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1.
Neri Merhav Bhaskaran Vasudev 《Journal of Visual Communication and Image Representation》1996,7(4):395-410
In prior work, we developed a fast inverse motion compensation method that can be implemented directly on the DCT domain representation derived from the compressed bitstreams conforming to MPEG, H.261, and H.263 standards. That work was restricted to compressed-domain representations wherein the motion-vectors have integer pel accuracy. Here, we extend this work to fractional-pel accurate motion-vectors. We also extend the prior work to speed up the inverse motion compensation process in the DCT domain by explicitly exploiting the sparseness of the DCT domain representation. Using partial DCT information, we show that the DCT domain method has substantially lower operation count than the conventional spatial domain approach which requires decompression followed by inverse motion-compensation. 相似文献
2.
B. G. Bhaskaran 《Queueing Systems》1986,1(1):103-127
Given conditions, which concern the infinitesimal parameters of two birth and death processes, the processes are constructed on the same probability space such that one process is almost surely larger than the other. Application is made to M/M/s queueing systems. Stochastic comparisons of queue length and virtual waiting time in two M/M/s systems are obtained. 相似文献
3.
4.
Kulkarni NV Budagumpi S Kurdekar GS Revankar VK Didagi S 《Chemical & pharmaceutical bulletin》2010,58(12):1569-1575
A novel Cu(II) and Zn(II) complexes of triazolo-quinoline derivatives were synthesized by in situ method and were characterized by the spectro-analytical methods and their pharmacological properties were evaluated. The compound C3 has exhibited promising anticonvulsant activity towards the electroshock induced seizures in Wistar rats and possesses low toxicity, providing a high safety profile. 相似文献
5.
H.Y. Tong F.G. Shi B. Zhao S.-Q. Wang M. Brongo P.K. Vasudev 《Applied Physics A: Materials Science & Processing》1997,65(3):287-290
2 multilayers by means of X-ray diffraction, transmission electron microscopy, and an ellipsometer. The FPI precursor, a solution
of PMDA/6FDA/TFMOB/PPD was spin-coated onto the Al layer and then cured at 400 °C for one hour. It is found that the moisture
and oxygen from the FPI layer released during thermal treatment can lead to the oxidation of the interface between the Al
and the FPI. The TEM cross-sectional images and the electron diffraction patterns indicate that the oxidized interface is
amorphous. The oxidation product is identified to be Al2O3. The oxidation onset temperature is determined to be 415 °C, which is slightly higher than the curing temperature. The oxidation
of the FPI/Al interface results in an increase in the electrical resistance of the Al layer, and thus may lead to a reduction
in its effective electrical thickness.
Received: 21 May 1997/Accepted: 27 May 1997 相似文献
6.
M. Sc. Yasemin Akbulut Hannah J. Gaunt Prof. Katsuhiko Muraki Dr. Melanie J. Ludlow Dr. Mohamed S. Amer Dr. Alexander Bruns Dr. Naveen S. Vasudev Dr. Lea Radtke Dr. Matthieu Willot M. Sc. Sven Hahn M. Sc. Tobias Seitz Dr. Slava Ziegler Prof. Dr. Mathias Christmann Prof. Dr. David J. Beech Prof. Dr. Herbert Waldmann 《Angewandte Chemie (International ed. in English)》2015,54(12):3787-3791
Current therapies for common types of cancer such as renal cell cancer are often ineffective and unspecific, and novel pharmacological targets and approaches are in high demand. Here we show the unexpected possibility for the rapid and selective killing of renal cancer cells through activation of calcium‐permeable nonselective transient receptor potential canonical (TRPC) calcium channels by the sesquiterpene (?)‐englerin A. This compound was found to be a highly efficient, fast‐acting, potent, selective, and direct stimulator of TRPC4 and TRPC5 channels. TRPC4/5 activation through a high‐affinity extracellular (?)‐englerin A binding site may open up novel opportunities for drug discovery aimed at renal cancer. 相似文献
7.
Kulsoom Kamal Hardesh K. Maurya Atul Gupta Prema G. Vasudev 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(10):921-928
The revived interest in halogen bonding as a tool in pharmaceutical cocrystals and drug design has indicated that cyano–halogen interactions could play an important role. The crystal structures of four closely related δ‐keto esters, which differ only in the substitution at a single C atom (by H, OMe, Cl and Br), are compared, namely ethyl 2‐cyano‐5‐oxo‐5‐phenyl‐3‐(piperidin‐1‐yl)pent‐2‐enoate, C19H22N2O3, (1), ethyl 2‐cyano‐5‐(4‐methoxyphenyl)‐5‐oxo‐3‐(piperidin‐1‐yl)pent‐2‐enoate, C20H24N2O4, (2), ethyl 5‐(4‐chlorophenyl)‐2‐cyano‐5‐oxo‐3‐(piperidin‐1‐yl)pent‐2‐enoate, C19H21ClN2O3, (3), and the previously published ethyl 5‐(4‐bromophenyl)‐2‐cyano‐5‐oxo‐3‐(piperidin‐1‐yl)pent‐2‐enoate, C19H21BrN2O3, (4) [Maurya, Vasudev & Gupta (2013). RSC Adv. 3 , 12955–12962]. The molecular conformations are very similar, while there are differences in the molecular assemblies. Intermolecular C—H...O hydrogen bonds are found to be the primary interactions in the crystal packing and are present in all four structures. The halogenated derivatives have additional aromatic–aromatic interactions and cyano–halogen interactions, further stabilizing the molecular packing. A database analysis of cyano–halogen interactions using the Cambridge Structural Database [CSD; Groom & Allen (2014). Angew. Chem. Int. Ed. 53 , 662–671] revealed that about 13% of the organic molecular crystals containing both cyano and halogen groups have cyano–halogen interactions in their packing. Three geometric parameters for the C—X...N[triple‐bond]C interaction (X = F, Cl, Br or I), viz. the N...X distance and the C—X...N and C—N...X angles, were analysed. The results indicate that all the short cyano–halogen contacts in the CSD can be classified as halogen bonds, which are directional noncovalent interactions. 相似文献
8.
Madhu Bhaskaran Sharath Sriram Simon Ruffell Arnan Mitchell 《Advanced functional materials》2011,21(12):2251-2257
We report on the use of nanoindentation to characterize in situ the voltage and current generation of piezoelectric thin films. This work presents the controlled observation of nanoscale piezoelectric voltage and current generation, allowing accurate quantification and mapping of force function variations. We characterize both continuous thin films and lithographically patterned nanoislands with constrained interaction area. The influence of size on energy generation parameters is reported, demonstrating that nanoislands can exhibit more effective current generation than continuous films. This quantitative finding suggests that further research into the impact of nanoscale patterning of piezoelectric thin films may yield an improved materials platform for integrated microscale energy scavenging systems. 相似文献
9.
10.
This paper presents experimental results on the application of a new quadrature modulator compensator, which allows existing quadrature modulators to achieve near-ideal RF upconversion over a wide bandwidth. A test setup using an arbitrary waveform generator and a spectrum analyzer shows that over 70 dB of spurious-free dynamic range may be obtained over a bandwidth of 1.2 MHz using an off-the-shelf Mini Circuits in-phase/quadrature modulator operating at 895 MHz. A conventional compensator provides only 45 dB of sideband suppression in the same experimental setup. 相似文献