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A rapid prototyping process applying ceramic gelcasting and assembly mould shape deposition manufacturing has been developed to fabricate mesoscale silicon nitride components with complex 3D geometry. An overview of the fabrication of Si₃N₄ burner arrays for gas turbine reheat applications is demonstrated. The design of burner arrays features internal fuel passages and integrated fuel injection elements, which cannot be manufactured by conventional methods. Geometrical decomposition of design models and recent developments in ceramic processing provide a novel approach in prototyping the burner arrays. In this paper, issues of materials compatibility, mould fabrication strategies, ceramic processing, and design iterations will be discussed along with the functional test of the 4×4 burner array.

Social media have become an increasingly important venue for prosocial campaigns. Competing for the public’s attention in the digital space is an ongoing challenge. This study aims to test the influence of ad-context congruence, ad position and ad type (i.e. public service advertising [PSA] vs cause-related brand [CRB] advertising) on the effectiveness of prosocial native advertising on social media.

Two experiments were conducted on different social media platforms (i.e. Twitter and Instagram) with varied prosocial issues (i.e. healthy eating and environmental sustainability).

Experiment 1 indicated that the congruence between prosocial native ads and social media feeds elicited greater ad involvement and a more favorable ad attitude, regardless of ad position. Experiment 2 revealed that such an impact was contingent on whether the prosocial native ad was a public service ad or a CRB ad. The positive influence of ad-context congruence was pronounced among public service ads but was not observed among CRB ads. Perceived ad involvement mediated the interaction effects between ad-context congruence and ad type on ad attitude and behavioral intention.

The study extends ad-context congruence research to the context of prosocial native advertising on social media. Moreover, it identifies ad type as a boundary condition for the congruence effects and reveals that increased ad involvement is the mechanism underlying the positive effect of congruent PSA.

This study aims to provide an overview of rapid prototyping (RP) and shows the potential of this technology in the field of medicine as reported in various journals and proceedings. This review article also reports three case studies from open literature where RP and associated technology have been successfully implemented in the medical field.

Key publications from the past two decades have been reviewed.

This study concludes that use of RP-built medical model facilitates the three-dimensional visualization of anatomical part, improves the quality of preoperative planning and assists in the selection of optimal surgical approach and prosthetic implants. Additionally, this technology makes the previously manual operations much faster, accurate and cheaper. The outcome based on literature review and three case studies strongly suggests that RP technology might become part of a standard protocol in the medical sector in the near future.

The article is beneficial to study the influence of RP and associated technology in the field of medicine.

Organizational justice research traditionally focuses on individuals’ reactions to how they are treated by others. However, little attention has been given to why individuals choose to behave fairly or unfairly in the first place. Our chapter draws on the literature in ethical decision making (Rest, 1986) to identify five distinct factors that influence an individual's decision to treat others fairly. Using this model as a foundation, and drawing on extant research in justice, we explore five different types of roadblocks to fair behavior. We explore the implications of these roadblocks for organizations concerned with creating and maintaining a fair workplace. Finally, we discuss future research suggested by the five factors and some dilemmas, issues, and caveats relevant to the proposed model.

The purpose of this research is to develop a building information modelling (BIM)-enabled sustainable design process model that identifies critical decisions actions in the design process along with the information and level of detail that facilitate an informed and timely decision. Building performance analysis is usually performed after the design and construction documents are produced, resulting in lost opportunities.

A number of research methods have been adopted; these include extensive literature review and 11 in-depth exploratory interviews with industry practitioners (sustainable building design experts, early BIM adopters).

Project delivery methods have a significant effect on the sustainable outcome of buildings. The development of a structured process can assist sustainable design practice among building professionals. Learning from implemented projects, that have utilised BIM processes, facilitates the scope of creating this process and advises future projects to prevent failures. Process mapping is essential to streamline the process, support key project processes and help the design team manage their own responsibilities and deliverables required by them.

