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xiashaoyan

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zaq123321

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xiashaoyan: ½ð±Ò+5, ¡ïÓаïÖú 2015-09-07 21:12:45
I think the coefficient is less than one makes sense. For diffusion, the concentration decreases as time evolves in general. The total amount of solute keeps constant and cannot be bigger than  the original state.  If the coefficient is bigger than 1, that means something is created during evolution . Not very sure my understanding is correct or not

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2Â¥2015-09-05 19:15:47
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xiashaoyan

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2Â¥: Originally posted by zaq123321 at 2015-09-05 19:15:47
I think the coefficient is less than one makes sense. For diffusion, the concentration decreases as time evolves in general. The total amount of solute keeps constant and cannot be bigger than  the o ...

ÄãÕâÖÖÀí½â£¬ÎÒÒ²Ïë¹ý£¬µ«ÊÇÎÒÓÐÒ»¸öÒÉÎÊ¡£ÄÃPMÄ£ÐÍÀ´Ëµ£¬PMµÄÀëÉ¢ÐÎʽΪ£ºI(x,y)^(t+1)=I(x,y)^t+¦Ë(CN ∇N I+CS ∇S I+CW ∇W I++CE ∇E I)£¬Èç¹ûҪÿ´Îµü´ú±£³ÖI(x,y)^(t+1)<I(x,y)^t,ÄÇôºóÃæÓ¦¸ÃÏî¦Ë(CN ∇N I+CS ∇S I+CW ∇W I++CE ∇E I)Ó¦¸ÃÊÇСÓë0 £¬µ«ÊÇÕâ¸öºÍÀ©É¢ÏµÊýÈ¡´óÓÚ1ºÍСÓë1ÓÐʲô¾ßÌå¹ØÏµÂð£¿Èç¹ûÀ©É¢ÏµÊý<1,ÄÇôºóÃæÏî¾ÍÄܱ£Ö¤Ð¡Óë1Âð£¿À©É¢ÏµÊý>1ÊУ¬¾Í²»¿ÉÒÔÂð£¿
3Â¥2015-09-07 21:16:40
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zaq123321

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You cannot guarantee I (t+1)<I (t). That's also not correct. Diffusion means mixture. So some will increase some will decrease

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