Real Knowledge Undermining Luck

Based on the discussion of a novel version of the Barn County scenario, the paper argues for a new explication of knowledge undermining luck. In passing, an as yet undetected form of benign luck is identified

Non-proportional deformation paths for sheet metal: experiments and models

For mild steel, after significant plastic deformation in one direction, a subsequent deformation in an orthogonal direction shows a typical stress overshoot compared to monotonic deformation. This phenomenon is investigated experimentally and numerically on a DC06 material. Two models that incorporate the observed overshoot are compared. In the Teodosiu-Hu model, pre-strain influences the rate of kinematic hardening by a rather complex set of evolution equations. The shape of the elastic domain is not changed. Another way to describe the observed overshoot is by distortional hardening, like in the model by Levkovitch et al. In this model, a deformation in one direction directly influences the shape of the yield locus, which is apparent even without additional plastic deformation in another direction. Both models can represent the experimental results well, but in the original implementations, the Teodosiu model performs better.\ud \ud KEYWORDS: non-proportional loading, plasticity, material model, distortional hardenin

Consistent plane stress-3D conversion of hardening models and yield criteria

Material models in FE-simulations are used both in 3D and plane stress situations. In this\ud paper it is shown that for models that include kinematic hardening, the conversion from a 3D to a plane\ud stress algorithm needs more adaptations than only eliminating the thickness components. An example\ud and a consistent conversion are presented. Secondly it is discussed how to convert a 2D plane stress\ud yield criterion into a full 3D yield criterion. This is essential for using solid-shell elements with 2D yield\ud criteria, typically used in sheet metal formin

DAS28: a useful instrument to monitor infliximab treatment in patients with rheumatoid arthritis

The Disease Activity Score using 28 joint counts (DAS28) has been developed in a cohort of patients with rheumatoid arthritis in which only conventional anti-rheumatic treatments were used. It has extensively been validated to monitor disease activity in daily clinical practice as well as in clinical trials. The study of Vander Cruyssen and colleagues showed that the DAS28 correlated best with the decisions of rheumatologists to increase the infliximab dose because of insufficient response. This result once more confirms the validity of the DAS28 to monitor disease activity in patients with rheumatoid arthritis and to titrate treatment with biologicals

Evaluation of stresses in a combined plane strain-simple shear test

A biaxial testing device for sheet metal has been developed that can impose a combination of\ud plane strain and simple shear deformation. The specimen has a large width to height ratio and a small height\ud to thickness ratio. The forces in tensile and shear direction are easily measured and the tensile stress and shear\ud stress can easily be derived. For a full description of stresses, however, the stress in lateral direction should also\ud be known. This stress is a result of the constraint, imposed by the large width to height ratio and cannot be\ud measured directly. The strain in the specimen is measured on the surface. By imposing the Drucker normality\ud principle, the direction of the tangent to the yield surface is known and the unknown stress increment in lateral\ud direction can be obtained. Computer simulations are performed to test whether the intended approach can\ud recalculate all stress components from measurement of 3 in-plane strains and just 2 stresses. Without hardening,\ud good results are obtained for a complete interval between the pure shear point up to a point between uniaxial\ud stress and the plane strain point on the yield locus. With hardening, the algorithm requires a lot of data points\ud to avoid drifting from the exact solution. It is noted that, although the normality rule is used, it is not necessary\ud to have an a-priori knowledge of the yield functio

New service development in high tech sectors: a decision making perspective

Many service companies active in high tech sectors have implemented largely decentralized decision architectures in their innovation processes. This is done to improve responsiveness under extremely dynamic and uncertain business conditions. As a consequence of the empowerment of decision-makers at the product management level, the success of the New Service Development (NSD) process will increasingly depend on individual product managers’ information processing and decision-making performance. The present study investigates antecedents of decision-making effectiveness in the high tech NSD process, and reports on a case study performed in the mobile telecommunication services industry. NSD project managers’ unique task conditions are articulated, and some antecedents and moderators of effective decision-making are identified in a study of four innovation projects. Findings are integrated in a theoretical framework. The study reveals the crucial role of decision-makers’ flexible use of various cognitive styles, their proactive attitude, and their capability to mentally represent innovation interfaces with the customer, the technology and the firm. Managerial implications and suggestions for further research are provided.management and organization theory ;