Healthy aging: a data-driven approach to Indicators of Compromise decaying models

Indicadores de Comprometimento (IoC) são a base do campo de inteligência de ameaças. Eles são utilizados em monitoradores de rede, gerando alertas quando uma correspondência é encontrada, permitindo que seja possível reagir a essas ameaças. No entanto, uma quantidade enorme de IoCs são gerados todo dia, tornando impossível monitorar cada IoC na mesma escala a longo prazo, além de aumentar a possibilidade de gerar alertas falsos. Neste trabalho, nos utilizamos de dados de rede reais de IoCs, e seus avistamentos, para modelar o decaimento da pontuação de IoCs ao longo do tempo. Começamos com a caracterização do nosso conjunto de dados e explicamos suas especificidades. Em seguida, apresentamos nossos modelos de tempo de vida (TTL), que podem receber como parâmetro uma porcentagem aceitável de perdas de avistamentos ou custos associados de monitoramento e de perda de um avistamento. Quando os valores absolutos dos custos associados ao monitoramento e perdas não estão disponíveis, mas a razão entre os mesmos pode ser estimada, propomos um terceiro modelo a ser adotado. Dada a razão entre custos, e o traço de avistamentos, o modelo fornece limiares além dos quais medidas extremas passam a ser ótimas. Em particular, quando a razão entre custos é menor que o limiar inferior, sempre monitorar todos os IoCs passa a ser ótimo. Similarmente, quando a razão entre custos é maior que o limiar superior calculado usando o modelo, a estratégia ótima consiste em nunca monitorar os IoCs

Comparison of input devices in an ISEE direct timbre manipulation task

The representation and manipulation of sound within multimedia systems is an important and currently under-researched area. The paper gives an overview of the authors' work on the direct manipulation of audio information, and describes a solution based upon the navigation of four-dimensional scaled timbre spaces. Three hardware input devices were experimentally evaluated for use in a timbre space navigation task: the Apple Standard Mouse, Gravis Advanced Mousestick II joystick (absolute and relative) and the Nintendo Power Glove. Results show that the usability of these devices significantly affected the efficacy of the system, and that conventional low-cost, low-dimensional devices provided better performance than the low-cost, multidimensional dataglove

How log-normal is your country? An analysis of the statistical distribution of the exported volumes of products

We have considered the statistical distributions of the volumes of the different products exported by 148 countries. We have found that the form of these distributions is not unique but heavily depends on the level of development of the nation, as expressed by macroeconomic indicators like GDP, GDP per capita, total export and a recently introduced measure for countries' economic complexity called fitness. We have identified three major classes: a) an incomplete log-normal shape, truncated on the left side, for the less developed countries, b) a complete log-normal, with a wider range of volumes, for nations characterized by intermediate economy, and c) a strongly asymmetric shape for countries with a high degree of development. The ranking curves of the exported volumes from each country seldom cross each other, showing a clear hierarchy of export volumes. Finally, the log-normality hypothesis has been checked for the distributions of all the 148 countries through different tests, Kolmogorov-Smirnov and Cramer-Von Mises, confirming that it cannot be rejected only for the countries of intermediate economy.Comment: 10 pages, 5 figures, submitted to IWcee15 conferenc

Bright X-ray flares in Orion young stars from COUP: evidence for star-disk magnetic fields?

We have analyzed a number of intense X-ray flares observed in the Chandra Orion Ultradeep Project (COUP), a 13 days observation of the Orion Nebula Cluster (ONC). Analysis of the flare decay allows to determine the size, peak density and magnetic field of the flaring structure. A total of 32 events (the most powerful 1% of COUP flares), have sufficient statistics for the analysis. A broad range of decay times (from 10 to 400 ks) are present in the sample. Peak flare temperatures are often very high, with half of the flares in the sample showing temperatures in excess of 100 MK. Significant sustained heating is present in the majority of the flares. The magnetic structures which are found, are in a number of cases very long, with semi-lengths up to 10^12 cm, implying the presence of magnetic fields of hundreds of G extending to comparable distance from the stellar photosphere. These very large sizes for the flaring structures ($ >> R_*) are not found in more evolved stars, where, almost invariably, the same type of analysis results in structures with L <= R_*. As the majority of young stars in the ONC are surrounded by disks, we speculate that the large magnetic structures which confine the flaring plasma are actually the same type of structures which channel the plasma in the magnetospheric accretion paradigm, connecting the star's photosphere with the accretion disk.Comment: Accepted to ApJS, COUP special issu