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Laxmi Narayan Sethi

Bio: Laxmi Narayan Sethi is an academic researcher from Assam University. The author has contributed to research in topics: Water resources & Conjunctive use. The author has an hindex of 6, co-authored 15 publications receiving 254 citations. Previous affiliations of Laxmi Narayan Sethi include Indian Institute of Technology Kharagpur.

Papers
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Journal ArticleDOI
TL;DR: In this paper, the authors developed deterministic linear programming and chance-constrained linear programming (CCLP) models to allocate available land and water resources optimally on seasonal basis so as to maximize the net annual return from the study area.

125 citations

Journal ArticleDOI
TL;DR: In this article, two models have been developed viz. groundwater balance model and optimum cropping and groundwater management model to determine the optimal cropping pattern and allocation from private and government tubewells according to different soil types (saline and non-saline), type of agriculture (rainfed and irrigated) and seasons (monsoon and winter).
Abstract: Due to increasing trend of intensive rice cultivation in a coastal river basin, crop planning and groundwater management are imperative for the sustainable agriculture. For effective management, two models have been developed viz. groundwater balance model and optimum cropping and groundwater management model to determine optimum cropping pattern and groundwater allocation from private and government tubewells according to different soil types (saline and non-saline), type of agriculture (rainfed and irrigated) and seasons (monsoon and winter). A groundwater balance model has been developed considering mass balance approach. The components of the groundwater balance considered are recharge from rainfall, irrigated rice and non-rice fields, base flow from rivers and seepage flow from surface drains. In the second phase, a linear programming optimization model is developed for optimal cropping and groundwater management for maximizing the economic returns. The models developed were applied to a portion of coastal river basin in Orissa State, India and optimal cropping pattern for various scenarios of river flow and groundwater availability was obtained.

86 citations

Journal ArticleDOI
TL;DR: In this paper, four different drying methods viz. integrated drying system (IDS), fluidized bed dryer (FBD), electrical oven (EO) and open sun drying (OSD) were selected for comparative study of textural and color changes of ginger and turmeric.
Abstract: Spices are more preferred in powdered form and this invariably demands drying without compromising its quality attributes before grinding. Four different drying methods viz. integrated drying system (IDS), fluidized bed dryer (FBD), electrical oven (EO) and open sun drying (OSD) were selected for comparative study of textural and color changes of ginger and turmeric. The texture values of ginger differed significantly among different drying methods. Minimum crushing strength of 1,124.597 g (IDS) and highest of 1,421.62 g (OSD) was observed. Turmeric dried in IDS reflected maximum (8,789.01 g) and dried in EO showed minimum (6,307.619 g) crushing strength. Color loss values in dried ginger was minimum in IDS (34.795) followed by OSD (32.214), EO (37.479) and FBD (38.131), respectively. Color of dried turmeric was affected maximum in EO (67.354) followed by FBD (61.001) and OSD (58.213). Minimum color loss was observed in IDS (52.681). Instrumental measurement of texture and color attributes showed spices dried in IDS retained best quality attributes among the selected methods. Practical Applications The developed solar-biomass integrated drying system, apart from advantage of independence from grid power dependency, could safely be promoted for drying of ginger and turmeric to the stakeholders as evident from the comparative instrumental measurement study of texture and color attributes of the dried products.

