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Article
Publication date: 2 May 2017

Robert Straka and Tadeusz Telejko

The model of a shaft furnace operation is presented in this paper. Aim of this model is to predict concentrations of carbon monoxide and dioxide, the temperature of the…

Abstract

Purpose

The model of a shaft furnace operation is presented in this paper. Aim of this model is to predict concentrations of carbon monoxide and dioxide, the temperature of the lava and the heat losses.

Design/methodology/approach

The mathematical model is based on 1D mass and heat balance laws for flue gas, coke and four materials used in a mineral wool production. Process parameters should be optimized for the minimal heat loss and the carbon monoxide concentration while keeping the prescribed lava temperature. The model consists of heterogeneous and homogeneous reactions for coke combustion, dolomite decomposition, rock and coke heating and a rock-melting model. The resulting system of partial differential equations is discretized by the finite volume method and solved with the explicit Euler scheme together with the point-implicit preconditioning of sources in species balance equations.

Findings

Numerical results are compared with the measured data on the pilot-scale device and show good agreement. It is found that in the lower region of the furnace, the large amount of carbon monoxide is present despite high oxygen levels.

Practical/implications

Based on the numerical model, the parameters of the secondary air stream could be studied (position, volume flux, oxygen enrichment and temperature) to decrease levels of carbon monoxide emissions while keeping lava temperature at needed levels.

Originality/value

The paper includes mathematical and numerical model needed for simulation of shaft furnaces in mineral wool industry. It can be used as a valuable tool for design engineers and furnace operators during research or redesign of existing devices.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 27 no. 5
Type: Research Article
ISSN: 0961-5539

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Article
Publication date: 8 July 2019

Łukasz Łach, Dmytro Svyetlichnyy and Robert Straka

A fundamental principle of materials engineering is that the microstructure of a material controls the properties. The phase transformation is an important phenomenon that…

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Abstract

Purpose

A fundamental principle of materials engineering is that the microstructure of a material controls the properties. The phase transformation is an important phenomenon that determines the final microstructure. Recently, many analytical and numerical methods were used for modeling of phase transformation, but some limitations can be seen in relation to the choice of the shape of growing grains, introduction of varying grain growth rate and modeling of diffusion phenomena. There are also only few comprehensive studies that combine the final microstructure with the actual conditions of its formation. Therefore, the objective of the work is a development of a new hybrid model based on lattice Boltzmann method (LBM) and cellular automata (CA) for modeling of the diffusional phase transformations. The model has a modular structure and simulates three basic phenomena: carbon diffusion, heat flow and phase transformation. The purpose of this study is to develop a model of heat flow with consideration of enthalpy of transformation as one of the most important parts of the proposed new hybrid model. This is one of the stages in the development of the complex model, and the obtained results will be used in a combined solution of heat flow and carbon diffusion during the modeling of diffusion phase transformations.

Design/methodology/approach

Different values of overheating/overcooling affect different values in the enthalpy of transformation and thus the rate of transformation. CA and LBM are used in the hybrid model in part related to heat flow. LBM is used for modeling of heat flow, while CA is used for modeling of the microstructure evolution during the phase transformation.

Findings

The use of LBM and CA in one numerical solution creates completely new possibilities for modeling of phase transformations. CA and LBM in comparison with commonly used approaches significantly simplify interface and interaction between different parts of the model, which operates in a common domain. The CA can be used practically for all possible processes that consist of nucleation and grains growth. The advantages of the LBM method can be well used for the simulation of heat flow during the transformation, which is confirmed by numerical results.

Practical implications

The developed heat flow model will be combined with the carbon diffusion model at the next stage of work, and the new complex hybrid model at the final stage will provide new solutions in numerical simulation of phase transformations and will allow comprehensive modeling of the diffusional phase transformations in many processes. Heating, annealing and cooling can be considered.

