Nowadays, Digital Twin (DT) represents an emerging topic in Manufacturing and Logistics (M&L) systems due to its role as an enabler of digital transformation in the so-called Smart Factories. Since ...2017 it has been widely integrated into maintenance, production planning and control or layout planning decisions. Several frameworks and surveys have been proposed to provide guidelines, managerial insights, limitations and future research perspectives on this emerging topic. However, just a few works focus the attention on DT and its role in quantifying, evaluating and providing ergonomics, mental or physical workload, posture feedback or warnings to workers, aiming to improve their safety conditions. For this reason, this study investigates the current state of the art about the DT and its application as a tool to evaluate and integrate ergonomic aspects, or additional human factors, in M&L systems. Moreover, future research directions are provided.
The new Industry 5.0 paradigm complements the well-known Industry 4.0 approach by specifically driving research and innovation to facilitate the transition to sustainable, human-centric and resilient ...industry. In the manufacturing context, workers' diversity in terms of experience, productivity and physical capacity represents a significant challenge for companies, especially those characterized by high staff turnover and manual processes with high workload and poor ergonomics. In seeking to address such challenges, this research adopts a human-centric perspective to define new flexible job arrangements by developing a new multi-objective job rotation scheduling model. The proposed model is unique in that it aims to achieve multiple job assignment objectives by simultaneously considering different socio-technical factors: workers' experience, physical capacity and limitations, postural ergonomic risks, noise and vibration exposure, and workers' boredom. The model's implementation in real environments can be supported by new sensor-based technologies that collect data on workers' efficiency, ergonomic scores and task performance and enable workers to participate in measuring perceived fatigue and boredom. The primary goal of our model is to find the most appropriate assignment of job and individual-flexible rest-break plan for each worker. The authors test the model application in an industrial setting. Useful managerial insights emerge and prescriptive recommendations are provided.
•Flexible job scheduling and workforce organization in manufacturing and logistics systems according to I5.0 paradigms.•Job rotation scheduling model capable of integrating 3 different work aspects: productivity, ergonomics and workers' boredom.•We evaluate the impact of human factors and ergonomic criteria on system performance and workers' safety.•Managerial insights for the workforce job assignment considering individual worker characteristics and limitations.
Ergonomic aspects have a crucial role in manual assembly systems. They impact on the workers' health, final product quality and productivity. For these reasons, there is the necessity to integrate ...them into the assembly line balancing phase as, whereas, only time and cost variables are considered. In this study, human energy expenditures are considered as ergonomic aspects and we integrate them, for the first time, into the assembly line balancing problem type 2 through the rest allowance evaluation. We consider as an objective function the minimization of the smoothness index. Firstly, a new optimal method based on mixed integer linear programming and a new linearization methodology are proposed. Then, a heuristic approach is introduced. To complete the study, a computational experimentation is presented to validate the mathematical model and to compare the methodologies proposed in terms of computational time, complexity and solution. Additionally, we provide a detailed analysis of the impact that rest allowance evaluation can have on productivity comparing the results obtained, taking into account the rest allowance integration before, during and after the assembly balancing process.
The paper presents a systematic literature review on big size product manufacturing systems in MTO and ETO environments. In particular, the analysis is focused on highly customised, big and heavy ...products, calling for highly engineering solutions. This kind of products are characterised by low-volume demand, complex material bills, need of more than one worker in the same workstation (caused by the component dimensions and complexity), multi-skilled human resources and large floor space requirements. The analysis involved 587 research articles published from 1981 to 2017 from 118 international journals in the area of production research and operation management. Finally, 160 papers have been individuated and clustered in three main research topic area: specification processes and product design, production planning and control, project portfolio management. Results indicate that research focused on optimising and managing a large-size product manufacturing system is gaining growing attention in the last ten years. However, product/process design, production planning and control and project management techniques still lack innovations and ad hoc methods, capable to take into consideration both in-house part feeding problems, both ergonomics issues present in this kind of manufacturing environments.
Currently, the ageing population is getting higher attention in production systems due to the increasing percentage of the ageing workforce, which persists longer in the working environment. Older ...workers are more vulnerable because of a possible decrease in physical capacities but can have a higher experience level. It is important to evaluate these factors during production process decisions and adapt the working environment to such workers. In such a way, production systems performance and workers’ well-being are jointly achieved. In companies aiming to include these aspects, digitalisation and automation can provide tools that can be used at tactical, strategic or operational levels. For example, at the operational level, wearable sensors, smart devices or trackers can be used in analysing the working time, effort and physical fatigue of operators via human-energy expenditure. These measures can be used to assess the required recovery time. However, the most challenging step is to include these measures in the decision-making process to organise the working process for operators according to their profiles and health restrictions. In this paper, we show how fatigue can be incorporated into operational processes such as scheduling in the context of a Dual-Resource Constrained (DRC) job shop. We consider several models to integrate rest allowance into the scheduling process and present a heuristic approach to assign operations to workers and machines. The impact of rest allowance on system performance is measured and managerial insights are provided.