32 citations

Journal ArticleDOI
TL;DR: Experimental validation confirmed the adequacy of the coating formulation for tomato optimized by response surface methodology with 2.15% chitosan and 0.50% glycerol.
Abstract: In the present work experiments were carried out to optimize coating formulation in central composite rotatable design varying chitosan and glycerol concentration from 0.5 to 3% (w/w) and 0 to 3% (w/w) respectively as two independent factors. Total color difference and respiration rate was selected for tomato parameters and water vapor permeability and percentage solubility was selected for coating parameters as response. Quadratic polynomial models generated was adequate to explain the effects of the chitosan and glycerol concentrations on response variables. Experimental validation confirmed the adequacy of the coating formulation for tomato optimized by response surface methodology with 2.15% chitosan and 0.50% glycerol. Characterization of the optimized coating was undertaken in scanning electron microscope, X-ray diffraction (XRD) and Fourier transform infra-red (FTIR) spectroscopy. Microstructure image revealed proper continuity, integrity and surface micro structure of the developed coating. XRD and FTIR spectra revealed the pattern of ideal chitosan based coatings and also unfolded various crystallographic, structural and molecular involvement and couplings in coating properties. XRD pattern reflected semicrystalline structure of chitosan based developed edible coating having crystal form-1 and crystal form-II. In addition to other expected ideal peaks, FTIR also confirmed the presence of water in the coating. Residual acetic acid (solvent for coating formulation) is also evident at around 1700 cm−1 of FTIR spectra, corresponding to carbonyl vibration of the carboxylic acid.

20 citations

Journal ArticleDOI
TL;DR: In this paper, a natural convection solar-biomass integrated drying system (IDS) was designed and developed, which was capable of generating adequate and continuous flow of hot air of temperature between 55 and 60C from ambient temperature of 28-30C during experimentation.
Abstract: Drying of food product helps in reducing the water activity of the farm product to a level below which deterioration does not occur for a definite duration. Spices are invariably dried and used in powdered form. Turmeric is one of the main spices of India which is 80 % of the world's supply of commercial turmeric in fresh weight per year. A natural convection solar-biomass integrated drying system (IDS) was designed and developed. The system was capable of generating adequate and continuous flow of hot air of temperature between 55 and 60C from ambient temperature of 28-30C during experimentation. Blanched turmeric rhizomes were successfully dried. The moisture content was brought down to 6.68 % (db) from initial level of 831.09 % (db). Among different thin layer drying models tested, Page and Modified Page models were found as best fit, when simulation was done for all the drying data. The effective moisture diffusivity of turmeric was calculated as 1.667 × 10−9 m2s−1. Effective drying time in IDS was 14 h while in traditional open sun drying (OSD), the same was 25 h. Negligible effect of drying on curcumin content was observed during the study. Practical Applications Use of solar energy as well as bio-waste material simultaneously for drying purpose is an effective method of drying to reduce drying cost, provided quality is maintained. Use of a simulation model is an important tool for prediction of performance of drying systems. The work carried out established the quality retention of dried turmeric while satisfying widely accepted simulation models.

15 citations


Cited by
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Journal ArticleDOI
TL;DR: The comprehensive reviews on the use of various programming techniques for the solution of different optimization problems have been provided and conclusions are drawn where gaps exist and more research needs to be focused.

194 citations

Journal ArticleDOI
TL;DR: It is argued that cropping plan and crop rotation decisions are on the contrary dynamic processes incorporated into a succession of other planned and adaptive decisions made at annual and long-term horizons.
Abstract: Farmers must yearly allocate fields to different crops and choose crop management options. Far from being obvious, these decisions are critical because they modify farm productivity and profitability in the short and long run. To support farmers and efficiently allocate scarce resources, decision support models are developed. Decision support models are mainly based on two concepts, the cropping plan and the crop rotation decisions. These decisions concern crop choice, crop spatial distribution within the farmland and crop temporal successions over years. Decisions are at the core of the farm management. Decisions have strong impacts on resource use efficiency and on environmental processes at both farm and landscape scales. We review here more than 120 references where cropping plan and crop rotation decision concepts were incorporated into models. Our aim is to review how these two concepts have been formalised and used in agronomic, economic and land-use studies. We found that cropping plan decisions selection and design have been done using many approaches based on different objectives and handled at very different scales. The main results show that (1) cropping plan design decisions have mainly been tackled as a static concept, i.e. as if they were a single decision made only once a year or once a rotation; (2) modelling the achievement of a suitable cropping plan is often based on a single monetary criterion optimization procedure instead of a multi-criteria assessment; and (3) when considered, uncertainty of information is defined as stochastic factors or probability of occurrence, but this probability is kept static whatever the knowledge of the dynamic evolution of various constraints. We argue that cropping plan and crop rotation decisions are on the contrary dynamic processes incorporated into a succession of other planned and adaptive decisions made at annual and long-term horizons. For supporting farmers in their decisions, new cropping plan decision models will require new modelling paradigm. A promising improvement could be reached by including explicitly the simulation of the farmers' decision-making processes, based on the simulation of the decision-making processes rather than on single normative approaches.

