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A variant of Kohonen's algorithm for the self‐organizing map (SOM) is used to solve a continuous location‐routing problem that can be applied to identify potential sites for subsequent selection by a discrete finite set model. The paper aims to show how the algorithm may be customized to fit the problem structure in a way that allows aspects of location and routing to be integrated into the solution procedure.

A set of test instances is used to compare the solutions of the neural network to those obtained by sequential approaches based on a savings procedure.

Compared to the results of the sequential approaches, the neural network yields good results.

Future work may cover the expansion of the neural approach to multi‐depot and multi‐stage problems. Additionally, application of procedures other than the savings procedure should be evaluated with respect to their potential for further enhancing the solution quality of the sequential approaches.

This paper shows that strategic location decisions in practical applications with long‐term customer relationships can be taken using simultaneously generated routing information on an operational level.

The paper provides a new variety of applications for SOM as well as high quality results for the specific type of problem considered.

In the Norwegian offshore oil industry, helicopters have been used as a major mode of transporting personnel to and from offshore installations for decades. Helicopter transportation represents one of the major risks for offshore employees. The purpose of this paper is to study the safety of helicopter transportation in terms of the expected number of fatalities on an operational planning level.

Based on an analysis of helicopter accidents, this paper proposes a mathematical model that can aid in the planning of routes for the fleet in order to minimize the expected number of fatalities.

A theorem proven in this paper tells that hub-and-spoke configuration is the best way of routing helicopters in terms of minimizing expected number of fatalities. Computational results indicate that the expected number of fatalities may be reduced at the expense of longer travel time by implementing the proposed method into planning of routes for helicopter fleet.

The main limitation is the present inability to solve large problem instances.

The suggested tool is able to provide decision makers with a set of solutions from which they can choose the one with the best trade-off between travel time and transportation safety.

The mathematical model and theoretical results for route planning with a safety-based objective are original.

The purpose of this paper is to assess the likelihood of successfully introducing constitutional changes to the definition of marriage in Germany.

The paper examines the values underpinning the German constitution through academic writing and case law.

Fundamental change is unlikely to occur in the foreseeable future, despite EU case law.

Incremental changes have taken place in all countries. These have begun in the workplace and spread to more fundamental areas such as challenges to marriage definitions in many countries. In a conservative country such as Germany the fact that even the highest constitutional court has come close to opening the door to change can be interpreted to mean the wait will not be too long.

The paper provides a comparative analysis that will highlight the types of arguments that have been successfully pushed through the courts as well as persuading political actors to enact positive legislation.