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61.
This paper discusses the significance of segmental and prosodic knowledge sources for developing a text-to-speech system for
Indian languages. Acoustic parameters such as linear prediction coefficients, formants, pitch and gain are prestored for the
basic speech sound units corresponding to the orthographic characters of Hindi. The parameters are concatenated based on the
input text. These parameters are modified by stored knowledge sources corresponding to coarticulation, duration and intonation.
The coarticulation rules specify the pattern of joining the basic units. The duration rules modify the inherent duration of
the basic units based on the linguistic context in which the units occur. The intonation rules specify the overall pitch contour
for the utterance (declination or rising contour), fall-rise patterns, resetting phenomena and inherent fundamental frequency
of vowels. Appropriate pauses between syntactic units are specified to enhance intelligibility and naturalness. 相似文献
62.
Muthuvelu Kirupa Sankar Ethiraj Baranitharan Pramnik Shreyasi Raj N. Keerthish Venkataraman Swethaa Rajendran Devi Sri Bharathi Priyadharshini Palanisamy Elakiya Narayanan Anusri Sathiya Vaidyanathan Vinoth Kumar Muthusamy Shanmugaprakash 《Food science and biotechnology》2023,32(10):1337-1350
Food Science and Biotechnology - Despite centuries of developing strategies to prevent food-associated illnesses, food safety remains a significant concern, even with multiple technological... 相似文献
63.
Mohammad Bani Ismail Peramaiyan Rajendran Hamad Mohammed AbuZahra Vishnu Priya Veeraraghavan 《International journal of molecular sciences》2021,22(8)
Doxorubicin increases endothelial permeability, hence increasing cardiomyocytes’ exposure to doxorubicin (DOX) and exposing myocytes to more immediate damage. Reactive oxygen species are major effector molecules of doxorubicin’s activity. Mangiferin (MGN) is a xanthone derivative that consists of C-glucosylxanthone with additional antioxidant properties. This particular study assessed the effects of MGN on DOX-induced cytotoxicity in human umbilical vein endothelial cells’ (HUVECs’) signaling networks. Mechanistically, MGN dramatically elevated Nrf2 expression at both the messenger RNA and protein levels through the upregulation of the PI3K/AKT pathway, leading to an increase in Nrf2-downstream genes. Cell apoptosis was assessed with a caspase-3 activity assay, transferase-mediated dUTP-fluorescein nick end labeling (TUNEL) staining was performed to assess DNA fragmentation, and protein expression was determined by Western blot analysis. DOX markedly increased the generation of reactive oxygen species, PARP, caspase-3, and TUNEL-positive cell numbers, but reduced the expression of Bcl-2 and antioxidants’ intracellular concentrations. These were effectively antagonized with MGN (20 μM), which led to HUVECs being protected against DOX-induced apoptosis, partly through the PI3K/AKT-mediated NRF2/HO-1 signaling pathway, which could theoretically protect the vessels from severe DOX toxicity. 相似文献
64.
65.
Effect of surface modification of anode with surfactant on the performance of microbial fuel cell 下载免费PDF全文
Young‐Chae Song Dae‐Sup Kim Jung‐Hui Woo Bakthavachallam Subha Seong‐Ho Jang Subpiramaniyam Sivakumar 《国际能源研究杂志》2015,39(6):860-868
Surface modification of anode using surfactant has great influence on the electrical performance of a microbial fuel cell (MFC). In this study, the effect of surface‐modified exfoliated graphite used for anode fabrication on a cube‐type MFC batch reactor was examined. The surface exfoliated graphite was modified with 5‐mM anionic surfactant, sodium dodecyl sulfate. Anaerobic sludge used as inoculum containing 70% (v/v) of artificial wastewater and 30% (v/v) of seed sludge in an anode chamber and air cathode was used in cathode side. Anode modification was explored as an approach to enhance the start‐up and improve the performance of the reactor. Scanning electron microscopy was used to evaluate the morphology and activity of electrochemically active bacteria. In the study, the start‐up time of MFC required to approach stable voltage was substantially reduced, and the maximum stable voltage was higher than the control. In addition, the activation resistance of the MFC was considerably reduced, and the maximum power density (1640 mW/m2) was 20% higher than control. However, when the surface of exfoliated graphite was modified with over 10‐mM anionic surfactant, some negative effects on start‐up time, activation resistance and maximum power density were observed. This modification also enhanced the bacterial attachment and biofilm formation on the modified anode surface. The result suggested that surface modification anode with surfactant is effective for electrical responses achieved in the MFC. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
66.
