The impact of Additive Manufacturing on Supply Chain design: a simulation study

Additive Manufacturing is a production technology, which completely differs from the traditional subtractive approach. Because its different nature, its application could cause strong changes in supply chains and it could affect the relationship between the supply chain players. This paper proposes a quantitative evaluation of the Additive Manufacturing effects on the supply chain performance, considering different system configurations. A simulation model has been implemented in order to reproduce the behavior of the players and compare different scenarios. Both additive and traditional technologies have been modelled in order to compare their efficiency. Moreover, different supply chain configurations have been tested to assess the additive production feasibility combined with different supply chain structures. Results confirm that Additive Manufacturing provides good improvements in supply chain performances offering significant benefits in the decentralized solution

Economic and Environmental Sustainability for Aircrafts Service Life

Aircrafts are responsible for a significant environmental impact mainly due to the air pollution caused by their motors. The use of composite materials for their production is a way to significantly reduce the weight of the structures and to maximise the ratio between the payload weight and the gasoline consumption. Moreover, the design phase has to consider the cost of different operations performed during the aircraft service life. During the entire life cycle, one of the main costs is the maintenance one. In the current literature, there is a lack of knowledge of methods for maintenance cost estimation in the aircraft industry; moreover, very few environmental assessment methods have been developed. Thus, the aim of this paper is to define a new method to support the aircraft design process; both the environmental and the economic dimensions have been included with the purpose of assessing the aircraft sustainability during its service life. A green index has been identified mixing the maintenance cost and an environmental parameter with the aim of identifying the greenest solution. A final practical application shows the feasibility and the simple application of the proposed approach

Assessing Risks Awareness in Operating Rooms among Post-Graduate Students: A Pilot Study

Background: In this study, we promote a global approach to occupational risk perception in order to improve occupational health and safety training programs. The study investigates the occupational risk perception of operating room healthcare workers using an Analytic Hierarchy Process approach. Methods: A pilot study was carried out through a cross-sectional survey in a university hospital in Southern Italy. An ad hoc questionnaire was administered to enrolled medical post-graduate students working in the operating room. Results: Fifty medical specialists from seven fields (anaesthetists, digestive system surgeons, general surgeons, maxillofacial surgeons, thoracic surgeons, urologists, and gynaecologists) were questioned about perceived occupational risk by themselves. Biological, ionizing radiation, and chemical risks were the most commonly perceived in order of priority (w = 0.300, 0.219, 0.210). Concerning the biological risk, gynaecologists unexpected perceived this risk as less critical (w = 0.2820) than anaesthesiologists (w = 0.3354), which have the lowest perception of the risk of ionizing radiation (w = 0.1657). Conclusions: Prioritization methods could improve risk perception in healthcare settings and help detect training needs and perform sustainable training programs

Simulation Techniques Prioritization For The Additive Manufacturing Integration In Traditional Production Contexts

Additive Manufacturing (AM) is a modern manufacturing approach and it is considered one of the key enabling technologies of Industry 4.0 paradigm. The attractive feature of this technology concerns, mainly, the possibility to build geometrically complex parts in a single step avoiding all the stages of a traditional manufacturing process and, therefore, reducing the production lead time. Originally, this technology was intended for the rapid prototyping. Nowadays the integration of AM in the Traditional Practical Context (TPC) continues to expand and it is emerging as a valid alternative for the production of low size batches that consist of customized products. This work points out the open issues about the spread of AM technologies, especially, in the production of metal parts. Simulation is a strategic method to evaluate the changes caused by the inclusion of this disruptive technology in a conventional shop floor. The Analytic Hierarchy Process (AHP) is used as decision making approach to prioritize the simulation techniques

Complexity-driven product design: part 1—methodological framework and geometrical complexity index

Modern industries are experiencing radical changes due to the introduction of high technological innovations. In this context, even more highly complex and customized products are required, increasing the need of tending towards the concept of complexity for free. In addition, new products are conceived with the circular economy in mind, considering possible multi life-cycle at the early design stage to reduce time and costs while ensuring high quality standards. To evaluate the overall product complexity, this research combines geometrical, manufacturing, assembly, and disassembly complexity features, typically treated separately in the literature. The research is divided into two parts and proposes a novel methodological framework for assessing product complexity with an overall view, integrating many aspects of product life cycle. The framework aims to create a rank of product configurations, on the base of complexity. Making complexity assessment procedures objective is essential to effectively support decision-making processes, especially when introducing advanced manufacturing technologies such as Additive Manufacturing (AM). Additionally, it is necessary to know the complexity of the individual components before the overall assembly. This paper deals with the first part of the research, proposing the aforementioned novel methodological framework, with a great focus on geometrical complexity. A geometrical complexity index is defined through experimental and numerical surveys, involving CAD modeling experts and considering numerous metrics found in the technical literature. The proposed methodological framework and the geometrical complexity metric can provide useful tools for businesses looking to evaluate their product complexity and identify areas for improvement

