Abstract

Abstract
Mooshak is a web system with support for assessment in computer science. It was originally developed for programming contest management but evolved to be used also as a pedagogical tool, capitalizing on its programming assessment features. The current version of Mooshak supports other forms of assessment used in computer science, such as diagram assessment. This form of assessment is supported by a set of new features, including a diagram editor, a graph comparator, and an environment for integration of pedagogical activities. The first attempt to integrate these features to support diagram assessment revealed a number of shortcomings, such as the lack of support for multiple diagrammatic languages, ineffective feedback, and usability issues. These shortcomings were addressed by the creation of a diagrammatic language definition language, the introduction of a new component for feedback summarization and a redesign of the diagram editor. This paper describes the design and implementation of these features, as well as their validation. © Springer Nature Switzerland AG 2018.

Abstract
Animal experiments have gained importance in human diseases studies, namely neurological diseases and its biomechanical and physiological aspects. As a model of human disease, the rat offers many advantages over other organisms. For the biomechanical aspects of locomotion these studies are based on the analysis of animals' kinetic parameters, accessed through a locomotion measurement system. However, these systems are not yet thoroughly developed, are still scarce and are also very expensive when developed for studies using small rodents. In this paper, a system capable of measuring contact forces of small rodents is presented. The platform hardware is based on a 5 x 3 matrix of ultra-sensitive force sensors that produce a set of signals acquired in a LabVIEW (TM) environment, used for data acquisition and processing. The post processing steps include the removal of null data, curve normalization related to the rat's weight and expressed as percentage of passage, resulting in a gait pattern. The proposed cost-effective system has achieved excellent results regarding the locomotion profile of healthy animals.

Abstract
We propose a refractive index sensor based on surface plasmon resonance (SPR) in a gold wire partially incrusted on the surface of a D-type fiber and in contact with the external medium for increased sensitivity and roughness. The sensor is studied using numerical simulations based on the finite element method (FEM) and is compared with a more conventional D-type fiber SPR where the wire is replaced with a gold film. The numerical work estimates the sensitivity and resolution for different analytic refractive indexes (RI) in the range of 1.30-1.40, for a sensor based on the wavelength interrogation method. The results indicate that the use of the gold wire provides a better sensitivity when compared with the gold film, while supporting multiple peaks in different wavelengths, each with distinct values of sensitivity and resolution.

Abstract
The realization of tabletop optical analogue experiments of superfluidity relies on the engineering of suitable optical media, with tailored optical properties. This work shows how quantum atomic optical systems can be used to develop highly tunable optical media, with localized control of both linear and nonlinear susceptibility. Introducing the hydrodynamic description of light, the superfluidity of light in these atomic media is investigated through GPU-enhanced numerical simulations, with the numeric observation of the superfluidic signature of suppressed scattering through a defect.

Abstract
This paper addresses the problem of collision avoidance along specified paths in multiple mobile robot systems. These collisions can be represented by points of intersection or coincident segments between paths. The proposal of the work is to model these segments where the collision is possible through fictitious points. In addition, the advantages of the nonlinear versus mixed integer linear formulation, widely used in the literature, are verified. Comparisons were made and it’s proved the superiority of the proposed method with respect to complexity, computational time and inclusion of nonlinear constraints. Moreover, the simulations performed using this technique indicate that the method is promissory for applications in real systems. © Springer International Publishing AG 2018.