An Iterative Design Method from Products to Product Service Systems—Combining Acceptability and Sustainability for Manufacturing SMEs

Manufacturing small- and medium-sized enterprises (SMEs) play a crucial role in the economic development and resource consumption of most regions. Conceptually, a product-service system (PSS) can be an effective way to improve the sustainability of manufacturing SMEs. However, the construction of PSSs requires enterprises to integrate a large number of product and service resources. Moreover, current PSS design methods mostly construct a new set of highly service-oriented PSS solutions based on customer needs while seldom considering the combination of acceptability and sustainability for manufacturing SMEs at the initial stage of design, which may lead to the difficulties in applying PSS solutions beyond enterprise integration capacity or result in the waste of existing product resources. Instead of constructing a new PSS solution, this paper proposes the treatment of existing product modules as the original system. The PSS solution is iteratively constructed with the upgrade of the original system in a gradual way, which is driven by systematic performance (this process can be suspended and repeated). Phased iterative design solutions can be applied by manufacturing SMEs according to their development needs. The analytic hierarchy process (AHP), Lean Design-for-X (LDfX), design structure matrix (DSM), and Pearson correlation coefficient (PCC) are combined in an iterative design process from customer needs and system performances to PSS solutions. The feasibility of the proposed method is verified through the iterative design case from electric pallet trucks to warehousing systems. It is proved that this method is more sustainable and easier to be accepted by manufacturing SMEs than existing PSS design methods through in-depth interviews with entrepreneurs.

Optical metasurfaces towards multifunctionality and tunability

Optical metasurfaces is a rapidly developing research field driven by its exceptional applications for creating easy-to-integrate ultrathin planar optical devices. The tight confinement of the local electromagnetic fields in resonant photonic nanostructures can boost many optical effects and offer novel opportunities for the nanoscale control of light–matter interactions. However, once the structure-only metasurfaces are fabricated, their functions will be fixed, which limits it to make breakthroughs in practical applications. Recently, persistent efforts have led to functional multiplexing. Besides, dynamic light manipulation based on metasurfaces has been demonstrated, providing a footing ground for arbitrary light control in full space-time dimensions. Here, we review the latest research progress in multifunctional and tunable metasurfaces. Firstly, we introduce the evolution of metasurfaces and then present the concepts, the basic principles, and the design methods of multifunctional metasurface. Then with more details, we discuss how to realize metasurfaces with both multifunctionality and tunability. Finally, we also foresee various future research directions and applications of metasurfaces including innovative design methods, new material platforms, and tunable metasurfaces based metadevices.

High-cycle fatigue tests of pretensioned concrete beams

Pretensioned concrete beams are widely used as bridge girders for simply supported bridges. Understanding the fatigue behavior of such beams is very important for design and construction to prevent fatigue failure. The fatigue behavior of pretensioned concrete beams is mainly influenced by the fatigue of the prestressing strands. The evaluation of previous test results from the literature indicated a reduced fatigue life in the long-life region compared with current design methods and specifications. Therefore, nine additional high-cycle fatigue tests were conducted on pretensioned concrete beams with strand stress ranges of about 100 MPa (14.5 ksi). The test results confirmed that current design methods and specifications overestimate the fatigue life of embedded strands in pretensioned concrete beams.

Using the Behaviour Change Wheel to Design an App to Change Tourist Behaviour and Increase Dispersal into Regional Areas

Currently, many tourism destinations are experiencing greatly reduced tourism due to COVID-19. In order to ensure that regions that wish to engage in tourism can share the benefits of it more equally, and to prevent the predicted future problem of overuse of popular areas once pre-COVID visitor numbers resume, an app to encourage tourists and leisure-seekers to change their behaviour and disperse into regional areas has been developed. The Behaviour Change Wheel was used to define the problem, find suitable intervention functions and design methods of delivery that could increase tourists’ capability, opportunity and motivation to disperse farther into regions. The Huon Valley of Tasmania, Australia, was used as a research area. Our application of the Behaviour Change Wheel methodology determined that active engagement in logistic, value-based, and social information has the greatest chance of changing behaviour in this region and a list of Behaviour Change Techniques has been developed and considered in the design of a gamified travel app.

Industry Survey on the Current State of Stope Design Methods in the Underground Mining Sector

Stope design is a core discipline within mining engineering. This study analyzes the current state-of-the-art of stope design through a survey addressed to mining industry professionals. In stope design research the dominance of empirical methods has slowly shifted towards numerical methods. Recent advancements have mostly focused on the development of stope optimization algorithms. The survey consisted of 19 questions and was distributed to stope design experts via email, LinkedIn messages, and the Mining Industry Professionals network forum. In total, 36 responses of satisfying quality from 20 countries were received and analyzed. No dominance of a single stope design method was recognized. Empirical methods and personal expertise are still used widely. However, a readiness for change in stope design practice was indicated in 87% of responses. The current needs of the stoping-based underground mining sector are to increase the amount of geotechnical data, automate stope design and implement related software, and integrate these into general mine planning. According to 70% of the participants, acquired geotechnical data should be available within three days to be employed in design practice. The industry is ready to implement more efficient stope design methods if they offer results proven in case studies.