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A sensitivity study was performed with a nonlinear elastic finite element model for monotonie analyses of wood-framed shear walls. The objective was to provide information about simplifying a model of wood-framed shear walls with no significant loss in accuracy. The simplifications concern features such as slips in joints between frame members, slips in hold-down connections, and bearing between adjacent sheathing panels. The results from analyses of a shear wall with an opening of window shape show that the effect of constraint by the bearing between sheathing panels and slips in frame joints on the overall stiffness of the wall is limited. Thus, there are great possibilities for reducing the calculation time by not taking these phenomena into account, avoiding an excessive number of degrees of freedom and iterations. The influence of the simplifications on the distribution of vertical reaction forces along the wall is more significant. Furthermore, if each simplification is introduced separately, the effect on the overall stiffness is greater. The difference, however, is less than 10%. The failing pattern of the nail connections is also clearly influenced by the simplifications when they are introduced separately. The results from the analyses show that slips in frame joints can be sufficiently represented by those in connection with the opening.  相似文献   
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A fundamental assumption of theories of decision-making is that we detect mismatches between intention and outcome, adjust our behavior in the face of error, and adapt to changing circumstances. Is this always the case? We investigated the relation between intention, choice, and introspection. Participants made choices between presented face pairs on the basis of attractiveness, while we covertly manipulated the relationship between choice and outcome that they experienced. Participants failed to notice conspicuous mismatches between their intended choice and the outcome they were presented with, while nevertheless offering introspectively derived reasons for why they chose the way they did. We call this effect choice blindness.  相似文献   
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Fisheries management and sustainability assessment of fisheries more generally have recently expanded their scope from single‐species stock assessment to ecosystem‐based approaches, aiming to incorporate economic, social and local environmental impacts, while still excluding global‐scale environmental impacts. In parallel, Life Cycle Assessment (LCA) has emerged as a widely used and recommended framework to assess environmental impacts of products, including global‐scale impacts. For over a decade, LCA has been applied to seafood supply chains, leading to new insights into the environmental impact of seafood products. We present insights from seafood LCA research with particular focus on evaluating fisheries management, which strongly influences the environmental impact of seafood products. Further, we suggest tangible ways in which LCA could be taken up in management. By identifying trade‐offs, LCA can be a useful decision support tool and avoids problem shifting from one concern (or activity) to another. The integrated, product‐based and quantitative perspective brought by LCA could complement existing tools. One example is to follow up fuel use of fishing, as the production and combustion of fuel used dominates overall results for various types of environmental impacts of seafood products, and is also often linked to biological impacts of fishing. Reducing the fuel use of fisheries is therefore effective to reduce overall impacts. Allocating fishing rights based on environmental performance could likewise facilitate the transition to low‐impact fisheries. Taking these steps in an open dialogue between fishers, managers, industry, NGOs and consumers would enable more targeted progress towards sustainable fisheries.  相似文献   
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Migration and chemical availability of 137Cs and90Sr in the long-term was studied on a36-yr-old deposition experiment on pastureconsisting of a sandy soil and a clay soil,contaminated in 1961 with radionuclides in aqueoussolution. Comparisons were made with a study of thesame soils in 1967. Soil samples to 55 cm depth wereanalysed for 137Cs and 90Sr to establish thevertical distribution. Chemical availability wasstudied using sequential extractions with H2O,NH4Ac, NH2OH·HCl, H2O2 andHNO3. Both 137Cs and 90Sr were found atall depths in both soil types. Cs-137 waspredominantly retained within the upper 10 cm (70%)in both soils. For 90Sr, the soils differedsignificantly, retention within the upper 10 cm was27% in sandy soil and 47% in clay soil. Migrationsince 1967 was faster in the sandy soil for bothnuclides. More than 95% of 137Cs was bound inthe acid-digestible and residual fractions in bothsoils. The residual fraction was larger in clay soil.90Sr was highly available in both soils. Noresidual fraction was found, and the easilyexchangeable fraction was 63–75%.  相似文献   
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