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In this work, with a goal to ultimately forward the advancement of additive manufacturing research, the author applies the Wheeler-Boettinger-McFadden model through a progressive series of increasingly complex solidification problems illustrating the evolution of both dendritic as well as columnar growth morphologies. For purposes of convenience, the author assumes idyllic solutions (i.e. the excess energies associated with mixing solid and liquid phases can be neglected).

In this work, the author applied the phase-field model through a progressive series of increasingly complex solidification problems, illustrating the evolution of both dendritic as well as columnar growth morphologies. Beginning with a non-isothermal treatment of pure Ni, the author further examined the isothermal and directional solidification of Cu–Ni binary alloys.

(1) Consistent with previous simulation results, solidification simulations from each of the three cases revealed the presence of parabolic, dendrite tips evolving along directions of maximum interface energy. (2) For pure Ni simulations, changes in the anisotropy and noise magnitudes resulted in an increase of secondary dendritic branches and changes in the direction of propagation. The overall shape of the primary structure tended also to elongate with increased anisotropy. (3) For simulations of isothermal solidification of Ni–Cu binary alloys, the development of primary and secondary dendrite arm formation followed similar patterns associated with a pure substance. Calculations of dendrite tip velocity tended to increase monotonically with increasing anisotropy in accordance with previous research. (4) Simulations of directional solidification of Ni–Cu binary alloys with a linear temperature profile demonstrated the presence of cellular dendrites with relatively weak side-branching. The occurrence of solute trapping was also apparent between the primary dendrite columns. Dendrite tip velocities increased with increasing cooling rate.

This research, particularly the section devoted to directional solidification of binary alloys, describes a novel numerical framework and platform for the parametric analysis of various microstructural related quantities, including the effects due to changes in temperature gradient and cooling rate. Both the evolution of the phase and concentration are resolved.

Hillyard argues that Irving Goffman’s mixing of detailed study, an evocative writing style and interjection as social commentator can legitimately be defined as social science research because it highlights inequalities. His approach is seen not as a systematic model but as a appreciation of the rhetorical nature of ethnographic writing and argument, whilst maintaining a critical theoretical agenda. Debates over the legitimacy of partisan research and in particular critical ethnography are a feature of the last decade in education (Hammersley, 1992) and Irving Goffman, in particular, is held in high esteem for his work on inequalities which is why the debate at the Oxford 2002 conference was so pertinent.

The rise of a performativity discourse in education in England emanates from the importation of an economic ‘market’ structure for schools in order to improve the effectiveness and efficiency of the outputs of learning and to increase the opportunity of choice for the ‘consumers’ of education (Ball, 1998). Institutions focus their policies and practice, on improving performance and survival to maintain and develop their market share. This is due to the competitive nature of a market structure. The performativity criterion of efficiency and effectiveness is an optimisation of the relationship between input and output (Lyotard, 1979). In the case of education this means both ensuring a favourable qualitative award from a national inspection service and raising the achievement levels of pupils in national tests to ensure a high position in published tables of educational performance. High ratings on these two performativity indicators improve a school’s attraction to parents and students in the educational market place. This results in improved resources, increasing the opportunity for the school to be more selective about the students it accepts and the quality of the teachers it employs.

The purpose of this paper is to examine how a middle school science teacher, new to programming, supports students in learning to debug physical computing systems consisting of programmable sensors and data displays.

This case study draws on data collected during an inquiry-oriented instructional unit in which students learn to collect, display and interpret data from their surrounding environment by wiring and programming a physical computing system. Using interaction analysis, the authors analyzed video recordings of one teacher’s (Gabrielle) pedagogical moves as she supported students in debugging their systems as they drew upon a variety of embodied, material and social resources.

This study presents Gabrielle’s debugging interactional grammar, highlighting the pedagogical possibilities for supporting students in systematic ways, providing affective support (e.g. showing them care and encouragement) and positioning herself as a learner with the students. Gabrielle’s practice, and therefore her pedagogy, has the potential to support students in becoming better debuggers on their own in the future.

While much of the prior work on learning to debug focuses on learner actions and possible errors, this case focuses on an educator’s debugging pedagogy centered on the educator debugging with the learners. This case study illustrates the need for educators to exhibit deft facilitation, vulnerability and orchestration skills to support student development of their own process for and agency in debugging.

Over the twentieth century, there was a wide range of demographic changes in the family. Demographic shifts included a decline in the number of first marriages, and a rise in the divorce rate, the number of births outside marriage and the number of one parent families. Whilst ideologies (Eatwell, 1993; Seliger, 1976) of the family are many and varied, they tend to privilege the intact nuclear family as the natural, ideal and normal family form (Jagger & Wright, 1999) and as patriarchal, white and middle class. Other family structures, in contrast, can be seen as deviations from the norm. Such ideologies of the family are at odds with the changes in family structure outlined above. This tension between the ideal and the real can help stereotype children who live in families which deviate from the perceived norm of the intact nuclear family. This can disadvantage children who may be otherwise well-adjusted (Ferri, 1976; Mitchell, 1985).

This ESRC‐based research article aims to investigate the effects of performativity on primary schools and the teachers therein. It also aims to show how performativity to maintain and improve the school's position in an educational market affects the teacher relations with their institution and how the school works to embrace its teachers in developing the school's market position.

Four researchers carried out this ESRC (RES‐000‐23‐1281) research, to a greater or lesser extent. The researchers in all of the schools, except City, carried out interview/conversations in the main, with observational field notes accounting for just over 50 per cent of their total data. They then began progressive focusing on City school where the rest of the observational field notes were carried out and in particular the bulk of conversations with young learners. This focus also included the largest group of teacher interview/conversations. This progressive focusing bears the weight of the ethnographic data and the analysis for this article, in line with a grounded theory approach. The whole database included 52 days’ observational field notes, 54 recorded conversations with teachers and other significant adults, and 32 recorded conversations with learners. All recorded conversations with management, teachers, pupils and parents that were seen as being of theoretical significance were transcribed.

The paper outlines some of the similarities with these institutions, but also shows how this new model differs and how it could be applied to a much wider constituency than the earlier three models – that of the public and private sector. It shows how the embracing performative institution in a marketised environment influences the practices of its teachers and changes to their professional commitment, which focuses more on the institutional development than broader professional values. At the same time it can be seen how supportive professional cultures encourage teachers to embrace the school's performative development and how this influences teacher identity. The findings suggest that institutional members both constitute, and are constituted by, the influence of the embracing institution and performative regulation and that their professional identities are constantly readjusted to ensure their interests coincide with the institutions interests.

This article provides useful formation on how performativity to maintain and improve the school's position in an educational market affects the teacher relations with their institution and how the school works to embrace its teachers in developing the school's market position.

It was a typical Wednesday in Room 4. Wednesday mornings meant time for Invitations. A time cherished and enjoyed by the intermediate students in Ruth’s elementary classroom. Invitations were a time for small groups of students to work together across disciplines on self-selected topics offered by the teacher but grown from student interests. On a weekly basis students signed up for Invitations – sometimes sticking with a topic for several weeks and sometimes attending to a new topic each week. Topics ranged anywhere from using technology, taking apart CD players to discover how they work, exploring media coverage of current events, debating social issues, dissecting plants, to making maps. Students then worked cooperatively in student-facilitated groups to use multiple ways of knowing, and available resources and materials to ask important questions, to investigate issues of significance, to pursue possibilities, and to inquire with others.