In an electromagnetic cloak based on a transformation approach, reduced sets of material properties are generally favored due to their easier implementation in reality, although a seemingly inevitable drawback of undesired reflection exists in such cloaks. Here we suggest using high-order transformations to create smooth moduli at the outer boundary of the cloak, therefore completely eliminating the detrimental scattering within the limit of geometric optics. We apply this scheme to a non-magnetic cylindrical cloak and demonstrate that the scattered field is reduced substantially in a cloak with optimal quadratic transformation as compared to its linear counterpart.
标签: electromagnetic transformation properties approach
上传时间: 2017-03-30
上传用户:pkkkkp
Watermarking schemes evaluation Abstract鈥擠igital watermarking has been presented as a solution to copy protection of multimedia objects and dozens of schemes and algorithms have been proposed. Two main problems seriously darken the future of this technology though. Firstly, the large number of attacks and weaknesses which appear as fast as new algorithms are proposed, emphasizes the limits of this technology and in particu-lar the fact that it may not match users expectations. Secondly, the requirements, tools and methodologies to assess the current technologies are almost non-existent. The lack of benchmarking of current algorithms is bla-tant. This confuses rights holders as well as software and hardware manufacturers and prevents them from using the solution appropriate to their needs. Indeed basing long-lived protection schemes on badly tested watermarking technology does not make sense.
标签: Watermarking watermarking evaluation presented
上传时间: 2013-12-04
上传用户:thinode
This is a code of Pseudo-Arc Length Continuation Method , the method can be used for solving the nonlinear equations, the principle can re found in some text books. In the code,I prove the agreement of the code with other methods
标签: Continuation Pseudo-Arc the solving
上传时间: 2013-12-03
上传用户:xzt
The Hilbert Transform is an important component in communication systems, e.g. for single sideband modulation/demodulation, amplitude and phase detection, etc. It can be formulated as filtering operation which makes it possible to approximate the Hilbert Transform with a digital filter. Due to the non-causal and infinite impulse response of that filter, it is not that easy to get a good approximation with low hardware resource usage. Therefore, different filters with different complexities have been implemented. The detailed discussion can be found in "Digital Hilbert Transformers or FPGA-based Phase-Locked Loops" (http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=4629940). The design is fully pipelined for maximum throughput.
标签: e.g. communication Transform important
上传时间: 2017-06-25
上传用户:gxf2016
This project features a full-hardware sound compressor using the well known algorithm: IMA ADPCM. The core acts as a slave WISHBONE device. The output is perfectly compatible with any sound player with the IMA ADPCM codec (included by default in every Windows). Includes a testbench that takes an uncompressed PCM 16 bits Mono WAV file and outputs an IMA ADPCM compressed WAV file. Compression ratio is fixed for IMA-ADPCM, being 4:1. PLEASE NOTICE THAT THIS CORE IS LICENSED UNDER http://creativecommons.org/licenses/by-nc-sa/3.0/ (Creative Commons Attribution-Noncommercial-Share Alike 3.0 Unported). That means you may use it only for NON-COMMERCIAL purposes.
标签: full-hardware compressor algorithm features
上传时间: 2014-01-14
上传用户:Shaikh
The FPGA can realize a more optimized Digital controller in DC/DC Converters when compare to DSPs. In this paper, based on the FPGA platform, The theoretical analysis, characteristics, simulation and design consideration are given. The methods to implement the digital DC/DC Converters have been researched. The function module, state machine of digital DC/DC controller and high resolution DPWM with Sigma- Delta dither has been introduced. They are verified by experiments on a 20 W, 300 KHz non-isolated synchronous buck converters.
标签: Converters controller optimized Digital
上传时间: 2013-12-31
上传用户:tzl1975
This is a paper describing Pulse Compression technique implemented in the Weather Radar system. This paper presents data examples from the radars and contrasts the use of pulse compression waveforms with more traditional non-modulated pulsed waveforms.
标签: This Compression implemented describing
上传时间: 2017-08-25
上传用户:问题问题
We introduce a sub-cell WENO reconstruction method to evaluate spatial derivatives in the high-order ADER scheme. The basic idea in our reconstruction is to use only r stencils to reconstruct the point-wise values of solutions and spatial derivatives for the 2r-1 th order ADER scheme in one dimension, while in two dimensions, the dimension-by-dimension sub-cell reconstruction approach for spatial derivatives is employed. Compared with the original ADER scheme of Toro and Titarev (2002) [2] that uses the direct derivatives of reconstructed polynomials for solutions to evaluate spatial derivatives, our method not only reduces greatly the computational costs of the ADER scheme on a given mesh, but also avoids possible numerical oscillations near discontinuities, as demonstrated by a number of one- and two-dimensional numerical tests. All these tests show that the 5th-order ADER scheme based on our sub-cell reconstruction method achieves the desired accuracy, and is essentially non-oscillatory and computationally cheaper for problems with discontinuities.
标签: 高精度格式
上传时间: 2016-01-13
上传用户:ccsdcczd
32feet.NET is a shared-source project to make personal area networking technologies such as Bluetooth, Infrared (IrDA) and more, easily accessible from .NET code. Supports desktop, mobile or embedded systems. 32feet.NET is free for commercial or non-commercial use. If you use the binaries you can just use the library as-is, if you make modifications to the source you need to include the 32feet.NET License.txt document and ensure the file headers are not modified/removed. The project currently consists of the following libraries:- Bluetooth IrDA Object Exchange Bluetooth support requires a device with either the Microsoft, Widcomm, BlueSoleil, or Stonestreet One Bluetopia Bluetooth stack. Requires .NET Compact Framework v3.5 or above and Windows CE.NET 4.2 or above, or .NET Framework v3.5 for desktop Windows XP, Vista, 7 and 8. A subset of functionality is available for Windows Phone 8 and Windows Embedded Handheld 8 in the InTheHand.Phone.Bluetooth.dll library.
上传时间: 2016-07-06
上传用户:magister2016
Dynasty 350, 700 208/575 Volt Models W/Auto-Line Maxstar 350, 700 File: TIG (GTAW) Including Optional Cart And Cooler CE And Non-CE Models
上传时间: 2017-03-11
上传用户:zosoong