GIS based spatial distribution mapping and suitability evaluation of groundwater quality for domestic and agricultural purpose in Kaithal district, Haryana state, India

Groundwater is a major resource for meeting huge domestic and agricultural requirements of Kaithal district in Haryana. Therefore, evaluation of its quality in terms of suitability for domestic and agricultural sectors is necessary for sustainable management of the resource. The present study has analyzed pre- and post-monsoon physico-chemical data of groundwater samples from bore wells spread over the entire district. Spatial distribution maps were generated for hydrogen ion concentration, total dissolved solids, total hardness, electrical conductivity, sodium adsorption ratio, residual sodium carbonate and percent sodium using the geographic information system. Furthermore, the study area was demarcated into different groundwater quality zones for domestic and agricultural use by applying various national and international standards. It was observed from the study that the groundwater was predominantly hard, alkaline and saline in nature. However, it was within safe limits for domestic use. Further, it was also experienced from the analysis that in about two-third parts of the district, groundwater was in desirable-to-permissible quality class for agricultural use but hazardous for soil as well as for crops in the remaining part. Also, a moderation in water quality was observed after the monsoon season, which can be attributed to a possible dilution due to groundwater recharge.     

On the Photometric Error Calibration for the Differential Light Curves of Point-like Active Galactic Nuclei

It is important to quantify the underestimation of rms photometric errors returned by the commonly used APPHOT algorithm in the IRAF software, in the context of differential photometry of point-like AGN, because of the crucial role it plays in evaluating their variability properties. Published values of the underestimation factor, η, using several different telescopes, lie in the range 1.3–1.75. The present study aims to revisit this question by employing an exceptionally large data set of 262 differential light curves (DLCs) derived from 262 pairs of non-varying stars monitored under our ARIES AGN monitoring program for characterizing the intra-night optical variability (INOV) of prominent AGN classes. The bulk of these data were taken with the 1-m Sampurnanad Telescope (ST). We find η?=?1.54±0.05 which is close to our recently reported value of η?=?1.5. Moreover, this consistency holds at least up to a brightness mismatch of 1.5 mag between the paired stars. From this we infer that a magnitude difference of at least up to 1.5 mag between a point-like AGN and comparison star(s) monitored simultaneously is within the same CCD chip acceptable, as it should not lead to spurious claims of INOV.     

Drive-Control System for the TACTIC Gamma-Ray Telescope

A PC-based drive-control system has been developed for the altitude-azimuth mounted TACTIC -ray telescope to control the speed and direction of motion of its 2-axes. Details of various hardware components chosen for the telescope, including hybrid-stepper motor, 16-bit absolute encoder and CAMAC-based programmable stepper motor controller, are discussed in this paper. The telescope-control strategy, based on the position-loop with a proportional type control for the source-seek mode and the on/off type control for the tracking mode, is explained in detail. Some important performance features of the telescope, including its blind-spot size, drive-system backlash and encoder-error compensation, are also presented. The drive system has been extensively field-tested and has been operating satisfactorily during observation campaigns carried out since March 1997 with the TACTIC Imaging Element. A tracking accuracy of ±3 arc-minutes has been achieved. A test report of its performance, with regard to its tracking accuracy on the basis of successful detection of TeV -rays from the active galaxy Markarian 501 in April–May 1997, is also presented.     

Earthquake analysis of intake-outlet towers including tower-water-foundation-soil interaction

The available procedure for earthquake analysis of axisymmetric intake-outlet towers is extended to towers of arbitrary geometry, but with two axes of plan symmetry, and to include the effects of tower-foundation-soil interaction. The total system is represented as four substructures: tower, surrounding water, contained water and the foundation supported on flexible soil. The substructure representation of the system permits use of the most effective idealization for each substructure. An example earthquake response analysis is presented to demonstrate the results obtained from the analysis procedure. Computation times for several cases are included to demonstrate the efficiency of the analysis procedure.     

