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191.
Gopal B. Avinash 《Scanning》1995,17(3):156-160
To manage large volumes of image data generated routinely using real-time confocal microscopy, compressing image data using a lossy algorithm prior to sustained video rate transferring and/or storing is proposed. Test criteria for determining the acceptability of uncompressed data, both qualitatively and quantitatively, are described, and an empirical demonstration of the use of lossy compression in data management is provided. It is found that, if appropriately used, the lossy compression scheme could retain all the useful information in the data while providing better compression ratios (memory for the original/ memory for the compressed) when compared with a lossless scheme. 相似文献
192.
Experimental behaviour of eccentrically loaded slender circular hollow steel columns in-filled with fibre reinforced concrete 总被引:2,自引:0,他引:2
This paper is based on the experimental study of twelve slender steel tubular columns of circular sections filled with both plain and fibre reinforced concrete. The specimens were tested under eccentric compression to investigate the effects of fibre reinforced concrete on the strength and behaviour of slender composite columns. The slenderness ratio was considered to be the main test parameter. Hollow steel sections of similar specimens were also tested as reference columns. The test results were illustrated by load-deflection and load-strain curves. Various characteristics such as strength, stiffness, ductility, energy absorption capacity and failure mode are discussed. Interpretation of the experimental results indicates that the use of fibre reinforced concrete as infill material has a considerable effect on the strength and behaviour of slender composite columns. 相似文献
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195.
Globally, terrestrial television (TV) broadcasting is in the midst of a complete transition to digital signals. The last analog terrestrial broadcast is expected to be switched off in the early 2020s. This transition presents huge energy savings opportunities that have thus far been ignored. Digital TV switchovers have likely increased energy consumption as countries have completed transitions by providing digital TV converters to analog TV users, which increase energy consumption and extend the life of energy-inefficient analog TVs. We find that if analog TVs were retired at the time of a digital switchover and replaced with super-efficient flat-panel TVs, such as light-emitting diode (LED) backlit liquid crystal display (LCD) TVs, there is a combined electricity savings potential of 32 terawatt hours [TWh] per year in countries that have not yet completed their digital TV transition. In view of these findings as well as the dramatic drops of super-efficient TV prices and the unique early-retirement opportunity resulting from cessation of terrestrial analog broadcasts, TV-exchange programs would easily and substantially advance energy efficiency. 相似文献
196.
Preparation and characterization of barium stannate: application as a liquefied petroleum gas sensor† 总被引:2,自引:0,他引:2
C. V. Gopal reddy S. V. Manorama V. J. Rao 《Journal of Materials Science: Materials in Electronics》2001,12(2):137-142
Barium stannate, BaSnO3, an n-type semiconducting oxide with cubic perovskite structure, has been prepared by the thermal decomposition of barium carbonate (BaCO3) and tin tetrahydroxide (Sn(OH)4). The material was characterized by various physical techniques such as differential thermal analysis (DTA/TG), X-ray diffraction (XRD), BET surface area, Fourier transform infra-red (FT-IR) spectroscopy and scanning electron microscopy (SEM). Of its several applications, this material has proven to be one of the successful candidates for the detection of liquefied petroleum gas (LPG). The sensor has a very good selectivity to detect LPG in comparison to other reducing gases, like carbon monoxide and methane. 相似文献
197.
Divvela Nanda Venkata Gopal Sai Kishore Bhyri R. Gowrishankar 《Photonic Network Communications》2014,28(2):146-153
Next generation of optical networks will witness the advent of flexible spectrum/grid reconfigurable optical add drop multiplexers (ROADMs). The pass band of these next generation ROADMs can be varied depending on the spectral width of the incoming signal. With the pass band becoming a variable, spectrum allocation becomes an added constraint to the currently employed routing and wavelength assignment (RWA) algorithm and hence turns it into a routing, wavelength assignment and spectrum allocation (RWSA) problem. In reality, the future networks will be a mix of “Fixed Spectrum” and “Flexible Spectrum” ROADM nodes. Considering this fact, the paper presents a novel RWSA algorithm. The proposed algorithm is applied on NSFNET and two sample networks—11 nodes, 30 node and the results are presented. 相似文献
198.
C. Vedhi J. Anandha Raj N. Gopal R.M. Somasudaram P. Manisankar 《Synthetic Metals》2010,160(11-12):1307-1312
4, 4′-Diaminodiphenyl sulphone was polymerized (with lithium/cobalt/lithium–cobalt salts) by chemical oxidation method using potassium perdisulphate. The solubility of the chemically prepared polymer–metal nanocomposite was ascertained and it showed good solubility in DMF, chloroform, trichloroethylene and DMSO. The PDDS–Li/Co/Li–Co nanocomposites were characterized by UV–vis and FTIR spectral studies. Amine and imine vibrations observed at 1593 and 1503 cm?1 were shifted to lower wave numbers when the polymer–metal composites were formed. A single absorption peak due to the N–H stretching vibration of the imino groups of polymer–metal nanocomposite is observed around 3459 cm?1 and it suggests the participation of NH group during polymerization. The X-ray diffraction studies revealed the formation of nano sized (82 nm) crystalline polymer. The conductivity of the PDDS–Li–Co nanocomposite was determined to be 6.26 × 10?2 S cm?1. SEM analysis showed mixed granular nature of the polymer–metal nanocomposite. The capacitance (159.04 μF) of chemically synthesized PDDS–Li–Co nanocomposite is suggested as a potential capacitive material. 相似文献
199.
Gopal Dwivedi Toshio Nakamura Sanjay Sampath 《Journal of Thermal Spray Technology》2013,22(8):1337-1347
Real-time curvature measurement of a coating-substrate system during deposition has facilitated the monitoring of coating stresses and provided additional insights into thermal spray deposition mechanisms. However, the non-equilibrium state of coating formation along with harsh spray booth environment introduces complexity not only in data interpretation but also in the coating properties estimation. In this paper, a new procedure is proposed to estimate the elastic modulus of thermal sprayed ceramic coatings using in situ curvature and temperature measurements. In order to correlate the measurable parameters to coating elastic modulus, a systematic study is conducted to develop a suitable methodology. First, various finite element model analyses are carried out to formulate suitable relations between the measurements and elastic modulus. Subsequently, experiments are conducted to validate the procedure to estimate coating moduli. The results are compared with more accurate measurements obtained from post-deposition characterization technique under low temperature thermal cycles. The comparison suggests that the moduli estimated using the proposed procedure are in good agreements with those obtained from the post-deposition technique. Further, the nonlinear response of coatings are evaluated from the estimated moduli during deposition and cool down, which offer additional information on the characteristics of thermal spray coatings. 相似文献
200.
ABSTRACT: Sardine in oil was canned at 3 different Lethality values (F0 5,7, and 9) in retort pouches and aluminum cans in stationary retort. Process time calculations were done mathematically to find out the actual process time. Sardine in oil processed in retort pouches had a lower process time compared with aluminum cans for each F0 value. Instrumental texture analysis was done using a food texture analyzer to study the effect of thermal processing on the texture of thermally processed sardine in oil in aluminum cans and retort pouches. As the F0 value and cook value increased in both the retort pouches and aluminum cans, the textural properties showed a decreasing trend. Hardness of the product canned in both aluminum cans and retort pouches decreased with increase in F0 values. 相似文献