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We present a finite element toolbox for the computation of Bogoliubov-de Gennes modes used to assess the linear stability of stationary solutions of the Gross-Pitaevskii (GP) equation. Applications concern one (single GP equation) or two-component (a system of coupled GP equations) Bose-Einstein condensates in one, two and three dimensions of space. An implementation using the free software ▪is distributed with this paper. For the computation of the GP stationary (complex or real) solutions we use a Newton algorithm coupled with a continuation method exploring the parameter space (the chemical potential or the interaction constant). Bogoliubov-de Gennes equations are then solved using dedicated libraries for the associated eigenvalue problem. Mesh adaptivity is proved to considerably reduce the computational time for cases implying complex vortex states. Programs are validated through comparisons with known theoretical results for simple cases and numerical results reported in the literature. Program Title: FFEM_BdG_toolbox.zip CPC Library link to program files: https://doi.org/10.17632/dgypyc34gb.1 Licensing provisions: Apache 2.0 Programming language: ▪(v 4.12) free software (www.freefem.org) Nature of problem: The software computes Bogoliubov-de Gennes (BdG) complex modes of Bose-Einstein condensates described by the Gross-Pitaevskii (GP) equation. BdG equations are obtained by linearizing the GP equation (or the system of coupled GP equations) around a stationary solution. Obtained BdG modes are used to assess on the stability of stationary states. Solution method: Stationary states of the GP equation are obtained by a Newton algorithm. Parameter space is explored using a continuation on the chemical potential. Once the stationary (complex or real) state is captured accurately, BdG modes are computed by solving the associated eigenvalue problem with the ARPACK library. Complex eigenvalues and eigenvectors are computed and stored. The wave function is discretized by P2 (piece-wise quadratic) Galerkin triangular (in 2D) or tetrahedral (in 3D) finite elements. Mesh adaptation is implemented to reduce the computational time. Examples are given for stationary states in one- and two-component Bose-Einstein condensates. [ABSTRACT FROM AUTHOR]

This stand-alone tutorial gives an introduction to the QTest 2.1 public domain software package for the specification and statistical analysis of certain order-constrained probabilistic choice models. Like its predecessors, QTest 2.1 allows a user to specify a variety of probabilistic models of binary responses and to carry out state-of-the-art frequentist order-constrained hypothesis tests within a Graphical User Interface (GUI). QTest 2.1 automatizes the mathematical characterization of so-called "random preference models", adds some parallel computing capabilities, and, most importantly, adds tools for Bayesian inference and model selection. In this tutorial, we provide an in-depth introduction to the Bayesian features: We review order-constrained Bayesian p -values, DIC and Bayes factors, building on the data, models, and prior QTest based frequentist data analyses of an earlier (frequentist) tutorial by Regenwetter et al. (2014). • This paper provides a tutorial for the NSF -funded open-access public-domain QTEST 2.1 software. • QTEST 2.1 provides frequentist and Bayesian order-constrained inference for models of binary responses. • Relative to QTEST 1.0 , it adds Bayesian p values, DIC , and Bayes factors for model fitting and model selection. • Version 2.1 automates the mathematical characterization of "random preference models." • QTEST 2.1 has a stand alone Graphical User Interface (GUI) and Matlab source code versions, with the latter offering more features. [ABSTRACT FROM AUTHOR]

Abstract: A variety of classification algorithms for software defect detection have been developed over the years. How to select an appropriate classifier for a given task is an important issue in Data mining and knowledge discovery (DMKD). Many studies have compared different types of classification algorithms and the performances of these algorithms may vary using different performance measures and under different circumstances. Since the algorithm selection task needs to examine several criteria, such as accuracy, computational time, and misclassification rate, it can be modeled as a multiple criteria decision making (MCDM) problem. The goal of this paper is to use a set of MCDM methods to rank classification algorithms, with empirical results based on the software defect detection datasets. Since the preferences of the decision maker (DM) play an important role in algorithm evaluation and selection, this paper involved the DM during the ranking procedure by assigning user weights to the performance measures. Four MCDM methods are examined using 38 classification algorithms and 13 evaluation criteria over 10 public-domain software defect datasets. The results indicate that the boosting of CART and the boosting of C4.5 decision tree are ranked as the most appropriate algorithms for software defect datasets. Though the MCDM methods provide some conflicting results for the selected software defect datasets, they agree on most top-ranked classification algorithms. [Copyright &y& Elsevier]

