EDITORIAL
Methods and concepts for the multi-criteria synthesis of ship structuresThe basic concepts and methods for multi-criteria synthesis of complex thin-walled ship structures in concept and preliminary design are presented. The principal steps in the definition of the design model, the selected general requirements on the design procedure and balanced and applicable combinations of design models are elaborated. The paper also provides an introduction to the basic theory, mappings, non-dominance concepts (Pareto frontier), spaces and sets used for the mathematical definition of design problems (DPs) together with the unified taxonomy applicable in the handling of complex DPs. System identification from the multi-stakeholder perspectives of owner and society and the formulations and solutions of structural DP are discussed.Keywords: design support system (DeSS); Pareto-supported decision making (PSD); thin-walled ship structures; structural design procedure; structural optimisation; Pareto optimality; design synthesis This introductory paper is devoted to my colleague and friend Professor Owen F. Hughes with whom I have had the privilege of sharing the burden and enjoyment of generating methods for the design of efficient and safe ship structures.
ForewordIt has been claimed that this century in engineering will be the century of synthesis, after the twentieth century generated fast and reliable analysis methods capable of dealing with complex structural problems. Synthesis introduces the additional level of complexity, encapsulating the analysis models (AMs). For the synthesis problems, there is no universal technique (like finite element method (FEM) in structural analysis) to solve the non-linear, fuzzy, multi-criteria DP of high dimensionality leading to the multiplicity of different solutions/methods.Most of the papers in this SAOS Special Issue come from the structural analysis area. It is an objective of this introductory paper to systematise some of the basic concepts and methods of synthesis, applicable to the realistic ship structural DPs.Available design methods and optimisation techniques also confirm that analysis methods, as presented in this issue, as well as many methods from other authors can be included into the modern design environments and prove that the 'added level of complexity' is within our reach. For these reasons, this editorial is also an attempt to introduce a novel design-oriented point of view to the interested reader, because we all have as an ultimate objective of our respective work a contribution to the design of efficient and safe structures. This special issue is concluded by the autobiographical essay written by Professor Owen Hughes showing the evolution of concepts and methods from his lifetime experience, supported and augmented by recollections from some of his colleagues and friends. In the field of Naval Architecture, it was Owen Hughes who recognised that the utmost simplicity of methods and clarity of ideas are needed in order to apply the 'first principles anal...