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This paper aims to examine how two White teachers, experienced and award-winning veteran educators, navigated issues of race, class and privilege in their instruction, and ways that their efforts and shortcomings shaped both teacher agency and classroom spaces.

This study’s methodology centers participants’ experiences and understandings over the course of two years of interviews, classroom observations and discussion groups. The study is conceptually informed by Sara Ahmed’s argument that social justice is often approached as something that education “can do,” which is problematic because it assumes that successful enactment is “intrinsic to the term.” Discussing and/or intending social justice replaces real change, and those leading the conversations believe that they have made meaningful differences. Instead, true shifts in thinking and action are “dependent on forms of institutional commitment […and] how it [diversity/social justice] gets taken up” (p. 241).

Using an in vivo coding approach – i.e. using direct quotations of participants’ words to name the new codes – the authors organized their findings into two discussions: “Damn – Every Time I’m with the Kids, I Just End Up Feeling Frozen”; and “Maybe I’m Just Not Giving These Kids a Fair Shake – Maybe I’m the Problem”.

The participants centered a participatory examination of intersectionality, rather than the previous teacher-mandated one. They “put into action” -xplorations of intersectionality that were predicated on students’ identities and experiences, thus making intersectionality a lived concept, rather than an intellectual one, and transforming students’ and their own engagement.

Buckling should be carefully considered in steel assemblies with members subjected to compressive stresses, such as bracing systems and truss structures, in which angles and built-up steel sections are widely employed. These type of steel members are affected by torsional and flexural-torsional buckling, but the European (EN 1993-1-2) and the American (AISC 360-16) design norms do not explicitly treat these phenomena in fire situation. In this work, improved buckling curves based on the EN 1993-1-2 were extended by exploiting a previous work of the authors. Moreover, new buckling curves of AISC 360-16 were proposed.

The buckling curves provided in the norms and the proposed ones were compared with the results of numerical investigation. Compressed angles, tee and cruciform steel members at elevated temperature were studied. More than 41,000 GMNIA analyses were performed on profiles with different lengths with sections of class 1 to 3, and they were subjected to five uniform temperature distributions (400–800 C) and with three steel grades (S235, S275, S355).

It was observed that the actual buckling curves provide unconservative or overconservative predictions for various range of slenderness of practical interest. The proposed curves allow for safer and more accurate predictions, as confirmed by statistical investigation.

This paper provides new design buckling curves for torsional and flexural-torsional buckling at elevated temperature since there is a lack of studies in the field and the design standards do not appropriately consider these phenomena.

The purpose of this work is to optimize the monitoring of vibrations on dynamometric test rigs for railway brakes. This is a quite demanding application considering the continuous increase of performances of high-speed trains that involve higher testing specifications for brake pads and disks.

In this work, authors propose a mixed approach in which relatively simple finite element models are used to support the optimization of a diagnostic system that is used to monitor vibration levels and rotor-dynamical behavior of the machine. The model is calibrated with experimental data recorded on the same rig that must be identified and monitored. The whole process is optimized to not interfere with normal operations of the rig, using common inertial sensor and tools and are available as standard instrumentation for this kind of applications. So at the end all the calibration activities can be performed normally without interrupting the activities of the rig introducing additional costs due to system unavailability.

Proposed approach was able to identify in a very simple and fast way the vibrational behavior of the investigated rig, also giving precious information concerning the anisotropic behavior of supports and their damping. All these data are quite difficult to be found in technical literature because they are quite sensitive to assembly tolerances and to many other factors. Dynamometric test rigs are an important application widely diffused for both road and rail vehicles. Also proposed procedure can be easily extended and generalized to a wide value of machine with horizontal rotors.

Most of the studies in literature are referred to electrical motors or turbomachines operating with relatively slow transients and constant inertial properties. For investigated machines both these conditions are not verified, making the proposed application quite unusual and original with respect to current application. At the same time, there is a wide variety of special machines that are usually marginally covered by standard testing methodologies to which the proposed approach can be successfully extended.

