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This paper develops criteria for an alternative concept of inequality dominance and shows how they relate to criteria for comparing relative poverty. The results warn inter alia against the use of some popular indices of inequality. They do, however, provide an ethical basis for the use of other popular indices of (restricted) inequality as potential relative poverty indices. The results also suggest an interesting extension of the Schutz coefficient as well as a use of Lorenz curves for the analysis of relative poverty and restricted inequality. A graphical illustration shows how the new criteria of restricted inequality dominance extend the ranking power of previously proposed inequality dominance criteria.

The purpose of this paper is to examine the distributions of earnings and education in Portugal in the early years of European integration, 1985 and 1991, a period when Portugal experienced strong nominal convergence following EU accession.

The paper explores the information provided by relative distribution analysis and covariate (education) decomposition to study the dynamics of the earnings distribution since these methodologies allow for the identification of polarization patterns that might have occurred over the period. More standard methodological instruments are also used as a reference: cardinal measures of inequality and the Lorenz stochastic dominance approach.

The median and average earnings of employees increased and there was also a rise in earnings inequality. Relative to 1985, in 1991 there were more employees with very low earnings but also more 1991 employees with high earnings and there were also more employees at the bottom and top ends of the earnings distribution. The analysis of the relative earnings distribution by level of education reveals substantial differences for the top end of the distributions with the proportion of 1991 employees receiving the highest earnings higher than for the original 1985 cohort. A regional disaggregation confirms that the overall employees’ earnings and education distributions characteristics are determined by the behaviour of coastal regions, while in the non-coastal regions a lower level of inequality is associated with lower levels of median and average earnings and a different polarization pattern.

The paper shows that inequality is not a recent phenomenon in the Portuguese economy and thus might be one of the sources of the growth slowdown Portugal is experiencing since the turn of the century and might continue to hamper growth in the future deserving deeper investigation.

The relationship between income inequality and polarization is an empirical fact: a change in equality might occur together with a change in polarization. At the same time, polarization might emerge while inequality remains constant. The outcome of this process entails relevant information on the evolution of the income distribution. We exploit the LIS database to perform a relative distribution analysis for six European countries. Our aim is describing how disposable income distributions evolved over time. The results indicate that polarization increased in all the considered countries, being the largest in the United Kingdom and the smallest in Italy. Nonetheless, in all the countries downgrading prevails over upgrading: the relevance of the middle class getting poorer is larger than the one of the middle class getting richer.

When health is measured by a bounded variable, differences in health can be presented as levels of attainment or shortfall. Measurement of heath inequality then usually involves the choice of either the attainment or the shortfall distribution, and this choice may affect comparisons of inequality across populations. A number of indices have been introduced to overcome this problem. This chapter proposes a framework in which attainment and shortfall distributions can be jointly analyzed. Joint distributions of attainments and shortfalls are defined from points of view consistent with concerns for relative, absolute or intermediate inequality. Inequality measures invariant according to the corresponding ethical criterion are then applied. A dominance criterion that guarantees unanimous rankings of the joint distributions is also proposed.

“It should also be noted that the objective of convergence and equal distribution, including across under-performing areas, can hinder efforts to generate growth. Contrariwise, the objective of competitiveness can exacerbate regional and social inequalities, by targeting efforts on zones of excellence where projects achieve greater returns (dynamic major cities, higher levels of general education, the most advanced projects, infrastructures with the heaviest traffic, and so on). If cohesion policy and the Lisbon Strategy come into conflict, it must be borne in mind that the former, for the moment, is founded on a rather more solid legal foundation than the latter” European Commission (2005, p. 9)Adaptation of Cohesion Policy to the Enlarged Europe and the Lisbon and Gothenburg Objectives.

Lattice Boltzmann method (LBM) is employed to explore friction factor of single-phase fluid flow through porous media and the effects of local porous structure including geometry of grains in porous media and specific surface of porous media on two-phase flow dynamic behavior, phase distribution and relative permeability. The paper aims to discuss this issue.

The 3D single-phase LBM model and the 2D multi-component multi-phase Shan-Chen LBM model (S-C model) are developed for fluid flow through porous media. For the solid site, the bounce back scheme is used with non-slip boundary condition.

The predicted friction factor for single-phase fluid flow agrees well with experimental data and the well-known correlation. Compared with porous media with square grains, the two-phase fluids in porous media with circle grains are more connected and continuous, and consequently the relative permeability is higher. As for the factor of specific porous media surface, the relative permeability of wetting fluids varies a little in two systems with different specific surface areas. In addition, the relative permeability of non-wetting fluid decreases with the increasing of specific surface of porous media due to the large flow resistance.

Fluid-fluid interaction and fluid-solid interaction in the SC LBM model are presented, and schemes to obtain immiscible two-phase flow and different contact angles are discussed. Two-off mechanisms acting on the wetting fluids is proposed to illustrate the relative permeability of wetting fluids varies a little in two systems with different specific surface.

This paper aims to study the transient flow characteristics in a mixed-flow pump during the start-up period.

In this study, numerical calculation of the internal flow field in a mixed-flow pump using the sliding mesh method was carried out. The regulation of the pressure, streamline and the relative speed during the start-up period was analyzed.

The trend of the simulated head is consistent with the experimental results, and the calculated head is around 0.3 m higher than the experimental head when the rotation speed reached the stable stage, indicating that the numerical method for the start-up process simulation of the mixed-flow pump has a high accuracy. At the beginning, the velocity inside the impeller changes little along the radius direction and the flow rate increases slowly during the start-up process. As the rotation speed reached the stable stage, the flow inside the impeller became steady, the vortex reduced and transient effects disappeared gradually.

The study results have significant value for revealing the internal unsteady flow characteristics of the mixed-flow pump and providing the reference for the design optimization of the mixed-flow pump.

The purpose of this paper is to present a shape optimization technique for powder forming processes based on the genetic algorithm approach. The genetic algorithm is employed to optimize the geometry of component based on a fixed‐length vector of design variables representing the changes in nodal coordinates. The technique is used to obtain the desired optimal compacted component by changing the boundaries of component and verifying the prescribed constraints.

The numerical modeling of powder compaction simulation is applied based on a large deformation formulation, powder plasticity behavior, and frictional contact algorithm. A Lagrangian finite element formulation is employed for large powder deformations. A cap plasticity model is used in numerical simulation of nonlinear powder behavior. The influence of powder‐tool friction is simulated by the use of penalty approach in which a plasticity theory of friction is incorporated to model sliding resistance at the powder‐tool interface.

Finally, numerical examples are analyzed to demonstrate the feasibility of the proposed optimization algorithm for designing powder components in the forming process of powder compaction.

A shape optimization technique is presented for powder forming processes based on the genetic algorithm approach.

Electrical capacitance tomography (ECT) is a technique for reconstructing information about the spatial distribution of the contents of closed pipes by measuring variations in the dielectric properties of the material inside the pipe. In this paper, we propose a method that solves the non‐linear reconstruction problem directly leading to less iterations and higher accuracy than linear back projection algorithms currently in use in most ECT systems.