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Instructional leadership has been an active area of educational administration research over the past 30 years. However, there has been significant divergence in how instructional leadership has been conceptualized over time. The purpose of this paper is to present a comprehensive review of 25 years of quantitative instructional leadership research, up through 2013, using a nationally generalizable data set.

The authors conducted a meta-narrative review of 109 studies that investigated at least one aspect of instructional leadership using the Schools and Staffing Survey (SASS) administered by the US National Center for Education Statistics.

There were four major themes of instructional leadership research that analyzed SASS data: principal leadership and influence, teacher autonomy and influence, adult development, and school climate. The three factors most researched in relationship to instructional leadership themes were: teacher satisfaction, teacher commitment, and teacher retention. This study details the major findings within each theme, describes the relationships between all seven factors, and integrates the relationships into a single model.

This paper provides the most comprehensive literature review to-date of quantitative findings investigating instructional leadership from the same nationally generalizable data set. This paper provides evidence that leadership for learning is the conceptual evolution of 25 years of diverse instructional leadership research.

This chapter examines the characteristics, challenges and prospects of environmental governance and participation in issues pertaining to human health and the ocean in the CARICOM Caribbean region.

Utilising the fisheries sector – one of the principal economic, social and environmental drivers relating to the marine environment in the Caribbean region – we discuss the concepts of hierarchical governance in contradistinction to heterarchical governance. This is done through a socio-legal analysis of the predominant top-down model of governance, a discussion of the successes and shortcomings of bottom-up governance and a proposal for more inclusive participation methodologies in the region.

While the paradigm of new collaborative environmental governance was birthed in the aftermath of the 1985 Brundtland Commission Report, and moreso since the 1992 Rio Conference, this analysis will show that governance of the marine resource, and consequently how the individual is juxtaposed within this matrix, has not shifted from a position of hierarchy to one of heterarchy, as prescribed by the governance literature. Indeed, the structures for governance remain largely top-down in nature and while many states have begun to embrace more inclusive and participatory methodologies many of these interventions will need to be bolstered if the governance of the region’s marine resources is to progress from traditional top-down to more inclusive and representative typologies.

These concepts, when applied to the subject of environmental governance, will demonstrate that there needs to be an improvement in participatory environmental governance in the CARICOM region if the integrity of human health and the ocean is to be maintained. Importantly, while these methodologies strive for the formulation prescribed in Principle 10 of the 1992 Rio Declaration, and most famously exemplified in the 1998 Aarhus Convention, issues of environmental advocacy, transparency, inequality and justice need to be reconceptualised, if the region is to see prudent governance of the interface between humans and the ocean.

This research takes established concepts on the issue of locus standi in the common law legal tradition and juxtaposes it within the emerging paradigm of ecohealth and environmental governance. This conceptual framework has identified both the prospects and problems of environmental governance in the Caribbean region and may provide the basis for further research as well as more inclusive and sustainable environmental governance.

In spite of ongoing and recent initiatives aimed at broadening participation in engineering, the representation of diverse groups of learners in engineering graduate programs in the USA remains a challenge. Foregrounding the voices of 26 Black male engineering faculty, this study aims to investigate how institutions might recruit and retain more Black men in engineering graduate programs.

For this study, inductive thematic analysis was used.

The authors show that three themes, namely, representation as an asset, invested mentors and faculty, and supportive peer networks described as the “Vibe” manifest as crucial elements for successful recruitment and retention of Black men in engineering graduate programs.

These findings are meant to augment the conversation around diversity, equity and inclusion in engineering graduate programs and to address a dearth of published research on the Black male engineering population. This work is also meant to help institutions conceptualize ways to create a “Vibe” that might be transferable to their institution’s sociocultural context.

There are many investigations in design methodologies, but there are also divergences and convergences as there are so many points of view. This study aims to evaluate to corroborate and deepen other researchers’ findings, dissipate divergences and provide directing to future work on the subject from a methodological and convergent perspective.

This study analyzes the previous reviews (about 15 reviews) and based on the consensus and the classifications provided by these authors, a significant sample of research is analyzed in the design for additive manufacturing (DFAM) theme (approximately 80 articles until June of 2017 and approximately 280–300 articles until February of 2019) through descriptive statistics, to corroborate and deepen the findings of other researchers.

Throughout this work, this paper found statistics indicating that the main areas studied are: multiple objective optimizations, execution of the design, general DFAM and DFAM for functional performance. Among the main conclusions: there is a lack of innovation in the products developed with the methodologies, there is a lack of exhaustivity in the methodologies, there are few efforts to include environmental aspects in the methodologies, many of the methods include economic and cost evaluation, but are not very explicit and broad (sustainability evaluation), it is necessary to consider a greater variety of functions, among other conclusions

The novelty in this study is the methodology. It is very objective, comprehensive and quantitative. The starting point is not the case studies nor the qualitative criteria, but the figures and quantities of methodologies. The main contribution of this review article is to guide future work on the subject from a methodological and convergent perspective and this article provides a broad database with articles containing information on many issues to make decisions: design methodology; optimization; processes, selection of parts and materials; cost and product management; mechanical, electrical and thermal properties; health and environmental impact, etc.

This paper aims to review recent research in design for additive manufacturing (DfAM), including additive manufacturing (AM) terminology, trends, methods, classification of DfAM methods and software. The focus is on the design engineer’s role in the DfAM process and includes which design methods and tools exist to aid the design process. This includes methods, guidelines and software to achieve design optimization and in further steps to increase the level of design automation for metal AM techniques. The research has a special interest in structural optimization and the coupling between topology optimization and AM.