The identification of the gap and the need for a structured process for sustainable building design for BIM execution is discussed. The synergies that exist between BIM, building performance modelling, Building Research Establishment’s Environmental Assessment Method assessment and the Royal Institute of British Architects Plan of Work are shown. The effect that project delivery has on sustainable design outcome has been established. A coordinated collaborative design process model is presented based on the findings from interviewing early adopters.

The purpose of this study is, to compare laser-based additive manufacturing and subtractive methods. Laser-based manufacturing is a widely used, noncontact, advanced manufacturing technique, which can be applied to a very wide range of materials, with particular emphasis on metals. In this paper, the governing principles of both laser-based subtractive of metals (LB-SM) and laser-based powder bed fusion (LB-PBF) of metallic materials are discussed and evaluated in terms of performance and capabilities. Using the principles of both laser-based methods, some new potential hybrid additive manufacturing options are discussed.

Production characteristics, such as surface quality, dimensional accuracy, material range, mechanical properties and applications, are reviewed and discussed. The process parameters for both LB-PBF and LB-SM were identified, and different factors that caused defects in both processes are explored. Advantages, disadvantages and limitations are explained and analyzed to shed light on the process selection for both additive and subtractive processes.

The performance of subtractive and additive processes is highly related to the material properties, such as diffusivity, reflectivity, thermal conductivity as well as laser parameters. LB-PBF has more influential factors affecting the quality of produced parts and is a more complex process. Both LB-SM and LB-PBF are flexible manufacturing methods that can be applied to a wide range of materials; however, they both suffer from low energy efficiency and production rate. These may be useful when producing highly innovative parts detailed, hollow products, such as medical implants.

This paper reviews the literature for both LB-PBF and LB-SM; nevertheless, the main contributions of this paper are twofold. To the best of the authors’ knowledge, this paper is one of the first to discuss the effect of the production process (both additive and subtractive) on the quality of the produced components. Also, some options for the hybrid capability of both LB-PBF and LB-SM are suggested to produce complex components with the desired macro- and microscale features.

Rapid tooling (RT) integrated with additive manufacturing technologies have been implemented in various sectors of the RT industry in recent years with various kinds of prototype applications, especially in the development of new products. The purpose of this study is to analyze the current application trends of RT techniques in producing hybrid mold inserts.

The direct and indirect RT techniques discussed in this paper are aimed at developing a hybrid mold insert using metal epoxy composite (MEC) in increasing the speed of tooling development and performance. An extensive review of the suitable development approach of hybrid mold inserts, material preparation and filler effect on physical and mechanical properties has been conducted.

Latest research studies indicate that it is possible to develop a hybrid material through the combination of different shapes/sizes of filler particles and it is expected to improve the compressive strength, thermal conductivity and consequently increasing the hybrid mold performance (cooling time and a number of molding cycles).

The number of research studies on RT for hybrid mold inserts is still lacking as compared to research studies on conventional manufacturing technology. One of the significant limitations is on the ways to improve physical and mechanical properties due to the limited type, size and shape of materials that are currently available.

This review presents the related information and highlights the current gaps related to this field of study. In addition, it appraises the new formulation of MEC materials for the hybrid mold inserts in injection molding application and RT for non-metal products.

A new kind of polymer mixture (co-PA-PES) was prepared in different mass ratios, by mixing polyether sulfone hot-melt adhesive (PES-HmA) and copolyamide B249 (PA-B249). This study aims to investigate its characteristics of laser sintering and get the optimal process parameters.

The effect of mass ratio of co-PA-PES on thermal behavior was analyzed using a simultaneous thermal analyzer, and the density and mechanical properties of sintered parts were tested to evaluate the performance of the polymeric system. Scanning electron microscopy and Fourier transform infrared spectroscopy were performed to characterize the microstructure and binding mechanism of sintered co-PA-PES parts. Specifically, mechanical properties of the mixture with 20 Wt.% PA-B249 were optimized based on a design of experiment methodology, along with the restriction of maximum absorbable laser energy density.

