检索结果-南通市图书馆

维普期刊数据库

Anomalous Positive refraction in an Anisotropic Left-Handed Medium

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2005年第8期22卷 2069-2072页

作者：胡巍罗海陆曹京晓 LaboratoryofLightTransmissionOptics SouthChinaNormalUniversityCuangzhou510631

We investigate the refraction phenomena of extraordinary light at a planar interface associated with a uniaxial left-handed medium. It is found that the anomalous positive refraction can occur at the interface from an isotropic right-handed medium to a uniaxially anisotropic left-handed medium. When the optical axis of a uniaxial left-handed medium is not normal or parallel to the interface, the refraction of the Poynting vector for the extraordinary waves can be either positive or negative depending on the incident angles, while the refraction of the wave vector is always negative. The physical essential of the anomalous positive refraction results from the anisotropy of uniaxial crystals.

关键词： NEGATIVE refraction INDEFINITE MEDIA wave refraction Positive Anomalous Optic axis planar interface refraction Anisotropy

An Analytical Solution for wave Transformation Over Axi-Symmetric Topography

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

China Ocean Engineering 2019年第6期33卷 694-703页

作者： CUONG San Sieu CHANG Jen-Yi TSAI Chia-Cheng CHOU Wan-Rong aInstitute of Oceanography National Taiwan UniversityTaipei 10617China Tainan University of Technology Tainan 71002China Department of Marine Environmental Engineering National Kaohsiung University of Science and TechnologyKaohsiung 81164China Department of Marine Environment and Engineering National Sun Yat-Sen UniversityKaohsiung 80424China Department of Hydraulic and Ocean Engineering National Cheng Kung UniversityTainan 701China

The present study considers wave scattering phenomena around a cylindrical island mounted on a general axisymmetric topography or a general submerged truncated axi-symmetric shoal based on the mild-slope equation. The method of separation of variables and Taylor series expansion are invoked to find the approximate solution to the variable water depth region which varies proportionally to an arbitrary power of radial distance. Validations against the solutions for the combined wave refraction and diffraction around a cylindrical island mounted on a paraboloidal shoal of Liu et al. in 2004 and the scattering and trapping of wave energy by a submerged truncated paraboloidal shoal of Lin and Liu in 2007 show excellent agreements as the power of radial distance being equal to two. For the solutions of wave refraction and diffraction around a cylindrical island mounted on a shoal with depth proportionally to an arbitrary power of radial distance, good agreements with Zhai et al.’s(2013) solutions are demonstrated. Since the robustness of the assumption of a general axi-symmetric geometry based on an arbitrary power variability of the radial distance, the present solution can be very conveniently employed to investigate the effects of bottom topography on wave scattering and trapping patterns.

关键词： general axi-symmetric topography mild-slope equation submerged truncated shoal wave refraction wave diffraction

维普期刊数据库

Near shore waves,long-shore currents and sediment transport along micro-tidal beaches,central west coast of India

在线全文

学校读者我要写书评

暂无评论

International Journal of Sediment Research 2014年第03期29卷 402-413页

作者： Sajiv Philip CHEMPALAYIL V.Sanil KUMAR G.Udhaba DORA Glejin JOHNSON CSIR-National Institute of Oceanagraphy Dona PaulaGoaIndia

Coastlines are undergoing constant geomorphologic changes with respect to the incident wave *** on waves measured at 9 m water depth,simulation of near shore wave transformation is done using REFDIF-1numerical model and the near shore breaker parameters are estimated at two micro-tidal beaches along central west coast of *** results are validated with measured *** the breaker parameters,long-shore current and long-shore sediment transport rates(LSTR) are computed by using semi-empirical *** long-shore current and LSTR are showing dramatic variations with respect to *** direction of LSTR is observed towards north since the approach waves are from south-west direction during pre-monsoon and post *** monsoon season,waves are from west south-west and resulted in southerly *** estimated annual net and gross LSTR by Cambridge Environmental Research Consultants(CERC) at two locations are in the same order whereas LSTR estimated by Walton & Bruno and Kamphuis equations are showing different estimations because of difference in surf-zone width and foreshore slope between the two *** micro-tidal beaches with length less than 6 km,Kamphuis equation is giving agreeable estimation of *** analysis of LSTR estimate shows that coastal inclination is the prominent factor in determining LSTR than incident wave angle.

关键词： Near-shore sedimentation Littoral zone wave refraction wave measurement Coastal zone management Karnataka coast

An Analytic-Numerical Solution of wave Transformation

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

China Ocean Engineering 1995年第1期10卷 43-50页

An analytic-numerical solution of wave transformation in shoaling water is presented in this paper. The analytical expression for wave heights along the wave rays is derived in consideration of the combined effect of water depth shoaling, the wave refraction and the sea bottom friction. The wave rays (orthogonals) are calculated by a fourth order Runge-Kutta algorithm and the wave crest lines are computed by an iteration procedure. The numerical results are compared with analytical solution for a special case of parallel- straight contour shore and field data, and comparisons show that the proposed mathematical model and computation method are very useful and convenient for engineering application.

关键词： wave refraction analytic-numerical solution shoaling water bottom friction

维普期刊数据库