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The purpose of this article is to debut a novel initiative that could potentially optimize resources that are currently constrained but, if unleashed, could help ameliorate the science, technology, engineering and mathematics teacher shortage. The initiative involves the reconceptualization of the National Network for Educational Renewal (NNER) tripartite model, which evolved from the work of Goodlad (1994a) and promotes cooperation and partnerships between the three important players responsible for preparing succeeding generations of competent teachers: PK-12 schools, university colleges of education and university colleges of arts and sciences (Roselle, Hands, Marino, Kilgallen, & Howard, 2021; Goodlad, 1994a).

The approach used in writing the article was narrative, offering a brief review of the various challenges that have had an impact on the national teacher shortage, particularly in the field of mathematics.

The study suggests that a reconceptualized NNER tripartite model can be implemented to assuage the devastating effects of the coronavirus disease 2019 pandemic on learning, offer support to an overworked teacher workforce and provide a possible math teacher recruitment pipeline by forming a life-giving partnership between a college of education, a college of arts and sciences, a local elementary school and undergraduate math club members.

This is an original application of the NNER tripartite model, particularly with math teacher recruitment in mind, and it is hoped that the model will be considered transferable to a variety of school-university contexts. However, additional study is required to explore the validity and replicability of this model.

The horizontal rotational single-sheet tester (RSST) suffers from weaknesses such as the reduced size of test samples, measurement disturbances due to magnetic flux leakage and nonhomogeneity of field in the measurement area. Although the vertical RSST allows to overcome the first two aforementioned drawbacks, the heterogeneity of the field in the test sample remains an issue. In addition, there is still a lack of device standardization to ensure test repeatability, as already is well established with the Epstein frame. This paper aims to investigate the influence of several parameters on the field homogeneity in the test sample.

A fully 3D finite element model of a vertical RSST is developed and used to perform a sensibility study on several geometrical parameters.

The influence of several parameters on the field homogeneity in the test sample, such as the geometrical dimensions of the yokes, the presence or not of holes drilled inside the test sample for B-coil placement as well as the size of the H-coils and B-coils, is addressed.

It is expected that this study will contribute to the optimization and standardization vertical RSSTs.

The fire resistance of wooden structures is commonly based on the calculation or measurement of the char layer. Designers usually estimate the char layer at the surface of a structural element by using analytical models. Some of these charring models can be found in regulations, as Eurocode 5. These analytical models, quite simple to use, are only reliable for the standard fire curve. In that case, the design of the structure is qualified as “prescriptive-based design” and can lead to oversizing the structure. Optimization of a structure can be achieved by using a “Performance-based design”, where realistic fire scenarios are taken into account by means of more or less complex models [parametric fires, two-zones models, computational fluid dynamics (CFD)]. For these so-called “natural fires”, no model for charring is available. The purpose of this paper is to present a novel methodology for applying a performance-based design to a simple timber structure.

This paper presents the development of a numerical model aiming to simulate the thermal transfer and charring in wood, under any type of thermal exposure, including non-standard fire curves. After presenting the physical background, the model is calibrated and compared to existing experimental studies on wood samples exposed to different fire curves. The model is then used as a tool for assessing the fire resistance of a common wooden structure exposed to standard and non-standard fire curves.

The results show that the fire resistance is obviously dependent on the choice of the thermal exposure. The reliability of the model is also discussed and the importance of taking into account particular reactions in wood during heating is underlined.

One aim of this paper is to show the opportunity to apply a performance-based approach when designing a wooden structure. It shows that more knowledge of the material behaviour under non-standard fires is still needed, especially during the decay phase.

This study aims to explore the overlap between symptoms of depression, anxiety, irritability and aggressiveness in autism spectrum disorder (ASD), to measure specific and idiosyncratic emotional responses.

A total of 42 high functioning adolescents and adults, between 12 and 39 years old, meeting the diagnostic and statistical manual of mental disorders – 5 criteria for ASD were selected from the InFoR Autism cohort. Data were analyzed in an exploratory way using Hill and Smith and K-medoids cluster analysis.

The authors found an aggregation of anxiety, depression, aggressive behaviors and irritability. Cluster analysis was maximized for two groups with 17 and 25 participants, respectively. The first group was characterized by high levels of symptoms of irritability, aggressiveness, hyperactivity and intermediate levels of anxiety and depression. In the first group, participants had significantly higher levels of autistic symptoms considering the social responsiveness scale and repetitive behavior scale-revised scales (relatives’ reports) suggesting that a particular group of subjects with a high level of ASD specific symptoms may express anxiety and depression in a specific way based on externalizing behaviors in addition to the common mood and anxiety symptoms.

Improved understanding of the aggregation of externalized symptoms with symptoms of anxiety and mood disorders in ASD should lead to a better understanding of the underlying mechanisms related to emotion dysregulation in ASD.

Improved knowledge of the symptoms could lead to enhanced detection of psychiatric comorbidities in ASD.

The study was based on a transdiagnostic approach of psychiatric symptoms in individuals with ASD. Aggregation and clustering analysis was used to explore naive patterns of these psychiatric symptoms.

