Fibonacci Oscillators in the Landau Diamagnetism problem

We address the issue of the Landau diamagnetism problem via $q$-deformed algebra of Fibonacci oscillators through its generalized sequence of two real and independent deformation parameters $q_1$ and $q_2$. We obtain $q$-deformed thermodynamic quantities such as internal energy, number of particles, magnetization and magnetic susceptibility which recover their usual form in the degenerate limit $q_1^2 + q_2^2$=1.Comment: Latex, 11 pages, two figures, version to appear in Physica

Scrum solo application in a project with a strong integration component

In Portugal, 90% of software developing companies are micro companies. In 2002, in the Brazilian market, about 60% of the software developing companies would start their activities with just a single developer (Pagotto, Fabrti, Lerario, and Gonçalves, 2016). The Scrum Solo methodology was developed having in mind, that there is a big need for organizing and managing the software development of teams comprised by a single individual. The underlying complexity of big systems and the underlying integration complexity makes the usage of techniques and processes that guarantee the control of the project vital. The methodology described in this document is validated with two application cases in a context of development. The first one is an extensive project, with strong integration component, and the second one the development of an application for process dematerialization. The Scrum Solo methodology performed well in both cases despite their differences. Nevertheless, more cases should be analysed with the emphasis in using different contexts namely other organizations.FCT – Fundação para a Ciência e Tecnologia within the R&D Units Project Scope: UIDB/00319/202

An experimental investigation on the influence of deactivation of a groove on the performance of a twin groove journal bearing

Laboratory tests have been carried out in order to assess the influence of groove activation and deactivation on the performance of a twin axial groove steadily loaded hydrodynamic journal bearing. Temperature distribution at the oil–bush interface, oil outlet temperature, total oil flow rate, partial oil flow rate (at each groove), and motor consumption were measured for several journal speeds and loads under constant feeding pressure (pf) and constant feeding temperature (Tf), at five different loading angles ( ). In this study, the corresponding groove was deactivated whenever negative oil flow rate was observed in it and results were compared. It was found that the groove deactivation strategy has profound influence on the bearing performance when negative flow rate occurs at one groove, preventing such undesirable effects as lubricant starvation at the loaded region of the bearing. Groove deactivation in the event of negative flow rate may be easily implemented by incorporating a check valve to the feeding system of each groove. Such strategy seems to be highly recommended for the safe operation of bearings subjected to high loads and load angles deviated from 90º

Virtual customer service: building your chatbot

Nowadays, there is a significant evolution in the simulation of conversations with humans through chats. These chatbots provide an improvement in organizational efficiency and enhance the performance in supporting customers and partners. That is why they are increasingly a trend on the web. There are several solutions to conversational virtual agents and chatbots at this time. Many of these solutions have built-in artificial intelligence, natural language processing, and understanding systems. This research aims to build a roadmap for those who want to develop a virtual assistant using a framework or a pre-built solution. This work compares the several products related to chatbots providing information that helps one to find the best solution for each case.INCT-EN - Instituto Nacional de Ciência e Tecnologia para Excitotoxicidade e Neuroproteção(UID/CEC/00319/2019

Development of self-diagnosis tests system using a DSL for creating new test suites for integration in a cyber-physical system

Testing Cyber-physical systems (CPS) requires highly qualified engineers to design the tests since its computational part is programmed in low-level languages. The origin of this work arises from the need to find a solution that optimizes this problem and allows abstracting the current methods so that the tests can be created and executed more efficiently. We intend to do this by creating a self-diagnosis tests system that allows us to automate some of the current processes in the creation and execution of test suites. The work presented here addresses the problem by creating a new self-diagnosis tests system that will guarantee the reliability and integrity of the CPS. In detail, this paper begins by exposing a study on the current state of the art of test automation, Keyword-driven Testing (KDT) methodology and Domain-specific Languages (DSL). A new modular and extensible architecture is proposed for self-diagnosis tests systems based on two main concepts: the creation of a DSL combined with the use of the KDT methodology, as well as a methodology to extend it and integrate it into a CPS. A new self-diagnosis tests system has been proposed that applies the proposed architecture proving that it is possible to carry out the self-diagnosis in real-time of the CPS and allowing the integration of any type of test. To validate the implementation of the system, 28 test cases were carried out to cover all its functionalities. The results show that all test cases passed and, therefore, the system meets all the proposed objectives.(undefined