The method used in the review consists of six rounds in which literature was sequentially collected, sorted and removed. Full presentation of the method used could be found in the paper.

Existing DfAM research has been divided into three main groups – component, part and process design – and based on the review of existing DfAM methods, a proposal for a DfAM process has been compiled. Design support suitable for use by design engineers is linked to each step in the compiled DfAM process. Finally, the review suggests a possible new DfAM process that allows a higher degree of design automation than today’s process. Furthermore, research areas that need to be further developed to achieve this framework are pointed out.

The review maps existing research in design for additive manufacturing and compiles a proposed design method. For each step in the proposed method, existing methods and software are coupled. This type of overall methodology with connecting methods and software did not exist before. The work also contributes with a discussion regarding future design process and automation.

Additive manufacturing (AM) technologies are gaining immense popularity in the manufacturing sector because of their undisputed ability to construct geometrically complex prototypes and functional parts. However, the reliability of AM processes in providing high-quality products remains an open and challenging task, as it necessitates a deep understanding of the impact of process-related parameters on certain characteristics of the manufactured part. The purpose of this study is to develop a novel method for process parameter selection in order to improve the dimensional accuracy of manufactured specimens via the fused deposition modeling (FDM) process and ensure the efficiency of the procedure.

The introduced methodology uses regression-based machine learning algorithms to predict the dimensional deviations between the nominal computer aided design (CAD) model and the produced physical part. To achieve this, a database with measurements of three-dimensional (3D) printed parts possessing primitive geometry was created for the formulation of the predictive models. Additionally, adjustments on the dimensions of the 3D model are also considered to compensate for the overall shape deviations and further improve the accuracy of the process.

The validity of the suggested strategy is evaluated in a real-life manufacturing scenario with a complex benchmark model and a freeform shape manufactured in different scaling factors, where various sets of printing conditions have been applied. The experimental results exhibited that the developed regressive models can be effectively used for printing conditions recommendation and compensation of the errors as well.

The present research paper is the first to apply machine learning-based regression models and compensation strategies to assess the quality of the FDM process.

The purpose of this paper is to develop a numerical approach inspired by Geometrical Product Specifications (GPS) standards for the assessment of geometrical defects appearing during Additive Manufacturing (AM) by Laser Beam Melting (LBM).

The study is based on finite element (FE) simulations of thermal distortions, then an assessment of flatness defects (warping induced by the high-residual stresses appearing during the manufacturing) from the deformed surfaces provided by simulation, and finally the correction of the calculated flatness defects from preliminary comparison between simulated and experimental data.

For an elementary geometrical feature (a wall), it was possible to identify the variation in the flatness defect as a function of the dimensions. For a complex geometry exhibiting a significant flatness defect, it was possible to improve the geometric quality using the numerical tool.

To the best of the author’s knowledge, this work is the first attempt using a numerical approach inspired by GPS standards to identify variations in thermal distortions caused by LBM, which is an initial step toward optimization. This paper is mainly focused on flatness defect assessment, even though the approach is potentially applicable for all types of geometrical defects (shape, orientation or position defects).

The study opens prospects for the optimization of complex parts elaborated using LBM, based on the minimization of the geometric defects caused by thermal distortions.

The prospects in terms of shape optimization will extend the potential to benefit from the new possibilities offered by LBM additive manufacturing.

Unlike the usual approach, the proposed methodology does not require any artifacts or comparisons with the computer-aided-design (CAD) model for geometrical distortion assessment. The present approach opens up the possibility of performing metrology from FE simulation results, which is particularly promising in the AM field.

Wire + arc additive manufacturing (WAAM) uses existing welding technology to make a part from metal deposited in an almost net shape. WAAM is flexible in that it can use multiple materials successively or simultaneously during the manufacturing of a single component.

In this work, a gas metal arc welding (GMAW) based wire + arc additive manufacturing (WAAM) system has been developed to use two material successively and fabricate bimetallic additively manufactured structure (BAMS) of low carbon steel and AISI 316L stainless steel (SS).

The interface shows two distinctive zones of LCS and SS deposits without any weld defects. The hardness profile shows a sudden increase of hardness at the interface, which is attributed to the migration of chromium from the SS. The tensile test results show that the bimetallic specimens failed at the LCS side, as LCS has lower strength of the materials used.

The microstructural features and mechanical properties are studied in-depth with special emphasis on the bimetallic interface.

The aim of this paper is to qualitatively examine the ways in which primary school children, aged between 7 and 12, perceive various facets of obesity as defined by the common sense model of illness representation (CCM).

The study was qualitative in nature. Semi‐structured interviews were conducted with 33 children on all dimensions of the CSM. Twenty four children were normal weight and nine were overweight. A drawing task formed the methodology for the “identity” section of the interview.

Although children identified food intake as a main cause of obesity, almost half did not name sedentary behaviours as a cause of obesity. Duration (timeline) of obesity was regarded by most children as reliant on a person's undertaking of positive health behaviours. Normal weight children were found to list more severe consequences of obesity than the overweight group. It was found that experience contributed to the detailed knowledge of overweight children's perceptions of cures of obesity. Overweight children also spoke of personal incidents of barriers to cures.

The findings suggest that the CSMs can be used to classify children's perceptions of obesity. Future childhood obesity interventions can utilise these findings to create campaigns and strategies that are more consistent with children's understandings of this condition.

To the authors' knowledge, no previous study has examined children's perceptions of obesity beyond perceived causes.

There is no argument among serious researchers that a mongoloid stock first colonized the New World from Asia. Nor is there controversy about the fact that these continental pioneers used the Bering Land Bridge that then connected the Asian Far East with Alaska.– Gerald F. Shields, et al.American Journal of Genetics (1992)