THE LEAN SIX SIGMAAPPROACH FOR PROCESS IMPROVEMENT: A CASE STUDY IN A HIGH QUALITY TUSCANY WINERY

This paper describes the application of a Lean Six Sigma (LSS) project to a winemaking process in a high-quality, Italian winery. LSS is used to focus on the problem through a quantitative analysis of waste and quality performances. The LSS basic algorithm (called “DMAIC”) helps to detect and quantify critical aspects of the process for transferring liquid used in the cellar. The improvement solution is developed and applied through the modification of the cellar system and the process procedure. The results obtained with this solution are shown and discussed in this paper, so too the long term reliability of the improved process analyzed. The results obtained by this case study can help to understand the importance of the LSS method to drive the improvement of agricultural and agrofood productions also in terms of environmental impact which is strongly connected to waste reduction

Computation of Relative 1-Cohomology Generators From a 1-Homology Basis for Eddy Currents Boundary Integral Formulations

Efficient boundary integral formulations based on stream functions for solving eddy current problems in thin conductors, which are modeled by the orientable combinatorial two-manifold with boundary, need generators of the first relative cohomology group to make the problem well defined. The state-of-the-art technique is to compute directly the relative cohomology generators with a combinatorial algorithm having linear worst-case complexity. In this paper, we propose to compute the relative cohomology generators from the homology generators, introducing a novel and general algorithm whose running time is again linear in the worst case. The advantage is that one may use an off-the-shelf software to compute the homology generators and implement only a simple and cheap procedure to obtain the required relative cohomology generators. Although the presented applications relate to ac power systems, the proposed technique is of general interest, and may be used for other applications in computational science and engineering. \ua9 2016 IEE

Hingeless arm for space robotics actuated through shape memory alloys

Operating outside the spacecraft via remotely controlled structures is an important opportunity in different space applications. The research in this area is focused on designing robots that are sufficiently flexible to allow inspection in locations where access is difficult or impossible for astronauts, while minimizing weight and bulk. The purpose of the research is to design a borescope for space applications with no hinges or other mechanisms, exploiting biomimetic design concepts. This is pursued by giving to the borescope a backbone exoskeleton provided by a continuous structure made of fibre reinforced composite material and using NiTi wires as tendons, taking advantage of their low weight and dimensions, which allow them to be embedded between the composite layers during the lamination process. After a study of the state of the art of flexible structures, concentrated in the medical and robotic fields, the research work unfolded in two phases. In the first design phase, several composite layup solutions were considered and analysed using finite element models, leading to the definition of the borescope geometrical parameters and to an initial estimate of the displacements that can be achieved. In the second experimental phase, seven prototypes were produced and tested, with one or more wires, to validate the design and to search for a configuration that can be actuated in different directions. The borescope prototypes resulted flexible enough to achieve an extended degree of bending and at the same time sufficiently rigid to allow complete rearm of the NiTi wires. The numerical and experimental study led to the definition of the design parameters, the number of wires, and the manufacturing technique to integrate NiTi actuators

3D-printed scaffold composites for the stimuli-induced local delivery of bioactive adjuncts

Polysaccharide scaffolds have been successfully employed to reconstruct environments that sustain skin tissue regeneration after injuries. Three-dimensional (3D) advanced additive manufacturing technologies allow creating scaffolds with controlled and reproducible macro- and micro-structure that improve the quality of the restored tissue to favor spontaneous repair. However, when persistent inflammation occurs, the physiological tissue healing capacity is reduced, like in the presence of pathologies like diabetes, vascular diseases, chronic infection, and others. In these circumstances, the bioavailability of therapeutic adjuncts like the growth factors in addition to the standard treatments represents undoubtedly a promising strategy to accelerate the healing of skin lesions. Precisely designed polysaccharide scaffolds obtained by 3D printing represent a robust platform that can be further implemented with the controlled delivery of bioactive adjuncts. Human elastin-like polypeptides (HELPs) are stimuli-responsive biopolymers. Their structure allows the integration of domains endowed with biological functionality, making them attractive compounds to prepare composites with smart properties. In the present study, 3D-printed alginate and chitosan scaffolds were combined with the HELP components. The HELP biopolymer was fused to the epidermal growth factor (EGF) as the bioactive domain. Different constructs were prepared and the stimuli-responsive behavior as well as the biological activity were evaluated, suggesting that these smart bioactive composites are suitable to realize multifunctional dressings that sustain the local release of therapeutic adjuncts

RTM process monitoring and strain acquisition by fibre optics

Abstract The development of Resin Transfer Moulding technology for advanced applications requires a detailed analysis and control of the process. Fibres optics and Fibres Bragg Gratings are useful tools to investigate composite structures during their lifetime service. They are here employed for the monitoring of manufacturing phase and the acquisition of strains during product usage in service. The adopted monitoring procedure allows to follow all the stages of the production process, evidencing their possible influences over final laminate characteristics. Resin injection, curing and cooling, mould extraction, sensor position, deformation control during mechanical testing are analysed on the basis of the signal output from fibre optic sensors embedded in a model component

Implementation and Review of the Axisymmetric Equilibrium System of RFX-Mod2 within the MARTe2 Framework

A major refurbishment of the toroidal complex of the RFX-mod device is in progress and it will include the removal of the Inconel vacuum vessel and a modification of the stainless steel supporting structure to be made vacuum-tight. The axisymmetric equilibrium control in RFX-mod was responsible for the control of the plasma current, horizontal and vertical position along with its stability and the plasma shape. The new implementation framework, both hardware and software, is described. The system has been fully reviewed and modified, if needed, for its prospective use in RFX-mod2. In order to run tests in an operation-like context, the updated system has also been implemented in the MARTe2 framework, to be deployed for the real-time applications of RFX-mod2. The results of the previous versions were reproduced and the cycle-time requirements were met

numerical modelling of electromagnetic loads on fusion device structures

In magnetic confinement fusion devices, during abnormal operations (disruptions) the plasma begins to move rapidly towards the vessel wall in a vertical displacement event (VDE), producing plasma current asymmetries, vessel eddy currents and open field line halo currents, each of which can exert potentially damaging forces upon the vessel and in-vessel components. This paper presents a methodology to estimate electromagnetic loads, on three-dimensional conductive structures surrounding the plasma, which arise from the interaction of halo-currents associated to VDEs with a magnetic field of the order of some Tesla needed for plasma confinement. Lorentz forces, calculated by complementary formulations, are used as constraining loads in a linear static structural analysis carried out on a detailed model of the mechanical structures of a representative machine