Design of multichannel nonrecursive digital filters with applications to seismic reflection data

Imperial Users onl

Maths instruction in vocational high school from teachers and students’ eyes: a different kettle of fish

Mathematics course in vocational high school education is significant worldwide to equip vocational students with the technical and personal skills that are required for the effective workforce as discussed in the context of Science, Technology, Engineering and Mathematics (STEM) education. The present research sets out to investigate 20 Turkish maths teachers’ belief and instructional practices through comparing vocational students’ perceptions for mathematics instruction and the researcher’s observation in a state vocational high school, which is under- researched. 20 maths teachers and 161 students participated in this longitudinal study (n=181). Mixed methods were used, and three types of data were collected as follows: questionnaires, interviews and observation for triangulation of data and methods t for the reliability and validity of the study. The findings indicated that maths teachers’ belief and practices were not consistent when compared with the questionnaire and interview data collected from vocational students, and also observation carried out by the researcher.Keywords: mathematics education, vocational high school, vocational students, beliefs and practice

Merely Folklore? The Role of a Growth Mindset in the Taking and Timing of Entrepreneurial Actions

Why do some potential entrepreneurs promptly engage in entrepreneurial behavior while others do not pursue their entrepreneurial intentions or delay acting? This study investigated whether potential entrepreneurs’ mindset shapes engaging in entrepreneurial behavior and the time until they do so. Over a 16-month period, holding more of a growth (vs. fixed) mindset positively predicted taking various entrepreneurial actions and doing so sooner. Interestingly, these effects vanished when individuals faced a less challenging context for entrepreneurship. Post-hoc exploratory analyses revealed that the COVID-19 pandemic magnified the impact of mindsets on entrepreneurial behavior. These findings pave the way for preliminary research on the viability of growth mindset interventions for fostering entrepreneurial behavior

Energy absorption in lattice structures in dynamics: Nonlinear FE simulations

An experimental study of the stress–strain behaviour of titanium alloy (Ti6Al4V) lattice structures across a range of loading rates has been reported in a previous paper [1]. The present work develops simple numerical models of re-entrant and diamond lattice structures, for the first time, to accurately reproduce quasi-static and Hopkinson Pressure Bar (HPB) test results presented in the previous paper. Following the development of lattice models using implicit and explicit non-linear finite element (FE) codes, the numerical models are first validated against the experimental results and then utilised to explore further the phenomena associated with impact, the failure modes and strain-rate sensitivity of these materials. We have found that experimental results can be captured with good accuracy by using relatively simple numerical models with beam elements. Numerical HPB simulations demonstrate that intrinsic strain rate dependence of Ti6Al4V is not sufficient to explain the emergent rate dependence of the re-entrant cube samples. There is also evidence that, whilst re-entrant cube specimens made up of multiple layers of unit cells are load rate sensitive, the mechanical properties of individual lattice structure cell layers are relatively insensitive to load rate. These results imply that a rate-independent load-deflection model of the unit cell layers could be used in a simple multi degree of freedom (MDoF) model to represent the impact behaviour of a multi-layer specimen and capture the microscopic rate dependence