Thermal properties of a solid through q-deformed algebra

We address the study of the thermodynamics of a crystalline solid by applying q-deformed algebras. We based part of our study by considering both Einstein and Debye models. We have mainly explored the q-deformed thermal and electric conductivities as a function of the Debye specific heat. The results led to the interpretation of the q-deformation acting as a factor of disorder or impurity modifying the characteristics of a crystalline structure as, for example, in the case of semiconductors.Comment: 8 pages, twocolumn, 12 figures, Latex, version to appear in Physica

Kerr black holes with self-interacting scalar hair: Hairier but not heavier

The maximal Arnowitt-Deser-Misner (ADM) mass for (mini) boson stars (BSs)-gravitating solitons of Einstein's gravity minimally coupled to a free, complex, mass mu, Klein-Gordon field-is M-ADM(max) similar to M-Pl(2)/mu. Adding quartic self-interactions to the scalar field theory, described by the Lagrangian L-1 = lambda vertical bar Psi vertical bar(4), the maximal ADM mass becomes M-ADM(max) similar to root lambda M-Pl(3)/mu(2). Thus, for mini-BSs, astrophysically interesting masses require ultralight scalar fields, whereas self-interacting BSs can reach such values for bosonic particles with Standard Model range masses. We investigate how these same self-interactions affect Kerr black holes with scalar hair (KBHsSH) [C. A. R. Herdeiro and E. Radu, Kerr Black Holes with Scalar Hair, Phys. Rev. Lett. 112, 221101 (2014).], which can be regarded as (spinning) BSs in stationary equilibrium with a central horizon. Remarkably, whereas the ADM mass scales in the same way as for BSs, the horizon mass M-H does not increases with the coupling., and, for fixed mu, it is maximized at the "Hod point," corresponding to the extremal Kerr black hole obtained in the vanishing hair limit. This mass is always M-H(max) similar to M-Pl(2)/mu. Thus, introducing these self-interactions, the black hole spacetimes may become considerably "hairier" but the trapped regions cannot become "heavier." We present evidence that this observation also holds in a model with L-1 = beta vertical bar Psi vertical bar(6) - lambda vertical bar Psi vertical bar(4); if it extends to general scalar field models, KBHsSH with astrophysically interesting horizon masses require ultralight scalar fields. Their existence, therefore, would be a smoking gun for such (beyond the Standard Model) particles

Aspect-oriented fault tolerance for real-time embedded systems

Real-time embedded systems for safety-critical applications have to introduce fault tolerance mechanisms in order to cope with hardware and software errors. Fault tolerance is usually applied by means of redundancy and diversity. Redundant hardware implies the establishment of a distributed system executing a set of fault tolerance strategies by software, and may also employ some form of diversity, by using different variants or versions for the same processing. This paper describes our approach to introduce fault tolerance in distributed embedded systems applications, using aspect-oriented programming (AOP). A real-time operating system sup-porting middleware thread communication was integrated to a fault tolerant framework. The introduction of fault tolerance in the system is performed by AOP at the application thread level. The advantages of this approach include higher modularization, less efforts for legacy systems evolution and better configurability for testing and product line development. This work has been tested and evaluated successfully in several fault tolerant configurations and presented no significant performance or memory footprint costs.Fundação para a Ciência e a Tecnologia (FCT

Comparing reverse complementary genomic words based on their distance distributions and frequencies

In this work we study reverse complementary genomic word pairs in the human DNA, by comparing both the distance distribution and the frequency of a word to those of its reverse complement. Several measures of dissimilarity between distance distributions are considered, and it is found that the peak dissimilarity works best in this setting. We report the existence of reverse complementary word pairs with very dissimilar distance distributions, as well as word pairs with very similar distance distributions even when both distributions are irregular and contain strong peaks. The association between distribution dissimilarity and frequency discrepancy is explored also, and it is speculated that symmetric pairs combining low and high values of each measure may uncover features of interest. Taken together, our results suggest that some asymmetries in the human genome go far beyond Chargaff's rules. This study uses both the complete human genome and its repeat-masked version.Comment: Post-print of a paper accepted to publication in "Interdisciplinary Sciences: Computational Life Sciences" (ISSN: 1913-2751, ESSN: 1867-1462