We obtained the energy transport velocity distribution for a three dimensional ideal cloak explicitly. Near the operation frequency, the energy transport velocity has rather peculiar distribution. The velocity along a line joining the origin of the cloak is a constant, while the velocity approaches zero at the inner boundary of the cloak. A ray pointing right into the origin of the cloak will experience abrupt changes of velocities when it impinges on the inner surface of the cloak. This peculiar distribution causes long time delays for beams passing through the ideal cloak within a geometric optics description.
标签： distribution dimensional transport obtained
上传时间： 2013-12-19
上传用户：zhliu007
This program incorporates the FV method for solving the Navier-Stokes equations using 2D, Cartesian grids and the staggered arrangement of variables. Variables are stored as 2D arrays. SIMPLE method is used for pressure calculation. UDS and CDS are implemented for the discretization of convective terms, CDS is used for the diffusive terms. The boundary conditions are set for the lid-driven cavity flow. Only steady flows are considered.
标签： Navier-Stokes incorporates Cartesian equations
上传时间： 2017-05-14
上传用户：ryb
The 2D CFD Program NaSt2D The program is a 2D solver for the incompressible, transient Navier-Stokes equations including the temperature equation and free boundary problems. It uses finite differences for discretization on a structured equidistant staggered grid, central and upwind (donor-cell) discretization of the convective parts and an explicit time stepping scheme. The free boundary value problems are treated with the MAC technique.
标签： incompressible Navier-Sto The transient
上传时间： 2013-11-30
上传用户：xfbs821
Solves the incompressible Navier-Stokes equations in a rectangular domain with prescribed velocities along the boundary. The standard setup solves a lid driven cavity problem.
标签： incompressible Navier-Stokes rectangular prescribed
上传时间： 2013-11-25
上传用户：15736969615
迷宫算法（maze） /* Maze * Starting point is m[0][0], need to find a path go to m[9][9]. 0 means OK, * 1 means cannot go there, boundary is 0 and 9, cannot go beyond boundary. * Each step can be made horizontally or vertically for one more grid (diagonal * jump is not allowed). * Your program should print a series of grid coordinates that start from m[0][0] * and go to m[9][9] * Hint: No need to find the shortest path, only need to find one path that gets * you to desitination. */
上传时间： 2013-12-27
上传用户：Divine
matlab有限元网格划分程序 DistMesh is a simple MATLAB code for generation of unstructured triangular and tetrahedral meshes. It was developed by Per-Olof Persson (now at UC Berkeley) and Gilbert Strang in the Department of Mathematics at MIT. A detailed description of the program is provided in our SIAM Review paper, see documentation below. One reason that the code is short and simple is that the geometries are specified by Signed Distance Functions. These give the shortest distance from any point in space to the boundary of the domain. The sign is negative inside the region and positive outside. A simple example is the unit circle in 2-D, which has the distance function d=r-1, where r is the distance from the origin. For more complicated geometries the distance function can be computed by interpolation between values on a grid, a common representation for level set methods. For the actual mesh generation, DistMesh uses the Delaunay triangulation routine in MATLAB and tries to optimize the node locations by a force-based smoothing procedure. The topology is regularly updated by Delaunay. The boundary points are only allowed to move tangentially to the boundary by projections using the distance function. This iterative procedure typically results in very well-shaped meshes. Our aim with this code is simplicity, so that everyone can understand the code and modify it according to their needs. The code is not entirely robust (that is, it might not terminate and return a well-shaped mesh), and it is relatively slow. However, our current research shows that these issues can be resolved in an optimized C++ code, and we believe our simple MATLAB code is important for demonstration of the underlying principles. To use the code, simply download it from below and run it from MATLAB. For a quick demonstration, type "meshdemo2d" or "meshdemond". For more details see the documentation.
