function disableAllK(){
	document.getElementById('ssf_k1').disabled=true;
	document.getElementById('ssf_k2').disabled=true;
	document.getElementById('ssf_k3').disabled=true;
	document.getElementById('ssf_k4').disabled=true;
}
function enableAllK(){
	document.getElementById('ssf_k1').disabled=false;
	document.getElementById('ssf_k2').disabled=false;
	document.getElementById('ssf_k3').disabled=false;
	document.getElementById('ssf_k4').disabled=false;
 }