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101.
Sub Hur Hodeok Jang Yonghoon Kim Hanlim Lee Seongtaek Hwang Yunje Oh Y. J. Sung Y. S. Kim Jichai Jeong 《Optical and Quantum Electronics》2007,39(7):561-569
We investigate the performance limits of a pico-cell system using the radio- over-fiber technique with an electroabsorption
modulator (EAM) in a 2.4 GHz wireless local area network (WLAN) environment. To understand the performance limits of the system
using an EAM as the optical transceiver, we vary the optical modulation index (OMI) of the transmitter for different bias
voltages to the EAM. Power margins in the links are found to estimate a possible service range, and packet loss rates (PLRs)
in the pico-cell system are measured to evaluate the transmission performance. The total service range can be extended up
to 3 m by adjusting the OMI of the transmitter for different applied bias voltages to the EAM. 相似文献
102.
103.
S. M. Abdur Razzak Yoshinori Namihira Kazuya Miyagi Feroza Begum Shubi Kaijage Nguyen Hoang Hai Tatsuya Kinjo Nianyu Zou 《Optical Review》2007,14(1):14-16
This paper presents a novel technique for the control of chromatic dispersion and confinement loss in hexagonal photonic crystal
fibers (H-PCFs). It is demonstrated that it is possible to obtain very low chromatic dispersion of 0 ± 0:38 ps/(nm·km) in
the wavelength range of 1.41 to 1.66 μm and confinement loss of less than 0.0001 dB/km from a six ring modified H-PCF (MH-PCF).
The higher order dispersion at 1.55 μm is about −0.001 ps/(nm2-km). 相似文献
104.
Using results for the distribution of perimeters of random polygons arising from random lines in a plane, we obtain new analytic
approximations to the distributions of areas and local line densities for random polygons and compute various limiting properties
of random polygons. Using simulation, we show that the lengths of adjacent sides of polygons generated by random line processes
in the plane are correlated with ρ=0.616±0.001. 相似文献
105.
M. N. Huxley 《Proceedings Mathematical Sciences》1987,97(1-3):111-116
The area of a simple closed convex curve can be estimated in terms of the number of points of a square lattice that lie within
the curve. We obtain the usual error bound without integration using a form of the Hardy—Littlewood—Ramanujan circle method,
and also present simple estimates for the mean square error. 相似文献
106.
2006年,Schuster提出了径向Blaschke-Minkowski同态的概念.随后,汪卫等人将其推广到Lp径向Blaschke-Minkowski同态.本文结合Lp对偶几何表面积,建立了Lp径向Blaschke-Minkowski同态的若干不等式,包括Brunn-Minkowski型不等式和单调不等式.并给出了Lp径向Blaschke-Minkowski同态的Busemann-Petty问题的肯定和否定形式. 相似文献
107.
The specific interfacial area (S/V) and interfacial thickness in each microstructure of styrene-isoprene diblock copolymer were estimated by analyzing the deviations from Porod’s law. The thermally induced phase transitions proceeded from lamellae (L) to hexagonally ordered cylinder (HEX), via hexagonally perforated layer (HPL) and gyroid (G). The S/V ratio increased stepwise at the order-order transition (OOT) from L to HEX, via HPL and G. The S/V data can be utilized for OOT determination. 相似文献
108.
In this paper, we study a second order variational problem for locally convex hypersurfaces, which is the affine invariant analogue of the classical Plateau problem for minimal surfaces. We prove existence, regularity and uniqueness results for hypersurfaces maximizing affine area under appropriate boundary conditions.
109.
Maria F. Ebel Horst Ebel Guido Barnegg-Golwig Michael Mantler Robert Svagera 《Mikrochimica acta》1990,101(1-6):63-69
The paper gives an outline of the basic principle of our imaging technique for XPS. The advantage of the concept is its excellent applicability to quantitative pixel information. This idea is verified by two examples which are representative for routine problems in XPS. These are quantitative surface analysis and determination of overlayer thicknesses. A lateral resolution of at least 0.2 mm is achieved and thus a pixel size of 0.2 mm × 0.2 mm can be quantified automatically by means of numerical algorithms without need of reference samples.Dedicated to Professor Günther Tölg on the occasion of his 60th birthday 相似文献
110.
Recently, a 4-node quadrilateral membrane element AGQ6-I, has been successfully developed for analysis of linear plane problems. Since this model is formulated by the quadrilateral area coordinate method (QACM), a new natural coordinate system for developing quadrilateral finite element models, it is much less sensitive to mesh distortion than other 4-node isoparametric elements and free of various locking problems that arise from irregular mesh geometries. In order to extend these advantages of QACM to nonlinear applications, the total Lagrangian (TL) formulations of element AGQ6-I was established in this paper, which is also the first time that a plane QACM element being applied in the implicit geometrically nonlinear analysis. Numerical examples of geometrically nonlinear analysis show that the presented formulations can prevent loss of accuracy in severely distorted meshes, and therefore, are superior to those of other 4-node isoparametric elements. The efficiency of QACM for developing simple, effective and reliable serendipity plane membrane elements in geometrically nonlinear analysis is demonstrated clearly. 相似文献