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排序方式: 共有249条查询结果,搜索用时 0 毫秒
241.
Broad-band wavelength-tunable, single frequency, and single polarization bismuth oxide-based erbium-doped fiber laser 总被引:1,自引:0,他引:1
H. Sotobayashi J.T. Gopinath Y. Takushima K. Hsu E.P. Ippen 《Photonics Technology Letters, IEEE》2004,16(7):1628-1630
We demonstrate a broad-band wavelength-tunable Bismuth Oxide-based Erbium-doped fiber (Bi-EDF) laser covering both the conventional wavelength band and the long wavelength band. It features single frequency and single polarization oscillation; the former is obtained by making the cavity length short and incorporating an intracavity narrow-band fiber Fabry-Pe/spl acute/rot filter, and the latter is achieved with a sigma laser configuration using nonpolarization maintaining fibers. Tuning over 90 nm (1520-1610 nm) is achieved by utilizing the broad gain bandwidth of Bi-EDF amplifier. 相似文献
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It is shown that a coupler and interferometer may be considered two extremes of a generalized two-guide coupler device in which electrode length is less than a coupling length. For electrode lengths less than half of a coupling length, the generalized device looks more like an interferometer than a coupler. The impedance and electrical loss of asymmetric-stripe and coplanar-waveguide transmission lines on LiNbO3 for thick as well as thin electrodes are then presented. The effects of the electrical loss on the bandwidth and drive requirements of traveling-wave LiNbO3 couplers and interferometric devices are discussed, and it is shown that electrical loss in the transmission line is more detrimental to a coupler than to an interferometer. These results are then used to compare the drive power requirements of coupler and interferometric devices, and it is shown that for the same bandwidth and same optical guide dimensions, an interferometric device with a coplanar transmission line can require a lower drive power than a coupler with an asymmetric-stripe line. 相似文献
244.
Gholipour A Kehtarnavaz N Briggs R Devous M Gopinath K 《IEEE transactions on medical imaging》2007,26(4):427-451
Functional localization is a concept which involves the application of a sequence of geometrical and statistical image processing operations in order to define the location of brain activity or to produce functional/parametric maps with respect to the brain structure or anatomy. Considering that functional brain images do not normally convey detailed structural information and, thus, do not present an anatomically specific localization of functional activity, various image registration techniques are introduced in the literature for the purpose of mapping functional activity into an anatomical image or a brain atlas. The problems addressed by these techniques differ depending on the application and the type of analysis, i.e., single-subject versus group analysis. Functional to anatomical brain image registration is the core part of functional localization in most applications and is accompanied by intersubject and subject-to-atlas registration for group analysis studies. Cortical surface registration and automatic brain labeling are some of the other tools towards establishing a fully automatic functional localization procedure. While several previous survey papers have reviewed and classified general-purpose medical image registration techniques, this paper provides an overview of brain functional localization along with a survey and classification of the image registration techniques related to this problem. 相似文献
245.
Standardisation of process parametres for ready-to-eat squid masala in indigenous polymer-coated tin-free steel cans 总被引:1,自引:0,他引:1
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Varghese Anitta Rose Jose Adon Krishnapriya T. George Anns Jose Jeena Rose Gopinath Arya Joseph Cyriac Biju P. R. 《Journal of Materials Science: Materials in Electronics》2022,33(25):20204-20222
Journal of Materials Science: Materials in Electronics - The current study focuses on a comparative investigation of the luminescent properties of fluoroborosilicate glasses doped with the two... 相似文献
248.
Ramesh Sai Jayaraman Kannapan Panchamoorthy Gopinath Jayaseelan Arun Rajagopal Malolan Srikanth Adithya Pattabhiraman Srinivaasan Ajay Ramachandran Sivaramakrishnan Arivalagan Pugazhendhi 《International Journal of Hydrogen Energy》2021,46(31):16555-16564
In this study, wastewater obtained from a sewage treatment plant was treated successively by using microbial consortium and macroalgae Kappaphycus alvarezii to generate microbial sludge and algal biomass. The production of green fuel was carried out via co-gasification of microbial sludge and macroalgae Kappaphycus alvarezii for a duration of 60 min, feedstock to solvent ratio (5 to 20 g of feedstock in 200 mL), sludge to algae ratio (ranging from 1:1 to 3:1) and temperature (300–400 °C) respectively. Maximum bio-hydrogen yield was 36.1% and methane yield was 38.4% at a temperature of 360 °C at a feedstock to solvent ratio of 15:200 g/mL and sludge to algae ratio of 2:1 individually. The liquid by product of co-gasification process was later subjected to photocatalytic reforming, resulted in an enhanced hydrogen composition of 61.25%. 相似文献
249.