Knowledge disclosure as intellectual property rights

We study a model in which an inventor discloses knowledge about its innovation and then a rival chooses the probability of attaining a competing invention. Disclosures, by creating prior art, diminish the probability that the rival has of receiving a patent for its invention (legal externality), but, by revealing knowledge, they decrease the marginal cost of R&D (knowledge externality). We stress the following result. If the knowledge externality is large compared to the legal externality, decreasing the patentability standards leads to fewer disclosures and may hinder R&D. We also determine the impact of changes in market payoffs on the equilibrium level of disclosures and R&D

Accuracy Issues for Numerical Waveforms

We study the convergence properties of our implementation of the 'moving punctures' approach at very high resolutions for an equal-mass, non-spinning, black-hole binary. We find convergence of the Hamiltonian constraint on the horizons and the L2 norm of the Hamiltonian constraint in the bulk for sixth and eighth-order finite difference implementations. The momentum constraint is more sensitive, and its L2 norm shows clear convergence for a system with consistent sixth-order finite differencing, while the momentum and BSSN constraints on the horizons show convergence for both sixth and eighth-order systems. We analyze the gravitational waveform error from the late-inspiral, merger, and ringdown. We find that using several lower-order techniques for increasing the speed of numerical relativity simulations actually lead to apparently non-convergent errors. Even when using standard high-accuracy techniques, rather than seeing clean convergence, where the waveform phase is a monotonic function of grid resolution, we find that the phase tends to oscillate with resolution, possibly due to stochastic errors induced by grid refinement boundaries. Our results seem to indicate that one can obtain gravitational waveform phases to within 0.05 rad. (and possibly as small as 0.015 rad.), while the amplitude error can be reduced to 0.1%. We then compare with the waveforms obtained using the cZ4 formalism. We find that the cZ4 waveforms have larger truncation errors for a given resolution, but the Richardson extrapolation phase of the cZ4 and BSSN waveforms agree to within 0.01 rad., even during the ringdown.Comment: version accepted to PR

The criminal governance, geography, and network features of extortive offences in El Salvador

This thesis studies offender choices associated with extortive offences in El Salvador, Central America. Super gangs like MS-13 and Barrio 18 have turned extortion into one of the most important impediments for economic development in various countries of the isthmus. The control, influence, and prevalence of the illicit organizations found in Latin American contexts such as El Salvador, are rare. Criminal actors take advantage of the state’s poor governance to rule over large portions of the territory, sometimes establishing secret deals with official authorities to legitimize their power. Yet, little is known about the impact these circumstances have on offender decision-making. Borrowing from political science, the studies in this thesis turn to the criminal governance framework to capture the conditions faced by extortionists during three separate periods in El Salvador’s recent history and examine their impact over offender decisions. The findings suggest that closer partnerships between illicit organizations and state agents remove constraints and add incentives that provide offenders with more options, but that these effects are mediated by features associated with crime groups and the contexts in which they operate. Using these results, this thesis proposes a preliminary conceptual model of offender choices in extortion under criminal governance

Electrodeposition of copper from mixed sulphate–chloride acidic electrolytes at rotating disc electrode

The effect of chloride ion on the deposition of copper from low metal concentrations in aqueous, acid sulphate solutions was investigated. The electrolytes contained 0·05 mol dm?3 CuSO4 and 0·5 mol dm?3 Na2SO4 at pH 2 and 296 K. The chloride ion concentration was varied in a wide range from 0·03 to 2·0 mol dm?3. Linear sweep voltammetry was carried out under well defined flow conditions at a smooth platinum rotating disc electrode. The progressive transition from a single, two-electron reaction for the reduction of Cu(II)?Cu(0) to two, single-electron reactions for the reduction sequence: Cu(II)?Cu(I)?Cu(0) was clearly evident as the chloride ion concentration increased. The charge transfer and mass transport characteristics of these reactions were evaluated. The formal potential for the Cu II) reduction to Cu(I), the shift in the potential region for complete mass transport controlled reduction of Cu(I) to Cu(0) and the potential for hydrogen evolution at the deposited copper were also studied. A semi-logarithmic relationship between exchange current density and half-wave potential for Cu(II)?Cu(I) with chloride ion was achieved when the Cl?/Cu(II) ratio in the electrolytes exceeded 2, due to the presence of the Cu(I) dichlorocuprous anion, CuCl2?