var mywin = null;

function open_window(url) {
mywin = window.open(url,"v_articles",'toolbar=0,location=0,directories=0,status=0,menubar=0,scrollbars=1,resizable=1,width=550,height=360,left=10,top=100');
  focusWindow();
}
function open_window2(url) {
mywin = window.open(url,"v_articles2",'toolbar=0,location=0,directories=0,status=0,menubar=0,scrollbars=1,resizable=1,width=450,height=300');
  focusWindow();
}
function open_window_pdf(url) {
mywin = window.open(url,"v_pdf",'toolbar=0,location=0,directories=0,status=0,menubar=0,scrollbars=1,resizable=1,width=450,height=600');
  focusWindow();
}
function open_window_map(url) {
mywin = window.open(url,"v_map",'toolbar=0,location=0,directories=0,status=0,menubar=0,scrollbars=0,resizable=0,width=550,height=370');
  focusWindow();
}
function open_window_full(url) {
mywin = window.open(url,"_top",'toolbar=1,location=0,directories=0,status=0,menubar=1,scrollbars=1,resizable=1,width=max.avail.Width,height=max.avail.Height');
  focusWindow();
}
function focusWindow(){
  if(!mywin.closed) mywin.focus(); // focus it, if it isn't already closed
  else return // or do whatever you want if it is closed
}
//  mywin.window.focus();