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Considers the problem of stability of the enhanced strain elements in the presence of large deformations. The standard orthogonality condition between the enhanced strains and constant stresses ensures satisfaction of the patch test and convergence of the method in case of linear elasticity. However, this does not hold in the case of large deformations. By analytic derivation of the element eigenvalues in large strain states additional orthogonality conditions can be derived, leading to a stable formulation, regardless of the magnitude of deformations. Proposes a new element based on a consistent formulation of the enhanced gradient with respect to new orthogonality conditions which it retains with four enhanced modes volumetric and shear locking free behaviour of the original formulation and does not exhibit hour‐glassing for large deformations.

As known from nearly incompressible elasticity, selective reduced integration (SRI) is a simple and effective method of overcoming the volumetric locking problem in 2D and 3D solid elements. This method of finite elastoviscoplasticity is discussed as are its well‐known limitations. In this context, an isochoric‐volumetric decoupled material behavior is assumed and thus the additive deviatoric‐volumetric decoupling of the consistent algorithmic moduli tensor is essential. By means of several numerical examples, the performance of elements using selective reduced integration is demonstrated and compared to the performance of other elements such as the enhanced assumed strain elements. It is shown that a minor modification, with little numerical effort, leads to rather robust element behaviour. The application of this process to so‐called solid‐shell elements for thin‐walled structures is also discussed.

This study aims to present a more accurate lifetime prediction model considering solder chemical composition.

Thermal cycling and standard creep tests as well as finite element simulation were used.

The study found lower error in the solder joint lifetime evaluation. The higher the Ag content is, the higher the lifetime is achieved.

It is confirmed.

The purpose of this paper is to investigate the application of the element‐free Galerkin (EFG) method to the simulation of metal forming processes and to propose a strategy to deal with volumetric locking problem in this context.

The J₂ elastoplastic material model, employed in the work, assumes a multiplicative decomposition of the deformation gradient into an elastic and a plastic part and incorporates a non‐linear isotropic hardening response. The constitutive model is written in terms of the rotated Kirchhoff stress and the logarithmic strain measure. A Total Lagrangian formulation of the problem is considered in order to improve the computational performance of the proposed algorithm. The imposition of the essential boundary conditions and also of the unilateral contact with friction condition are made by the application of the Augmented Lagrangian method. Here, aspects related to the volumetric locking are investigated and an F‐bar approach is applied.

The results show that the proposed approach presents no volumetric locking phenomenon when using the mean dilation approach. Moreover, differently from finite element approximations, no hour‐glass instabilities in the deformation pattern are observed, avoiding in this way the need to devise additional stabilization procedures in the proposed procedure.

This paper demonstrates the implementation and validation of the mean dilation approach, in the scope of the EFG, which was successful in coping with the volumetric locking phenomena and presented no hour‐glass instabilities in the problem cases considered in this work.

Investigates flexible working and how it affects workers — especially in the UK, where longer hours are worked than in continental Europe — though this is mostly put down to the fact that workers believe they must be seen at work to aid in furthering careers. Discloses that 30% of all approved requests for flexible working have been from managers, mostly at senior levels. Concludes managers will have to start trusting those who work away from the office, otherwise they will be unable to recruit and retain their best staff and competitors may be able to profit from that.

CONTROLLED EXPANSION has an important implication in the mechanical fastening of high performance structures. The technique provides that a cylindrical fastener expands plastically during installation to a slightly hour glass shaped cross section. Expansion is one to two per cent of the hole diameter at the shear plane, and three to five per cent at the surfaces. The result is a joint with remarkable integrity and attractive in cost saving potential. The advantages of controlled expansion are being incorporated into the fastening of the A300B wing structure after a critically thorough study of the systems described herein, in comparison with all proven and potential alternatives.

The study aims at exploring the perspective of three English as a Foreign Language teachers after their year-long involvement in the Lesson Study project in the context of Kazakhstan in order to capture and list any perceived changes in teachers’ educational beliefs over the period of the Lesson Study intervention. The main argument of the study suggests that the school-based Lesson Study initiative is conducive to triggering changes in teachers’ educational beliefs, and thus, might lead to positive changes in school culture in Kazakhstani schools. Shaped following Hill et al., (1982) in Swales, 1990 hour-glass model of a research project (Swales, 1990), the article reflects the third concluding part of the Ph.D. thesis focusing on the implementation of the Lesson Study methodology in Kazakhstan.

