Approximations of the aggregated interference statistics for outage analysis in massive MTC

This paper presents several analytic closed-form approximations of the aggregated interference statistics within the framework of uplink massive machine-type-communications (mMTC), taking into account the random activity of the sensors. Given its discrete nature and the large number of devices involved, a continuous approximation based on the Gram–Charlier series expansion of a truncated Gaussian kernel is proposed. We use this approximation to derive an analytic closed-form expression for the outage probability, corresponding to the event of the signal-to-interference-and-noise ratio being below a detection threshold. This metric is useful since it can be used for evaluating the performance of mMTC systems. We analyze, as an illustrative application of the previous approximation, a scenario with several multi-antenna collector nodes, each equipped with a set of predefined spatial beams. We consider two setups, namely single- and multiple-resource, in reference to the number of resources that are allocated to each beam. A graph-based approach that minimizes the average outage probability, and that is based on the statistics approximation, is used as allocation strategy. Finally, we describe an access protocol where the resource identifiers are broadcast (distributed) through the beams. Numerical simulations prove the accuracy of the approximations and the benefits of the allocation strategy.Peer ReviewedPostprint (published version

Corporate Income Taxation of Multinationals and Fiscal Equalization

This paper investigates the effect of fiscal equalization on the efficiency properties of corporate income tax rates chosen by symmetric countries in a Nash tax competition game under the taxation principles of Separate Accounting and Formula Apportionment. Fiscal equalization ensures efficiency if the marginal transfer just reflects the fiscal and pecuniary externalities of tax rates. In contrast to previous studies, tax base equalization (Representative Tax System) does not satisfy this condition, but combining tax revenue and private income equalization does, regardless of which taxation principle is implemented. Under Formula Apportionment, tax base equalization is superior to tax revenue equalization if the wage income externality is sufficiently large.separate accounting, formula apportionment, fiscal equalization

Corporate Income Taxation of Multinationals and Fiscal Equalization

This paper investigates the eect of scal equalization on the efficiency properties of corporate income tax rates chosen by symmetric countries in a Nash tax competition game under the taxation principles of Separate Accounting and Formula Apportionment. Fiscal equalization ensures efficiency if the marginal transfer just reects the scal and pecuniary externalities of tax rates. In contrast to previous studies, tax base equalization (Representative Tax System) does not satisfy this condition, but combining tax revenue and private income equalization does, regardless of which taxation principle is implemented. Under Formula Apportionment, tax base equalization is superior to tax revenue equalization if the wage income externality is suffciently large.Separate Accounting, Formula Apportionment, Fiscal Equalization

Corporate income taxation of multinationals and fiscal equalization

This paper investigates the effect of fiscal equalization on the efficiency properties of corporate income tax rates chosen by symmetric countries in a Nash tax competition game under the taxation principles of Separate Accounting and Formula Apportionment. Fiscal equalization ensures efficiency if the marginal transfer just reflects the fiscal and pecuniary externalities of tax rates. In contrast to previous studies, tax base equalization (Representative Tax System) does not satisfy this condition, but combining tax revenue and private income equalization does, regardless of which taxation principle is implemented. Under Formula Apportionment, tax base equalization is superior to tax revenue equalization if the wage income externality is sufficiently large

Liesegang patterns : Studies on the width law

The so-called "width law" for Liesegang patterns, which states that the positions x_n and widths w_n of bands verify the relation x_n \sim w_n^{\alpha} for some \alpha>0, is investigated both experimentally and theoretically. We provide experimental data exhibiting good evidence for values of \alpha close to 1. The value \alpha=1 is supported by theoretical arguments based on a generic model of reaction-diffusion.Comment: 7 pages, RevTeX, two columns, 5 figure

Tax Competition and Fiscal Equalization under Corporate Income Taxation

This paper challenges the view that tax base equalization by the so-called Representative Tax System (RTS) removes inefficient undertaxation in corporate tax competition. The innovation of the paper is that it focuses on a tax on corporate income, instead of the unit tax on capital considered in previous studies. We employ a tax competition model with fiscal equalization and show that the RTS fails to fully internalize pecuniary and fiscal externalities. As consequence, the RTS yields inefficiently low tax rates in the Nash equilibrium of the tax competition game between governments. Tax revenue equalization performs even worse, but combined with equalization of private income it implements the efficient tax rates on corporate income

Front motion in an A+B→CA+B\to C type reaction-diffusion process: Effects of an electric field

We study the effects of an external electric field on both the motion of the reaction zone and the spatial distribution of the reaction product, $C$, in an irreversible $A^- +B^+ \to C$ reaction-diffusion process. The electrolytes $A\equiv (A^+,A^-)$ and $B\equiv (B^+,B^-)$ are initially separated in space and the ion-dynamics is described by reaction-diffusion equations obeying local electroneutrality. Without an electric field, the reaction zone moves diffusively leaving behind a constant concentration of $C$-s. In the presence of an electric field which drives the reagents towards the reaction zone, we find that the reaction zone still moves diffusively but with a diffusion coefficient which slightly decreases with increasing field. The important electric field effect is that the concentration of $C$-s is no longer constant but increases linearly in the direction of the motion of the front. The case of an electric field of reversed polarity is also discussed and it is found that the motion of the front has a diffusive, as well as a drift component. The concentration of $C$-s decreases in the direction of the motion of the front, up to the complete extinction of the reaction. Possible applications of the above results to the understanding of the formation of Liesegang patterns in an electric field is briefly outlined.Comment: 13 pages, 13 figures, submitted to J. Chem. Phy

Derivation of the Matalon-Packter law for Liesegang patterns

Theoretical models of the Liesegang phenomena are studied and simple expressions for the spacing coefficients characterizing the patterns are derived. The emphasis is on displaying the explicit dependences on the concentrations of the inner- and the outer-electrolytes. Competing theories (ion-product supersaturation, nucleation and droplet growth, induced sol- coagulation) are treated with the aim of finding the distinguishing features of the theories. The predictions are compared with experiments and the results suggest that the induced sol-coagulation theory is the best candidate for describing the experimental observations embodied in the Matalon-Packter law.Comment: 9 pages, 7 figures, RevTe

Formation of Liesegang patterns: Simulations using a kinetic Ising model

A kinetic Ising model description of Liesegang phenomena is studied using Monte Carlo simulations. The model takes into account thermal fluctuations, contains noise in the chemical reactions, and its control parameters are experimentally accessible. We find that noisy, irregular precipitation takes place in dimension d=2 while, depending on the values of the control parameters, either irregular patterns or precipitation bands satisfying the regular spacing law emerge in d=3.Comment: 7 pages, 8 ps figures, RevTe