This paper aims to perform an analytical analysis on portfolio allocation when a tracking error volatility (TEV) constraint holds, drawing specific attention to the portfolio efficiency issue. Indeed, it is well known that investors can assign part of their funds to asset managers who are given the task of beating a benchmark portfolio. However, the risk management office often imposes a TEV constraint to the asset managers’ activity to maintain the portfolio risk near to the risk of the benchmark. This situation could lead asset managers to select non efficient portfolios in the total return and absolute risk perspective. However, the risk management office can impose further constraints, such as on maximum variance or maximum value at risk (VaR) to maintain the overall portfolio risk under control.

First the authors define the TEV constrained-efficient frontier (ECTF), a set of TEV constrained portfolios that are mean–variance efficient. Second, they define two new portfolio frontiers analyzing how the imposition of a maximum variance or maximum VaR restriction can reduce the ECTF. Third, they investigate the feasibility of such portfolio frontiers and their relationships.

The authors find that variance or VaR constraint can force asset managers to pursue portfolio efficiency.

This is a practically important issue given that asset managers often receive a constraint on TEV from the risk management office, but the risk management office does not ask them to minimize the TEV as often assumed in the optimizations performed in the literature on this topic.

The purpose of this paper is to describe the development of a robot for surveillance able to move in structured and unstructured environments and able to overcome obstacles with high energetic efficiency.

The proposed Epi.q‐TG hybrid robot combines wheeled and legged locomotion. It is equipped with four three‐wheeled locomotion units; traction is generated by the two forecarriage units, while the two rear ones have same geometry but are idle. Each front unit is actuated by a single motor with the interposition of an epicyclical gearing, accurately designed in order to suitably switch between wheeled and legged motion. The robot changes locomotion mode from rolling on wheels (advancing mode) to stepping on legs (automatic climbing mode) according to local friction and dynamic conditions.

The experimental results confirm the design objectives. In advancing mode, the robot behaves like a four‐wheeled vehicle, with high speed and energetic efficiency. In automatic climbing mode, the robot can walk on uneven and soft terrains and overcome steps with remarkable height with respect to its dimensions (up to 84 per cent of the locomotion unit height).

Besides surveillance, Epi.q‐TG can be successfully used in many tasks in which it is useful to combine the advantages of wheeled and legged locomotion, e.g. unmanned inspection of nuclear and chemical sites, minesweeping, and intervention in disaster zones.

The core of the project is the epicyclical mechanism of the locomotion unit, which switches between advancing mode and automatic climbing mode without control action. This solution limits the control and actuation complexity and consequently the robot cost, widening the range of possible applications.

The aim of the research is the development of a small-scale ground mobile robot for surveillance and inspection; the main design goals are mobility in indoor environments with step climbing ability, pivoting around a vertical axis and without oscillations for stable vision, mobility in unstructured environments, low mechanical and control complexity.

The proposed hybrid leg-wheel robot is characterized by a main body equipped with two actuated wheels and two praying Mantis rotating legs; a rear frame with two idle wheels is connected to the main body by a vertical revolute joint for steering; a second revolute joint allows the rear axle to roll. The geometrical synthesis of the robot has been performed using a nondimensional approach for generality's sake.

The experimental campaign on the first prototype confirms the fulfilment of the design objectives; the robot can efficiently walk in unstructured environments realizing a mixed wheeled-legged locomotion.

Thanks to the operative flexibility of Mantis in indoor and outdoor environments, the range of potential applications is wide: surveillance, inspection, monitoring of dangerous locations, intervention in case of terroristic attacks, military tasks.

Different from other robots of similar size, Mantis combines high speed and energetic efficiency, stable vision, capability of climbing over high steps, obstacles and unevenness.

The purpose of this paper is to present a cost‐effective design for a new rescue robot locomotion module using the principle of a continuous sliding membrane to achieve propulsion ratio (PR) near 1. Such high PR cannot be reached by other locomotion mechanisms that have been proposed.

The paper first introduces the PR as a reference parameter to assess locomotion effectiveness of snake‐ and worm‐like robots. The state‐of‐the‐art is reviewed. A direction to step beyond getting PR near 1 is indicated. The way is by realizing a continuous sliding membrane. Two solutions in this direction which have been recently proposed are recalled. It is shown that none of them can be practically implemented to realize functioning systems with today's available technology. A new design with membrane actuation has been identified and it is described in detail. A prototype has been realized and earliest results and evidence of functioning described.

