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The paper targets on providing new experimental data for validation of the well-established mathematical models within the framework of the lattice Boltzmann method (LBM), which are applied to problems of casting processes in complex mould cavities.

An experimental campaign aiming at the free-surface flow within a system of narrow channels is designed and executed under well-controlled laboratory conditions. An in-house lattice Boltzmann solver is implemented. Its algorithm is described in detail and its performance is tested thoroughly using both the newly recorded experimental data and well-known analytical benchmark tests.

The benchmark tests prove the ability of the implemented algorithm to provide a reliable solution when the surface tension effects become dominant. The convergence of the implemented method is assessed. The two new experimentally studied problems are resolved well by simulations using a coarse computational grid.

A detailed set of original experimental data for validation of computational schemes for simulations of free-surface gravity-driven flow within a system of narrow channels is presented.

The purpose of this paper is to artificially construct a functional surface with self-propulsion flow characteristics for the directional transportation of propellant in surface tension tanks.

In this study, a method to enhance the propulsion efficiency by using functional surfaces of self-propulsion performance was proposed. Superhydrophilic wedged-groove with the superhydrophobic background was fabricated and the self-propulsion capacity was verified.

It is found that the self-propulsion capacity is related to the divergence angle of the wedged-groove in the hydrophilic area, and the velocity of the droplets on the deflector plate is the largest with the divergence angle of 4°; the temperature gradient field formed by the condensing device at the nozzle can accelerate the droplet outflow from the tank.

Realization of this idea provides an accurate control strategy for the complex flow process of propellant in plate surface tension tanks, which could enhance the efficiency of the tension tank significantly.

Prior research has highlighted the pervasive importance of digital technologies in business and societal settings, but their enabling role in digital transformation, and effective forms of organization to address tensions that arise during attempts to promote it, have been insufficiently explored. Therefore, the purpose of this paper is to investigate how and why tensions affect clusters established to foster digital transformation.

Empirical data were acquired through a qualitative exploratory holistic single case study, focused on the Swedish Cluster of Forest Technology. This included interviews with informants, selected by homogeneous purposive sampling, and event observation to investigate the personal perspectives of representatives of every company engaged in the cluster, followed by a thematic analysis of their comments.

The case study revealed three major tensions, between knowledge flow, collaboration and competition, but also others that were interrelated with those major tensions, related to matters such as trust and protection of intellectual property, power equality and hierarchy, and networks that must be managed in digital transformation efforts.

The paper extends understanding of the tensions that arise, and their management, in digital transformation processes.

This paper aims to present a requirements analysis for the processing of water-based electrode dispersions in inkjet printing.

A detailed examination of the components and the associated properties of the electrode dispersions has been carried out. The requirements of the printing process and the resulting performance characteristics of the electrode dispersions were analyzed in a top–down approach. The product and process side were compared, and the target specifications of the dispersion components were derived.

Target ranges have been identified for the main component properties, balancing the partly conflicting goals between the product and the process requirements.

The findings are expected to assist with the formulation of electrode dispersions as printing inks.

Little knowledge is available regarding the particular requirements arising from the systematic qualification of aqueous electrode dispersions for inkjet printing. This paper addresses these requirements, covering both product and process specifications.

The purpose of this paper is to explore interactional and procedural practices in managing tensions of coopetition (simultaneous collaboration and competition between firms).

Through an in-depth literature review of prior research within coopetition and strategy-as-practice fields, and by using two illustrative empirical examples, the authors develop a framework for preventing and managing coopetitive tensions through combinations of procedural and interactional practices.

The authors identify tensions related to strategizing, task and resource allocation, as well as knowledge sharing. Furthermore, they demonstrate potential ways of how these tensions can be prevented, resolved and managed.

The findings show that the analysis of tensions in coopetition would benefit from a holistic, multilevel approach that recognizes practices that are interactional (i.e. face-to-face interactions) as well as procedural (i.e. organizational routines). Coopetitive tensions and their resolution are related to the use or neglect of both types of practices. Furthermore, interactional and procedural practices are mutually interdependent and can complement each other in tension management in various ways.

The findings of this study shed light on the roles and activities of actual practitioners involved in coopetition, and shows how their work and practices in-use contribute to coopetition, related tensions and their resolution.

By adopting the strategy-as-practice approach, this study generates valuable insights into the practices and tensions in coopetition, as well as illuminates the roles of the practitioners involved in managing coopetition relationships.

This paper aims to print 3D structures from polymers that resist bacterial attachment by reactive jetting of acrylate monomers.

The first step towards printing was ink development. Inks were characterised to carry out an estimation of their potential printability using the Z parameter to predict stable jetting conditions. Printability conditions were optimised for each ink using a Dimatix DMP-2800, which enabled 3D structures to be fabricated.

UV photo-initiated polymers, which resist bacterial attachment, were found to be printable using piezo-based inkjet printers. The waveform required for each ink depends on the value of the Z parameter. Once the waveform and the printability parameters were optimised, 3D objects were fabricated.

This methodology has been confirmed as an effective method to 3D print materials that have been demonstrated to be bacteria resistant. However, ink curing depends on modification of some parameters (such as photoinitiator concentration or UV exposure time) which would result in an improvement of the curing process post jetting.

