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This paper aims to numerically solve fully developed laminar flow in trapezoidal ducts with rounded corners which result following forming processes.

A two-dimensional model for a trapezoidal duct with rounded corners is developed and conservation of momentum equation is solved. The flow is assumed to be steady, fully developed, laminar, isothermal and incompressible. The key flow characteristics including the Poiseuille number and the incremental pressure drop have been computed and tabulated for a wide range of: sidewall angle (θ); the ratio of the height of the duct to its smaller base (α); and the ratio of the fillet radius of the duct to its smaller base (β).

The results show that Poiseuille number decreases, and all the other dimensionless numbers increase with increasing the radii of the fillets of the duct; these effects were found to amplify with decreasing duct heights or increasing sidewall angles. The maximum axial velocity was shown to increase with increasing the radii of the fillets of the duct. For normally used ducts in hydrogen fuel cells, the impact of rounded corners cannot be overlooked for very low channel heights or very high sidewall angles.

The data generated in this study are highly valuable for engineers interested in estimating pressure drops in rounded trapezoidal ducts; these ducts have been increasingly used in hydrogen fuel cells where flow channels are stamped on thin metallic sheets.

Fully developed laminar flow in trapezoidal ducts with four rounded corners has been solved for the first time, allowing for more accurate estimation of pressure drop.

Introducing the concept of a design domain to truss topology optimization, this paper presents an algorithm generating geometrically admissible ground structures on possibly concave (or even disconnected) 3D design domains. That is a set of connections between nodal points actually respecting the geometry of the design domain. Since ground structures may be applied in other contexts the presentation does not assume any specifics of truss topology optimization. However, in the example section an application of ground structures in a truss topology optimization problem may be found.

The purpose of this article is to explore lesson and learning study as a form of ongoing teacher training which allows teachers the opportunity to reconstruct their practical thinking.

This document begins with a theoretical introduction in which the author explains the nature and dimensions of practical thinking, its importance for the professional development of teachers, followed by the lesson studies themselves, outlining the case of a teacher involved in a research group based on this type of ongoing training.

With the subtle differences and changes proposed for the Spanish context, lesson studies can be a valuable tool in terms of encouraging reflection and the critical questioning of personal values, beliefs and assumptions about teaching, whilst also enabling the reconstruction of teachers’ practical knowledge, in particular their hidden beliefs, habits and emotions.

This article offers a new approach for lesson studies as a method of training which can improve practice through the reconstruction of the practical thinking of those involved.

This paper aims to resolve the sizing issues of analog circuit design by using proposed metaheuristic optimization algorithm.

The hybridization of whale optimization algorithm and modified gray wolf optimization (WOA-mGWO) algorithm is proposed, and the same is applied for the automated design of analog circuits.

The proposed hybrid WOA-mGWO algorithm demonstrates better performance in terms of convergence rates and average fitness of the function after testing it with 23 classical benchmark functions. Moreover, a rigorous performance evaluation is done with 20 independent runs using Wilcoxon rank-sum test.

For evaluating the performance of the proposed algorithm, a conventional two-stage operational amplifier is considered. The aspect ratios calculated by simulating the algorithm in MATLAB are later used to design the operational amplifier in Cadence environment using 180nm CMOS standard process.

The hybrid WOA-mGWO algorithm is tailored to improve the exploration ability of the algorithm by combining the abilities of two metaheristic algorithms, i.e. whale optimization algorithm and modified gray wolf optimization algorithm. To build further credence and to prove its profound existence in the latest state of the art, a statistical study is also conducted over 20 independent runs, for the robustness of the proposed algorithm, resulting in best, mean and worst solutions for analog IC sizing problem. A comparison of the best solution with other significant sizing tools proving the efficiency of hybrid WOA-mGWO algorithm is also provided. Montecarlo simulation and corner analysis are also performed to validate the endurance of the design.

When detaining and enforcing treatment, psychiatric services often assumed that the person is separate from their dysfunctional biology and removed from their social context. Coproduction is hindered by polarised views where one party holds power and others are not able to promote their views. But if biomedical models are abandoned, ethical grounding for mental health law would be lost. The purpose of this paper is to explore the experience of detaining and being detained, clarifying understandings of trust, illness, personhood and control.

A hermeneutic phenomenological approach was employed.

A Social Worker and man who suffers from psychosis report that their choices are limited by mental health law. They both experience themselves as passive. The man rejects society and withdraws to avoid stress; while the Social Worker just follows legal guidelines. Interaction in mental healthcare is experienced as lacking trust, involving threat, but sometimes negotiation is possible. Control over illness is associated with having a choice of treatments. Psychosis is not experienced as a separate illness process and control is exercised over the person rather than that illness.

This was a small qualitative study designed to prompt discussion and inform further research and policy review.

To enable coproduction, detention or enforced treatment should be grounded more firmly in morality or criminal justice.

People who suffer psychosis could be understood and their views more often accepted.

An innovative research approach is used to bring new understanding.

Includes four outstanding essays from the Scottish Schools Essay Competition, illustrating how children see libraries and bookshops, and improvements they would like to see made. Demonstrates not only good creative writing, but an awareness, on the part of the young, of what is currently available and what could become available for the library/bookshop user. Includes some criticism and some praise, particularly with regard to the modern library.

An improved adaptive finite element analysis based on local error estimate is proposed via the element energy projection (EEP) technique. This paper aims to discuss the aforementioned idea.

The computational region for a posteriori error estimation based on EEP method is further confined to a critical set of local elements generated in the previous adaptive step, enhancing efficiency while maintaining accuracy. The adaptive procedure incorporated with hierarchical mesh refinement is then developed.

The effectiveness of the improved error estimation of the overall adaptive analysis is confirmed by several benchmark examples. The results show that the shrinkage of the local computational region has little negative influence on the accuracy of a posteriori error estimation, thus yielding an improved adaptive procedure with simplified logic and reduced cost.

By localizing the computational region for error estimation, two crucial but cumbersome tricks, i.e. treatments of virtual elements and hanging nodes, are removed, giving the proposed approach full clarity and flexibility. The improved adaptive procedure characterizes simpler and faster computational algorithm and can produce results with required accuracy measured in maximum norm.

This article, the first empirical study of its kind, presents findings from a larger qualitative study of principal mistreatment of teachers. A grounded theory method was used to study a sample of 50 US teachers who were subjected to long‐term mistreatment from school principals. The authors discuss descriptive, conceptual, and theoretical findings about principals’ actions that teachers define as mistreatment. In addition, the inductively derived model briefly looks at the harmful effects of principal mistreatment and abuse on teachers, psychologically/emotionally and physically/physiologically. Implications of study findings are discussed for administrator and teacher preparation, for school district offices, and for further research.