MODFLOW based groundwater resource evaluation and prediction in Mendha sub-basin,NE Rajasthan

A direct approach to designing MODFLOW finite difference model is tedious and less intuitive, specifically for complex boundary and initial conditions. Therefore, a MODFLOW model can be developed either using a grid or conceptual model approach. The conceptual model is created using Geographic Information System (GIS) objects including points, arcs and polygons so that it can more accurately represent real world condition. It is a simplified representation of the site to be modelled including the model domain, boundary conditions, sources, sinks and material zones. Advantage of conceptual model is that most of the input can be in terms of physical objects, such as wells, lakes, recharge zones etc which can then be converted to a grid based mathematical model with the help of preprocessor software. This paper presents the results of a mathematical groundwater model developed for the northern part of Mendha sub-basin in the semi arid region of northeastern Rajasthan, employing conceptual groundwater modelling approach. For this purpose, Groundwater Modelling Software (GMS) was used which supports the MODFLOW-2000 code. For the purpose of modelling the Source/ Sink Coverage, Recharge Coverage, Extraction Coverage, Return Flow Coverage and Soil Coverage were considered. The model was calibrated against the historical and observed water level data for periods 1998 to 2003 and 2003 to 2005 respectively.     

Spatial Modeling for Base-Metal Mineral Exploration Through Integration of Geological Data Sets

This study involves the integration of information interpreted from data sets such as LandsatTM, Airborne magnetic, geochemical, geological, and ground-based data of Rajpura—Dariba,Rajasthan, India through GIS with the help of (1) Bayesian statistics based on the weights ofevidence method and (2) a fuzzy logic algorithm to derive spatial models to target potentialbase-metal mineralized areas for future exploration. Of the 24 layers considered, five layers(graphite mica schist (GMS), calc-silicate marble (CALC), NE-SW lineament 0–2000 mcorridor (L4-NESW), Cu 200–250 ppm, and Pb 200–250 ppm) have been identified from theBayesian approach on the basis of contrast. Thus, unique conditions were formed based onthe presence and absence of these five map patterns, which are converted to estimate posteriorprobabilities. The final map, based on the same data used to determine the relationships, showsfour classes of potential zones of sulfide mineralization on the basis of posterior probability.In the fuzzy set approach, membership functions of the layers such as CALC, GMS, NE-SWlineament corridor maps, Pb, and Cu geochemical maps have been integrated to obtain thefinal potential map showing four classes of favorability index.     

Remote sensing applications in the study of landuse and soils of aeolian cover op the western part of Haryana State

Multispectral and multitemporal landsat-FCC of 1:250,000 and transparancies on 1:1000,000 scales of bands 4, 5, 6 and 7 were interepreted to identify and delineate the areas under varying intensities of dunal activity in the western part of Haryana State comprising an area of 12610 sq. km. CCTs of some representative areas were also interpreted on the Multispectral Interactive Data Analysis System. Field checks were made to correlate the laboratory interpretation and the ground truth. The study areas were differentiated into the following units: (1) Sandy desert zone: No cultivation on dune tops except some shrubs, (2) Aeolian cover with sandy hummocks: low intensity cultivation, (3) Plain with aeolian cover: moderately cultivated, (4) Plain: Moderately to intensively cultivated. The major soils in association were Typic Torripsamments/Ustipsamments/Ustorthents/Ustifluvents/Calciorthids and Natric Camborthids.     

Monthly rainfall prediction using wavelet regression and neural network: an analysis of 1901–2002 data,Assam, India

Rainfall is a principal element of the hydrological cycle and its variability is important from both the scientific as well as practical point of view. Wavelet regression (WR) technique is proposed and developed to analyze and predict the rainfall forecast in this study. The WR model is improved combining two methods, discrete wavelet transform and linear regression model. This study uses rainfall data from 21 stations in Assam, India over 102 years from 1901 to 2002. The calibration and validation performance of the models is evaluated with appropriate statistical methods. The root mean square errors (RMSE), N-S index, and correlation coefficient (R) statistics were used for evaluating the accuracy of the WR models. The accuracy of the WR models was then compared with those of the artificial neural networks (ANN) models. The results of monthly rainfall series modeling indicate that the performances of wavelet regression models are found to be more accurate than the ANN models.