Originality/value

The paper presents the developed model of heat flow (temperature module), which is one of the main parts of the new hybrid model devoted to modeling of phase transformation. The model takes into account the enthalpy of transformation, and the connection with the model of microstructure evolution was obtained.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 30 no. 5
Type: Research Article
ISSN: 0961-5539

Keywords

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Article
Publication date: 2 January 2018

Dmytro Svyetlichnyy, Michal Krzyzanowski, Robert Straka, Lukasz Lach and W. Mark Rainforth

The holistic numerical model based on cellular automata (CA) and lattice Boltzmann method (LBM) are being developed as part of an integrated modelling approach applied to…

Abstract

Purpose

The holistic numerical model based on cellular automata (CA) and lattice Boltzmann method (LBM) are being developed as part of an integrated modelling approach applied to study the interaction of different physical mechanisms in laser-assisted additive layer manufacturing (ALM) of orthopaedic implants. Several physical events occurring in sequence or simultaneously are considered in the holistic model. They include a powder bed deposition, laser energy absorption and heating of the powder bed by the moving laser beam, leading to powder melting or sintering, fluid flow in the melted pool and flow through partly or not melted material, and solidification. The purpose of this study is to develop a structure of the holistic numerical model based on CA and LBM applicable for studying the interaction of the different physical mechanisms in ALM of orthopaedic implants. The model supposed to be compatible with the earlier developed CA-based model for the generation of the powder bed.

Design/methodology/approach

The mentioned physical events are accompanied by heat transfer in solid and liquid phases including interface heat transfer at the boundaries. The sintering/melting model is being developed using LBM as an independent numerical method for hydrodynamic simulations originated from lattice gas cellular automata. It is going to be coupled with the CA-based model of powder bed generation.

Findings

The entire laser-assisted ALM process has been analysed and divided on several stages considering the relevant physical phenomena. The entire holistic model consisting of four interrelated submodels has currently been developed to a different extent. The submodels include the CA-based model of powder bed generation, the LBM-CA-based model of heat exchange and transfer, the thermal solid-liquid interface model and the mechanical solid-liquid interface model for continuous liquid flow.

Practical implications

The results obtained can be used to explain the interaction of the different physical mechanisms in ALM, which is an intensively developing field of advanced manufacturing of metal, non-metal and composite structural parts, for instance, in bio-engineering. The proposed holistic model is considered to be a part of the integrated modelling approach being developed as a numerical tool for investigation of the co-operative relationships between multiphysical phenomena occurring in sequence or simultaneously during heating of the powder bed by the moving high energy heat source, leading to selective powder sintering or melting, fluid flow in the melted pool and through partly (or not) melted material, as well as solidification. The model is compatible with the earlier developed CA-based model for the generation of the powder bed, allowing for decrease in the numerical noise.

Originality/value

The present results are original and new for the study of the complex relationships between multiphysical phenomena occurring during ALM process based on selective laser sintering or melting, including fluid flow and heat transfer, identified as crucial for obtaining the desirable properties.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 28 no. 1
Type: Research Article
ISSN: 0961-5539

Keywords

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Article
Publication date: 6 September 2018

Allison Earl, Robert VanWynsberghe, Pierre Walter and Timothy Straka

This paper aims to present an interpretive case study in education for sustainability (EfS) that applies VanWynsberghe and Herman’s (2015, 2016) adaptive education as…

Abstract

Purpose

This paper aims to present an interpretive case study in education for sustainability (EfS) that applies VanWynsberghe and Herman’s (2015, 2016) adaptive education as pedagogy. Dewey’s theory of behaviour change is applied to educative experiences based on habit disruption and real-world learning, leading to creativity in the formation of new habits. The programme presented inverts dominant conceptions of knowledge to design innovative sustainability pedagogy. Instead knowledge resides alongside experience, cases, intuition, advice, experimentation and dialogue in the individual and collective effort to address daily sustainability challenges.

Design/methodology/approach

The paper reports on the outcomes of an interpretive case study (Merriam, 1998) of a higher education programme in sustainability pedagogy. It presents a series of reflections by instructors and participants in discussing the programme’s relationship with the core themes of habit, disruption, creative action and dialogue framed within the five features of adaptive education: stakeholders, real-world learning, off campus, transdisciplinarity and non-traditional rewards.

Findings

Through this examination, the authors found that adaptive education offered a pedagogy that simultaneously addressed the need for increased sustainability knowledge, whilst inverting its dominance. As a long-term project, the extent of the programme’s impact will be evident beyond the programme’s completion.

Research limitations/implications

This interpretive case study is analysed through high-level conceptual and theoretical aspects of the pedagogy rather than the particularities of the case. By putting the centrality of knowledge into question, the authors are advocating for a more experimental role for higher education in its teaching and learning. These questions are broadly applicable.

Social implications

There are research, learning and social benefits to this programme. Adaptive education builds capacity for future leaders and educators of sustainability.

Originality/value

The paper concludes with a discussion for further theorizing and research on adaptive education and EfS in higher education. This research will contribute to broader discussions of the evolving role of education in sustainability.

