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
淋浴器温度控制调节采用MAT LAB 的附加组件Simulink, 仿真系 统的框图如图1 所示。图中的虚线为模糊控制器, 作为二维模糊控制器机构以水的温度偏差temp 和 流量偏差f low 为输入量, 采用模糊推理方法对水 的温度偏差和流量偏差进行整定, 用来确定冷水阀 门和热水阀门的开口大小cold 和hot 以便控制冷 热水的流量, 构成2 输入2 输出的一阶模糊控制系 统; 模糊推理与去模糊化采用MIN - MAX 法及重 心法, 并用MA TLAB 模糊推理工具箱来编辑模糊 控制器。 图1
上传时间: 2018-10-12
上传用户:一只虫虫
网络中基于IEEE 1588,由多个节点和多元化的连接,每个连接连接至少两个节点允许节点之间的通信,包括根据网络协议的消息交换,IEEE 1588的同步提高,允许多个主时钟系统中同时操作。为此,根据IEEE 1588标准,许多节点组成一个实现高可用性主时钟的子系统。
上传时间: 2019-04-25
上传用户:AoBa77
# include<stdio.h> # include<math.h> # define N 3 main(){ float NF2(float *x,float *y); float A[N][N]={{10,-1,-2},{-1,10,-2},{-1,-1,5}}; float b[N]={7.2,8.3,4.2},sum=0; float x[N]= {0,0,0},y[N]={0},x0[N]={}; int i,j,n=0; for(i=0;i<N;i++) { x[i]=x0[i]; } for(n=0;;n++){ //计算下一个值 for(i=0;i<N;i++){ sum=0; for(j=0;j<N;j++){ if(j!=i){ sum=sum+A[i][j]*x[j]; } } y[i]=(1/A[i][i])*(b[i]-sum); //sum=0; } //判断误差大小 if(NF2(x,y)>0.01){ for(i=0;i<N;i++){ x[i]=y[i]; } } else break; } printf("经过%d次雅可比迭代解出方程组的解:\n",n+1); for(i=0;i<N;i++){ printf("%f ",y[i]); } } //求两个向量差的二范数函数 float NF2(float *x,float *y){ int i; float z,sum1=0; for(i=0;i<N;i++){ sum1=sum1+pow(y[i]-x[i],2); } z=sqrt(sum1); return z; }
上传时间: 2019-10-13
上传用户:大萌萌撒
High-Speed, Low-Power Dual Operational Amplifier The AD826 features high output current drive capability of 50 mA min per amp, and is able to drive unlimited capacitive loads. With a low power supply current of 15 mA max for both amplifiers, the AD826 is a true general purpose operational amplifier. The AD826 is ideal for power sensitive applications such as video cameras and portable instrumentation. The AD826 can operate from a single +5 V supply, while still achieving 25 MHz of band width. Furthermore the AD826 is fully specified from a single +5 V to ±15 V power supplies. The AD826 excels as an ADC/DAC buffer or active filter in data acquisition systems and achieves a settling time of 70 ns to 0.01%, with a low input offset voltage of 2 mV max. The AD826 is available in small 8-lead plastic mini-DIP and SO packages.
上传时间: 2020-04-19
上传用户:su1254
A wireless communication network can be viewed as a collection of nodes, located in some domain, which can in turn be transmitters or receivers (depending on the network considered, nodes may be mobile users, base stations in a cellular network, access points of a WiFi mesh etc.). At a given time, several nodes transmit simultaneously, each toward its own receiver. Each transmitter–receiver pair requires its own wireless link. The signal received from the link transmitter may be jammed by the signals received from the other transmitters. Even in the simplest model where the signal power radiated from a point decays in an isotropic way with Euclidean distance, the geometry of the locations of the nodes plays a key role since it determines the signal to interference and noise ratio (SINR) at each receiver and hence the possibility of establishing simultaneously this collection of links at a given bit rate. The interference seen by a receiver is the sum of the signal powers received from all transmitters, except its own transmitter.
标签: Stochastic Geometry Networks Wireless Volume and II
上传时间: 2020-06-01
上传用户:shancjb
对连续信号 ( , , )进行理想采样,可得采样序列 。下图给出了 的幅频特性曲线,由此图可以确定对 采用的采样频率。
上传时间: 2020-12-26
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USR-15X系列产品说明书USR-15X系列体积虽小,功能不少:免插卡上电即联网,配合外置卡槽,双卡切换更可靠!蓝牙配微信小程序扫一扫,快速配置参数,告别电脑和串口线!灵活装标准导轨卡扣和隐藏式挂耳,安装灵活自如!
上传时间: 2021-12-09
上传用户:trh505
索尼最小CMOS图像传感器IMX415 日本东京索尼公司今年发布一款新型CMOS影像传感器:IMX415,1/2.8 英寸堆叠式4K CMOS影像传感器,刷新全球同类产品的小尺寸纪录; 针对日益扩大的智慧城市相关的市场需求,索尼特别开发了这款新型的应用于安防摄像机的传感器,以满足安防摄像机在防盗、灾难警报、交通监测系统或商业综合体等多种监控应用领域的快速增长需求。目前,在各种场合安装安防摄像机的需求正日益增多,而对于可以安装在任何地方、具有更高图像识别和检测性能的紧凑型安防摄像机的需求也比以往任何时候都要大。未来,用于异常检测和人工智能行为分析的图像识别摄像机的需求也将显著增长。 为了满足这一需求,索尼推出了一系列紧凑型4K CMOS影像传感器,能够同时提供卓越的图像识别和检测性能,以及出色的低光性能表现——这是传统技术难以实现的。索尼丰富的传感器产品线,让人们在多种场景下都能获取高质量图像,从而扩大了安防摄像机的应用范围。IMX415堆叠式CMOS影像传感器采用了索尼独有的高灵敏度,低噪点技术,将像素尺寸缩至1.45平方微米,比前代产品*3缩小约80%,尽管该传感器只有1/2.8英寸,其低光性能却是前代产品的1.5倍*3。缔造出破纪录的 1/2.8英寸堆叠式4K CMOS影像传感器,并具备卓越的低光性能。该传感器采用低噪点电路堆叠式结构,即使在黑暗环境下也可以捕捉到清晰的图像。由于它尺寸小,可适用于多种场景,在安防摄像机应用方面需求量很高。
上传时间: 2021-12-13
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CHAPTER 1: THE OP AMP CHAPTER 2: OTHER LINEAR CIRCUITS CHAPTER 3: SENSORS CHAPTER 4: RF/IF CIRCUITS CHAPTER 5: FUNDAMENTALS OF SAMPLED DATA SYSTEMS CHAPTER 6: CONVERTERS CHAPTER 7: DATA CONVERTER SUPPORT CIRCUITS CHAPTER 8: ANALOG FILTERS CHAPTER 9: POWER MANAGEMENT CHAPTER 10: PASSIVE COMPONENTS CHAPTER 11: OVERVOLTAGE EFFECTS ON ANALOG INTEGRATED CIRCUITS CHAPTER 12: PRINTED CIRCUIT BOARD (PCB) DESIGN ISSUES CHAPTER 13: DESIGN DEVELOPMENT TOOLS
上传时间: 2021-12-21
上传用户:wangshoupeng199