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A neurocomputing approach to predict monsoon rainfall in monthly scale using SST anomaly as a predictor

Acharya N.A., Chattopadhyay S., Kulkarni M.A.

Acta Geophysica

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2012

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Vol. 60, no. 1

260-279

EN

A relationship between summer monsoon rainfall and sea surface temperature anomalies was investigated with the aim of predicting the monthly scale rainfall during the summer monsoon period over a section (80°–90°E, 14°–24°N) of eastern India that depends heavily upon the rainfall during the summer monsoon months for its agricultural practices. The association between area-averaged rainfall of June over the study zone and global sea surface temperature (SST) anomalies for the period 1982–2008 was examined and the variability of rainfall in monthly scale was calculated. With a view to significant variability in the rainfall in the monthly scale, it was decided to implement the artificial neural network (ANN) for forecasting the monthly scale rainfall using the SST anomalies as a predictor. Finally, the potential of ANN in this prediction has been assessed.

2

Feed forward Artificial Neural Network model to predict the average summer-monsoon rainfall in India

Chattopadhyay S.

Acta Geophysica

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2007

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Vol. 55, no. 3

369-382

EN

In the present research, possibility of predicting average summer-monsoon rainfall over India has been analyzed through Artificial Neural Network model. In formulating the ANN – based predictive model, three-layer network has been constructed with sigmoid non-linearity. The monthly summer monsoon rainfall totals, tropical rainfall indices and sea surface temperature anomalies have been considered as predictors while generating the input matrix for the ANN. The data pertaining to the years 1950-1995 have been explored to develop the predictive model. Fi-nally, the prediction performance of neural net has been compared with persistence forecast and Multiple Linear Regression forecast and the supremacy of the ANN has been established over the other processes.

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Preliminary results on direct photon-photon HBT measurements in square root sNN = 62.4 GeV and 200 GeV Au+Au collisions at RHIC

Das D., Lin G., Chattopadhyay S., Chikanian A., Finch E., Nayak T., Panitkin S., Sandweiss J., Suaide A., Zhang H.

Nukleonika

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2006

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Vol. 51,suppl.3

55--58

EN

We present the preliminary results on direct photon interferometry measurements in Au+Au collisions at square root sNN = 62.4 GeV and 200 GeV using the STAR (solenoidal tracker at RHIC) detector. Photons are reconstructed via e+/e- conversions in STAR Time Projection Chamber (TPC) and energy deposited by photons in STAR Barrel Electromagnetic Calorimeter (BEMC). The two-photon correlations are measured using (1) both photons measured with BEMC; (2) one photon from conversions and the other measured with BEMC. Both the methodologies and the possible constraints in the correlation function measurements are discussed.