function Chk_Email(type) {
 
 var obj_email = document.form.email;
 var struserid = document.form.userid;
 var mailcheck = document.form.mailcheck;
 var tail
   
 if(mailcheck.checked){
  tail = "@kma.or.kr";
        if(struserid.value != ""){
            obj_email.value = struserid.value + tail;
        }else{
            alert('아이디를 입력해주세요');
            struserid.focus();
            mailcheck.checked = false;
          return false;
        }
    }
 else{
        obj_email.value = "";
    }
 return true;
}