function?coe?=?cal_coefficient（Dlsrthita）
%D:換能器寬度
%L:換能器平面距血管的距離；
%r:被校正點對應半徑
%thita:被校正點對應角度
z1=1.632;%1.686
z2=1.656;
c1=1540;
c2=1570;
%?rou1=1.016;%1.084
%?rou2=1.686;
%?L=ls-r*（1-sin（thita））;
%計算校正系數的時候歸到第一象限
if（0????thita=thita;
???elseif（thita<=pi）
????thita=pi-thita;
???elseif（thita<=pi*3/2）
????thita=thita-pi;
???else
????thita=2*pi-thita;
end
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%?thita_in=thita;
%?if（sin（thita_in）*（c2/c1）<0.8）
%?????????thita_r=asin（sin（thita_in）.*（c2/c1））;
%?????????reflect1=z2*cos（thita_in）-z1*cos（thita_r）;
%?????????reflect2=z2*cos（thita_in）+z1*cos（thita_r）;
%?????????reflect=sum（reflect1/reflect2）*0.01;
%?????else
%?????????reflect=0.8;
%?end

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
dthita=0.05;
thita_in=thita-dthita:0.01:thita+dthita;
if（thita+dthita????????thita_r=asin（sin（thita_in）.*（c2/c1））;
????????reflect1=z2.*cos（thita_in）-z1.*cos（thita_r）;
????????reflect2=z2.*cos（thita_in）+z1.*cos（thita_r）;
????????reflect=sum（reflect1./reflect2）*0.01;
????else
????????reflect=0.8;
end
reflect0=（z2-z1）/（z2+z1）;
coe=（1-reflect0）/（1-reflect）;
%?thita1=pi/2-thita-atan（D*sin（thita）/（4*ls*sin（thita）+D*cos（thita）））;
%?thita2=pi/2-thita+atan（D*sin（thita）/（4*ls*sin（thita）-D*cos（thita）））;
%?lambda=1540e-7;
%?n=32;???%?陣元數目
%?d=0.0003048;
%?D_thita=thita1:0.01:thita2;
%?Ds=abs（（sin（n*pi*d*sin（D_thita）/lambda））./（（n*sin（pi*d*sin（D_thita）/lambda））））;
%?u=sum（Ds）*0.01;
%?thita0=atan（D/（4*L））
%?D_thita0=0.001:0.01:thita0;
%?Ds0=abs（（sin（n*pi*d*sin（D_thita0）/lambda））./（（n*sin（pi*d*sin（D_thita0）/lambda））））;
%?u0=2*sum（Ds0）*0.01;
%?%計算反射系數
%?thita_in=pi/2-thita;
%?thita_r=asin（sin（thita_in）*（c2/c1））;
%?reflect（i）=abs（（z2*cos（thita_in）-z1*cos（thita_r））/（z2*cos（thita_in）+z1*cos（thita_r）））;
%?reflect0=（z2-z1）/（z2+z1）;
%?%?coe=u;
%?coe=reflect0*u0/（reflect*u）

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----

?????文件??????49206??2008-04-15?21:50??snake_demo\001.bmp

?????文件???????1969??2010-03-12?10:38??snake_demo\cal_coefficient.asv

?????文件???????1977??2010-03-12?15:10??snake_demo\cal_coefficient.m

?????文件???????5007??2010-03-11?15:21??snake_demo\GVF_Snake.asv

?????文件???????5033??2010-03-11?16:34??snake_demo\GVF_Snake.m

?????文件???????3198??2010-03-01?18:06??snake_demo\GVF_Snake11.asv

?????文件???????3198??2010-03-01?18:11??snake_demo\GVF_Snake11.m

?????文件??????31456??1998-10-02?08:33??snake_demo\head.jpg

?????文件??????14125??2010-01-27?15:23??snake_demo\hs_err_pid2812.log

?????文件??????47490??1999-01-06?13:49??snake_demo\images\chest.pgm

?????文件???????1064??1998-09-30?09:50??snake_demo\images\heart.mat

?????文件??????25615??1998-09-29?10:01??snake_demo\images\heart.pgm

?????文件???????3563??2010-01-25?21:24??snake_demo\images\heart11.mat

?????文件???????4248??1998-09-30?09:58??snake_demo\images\heart2.mat

?????文件???????4056??1998-10-01?06:18??snake_demo\images\heart3.mat

?????文件??????65594??1999-01-06?13:32??snake_demo\images\new.pgm

?????文件???????2792??1998-09-30?10:26??snake_demo\images\room.mat

?????文件???????4109??1997-08-28?12:32??snake_demo\images\room.pgm

?????文件???????2928??1998-09-30?09:43??snake_demo\images\room2.mat

?????文件???????2928??1998-09-30?09:44??snake_demo\images\room3.mat

????..A.SH.??????7680??2010-01-26?15:57??snake_demo\images\Thumbs.db

?????文件???????3304??1998-10-01?06:20??snake_demo\images\u64.mat

?????文件???????4109??1997-08-28?12:32??snake_demo\images\U64.pgm

?????文件???????2952??1998-10-07?04:51??snake_demo\images\u642.mat

?????文件????????135??2010-03-03?09:31??snake_demo\intme.m

?????文件???????1552??2010-03-03?19:34??snake_demo\jiaozheng.asv

?????文件???????1565??2010-03-12?09:49??snake_demo\jiaozheng.m

?????文件???????3798??2009-09-29?16:45??snake_demo\sdemo.m

?????文件??????49206??2010-01-27?16:51??snake_demo\snake\001.bmp

?????文件????????916??2009-09-21?11:00??snake_demo\snake\BoundMirrorEnsure.m

............此處省略66個文件信息