Renfrey B. Potts

Boundary Contraction Solution of Laplace's Differential Equation II

A numerical method is introduced for solution of the Dirichlet problem within a circle. The data prescribed on the original boundary is used to compute the solution at mesh points on a concentric circle of slightly smaller radius, thereby defining another boundary value problem over the smaller circle. The solution for the entire region is obtained by successive contractions of the boundary in this way. Appropriate approximating relations are presented and their stability is discussed.

Letter to the Editor—Report on the Fourth International Symposium on the Theory of Traffic Flow

The Fourth International Symposium on the Theory of Traffic Flow was held in Karlsruhe, Germany, June 18--20, 1968 and was attended by 154 participants from Australia, Austria, Belgium, Czechoslovakia, Denmark, France, Germany, Holland, India, Israel, Italy, Japan, Norway, Portugal, Spain, Sweden, Switzerland, United Kingdom, and the United States of America. The Symposium was organized by Professor W. Leutzbach and held at the Lehrstuhl fur Verkehrswesen, Universitat (TH) Karlsruhe. A total of 40 papers were presented in the six sessions of the Symposium.