2,479 research outputs found

    Per Capita Income – Based on Sangam Era

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    Porunar, Pulavar, Panar, Koudhar, Patini, Varaviyar are known as Iravalars (beggers). They are called as Iravalars because they earn their living by singing. In their songs, they praise the rich people and as gift, they get gifts, money and so on. The rich people also go in search of Iravalars, because they love to hear their songs in praise of them. Sangha literary texts speaks abundantly and extensively about the people living as Iravalars and how they earn their income by singing praise of others

    System Identification Using Orthonormal Basis Filters

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    Process Analysis and Selection for The Production of P-Cumidine

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    P-cumidine is very important intermediate for many chemical and agrochemical industries. The product, Para cumidine is versatile chemical intermediate that has applications in dyes, pharmaceuticals, and herbicides. The major use of para cumidine as an intermediate in the manufacturing of isoproterenol which is a selective herbicide belonging to the family of substituted ureas and acts principally after root absorption, either pre-emergence or post-emergence. There are many different processes from which p-cumidine can be manufactured. But industrially used process is nitration of cumene followed by hydrogenation. The processes for manufacturing of p-cumidine are alkylation of aniline, nitration of cumene followed by hydrogenation, nitration of cumene followed by reduction using caustic lye and Sulphur. But industrially used process is nitration of cumene followed by hydrogenation

    Artificial Neural Network Optimization Modeling On Engine Performance Of Diesel Engine Using Biodiesel Fuel

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    This paper presents a study of engine performance using a mixture of palm oil methyl ester blends with diesel oil as biodiesel in a diesel engine, and optimizes the engine performance using artificial neural network (ANN) modeling. To acquire data for training and testing of the proposed ANN, a four-cylinder, four-stroke diesel engine was fuelled with different palm oil methyl ester blends as biodiesel, operated at different engine loads. The properties of biodiesel produced from waste vegetable oil were measured based on ASTM standards. The experimental results revealed that blends of palm oil methyl ester with diesel fuel provided better engine performance. An ANN model was developed based on the Levenberg-Marquardt algorithm for the engine. Logistic activation was used for mapping between the input and output parameters. It was observed that the ANN model could predict the engine performance quite well with correlation coefficients (R) of 0.996684, 0.999, 0.98964 and 0.998923 for the incylinder pressure, heat release, thermal efficiency, and volume, respectively. The predicted MSE (mean square error) error was between the desired outputs, as the measured and simulated values were obtained as 0.0001 by the model. Long-term effects on engine performance when running on biodiesel fuel can be further studied and improved

    System Identification Based Proxy Model of a Reservoir under Water Injection

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    Simulation of numerical reservoir models with thousands and millions of grid blocks may consume a significant amount of time and effort, even when high performance processors are used. In cases where the simulation runs are required for sensitivity analysis, dynamic control, and optimization, the act needs to be repeated several times by continuously changing parameters. This makes it even more time-consuming. Currently, proxy models that are based on response surface are being used to lessen the time required for running simulations during sensitivity analysis and optimization. Proxy models are lighter mathematical models that run faster and perform in place of heavier models that require large computations. Nevertheless, to acquire data for modeling and validation and develop the proxy model itself, hundreds of simulation runs are required. In this paper, a system identification based proxy model that requires only a single simulation run and a properly designed excitation signal was proposed and evaluated using a benchmark case study. The results show that, with proper design of excitation signal and proper selection of model structure, system identification based proxy models are found to be practical and efficient alternatives for mimicking the performance of numerical reservoir models. The resulting proxy models have potential applications for dynamic well control and optimization

    The evolution of Bordetella pertussis has selected for mutations of acr that lead to sensitivity to hydrophobic molecules and fatty acids

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    Whooping cough, or pertussis, is resurgent in numerous countries worldwide. This has renewed interest in Bordetella pertussis biology and vaccinology. The in vitro growth of B. pertussis has been a source of difficulty, both for the study of the organism and the production of pertussis vaccines. It is inhibited by fatty acids and other hydrophobic molecules. The AcrAB efflux system is present in many different bacteria and in combination with an outer membrane factor exports acriflavine and other small hydrophobic molecules from the cell. Here, we identify that the speciation of B. pertussis has selected for an Acr system that is naturally mutated and displays reduced activity compared to B. bronchiseptica, in which the system appears intact. Replacement of the B. pertussis locus with that of B. bronchiseptica conferred higher levels of resistance to growth inhibition by acriflavine and fatty acids. In addition, we identified that the transcription of the locus is repressed by a LysR-type transcriptional regulator. Palmitate de-represses the expression of the acr locus, dependent on the LysR regulator, strongly suggesting that it is a transcriptional repressor that is regulated by palmitate. It is intriguing that the speciation of B. pertussis has selected for a reduction in activity of the Acr efflux system that typically is regarded as protective to bacteria

    Cable properties and propagation velocity in a long single chain of simulated myocardial cells

