Modelling evaporation using an artificial neural network algorithm

This paper investigates the prediction of Class A pan evaporation using the artificial neural network (ANN) technique. The ANN back propagation algorithm has been evaluated for its applicability for predicting evaporation from minimum climatic data. Four combinations of input data were considered and the resulting values of evaporation were analysed and compared with those of existing models. The results from this study suggest that the neural computing technique could be employed successfully in modelling the evaporation process from the available climatic data set. However, an analysis of the residuals from the ANN models developed revealed that the models showed significant error in predictions during the validation, implying loss of generalization properties of ANN models unless trained carefully. The study indicated that evaporation values could be reasonably estimated using temperature data only through the ANN technique. This would be of much use in instances where data availability is limited. Copyright © 2002 John Wiley & Sons, Ltd.     

Georeference correction on landsat imagery

This paper discusses the geometric anomalies present in bulk images which are being generated on NRSA Data Processing System (DPS). A georeference correction algorithm has been presented to correct geometric scale anomalies in a systematic manner. An approach to generalize and integrate georeference correction algorithm with existing bulk correction program has been realised without crippling the speed of DPS film product generation Software. Limitations and accuracy of the algorithm are discussed.     

On the values of stratospheric circulation index over Natal,Brasil

Summary The SCI values of zonal and meridional winds over Natal, Brasil are calculated. The results are compared with another southern Hemispheric Station Ascension Island and circulation patterns in the Stratosphere are discussed. Also a comparison is made of the zonal winds over Natal with those of an Equatorial Station (Thumba, India) and a station in Subtropics (Sonmiani, Arabian Sea islands).On leave from Dept. of Meteorology and Oceanography, Andhra University, Waltair (India).     

Cultural and economic residential sorting of Auckland’s population, 1991–2013: an entropy approach

Journal of Geographical Systems - Auckland, the largest city of New Zealand, is one of the most diverse cities in the world, with more than 40% of its population born abroad, more than 200...     

Rainfall fluctuations—Break-associated synoptic systems

Summary Monsoon conditions of two types, i.e., active monsoon and break monsoon over a tropical country (India), are studied in detail. Methods of analysis such as cross-sections, time sections, contour analysis of 700 mb (lower troposphere), 500 mb (middle troposphere) and 200 mb (upper troposphere), and streamline analysis are used in the present study. Consistent results are obtained in distinguishing the break monsoon condition to that of an active or normal monsoon condition.     

Assessment of genotoxic and humoral immune system alterations in silica exposed workers from pottery industries in South India

Chemicals, especially silica, have been suspected to cause genetic alterations in pottery industry workers. The present study aims to analyze the frequency of chromosomal aberrations (CA), micronucleus (MN) and DNA damage (comet assay) in the peripheral blood lymphocytes and the immunological alterations workers chronically exposed to silica and in control subjects. In our study, 50 silica exposed workers and 35 control subjects were recruited and silica level was measured by respirable dust and respirable quartz concentrations of badge dosimeter. The serum immunoglobulins (IgM, IgG, and IgA) of all the subjects were measured by using ELISA method. The individuals exposed to silica have a significant increase in the frequency of CA, MN and the total DNA damage (p < 0.05). Immunoglobulin elevation on silica exposed workers was statistically significant (p < 0.05) on comparison with their respective controls. Investigation of the smoking and alcohol habitats coupled with silica exposure in exposed and control subjects represents alcohol consumption and smoking as additional risk factors and must be avoided. Multiple linear regression analysis obtained for CA, MN and comet assay confirm these tests as biomarkers for silica exposed pottery workers. Some confounding factors also showed significant influence on exposed subjects. These results indicate the mutagenic risk in the working environment has a high probability of association with the silica dust exposure in pottery industries. Nevertheless, the present study will create awareness and public concern not only among the silica exposed workers but also to the welfare of their progeny.     

Moisture relationships for the Southern Hemisphere

Values for mean precipitable water are computed for four seasons of the year and for different regions of the Southern Hemisphere. Relationships between surface dew-point temperature and precipitable water were studied for these regions. A harmonic analysis of our data on precipitable water is attempted. Out results are presented and discussed.     

A preliminary study of precipitable water over Brazil

A preliminary study of precipitable water over Brazil is attempted. Mean values for January are presented in this paper. A regression equation connecting the surface dew-point temperature and the precipitable water was computed along the lines of studies made by Reitan (1963), and the results are presented.     

Migratory Patterns and Settlement Experiences of African Australians of Refugee Background in Murray Bridge,South Australia

In the past decade Australian immigration policy has emphasised settlement of refugees/humanitarian entrants in rural and regional locations, in preference to metropolitan areas. The settlement outcomes of a case study of African humanitarian entrants of South Sudanese background in Murray Bridge, a regional centre in South Australia, are examined. These participants were self-settled secondary movers from metropolitan Adelaide. The factors which attracted them were centred on employment. Settlement outcomes for Murray Bridge respondents were better than their urban counterparts, in terms of both housing and employment outcomes. However, some later left Murray Bridge because of a lack of opportunities for tertiary education. The results highlight issues of sustainability of settlement and retention, in regional centres in Australia, and of the fluidity of attraction and retention factors and therefore settlement in regional centres.