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In the age of communication, piracy and copyright violations are emerging as a primary problem in our society. These issues produce an increasing loss of money and non-desirable situations in business. In order to provide some support, governments have approved multiple laws projects to toughen the legality. However, more efforts must be made in order to detect this illegal content and enforce the law. For this purpose, it is desirable to develop automatic tools which achieve this job. In this paper it is presented a framework based on a binary classifier which has been trained through supervised learning techniques. This classifier is able to label a website (as legal or not) focusing only on the URL domain. The work aim is experimental, hence we have used text processing techniques, several similarity metrics and different classification models, in order to evaluate the resulting outcomes. These latter have been promising, given a firm line of work in future.

An induction motor model construction and the validation of the model response to a filtering technique is analyzed in this paper. The filter is connected to the rotating machine terminals in order to suppress overvoltages due to the long cables and high frequency pulses of the inverter. With the help of high frequency measurements made by the authors on a 1.1kW induction motor, an accurate simulation with Matlab Simulink™ based on differential mode analysis, is made. The simulation shows realistic results for the determination of the filter parameters among different values of rise time and cable length.

An on line partial discharge test technique on rotating machines fed by inverters is analyzed in this paper. All the research to determine the configuration of the components was developed using simulation in Matlab Simulink™. The important fact is that the entire model was made with all the components and situations that result from partial discharges on the insulation of electrical rotating machines. The model of the rotating machine is in high frequency because is fed by an inverter in order to visualize the overvoltage and partial discharge phenomena. Voltage impulse and partial discharge pulse spectra is filtering by a multipole filter before be passed through a coupling capacitor, connected to the machine terminals. Interesting results are showing in this paper to verify the accuracy of this online partial discharge testing technique. Another objective is to find out the values of components parameters before to be implemented.

This paper presents a quantitative study of the use of the Wikipedia system by its users (both readers and editors), with special focus on the identification of time and kind-of-use patterns, characterization of traffic and workload, and comparative analysis of different language editions. The basis of the study is the filtering and analysis of a large sample of the requests directed to the Wikimedia systems for six weeks, each in a month from November 2007 to April 2008. In particular, we have considered the twenty most frequently visited language editions of the Wikipedia, identifying for each access to any of them the corresponding namespace (sets of resources with uniform semantics), resource name (article names, for example) and action (editions, submissions, history reviews, save operations, etc.). The results found include the identification of weekly and daily patterns, and several correlations between several actions on the articles. In summary, the study shows an overall picture of how the most visited language editions of the Wikipedia are being accessed by their users.

Open collaborative projects, like FLOSS development projects and open content creation projects (e.g. Wikipedia), heavily depend on contributions from their respective communities to improve. In this context, an important question for both researchers and practitioners is: what is the expected lifetime of contributors in a community? Answering this question, we will be able to characterize these communities as an appropriate model can show whether or not users maintain their interest to contribute, for how long we could expect them to collaborate and, as a result, improve the organization and management of the project. In this paper, we demonstrate that survival analysis, a wellknown statistical methodology in other research areas such as epidemiology, biology or demographic studies, is a useful methodology to undertake a quantitative comparison of the lifetime of contributors in open collaborative initiatives, like the development of FLOSS projects and the Wikipedia, providing insightful answers to this challenging question.

Developer turnover can result in a major problem when developing software. When senior developers abandon a software project, they leave a knowledge gap that has to be managed. In addition, new (junior) developers require some time in order to achieve the desired level of productivity. In this paper, we present a methodology to measure the effect of knowledge loss due to developer turnover in software projects. For a given software project, we measure the quantity of code that has been authored by developers that do not belong to the current development team, which we define as orphaned code. Besides, we study how orphaned code is managed by the project. Our methodology is based on the concept of software archaeology, a derivation of software evolution. As case studies we have selected four FLOSS (free, libre, open source software) projects, from purely driven by volunteers to company-supported. The application of our methodology to these case studies will give insight into the turnover that these projects suffer and how they have managed it and shows that this methodology is worth being augmented in future research.

Collaborative projects built around virtual communities on the Internet have gained momentum over the last decade. Nevertheless, their rapid growth rate rises some questions: which is the most effective approach to manage and organize their content creation process? Can these communities scale, controlling their projects as their size continues to grow over time? To answer these questions, we undertake a quantitative analysis of privileged users in FLOSS development projects and in Wikipedia. From our results, we conclude that the inequality level of user contributions in both types of initiatives is remarkably distinct, even though both communities present almost identical patterns regarding the number of distinct contributors per file (in FLOSS projects) or per article (in Wikipedia). As a result, totally open projects like Wikipedia can effectively deal with faster growing rates, while FLOSS projects may be affected by bottlenecks on committers who play critical roles.

Wikipedia is one of the most successful examples of massive collaborative content development. However, many of the mechanisms and procedures that it uses are still unknown in detail. For instance, how equal (or unequal) are the contributions to it has been discussed in the last years, with no conclusive results. In this paper, we study exactly that aspect by using Lorenz curves and Gini coefficients, very well known instruments to economists. We analyze the trends in the inequality of distributions for the ten biggest language editions of Wikipedia, and their evolution over time. As a result, we have found large differences in the number of contributions by different authors (something also observed in free, open source software development), and a trend to stable patterns of inequality in the long run.