Research has now demonstrated that students can learn nature of science concepts variously through student‐led investigations, contemporary cases, and historical cases. Here we articulate more precisely the merits, deficits, and context of each approach and begin to profile how to integrate them as complementary methods. Emphasis now needs to shift to the needs of practicing teachers and the detailed strategies and modes of assessment that make each method effective and manageable in a classroom and institutional context.

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Purpose During design of reconfigurable manufacturing systems, manufacturing companies need to select and implement the right enablers of reconfigurability in accordance with the specific requirements being present in the manufacturing setting. Therefore, the purpose of this paper is to investigate enablers of reconfigurability in terms of their importance in industry, current level of implementation in industry, and significant differences in their implementation and criticality across different manufacturing settings. Design/methodology/approach A questionnaire survey is conducted, in order to provide generalizable empirical evidence across various industries and manufacturing types. Findings The findings indicate that the level of implementation of the reconfigurability enablers is rudimentary, while their criticality is perceived higher than the current level of implementation. Moreover, significant differences regarding implementation and criticality of mobility, scalability, and convertibility were found for companies with varying degrees of manual work, make-to-stock production, and varying production volume, industry type and organization size. Research limitations/implications Main limitations of the research cover the relatively small sample size and non-random sampling method applied, primarily limited to one country, which could be increased to further extent the findings reported in this paper. Practical implications The findings indicate that the importance and implementation of reconfigurability enablers is contingent on the manufacturing setting. Thus, the research presented in this paper provides valuable knowledge in regard to aiding a paradigm shift in industry and help companies design manufacturing systems with the right reconfigurability enablers. Originality/value This paper expands research on manufacturing system design for changeability and reconfigurability, by explicitly considering these as capabilities that can be enabled in various ways for various purposes in different manufacturing contexts.

Reconfigurable manufacturing has been widely labelled the manufacturing paradigm of the future, due to its ability to rapidly and costefficiently respond to changing market conditions. Manufacturing reconfigurability can be dealt with at various levels of the factory, and includes multiple design and operational issues related to both physical and logical reconfigurations. The purpose of this paper is to review state-of-the-art literature on reconfigurable manufacturing and provide an overview of the current body of research, by assessing which structuring levels of the factory and corresponding research issues that are dealt with. Conclusively, currently unexplored areas and interesting issues that could be addressed in future research are identified.

The problems in the evaluation of children with suspected infravesical obstruction are shortly reviewed. Based upon literature studies it is concluded, that an isolated urinary flow measurement determining the Qmax is a suitable procedure of screening. Due to different shortcomings of earlier published normal materials, we investigated the spontaneous urination of 205 normal children aged 3 to 13 years in their normal environment. The mictiograph was installed in the toilet of two kindergartens and one school, enabling the children freely to void into the machine upon desire. From the flow curves the following parameters were calculated: Q1 sec, Qmax, Qmax time, and the micturition time, all of them being related to the square root of the voided volume. The data were non-parametrically statistically processed, and the limits of normal values (2 1/2% and 97 1/2% percentiles) are defined for different groups of age and sex. Furthermore, the different flow curve patterns are described, and it is found, that in 90% of the cases they are identical to the adult pattern.

Context. With the advent of space-based asteroseismology, determining accurate properties of red-giant stars using their observed oscillations has become the focus of many investigations due to their implications in a variety of fields in astrophysics. Stellar models are fundamental in predicting quantities such as stellar age, and their reliability critically depends on the numerical implementation of the physics at play in this evolutionary phase. Aims. We introduce the Aarhus red giants challenge, a series of detailed comparisons between widely used stellar evolution and oscillation codes that aim to establish the minimum level of uncertainties in properties of red giants arising solely from numerical implementations. We present the first set of results focusing on stellar evolution tracks and structures in the red-giant-branch (RGB) phase. Methods. Using nine state-of-the-art stellar evolution codes, we defined a set of input physics and physical constants for our calculations and calibrated the convective efficiency to a specific point on the main sequence. We produced evolutionary tracks and stellar structure models at a fixed radius along the red-giant branch for masses of 1.0 M⊙, 1.5 M⊙, 2.0 M⊙, and 2.5 M⊙, and compared the predicted stellar properties. Results. Once models have been calibrated on the main sequence, we find a residual spread in the predicted effective temperatures across all codes of ∼20 K at solar radius and ∼30–40 K in the RGB regardless of the considered stellar mass. The predicted ages show variations of 2–5% (increasing with stellar mass), which we attribute to differences in the numerical implementation of energy generation. The luminosity of the RGB-bump shows a spread of about 10% for the considered codes, which translates into magnitude differences of ∼0.1 mag in the optical V-band. We also compare the predicted [C/N] abundance ratio and find a spread of 0.1 dex or more for all considered masses. Conclusions. Our comparisons show that differences at the level of a few percent still remain in evolutionary calculations of red giants branch stars despite the use of the same input physics. These are mostly due to differences in the energy generation routines and interpolation across opacities, and they call for further investigation on these matters in the context of using properties of red giants as benchmarks for astrophysical studies.

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