Free software is being considered in the library environment as an alternative to commercial software applications. This paper discusses different types of tools used in libraries and the free software most commonly used for them. Furthermore, some real cases of tools already implemented are shown as well as a bibliography of the applications discussed. The text of this paper is based on the workshop that with the same title was presented at the 15th Andalusian Library Conference in Cordova, Spain, on October 2009. [ABSTRACT FROM AUTHOR]

UnDiFi-2D , an open source (free software) Un structured-grid, Di scontinuity Fi tting code, is presented. The aim of UnDiFi-2D is to model gas-dynamic discontinuities in two-dimensional (2D) flows as if they were true discontinuities of null thickness that bound regions of the flow-field where a smooth solution to the governing PDEs exists. UnDiFi-2D therefore needs to be coupled with an unstructured CFD solver that is used to discretize the governing PDEs within the smooth regions of the flow-field. Two different, in-house developed, CFD solvers are also included in the current distribution. The main features of the UnDiFi-2D software can be summarized as follows: Programming language UnDiFi-2D is written in standard Fortran 77/95; its design is highly modular in order to enhance simplicity of use, maintenance and allow coupling with virtually any existing CFD solver; Usability, maintenance and enhancement In order to improve the usability, maintenance and enhancement of the code also the documentation has been carefully taken into account. The git distributed versioning system has been adopted to facilitate collaborative maintenance and code development; Copyrights UnDiFi-2D is a free software that anyone can use, copy, distribute, change and improve under the GNU Public License version 3. The present paper is a manifesto of the first public release of the UnDiFi-2D code. It describes the currently implemented features, which are the result of more than a decade of still ongoing CFD developments. This work is focused on the computational techniques adopted and a detailed description of the main characteristics is reported. UnDiFi-2D capabilities are demonstrated by means of examples test cases. The design of the code allows to easily include existing CFD codes and is aimed at ease code reuse and readability. Program title: UnDiFi-2D CPC Library link to program files: https://doi.org/10.17632/5hwssmc2mx.1 Licensing provisions: GNU General Public License, version 3 Programming language: Fortran; developed and tested with Intel Fortran Compiler v. 18.0.3 and GNU gfortran. External routines: The code depends on several libraries and third-party packages which are detailed in the corpus of the text. Nature of problem: Numerical computation of flows with discontinuities. Solution method: Shock-fitting technique. Additional comments including restrictions and unusual features: • At present, UnDiFi-2D is validated for inviscid steady and unsteady two-dimensional flows without changes in the number of discontinuity lines and interaction points. • UnDiFi-2D implements a shock-fitting algorithm and can be coupled with unstructured cell-vertex solvers, with an Arbitrary Lagrangian-Eulerian (ALE) formulation. • UnDiFi-2D project adopts git [1], a free and open source distributed version control system. A public repository dedicated to UnDiFi-2D project [2] has been created on github [3], a web-based hosting service for software development projects using git versioning system. Finally, a comprehensive documentation is provided in the form of user manual developed in Pandoc [4]. [1] Git, a free and open source distributed version control system, http://git-scm.com. [2] UnDiFi-2D documentation, https://github.com/UnDiFi/UnDiFi-2D. [3] Github, a web-based hosting service for software development projects using git versioning system, https://github.com. [4] M. Dominici, TUGboat 35(1) (2014) 44-50. [ABSTRACT FROM AUTHOR]

• High-precision computation capabilities implemented in open-source framework YADE. • Full python support for all arbitrary precision types implemented in the C++ backend. • Benchmark of GNU gcc, Intel icpc and clang compilers for all precision types. • Importance of high precision is shown by simulations of an elastic triple pendulum. • The influence of high precision on damping, time step and energy is presented. This paper deals with the implementation of arbitrary precision calculations into the open-source discrete element framework YADE published under the GPL-2+ free software license. This new capability paves the way for the simulation framework to be used in many new fields such as quantum mechanics. The implementation details and associated gains in the accuracy of the results are discussed. Besides the "standard" double (64 bits) type, support for the following high-precision types is added: long double (80 bits), float128 (128 bits), mpfr_float_backend (arbitrary precision) and cpp_bin_float (arbitrary precision). Benchmarks are performed to quantify the additional computational cost involved with the new supported precisions. Finally, a simple calculation of a chaotic triple pendulum is performed to demonstrate the new capabilities and the effect of different precisions on the simulation result. [ABSTRACT FROM AUTHOR]