Technology selection in green supply chains - the effects of additive and traditional manufacturing

In recent years, the concept of sustainability is emerging as one of the main concerns in modern society. In this context, industrial production processes are changing thanks to the development of green strategies. The selection of a new production solution is a crucial strategic decision and the introduction of new technologies could cause deep changes to the entire supply chain configuration. This paper introduces a new approach designed to understand the importance of supply chain considerations for a suitable technology assessment. It is aimed at proposing a quantitative model for the evaluation of different structure of supply chains based on different production technologies. In particular, by defining a set of Key Performance Indicators and applying a multi-criteria decision method, a final score is computed, giving important information about both environmental and economic aspects. A numerical example regarding the comparison between Additive and Traditional Manufacturing processes is presented in order to demonstrate the applicability and the effectiveness of the proposed method. Results show that additive solutions bring evident reduction in Carbon Emission and better supply chain and logistics performance. Anyway, production volume strongly influences the economic results and the competitiveness of additive manufacturing remains limited when compared to the traditional manufacturing. (C) 2020 Elsevier Ltd. All rights reserved

Ergonomic Assessment Methods Enhanced by IoT and Simulation Tools

The advent of Industry 4.0 (I4.0) principles and technologies has been a great boost for manufacturing companies, constantly focused on the production processes optimization in order to reach the double objective of improving productivity and minimizing related costs. Today, the use of I4.0 technologies seems to be more accessible for a large number of companies, allowing to perform a more detailed analysis on their processes by means of experimental data coming directly from the system. In this context, ergonomics, which has been underestimated until 30 years ago, is assuming more and more importance. This paper aims at proposing a methodology focused on an ergonomic analysis carried out by implementing data collected from the field; in particular, a set of inertial sensors integrated in the worker suit detects the body posture. Then, thanks to the Industrial Internet of Things (IIoT), data are transferred to a simulation software in order to quickly evaluate the current ergonomic effort. In this way, it is possible to perform a real-time evaluation on the workstation design and consider a possible re-design with the aim of improving ergonomics

Aircraft Maintenance: Structural Health Monitoring Influence on Costs and Practices

The structural health monitoring (SHM) represents an evolution of the traditional way to design and maintain mechanical structures. SHM systems allow to continuously (or discretely) monitor the structural integrity of an asset, not waiting for the planned check. This result implies an important reduction of inspection time and guarantees an improvement of service life cost of the structural components, but how and how much this cost can be influenced is still an open issue. This research addresses the identification of previous studies that dealt with this topic. A systematic literature review (SLR) is carried out with the aim of investigating the current SHM state-of-the art in the aircraft industry in order to point out the main advantages deriving from the application of these technologies and the existing gaps and limitations. Three database (Scopus, Web of science and Google Scholar) are used for selecting peer-reviewed papers that address with evidence the changes in maintenance practices resulting from the use of SHM. The analysis proves the differences between the traditional programmed maintenance and the innovative predictive approach based on SHM information in terms of interval inspection policy and costs. Moreover, the technical limits that do not allow to totally exploit the potential strength of SHM are outlined

Structural analysis of styrene oxide/haemoglobin adducts by mass spectrometry: identification of suitable biomarkers for human exposure evaluation

The structural characterisation of adducts formed by the in vitro reaction of haemoglobin (Hb) with styrene oxide (SO), the most reactive metabolite of the industrial reagent styrene, was obtained by liquid chromatography/electrospray ionisation mass spectrometry (LC/ES-MS) analysis of modified tryptic peptides of human Hb chains. The reactive sites of human Hb towards SO were identified through characterisation of alkylated tryptic peptides by matrix-assisted laser desorption/ionisation with tandem mass spectrometry (MALDI-MS/MS). A procedure was set up based on this characterisation, allowing Hb modification to be assessed by monitoring SO/Hb adducts using HPLC with selected ion recording (SIR) mass spectrometry. By this methodology it was also possible to compare advantages and disadvantages of presently available strategies for the measurement of Hb adducts with SO. The results obtained could most plausibly lead to the optimisation of molecular dosimetry of SO adducts, and the analytical procedure described herein could be applied to the biological monitoring of styrene exposure in the workplace

Product And Process Integrated Design To Enhance Smart Manufacturing Systems

During recent years, industrial world faced transformations that led companies to introduce the concepts and the technologies of a new industrial paradigm, named Industry 4.0 (I4.0), in order to improve their products and their production processes. In the context of I4.0, factories are becoming smart, more flexible and collaborative, satisfying the current demands of increasingly competitive markets and of products closer to the real needs of customers. Within this framework, the approach to product and process design is changing too, supported by the use of complex numerical analyses for testing and validating the performance of both products and production processes. This is made possible thanks to the Digital Manufacturing (DM) approach, that allows to reduce the design times and to validate the design solution in virtual environments, without setting up detailed and expensive experimental sessions. This paper aims to propose a possible methodological framework to better carry out the design of new products and production systems, according to the DM principles