Book reviews

Wellstead has assembled in this book the basic concepts of network modelling, variational modelling and bond graph methods with energy being the unifying concept. The author acknowledges the fact that he has drawn extensively from (1) introduction to Systems Dynamics by J. L. Shearer, A. T. Murphy and H. H. Richardson, (2) Dynamics of Mechanical and Electromechanical Systems by S. H. Crandall, et al., and (3) Analysis and Design of Engineering Systems by H. M. Paynter. For the purposes of serving as a text, Wellstead´s book is disappointing in that it does not provide sufficient discussion and examples in Part 1: Basics and Part 2: Systematic Modelling Methods. For example, the presentations of fundamental concepts by Shearer, et al., and Crandall, et al., as well as that given by K. Ogata in Systems Dynamics, contain considerably more explanation than that given by Wellstead.