present weighted R-trees-WeR-trees-a new practical and efficient scheme for dynamic manipulation of multi-dimensional data sets, which applies for the first time the technique of partial rebuildings to the case of the R-tree family. Partial rebuildings refer to the method of progressive reconstruction of whole subtrees across update paths in order to keep them in perfect balance from the performance perspective. An analytical investigation is performed, showing amortized bounds for the update operations while detailed experimental results concerning both synthetic and real data sets confirm the applicability of the proposed method and demonstrate its superiority over R*-trees, the most well-behaved and widely accepted variant of R-trees: node space utilization reaches up to 98.1%, query savings vary between 25% and 50% and even more for skewed data, while the scheme scales up linearly with respect to the number of inserted items. (c) 2007 Elsevier B.V. All rights reserved