The study adopts the qualitative research design and follows the narrative inquiry methodology. The three narrative interviews (Bauer, 1996) are utilized as the main method of data collection. The data were analyzed as text following a general inductive approach (Thomas, 2003), where emerging themes were identified employing data reduction and further sub-categorized through the conceptual and theoretical lenses of the study. The emerged categories reflecting the perceived shifts in teachers’ educational beliefs were dialectically linked to implications for school culture in Kazakhstani schools.

As data suggest, the respondents’ active engagement in the Lesson Study professional learning community and exercising leadership through implementing changes in their classroom practice has made a positive impact on teachers’ rethinking their teaching practice, attitudes to students and their learning, collegiality, and professional self-identification. We conclude that, if organized properly, Lesson Study has enormous potential to facilitate changes of teachers’ educational beliefs: from direct transmission beliefs toward constructivist beliefs, from restricted professionals’ beliefs toward reflective practitioner beliefs and attitudes, toward beliefs in the power of student’s voice, and collaboration. Those shifts are linked to establishing a more positive, child-friendly and rights-based school culture with teachers’ shared visions and capacity for innovation.

We acknowledge that the abundance of the reported positive changes or perceived shifts in teachers’ thinking might not be the indicators of actual changes in their beliefs. We emphasize that the study was carried in a controlled context, i.e. the three ELF teachers were constantly supported, and the teacher talk was systematically guided by a trained facilitator. Warned by Giroux et al. (1999), we are aware of the major challenge of the fundamental assumption of critical pedagogy that teachers are willing and able to undertake “the practice of analyzing their practice” (p. 27) voluntarily. Thus, the question remains open: if the facilitator’s support is eliminated, will the results point to the occurrence of the disruption and disorientation as a necessary condition for the beliefs change?

Carried out in the largely overlooked by the academic literature context of the Reform at Scale (Wilson et al., 2013) in Kazakhstan and building on the original combination of conceptual and theoretical lenses, the research contributes to the academic literature by connecting teachers’ educational beliefs, Lesson Study and school culture. The findings might be of value for the school leaders, educators, teacher trainers, and policymakers to advocate Lesson Study as a systematic approach to the whole-school improvement, as a tool to facilitate positive changes in school culture, as well as give impetus to studies employing the school culture perspective in developing Lesson Study impact evaluation tools.

TO define the science of photo‐elasticity we need but say that, with the aid of certain optical equipment, it enables us to see the pattern of stress simultaneously over the entire extent of a scale model under test. If desired, the pattern may be seen in all the delicate hues of the spectrum, but for exact analytical measurement it is sometimes preferable to obtain the sharp‐edged black and white tracing by means of monochromatic light. We might with reason add that the pattern so depicted is complete down to the last detail and represents, in many cases, a unique solution of a complex mathematical problem in elastic deformation. Its application to mechanical engineering design has been widespread and is still reaching out into new fields. By its use it is now possible to trace and measure the intensity and internal distribution of stress in loaded components far more speedily and accurately than can be achieved by any other method.

The nature of retailing in Singapore has changed significantly over the past three decades, reflecting the growing affluence of the population and the influx of tourists, particularly those from Japan. A major influence in these changes has been the Government which has arranged for the development of planned shopping centres in both the central area and the suburban new towns. However, in the 1990s a further wave of change is coming: the nature of retailing is changing as a result of an economic downturn and the growing number of foreign retailers operating on the island. In addition, the Government has decided to shake up the small shop sector and to allow major retail developments in the suburban areas. The net result is likely to be a further period of upheaval and it is by no means certain that Singaporean retailers are going to be winners this time.

A finite element procedure is presented for refined transient analysis of two‐dimensional (plane or axisymmetric) non‐linear structures involving arbitrarily large displacements, rotations and strains. The finite element model is based on the biquadratic nine‐node element of the Lagrange family. The relevant points pertaining to the equations of motion and their integration and to the spatial description, including geometrical and material non‐linearities, are considered. In particular, stress and strain rates are discussed. Finally, significant numerical applications show the effectiveness of the proposed method.