The combination of inkjet based 3D printing with new materials resistant to bacterial attachment means the possibility of building customised medical devices with a high level of complexity and bespoke features can be fully realised. The scope and variability of the devices produced will exceed what can be achieved using standard fabrication methodologies and can be applied to reduce the incidence of device associated infections and to address increased morbidity, mortality and health care costs associated with nosocomial infections.

In this paper, the novel use of materials that resist bacterial attachment has been described to build 3D structures using material jetting. Its value lies on the potential impact this methodology could produce in the biomedical device and research fields.

The purpose of this paper is to show that the droplet impact phenomenon is important for the advancement of industrial technologies in many fields such as spray cooling and ink jet printing. Droplet bouncing on the nonwetting surfaces is a special phenomenon in the impact process which has attracted lots of attention.

In this work, the authors fabricated two kinds of representative nonwetting surfaces including superhydrophobic surfaces (SHS) and a slippery liquid-infused porous surface (SLIPS) with advanced UV laser processing.

The droplet bouncing behavior on the two kinds of nonwetting surfaces were compared in the experiments. The results indicate that the increasing Weber number enlarges the maximum droplet spreading diameter and raises the droplet bounce height but has no effect on contact time.

In addition, the authors find that the topological SHS and SLIPS with the laser-processed microwedge groove array produce asymmetric droplet bouncing with opposite offset direction. Microdroplets can be continuously transported without any additional driving force on such a topological SLIPS. The promising method for manipulating droplets has potential applications for the droplet-based microfluidic platforms.

Managing supply chains (SCs) for sustainability often results in conflicting demands, which can be conceptualized as sustainability tensions. This paper studies sustainability tensions in electronics SC contexts and the related management responses by applying a paradox perspective.

A single case study on the electronics SC is conducted with companies and third-party organizations as embedded units of analysis, using semi-structured interviews that are triangulated with publicly available data.

The study identifies tension elements (learning, belonging, organizing and economic performing) conflicting with general social–ecological objectives in the electronics SC. The results indicate a hierarchal structure among the sustainability tensions in SC contexts. The management responses of contextualization and resolution are assigned to the identified tensions.

Framing social–ecological objectives with their conflicting elements as paradoxical tensions enables organizations and SCs to develop better strategies for responding to complex sustainability issues in SC contexts.

The study contributes toward filling the gap on paradoxical sustainability tensions in SCs. Empirical insights are gained from different actors in the electronics SC. The level of emergence and interconnectedness of sustainability tensions in a larger SC context is explored through an outside-in perspective.

The aim of the study is to deepen the knowledge about municipalities' risk communication for preparedness. This objective was pursued by analyzing how risk communication functions were organized in municipalities and by scrutinizing tensions in risk communication management.

The study relies on 19 qualitative, semi-structured interviews with communication practitioners in Swedish municipalities. The sample was purposive and included Swedish municipalities varying in number of inhabitants, geographical location, degree of urbanization, size and risk profile.

Risk communication is seen as a sub-field of crisis communication in municipalities' communication management. The task of initiating risk communication activities and campaigns is frequently assigned to the municipalities' safety units or emergency coordinators and is normally not part of communication practitioners' duties. Municipal communication practitioners often face challenges in trying to demonstrate the significance of the practitioners' role in risk communication and other risk-related activities within the municipality. The practitioners' work is characterized by four categories of tensions that are identified as follows: constitutional/legal, organizational, cultural and technological.

The identified tensions in risk communication are important for reflexive practitioners to consider, and the paper suggests three steps that municipal communication managers can take to handle them.

The study contributes with novel knowledge about municipal communication management in a context of risk communication. The study challenges the existing and dominant risk communication research and offers a more contextual and reflexive understanding of actual risk communication processes in municipalities.

This study aims to enhance merging of additive manufacturing (AM) techniques with powder injection molding (PIM). In this way, the prototypes could be 3D-printed and mass production implemented using PIM. Thus, the surface properties and mechanical performance of parts produced using powder/polymer binder feedstocks [material extrusion (MEX) and PIM] were investigated and compared with powder manufacturing based on direct metal laser sintering (DMLS).

PIM parts were manufactured from 17-4PH stainless steel PIM-quality powder and powder intended for powder bed fusion compounded with a recently developed environmentally benign binder. Rheological data obtained at the relevant temperatures were used to set up the process parameters of injection molding. The tensile and yield strengths as well as the strain at break were determined for PIM sintered parts and compared to those produced using MEX and DMLS. Surface properties were evaluated through a 3D scanner and analyzed with advanced statistical tools.

Advanced statistical analyses of the surface properties showed the proximity between the surfaces created via PIM and MEX. The tensile and yield strengths, as well as the strain at break, suggested that DMLS provides sintered samples with the highest strength and ductility; however, PIM parts made from environmentally benign feedstock may successfully compete with this manufacturing route.

This study addresses the issues connected to the merging of two environmentally efficient processing routes. The literature survey included has shown that there is so far no study comparing AM and PIM techniques systematically on the fixed part shape and dimensions using advanced statistical tools to derive the proximity of the investigated processing routes.