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Thawale P Ghosh T Kumar Singh S Singh S Kulkarni A 《Environmental monitoring and assessment》2012,184(4):2575-2591
Feasibility of an irrigation project is evaluated by two criteria viz., reservoir capacity to irrigate its command area and
economic returns by incremental crop production versus capital investment for dam construction. The annual water requirement
of different crops in the command area is estimated and compared with the availability of water from the dam for irrigation
purpose. The annual crop water requirement is estimated as the sum of evapotranspiration for crops and transmission and other
losses. Evapotranspiration is estimated by modified Penman formula. Economics of crop production is analyzed by first estimating
the monetary value of existing crop production under current rain fed conditions and then estimating the incremental production
of irrigated command area for the proposed crop pattern. The proposed cropping pattern is prepared so as to maximize the benefit
of crop production and fodder requirement while maintaining a better crop rotation to improve and maintain physical, chemical,
and biological conditions of the soil. The dam is to be used for irrigation and water supply only. Command area served by
this reservoir will be 76,500 ha. The existing annual agricultural return is Rs. 2995.56 lakhs and with the proposed irrigation
scheme, it is estimated as Rs. 1,77,91.90 lakhs. The incremental annual return would be Rs. 1,47,96.35 lakhs i.e., 642.68%
increase in annual return. 相似文献
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Sharma Prashant K. Raghubanshi Akhilesh S. Shah Kavita 《Environmental science and pollution research international》2021,28(11):13439-13453
Environmental Science and Pollution Research - The synthesized α-MoO3 and MoS2 NPs had nanosheet and nanoflower-like structures with crystallite size of 21.34 nm and 4.32 nm, respectively. The... 相似文献
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ABSTRACT In this paper, an artificial neural network-based control strategy is proposed for low voltage DC microgrid (LVDC microgrid) with a hybrid energy storage system (HESS) to improve power-sharing between battery and supercapacitor (SC) to suit the demand-generation imbalance, maintain state-of-charge (SOC) within boundaries and thereby to regulate the dc bus voltage. The conventional controller cannot track the SCs current rapidly with the high-frequency component that will place dynamic stress on the battery, further resulting in shorter battery life. The significant advantage is that in the proposed control strategy, redirections of unwaged battery currents to SCs for fast compensations enhance battery life span. The proposed control strategy effectiveness was investigated by simulations, including a comparison of overshoot/undershoot and settling time in dc bus voltage with a conventional control strategy. The results have been experimentally verified by hardware-in-loop (HIL) on a field-programmable gate array (FPGA)-based real-time simulator. 相似文献
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Prashant Kumar Andrew Garmory Matthias Ketzel Ruwim Berkowicz Rex Britter 《Atmospheric environment (Oxford, England : 1994)》2009,43(4):949-958
This study presents a comparison between measured and modelled particle number concentrations (PNCs) in the 10–300 nm size range at different heights in a canyon. The PNCs were modelled using a simple modelling approach (modified Box model, including vertical variation), an Operational Street Pollution Model (OSPM) and Computational Fluid Dynamics (CFD) code FLUENT. All models disregarded any particle dynamics. CFD simulations have been carried out in a simplified geometry of the selected street canyon. Four different sizes of emission sources have been used in the CFD simulations to assess the effect of source size on mean PNC distributions in the street canyon. The measured PNCs were between a factor of two and three of those from the three models, suggesting that if the model inputs are chosen carefully, even a simplified approach can predict the PNCs as well as more complex models. CFD simulations showed that selection of the source size was critical to determine PNC distributions. A source size scaling the vehicle dimensions was found to better represent the measured PNC profiles in the lowest part of the canyon. The OSPM and Box model produced similar shapes of PNC profile across the entire height of the canyon, showing a well-mixed region up to first ≈2 m and then decreasing PNCs with increased height. The CFD profiles do correctly reproduce the increase from road level to a height of ≈2 m; however, they do not predict the measured PNC decrease higher in the canyon. The PNC differences were largest between idealised (CFD and Box) and operational (OSPM) models at upper sampling heights; these were attributed to weaker exchange of air between street and roof-above in the upper part of the canyon in the CFD calculations. Possible reasons for these discrepancies are given. 相似文献
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Prashant?HegdeEmail author Kimitaka?Kawamura H.?Joshi M.?Naja 《Environmental science and pollution research international》2016,23(7):6102-6118
The aerosol samples were collected from a high elevation mountain site, Nainital, in India (1958 m asl) during September 2006 to June 2007 and were analyzed for water-soluble inorganic species, total carbon, nitrogen, and their isotopic composition (δ13C and δ15N, respectively). The chemical and isotopic composition of aerosols revealed significant anthropogenic influence over this remote free-troposphere site. The amount of total carbon and nitrogen and their isotopic composition suggest a considerable contribution of biomass burning to the aerosols during winter. On the other hand, fossil fuel combustion sources are found to be dominant during summer. The carbon aerosol in winter is characterized by greater isotope ratios (av. ?24.0?‰), mostly originated from biomass burning of C4 plants. On the contrary, the aerosols in summer showed smaller δ13C values (?26.0?‰), indicating that they are originated from vascular plants (mostly of C3 plants). The secondary ions (i.e., SO4 2?, NH4 +, and NO3 ?) were abundant due to the atmospheric reactions during long-range transport in both seasons. The water-soluble organic and inorganic compositions revealed that they are aged in winter but comparatively fresh in summer. This study validates that the pollutants generated from far distant sources could reach high altitudes over the Himalayan region under favorable meteorological conditions. 相似文献
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Environmental Chemistry Letters - Pillared interlayered clays have interesting properties such as high surface area, pore volume and extended pore size, high thermal stability, strong surface... 相似文献
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Fielding KS Terry DJ Masser BM Bordia P Hogg MA 《Journal of environmental management》2005,77(1):12-21
Water quality is a key concern in the current global environment, with the need to promote practices that help to protect water quality, such as riparian zone management, being paramount. The present study used the theory of planned behaviour as a framework for understanding how beliefs influence decisions about riparian zone management. Respondents completed a survey that assessed their behavioural, normative, and control beliefs in relation to intentions to manage riparian zones on their property. The results of the study showed that, overall, landholders with strong intentions to manage their riparian zones differed significantly in terms of their beliefs compared to landholders who had weak intentions to manage their riparian zones. Strong intentions to manage riparian zones were associated with a favourable cost-benefit analysis, greater perceptions of normative support for the practice and lower perceptions of the extent to which barriers would impede management of riparian zones. It was also evident that willingness to comply with the recommendations of salient referents, beliefs about the benefits of riparian zone management and perceptions of the extent to which barriers would impede riparian zone management were most important for determining intentions to manage riparian zones. Implications for policy and extension practice are discussed. 相似文献