6,372 research outputs found

    A system-level mathematical model for evaluation of power train performance of load-leveled electric-vehicles

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    The power train performance of load leveled electric vehicles can be compared with that of nonload leveled systems by use of a simple mathematical model. This method of measurement involves a number of parameters including the degree of load leveling and regeneration, the flywheel mechanical to electrical energy fraction, and efficiencies of the motor, generator, flywheel, and transmission. Basic efficiency terms are defined and representative comparisons of a variety of systems are presented. Results of the study indicate that mechanical transfer of energy into and out of the flywheel is more advantageous than electrical transfer. An optimum degree of load leveling may be achieved in terms of the driving cycle, battery characteristics, mode of mechanization, and the efficiency of the components. For state of the art mechanically coupled flyheel systems, load leveling losses can be held to a reasonable 10%; electrically coupled systems can have losses that are up to six times larger. Propulsion system efficiencies for mechanically coupled flywheel systems are predicted to be approximately the 60% achieved on conventional nonload leveled systems

    Second-generation Biofuel Potential in India: Sustainability and Cost Considerations

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    This study is part of a larger research project on "Promoting Low-Carbon Transport in India", a major initiative of the United Nations Environment Programme (UNEP), hereafter referred to as the Low Carbon Transport (LCT) project in this document. The overall context in which the LCT project has been undertaken is the critical role of the transport sector in reducing greenhouse gas (GHG) emissions. India is currently the fourth largest GHG emitter in the world, although its per capita emissions are less than half the world's average. Furthermore, India's transport sector accounts for 13 percent of the country's energy related CO2 emissions. It is evident that opportunities exist to make India's transport growth more sustainable by aligning development and climate change agendas. At present, India is pursuing a comprehensive set of policies to move the country to a low-carbon growth path. In 2009, India announced that it would reduce the emissions intensity of its gross domestic product (GDP) by 20 percent to 25 percent over the 2005 levels by the year 2020. Specific measures to attain these goals are also being developed through the national missions identified in the National Action Plan on Climate Change (NAPCC) of 2008. The NAPCC recognises that GHG emissions from transport can be reduced by adopting a sustainability approach through a combination of measures such as increased use of public transport, higher penetration of bio-fuels, and enhanced energy efficiency of transport vehicles

    Utilization of waste heat in trucks for increased fuel economy

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    Improvements in fuel economy for a broad spectrum of truck engines and waste heat utilization concepts are evaluated and compared. The engines considered are the diesel, spark ignition, gas turbine, and Stirling. The waste heat utilization concepts include preheating, regeneration, turbocharging, turbocompounding, and Rankine engine compounding. Predictions were based on fuel-air cycle analyses, computer simulation, and engine test data. The results reveal that diesel driving cycle performance can be increased by 20% through increased turbocharging, turbocompounding, and Rankine engine compounding. The Rankine engine compounding provides about three times as much improvement as turbocompounding but also costs about three times as much. Performance for either is approximately doubled if applied to an adiabatic diesel

    Future fuels and engines for railroad locomotives. Volume 1: Summary

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    The potential for reducing the dependence of railroads on petroleum fuel, particularly Diesel No. 2 was investigated. Two approaches are studied: (1) to determine how the use of Diesel No. 2 can be reduced through increased efficiency and conservation, and (2) to use fuels other than Diesel No. 2 both in Diesel and other types of engines. Because synthetic hydrocarbon fuels are particularly suited to medium speed diesel engines, the first commercial application of these fuels may be by the railroad industry

    What is Information Worth for an Extra Quintal of Grain?: Randomised Experimental Evidence from Farmers in India

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    This study evaluates whether access to real-time customised idiosyncratic agricultural information over extended seasons improves the value of such information among farmers. We conduct a controlled randomised experiment in the Indian state of Karnataka. The study employs the difference-in-difference method to a panel of households comparing the differential valuation of information during the post-intervention period between treatment (participant) and control (non-participant) farmers relative to the outcomes observed during a pre-intervention period. We find robust evidence of the intervention showing significantly positive impacts on the valuation of agricultural information among treatment farmers relative to the control farmers. A difference of each one unit improvement in information access is found to be associated with 53 percent average increase in the mean valuation of the information. The result indicates that farmers value information that is comprehensive, reliable, real-time and idiosyncratic as opposed to the more generic or piecemeal information

