Quality and Investment Decisions in Hospital Care when Physicians are Devoted Workers

This paper analyses the decision to invest in quality by a hospital in an environment where doctors are devoted workers, i.e. they care for specific aspects of the output they produce. We assume that quality is the result of both an investment in new technology and the effort of the medical staff. Hospital services are paid on the basis of their marginal cost of production while the number of patients treated depends on a purchasing rule which discriminates for the level and timing of the investment. We show that the presence of devoted doctors affects the trade-off between investment and the purchasing rule so that for the hospital it is not always optimal to anticipate the investment decision

Recycle of aluminium (A356) for processing of new composites reinforced with magnetic nano iron oxide and molybdenum

© The Society for Experimental Mechanics, Inc. 2017. The microstructural and tribological behavior of Aluminium Matrix Composites (AMCs with scrap A356) reinforced with nano iron oxide (Fe3O4) and Molybdenum (Mo) produced by powder metallurgy was investigated with low cost manufacturing of light and efficient multifunctional materials for aeronautical applications. Molybdenum (Mo) is a refractory material with a high melting temperature and used essentially as high-temperature resistant materials for applications in the fields of aerospace engineering such as rocket nozzles, high-temperature resistant pieces, etc. It shows a low thermal expansion coefficient, excellent electrical conductivity and higher corrosion resistance. However, it becomes very brittle after recrystallization. Generally, AMCs reinforced with magnetic iron (Fe3O4) exhibit good physical (electrical and magnetic) properties, which make them excellent multifunctional lightweight materials. Normally, they do not present high wear resistance. To overcome this shortcoming, very fine Mo (1–3 μm) powders was added to the AMCs. The main purpose of this work is to show the influence of molybdenum on the AMCs reinforced by 10 % of Fe3O4 to increase wear resistance of these novel composites. Matrix/reinforcement interface was also evaluated due to addition of Mo to the matrix. Two groups of composites were prepared: First group contains only Fe3O4, Cu and Mo. Second group contains Fe3O4 doped with TiO2 (thermomechanical treatment), Cu and Mo. For processing, a novel combined method of sintering + forging was performed. Experimental results have revealed that even small additions of Mo can drastically improve wear performance of AMCs reinforced with magnetic iron (Fe3O4). Morphology of the composites was evaluated by Scanning Electron Microscopy (SEM). Scratch tests were conducted to evaluate wear properties