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Sharma S.,Shri Govindram Seksaria Institute of Technology and Science | Singh B.,Indian Institute of Technology Delhi
IEEE Transactions on Industry Applications | Year: 2014

This paper deals with the implementation of a voltage and frequency controller (VFC) for an isolated asynchronous generator (IAG)-based stand-alone wind energy conversion system (SWECS) with a battery energy storage system (BESS) feeding three-phase four-wire loads. The control algorithm for VFC is based on a low-pass filter (LPF) for estimation of reference source currents. The VFC is realized using a voltage source converter (VSC) with a BESS at its dc bus and a nonisolated T-connected transformer to feed three-phase four-wire consumer loads. Test results are presented to demonstrate the performance of a proposed VFC for an IAG in the wind power generation. © 2013 IEEE. Source


Singh B.,Indian Institute of Technology Delhi | Sharma S.,Shri Govindram Seksaria Institute of Technology and Science
IEEE Transactions on Industry Applications | Year: 2012

This paper deals with a stand-alone single-phase power generation using a three-phase isolated asynchronous generator (IAG) coupled with a wind turbine or a pico-hydro turbine. The proposed voltage and frequency controller (VFC) for a stand-alone single-phase power generation is used as a phase balancer for a three-phase IAG, a load leveler, and an active filter. The VFC is realized using a three-leg voltage-source converter and a battery energy storage system. The VFC ensures optimum utilization of a three-phase IAG for feeding a variety of single-phase loads, improves conversion efficiency, and reduces noise and vibration in the IAG. The rating considerations of an IAG and VFCs are also discussed for a single-phase power generation. The performance of an IAG system is demonstrated under steady-state and dynamic conditions of feeding single-phase linear and nonlinear loads. Simulated results are validated with test results on a developed system. © 1972-2012 IEEE. Source


Bhadauria S.S.,Shri Govindram Seksaria Institute of Technology and Science
Journal of Performance of Constructed Facilities | Year: 2014

Some rural water supply (RWS) schemes were constructed in 2002 in the Dhule district of Maharashtra State in India as part of pilot projects launched in 68 districts throughout the country with financial assistance from the Government of India. The present research is derived from an investigation conducted on 11 such RWS schemes constructed during the period of 2002-2005 and aims to establish a composite sustainable management index for assessing long-term sustainability in the context of the level of service and evaluating the current performance level of piped-water supply schemes. The identification of factors influencing sustainable management is a prerequisite for developing a composite index. Various investigators have worked on the sustainability of RWS systems worldwide considering different sets of factors and subfactors. In this research, a set of five factors and 25 subfactors is considered. Two factors, though being a part of functional sustainability, are excluded in building the index; however, they are used to validate the results. The analytical hierarchy process is used for the development of metrics in decision making, i.e., for establishing the weight of factors and subfactors. The proposed model enables RWS utilities to identify the key sustainable management factors and provides a framework for aggregating various factors and subfactors into a composite sustainable management index. The outcome may also be used to identify the factors/subfactors that have potential for improvement and thus be helpful in finalizing the strategies for enhancing the functional sustainability of the system. The results demonstrate that nine subfactors out of the 25 dominate in all 11 RWS utilities studied. The RWS utilities are classified on the basis of their performance as high, moderate, or low in sustainability. The derived factors' sustainability index may be useful for decision makers to discover the tradeoffs between them. The derived index may be a rational and transparent basis for recommending postconstruction support for a rural water utility. The limitations of the presented research are the comprehensiveness and effectiveness of the data considered, being slightly biased to the accessibility of information, in the absence of a more rational data-recording system. © 2014 American Society of Civil Engineers. Source


Singh V.,Shri Govindram Seksaria Institute of Technology and Science | Tiwari M.,Shri Govindram Seksaria Institute of Technology and Science
Asian Journal of Chemistry | Year: 2011

Chitosan is being investigated widely for use as an excipient in oral and other pharmaceutical formulations. Chitosan is generally regarded as a nontoxic and non-irritant material. It is biocompatible with both healthy and infected skin. Chitosan has been shown to be biodegradable (LD50 (mouse, oral): > 16 g/kg). Unmodified chitosan exhibited a low degree of disorder and a weak tablet crushing strength. In the present work, the hydrophobically modified chitosan were synthesized in order to formulate a system for sustain release of hydrophilic drug (indomethacine prototype drug in present case). The caproyl (C-8), decanoyl (C-10), lauryl (C-12), myristyl (C-14), palmitoyl (C-16) and stearoyl (C-18), fatty acyl derivatives of chitosan were prepared and physicochemically evaluated as excipient in matrix tablet dosage. The best sustained release studies was defined by palmitoyl chitosan and it can able sustain 50-60 % release upto 12 h and in concentration range 10-30 % much less as compared to chitosan ( > 50 %). Source


Srivastav V.K.,Shri Govindram Seksaria Institute of Technology and Science | Tiwari M.,Shri Govindram Seksaria Institute of Technology and Science
Medicinal Chemistry Research | Year: 2015

A three-dimensional quantitative structure activity relationship (3D-QSAR) study was carried out on a dataset of 62 cinnamoyl derivatives as human immunodeficiency virus-1 integrase (HIV-1 IN) inhibitors using k-nearest neighbor molecular field analysis (kNN-MFA). QSAR models were developed using stepwise-forward selection (SWF), genetic algorithm (GA), and simulated annealing (SA) variable selection approaches. Selected QSAR models were validated internally [using cross-validated squared correlation coefficient (q 2)] and externally [using predicted squared correlation coefficient (pred-r 2) and Y randomization] to determine their predictive ability. SA-kNN-MFA model (q 2 = 0.7669, pred-r 2 = 0.7566) was considered as the best model due to its better predictive ability (higher pred-r 2 value) as compared to SWF-kNN-MFA (q 2 = 0.8956, pred-r 2 = 0.5905) and GA-kNN-MFA (q 2 = 0.6431, pred-r 2 = 0.7525) models in external validation. Steric and electrostatic field descriptors were favorable for HIV-1 IN inhibition activity in the best model. HIV-1 IN inhibition activity of an external dataset containing 22 compounds was predicted to check the applicability domain of developed models. Drug-likeness and in silico absorption, distribution, metabolism, excretion, and toxicity (ADME/T) studies were also performed to determine the pharmacokinetic and toxicity profile of dataset compounds. Subsequently, HIV-1 IN inhibition activity of 53 proposed compounds was predicted using developed models and their ADME/T properties were also calculated. Results of the present study suggested that 3D-QSAR model developed by SA-kNN-MFA method may be helpful to understand the structural requirement for HIV-1 IN inhibition and may support the designing of potent antiretroviral agents. © 2014 Springer Science+Business Media New York. Source

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