An RFID application for the process mapping automation

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A decentralized application for the traceability process in the pharma industry

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Dynamic failure rate model of an electric motor comparing the Military Standard and Svenska Kullagerfabriken (SKF) methods

Abstract Electric motors are industrial systems' components widely diffused enabling all productive processes and safety equipment. They are affected by aging effect with a contribution based on the environmental condition on which they work. In order to design efficient maintenance plans, the behaviour of their main components, such as bearings and winding, has to be predicted. Therefore, a model-based methodology is applied aiming at codifying the failure rate of an electric engine, taking into account the thermal aging and relevant environment boundary conditions in which bearings and winding operate. The winding failure mode is coded by means of the Military standard technique while the bearings one is simulated comparing the Military Standard and the Svenska Kullagerfabriken (SKF) techniques. While the former predicts more conservative behaviours, the latter, taking into account lubrication conditions, dynamic loads and a better knowledge of materials quality, enables to capture the evolution of the operative conditions. The proposed reliability model can capture both the deterministic and stochastic behaviour of the electric motor: it belongs to the field of hybrid automaton application; the model is coded by means of the emerging software framework called SHYFTOO. The proposed model and the Monte Carlo simulation process that performs its evolution can support the development of a new class of electric motors: a cyber-physical oriented electric motor

Economic order quantity and storage assignment policies

The basic Harris’s lot size model dates back to 1913 (Harris, 1913), hence one century from its publication has been recently celebrated. Starting from the seminal work of Harris, a wide plethora of contributors has faced with the lot-sizing problem for fitting the basic model of the economic order quantity to several environments. In fact, the three key parameters constituting the basic model, i.e. the demand rate, the ordering costs, and the inventory holding costs, have been widely explored in order to relax the assumptions of the original model. However, to the best of the authors’ knowledge, the liaison between holding costs and warehouse management has not been completely addressed. The holding costs have been early considered for simplicity as primarily given by the cost of capital, and thus dependent solely on the average inventory on stock. Conversely, by including a more detailed supply chain costs contribution, the economic order quantity calculus appears depending on a recursive calculus process and on the storage assignment policy. In fact, different approaches of warehouse management, e.g. shared and dedicated storage, lead to highly variable distances to be covered for performing the missions. This leads to a total cost function, and consequently to optimum lot sizes, that are affected by the warehouse management. In this paper, this relationship has been made explicit in order to evaluate an optimal order quantity taking into account storage assignment policies

Performance assessment of domestic photovoltaic power plant with a storage system

Grid-connected low voltage photovoltaic power plants cover the majority of the power capacity installed in Italy. They offer an important contribution to the power demand of the utilities connected but, due to the nature of the solar resource, the night time consumption can be satisfied only withdrawing the energy by the national grid, at the price of the energy distributor. Thanks to the improvement of storage technologies and the decreasing of costs, the installation of a system of battery looks a promising solution. In this paper, a model-based approach to analyze and discuss the performance of a domestic photovoltaic power plant with a storage system is presented

Designing an Optimal Shape Warehouse

Part V: Product and Asset Lifecycle ManagementInternational audienceThe paper addresses the topic of designing the shape of a warehouse and shows a comparison between a standard storage-handling system, which is designed taking into account the minimization of the handling planar path, and the one which is designed trying to minimizing the overall handling energy consumption. This comparison leads to a discussion on the opportunities which result from the construction of a shallow warehouse in term of building construction costs, layout management and storage surface efficiency. This paper is the first step in the analysis of a more comprehensive research about the life cycle assessment of a warehouse, the manpower utilization and the balanced equilibrium between handling energy requirement and performances of most used handling systems

Failure Prevention Through Performance Evaluation of Reliability Components in Working Condition

The reliability of a system during operation can be expressed quantitatively through different time functions. Mathematical procedures and statistical laws allow to assess the precise analytical relations between these functions. Referring to a generic system or component is a common experience that its duration in-service is not predictable in a deterministic way. This consideration identifies the lifetime (or time to failure) of the component as a continuous random variable, susceptible to a statistical description, whose estimate is crucial in the design phase, or in any case before the commissioning of equipment. In a second stage, the actual values of reliability must be compared with the forecast values arising from the theoretical statistical model used. This comparison allows assessment of the goodness-of-fit level and the confidence level of the prediction model, in order to validate it for any future equipment redesigns or for similar equipment. In this context, the present work is aimed at identifying the most appropriate statistical tools for the comparison above, and then to assess the reliability of the forecast data, compared to the real performance of a reliability system. For this purpose, a literature analysis was conducted, with a dual purpose: The identification of statistical models most commonly used to describe the reliability function of a system; to provide a choice of appropriate indicators and effective tests for assessing the confidence of the statistical models for reliability scopes. The models identified were then applied, as an example, to the real case of a catalytic cracking catalyst with the fluidized bed of a petrochemical plant. The results obtained from the case study, discussed in the final section of the work, offer many points of comparison between the various statistical models as well as a first overview of their reliability

Influence of AHP Methodology and Human Behaviour on e-Scouting Process

Part 3: StrategyInternational audienceThe e-scouting process, to search for and select products whose characteristics are known in catalogues, is often inefficient and ineffective: the overload of information available on the Web and the human limitations in processing information, are the main cause. Experiments, in order to simulate the e-scouting process of a leverage [1] product by a set of student buyers, were performed and results on effectiveness and efficiency of e-scouting process strategies and methods are collected and analyzed. Referring to the strategic evaluation of the e-scouting process, results show that a Decision Support System (DSS) based on Analytic Hierarchy Process (AHP) methodology [2], supports the buyer- Human Decision Maker (HDM) to interpret in a coherent way the strategic guidelines previously set by the high level management. Regarding to method’s evaluation of e-scouting process, was appreciated that if quantitative product features are known and limited in a range of variation, the Human Decision Maker’s evaluation substantially coincide with the evaluation of a Virtual Decision Maker (VDM) based on Analytic Hierarchy Process. On the contrary, the difference among HDM and VDM is considerable when quantitative product characteristics are unknown or unlimited. The work carried out has shown that using a DSS based on AHP is always useful to improve efficiency and effectiveness on e-scouting process’ strategies however efficiency and effectiveness on e-scouting process’ method can be improved by DSS based on AHP only if the human evaluation about product features is limited

SHyFTA, a Stochastic Hybrid Fault Tree Automaton for the modelling and simulation of Dynamic Reliability problem

Reliability assessment of industrial processes is traditionally performed with RAMS techniques. Such tech-niques are static in nature because they are unable to consider the multi-state operational and failure natureof systems and the dynamic variations of the environment in which they operate.Stochastic Hybrid Automaton appears to overcome this weakness coupling a deterministic and a stochas-tic process and integrating the features of a dynamic system with the concepts of dynamic reliability.At the state of the art, no attempts to enhance a formal RAMS technique with dynamic reliability has beentried, nor a computer-aided tool that plays as expert system has been coded yet.The aim of this paper is to fill this gap with a simulation formalism and a modelling tool able to combinethe Dynamic Fault Tree technique and the Stochastic Hybrid Automaton within the Simulink environment.To this aim the MatCarloRE toolbox was adapted to interact with a Simulink dynamic system. The resultingassembly represents an important step ahead for the delivering of a user-friendly computer-aided tool for thedynamic reliability