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排序方式: 共有893条查询结果,搜索用时 15 毫秒
881.
International Journal of Speech Technology - This article introduces a re-configurable pipeline analog-to-digital converter (ADC) deliberated for implantable surveillance devices for bio-impedance... 相似文献
882.
Clean Technologies and Environmental Policy - Plastics are undebatably a hot topic of discussion across international forums due to their huge ecological footprint. The onset of COVID-19 pandemic... 相似文献
883.
The variable step-size LMS/F algorithm using nonparametric method for adaptive system identification
Ansuman Patnaik Sarita Nanda 《International Journal of Adaptive Control and Signal Processing》2020,34(12):1799-1811
A fundamental challenge affecting the performance of a system is the undesired effect of noise on the system. Practically, real-time systems are influenced by Gaussian noise and impulsive noise. Identification of these nonlinear physical systems in the presence of noise offers broader applications than linear system identification. Hence, this article introduces a variable step-size technique to solve the conflicting requirement of rapid convergence and low mean square error (MSE) in the presence of both Gaussian and impulsive noise. Moreover, to avoid over parameterized equations existing in the variable step-size equation, this article proposes the nonparametric variable step-size (NPVSS), which depends on error estimates at instants of time and is used with the least mean square/fourth (LMS/F) algorithm. The computational complexity analysis, computer simulations, and implementation in real-time setup validate that the proposed NPVSS-LMS/F algorithm provides superior performance in terms of convergence time and MSE compared to the existing algorithms for both linear and nonlinear system identification in the presence of noise. 相似文献
884.
885.
Indira Govindaraju Sparsha Pallen Suchitta Umashankar Sib Sankar Mal Sindhoora Kaniyala Melanthota Dhani Ram Mahato Guan‐Yu Zhuo Krishna Kishore Mahato Nirmal Mazumder 《Microscopy research and technique》2020,83(5):490-498
Starch granules from rice and corn were isolated, and their molecular mechanism on interaction with α‐amylase was characterized through biochemical test, microscopic imaging, and spectroscopic measurements. The micro‐scale structure of starch granules were observed under an optical microscope and their average size was in the range 1–100 μm. The surface topological structures of starch with micro‐holes due to the effect of α‐ amylase were also visualized under scanning electron microscope. The crystallinity was confirmed by X‐ray diffraction patterns as well as second‐harmonic generation microscopy. The change in chemical bonds before and after hydrolysis of the starch granules by α‐ amylase was determined by Fourier transform infrared spectroscopy. Combination of microscopy and spectroscopy techniques relates structural and chemical features that explain starch enzymatic hydrolysis which will provide a valid basis for future studies in food science and insights into the energy transformation dynamics. 相似文献
886.
887.
Kishore Reddy Venkata Thappeta Li Na Zhao Choy Eng Nge Sharon Crasta Chung Yan Leong Veronica Ng Yoganathan Kanagasundaram Hao Fan Siew Bee Ng 《International journal of molecular sciences》2020,21(22)
Sortase A (SrtA) is a membrane-associated enzyme that anchors surface-exposed proteins to the cell wall envelope of Gram-positive bacteria such as Staphylococcus aureus. As SrtA is essential for Gram-positive bacterial pathogenesis but dispensable for microbial growth or viability, SrtA is considered a favorable target for the enhancement of novel anti-infective drugs that aim to interfere with key bacterial virulence mechanisms, such as biofilm formation, without developing drug resistance. Here, we used virtual screening to search an in-house natural compound library and identified two natural compounds, N1287 (Skyrin) and N2576 ((4,5-dichloro-1H-pyrrol-2-yl)-[2,4-dihydroxy-3-(4-methyl-pentyl)-phenyl]-methanone) that inhibited the enzymatic activity of SrtA. These compounds also significantly reduced the growth of S. aureus but possessed moderate mammalian toxicity. Furthermore, S. aureus strains treated with these compounds exhibited reduction in adherence to host fibrinogen, as well as biofilm formation. Hence, these compounds may represent an anti-infective therapy without the side effects of antibiotics. 相似文献
888.
Water dissociation, in general, requires external stimuli such as light energy or electricity. Here, we present a stimuli-free water dissociation using mesoporous SnO2–based hydroelectric cell that can directly be exploited to generate electric power for portable applications. The device configuration is almost identical to metal-air batteries but follows altogether a different reaction pathway. The mesoporous SnO2–based hydroelectric cell dissociates water molecule into hydroxyl ions (OH-) and hydronium ion without any stimuli, transports hydronium ions to the opposite end, and simultaneously acts as the separator. The OH- react with Al electrode to release the electrons, whereas hydronium ions get reduced at the Ag electrode to produce a potential difference as high as ~1000 ± 20 mV between the electrodes that is stable over 3500 hours. The device also shows its potential toward electric power generation from atmospheric moisture with the help of CuO layer that acts as moisture pump. 相似文献
889.
V. R. Pai Verneker K. Kishore B. K. Chaturvedi M. Ramanath 《Propellants, Explosives, Pyrotechnics》1981,6(6):158-160
Ammoniumperchlorate (AP) was aged at 100 °C and 150 °C. Depending on the aging time, AP shows different decomposition characteristics. By a special experimental arrangement sublimation and thermal decomposition could be separated. 相似文献
890.
Thermal decomposition of ammonium perchlorate-polystyrene propellant as a function of oxidizer loading has been found to behave in a fashion analogous to the thermal decomposition of ammonium perchlorate as a function of precompression pressure. It has been argued that the above behaviour of the propellant is due to the strain caused by the binder film on ammonium perchlorate contained in the propellant matrix. The presence of strain has been demonstrated independently by x-ray diffraction peak and infrared peak broadening and strain energy measurements. 相似文献