function openwin(){ 
window.open("http://www.powersafety.com.cn/default/bbs/","","")  
} 

function get_cookie(Name) { 
var search = Name + "=" 
var returnvalue = ""; 
if (document.cookie.length > 0) { 
offset = document.cookie.indexOf(search) 
if (offset != -1) { 
offset += search.length 
end = document.cookie.indexOf(";", offset); 
if (end == -1) 
end = document.cookie.length; 
returnvalue=unescape(document.cookie.substring(offset, end)) 
} 
} 
return returnvalue; 
} 

function loadpopup(){ 
if (get_cookie('popped')==''){ 
openwin() 
document.cookie="popped=yes" 
} 
}