Sensitivity-based conceptual design and tolerance allocation using the continuous ants colony algorithm (CACO) 总被引:1,自引:2,他引:1
G. Prabhaharan P. Asokan S. Rajendran 《The International Journal of Advanced Manufacturing Technology》2005,25(5-6):516-526
In an assembly, there are two ways to control the deviation of critical dimensions. One is by keeping the deviation of the critical dimension small by tightening manufacturing tolerances and controlling aging and environmental effects. This approach is traditional and expensive, as it requires tighter manufacturing tolerances and protection from aging and the environment. The second is by moving the nominal values of the non-critical dimensions to a less sensitive portion. This approach is very helpful in improving the quality with no additional cost. One can analyze any number of designs very early in the concept development stage of a project. After the concept design the cost-based optimal tolerances for the corresponding dimensions are allocated. The continuous ants colony algorithm, a kind of meta-heuristic approach, is used as an optimization tool for minimizing the critical dimension deviation and allocating the cost- based optimal tolerances. 相似文献
67.
Wireless Networks - The rapid escalation of user traffic and service innovation has made the deployment of small cell base stations essential for eventually decreasing energy consumption in future... 相似文献
68.
Sung Chul Kim Rajendran Prabakaran D. Sakthivadivel N. Thangapandian Arpit Bhatia 《Fullerenes, Nanotubes and Carbon Nanostructures》2020,28(11):925-933
AbstractIn this study, stability, density, rheology, and thermal conductivity of the Multi-wall carbon nanotubes (MWCNTs) based PCM nanocomposites were experimentally investigated. The PCM OM08 has been selected for the air-conditioning application with a phase change temperature of 8–10?°C. PCM nanocomposites (without surfactant) in various concentrations namely 0.05, 0.1, 0.3 and 0.5?vol. % were prepared using a typical two-step method and high homogenous stability is achieved using a mechanical mixing technique (ultra-sonication). The density of PCM nanocomposites was measured using two different types of standard volumetric flask approach and the experimental values confirmed good conformity with the Pak and Cho mixing theory. The highest thermal conductivity augmentation of 24.03%and 64.04% were achieved in liquid and solid states, respectively, with 0.5?vol. % of MWCNT. While, the addition of MWCNT resulted in a changeover of Newtonian to Non-Newtonian behaviors at a low shear rate, and the dynamic viscosity enhancement was increased by 130% with 0.5?vol. % of MWCNT. Further, the results were compared with existing correlations and it was found that the experimental values were in line with existing correlations. 相似文献
69.
Arumugham Sukanya Rajendran Rajeswari Kamatchigounder Subramaniam Murugan 《International journal of imaging systems and technology》2020,30(3):716-730
Recent research suggests that the cardiovascular diseases (CVDs), seem to be the foremost cause of mortality among the world populace. Three dimensional (3D) imaging modality such as computed tomography angiography(CTA) is a standard noninvasive imaging modality which has great potentials for the visualization of heart and coronary arteries. This article presents a fully automated method for coronary artery extraction using modified Frangi's vesselness measure and region based segmentation. In this article, grayness and gradient based measures are used while computing Frangi's vesselness measure to improve the extraction of coronary arteries. The obtained vesselness measures are utilized for automatically computing the location of ostia. The locations of ostia are then used as starting seed points in region growing segmentation to extract coronary arteries. Three major coronary arteries, namely the left anterior descending artery (LAD), left circumflex artery (LCX) and right coronary artery (RCA) are segmented using the proposed method and the centerlines are extracted for the main coronary branches. The performance of the proposed method is evaluated using 12 3D CCTA data set. The experimental results reveal that during the calculation of modified Frangi's vesselness measure the proposed method gives improved results. The qualitative results obtained during the segmentation stage are also convincing. The average segmentation accuracy and overlap measure of the proposed method are 97.4% and 77.86%, respectively. Hence, the proposed automated approach can detect and extract coronary arteries in CCTA images with high performance. 相似文献
70.
Narayanan Guru Nisha Ananthasubramanian Pavithra Rajendran Ajay Rakkesh Annamalai Karthigeyan Subramanian Balakumar Veluswamy Pandiyarasan Ikeda Hiroya 《Journal of Materials Science: Materials in Electronics》2022,33(12):9455-9470
Journal of Materials Science: Materials in Electronics - In this work, hydrogen-sensing characteristics of zinc oxide nanorods and reduced graphene oxide-incorporated zinc oxide nanorods are... 相似文献