In this work, the design of supply chains with reverse flows is studied in a multi-objective context. A MILP model is developed for the optimization of the supply chain structures where both environmental impacts and costs are considered. An optimal Pareto front is obtained that plays an important role in evaluating the best locations of all the entities in the supply chain while accounting for the global supply chain environmental impacts. A study based on a Portuguese glass industry is presented to corroborate both the applicability and the adequacy of the model.

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The progressive collapse of structures generally results in the loss of human lives. Experience shows that flat slab structures are very sensitive to progressive collapse, which may cause serious accidents if special detailing is not provided. The post-punching behaviour of a column-supported slab is decisive in the progressive collapse development. This work presents the experimental research carried out to study the post-punching behaviour of prestressed concrete flat slabs. Six reduced-scale prestressed concrete flat slab models were tested. The tests were carried out in two different phases. In the first phase the models were loaded up to failure by punching. Afterwards, the models were loaded again to study the post-punching behaviour changes caused by the presence of unbonded, prestressed tendons and the influences of their distance to the column.

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A proposal for a reference curriculum for teaching Collaborative Networks at university level is introduced. This curriculum is based on the experience of the authors in teaching and disseminating corresponding concepts in the context of several international projects as well as on the findings of a survey conducted worldwide. A set of teaching units and the corresponding content are introduced. Guidelines for the application of the curriculum are given. A set of experiments and projects are also suggested as a support for the accompanying hands-on lab work. Finally, one concrete experience of application of the proposed curriculum is described.

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Sauropods are often considered to have very limited mobility and reduced limb flexibility, mainly due to their giant size and consequent weight. In the Upper Jurassic Lourinhã Formation, central-west Portugal, deep vertical natural casts of sauropod manus tracks are often preserved as the infills of the original tracks. These manus tracks are vertical-walled, with marks of the striations of the skin scales, showing that the movement of the sauropod manus impacting and exiting the mud was totally vertical with no horizontal component of the stride. Some tracks are up to 66 cm deep, which is equivalent to the height of whole sauropod manus. This means that sauropods could lift their anterior feet in a complete vertical manner. Such movement is only possible if there is mobility at elbow and shoulder articulations in a higher degree than previously thought for sauropods. Our vision of sauropod limbs as inflexible columns has to be updated to a more dynamic model for limbs and body.

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Two techniques (stone-splitters and demolition agents) are revealed to be efficient methods for breaking large stone blocks in extreme paleontological excavation. In certain conditions – where security factors, permission issues, terrain conditions, rock properties are problematic – the traditional methods for breaking large rock blocks cannot be applied (e.g. crane trucks or explosives). Using an expansive demolition agent or stone-splitters after drilling equidistant holes not only allows a cheap, quick and safe solution but also permits precise removal of up to 9 ton blocks. Stone-splitters are a three-part tool that when inserted linearly and equidistantly along a brittle rock mass cause a precise fracture.

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The material in analysis is the skull of an Ornitiquous Psittacosaurus of the China Cretaceous suspicious of being a fraud. The fossil described here appeared to be in very good condition and conservation. The skull is almost complete but because it is filled by sediment, this prevents an analyse of the intra-skull anatomy.
With the intuition of confirming or not the existence of fossiled bone elements in the interior of the sedimented mass that filled the Psittacossaurus skull, it was submitted to a Computorized Tomography.
The Psittacosaurus skull showed an unexpected absorption of the x-rays, because of the outstanding differences of density between the bone and the matrix due to the fact that the interior of the skull was composed by an amalgam of materials, where a less compact and relatively homogeneous material (soil and wax) was found and that material united and mounted the whole skull and the normal bone structures were non-existing.
The capacity of the Computorized Axial Tomography of differentiating materials with different densities of absorption of x-rays, permitted an easy and reliable investigation and explained beyond doubt the quality of the fossil specimen studied, concluding with no doubt that in spite of the realistic aspect, we had come before a fraud.

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