Liquid phase fusion was considered as the main sintering mechanism for co-PA-PES, and mechanical interlocking was the dominant binding mechanism. The effects of mass ratios of this material on the thermal properties, density and mechanical properties were obtained via data results. Additionally, compared to neat PES-HmA, co-20 Wt.% PA-PES showed a 71.7 per cent increase in tensile strength, 24.4 per cent increase in flexural strength and 102.1per cent increase in impact strength.

This paper proposed a new kind of polymer mixture as the feedstock for laser sintering with the advantages of low price and easy processing. The filler of PA-B249 effectively improved the performance of the polymer mixture, including but not limited to mechanical properties.

The purpose of this paper is to examine how the instructions of the lean startup methodology influence entrepreneurs. It explores what happens when such instructions are enacted by entrepreneurs in the context of a “prescriptive accelerator”. The goal is to shine a light onto the mechanisms by which these instructions are acquired and then utilised by entrepreneurs and to outline in some detail the implications of adhering to the lean startup methodology.

This paper employs an in-depth phenomenological semi-structured interview design. Two rounds of interviews were conducted, one at the beginning and one at the end of the programme with the CEOs and founders of 11 entrepreneurial ventures, totalling 22 interviews. The analysis of the interviews resulted in five second-order themes that are discussed in light of the processes of experiential and vicarious learning.

The findings suggest that through two distinct modes of vicarious and experiential learning, the instructions of the lean startup methodology are acquired, internalised and consequently put into practice by entrepreneurs. The paper further highlights the modifications to entrepreneurs’ governing variables and action strategies, as well as the resulting consequences of these modifications. This provides insights into possible outcomes of following the lean startup methodology in the context of a prescriptive accelerator where a strong focus on adhering to a systematic entrepreneurial methodology is a characteristic feature.

This paper contributes to our understanding of the under-studied and novel phenomena of the lean startup methodology and prescriptive accelerators. It complements the prevailing understanding of entrepreneurial learning as being largely experiential by accounting for the vicarious learning processes that occur in pedagogical settings such as prescriptive accelerators. It therefore shows that prescriptive accelerators provide unique learning situations where the combination of vicarious and experiential learning impacts the business development activities. Further, it provides a model of entrepreneurs’ theory of action as the outcome of the interactions between the lean startup methodology and the two modes of vicarious and experiential learning.

Energy analysis (EA) within a building information modelling (BIM) enables consistent data integration in central repositories and eases information exchange, reducing rework. However, data loss during information exchange from different BIM uses or disciplines is frequent. Therefore, a holistic approach for different BIM uses enables a coherent life cycle information flow. The life cycle information flow drives the reduction of data loss and model rework and enhances the seamless reuse of information. The latter requires a specification of the EA key performance indicators (KPIs) and integrating those in the process.

The paper presents a set of KPIs extracted from the developed EA process maps and interviews with expert stakeholders. These KPIs stem from the literature review and link to the benefits of EA through industry expert review. The study includes (1) development and validation of EA process maps adjusted to requirements from different stakeholders. (2) KPIs aligned with the EA process map, (3) identification of the drivers that can facilitate life cycle information exchange and (4) opportunities and obstacles for EA within BIM-enabled projects.

This paper depicts a viable alternative for EA process maps and KPIs in a BIM-enabled AEC design industry. The findings of this paper showcase the need for an EA within BIM with these KPIs integrated for a more effective process conforming to the current Open BIM Alliance guidance and contributing towards sustainable life cycle information flow.

The limitation of the research is the challenge of generalising the developed EA process maps; however, it can be adjusted to fit defined organisational use. The findings deduced from the developed EA process map only show KPIs to have the ability to facilitate adequate information flow during EA.

The AEC industry will benefit from the findings of this primary research as the industry will be able to contrast its process maps and KPIs to those developed in the paper.

This paper benefits the societal values in EA for the built environment in the design stages. The subsequent life cycle information flow will help achieve a consistent information set and decarbonised built environment.

The paper offers a practical overview of process maps and KPIs to embed EA into BIM, reducing the information loss and rework needed in the practice of this integration. The applicability of the solution is contrasted by consultation with experts and literature.