function open_window(page,height,width)
				{
					
					var H = (screen.height - height) / 2;
					
					var L = (screen.width - width) / 2;
					pop_up = window.open(page,"Popup","status=yes,scrollbars=yes,resizable=yes,height="+height+",width="+width+",top="+H+",left="+L);
				}