function [alpha,N,U]=youxianchafen2(r1,r2,up,under,num,deta) %[alpha,N,U]=youxianchafen2(a,r1,r2,up,under,num,deta) %该函数用有限差分法求解有两种介质的正方形区域的二维拉普拉斯方程的数值解 %函数返回迭代因子、迭代次数以及迭代完成后所求区域内网格节点处的值 %a为正方形求解区域的边长 %r1,r2分别表示两种介质的电导率 %up,under分别为上下边界值 %num表示将区域每边的网格剖分个数 %deta为迭代过程中所允许的相对误差限 n=num+1; %每边节点数 U(n,n)=0; %节点处数值矩阵 N=0; %迭代次数初值 alpha=2/(1+sin(pi/num));%超松弛迭代因子 k=r1/r2; %两介质电导率之比 U(1,1:n)=up; %求解区域上边界第一类边界条件 U(n,1:n)=under; %求解区域下边界第一类边界条件 U(2:num,1)=0;U(2:num,n)=0; for i=2:num U(i,2:num)=up-(up-under)/num*(i-1);%采用线性赋值对上下边界之间的节点赋迭代初值 end G=1; while G>0 %迭代条件：不满足相对误差限要求的节点数目G不为零 Un=U; %完成第n次迭代后所有节点处的值 G=0; %每完成一次迭代将不满足相对误差限要求的节点数目归零 for j=1:n for i=2:num U1=U(i,j); %第n次迭代时网格节点处的值 if j==1 %第n+1次迭代左边界第二类边界条件 U(i,j)=1/4*(2*U(i,j+1)+U(i-1,j)+U(i+1,j)); end if (j>1)&&(j U2=1/4*(U(i,j+1)+ U(i-1,j)+ U(i,j-1)+ U(i+1,j)); U(i,j)=U1+alpha*(U2-U1); %引入超松弛迭代因子后的网格节点处的值 end if i==n+1-j %第n+1次迭代两介质分界面（与网格对角线重合）第二类边界条件 U(i,j)=1/4*(2/(1+k)*(U(i,j+1)+U(i+1,j))+2*k/(1+k)*(U(i-1,j)+U(i,j-1))); end if j==n %第n+1次迭代右边界第二类边界条件 U(i,n)=1/4*(2*U(i,j-1)+U(i-1,j)+U(i+1,j)); end end end N=N+1 %显示迭代次数 Un1=U; %完成第n+1次迭代后所有节点处的值 err=abs((Un1-Un)./Un1);%第n+1次迭代与第n次迭代所有节点值的相对误差 err(1,1:n)=0; %上边界节点相对误差置零 err(n,1:n)=0; %下边界节点相对误差置零 G=sum(sum(err>deta))%显示每次迭代后不满足相对误差限要求的节点数目G end
标签： 有限差分
上传时间： 2018-07-13
上传用户：Kemin
能直接浏览如尼康、佳能原片NEF照片，无需安装，绿色软件。
上传时间： 2019-02-16
上传用户：yzmhm
Reconstruction- and example-based super-resolution (SR) methods are promising for restoring a high-resolution (HR) image from low-resolution (LR) image(s). Under large magnification, reconstruction-based methods usually fail to hallucinate visual details while example-based methods sometimes introduce unexpected details. Given a generic LR image, to reconstruct a photo-realistic SR image and to suppress artifacts in the reconstructed SR image, we introduce a multi-scale dictionary to a novel SR method that simultaneously integrates local and non-local priors. The local prior suppresses artifacts by using steering kernel regression to predict the target pixel from a small local area. The non-local prior enriches visual details by taking a weighted average of a large neighborhood as an estimate of the target pixel. Essentially, these two priors are complementary to each other. Experimental results demonstrate that the proposed method can produce high quality SR recovery both quantitatively and perceptually.
标签： Super-resolution Multi-scale Dictionary Single Image for
上传时间： 2019-03-28
上传用户：fullout
stm32工程模板
上传时间： 2019-05-30
上传用户：Lily_liu
1/4-inch, 5-Megapixel SOC Image Sensor Optimized for High-Volume Mobile Markets
上传时间： 2019-09-29
上传用户：wsgq2019
STC单片机资料 请用逗号分隔标签 * 资料描述：
上传时间： 2019-12-02
上传用户：hjd0303
fds 选择文件 X 飞行器半实物仿真初案_
上传时间： 2020-03-06
上传用户：stormfree
Cooperation has been the subject of intensive study in the social and biological sciences, as well as in mathematics and artificial intelligence. The fundamental finding is that even egoists can sustain cooperation provided the structure of their environment allows for repeated interactions (Axelrod 1984).
标签： Cooperation Wireless Networks in
上传时间： 2020-05-27
上传用户：shancjb
Mobile multimedia communication is increasingly in demand because of the basic need to communi- cate at any time, anywhere, using any technology. In addition, to voice communication, people have a desire to access a range of other services that comprise multimedia elements—text, image, animation, high fidelity audio and video using mobile communication networks. To meet these demands, mobile communication technologies has evolved from analog to digital, and the networks have passed through a number of generations from first generation (1G) to fourth generation (4G).
标签： Communications Multimedia Concepts Mobile
上传时间： 2020-05-30
上传用户：shancjb
This book intends to prepare you to define Unified Communications (UC) for yourself and then get it to work for you. Each vendor pulls together from its available products a package of features related to voice, data, messaging, and image communications. That’s UC for one vendor, but it’s unlikely to match exactly the UC from another vendor. You need a detailed specification to know what you’ll see installed.
标签： Communications Unified VoIP and
上传时间： 2020-06-01
上传用户：shancjb