Details

International Journal of Sustainability in Higher Education, vol. 19 no. 6
Type: Research Article
ISSN: 1467-6370

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Book part
Publication date: 18 November 2015

Verena Eberhard, Stephanie Matthes and Joachim Gerd Ulrich

Human beings are dependent upon social approval to strengthen their identities. Therefore, they practice impression management: They anticipate which behaviour provokes…

Abstract

Human beings are dependent upon social approval to strengthen their identities. Therefore, they practice impression management: They anticipate which behaviour provokes which reactions in their social environment, and they tend to exhibit the kind of behaviour that promises positive feedback. Based on the assumption that human beings also show this behaviour in their choice of vocation, we hypothesise that young people are more likely to expect negative reactions from their social environment when choosing a gender-atypical occupation. Furthermore, we assume that the expected reaction of the social environment influences vocational orientation: The anticipation of negative reactions to gender-atypical vocational choice might contribute to explain why young people ignore this occupation. We tested both hypotheses with the help of data retrieved from a survey of young people in Germany who are interested in vocational education and training (VET). The results support our hypotheses; however, they also show that the relevance of a gender-typed vocational choice is weaker if adolescents have a higher educational background. In this case, the choice of an occupation that expresses a high educational status becomes more important. It may lead to an exclusive kind of social approval that is denied to people with a lower educational background.

Details

Gender Segregation in Vocational Education
Type: Book
ISBN: 978-1-78560-347-1

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Article
Publication date: 31 May 2007

Jiri Strouhal

Year 2004 was influenced by the strike in the National Hockey League. The reason of this strike was the option of adoption of the wage ceiling for the NHL players. The…

Abstract

Year 2004 was influenced by the strike in the National Hockey League. The reason of this strike was the option of adoption of the wage ceiling for the NHL players. The paper stresses the attention to the problem how to account and measure the possibility of the players’ contracts with options in the new model. We are dealing with the following hypothesis: “Is possible to use the experiences of valuation of financial options not only to ROA (Real Options Analysis) but also for valuation of players’ contracts with option?” The modified Black‐Scholes Formula is one of the possible solutions how to measure the value of the option clause.

Details

Journal of International Trade Law and Policy, vol. 6 no. 1
Type: Research Article
ISSN: 1477-0024

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Book part
Publication date: 19 February 2020

Cosma Orsi

From 1782 to 1834, the English social legislation shifted from a safety net devised to deal with emergencies to a social security system implemented to cope with the…

Abstract

From 1782 to 1834, the English social legislation shifted from a safety net devised to deal with emergencies to a social security system implemented to cope with the threat of unemployment and poverty. In the attempt to explain this shift, this chapter concentrates on the changed attitudes toward poverty and power relationships in eighteenth-century British society. Especially, it looks at the role played by eighteenth-century British economic thinkers in elaborating arguments in favor of reducing the most evident asymmetries of power characterizing the period of transition from Mercantilism to the Classical era. To what extent did economic thinkers contribute to creating an environment within which a social legislation aimed at improving the living conditions of the poor as the one established in 1795 could be not only envisaged but also implemented? In doing so, this chapter deals with an aspect often undervalued and/or overlooked by historians of economic thought: namely, the relationship between economic theory and social legislation. If the latter is the institutional framework by which both individual and collective well-being can be achieved the former cannot but assume a fundamental role as a useful abstraction which sheds light on the multifaceted reality in which social policies are proposed, forged, and eventually implemented.

Details

Research in the History of Economic Thought and Methodology: Including a Symposium on Public Finance in the History of Economic Thought
Type: Book
ISBN: 978-1-83867-699-5

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Article
Publication date: 1 March 2002

Thomas N. Garavan, Michael Morley, Patrick Gunnigle and David McGuire

Workplace learning and HRD are considered legitimate topics for study and investigation alongside organisational strategies and practices. Considers key themes in the…

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Abstract

Workplace learning and HRD are considered legitimate topics for study and investigation alongside organisational strategies and practices. Considers key themes in the workplace earning literature in addition to its relationship with HRD. Identifies a paradigm shift from formalised, intermittent and discontinuous learning to increasingly informal, experiential, asynchronous and real‐time situated learning. Highlights three contemporary themes in both the workplace learning and HRD literatures, namely: knowledge, expertise, competence and capability; organisational learning; and employability and career issues.

