Abstract

Abstract
The security of systems and networks is a multidisciplinary challenge of increasingly importance which has stimulated the development of multiple solutions for an effective response to the requirements that are needed. In pursuing this demand much of the focus of security proposals has focused on ensuring mechanisms that prevent organizations from being attacked from outside their perimeter. However, the evolution of the tasks carried out by the internal organizations collaborators, which demand an increasing degree of use of computational resources and privileged access to multiple sources of information, emerge an increasing concern in the monitoring of the behaviours of the users. In addition to this problem, there is often an ill-defined borderline confusion over what internal workers should be able to do with the resources they have in organizations. The mix between strictly professional use and personal use can be problematic in organization's security context. Define organizations security policies, understand user' behaviours, act effectively over security incidents and promote users' organizational security culture, by a pedagogical approach seems to us to be a necessary advance in security frameworks nowadays. This paper presents a reflection on the aspects of internal security of Local Area Networks and proposes a conceptual security framework, which aims to contribute to an effective control and understanding of LANs user' behaviour, to a real-time response to unwanted occurrences but, especially, to a pedagogical approach to help the development of users' security culture.

Abstract
In this work, the thermo-optic coefficient (TOC) of ethanol-water mixtures, through refractive index and temperature measurements are determined using an etched optical fiber tip based on a multimode interferometer. The proposed probe is fabricated by fusion-splicing a 5.2 mm long coreless fiber section to a single mode fiber. To reduce the sensor dimensions and improve its sensitivity towards external medium variations, the fiber tip is subjected to wet chemical etching using a solution of 40% hydrofluoric acid, presenting a final diameter of 24.4 mu m. The TOC of each solution is estimated and, in the case of deionized water and pure ethanol, its value is of -1.128 x 10(-4) degrees C-1 and -3.117 x 10(-4) degrees C-1, respectively.

Abstract
Catalytic computation, defined by Buhrman, Cleve, Koucký, Loff and Speelman (STOC 2014), is a space-bounded computation where in addition to our working memory we have an exponentially larger auxiliary memory which is full; the auxiliary memory may be used throughout the computation, but it must be restored to its initial content by the end of the computation. Motivated by the surprising power of this model, we set out to study the non-deterministic version of catalytic computation. We establish that non-deterministic catalytic log-space is contained in ZPP, which is the same bound known for its deterministic counterpart, and we prove that non-deterministic catalytic space is closed under complement (under a standard derandomization assumption). Furthermore, we establish hierarchy theorems for non-deterministic and deterministic catalytic computation. © Harry Buhrman, Michal Koucký, Bruno Loff, and Florian Speelman; licensed under Creative Commons License CC-BY.

Abstract
Epilepsy diagnosis is typically performed through 2Dvideo-EEG monitoring, relying on the viewer's subjective interpretation of the patient's movements of interest. Several attempts at quantifying seizure movements have been performed in the past using 2D marker-based approaches, which have several drawbacks for the clinical routine (e.g. occlusions, lack of precision, and discomfort for the patient). These drawbacks are overcome with a 3D markerless approach. Recently, we published the development of a single-bed 3Dvideo-EEG system using a single RGB-D camera (Kinect v1). In this contribution, we describe how we expanded the previous single-bed system to a multi-bed departmental one that has been managing 6.61 Terabytes per day since March 2016. Our unique dataset collected so far includes 2.13 Terabytes of multimedia data, corresponding to 278 3Dvideo-EEG seizures from 111 patients. To the best of the authors' knowledge, this system is unique and has the potential of being spread to multiple EMUs around the world for the benefit of a greater number of patients. © 2018 European Federation for Medical Informatics (EFMI) and IOS Press.

Abstract
A reflective fiber optic sensor based on multimode interference for the measurement of refractive index variations in glucose aqueous solutions is proposed. The sensor is fabricated by splicing a short section of coreless silica fiber to standard single mode fiber. The influence of the coreless fiber dimensions on the sensor performance is analyzed. By changing the sensor length, no significant impact is observed. However, the reduction of the sensing head diameter leads to a large improvement of the sensitivity. The smaller sensor, with a length of 5 mm and a diameter of 24 mu m, presents a maximum sensitivity of 1467.59 nm/RIU, for the refractive index range between 1.364 and 1.397 RIU. Taking into account the acquisition system, a maximum theoretical resolution of 6.8 x 10(-5) RIU is achieved.