document.writeln("<a href=\"icaxcds.php?mod=down&amp;did=49\" id=\"down_49\" class=\" dfurl\"  target=\"_blank\">	<img alt=\"\" src=\"static/image/filetype/pdf.gif\" /> : 01.参数化建模或直接建模：为何您可能两者都需要 (943.95 KB)</a>");