标签： matlab有限元网格划分程序
上传时间： 2015-08-12
上传用户：凛风拂衣袖
Received: from mail.creditcard.cmbc.com.cn (unknown [111.205.122.39]) by newmx82.qq.com (NewMx) with SMTP id for <714620454@QQ.COM>; Fri, 20 Oct 2017 03:56:09 +0800 X-QQ-FEAT: nHaaMjwLeTyzuDp5C5V++RVfPHSVEqOujK0vwZroSro= X-QQ-MAILINFO: MjJD59SVx+LnQ1oU2sDuZ8tZJyZAOGTJaybWFAYRjurknrZoc6gjmnU06 o+pkiTJsdtxgA5CmtpN2ggrWb/T2GoG07QFXqgJtIk+5X1iaz4UykQ9M2a782+Fdn83doxC 4Ej1t99JoZcj8dDkeM5dzZTSR8uZGwHEnIK9Uim+NcaroB2EUWgclSmSzIxUHIbJ1nTLA8G B4/wa X-QQ-mid: mx82t1508442969ti70kc84u X-QQ-ORGSender: master@creditcard.cmbc.com.cn Received: from sedm([195.203.59.13]) by mail.creditcard.cmbc.com.cn(1.0) with SMTP id sedm587; Thu, 19 Oct 2017 17:48:11 +0800 Date:Thu, 19 Oct 2017 17:48:11 +0800 (CST) Message-ID:<0305-euid-31911508406491578> To:=?gbk?B?zsTS1SDFrsq/?=<714620454@QQ.COM> From:master<master@creditcard.cmbc.com.cn> Subject: =?gbk?B?w/HJ+tDF08O/qDIwMTfE6jEw1MK159fTttTVy7Wl?= X-Priority: 3 X-MSMail-Priority: Normal MIME-Version: 1.0 Content-Type: multipart/related; boundary="****MAIN_boundary****2727BD00F7949069C75FEDD44F1F2988" This is a multi-part message in MIME format. --****MAIN_boundary****2727BD00F7949069C75FEDD44F1F2988 Content-Type: multipart/alternative; boundary="****SUB_boundary****2727BD00F7949069C75FEDD44F1F2988" --****SUB_boundary****2727BD00F7949069C75FEDD44F1F2988 Content-Type: text/html; charset="gb2312" Content-Transfer-Encoding: base64
标签： 源代码
上传时间： 2017-11-17
上传用户：wendingchang
可测试性设计（Design-For-Testability，DFT）已经成为芯片设计中不可或缺的重要组成部分。它通过在芯片的逻辑设计中加入测试逻辑提高芯片的可测试性。在高性能通用 CPU 的设计中，可测试性设计技术得到了广泛的应用。本文结合几款流行的 CPU，综述了可应用于通用 CPU 等高性能芯片设计中的各种可测试性方法，包括扫描设计（Scan Design），内建自测试（Built-In Self-Test，BIST），测试点插入（Test Point Insertion），与 IEEE 1149.1标准兼容的边界扫描设计（boundary Scan Design，BSD）等技术。
上传时间： 2021-10-15
上传用户：
ABSTRACTThe flyback power stage is a popular choice for single and multiple output dc-to-dc converters at powerlevels of 150 Watts or less. Without the output inductor required in buck derived topologies, such as theforward or push-pull converter, the component count and cost are reduced. This application note will reviewthe design procedure for the power stage and control electronics of a flyback converter. In these isolatedconverters, the error signal from the secondary still needs to cross the isolation boundary to achieveregulation. By using the UC3965 Precision Reference with Low Offset Error Amplifier on the secondaryside to drive an optocoupler and the UCC3809 Economy Primary Side Controller on the primary side, asimple and low cost 50 Watt isolated power supply is realized.
标签： 隔离
上传时间： 2021-11-24
上传用户：kingwide
结构体的具体尺寸如下所示：a=1.20h=0.620其中介质锥的介电常数E=2.0。选定工作频率为f=15GHz相对应的真空中的波长为0=20mm，这样结构体的儿何尺寸己经完全确定，下面介绍求解的全过程选定求解方式为（Solution Type）Driven modal1.建立所求结构体的几何模型（单位：mm）。由于此结构体的几何形状较简单，使用工具栏中的Draw命令可直接画出，这里不再赘述述。画出的结构体如图4.1.2所示。2.充结构体的材料选定结构体中的锥体部分，添加其介电常数Er=20的介质材料注：如果HSS中没有提供与所需参数完全相同的材料，用户可以通过新建材料或修改已有材料，使其参数满足用户需求设定结构体的边界条件及其激励源a.选定结构体的贴片部分，设定其为理想导体（PerE）。b.画出尺寸为X×Y×Z=70mm×70mm×40mm的长方体作为辐射边界，并设定其边界条件为辐射边界条件（Radiation boundary）。c.由于要求出结构体的RCS，因此设定激励源为平面入射波（Incident Wave Source）。如图4.1.3所示。4.设定求解细节，检验并求解a.设定求解过程的工作频率为f=15GHz.其余细节设定如图4.1.4所示。b.设定远区辐射场的求解（Far Field Radiation Sphere栏的设定）。c.使用 Validation check命令进行检验，无错误发生，下一步运行命令 Analyze，对柱锥结构体进行求解。如图4.1.5和4.1.6所示。
上传时间： 2022-03-10
上传用户：
