Fractal Scaling Properties in Rainfall Time Series: A Case of Thiruvallur District, Tamil Nadu, India

In the present study, the features of rainfall time series (1971–2016) in 9 meteorological regions of Thiruvallur, Tamil Nadu, India that comprises Thiruvallur, Korattur_Dam, Ponneri, Poondi, Red Hills, Sholingur, Thamaraipakkam, Thiruvottiyur and Vallur Anicut were studied. The evaluation of rainfall time series is one of the approaches for efficient hydrological structure design. Characterising and identifying patterns is one of the main objectives of time series analysis. Rainfall is a complex phenomenon, and the temporal variation of this natural phenomenon has been difficult to characterise and quantify due to its randomness. Such dynamical behaviours are present in multiple domains and it is therefore essential to have tools to model them. To solve this problem, fractal analysis based on Detrended Fluctuation Analysis (DFA) and Rescaled Range (R/S) analysis were employed. The fractal analysis produces estimates of the magnitude of detrended fluctuations at different scales (window sizes) of a time series and assesses the scaling relationship between estimates and time scales. The DFA and (R/S) gives an estimate known as Hurst exponent (H) that assumes self-similarity in the time series. The results of H exponent reveals typical behaviours shown by all the rainfall time series, Thiruvallur and Sholingur rainfall region have H exponent values within 0.5 < H < 1 which is an indication of persistent behaviour or long memory. In this case, a future data point is likely to be followed by a data point preceding it; Ponneri and Poondi have conflicting results based on the two methods, however, their H values are approximately 0.5 showing random walk behaviour in which there is no correlation between any part and a future. Thamaraipakkam, Thiruvottiyur, Vallur Anicut, Korattur Dam and Red Hills have H values less than 0.5 indicating a property called anti-persistent in which an increase will tend to be followed by a decrease or vice versa. Taking into consideration of such features in modelling, rainfall time series could be an exhaustive rainfall model. Finding appropriate models to estimate and predict future rainfalls is the core idea of this study for future research.

PHYSICOCHEMICAL AND BIOLOGICAL PARAMETERS OF WATER AT INDUSTRIAL SITES OF METROPOLITAN CITY OF CHENNAI, TAMIL NADU, INDIA

Water is essential to sustain life, and an adequate, safe and accessible supply must be available to all as improving access to safe drinking water can result in tangible benefits to health. In the present study, eighteen water samples from six different study area, viz., Red Hills, T. Nagar, Saidapet, Ashok Nagar, Alandur and Guindy of metropolitan Chennai were tested for their physicochemical and biological parameters, of which Red Hills served as control area. Results with regard to the physical parameters, showed no variation in the colour of water samples which was clear except for control as it appeared light brown. The odour of samples collected from all six study areas was observed to be constant and agreeable. The water temperature, turbidity, electrical conductivity and total dissolved solids for all six study areas ranged from 28.7 to 29.7°C, 3.7 to 11.7NTU, 723.3 to 1099.7μS/cm, and 396.7 to 805.0mg/L. The values of chemical parameters represented by pH, total hardness, total alkalinity, sulphates and flourides ranged from 7.7 to 8.0, 128.0 to 503.3mg/L, 13.3 to 50.0mg/L, 106.6 to 224.0mg/L, and 0.6 and 1.5mg/L. All the samples were found to be free from coliforms except for the control in the case of biological parameters. Overall results indicate that the physical and chemical parameters were found to be within the permissible limits set by standards and biological contamination was absent in the samples except in control which is a natural reservoir.

Vestiges of the Braden Corridor

The widespread exchange of masterful artworks in the Mississippian period has long been a topic of interest among North American archaeologists. The Braden Style, an artistic tradition whose origin has been placed at Cahokia, is recognizable on objects unearthed from locales that are remarkably distant from the American Bottom. In the Tallahassee Red Hills of Florida, the Lake Jackson site hosted burials in Mound 3 that contained a variety of these examples. While the contents of Mound 3’s burials have been investigated to explore ties to other major ceremonial centers in the Greater Southeast, the nature of those ties and their timing have not been fully investigated, especially in consideration of Cahokia. This chapter offers an assemblage based exploration of exchange between these two different and distant sites.

Estimation of Evaporation Loss in Red hills Lake at Thiruvallur District, Tamil Nadu

Redhills lake, Chennai City’s primary reservoir serves as the primary storage nearly about 40 years old. It receives water from Poondi and Cholavaram reservoir and is the last stop before water transmitted to Kalpak Water Works of Metro water. Generally water storage reservoirs are prone to losses through seepage and evaporation. Seepage generally occurs when the water escapes through the bottom of the reservoir and horizontal filtration through weirs and dykes. Owing to the heat energy of sun, water loss take place by evaporation from the surfaces of lakes, ponds, canals, rivers, reservoirs, etc. Water loss by evaporation is a very serious problem in semiarid and arid regions. Red Hills Lake is of no exception. In this thesis, the evaporation losses in Red hills lake is estimated by Bulk Aerodynamic method and Combined Penman Monteith Model using real time meteorological data for the past 10 years (2004 -2013) and compared between them. The relationship between water losses due to evaporation, water level in the lake, lake inflow and lake water storage were carried out. The evaporation values determined by Bulk Aerodynamic Method Which is the function of vapour pressure difference between the water surface and atmosphere, as well as horizontal wind speed varies between 0.20 mm and 39.98 mm with an average of 7.56mm. The evaporation values determined by Combined Penman Model which depends on solar radiation varies between 1.82 mm and 30.54 mm with an average of 9.56 mm..On comparison, Combined Penman Monteith Method showed the better evaporation values and it forms the favouarble method as it depends on minimum factors of solar radiation and sunshine hours for finding evaporation loss in the study area.

Steel Feeling

William Attaway understood the ways workers were being absorbed into a military-industrial complex by way of two world wars and the Wagner Act. With the controversies over a worker’s right to strike in the backdrop, Attaway troubles the American masculine ideals of war and work through “steel feeling.” Attaway’s great skill is in using steel feeling to allow the reader to sense masculine pressure everywhere as the Moss brothers move from the red hills of Kentucky to work in the Allegheny mills. Steel feeling emerges when the inevitable accidents of work in a pressure furnace happen alongside the freak actions of men under all sorts of other pressures: the pressures to be black, to be American, to be free, to be male.