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The purpose of this paper is to describe the development of simulation tools dedicated to eddy current non destructive testing (ECNDT) on planar structures implying planar defects. Two integral approaches using the Green dyadic formalism are considered.

The surface integral model (SIM) is dedicated to ideal cracks, whereas the volume integral method is adapted to general volumetric defects.

The authors observed that SIM provides satisfactory results, except in some critical transmitting/receiving (T/R) configurations. This led us to propose a hybrid method based on the combination of the two previous ones.

This method enables to simulate ECNDT on planar structures implying defects with a small opening using T/R probes.

This paper aims to describe a recently proposed algorithm in terrain‐based cooperative UAV mapping of the unknown complex obstacle in a stationary environment where the complex obstacles are represented as curved in nature. It also aims to use an extended Kalman filter (EKF) to estimate the fused position of the UAVs and to apply the 2‐D splinegon technique to build the map of the complex shaped obstacles. The path of the UAVs are dictated by the Dubins path planning algorithm. The focus is to achieve a guaranteed performance of sensor based mapping of the uncertain environments using multiple UAVs.

An extended Kalman filter is used to estimate the position of the UAVs, and the 2‐D splinegon technique is used to build the map of the complex obstacle where the path of the UAVs are dictated by the Dubins path planning algorithm.

The guaranteed performance is quantified by explicit bounds of the position estimate of the multiple UAVs for mapping of the complex obstacles using 2‐D splinegon technique. This is a newly proposed algorithm, the most efficient and a robust way in terrain based mapping of the complex obstacles. The proposed method can provide mathematically provable and performance guarantees that are achievable in practice.

The paper describes the main contribution in mapping the complex shaped curvilinear objects using the 2‐D splinegon technique. This is a new approach where the fused EKF estimated positions are used with the limited number of sensors' measurements in building the map of the complex obstacles.

Purpose – We analyze equality of opportunity for earnings acquisition in France between 1973 and 1993 defining individual circumstances by parental earnings. We compare two different definitions of circumstances. In the first one they are measured by the father's earnings level, in the second one by the father's rank in the earnings distribution.

Methodology – First we use stochastic dominance tools. Then we decompose the evolution of inequality of opportunity using the mean logarithmic deviation and the results of regressions of descendants’ earnings on their parents’ earnings.

Findings – Inequality of opportunity has remained stable when conditioning on the earnings level of the father, whereas it has diminished when conditioning on his rank in the earnings distribution. The former result is explained by the stable intergenerational earnings elasticity. The latter by the decreasing wage inequality in the previous generation.

Originality – Our analysis emphasizes that the assessment of equality of opportunity and its evolution is very sensitive to the partition of circumstances used. Moreover, it stresses the complementarity between the discrete and the continuous approaches for measuring inequality of opportunity.

A series of six workshops was held to compare eddy current codes, using the six benchmark problems described in the following six papers. The problems include transient and steady‐state ac magnetic fields, close and far boundary conditions, magnetic and non‐magnetic materials. All the problems are based either on experiments or on geometries that can be solved analytically. The workshops and solutions to the problems are described. Results show that many different methods and formulations give satisfactory solutions, and that in many cases reduced dimensionality or coarse discretization can give acceptable results while reducing the computer time required.

Individuals are completely responsible for their outcomes (income, utility, health and so on) and, therefore, total inequality is due to individual responsible choices. This view has been challenged by philosophers and economists for the last three decades since the magnum opus by John Rawls (1971). These authors have argued that individuals are only responsible for their own efforts, and, therefore, people should be compensated for a variety of circumstances beyond their control. The meritocracy approach rejects the existence of circumstances and, in accordance with this, considers that total inequality is due to inequality of effort. On the contrary, the equality of opportunity approach recognizes the existence of factors that affect individuals and over which they have no control. For the former approach, the relevant equilizandum is individual freedom of access to education, positions and jobs. For the latter approach, the relevant equilizandum is the set of available opportunities to acquire those attributes required to compete for a position or job.

One major problem preventing further application and benefits from additive manufacturing (AM) nowadays is that AM build parts always end up with poor geometrical quality. To help improving geometrical quality for AM, this study aims to propose geometrical deviation identification and prediction method for AM, which could be used for identifying the factors, forms and values of geometrical deviation of AM parts.

This paper applied the skin model-based modal decomposition approach to describe the geometrical deviations of AM and decompose them into different defect modes. On that basis, the approach to propose and extend defect modes was developed. Identification and prediction of the geometrical deviations were then carried out with this method. Finally, a case study with cylinders manufactured by fused deposition modeling was introduced. Two coordinate measuring machine (CMM) machines with different measure methods were used to verify the effectiveness of the methods and modes proposed.

The case study results with two different CMM machines are very close, which shows that the method and modes proposed by this paper are very effective. Also, the results indicate that the main geometrical defects are caused by the shrinkage and machine inaccuracy-induced errors which have not been studied enough.

This work could be used for identifying and predicting the forms and values of AM geometrical deviation, which could help realize the improvement of AM part geometrical quality in design phase more purposefully.