An ensemble-learning model for failure rate prediction

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Sviluppo di metodologie di Lean Manufacturing per aziende X to Order

Nella produzione su commessa, in ambiente XTO con bassi volumi e alta variabilità, portare in tempo tutte le parti nel corretto punto di assemblaggio rappresenta la difficoltà principale. Perdite non programmate incrementano il lead time di produzione. Nelle aziende XTO, variazioni temporali dei vari codici rispetto alla pianificazione sfociano in perdita di sincronizzazione. A tale proposito viene revisionata la letteratura, sintetizzando e classificando alcuni articoli universitari. Vengono contestualizzate le realtà produttive evidenziando le maggiori criticità vissute e, in ultima battuta, mostrate le migliorie intraprese per correggerle. In questo lavoro vengono forniti alcuni spunti utili alle aziende che ritengono di dover riorganizzare e migliorare il proprio sistema logistico di gestione dei materiali destinati alle linee di assemblaggio Lo scopo è di studiare l'adattamento e l’evoluzione dei principi lean con l'obiettivo primario di convergere verso un nuovo insieme di principi che sono più chiaramente allineati per lo sviluppo lean in ambiente di produzione XTO

Development and implementation of Lean Manufacturing tools and methods for the manufacturing efficiency in Engineer-To-Order production environments

Traditionally, Lean manufacturing has been the focus of low-mix high-volume repetitive manufacturing industries. It must be noted that, in these industries, there are numerous researches illustrating success in the implementation of Lean manufacturing. In the last few years, in recognition of the success of the Lean manufacturing approach in the manufacturing sector, the amount of papers implementing Lean manufacturing outside the repetitive production environment, especially in Engineer-to-Order (ETO) manufacturing companies, has increased. However, while lean principles can be applied in any industry, in an ETO environment the implementation of methods and tools must be adapted. Only conceiving different new methods and tools it is possible to think to overcome one of the major constraints to unfold the full potential of Lean manufacturing in non-repetitive manufacturing environment. The research activities presented in this Thesis are inserted in this context. With the aim of extending the toolbox available to all practitioners in the ETO manufacturing companies, the research activity carried out focused on the development and implementation of Lean manufacturing tools and methods for the manufacturing efficiency in ETO production environments. This Thesis is concretized as follows. The first five chapters present research activities directly ascribable to ETO production environment. After exploiting the peculiarities of Manufacturing cost deployment (MCD), which is the fundamental pillar of World Class Manufacturing (WCM), the evaluation model has been extended to the ‘world’ of risk analysis and reliability, as well as to that of energy diagnosis in the process industry. Finally, other two chapters report additional research activities outstanding the Lean-ETO context. Still the interest in implementing Lean in non-repetitive manufacturing environment is growing, future work may be thus devoted to further extending the research here presented

Overall Construction Productivity: a new Lean Metric to identify construction losses and analyse their causes in Engineer-to-Order Construction Supply Chains

Construction projects are often unique, time-limited and require a high degree of customization by involving a significant number of Engineer-to-Order (ETO) components. Usually, ETO construction supply chains are composed by a fabrication part off-site and the installation part on-site where different supply chains have to be merged. Generally, many problems are identified during construction on-site and often in a late phase when recovering actions cannot be applied anymore. As a result, construction projects frequently face delays and budget overruns. Owing to these considerations, the paper proposes (i) a framework able to identify the losses and causes of ETO construction supply chains and (ii) a novel metric named Overall Construction Productivity (OCP) supporting the quantification of the overall impact of losses and the implementation of improvement actions. The proposed framework and metric were applied and validated in a medium-sized ETO façade supplier company and a hospital construction project

Overall Task Effectiveness: a new lean performance indicator in engineer-to-order environment

Purpose -The purpose of this paper is to propose a new lean metric named Overall Task Effectiveness (OTE), which can help analyst (i) to define target task times, and(ii) to identify the hidden losses that account for most of the recorded time of manual assembly activities. Design/methodology/approach – An alternative losses classification structure is developed to divide the losses that are external to the project order, and the losses due to inefficiencies directly ascribable to the project order. Starting from this classification structure of the losses,a novel lean metric, inspired from the well-known OEE,is developed to evaluate the effectiveness of a manual assembly task.A case study is provided, that briefly explains the methodology and illustrates the capability of the corresponding metric. Findings – This toolrepresents a suitable method to achieve simultaneously the dual purpose (i) to establish time standards, and (ii) to identify the hidden losses that account for most of the recorded time of a manual assembly activities, estimating the impacts of potential corrective actions in terms of both efficiency and effectiveness. Practical implications – OTE provides practitioners with an operative tool useful to highlight the points where the major inefficiencies take place in industries producing large complex items via manual assembly lines. Its practical application is fully demonstrated using a case study concerning a manufacturer of train wagons. Originality/value – One distinctive, and contemporarily appealing, feature of OTE with respect to other analogous KPIs is that it provides a breakdown structure for process losses that simplifies the task of evaluating the current performances and, at the same time, individuates both the source of losses and the corresponding corrective actions

