Acta Mechanica Sinica     2011 27 (1):  1-1    ISSN: 0567-7718  CN: 11-2063/O3 Foreword J. Awrejcewicz Department Automation and Biomechanics, Technical University of Lodz, Poland Received: 2011-01-06  Revised: 2010-09-20  Online: 2011-02-25 Supporting info null