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851.
852.
853.
Francois P.-L. Monerie M. Vassallo C. Durteste Y. Alard F.R. 《Lightwave Technology, Journal of》1989,7(3):500-513
Depending on the spectal width of the source illuminating an interferometer, measurement procedures can utilize either the whole interferogram, or only the fringe envelope, or only the fringe quick oscillations. With an ultraband spectrum source, a simplified adaptation of the methods of Fourier transform spectroscopy yields the variations of the test-fiber propagation constant over the whole wavelength-interval of the source. Chromatic dispersion can then be computed from a single interferogram. With narrower spectrum sources, only the fringe envelopes are utilized and yield measurements of mode delay, with application to chromatic and polarization mode dispersion. In this case, however, interferograms at several wavelengths are necessary. With even narrower spectrum sources, the fringe quick oscillations provide measurements of phase shifts, related to changes in the mode propagation constant, when outside perturbations are applied to the test fiber. A direct method for measuring the third-order nonlinear susceptibilities is discussed. In this case the outside perturbation is an intense pump laser field 相似文献
854.
We report on the Langmuir-Blodgett film deposition and plasma etching of cadmium distearate on n-Gao.47Ino.53As to form a high-barrier-height Schottky barrier. Using this technique to form the gate electrode, we fabricated a 1?m-gate-length inverted InP-GalnAs modulation-doped field-effect transistor (MODFET) with an extrinsic transconductance of 170mS/mm and a cutoff frequencyfT of 19 GHz. 相似文献
855.
856.
CCD型束流截面探测器的主要特点是使用电荷耦合器件做传感器,用束流同步光中的可见光成份做为信号源。该探测器同时具有模拟量和数字量两种输出,工作周期短,速度高,不影响束团粒子寿命,在电子储存环物理运行中,是一种有效的探测设备。 相似文献
857.
H. Nair 《Pattern Recognition and Image Analysis》2006,16(2):234-238
A new graphical tool (Multimedia University’s RSIMANA—Remote-Sensing Image Analyzer) developed for image analysis is described
in this paper. MATLAB and ENVI are some of the commercially available tools in the market that aid in image processing and
analysis. But their current versions are of limited assistance in image analysis; for example, MATLAB can extract the area
of irregular objects and patterns in images, but not their length. ENVI is more focused on image processing than on image
analysis functions. Other commercially available tools are also prohibitively expensive. This indicates the need to develop
a userfriendly graphical tool that meets research objectives in the educational environment.
The text was submitted by the author in English.
Hema Nair. Born 1965. Educational qualifications: B.Tech. (Electrical Engineering) from Government Engineering College affiliated to
University of Calicut, Kerala State, India, 1986; MSc (Electrical Engineering) from National University of Singapore, 1993;
MSc (Computer Science) from Clark Atlanta University, USA, 1996. Previous employment: Researcher and Project Leader in AT
& T, New Jersey, USA, for about 5 years. Also worked in Bangalore, India, before that in Apple Information Technology Ltd.
as Teaching Faculty. Current employment: lecturer, Faculty of Engineering and Technology, Multimedia University, Malaysia.
Current research: the final stages of her PhD in Computer Science at Multimedia University. Scientific interests are image
analysis, pattern recognition, databases, AI, data mining. Member of IEEE (USA) since 1997, Professional Member of ACM (USA)
since 1997, Member of Institution of Engineers (India) since 1986. Reviewer for IASTED International Conference 2004. Current
PhD project entitled “Pattern Extraction and Concept Clustering in Linguistic Terms from Mined Images” is funded by an Intensive
Research in Priority Area (IRPA) grant from Government of Malaysia. Research for MSc in Computer Science from USA was funded
by a research grant from the US Army. Author of three International Conference papers accepted in Portugal, Belgium, and India. 相似文献
858.
A one-dimensional mesoscopic ring with one input and two output leads acts as a spintronic beam splitter. The spatial degree of freedom, i.e., the presence of two different possible output channels, gets intertwined with the spin direction as a consequence of quantum interference and spin-orbit interaction. We investigate this kind of spatial-spin correlation, and show that the output density operator contains no quantum entanglement in the important special case when the device polarizes a perfectly random input spin state. However, the correlations are in general not purely classical, we also present specific input states with maximal spatial-spin entanglement after the ring. 相似文献
859.
860.
R. Breil T. Fries J. Garnaes J. Haycocks D. Hüser J. Joergensen W. Kautek L. Koenders N. Kofod K. R. Koops R. Korntner B. Lindner W. Mirand A. Neubauer J. Peltonen G. B. Picotto M. Pisani H. Rothe M. Sahre M. Stedman G. Wilkening 《Precision Engineering》2002,26(3)
Comparison measurements on reference standards are reported in which 13 partners with different instruments took part. A set of prototype standards which had been produced and calibrated within a European project were used for the measurements. Here, results of measurements on a 240 nm step height standard and a two-dimensional lateral standard with a nominal pitch of 1 μm are reported. 相似文献