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51.
Anil Kumar Vuppala K. Sreenivasa Rao Saswat Chakrabarti P. Krishnamoorthy S. R. M. Prasanna 《International Journal of Speech Technology》2011,14(3):259-272
This paper proposes hybrid classification models and preprocessing methods for enhancing the consonant-vowel (CV) recognition
in the presence of background noise. Background Noise is one of the major degradation in real-time environments which strongly
effects the performance of speech recognition system. In this work, combined temporal and spectral processing (TSP) methods
are explored for preprocessing to improve CV recognition performance. Proposed CV recognition method is carried out in two
levels to reduce the similarity among large number of CV classes. In the first level vowel category of CV unit will be recognized,
and in the second level consonant category will be recognized. At each level complementary evidences from hybrid models consisting
of support vector machine (SVM) and hidden Markov models (HMM) are combined for enhancing the recognition performance. Performance
of the proposed CV recognition system is evaluated on Telugu broadcast database for white and vehicle noise. The proposed
preprocessing methods and hybrid classification models have improved the recognition performance compared to existed methods. 相似文献
52.
Ashmika Foolchand Siyanda Mazaleni Terisha Ghazi Anil A. Chuturgoon 《International journal of molecular sciences》2022,23(20)
The highly transmittable and infectious COVID-19 remains a major threat worldwide, with the elderly and comorbid individuals being the most vulnerable. While vaccines are currently available, therapeutic drugs will help ease the viral outbreak and prevent serious health outcomes. Epigenetic modifications regulate gene expression through changes in chromatin structure and have been linked to viral pathophysiology. Since epigenetic modifications contribute to the life cycle of the virus and host immune responses to infection, epigenetic drugs are promising treatment targets to ameliorate COVID-19. Deficiency of the multifunctional secosteroid hormone vitamin D is a global health threat. Vitamin D and its receptor function to regulate genes involved in immunity, apoptosis, proliferation, differentiation, and inflammation. Amassed evidence also indicates the biological relations of vitamin D with reduced disease risk, while its receptor can be modulated by epigenetic mechanisms. The immunomodulatory effects of vitamin D suggest a role for vitamin D as a COVID-19 therapeutic agent. Therefore, this review highlights the epigenetic effects on COVID-19 and vitamin D while also proposing a role for vitamin D in COVID-19 infections. 相似文献
53.
Ground rubber tire (GRT) powder was maleated in an internal mixer using maleic anhydride and dicumyl peroxide at 160°C. Maleated GRT was characterized by using X‐ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, wettability, and differential scanning calorimetry. The physical properties of the dynamically vulcanized 60 : 40, rubber : plastic composition based on acrylated high‐density polyethylene as the plastic phase and ethylene propylene diene rubber containing maleated GRT as the rubber phase were found to be greater than the corresponding composition containing nonmaleated GRT. The blend was found to be reprocessable, like themoplastic elastomers. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 370–378, 2002; DOI 10.1002/app.10348 相似文献
54.
Manzer H. Siddiqui Mutahhar Y. Al-Khaishany Mohammed A. Al-Qutami Mohamed H. Al-Whaibi Anil Grover Hayssam M. Ali Mona S. Al-Wahibi Najat A. Bukhari 《International journal of molecular sciences》2015,16(5):10214-10227
Drought stress is one of the major abiotic stresses that are a threat to crop production worldwide. Drought stress impairs the plants growth and yield. Therefore, the aim of the present experiment was to select the tolerant genotype/s on the basis of moprpho-physiological and biochemical characteristics of 10 Vicia faba genotypes (Zafar 1, Zafar 2, Shebam, Makamora, Espan, Giza Blanka, Giza 3, C4, C5 and G853) under drought stress. We studied the effect of different levels of drought stress i.e., (i) normal irrigation (ii) mild stress (iii) moderate stress, and (iv) severe stress on plant height (PH) plant−1, fresh weight (FW) and dry weight (DW) plant−1, area leaf−1, leaf relative water content (RWC), proline (Pro) content, total chlorophyll (Total Chl) content, electrolyte leakage (EL), malondialdehyde (MDA), hydrogen peroxide (H2O2) content, and activities of catalase (CAT), peroxidase (POD) and superoxide dismutase (SOD) of genotypes of faba bean. Drought stress reduced all growth parameters and Total Chl content of all genotypes. However, the deteriorating effect of drought stress on the growth performance of genotypes “C5” and “Zafar 1” were relatively low due to its better antioxidant enzymes activities (CAT, POD and SOD), and accumulation of Pro and Total Chl, and leaf RWC. In the study, genotype “C5” and “Zafar 1” were found to be relatively tolerant to drought stress and genotypes “G853” and “C4” were sensitive to drought stress. 相似文献
55.
Pinka Chakraborty Anirban Ganguly Suman Mitra Anil K. Bhowmick 《Polymer Engineering and Science》2008,48(3):477-489
A series of thermoplastic elastomers (TPEs) were prepared from a binary blend of ethylene propylene diene rubber (EPDM) and isotactic polypropylene (iPP) using different types of phase modifiers. The influence of sulphonated EPDM, maleated EPDM, styrene‐ethylene‐co‐butylene‐styrene block copolymer, maleated PP, and acrylated PP as phase modifiers showed improved physico‐mechanical properties (like maximum stress, elongation at break, moduli, and tension set). Scanning electron and atomic force microscopy studies revealed better morphologies obtained with these phase modified EPDM‐iPP blends. The dependence of the phase modifier type and concentration was optimized with respect to the improvement in physical properties and morphology of the blends. Physical properties, dynamic mechanical properties, and morphology of these blends were explained with the help of interaction parameter, melt viscosity, and crystallinity of the blends. Theoretical modeling showed that Kerner, Ishai‐Cohen, and Paul models predicted the right morphology–property correlation for the prepared TPEs. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers. 相似文献
56.
