Average Analysis (average + analysis)

Distribution by Scientific Domains


Selected Abstracts


Temporal and spatial rainfall analysis across a humid tropical catchment

HYDROLOGICAL PROCESSES, Issue 3 2001
P. Campling
Abstract Temporal and spatial rainfall patterns were analysed to describe the distribution of daily rainfall across a medium-sized (379km2) tropical catchment. Investigations were carried out to assess whether a climatological variogram model was appropriate for mapping rainfall taking into consideration the changing rainfall characteristics through the wet season. Exploratory, frequency and moving average analyses of 30 years' daily precipitation data were used to describe the reliability and structure of the rainfall regime. Four phases in the wet season were distinguished, with the peak period (mid-August to mid-September) representing the wettest period. A low-cost rain gauge network of 36 plastic gauges with overflow reservoirs was installed and monitored to obtain spatially distributed rainfall data. Geostatistical techniques were used to develop global and wet season phase climatological variograms. The unscaled climatological variograms were cross-validated and compared using a range of rainfall events. Ordinary Kriging was used as the interpolation method. The global climatological variogram performed better, and was used to optimize the number and location of rain gauges in the network. The research showed that although distinct wet season phases could be established based on the temporal analysis of daily rainfall characteristics, the interpolation of daily rainfall across a medium-sized catchment based on spatial analysis was better served by using the global rather than the wet season phase climatological variogram model. Copyright © 2001 John Wiley & Sons, Ltd. [source]


Smoothed analysis of some condition numbers

NUMERICAL LINEAR ALGEBRA WITH APPLICATIONS, Issue 1 2006
F. Cucker
Abstract In this note we do a smoothed analysis, in the sense of (http://www-math.mit.edu/,spielman/SmoothedAnalysis/), of the condition number for the Moore,Penrose inverse. Usual average analysis follows in a trivial manner as follow similar analyses for the condition number of the polar factorization. Copyright © 2005 John Wiley & Sons, Ltd. [source]


Application of random amplified polymorphic DNA and inter-simple sequence repeat markers in the genus Crataegus

ANNALS OF APPLIED BIOLOGY, Issue 2 2009
H. Dai
Abstract Hawthorn (Crataegus spp.) has a long history as an ornamental and a source of medicine. We report the use of random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) markers to determine genetic relationships in the genus Crataegus. Twenty-eight accessions, including eight species (Crataegus pinnatifida, Crataegus bretschneideri, Crataegus maximowiczii, Crataegus kansuensis, Crataegus altaica, Crataegus songarica, Crataegus dahurica and Crataegus sanguinea) and two botanical varieties (C. pinnatifida var. major and C. maximowiczii var. ninganensis) were analysed. Twelve RAPD primers reproducibly and strongly amplified 128 fragments of which 116 were polymorphic; similarly, 13 ISSR primers generated 127 products of which 119 were polymorphic. Dendrograms based on unweighted pair group method with arithmetic average analysis were constructed from both the RAPD and the ISSR data. Similarity coefficient based on RAPD and ISSR markers ranged from 0.22 to 0.98 and 0.23 to 0.98, respectively. The range in similarity coefficient indicated that the genus has a high level of genetic diversity. The Mantel test on the similarity matrices produced by RAPD and ISSR markers gave r = 0.86, showing high correlation between RAPD and ISSR markers in their ability to detect genetic relationships between Crataegus accessions. RAPD and ISSR appear to be reliable methods for the analysis of genetic relationships among hawthorns. [source]


Genetic diversity, presence of the syrB gene, host preference and virulence of Pseudomonas syringae pv. syringae strains from woody and herbaceous host plants

PLANT PATHOLOGY, Issue 3 2003
M. Scortichini
A total of 101 Pseudomonas syringae pv. syringae strains, obtained from international culture collections or isolated from diseased tissues of herbaceous and woody plant species, were assessed by repetitive PCR using the BOX primer, and for the presence of the syrB gene. Representative strains were also tested for pathogenicity to lilac, pear, peach, corn and bean, as well as for virulence to lemon and zucchini fruits. The unweighted pair-group method using arithmethic averages analysis (UPGMA) of genomic fingerprints revealed 17 different patterns which grouped into three major clusters, A, B and C. Most of the strains (52·4%) were included in patterns 1,4 of group A. These patterns comprised strains obtained from either herbaceous or woody species, and showed four fragments of similar mobility. Genetic variability was ascertained for strains isolated from apple, pear, apricot, Citrus spp. and cereals. No clear relationship was observed between host plant and bacterial genomic fingerprint. Variability was also observed in pathogenicity and virulence tests. The inoculation of pear leaves discriminated strains isolated from pear as well as the very aggressive strains, whereas inoculation of lilac, peach and corn did not discriminate the host plant from which the strains were originally isolated. Lemon fruit inoculation proved very effective for P. syringae pv. syringae virulence assessment. The syrB gene was present in almost all strains. [source]