On the Mailbox Problem

The Mailbox Problem was described and solved by Aguilera, Gafni, and Lamport in their 2010 DC paper with an algorithm that uses two flag registers that carry 14 values each. An interesting problem that they ask is whether there is a mailbox algorithm with smaller flag values. We give a positive answer by describing a mailbox algorithm with 6 and 4 values in the two flag registers

Asymptotic iteration method for eigenvalue problems

An asymptotic interation method for solving second-order homogeneous linear differential equations of the form y'' = lambda(x) y' + s(x) y is introduced, where lambda(x) \neq 0 and s(x) are C-infinity functions. Applications to Schroedinger type problems, including some with highly singular potentials, are presented.Comment: 14 page

Frame synchronization performance and analysis

The analysis used to generate the theoretical models showing the performance of the frame synchronizer is described for various frame lengths and marker lengths at various signal to noise ratios and bit error tolerances

Novel types of anti-ecloud surfaces

In high power RF devices for space, secondary electron emission appears as the main parameter governing the multipactor effect and as well as the e-cloud in large accelerators. Critical experimental activities included development of coatings with low secondary electron emission yield (SEY) for steel (large accelerators) and aluminium (space applications). Coatings with surface roughness of high aspect ratio producing the so-call secondary emission suppression effect appear as the selected strategy. In this work a detailed study of the SEY of these technological coatings and also the experimental deposition methods (PVD and electrochemical) are presented. The coating-design approach selected for new low SEY coatings include rough metals (Ag, Au, Al), rough alloys (NEG), particulated and magnetized surfaces, and also graphene like coatings. It was found that surface roughness also mitigate the SEY deterioration due to aging processes.Comment: 4 pages, contribution to the Joint INFN-CERN-EuCARD-AccNet Workshop on Electron-Cloud Effects: ECLOUD'12; 5-9 Jun 2012, La Biodola, Isola d'Elba, Italy; CERN Yellow Report CERN-2013-002, pp.153-15

A basis for variational calculations in d dimensions

In this paper we derive expressions for matrix elements (\phi_i,H\phi_j) for the Hamiltonian H=-\Delta+\sum_q a(q)r^q in d > 1 dimensions. The basis functions in each angular momentum subspace are of the form phi_i(r)=r^{i+1+(t-d)/2}e^{-r^p/2}, i >= 0, p > 0, t > 0. The matrix elements are given in terms of the Gamma function for all d. The significance of the parameters t and p and scale s are discussed. Applications to a variety of potentials are presented, including potentials with singular repulsive terms of the form b/r^a, a,b > 0, perturbed Coulomb potentials -D/r + B r + Ar^2, and potentials with weak repulsive terms, such as -g r^2 + r^4, g > 0.Comment: 22 page

Economic assessment of investment in automatic feeding systems for sea bass grow-out farms of different sizes

The aim of this work was to run an economic assessment of investment in automatic feeding systems for grow-out farms of different sizes producing European sea bass in the Mediterranean Sea. For this, we have used an economic model to simulate the annual income statement of a typical farm with different production volumes: a small-sized farm with a production of 413 tons/year, a medium-sized farm of 1122 tons/year, and a large-sized farm of 2539 tons/year. With the values obtained in the simulation, we have carried out partial budget and investment analyses to estimate the economic value of this investment decision. To complement our economic assessment, a sensitivity analysis has also been run to include risk in the investment decision. Our findings show that the implementation of automatic feeding systems in sea bass grow-out farms would be a good economic decision, regardless of the farm size, since there are technological options suitable for different farm sizes and capital investment capacities. Consequently, innovation and investment in feeding management should not be impeded or limited by the farm size.info:eu-repo/semantics/publishedVersio

Discrimination Against Women in Formal Credit Markets: Reality or Rhetoric?

Microenterprises receive several forms of aid; however, many are denied access to formal finance. It is often argued that women entrepreneurs are frequently discriminated against in formal credit markets, but these arguments are often based on rhetoric and advocacy rather than rigorous analysis. In this study, the results of a multinomial logit model show that although a smaller total number of women than men entrepreneurs applied for loans, women entrepreneurs represent a higher proportion of applicants. Interestingly, the small probabilities of both male and female entrepreneurs being quantity rationed implies that this form of credit rationing is not widely exercised in special microenterprise programs in Ecuador

Credit Rationing in Small Scale Enterprises: Special Microenterprise Programs in Ecuador

Small scale enterprises receive several forms of aid, but many are denied access to formal loans. A demand and supply model is estimated to analyze the factors lenders use to ration credit in special microenterprise programs. The results reveal that suppliers do not discriminate against less profitable enterprises and entrepreneurs who have not completed their high school education; however, these entrepreneurs have a smaller demand for external finance from the microenterprise programs than more profitable enterprises and entrepreneurs who have graduated from high school