Røtterud OJ Helps CR Hillman TJ Fisher AV Harbour D Anil H Nesbakken T 《Journal of food protection》2006,69(2):405-411
Compared with traditional boning of split refrigerated carcasses, hot boning of intact carcasses (the removal of meat from the skeleton prerigor) provides several commercially important cuts, may improve quality and reduce refrigeration costs, and may reduce the contamination of carcasses with central nervous system (CNS) tissue. In a comparative study of hot boning of intact and split carcasses, the CNS tissue contamination of intact carcasses was negligible (as measured with the CNS-related proteins glial fibrillary acidic protein and S-100 protein), but split carcasses were highly contaminated. The same trends were observed for dissection worktables used during the boning process. Most current boning plants have processing lines that are organized for boning carcass quarters, where the carcasses, in addition to transversal division, also are split horizontally. This part of the boning process was incorporated in the design of our study. Nine of the 18 intact carcasses were split horizontally between thoracic vertebrae 10 and 11 before they were hot boned. CNS tissue contamination was not detected on the carcass site related to this procedure. The amount of CNS tissue contamination was similar in boned cuts and minced meat from split and intact carcasses, except in the forerib. Boning of split carcasses appears to reduce CNS tissue contamination significantly to a level comparable to that of intact hot-boned carcasses. 相似文献
57.
Monoj Pramanik Suneel Kumar Srivastava Biswas Kumar Samantaray Anil Kumar Bhowmick 《应用聚合物科学杂志》2003,87(14):2216-2220
Ethylene vinyl acetate rubber (45% vinyl acetate content, EVA‐45) and organomodified clay (12Me‐MMT) composites were prepared by solution blending of the rubber and the clay. A combination of X‐ray diffraction, scanning electron microscopy, and transmission electron microscopy studies showed that the composites obtained are on the nanometer scale. The measurements of the dynamic mechanical properties for different compositions over a temperature range (?100 to +100°C) showed that the storage moduli of these rubber–clay nanocomposites are higher above the glass to rubber transition temperature compared to the neat rubber. The tensile strength of the nanocomposites is about 1.6 times higher than that of the EVA‐45. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 87: 2216–2220, 2003 相似文献
58.
Electric vehicles (EVs) are becoming increasingly popular because of their low operating costs. However, the anticipated increase in EV usage presents opportunities as well as challenges for utilities. This paper models EV charging behavior of active consumers who strategize their EV charging schedule to minimize the charging cost. The electric utility employs a temporal and spatially varying real-time pricing scheme that minimizes peak-to-average load ratio by influencing charging behavior of multiple active consumers. These active consumers decide their optimal charging strategy based on real-time electricity prices in order to minimize their EV charging cost. A model predictive control (MPC)-based optimal pricing scheme for electric utility and optimal charging strategy for active consumers is proposed. Effects of the proposed approach on load profile is verified using simulations. 相似文献
59.
Rubber‐based nanocomposites were prepared with octadecyl amine modified sodium montmorillonite clay and styrene–butadiene rubber with different styrene contents (15, 23, and 40%). The solvent used to prepare the nanocomposites, the cure conditions, and the cure system were also varied to determine their effect on the properties of the nanocomposites. All the composites were characterized with X‐ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and transmission electron microscopy (TEM). The XRD studies revealed exfoliation for the modified clay–rubber composites. The TEM photomicrographs showed a uniform distribution of the modified clay in the rubber matrix. The thickness of the particles in the exfoliated composites was around 10–15 nm. Although the FTIR study of the unmodified and modified clays showed extra peaks due to the intercalation of the amine chains into the gallery, the spectra for the rubber–clay nanocomposites were almost the same because of the presence of a very small amount of clay in the rubber matrix. All the modified clay–rubber nanocomposites displayed improved mechanical strength. The styrene content of the rubber had a pronounced effect on the properties of the nanocomposites. With increasing styrene content, the improvement in the properties was greater. Dicumyl peroxide and sulfur cure systems displayed similar strength, but higher elongation and slightly lower modulus values were obtained with the sulfur cure system. The curing of the samples at four different durations at 160°C showed that the cure time affected the properties. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 698–709, 2004 相似文献
60.
Different rubber formulations were designed using nitrile rubber and a mixed crosslinking system consisting of sulfur/accelerator and electron beam radiation. Based on the experimental results, an artificial neural network (ANN) was constructed to simulate the mechanical properties and volume fraction of rubber. The ANN could predict accurately the above properties for a series of nitrile rubber compounds. However, the number of training data played a key role in the ANN predictive quality. In addition, the more complex the nonlinear relation between input and output was, the larger was the number of training dataset required. The predicted results were further validated using another mathematical model. The constructed ANN was verified with a completely different styrene butadiene rubber system. The prediction was found to be extremely good. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 2227–2237, 2006 相似文献