Approaches to Compute Workflow Complexity

During the last 20 years, complexity has been an interesting topic that has been investigated in many fields of science, such as biology, neurology, software engineering, chemistry, psychology, and economy. A survey of the various approaches to understand complexity has lead sometimes to a measurable quantity with a rigorous but narrow definition and other times as merely an ad hoc label. In this paper we investigate the complexity concept to avoid a vague use of the term `complexity\u27 in workflow designs. We present several complexity metrics that have been used for a number of years in adjacent fields of science and explain how they can be adapted and use to evaluate the complexity of workflows

Gravitational perturbation of the BTZ black hole induced by test particles and weak cosmic censorship in AdS spacetime

We analyze the gravitational perturbations induced by particles falling into a three dimensional, asymptotically AdS black hole geometry. More specifically, we solve the linearized perturbation equations obtained from the geodesic motion of a ring-like distribution of test particles in the BTZ background. This setup ensures that the U(1) symmetry of the background is preserved. The non-asymptotic flatness of the background raises difficulties in attributing the significance of energy and angular momentum to the conserved quantities of the test particles. This issue is well known but, to the best of our knowledge, has never been addressed in the literature. We confirm that the naive expressions for energy and angular momentum are the correct definitions. Finally, we put an asymptotically AdS version of the weak cosmic censorship to a test: by attempting to overspin the BTZ black hole with test particles it is found that the black hole cannot be spun-up past its extremal limit.Comment: 6 pages, no figures; v2: minor corrections and reference added to match published versio

THE DETERMINANTS OF FOREIGN DIRECT INVESTMENT IN DEVELOPING COUNTRIES

The objective of this study is to shed light on the determinants of foreign direct investiment (FDI) in developing countries. In order to undertake it, we performe a econometric model based in panel data analysis for 38 developing countries (including transition economies) for the 1975-2000 period. Among the major conclusions we have that the FDI is correlated to level of schooling, economy's degree of openness, risk and variables related to macroeconomic performance like inflation, risk and average rate of economic growth. The results also show that the FDI has been closely associated with stock market performance. Lastly, a causality test between FDI and GDP is performed. There is evidence of the existence of causality in sense that GDP leading to FDI, but not vice versa.

Sexualidade na doença crónica e na deficiência física

A conjugação da doença e deficiência com a sexualidade resulta numa rede de conflitualidades que tendem a gerar turbulência no envolvimento sexua

Black holes die hard: can one spin-up a black hole past extremality?

A possible process to destroy a black hole consists on throwing point particles with sufficiently large angular momentum into the black hole. In the case of Kerr black holes, it was shown by Wald that particles with dangerously large angular momentum are simply not captured by the hole, and thus the event horizon is not destroyed. Here we reconsider this gedanken experiment for a variety of black hole geometries, from black holes in higher dimensions to black rings. We show that this particular way of destroying a black hole does not succeed and that Cosmic Censorship is preserved.Comment: 10 pages, 7 figures. RevTex4