397 research outputs found

    High-fidelity Simulation of Jet Noise from Rectangular Nozzles

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    This Phase II project validated a state-of-the-art LES model, coupled with a Ffowcs Williams-Hawkings (FW-H) far-field acoustic solver, to support the development of advanced engine concepts. These concepts include innovative flow control strategies to attenuate jet noise emissions. The end-to-end LES/ FW-H noise prediction model was demonstrated and validated by applying it to rectangular nozzle designs with a high aspect ratio. The model also was validated against acoustic and flow-field data from a realistic jet-pylon experiment, thereby significantly advancing the state of the art for LES

    IMPACT OF TANNERIES ON GROUND WATER CONTAMINATION IN UNNAO DISTRICT

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    Attempt is made to understand the impact of tanneries on ground water quality of Unnao. Study was undertaken to evaluate physico-chemical parameters and chromium, lead iron concentration in ground water near tannery industries. The results revealed that only two parameters fluoride and chromium are present in slight high concentration than permissible limit. Ground water quality % sample compliance / violation with respect to BIS standard were also studied

    Evaluating NIST Metric for English to Hindi Language Using ManTra Machine Translation Engine

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    Abstract: Evaluation of MT is required for Indian languages because the same MT is not works in Indian language as in European languages due to the language structure. So, there is a great need to develop appropriate evaluation metric for the Indian language MT. The present research work aims at studying the Evaluation of Machine Translation Evaluation's NIST metric for English to Hindi for tourism domain using the output of ManTra, a translation system. Machine Translation Evaluation has been widely recognized by the Machine Translation community. The main objective of MT is to break the language barrier in a multilingual nation like India

    Base Flow Model Validation

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    A method was developed of obtaining propulsive base flow data in both hot and cold jet environments, at Mach numbers and altitude of relevance to NASA launcher designs. The base flow data was used to perform computational fluid dynamics (CFD) turbulence model assessments of base flow predictive capabilities in order to provide increased confidence in base thermal and pressure load predictions obtained from computational modeling efforts. Predictive CFD analyses were used in the design of the experiments, available propulsive models were used to reduce program costs and increase success, and a wind tunnel facility was used. The data obtained allowed assessment of CFD/turbulence models in a complex flow environment, working within a building-block procedure to validation, where cold, non-reacting test data was first used for validation, followed by more complex reacting base flow validation

    Space Propulsion Design and Analysis

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    This software provides an improved methodology for predicting launcher base pressure and heat loads for RSRM (Reusable Solid Rocket Motor) launchers by accounting for complex anisotropic stress/strains and variable turbulent Prandtl and Schmidt numbers. A "building block" approach to turbulence model development, and validation has been applied for improved missile/launcher base region analysis. Modifications to existing kappa - epsilon turbulence models and application of scalar variance models are incorporated into a RANS-based method for aeropropulsive flow modeling, directly related to base flow methodology. (RANS stands for Reynolds-averaged Navier-Stokes.) The models are applied in a RANS solver framework and can improve analysis of other complex flow fields. The enhanced models provide a more accurate predictive capability for improving the design and analysis of RSRM launcher configuration. The kappa - epsilon model enhancements have been shown to improve the capability for predicting turbulence effects in base blow environments. The scalar variance models have been assessed over a wide range of flow configurations to improve prediction of turbulent scalar mixing

    Ensemble quantum-information processing by NMR: implementation of gates and the creation of pseudopure states using dipolar coupled spins as qubits

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    Quantum-information processing is carried out using dipolar coupled spins and high-resolution nuclear magnetic resonance (NMR). The systems chosen are the dipolar coupled methyl protons of CH3CN partially oriented in a liquid crystalline matrix yielding a two-qubit system and dipolar coupled 13C and methyl protons of 13CH3CN also partially oriented in the liquid crystalline matrix, yielding a three-qubit system. The dipolar coupled protons of oriented CH3 group are chemically and magnetically identical and their eigenstates can be divided into a set of quartet states (symmetric A) and a pair of doublet (E) states. We describe here a method for selectively retaining the magnetization of the symmetric states, yielding two and three qubit systems. We create pseudopure states using single-quantum-transition selective pulses and implement two- and three-qubit gates using one- and two-dimensional NMR

    Toward quantum information processing by nuclear magnetic resonance: pseudopure states and logical operations using selective pulses on an oriented spin <SUP>3/2</SUP> nucleus

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    Nuclear magnetic resonance spectroscopy has demonstrated significant experimental progress toward the development of quantum computations. The developments so far have taken place mainly through the use of spin ½ nuclei. In this paper we describe the use of a spin math nucleus, oriented in a liquid crystal matrix for the creation of pseudopure states and the implementation of a complete set of two-qubit reversible logic gates using single-quantum transition-selective pulses, extending the range of practice of NMR toward quantum computation

    PDGF-driven proliferation, migration, and IL8 chemokine secretion in human corneal fibroblasts involve JAK2-STAT3 signaling pathway

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    Purpose: Platelet-derived growth factor (PDGF) is associated with corneal fibroblast migration and proliferation and plays an important role in corneal wound healing. However, the intracellular mechanisms of PDGF-mediated functions in corneal fibroblasts are poorly understood. We tested the hypothesis that PDGF functional activities in the cornea involve the Janus kinase-2/signal transducers and activators of transcription-3 (JAK2-STAT3) signaling pathway and whether PDGF induces the expression of suppressors of cytokine signaling 3 (SOCS3), belonging to the novel family of feedback regulators of cytokine and growth factor activities. Methods: Human corneal fibroblast (HSF) cultures were used as an in vitro model for functional analysis. Real-time polymerase chain reactions were performed to quantify gene expression. Immunoprecipitation and immunoblotting techniques were used to measure protein expression. Cell growth, migration, and ELISA assays were used for functional validation. Results: Low endogenous levels of STAT3 and SOCS3 mRNA and protein expression were noted in HSFs. PDGF treatment of HSF significantly induced SOCS3 mRNA (3.0–4.5 fold) and protein (1.5–2.5 fold) expression in a timedependent manner. Similarly, PDGF treatment of HSF significantly increased STAT3 protein expression at two tested time points (2.5–2.96 fold). Cultures exposed to vehicle (control) did not show any change in SOCS3 and STAT3 mRNA or protein expression. An addition of AG-490, a selective inhibitor of the JAK2-STAT3 pathway, significantly inhibited PDGF-mediated STAT3 induction and cell growth and migration in HSF. We also observed that PDGF induced interleukin-8 (IL8) chemokine secretion (2 fold) and AG-490 inhibited IL8 secretion. Conclusions: Our data showed that PDGF induced STAT3, SOCS3, and IL8 chemokine secretion in human corneal fibroblasts. Further, PDGF-induced cell growth, migration, and IL8 secretion in corneal fibroblast involve the JAK2- STAT3 signaling pathway
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