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31.
A novel plasmonic nanolens formed by a tapered subwavelength metal slit surrounded by surface dielectric gratings is proposed and demonstrated numerically. By patterning surface corrugations on the output surface, the beam can be focused, by regulating the aperture, the focal length can be controlled effectively. Numerical simulations using Finite-Difference Time-Domain (FDTD) method coupled with anisotropic perfectly matched layer (APML) boundary conditions verify that the proposed metallic lens can focus the radiation on the scale of a wavelength below the substrate and the method is effective for the design of nano-optical devices such as optical microprobes. 相似文献
32.
61. IntroductionLet P be a submanifold of an n-dimensional riemannian manifold AI. Expressions fOrthe kth integrated mean curvatures, M^P(t), (i. e. the integral of tho kth mcan curvature,k = 0, 1,' l n -- l), of a tubular hypersurface P of radius t about P, in terms of theRiemann curvature tensor of P. are calculated when AI is Euclidean or a rank one symmetricspace[5'13"1. Moreover, when P is a closed convex hypersurface of thc n-dimensional spaceof constant curvature A', Santal6 has… 相似文献
33.
Kameron Rausch N. Yurt D. F. Geraghty N. Eradat N. Peyghambarian Alan R. Kost 《Optical and Quantum Electronics》2007,39(7):611-622
Broadband arrayed waveguide gratings on InP are presented using a novel S-shape design. This design was utilized to accommodate
the large free spectral range required for broadband operation. Four and eight channel AWGs with a wavelength channel spacing
of 18 nm are discussed. The output peaks of the AWGs have a wide FWHM of 11 nm which provides insensitive operation to polarization,
temperature fluctuations, and chromatic dispersion. 相似文献
34.
In this paper, a new channel drop filter in two dimensional photonic crystals with mirror cavities is proposed. In the structure,
three cavities are used. One is used for a resonant tunneling-based channel drop filter. The others are used to realize reflection
feedback in the bus waveguide, which consists of a point defect micro-cavity side-coupled to a waveguide. The simulation results
by using the finite-difference time-domain method conclude 98% output efficiency. 相似文献
35.
To improve the productivities of an automated container terminal, it is important to schedule different types of handling
equipment in an integrated way. A mixed-integer programming model, which considers various constraints related to the integrated
operations between different types of handling equipment, is formulated. A heuristic algorithm, called multi-layer genetic
algorithm (MLGA) is developed with a view to overcome the computation difficulty for solving the mathematical model. A numerical
experimentation is carried out in order to evaluate the performance of the algorithm. 相似文献
36.
A survey of berth allocation and quay crane scheduling problems in container terminals 总被引:2,自引:0,他引:2
Due to the variety of technical equipments and terminal layouts, research has produced a multitude of optimization models for seaside operations planning in container terminals. To provide a support in modeling problem characteristics and in suggesting applicable algorithms this paper reviews the relevant literature. For this purpose new classification schemes for berth allocation problems and quay crane scheduling problems are developed. Particular focus is put on integrated solution approaches which receive increasing importance for the terminal management. 相似文献
37.
Thomas Simon 《Journal of statistical physics》2008,131(4):733-747
Consider an inviscid Burgers equation whose initial data is a Lévy α-stable process Z with α>1. We show that when Z has positive jumps, the Hausdorff dimension of the set of Lagrangian regular points associated with the equation is strictly
smaller than 1/α, as soon as α is close to 1. This gives a partially negative answer to a Conjecture of Janicki and Woyczynski (J. Stat. Phys. 86(1–2):277–299,
1997). Along the way, we contradict a recent Conjecture of Z. Shi () about the lower tails of integrated stable processes. 相似文献
38.
In this review, we present recent advancements and novel developments in fluidic systems for applied analytical purposes in chemistry, biochemistry, and life science in general that employ and reflect the full benefits of microfluidics. A staggering rise in publications related to integrated, all‐in‐one microfluidic chips capable of separation, reaction, and detection have been observed, all of which realise the principal of micro total analysis systems or lab‐on‐a‐chip. These integrated chips actively adopt the scaling law concepts, utilising the highly developed fabrication techniques. Their aim is to multi‐functionalise and fully automate devices believed to assist the future advancements of point‐of‐care, clinical, and medical diagnostics. 相似文献
39.
A channel drop filter system that consists of two waveguides and three cavities is studied. One cavity couples with both waveguides, while the other two work as resonant mirrors to reflect the selected channel back into the system. The operation of this configuration is analyzed, using coupled mode theory. The conditions to achieve 100% in-plane channel transfer are derived. A method to suppress the side lobes of reflection and backward drop is also proposed. The direct coupling between the cavities is not required. The analysis is verified by two-dimensional finite difference time domain simulations in 2D hexagonal photonic crystals. 相似文献
40.
A numerical study is carried out to compare the two-dimensional (2-D) case and three-dimensional (3-D) case for the modelling of an ion-exchanged glass waveguide. It is shown that different waveguide widths on the photomask correspond to different ion concentration distributions after an annealing process. A numerical example is presented of two waveguide sections with different widths indicates that due to the abrupt change of the waveguide width, a 3-D theoretical model is required for an accurate prediction of the parameters of ion-exchanged glass waveguides. The good agreement between the modelled and measured results proves that the developed 3-D numerical model can be beneficially utilized in the generalized design of optical devices based on ion-exchange waveguides. 相似文献