PRACTICAL ASPECTS OF SHAKER MEASUREMENTS FOR MODAL TESTING
Shaker testing is commonly used as a method for measuring forced input in experimental modal analysis. The setup of conventional shakers, stingers and transducers is often the source of test difficulties and avoidable measurement errors. This paper reviews the basic design of shakers as beneficial to modal testing, and the common problems associated with setup issues and resulting measurement errors. These include shaker selection, shaker alignment, stinger selection, connections, reciprocity assumptions and other common mishaps and misunderstandings.
Selective sensitive finite element model updating: an improved approach
This paper discusses the realization of dynamic excitations that are used to complete finite element model updating, based on the selective sensitivity approach. It is explained how structures with many DOFs respond in desired parameter (in‐) sensitive output patterns and how such patterns can be achieved without substantial previous theoretical knowledge. The excitation of selective sensitive response patterns has been defined in the literature as the fundamental requirement to perform parameter (in‐) sensitive model updating. Up to now, the practical generation of selective sensitive response patterns on existing and possible complex structures has been questionable. Consequently, in this paper, a major effort is dedicated to overcome this problem and to provide an excitation approach that can be realized in practice. In a test example, the system parameters of a continuous steel beam are identified, taking into account the minimum excitation configuration given by four available electro dynamic shakers. The realization of different and independent experimental configurations is shown. Copyright © 2014 John Wiley & Sons, Ltd.
Climate change, disasters and electricity generation
Abbrevia ons Foreword 1. Introduc on 8 2. The impacts of changing climate pa erns and changing disaster risks on energy 9 op ons and electricity genera on infrastructure 2.1 The rela onship between climate change and disaster risks 10 2.2 The impact of changing climate pa erns and changing disaster risks on electricity 11 genera on from fossil fuels 2.3 The impact of changing climate pa erns and changing disaster risks on electricity 14 from nuclear power 2.4 The impact of changing climate pa erns and changing disaster risks on electricity 17 genera on from renewable energy 2.4.1 Hydropower 17 2.4.2 Wind Energy 19 2.4.3 Bioenergy 22 2.4.4 Solar Energy 24 3. Climate change and changing disaster risks: implica ons for energy policy and 26 planning