For the proposed coupling transformer, a magnetic bypass based on the virtual air gap principle is realized by inserting auxiliary windings in a return leg added to a standard transformer. With such a setup, it is able to act as a voltage regulator as well as protect the power electronics of the dynamic voltage restorer from electrical grid fault currents. This paper focuses on the electrical design part of the coupling transformer. It aims to explain how the behavior of the auxiliary windings electrical circuit of the magnetic bypass impacts the performances of the device.

The influence of the electrical auxiliary windings circuit configurations on the operation of the coupling transformer is studied by finite element analyses with nonlinear and isotropic magnetic materials.

A configuration for the realization of the electrical circuit of the auxiliary windings is determined according to the finite element simulation results to achieve the design of the coupling transformer whose magnetic core was previously designed.

By studying the operation of a special coupling transformer with nonlinear saturation phenomenon by finite element analyses, a to-do list of the electrical circuit parameters is described to design this device well.

This paper aims to deal with a performance comparison of an 8/6 radial-flux switched reluctance machine (RFSRM) and an axial-flux switched reluctance machine (AFSRM), presenting equivalent active surfaces.

An axial machine was designed based on the equivalent active surfaces of a radial one. After estimating the machine inductances with a reluctance network, finite elements numerical models have been implemented for a more precise inductance determination and to estimate the electromagnetic torque for both machines. Finally, the AFSRM was thoroughly examined by analyzing the impact of some geometric parameters on its performance.

The comparison of the RFSRM and AFSRM at equivalent active surfaces showed that the obtained axial machine is more compact along with an improvement in the electromagnetic torque.

The equivalent AFSRM is more compact, therefore more interesting for transport and on-board applications.

The RFSRM and AFSRM performance comparison using the same active surfaces has not been done. Moreover, the AFSRM presented has a rare design with no rotor yoke and where the rotor teeth are encapsulated in a nonmagnetic structure, allowing a more compact design.

The purpose of this study is to determine the steady state of an electromagnetic structure using the finite element method (FEM) without calculation of the transient state. The proposed method permits to reduce the computation time if the transient state is important.

In the case of coupling magnetic and electric circuit equations to obtain the steady state with periodic conditions, an approach can be to discretise the time with periodic conditions and to solve the equation system. Unfortunately, the computation time can be prohibitive. In this paper, the authors proposed to use the waveform relaxation method associated with the Newton method to accelerate the convergence.

The obtained results show that the proposed approach is efficient if the transient state is important. On the contrary, if the transient state is very low, it is preferable to use the classical approach, namely, the time-stepping FEM.

The main limitation of the proposed approach is the necessity to evaluate or to know the time constant and consequently the duration of the transient state. Moreover the method requires some important memory resources.

In the context of the use of the time-stepping FEM, one of the problems is the computation time which can be important to obtain the steady state. The proposed method permits avoidance of this difficulty and directly gives the steady state.

The proposed approach will permit to model and study the electromagnetic systems in the steady state, and particularly the transformers. Because of the gain in computing time, the use of optimisation techniques will be facilitated.

The novelty of this study is the proposal of the waveform relaxation–Newton method to directly obtain the steady state when applied to the three-phase transformer.

The purpose of this paper is to propose a new framework based on linear control system theory and the use of proportional (P) controller and proportional integral (PI) controller to address identified stability issues and control the time properties in hybrid fire testing.

The paper approaches hybrid fire testing as a control problem. It establishes the state equation to give the general stability conditions. Then, it shows how P and PI controllers can be incorporated in the system to maintain stability. A virtual hybrid fire testing is performed on a 2D steel frame for validation and to compare the performance of the controllers.

Control system theory provides an efficient framework for hybrid fire testing and rigorously formulate the stability conditions of the system. The use of a P-controller stabilises the process, but this controller is not suitable for continuous change of stiffness of the substructures. In contrast, a PI-controller handle the stiffness changes. The results of a virtual hybrid fire testing of a 2D steel frame shows that the PI-controller succeeds in reproducing the global behaviour of the frame, even if the surrounding structure is non-linear and subjected to fire.

The paper provides a rigorous formulation of the general problem of hybrid fire testing and shows the interest of a PI controller to control the process under varying stiffness. This methodology is a step forward for hybrid fire testing because it allows capturing the global behaviour of a structure, including where the numerical substructure behaves nonlinearly and is subjected to fire.

In this paper the authors review the recent numerical techniques proposed to solve the forward and inverse problems concerning the electromagnetic casting and electromagnetic levitation techniques of the metallurgical industry. In addition, the authors present a new topology optimization method to solve the inverse axisymmetric electromagnetic levitation problem.

The proposed method is based on an exact second-order topological expansion of a Kohn–Vogelius-like functional specially devised for this problem.

Through some examples the authors show that it can find suitable solutions efficiently.

The new method completes the set of efficient methods available to solve the inverse electromagnetic casting and the inverse axisymmetric electromagnetic levitation problems.