Details

Journal of European Industrial Training, vol. 26 no. 2/3/4
Type: Research Article
ISSN: 0309-0590

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Content available
Book part
Publication date: 8 June 2020

Rupert Ward

Abstract

Details

Personalised Learning for the Learning Person
Type: Book
ISBN: 978-1-78973-147-7

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Article
Publication date: 21 February 2020

Margarita Pacis and Robert VanWynsberghe

The purpose of this paper is to posit that a key sustainability tool can help provide a needed guide for the many forms of new curricula for academic, public and…

Abstract

Purpose

The purpose of this paper is to posit that a key sustainability tool can help provide a needed guide for the many forms of new curricula for academic, public and professional learning communities. The authors demonstrate that key sustainability competency (KSC) research can highlight and provide an array of learning outcomes that can be back cast to co-design flexible, detailed curriculum, pedagogy, practice and assessment structures. They also briefly outline the connection of KSC to education for sustainability (EfS) to provide the educational basis for designing and facilitating classrooms that contribute directly to the sustainability movement.

Design/methodology/approach

This paper is a review of literature with a specific focus on Glasser's (2018b) promising use of the tree as an analogy and metaphor for KSCs.

Findings

Some, for example, Glasser and Hirsh (2016) claim significant progress in identifying a KSC framework (Wiek et al., 2011) However, the authors raise concerns about the impasse that the literature has demonstrated because these stand in the way of the co-creation of sustainable societies by adjusting how we learn and interact with the world. The authors argue that we must realize and disrupt the destructive actions that form their usual approach and replace them with sustainable habits (Glasser, 2018a), and this requires the emergence of a new class of sustainability practitioners with the skills, attitudes and dispositions that are consistent with being wise, future-oriented, interdisciplinary and global decision-makers (Biasutti, 2015; Biasutti and Frate, 2016; Corney and Reid, 2007; McNaughton, 2012; Scoullos, 2013).

Research limitations/implications

Using Glasser’s metaphor, the authors assert a process through which the future sustainability practitioner might shift their values and understanding such that their habits and norms shift to create a new, sustainable way of being. The practitioner might demonstrate the competencies of implementing transformative change, modelling sustainable behaviour and wise decision-making. The competency of “empathy, mindfulness and social learning” implies critical reflection on one’s actions in comparison to their social context. Thus, reflection at this stage (tree branches and fruits) could create transformation that shifts one’s values and commitments (tree roots); the cyclical process could potentially begin again.

Practical implications

An adaptive and flexible framework of KSC could provide learning benefits by building the capacity for learners to think critically and tackle complex sustainability problems in novel ways (Brown, 2017; Glasser and Hirsh, 2016; Sterling et al., 2017; United Nations Educational, Scientific and Cultural Organization (UNESCO) 2017; Vare and Scott, 2007). Innovation and knowledge generation are possible since the KSC could teach “students how to think, rather than what to think, while letting [them] apply this thinking to real-world sustainability problems” (Wiek and Kay, 2015, p. 29). Through the KSC, people could also learn how to transform knowledge into action in their communities (Sterling et al., 2017, p. 160) and create real-world change. This is important, since unsustainable habits that comprise the “business-as-usual” case must be replaced with life-affirming actions and facilitate a new way of being in the world. After all, “[g]ood ideas with no ideas on how to implement them are wasted ideas” (Scott, 2013, p. 275).

Social implications

The authors have asserted that the implementation of the KSC could have social benefits because its associated pedagogies aim to actively involve learners in transforming society. The sequence sees the individuals’ reflecting upon and evaluating one’s growth vis-à-vis KSC and promotes the development of learning and other habits that betters ones’ competencies (Rieckmann, 2012). Such reflection and empathy are more likely to be inherent to people who contribute to their own learning about the need to be truly compassionate for each other and the planet (Glasser and Hirsh, 2016). In achieving this level of empathy, it is a relatively simple matter then to understand that technology and policy alone are not adequately able to facilitate large-scale and positive change; unsustainability is a problem created by human action and therefore must be counteracted with theories of and solutions to unsustainable behaviours. Integrating a responsive KSC tool into higher education could help build the capacities, capabilities, competencies and eventually mastery and habits of mind and body that give rise to sustainable well-being societies.

Originality/value

The authors summarize and critique the KSC literature with an eye to creating a flexible and adaptive tool for individuals to chart their own path towards being a sustainability practitioner. The conceptual work herein is the first of its kind, and it will assist program who wish to accentuate contextual factors and individual learning objectives into their design.

Details

International Journal of Sustainability in Higher Education, vol. 21 no. 3
Type: Research Article
ISSN: 1467-6370

Keywords

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