Resulting from papers from Algebraic, Extremal and Metric Combinatorics 1986 conference held at the University of Montreal, this book represents a comprehensive overview of the present state of progress in three related areas of combinatorics. Topics covered in the articles include association shemes, extremal problems, combinatorial geometries and matroids, and designs. All the papers contain new results and many are extensive surveys of particular areas of research.

1.1 Life Cycle Assessment (LeA): a fascinating and sophisticated tool The greening of the economy is not a new task, but it is a challenge for which a lot of tasks still have to be done. It is known that the main source of environ mental deterioration by industry is not any more the chimneys and other process related emissions, but the products and services produced. Products are regarded as carriers of polIution: they are not only a potential source of polIution and waste during their use; they are also a cause of resource depletion, energy consumption, and emissions du ring their life...