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    <p>Abstract</p> <p>Background</p> <p>Propagation of simulated action potentials (APs) was previously studied in short single chains and in two-dimensional sheets of myocardial cells <abbrgrp><abbr bid="B1">1</abbr><abbr bid="B2">2</abbr><abbr bid="B3">3</abbr></abbrgrp>. The present study was undertaken to examine propagation in a long single chain of cells of various lengths, and with varying numbers of gap-junction (g-j) channels, and to compare propagation velocity with the cable properties such as the length constant (<it>λ</it>).</p> <p>Methods and Results</p> <p>Simulations were carried out using the PSpice program as previously described. When the electric field (EF) mechanism was dominant (0, 1, and 10 gj-channels), the longer the chain length, the faster the overall velocity (<it>θ</it><sub>ov</sub>). There seems to be no simple explanation for this phenomenon. In contrast, when the local-circuit current mechanism was dominant (100 gj-channels or more), <it>θ</it><sub>ov </sub>was slightly slowed with lengthening of the chain. Increasing the number of gj-channels produced an increase in <it>θ</it><sub>ov </sub>and caused the firing order to become more uniform. The end-effect was more pronounced at longer chain lengths and at greater number of gj-channels.</p> <p>When there were no or only few gj-channels (namely, 0, 10, or 30), the voltage change (ΔV<sub>m</sub>) in the two contiguous cells (#50 & #52) to the cell injected with current (#51) was nearly zero, i.e., there was a sharp discontinuity in voltage between the adjacent cells. When there were many gj-channels (e.g., 300, 1000, 3000), there was an exponential decay of voltage on either side of the injected cell, with the length constant (<it>λ</it>) increasing at higher numbers of gj-channels. The effect of increasing the number of gj-channels on increasing <it>λ </it>was relatively small compared to the larger effect on <it>θ</it><sub>ov</sub>. <it>θ</it><sub>ov </sub>became very non-physiological at 300 gj-channels or higher.</p> <p>Conclusion</p> <p>Thus, when there were only 0, 1, or 10 gj-channels, <it>θ</it><sub>ov </sub>increased with increase in chain length, whereas at 100 gj-channels or higher, <it>θ</it><sub>ov </sub>did not increase with chain length. When there were only 0, 10, or 30 gj-channels, there was a very sharp decrease in ΔV<sub>m </sub>in the two contiguous cells on either side of the injected cell, whereas at 300, 1000, or 3000 gj-channels, the voltage decay was exponential along the length of the chain. The effect of increasing the number of gj-channels on spread of current was relatively small compared to the large effect on <it>θ</it><sub>ov</sub>.</p

    Intelligent Height and Reach Adjustable Electronic Chair for Children with Dwarfism (ZUMP)

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    "Dwarfism", "little people", "short statue" or even "midget" are some of the general names given by society to these special communities. According to the definition of the advocacy group for Little People of America (LPA), Dwarfism is a condition characterized by short stature. Technically, an adult with the height of 4 feet 10 inches or under. Based on the study on the dwarfism symptom, it can be caused by any one of more than 200 conditions, most of which are genetic. Most types of dwarfism are known as skeletal dysplasias, which are conditions of abnormal bone growth. In fact, 85% of children with skeletal dyplasias do occur in families where both parents are of average height. Being a dwarfism is not an intellectual disability. A person who has dwarfism is typically of normal intelligence. Somehow, dwarfism is a disease that requires a "cure". Most people with the condition can live long and fulfilling lives. Lastly, it will not be good reason to assume dwarfism is incapable. Little people go to school, go to work, marry, and raise children, just like their average-size peers

    Scalable fabrication of gap-plasmon-based dynamic and chromogenic nanostructures by capillary-interaction driven self-assembly of liquid-metal

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    Dynamically tunable nanoengineered structures for coloration show promising applications in sensing, displays, and communication. However, their potential challenge remains in having a scalable manufacturing process over large scales in tens of cm of area. For the first time, we report a novel approach for fabricating chromogenic nanostructures that respond to mechanical stimuli by utilizing the fluidic properties of polydimethylsiloxane (PDMS) as a substrate and the interfacial tension of liquid metal-based plasmonic nanoparticles. Relying on the PDMS tunable property and a physical deposition method, our approach is single-step, scalable, and does not rely on high carbon footprint lithographic processes. By tuning the oligomer content in PDMS, we show that varieties of structural colors covering a significant gamut in CIE coordinates are achieved. We develop a model which depicts the formation of Ga nanodroplets from the capillary interaction of oligomers in PDMS with Ga. We showcase the capabilities of our processing technique by presenting prototypes of reflective displays and sensors for monitoring body parts, smart bandages, and the capacity of the nanostructured film to map force in real time. These examples illustrate this technology's broad range of applications, such as large-area displays, devices for human-computer interactions, healthcare, and visual communication
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