Critical discussion of the concept of locomotion based on a sliding membrane was conducted. A new design for a robot locomotion module applying this concept was presented. Earliest evidence of functioning and effectiveness of the new system proposed was given.

A new locomotion principle is shown. The state‐of‐the‐art background is discussed. A design to realize the new system in a cost‐effective way is described. The research implications lie in the future development of new mobile robots with higher locomotion capability than today's available systems. Several future research and development directions are shown.

A new generation of more locomotion‐effective snake‐ and worm‐robots, especially for rescue application in rubble, is foreseen. The design proposed takes cost‐effectiveness and practical realizability into account.

The continuous sliding membrane concept had been already proposed but no reasonable realization and actuation solutions had been singled out. The design of the new locomotion system is totally new and contains several breakthrough ideas. A prototype is available proving worthy in concept and functioning. It is cost‐effective and this will allow shorter application to real robots.

This paper assesses the impact of this program on the rural women's employment opportunities using data from the 2015 round of the household's living standard survey (HLSS) of Côte d'Ivoire.

In 2013, in order to improve the living conditions of the rural population, the Ivorian government launched the National Program for rural electrification (PRONER) to electrify all localities with more than 500 inhabitants.

The results show that PRONER, while reducing the time allocated to performing household chores, increases women's employment through the reallocation of time to full-time paid work in the agricultural and non-agricultural sectors. The authors also find that the allocation of men's time is not affected by this programme. A possible mechanism that would explain such a pro-women effect is the labour-saving technology introduced to home production as an effect of the reform.

As a limitation, it is important to note that these results were obtained in the specific context of PRONER in Côte d’Ivoire and are not necessarily applicable to rural electrification programmes in other contexts. Furthermore, the choice of other indicators to measure women's empowerment is limited by the quality of the data available. It would be interesting for future research to extend this analysis to include other aspects of women's empowerment and household welfare.

This paper is the first to the author’s knowledge to apply a robust econometric method by combining an inverse probability weighted regression adjustment model with Heckman sample selection method to access a robust causal effect of the PRONER in Côte d'Ivoire.

The link between mergers and acquisitions (M&A) and innovation has been analysed in both corporate finance studies and the innovation literature. Despite this attention and the practical evidence that highlights different connections between these two terms, there is a need to investigate the latest trends with regard to these important topics, and to put a particular focus on the emerging paradigm of open innovation. Thus, this paper aims to provide a systematic literature review (SLR) about the relationship between M&As and the concept of innovation in the current scenario.

Through an SLR from 2012 to June 2017, 55 papers have been identified and analysed to give a better understanding of the motivations and the methodologies adopted in past studies.

This paper identifies various conceptual and research methodological characteristics of studies that have connected, directly or indirectly, M&As and innovation in recent years. In addition, the results highlight a scarcity of studies that explicitly or implicitly refer to the open innovation paradigm, marking only a partial understanding of this emerging phenomenon.

This paper improves the knowledge on the link between extraordinary corporate transactions and innovation, and it highlights that a clear consensus, particularly regarding the open innovation paradigm, is lacking. Thus the authors propose that future studies should carefully evaluate M&As by following the open innovation approach.

A synopsis is presented of the numerical finite element methodology currently in use at the Institute for Computer Applications (ICA) for the simulation of industrial forming processes. The development of the method is based on the inelastic properties of the material with an extension towards the inclusion of elastic effects and accounts for the thermal phenomena occurring in the course of the deformation. An essential constituent of the computational procedure is the treatment of the unsteady contact developing between the workpiece material and the tool during forming, and of the associated friction phenomena. Automatic mesh generation and variable discretization adaptable to the development of the numerical solution are of importance for industrial applications. These aspects are presented and discussed. Furthermore, solution techniques for thermomechanically coupled problems are considered and investigated with respect to their numerical properties. Application to industrial forming processes is demonstrated by means of three‐dimensional hot rolling and of superplastic sheet forming.