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The purpose of this paper is to concern with using municipal solid waste incineration bottom ash (MSWI-BA) in concrete application.

In this paper, the performance of reinforced concrete (RC) beams containing MSWI-BA was investigated. Four concrete mixes were used in this study. The control mix had a proportion of 1 (cement): 2 (fine aggregates): 4 (coarse aggregates) by weight. In the other three mixes, the fine aggregates were partially replaced with 20%, 40% and 60% MSWI-BA (by weight). The water to cement ratio was kept constant at 0.5 in all mixes. Concrete cubes and cylinders were prepared to determine some physical and mechanical properties of concrete, whereas RC beams were used for determining the structural performance.

There was an increase in compressive strength, tensile strength and the modulus of elasticity when 20% of fine aggregates were replaced with MSWI-BA. However, beyond 20% these properties were reduced. The load bearing capacity and deflection were the highest for the control beam and the beam with 20% MSWI-BA.

The research conducted in this investigation used a specific type of MSWI-BA. The composition of the waste can vary from one plant to another and this presents one of the limitations.

The findings of this research indicate that MSWI-BA can partially substitute fine aggregate, thus reducing the impact of construction on the environment.

The MSWI-BA used in this research differs from other types as the waste papers and cartons are removed from the waste and used to produce other products. Therefore, this study is considered original as it examines MSWI-BA with different properties for use in construction.

This study deals with three major topics: (1) the developed generations of 3D concrete printers, (2) the mix design approach for cement-based materials and (3) laboratory testing.

The big question is how to approach and follow the trend of 3D concrete printing technology with limited conditions such as printers, technology issues and budget. Therefore, this research focused on dealing with prominent issues, including printing equipment, mixed proportion design approaches and laboratory testing methods will be presented and analyzed.

The details of three printing equipment, including a printhead, a small-scale 3D printer, a 3D concrete printer and the printing process related to Simplify and Mach3 software, will be revealed. Secondly, the classification and efficient process will be given according to the mixture proportion design method proposed. Thirdly, laboratory testing will be conducted, including extrudability, buildability and printability. Finally, some highlight conclusions are given based on the appearance and quality of the samples printed.

Research has been carried out with cement-based materials and 3D concrete printer which adopted the screw extruders.

Mix design proportion method via coefficient and slump value proposed by the authors is a relatively effective and convenient method; the rheological properties, printing process and geometry of a sample are the most significant factors that decide the success of the printing work.

Additive manufacturing, widely known as 3D printing, has recently drawn the attention of researchers worldwide for a few decades. Thanks to its capability to transform a drawing into an object, the idea of 3D printing has also attracted the attention of engineers, architects and investors.

(1) Mix design proportion via coefficient and slump value proposed by the authors is a relatively effective and convenient method that can be implemented simply at the laboratory or the site. (2) The ranges of coefficients by weight of the water, sand and PP fibers to binder are (0.27–0.3), (0.6–1.0) and around 0.3, respectively. The maximum sand size was smaller than 2.5 mm, and the small amount of PP fibers enhanced the quality and significantly reduced the printed samples' shrinkage. (3) The printability is affected by mix proportion and the relationship between nozzle printing speed parameter and extrusion speed of motor turning. (4) The chosen layer height recommended smaller than 0.83 times nozzle diameter is reasonable and improves adhesions and buildability. (5) The printing open time of the concrete mixture of (12–15) minutes is a barrel to promote 3D concrete printing technology and needs improvement.

The purpose of the study is an in-depth exploration of the processes through which a leader develops their leader identity in strength, meaning and integration, with resulting enrichment outcomes.

Using multi-domain leader identity theory, this study provides an in-depth exploration of the processes through which a leader develops their leader identity. Set in a healthcare context, 26 participants took part in an 18-month multi-domain leadership development program.

Findings indicate a typology of leader identities, capturing the dynamic nature of leader identity based on combinations of strength and meaning. Our research also suggests that as the leader develops, their leader identity can change from a differentiated identity as a leader to a more integrated leader identity, with resulting enrichment outcomes.

The results suggested value in inherently multi-domain focus using event-based reflection and, as such, are useful in leader identity development programs. We recommend future research generalize to other settings and a larger population.

By taking a multi-domain approach to leader identity development, the leader has the opportunity to learn and develop in a more holistic way. They are encouraged to reflect on and learn from leadership experiences throughout their entire lives, adding breadth and depth that are often overlooked in development programs.

Developing leaders who understand who they are and are capable of critical self-reflection and learning is a fundamental requirement for the positive advancement of society.

The value of the study lies in the first longitudinal, work-based empirical study taking an explicitly multi-domain approach to leader identity development.

This paper aims to examine how the fields of social enterprise, social entrepreneurship and social innovation have theorised and applied the concepts of narrative and storytelling.

A literature review and subsequent thematic analysis were used. A keyword search of three databases identified 93 relevant articles that were subsequently reviewed for this paper.

Four main roles for storytelling and narrative were found in the literature: to gain support for social innovation, to inspire social change, to build a social-entrepreneurial identity and to debate the meaning and direction of social innovation itself.

Following the literature review, capacities and applications of storytelling and narrative in other, related fields are discussed to highlight practical use cases of storytelling that might currently be underdeveloped in the social enterprise and innovation sectors.

The paper argues that the social innovation and enterprise literature predominantly views storytelling as a form of mass communication, while often overlooking its ability to foster communal debate and organise intrapersonal dialogue as possible aspects of strategic thinking and innovation management in social enterprise, social entrepreneurship and social innovation.