Suchergebnisse

Traditional methods for designing of civil engineering structures and other engineering systems are frequently based on the concept of target probability of failure. However, this fundamental quantity is usually specified on the basis of comparative studies and past experience only. Moreover, probabilistic design methods suffer from several deficiencies, including lack of consideration for accidental and other hazard situations and their consequences. Both of these extreme conditions are more and more frequently becoming causes of serious failures and other adverse events. Available experience clearly indicates that probabilistic design procedures may be efficiently supplemented by a risk analysis and assessment, which can take into account various consequences of unfavourable events. It is therefore anticipated that in addition to traditional probabilistic concepts the methods of advanced engineering design will also commonly include criteria for acceptable risks.

AbstractThe role of mathematical models in engineering design is no longer that of simply automating techniques which were previously carried out manually. Throughout industry models are now becoming accepted as one of the main decision support systems to managers. This is certainly the case in engineering design for managing the environment. We are rapidly moving into the age of expert systems and hydro‐informatics, where the primary aim of most models is decision support. In this paper the role of the models in modern practice is reviewed and illustrated by case histories.

In this article, the authors test the hypothesis that cycles of speaking and turn taking during group design discussions are entrained to rhythmic shifts in group-level modes of reasoning. Video recordings of six teams of engineering students performing realistic design tasks were coded for instances of figural and conceptual reasoning, rates of turn taking, and group participation. Exploratory spectral analysis pointed to rhythmic oscillations every 5 to 10 minutes between periods of predominantly figural or conceptual discussion, whereas structural equations modeling indicated a lead-lag relationship between peaks in figural reasoning and lowered levels of conceptual reasoning, group participation, and turn taking. The authors interpret these results as evidence for cognitive entrainment in group discussion and illustrate the potential of frequency and pooled time series techniques for studying the temporal structure of group interaction.