    ACCURACY OF FNAC IN FEMALE BREAST LESIONS

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    Background: Various breast lesions are common lesions in females with a wide range of variability from inflammatory lesions, benign and malignant breast lesions. FNAC is first diagnostic test, as it has high sensitivity and specificity. Lesions were categorized on FNA into inflammatory lesions, benign neoplastic lesions, malignant neoplastic lesions, and suspicious for malignancy. Methods: This was a retrospective study done in the Department of Pathology, P.D.U. Medical College, Rajkot, Gujarat State, India from Aug-2013 to July 2014. FNAC of 392 cases of breast lesions were done and reported by expert pathologist. The histopathological specimens when available were reported by other pathologist without prior knowledge of FNA diagnosis. Sensitivity, Specificity and Accuracy of FNA diagnosis were then analyzed. Results: A total of 392 cases of breast lesions were diagnosed on FNA, out of them histopathological correlation was available in 87 cases. Benign breast lesions are more common in younger patients in 21-30 yrs age group and malignant lesions are more common in old age group patients of 41-60 yrs with few exceptions. In our setup fibroadenoma is the most common benign breast lesion (26.53%) and ductal carcinoma (17.86%) is the most common malignant lesion. The sensitivity, specificity and accuracy of FNAC for malignant lesions were found to be 91.43%, 100% and 96.25% respectively. Conclusion: FNAC is an effective and valid tool as the first line diagnostic modality in the preoperative diagnosis of the malignant and benign breast lesions.KEYWORDS: FNAC; Breast lesions; Fibroadenoma; Ductal carcinoma

    ACCURACY OF FNAC IN FEMALE BREAST LESIONS

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    Background: Various breast lesions are common lesions in females with a wide range of variability from inflammatory lesions, benign and malignant breast lesions. FNAC is first diagnostic test, as it has high sensitivity and specificity. Lesions were categorized on FNA into inflammatory lesions, benign neoplastic lesions, malignant neoplastic lesions, and suspicious for malignancy. Methods: This was a retrospective study done in the Department of Pathology, P.D.U. Medical College, Rajkot, Gujarat State, India from Aug-2013 to July 2014. FNAC of 392 cases of breast lesions were done and reported by expert pathologist. The histopathological specimens when available were reported by other pathologist without prior knowledge of FNA diagnosis. Sensitivity, Specificity and Accuracy of FNA diagnosis were then analyzed. Results: A total of 392 cases of breast lesions were diagnosed on FNA, out of them histopathological correlation was available in 87 cases. Benign breast lesions are more common in younger patients in 21-30 yrs age group and malignant lesions are more common in old age group patients of 41-60 yrs with few exceptions. In our setup fibroadenoma is the most common benign breast lesion (26.53%) and ductal carcinoma (17.86%) is the most common malignant lesion. The sensitivity, specificity and accuracy of FNAC for malignant lesions were found to be 91.43%, 100% and 96.25% respectively. Conclusion: FNAC is an effective and valid tool as the first line diagnostic modality in the preoperative diagnosis of the malignant and benign breast lesions.KEYWORDS: FNAC; Breast lesions; Fibroadenoma; Ductal carcinoma

    Concentrating solar power

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    Adoption of Improved Cultivars of Pearl Millet in an Arid Environment: Straw Yield and Quality Considerations in Western Rajasthan

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    The role of straw yield and quality in farmers' decisions about the adoption of pearl millet cultivars in western Rajasthan was examined using farm household surveys. Information on the relative importance of grain versus straw yield, the perceived risks associated with the use of new cultivars under variable climatic conditions and perceptions of straw quality indicated that improved cultivars of pearl millet were not adopted primarily because of poor grain yield in years with low rainfall, though poor straw yield in such years was also important. These results are particularly pertinent in the light of farmers' perceptions of the likelihood of experiencing drought or low rainfall. If new cultivars of pearl millet are to replace the traditional ones, they must perform better under conditions of limited rainfall

    Gating at the Mouth of the Acetylcholine Receptor Channel: Energetic Consequences of Mutations in the αM2-Cap

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    Gating of nicotinic acetylcholine receptors from a C(losed) to an O(pen) conformation is the initial event in the postsynaptic signaling cascade at the vertebrate nerve-muscle junction. Studies of receptor structure and function show that many residues in this large, five-subunit membrane protein contribute to the energy difference between C and O. Of special interest are amino acids located at the two transmitter binding sites and in the narrow region of the channel, where C↔O gating motions generate a low↔high change in the affinity for agonists and in the ionic conductance, respectively. We have measured the energy changes and relative timing of gating movements for residues that lie between these two locations, in the C-terminus of the pore-lining M2 helix of the α subunit (‘αM2-cap’). This region contains a binding site for non-competitive inhibitors and a charged ring that influences the conductance of the open pore. αM2-cap mutations have large effects on gating but much smaller effects on agonist binding, channel conductance, channel block and desensitization. Three αM2-cap residues (αI260, αP265 and αS268) appear to move at the outset of channel-opening, about at the same time as those at the transmitter binding site. The results suggest that the αM2-cap changes its secondary structure to link gating motions in the extracellular domain with those in the channel that regulate ionic conductance
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