•We overview the impact of the presence of an ageing workforce in production with a focus on a DRC job shop. .•We study different models to integrate rest allowance in the scheduling process in DRC. .•We evaluate the impact of rest allowance on makespan.•We provide managerial insights for the fair inclusion of the ageing workforce in production.
E-commerce is always a more diffused sales channel around the whole world market. The grocery market has been interested in the expansion of this phenomenon, especially during the COVID-19 pandemic ...emergency, when electronic grocery (e-grocery) shopping increased considerably. Moreover, it has remained a diffused selling channel also later, in the non-emergency state. To satisfy this specific market demand, grocery chains are facing the need for a redesign with a new logistic perspective. A grocer can carry out online orders in several ways; it can process them directly in stores using internal staff to shop from the shelves during off-peak hours. Alternatively, some local stores can be closed to customers and dedicated to online orders (dark stores). Another strategy is to carry out online orders from a single distribution centre (e-hub), using stores to complete orders with very fresh products and from which to carry out deliveries. Finally, online orders can be wholly managed by multi e-hubs. Each solution has different logistics costs and performances, influenced by online demand.
For this reason, this work aims to present a cost-based function for grocery chains that compares four strategies to respond to e-grocery shopping. The cost function considers picking, refilling, and transport costs by varying orders and articles quantity. Further, we aim to minimise costs according to online order characteristics and volumes. We identify five decision variables to select the most suitable strategy for the design of the e-grocery network. Finally, a decision support system (DSS) is developed to define the best strategy based on the decision variables.
•We provide an overview of the main logistic strategies in grocery supply chains (SCs) to satisfy e-commerce demand.•We propose a cost function based on logistics costs including logistics hub, e-hub, store, and delivery costs.•We individuate the best strategy, according to the online volumes, customers characteristics, and orders characteristics.•We provide a user-friendly Decision Support System (DSS) for the definition of the best logistic strategy for e-grocery SCs.
The effects of workforce differences on manufacturing systems have attracted the attention of a wide range of researchers in recent years. The differences between workers in terms of skills, age, ...gender and anthropometric measures have a large impact on production system performance. In this study, the workforce differences factors in production system design and modelling were investigated, with the aim of understanding how the differences between workers could influence a production system and how they had been considered in previous studies. The papers selected from the Scopus database were categorised based on whether how human factors are incorporated into manufacturing system optimisation and design approaches is discussed therein or is not. To find relevant papers, two sets of keywords were defined: (1) keywords relating to the differences between workers and (2) keywords relating to the kind of problem under study. Furthermore, the investigated papers helped highlight the strengths and weaknesses of the existing literature and derive a discussion on the possible future research steps.
Healthcare supply chains (HSCs) have often been considered different from the usual supply chains (SCs) due to their high level of complexity, the presence of high-valuable medical materials and, ...finally, the fact that they deal with human lives. Furthermore, HSCs are not excluded from the increasing competitivity that is typical of the modern environment: International Healthcare systems are under increasing pressure to reduce waste and eliminate unnecessary costs while improving the quality and consistency of the care they provide to patient. The aim of this work is to analyse the impact of severe disruptions on SC performance in a Healthcare Supply Chain. More specifically, the objective of this study is to develop an approach to firstly analyse the effects of disruptions in terms of financial and operational performances, and successively to test different proactive and reactive mitigation strategies with the aim to maintain the highest service level, closed to 100%, in order to avoid shortages in hospitals’ wards. Disruptions can have a crucial impact on HSCs, because human lives can possibly be at the stake. Considering that the occurrence of disastrous events has been increasing in the last years, it is becoming inevitable to consider this risk in designing and planning HSCs that are more flexible and resilient. This work demonstrates that for long-lasting disruption, activating a backup supplier represents the most efficient mitigation strategy; on the other hand, for small-scale and short-duration disruptions, lateral transshipment represents a good way to mitigate the negative impacts of disruptions against a little increase in costs.
Ergonomics has a significant impact on productivity and human safety in manual assembly lines. For this reason, several studies in recent years have proposed including ergonomics in assembly lines. ...However, most works are focused on simple assembly lines, while only a few studies exist for mixed-model assembly lines (MMALs). Thus, in this paper, we propose a new methodological approach to include physical fatigue and rest allowance (RA) as ergonomic parameters in MMAL problems. For the balancing problem, we propose a linear mathematical model that minimises the cycle time by including RA. For the sequencing decision, we develop a heuristic approach that assigns workers to workstations according to the workers' age and their related maximum physical capacity. Then, we propose a linear sequencing model that minimises the work-overload by also evaluating RA to assign each worker according to her or his features. Finally, to complete the study, we test the mathematical models in a real case application and provide a detailed discussion of the results to highlight the benefits we can achieve with this approach.
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