Rolling Kanban: a new visual tool to schedule family batch manufacturing processes with kanban

Rolling Kanban is the name of a kanban management methodology for batch processes manufacturing environment. Proposed in the early 2000s by FESTO Consulting, for two decades we have lost knowledge both from operative and scientific point of view. Basically, Rolling Kanban means a visual planning methodology based on the production of product-families and variants where: (i) set-up times are reduced between the products of the same family, and (ii) relevant times (dozens of minutes if not even hours) must be considered for changeover between products of different families. In addition, the cyclic production sequence between different product families cannot be maintained. Considering that very few technical information and documents are available about this approach, the main objective of this paper is to retrieve and present, for the first time to the scientific community, the Rolling Kanban methodology. Besides, a real industrial implementation concerning a manufacturer of domestic fittings is discussed as a case study. More specifically, two novel versions of the original Rolling Kanban technique are fully presented to effectively overcome certain limits and criticalities found during its operative use, such as the difficulty to realize a pull production, considering increased set-up time for changeover between products of different families

The Impact of COVID-19 on the Italian Footwear Supply Chain of Small and Medium-Sizes Enterprises (SMEs) - Evaluation of Two Case Studies

This paper aims to provide a case study related to two small and medium-sized enterprises (SMEs) of the Italian footwear supply chain, comparing sales and production data from pre-pandemic years with those affected by the COVID-19 (SARS-CoV-2) pandemic. Specifically, two Tuscany companies in the world of fashion footwear sector have been assisted in the analysis of their supply chains. In particular, the case research method has been employed for theory building to evaluate how companies reacted to the disruption caused by the COVID-19 pandemic to focus on potential resilience strategies that could be adopted to deal with a disruption, such as that caused by the COVID-19 pandemic. Specifically, in order to understand the dynamics of the supply chains, the standard production processes were initially studied and mapped, analyzing in detail the planning, programming, and control phase. After conducting a descriptive analysis of the data, possible resilience factors of SMEs’ fashion supply chains have been extracted, and strategies that SMEs could adopt to better cope with the disruption caused by the pandemic have been suggested. The outcomes of this study can be used by decision-makers to predict the operative and long-term impacts of epidemic outbreaks on the supply chains with some suggestions of potential resilience improvement strategies. The paper is concluded by summarizing the most important insights and outlining future research agenda

COBACABANA: a real industrial application in a job shop system

COntrol of BAlance by CArd-BAsed NAvigation (COBACABANA) is a card-based system for job shop control. This paper presents a real industrial application of COBACABANA aimed at solving production control problems in an Italian manufacturer of valves and flanges, configured as a job shop system. To the best of our knowledge, this is the first industrial implementation of COBACABANA. Although COBACABANA can be extended to estimating delivery time allowances, this research focuses only on its shop floor control mechanism. In the case study, the COBACABANA boards and cards are carefully reviewed. The criticalities and limitations of traditional COBACABANA are fully explored and, subsequently, two new boards and a new form are introduced to facilitate its practicality and ease of implementation. The new tools enable planners to better monitor the pre-shop pool status and the progress of orders

Risk Failure Deployment: a novel integrated tool to prioritize corrective actions in failure mode and effects analysis

In this paper, a novel integrated tool for failure mode and effects analysis (FMEA), opportunely named Risk Failure Deployment (RFD), which is able to evaluate the most critical failure modes and provide analyst with a practical and step‐by‐step guidance by selecting the most effective corrective actions for removal/mitigation process of root causes, is presented. Thanks to the modification of the framework of the Manufacturing cost deployment (MCD) and to its well‐structured use of matrices, the novel RFD is able both to handle the dependencies and interactions between different and numerous failures and to evaluate the most critical ones on the basis of the risk priority number (RPN). Thereafter, the logical relationship between root causes and failure modes is assessed. Successively, the prioritization of corrective actions that are the most suitable for root causes is executed using not only the RPN but also other criteria, such as the economic aspect and the ease of implementation, that are unavoidable to execute a rational and effective selection of improvement activities. The effectiveness and usefulness in practice of the original tool for the prioritization of corrective actions to mitigate the risks due to failure modes collected during FMEA are presented in a case study

Lean manufacturing tool in Engineer-To-Order environment: Project Cost Deployment

The present paper proposes a modified version of the Manufacturing cost deployment (MCD) method to analyse engineer-toorder (ETO) production systems. The novel approach, named Project cost deployment (PCD), introduces two substantial and innovative modifications. To begin with, the concept of manual assembly macro-activity replaces the traditional concept of station. Then, a brand-new structure for classifying and analysing losses is introduced, that is specifically defined to deal with the inefficiencies of the manual assembly tasks. The validity of the approach is proved by a real-world industrial application. The obtained results demonstrate that the PCD method allows the analyst to identify the hidden losses and to quantify the wastes from an economical point of view. In addition, PCD permits to estimate the impacts of potential (lean) improvement activities and projects in terms of both efficiency and effectiveness