这个函数求热传导方程初值问题的解，以输入图像为初始值，输出图像为t时刻的解，输出图像被用来作为去噪的结果-This function for heat conduction equations of the solution of the initial boundary value problems, with input image for the initial value, output image of the solution of the moment for t, output image to be used as a result of the noise