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This paper aims to present a comprehensive review of the laser engineered net shaping (LENS) process in an attempt to provide the reader with a deep understanding of the controllable and fixed build parameters of metallic parts. The authors discuss the effect and interplay between process parameters, including: laser power, scan speed and powder feed rate. Further, the authors show the interplay between process parameters is pivotal in achieving the desired microstructure, macrostructure, geometrical accuracy and mechanical properties.

In this manuscript, the authors review current research examining the process inputs and their influences on the final product when manufacturing with the LENS process. The authors also discuss how these parameters relate to important build aspects such as melt-pool dimensions, the volume of porosity and geometry accuracy.

The authors conclude that studies have greatly enriched the understanding of the LENS build process, however, much studies remains to be done. Importantly, the authors reveal that to date there are a number of detailed theoretical models that predict the end properties of deposition, however, much more study is necessary to allow for reasonable prediction of the build process for standard industrial parts, based on the synchronistic behavior of the input parameters.

This paper intends to raise questions about the possible research areas that could potentially promote the effectiveness of this LENS technology.

This contribution investigates methodological questions concerning Change Laboratory interventions. It contemplates the research questions: To what extent the Change Laboratory can be situated within the panorama of qualitative inquiry? If so, to what extent can the methods and strategies of inquiry help improve a Change Laboratory intervention?

To answer the first question, this paper makes an overview on key terms of qualitative research; subsequently, it presents the characterising features of the Change Laboratory. Then, it takes a historical perspective and compares the Change Laboratory firstly against action research, and secondly with design experiments. To answer the second section, it examines a case study of Change Laboratory with teachers that the first author facilitated. Next, it displays how trustworthiness was ensured through a thick description and member checks.

The paper argues that the Change Laboratory is a strategy of inquiry; it aligns with the characteristics of qualitative research, and it follows the agenda of a participative paradigm. Furthermore, the methods and strategies of inquiry such as thick descriptions and member checks, not only can improve rigour and validity of the intervention but also strengthen the outcomes of the Change Laboratory itself.

The Change Laboratory is well defined as a formative method, but not fully understood as an investigative method. Although scholars discussed methodological issues of Cultural Historical Activity Theory in diverse articles, the relationship between the Change Laboratory and qualitative inquiry has remained unclear.