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Dash N.B.,Indian Institute of Technology Kharagpur | Panda S.N.,Indian Institute of Technology Kharagpur | Remesan R.,University of Bristol | Sahoo N.,Water Technology Center for Eastern Region
Neural Computing and Applications

The accurate prediction of groundwater level is important for the efficient use and management of groundwater resources, particularly in sub-humid regions where water surplus in monsoon season and water scarcity in non-monsoon season is a common phenomenon. In this paper, an attempt has been made to develop a hybrid neural model (ANN-GA) employing an artificial neural network (ANN) model in conjunction with famous optimization strategy called genetic algorithms (GA) for accurate prediction of groundwater levels in the lower Mahanadi river basin of Orissa State, India. Three types of functionally different algorithm-based ANN models (viz. back-propagation (GDX), Levenberg-Marquardt (LM) and Bayesian regularization (BR)) were used to compare the strength of proposed hybrid model in the efficient prediction of groundwater fluctuations. The ANN-GA hybrid modeling was carried out with lead-time of 1 week and study mainly aimed at November and January months of a year. Overall, simulation results suggest that the Bayesian regularization model is the most efficient of the ANN models tested for the study period. However, a strong correlation between the observed and predicted groundwater levels was observed for all the models. The results reveal that the hybrid GA-based ANN algorithm is able to produce better accuracy and performance in medium and high groundwater level predictions compared to conventional ANN techniques including Bayesian regularization model. Furthermore, the study shows that hybrid neural models can offer significant implications for improving groundwater management and water supply planning in semi-arid areas where aquifer information is not available. © 2010 Springer-Verlag London Limited. Source

Mandal K.G.,Indian Institute of Science | Mandal K.G.,Water Technology Center for Eastern Region | Hati K.M.,Indian Institute of Science | Misra A.K.,Indian Institute of Science | And 2 more authors.
Irrigation Science

A 3-year study was carried out to assess the root biomass production, crop growth rate, yield attributes, canopy temperature and water-yield relationships in Indian mustard grown under combinations of irrigation and nutrient application for revealing the dynamic relationship of crop yield (Y) and seasonal evapotranspiration (ET). Three post-sowing irrigation treatments viz. no irrigation (I 1), one irrigation at flowering (I 2) and two irrigations one each at rosette and flowering stage (I 3), three nutrient treatments viz. no fertilizer or manure (F 1), 100% recommended NPK i. e., 60 kg N, 13. 1 kg P and 16. 6 kg K ha -1 (F 2) and 100% recommended NPK plus farmyard manure @ 10 Mg ha -1 (F 3) were tested in a split-plot design. Root biomass was significantly greater in I 3 than I 2 and I 1, and in F 3 than F 2 and F 1. The I 3 × F 3, I 2 × F 3 and I 3 × F 2 combinations maintained significantly greater crop growth rate, plant height, yield components, ET and crop yield and better plant water status in terms of canopy temperature, canopy-air temperature difference (CATD) and relative leaf water content (RLWC). Number of siliqua plant -1 and seeds siliqua -1 were the major contributors to the seed yield. Marginal analysis of water production function was used to establish Y-ET relationship. The elasticity of water production (E wp) provides a means to assess relative changes in Y and ET, and gives an indication of improvement of Y due to nutrient application. The ET-Y relationships were linear with marginal water use efficiency (WUE m) of 3. 09, 4. 23 and 3. 95 kg ha -1 mm -1 in F 1, F 2 and F 3, respectively, and the corresponding E wp were 0. 63, 0. 71 and 0. 61. This implies that the scope for improving yield and WUE with 100% NPK was little compared with 100% NPK + farmyard manure. The crop yield was highest in I 3 × F 3 combination, and the similar yield was obtained in I 2 × F 3 and I 3 × F 2 combinations. Application of organic manure along with 100% NPK fertilizers maintained greater crop growth rate, better water relation in plants, yield attributes and saved one post-sowing irrigation. © 2009 Springer-Verlag. Source

Mohapatra A.,Fakir Mohan University | Mohanty R.K.,Water Technology Center for Eastern Region | Mohanty S.K.,Fisheries Consultant | Dey S.K.,Fakir Mohan University
Indian Journal of Marine Sciences