194 citations

Posted Content
TL;DR: The mechanism of biosorption is complex, mainly ion exchange, chelation, adsorption by physical forces, entrapment in inter and intrafibrilliar capillaries and spaces of the structural polysaccharide network as a result of the concentration gradient and diffusion through cell walls and membranes as discussed by the authors.
Abstract: Metallic species mobilized and released into the environment by the technological activities of human tend to persist indefinitely, circulating and eventually accumulating throughout the food chain, thus posing a serious threat to the environment, animals and humans. It is essential to realize that the metal is only removed from solution when it is appropriately immobilized. Apart from slow natural process of metal mineralization, ultimate removal is attained only when the metal becomes concentrated to the point that it can be either returned to the process or resold. The metallic pollutants can be sorbed by biosorbant material. The mechanism of biosorption is complex, mainly ion exchange, chelation, adsorption by physical forces, entrapment in inter and intrafibrilliar capillaries and spaces of the structural polysaccharide network as a result of the concentration gradient and diffusion through cell walls and membranes. Due to the extensive research and significant economic benefits of biosorption, some new biosorbant resources are poised for commercial exploitation.

176 citations

Journal ArticleDOI
TL;DR: In this article, the performance of a mixed mode forced convection solar dryer integrated with paraffin wax based thermal energy storage has been studied for drying the sliced black turmeric (curcuma caesia).

147 citations

Journal ArticleDOI
10 May 2007
TL;DR: In this paper, the authors used a variable density flow and solute transport model, SUTRA, to define the current and potential extent of seawater intrusion in the Burdekin Delta under various pumping and recharge conditions.
Abstract: The Burdekin Delta is a major irrigation area situated in the dry tropics of North Queensland. It is unique in that (i) it overlies shallow groundwater systems that serve as a major water supply for the irrigation of sugarcane, and (ii) it is adjacent to the world heritage listed Great Barrier Reef. Water management practices include large recharge pits and surface spreading of water to assist with replenishment of the groundwater. This has been useful in maintaining groundwater levels to help control seawater intrusion. This technique, however, can be costly and ineffective in unconfined aquifer systems, which are subjected to large amounts of groundwater pumping for irrigation. There are more than 1800 production bores currently used for irrigation in the Burdekin Delta and the large volumes of water extracted have at times lowered the regional water tables and made it difficult to control seawater intrusion. In this paper we describe the use of a variable density flow and solute transport model, SUTRA, to define the current and potential extent of seawater intrusion in the Burdekin Delta under various pumping and recharge conditions. A 2D vertical cross-section model, which accounts for groundwater pumping and recharge, was developed for the area. The Burdekin Delta aquifer consists mainly of sand and clay lenses with granitic bedrock. The model domain uses vertical cross-sections along the direction of groundwater flow. The initial conditions used in the model are based on land use prior to agricultural development when the seawater wedge was in its assumed natural state. Results of this study demonstrate the effects of variations in pumping and net recharge rates on the dynamics of seawater intrusion. Simulations have been carried out for a range of recharge, pumping rates and hydraulic conductivity values. Modelling results show that seawater intrusion is far more sensitive to pumping rates and recharge than to aquifer properties such as hydraulic conductivity. Analysis also shows that the effect of tidal fluctuations on groundwater levels is limited to areas very close to the coast. Tidal influences on saltwater intrusion therefore can be neglected when compared with the effects due to groundwater pumping. The impacts of various management options on groundwater quality are also discussed.

134 citations