Prioritarianism in Health-Care: Resisting the Reduction to Utilitarianism

Tännsjö’s book Setting Health-Care Priorities defends the view that there are three main normative theories in the domain of distributive justice, and that these theories are both highly plausible in themselves, and practically convergent in their normative conclusions. All three theories (utilitarianism, the maximin/leximin theory and egalitarianism) point to a somewhat radical departure from the present distribution of medical resources: in particular, they suggest redirecting resources from marginal life extension to the care of mentally ill patients. In this paper I wish to argue, firstly, that prioritarianism should not be considered as an amendment to utilitarianism, as it is in Tännsjö’s view, but as a distinctive fourth option. This can best be appreciated if we focus on a reading of the theory that emphasizes its derivation from egalitarianism and its attempt to develop an intermediate approach between utilitarian and egalitarian intuitions. Secondly, in response to Tännsjö’s central objection to prioritarianism, I will argue that the theory does not apply in intrapersonal cases but is only relevant for decisions regarding the interpersonal distribution of benefits. Finally, I will suggest that a practical convergence of the four theories on specific issues such as artificial reproduction or mood enhancement is far less likely than Tännsjö seems to believe.

How biased are halo properties in cosmological simulations?

ABSTRACT Cosmological N-body simulations have been a major tool of theorists for decades, yet many of the numerical issues that these simulations face are still unexplored. This paper measures numerical biases in these large, dark matter-only simulations that affect the properties of their dark matter haloes. We compare many simulation suites in order to provide several tools for simulators and analysts which help mitigate these biases. We summarize our comparisons with practical ‘convergence limits’ that can be applied to a wide range of halo properties, including halo properties which are traditionally overlooked by the testing literature. We also find that the halo properties predicted by different simulations can diverge from one another at unexpectedly high resolutions. We demonstrate that many halo properties depend strongly on force softening scale and that this dependence leads to much of the measured divergence between simulations. We offer an empirical model to estimate the impact of such effects on the rotation curves of a halo population. This model can serve as a template for future empirical models of the biases in other halo properties.

Extremum Seeking Feedback With Wave Partial Differential Equation Compensation

This paper addresses the compensation of wave actuator dynamics in scalar extremum seeking (ES) for static maps. Infinite-dimensional systems described by partial differential equations (PDEs) of wave type have not been considered so far in the literature of ES. A distributed-parameter-based control law using back-stepping approach and Neumann actuation is initially proposed. Local exponential stability as well as practical convergence to an arbitrarily small neighborhood of the unknown extremum point is guaranteed by employing Lyapunov–Krasovskii functionals and averaging theory in infinite dimensions. Thereafter, the extension for wave equations with Dirichlet actuation, antistable wave PDEs as well as the design for the delay-wave PDE cascade are also discussed. Numerical simulations illustrate the theoretical results.

Determination of the frequencies and forms of free vibrations of pentagonal plates by the finite-element method

Frequencies and modes of free vibrations of an isotropic thin pentagonal plate of regular shape with various configurations of rigid attachment at the edges are determined using the finite element method (FEM). The results obtained for some pentagonal plates are compared with the results obtained for square plates of an equivalent mass with corresponding boundary conditions. We present the vibration modes of the studied plates and the topology of the vibration modes for some of the considered plates corresponding to the square plates with free edges and rigidly fixed edges. The reliability of the obtained results is ensured by the use of a substantiated mathematical model, the correct formulation of the problem and the practical convergence of the calculated frequencies when using the FEM.

VERIFICATION OF AN ENTROPY DISSIPATIVE QGD-SCHEME

An entropy dissipative spatial discretization has recently been constructed for the multidimensional gas dynamics equations based on their preliminary parabolic quasi-gasdynamic (QGD) regularization. In this paper, an explicit finite-difference scheme with such a discretization is verified on several versions of the 1D Riemann problem, both well-known in the literature and new. The scheme is compared with the previously constructed QGD-schemes and its merits are noticed. Practical convergence rates in the mesh L1-norm are computed. We also analyze the practical relevance in the nonlinear statement as the Mach number grows of recently derived necessary conditions for L2-dissipativity of the Cauchy problem for a linearized QGD-scheme.