Carapace width (CW)-weight relationship, condition factor (K), relative condition factor (Kn) and gonado-somatic index (GSI) for meaty and post-moulted crabs of both sexes of the two mud crab species, Scylla serrata (Forskal) and S. tranquebarica (Fabricius) co-existing in Chilika lagoon, Orissa, India, were studied during August, 2005 to July, 2007. CW-weight equations and correlation co-efficient (r) obtained for both sexes of meaty and water crabs of the two species were significant (P< 0.05-0.01). Regression slopes (b) were higher for males and fattened crabs in both the species. The K and Kn values recorded in each month for different size groups of both sexes of the two species were higher in male and values were relatively higher in S. tranquebarica than S. serrata. Increase in Kn values beyond 1.0 from 81-91 mm CW in S. serrata and 111-120 mm CW in S. tranquebarica indicated the size at first maturity. Higher monthly values indicated that breeding period was extended from August-November and March-July in S. serrata and S. tranquebarica respectively. Species-specific study aimed at establishing difference in biological characters between two species of Scylla[a'] from same brackishwater habitat. CW-weight relationship may be useful in setting feeding rates for a particular species in aquaculture. Source

Kar G.,Water Technology Center for Eastern Region | Kumar A.,Water Technology Center for Eastern Region
Irrigation Science

In eastern India, cultivation of winter maize is getting popular after rainy season rice and farmers practice irrigation scheduling of this crop based on critical phenological stages. In this study, crop water stress index of winter maize at different critical stages wase determined to investigate if phenology-based irrigation scheduling could be optimized further. The components of the energy budget of the crop stand were computed. The stressed and non-stressed base lines were also developed (between canopy temperature and vapor pressure deficit) and with the help of base line equation, [(Tc - Ta) = -1. 102 VPD - 3. 772], crop water stress index (CWSI) was determined from the canopy-air temperature data collected frequently throughout the growing season. The values of CWSI (varied between 0. 42 and 0. 67) were noted just before the irrigations were applied at critical phenological stages. The soil moisture depletion was also measured throughout the crop growing period and plotted with CWSI at different stages. Study revealed that at one stage (silking), CWSI was much lower (0. 42-0. 48) than that of recommended CWSI (0. 60) for irrigation scheduling. Therefore, more research is required to further optimize the phenology-based irrigation scheduling of winter maize in the region. This method is being used now by local producers. The intercepted photosynthetically active radiation and normalized difference vegetation index over the canopy of the crop were also measured and were found to correlate better with leaf area index. © 2009 Springer-Verlag. Source

Rai D.R.,Punjab Agricultural University | Singh R.,Water Technology Center for Eastern Region
Journal of Food Process Engineering

Baby corn is highly perishable and requires appropriate postharvest technologies such as modified atmosphere packaging (MAP) to extend its shelf ife and maintain the nutritional content. However, MAP requires repetitive experimentation to arrive at suitable desired in-pack partial pressures of O 2 and CO 2 for application of appropriate MAP mode viz. nonperforated, macroperforated or microperforated one. Microperforated MAP is an expensive proposition and so far has limited commercial applicability, except for high-value commodities; therefore, macroperforated MAP is being tried to achieve higher gaseous diffusion across the film packages. Predictive modeling represents a physical phenomenon by means of mathematical equations; whose numerical solution can reliably predict transient and steady-state parameters in a dynamic system and can avoid the need of repetitive experimentation. However, representation of the respiratory behavior of a crop is also of utmost importance as wrong selection or very straightforward assumptions can lead to inadequate predictions. In this study, the respiratory behavior and associated inhibition by CO 2 as per established enzyme kinetics theory was first assessed within the temperature range of 5-15C for baby corn; which was then used to model-predict the in-pack partial pressures of O 2 and CO 2 at 10 and 15C; in nonperforated and macroperforated polypropylene film packages; utilizing baby corn, polymeric film, package and the storage environment parameters as input. Model validation during actual storage at 10 and 15C indicated that the model-predicted, in-pack partial pressures of O 2 and CO 2 agreed fairly well with the experimental observations at the selected temperatuers, which showed the appropriateness of the evaluated inhibitory mechanism of headspace CO 2. © 2011 Wiley Periodicals, Inc. Source

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