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The growth of data volume has changed cybersecurity activities, demanding a higher level of automation. In this new cybersecurity landscape, text mining emerged as an alternative to improve the efficiency of the activities involving unstructured data. This article proposes a Systematic Literature Review ( SLR ) to present the application of text mining in the cybersecurity domain. Using a systematic protocol, we identified 2,196 studies, out of which 83 were summarized. As a contribution, we propose a taxonomy to demonstrate the different activities in the cybersecurity domain supported by text mining. We also detail the strategies evaluated in the application of text mining tasks and the use of neural networks to support activities involving unstructured data. The work also discusses text classification performance aiming its application in real-world solutions. The SLR also highlights open gaps for future research, such as the analysis of non-English content and the intensification in the usage of neural networks.

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Of paramount importance in the field of nanotechnology is the ability to measure reliably the properties of nanomaterials, especially their size. In general, just an estimate of size is not sufficient: a quantitative indication of the quality of the estimate in the form of an assessment of its uncertainty is necessary, as well. For example, standard ISO/IEC 17025:2017 (General Requirements for the Competence of Testing and Calibration Laboratories) stipulates that appropriate methods and procedures shall be used for laboratory activities and for the analysis of data, including the identification and quantification of all contributions to the measurement uncertainties.In order to facilite compliance with requirements such as these, we propose a procedure to establish an uncertainty budget for the measurement of the size of monodispersed nanoparticles in liquid suspension by dynamic light scattering (DLS). We take as a reference the general approach proposed in the Guide to the Expression of Uncertainty in Measurement (GUM). To our knowledge, this is the first time correlations that exist between the input quantities to the DLS measurement model are taken into account. An example involving a reference material consisting of 60 nm-nominal polystyrene nanoparticles suspended in water serves to illustrate our proposal.

ResumoNa indústria atual, a utilização de sistemas de controle é imprescindível. O presente trabalho visa expressar a necessidade de controlar a temperatura para a secagem de uma batelada de fumo e propor diferentes modelos para a realização. Para o controle de processo, faz-se necessária a caracterização da função de transferência, previamente estipulada. Através do software Matlab e do toolbox Simulink, arranjos de controle de quatro diferentes modelos de sintonia foram simulados, sendo eles: Ziegler-Nichols, Tyréus-Luyben, IMC Skogestad-Grimholt e Rivera-Morari. O processo foi caracterizado por uma função de sexta ordem, com comportamento oscilatório e resposta inversa. Para escolha do melhor modelo, que controla o processo, foram utilizados dois méto-dos. Primeiramente, comparações gráficas e, em segundo lugar, métodos de aproximação integral dos tipos ISE, IAE e ITAE. O modelo mais adequado para a realização de controle foi o de Ziegler-Nichols, com compensador de inversa, e um controlador do tipo Proporcional-Integral (PI).Palavras-chave: Controle de processo. Modelos de sintonia. Métodos Integrais. Abstract In current industry, the use of system control is indispensable. The present paper has the objective of expressing the need to control the temperature to dry a batch of tobacco and to