Abstract: Computational physics as a mode of studying the mathematical and physical sciences has grown world-wide over the past two decades, but this trend is yet to fully develop in Africa. The essential ingredients are there for this to happen: increasing internet connectivity, cheaper computing resources and the widespread availability of open source and freeware. The missing ingredients centre on intellectual isolation and the low levels of quality international collaborations. Low level of funding for research from local governments remains a critical issue. This paper gives a motivation for the importance of developing computational physics at the university undergraduate level, graduate level and research levels and gives suggestions on how this may be achieved within the African context. It is argued that students develop a more intuitive feel for the mathematical and physical sciences, that they learn useful, transferable skills that make our graduates well-sought after in the industrial and commercial environments, and that such graduates are better prepared to tackle research problems at the masters and doctoral levels. At the research level, the case of the African School Series on Electronic Structure Methods and Applications (ASESMA) is presented as a new multi-national modality for engaging with African scientists. There are many novel aspects to this School series, which are discussed. [Copyright &y& Elsevier]

This paper is a report of the results of migration to free software and open source technologies in the teaching area of Faculty 10 at the University of Informatics Sciences (UCI). The main difficulties arise from the technological paradigm shift are started and errors in the transition process are critically evaluated. In addition, it provides a more detailed analysis of the experiences of using Nova, distribution of GNU/Linux developed by the UCI. It also describes the process of creating, programming, and maintaining the product Nova Docencia, as well as its strengths and weaknesses. Finally, it defines objectives and perspectives for the generalization of this project in the future [ABSTRACT FROM AUTHOR]

This paper offers an alternative solution to the insufficient level of redundancy of the ETECSA's Call Center platforms in the country. The aim is to take advantage of the VoIP and the Free Software to achieve this goal. The selection of the new version was the result of a cost-benefit analysis of different technologies. After selecting the Asterisk PBX, its functionality for the service requirements was evaluated. So far, the results obtained are favorable. The proposal not only seeks to solve the problems detected, but may also be considered for the implementation of new centers or as a support for operating architectures growth. This alternative can optimize, economically speaking, a service with significant challenges. [ABSTRACT FROM AUTHOR]

Research and development in hydroinfomatics can play an important role in environmental impact assessment by integrating physically-based models, data-driven models and other Information and Communication Tools (ICT). An illustration is given in this paper describing the developments around the Soil and Water Assessment Tool (SWAT) to support the implementation of the EU Water Framework Directive. SWAT operates on the river basin scale and includes processes for the assessment of complex diffuse pollution; it is open-source software, which allows for site-specific modifications to the source and easy linkage to other hydroinformatics tools. A crucial step in the world-wide applicability of SWAT was the integration of the model into a GIS environment, allowing for a quick model set-up using digital information on terrain elevation, land use and management, soil properties and weather conditions. Model analysis tools can be integrated with SWAT to assist in the tedious tasks of model calibration, parameter optimisation, sensitivity and uncertainty analysis and allows better understanding of the model before addressing scientific and societal questions. Finally, further linkage of SWAT to ecological assessment tools, Land Use prediction tools and tools for Optimal Experimental Design shows that SWAT can play an important role in multi-disciplinary eco-environmental impact assessment studies. [ABSTRACT FROM AUTHOR]

This paper offers an alternative solution to the insufficient level of redundancy of the ETECSA's Call Center platforms in the country. The aim is to take advantage of the VoIP and the Free Software to achieve this goal. The selection of the new version was the result of a cost-benefit analysis of different technologies. After selecting the Asterisk PBX, its functionality for the service requirements was evaluated. So far, the results obtained are favorable. The proposal not only seeks to solve the problems detected, but may also be considered for the implementation of new centers or as a support for operating architectures growth. This alternative can optimize, economically speaking, a service with significant challenges. [ABSTRACT FROM AUTHOR]

The article reviews the free online reference management tool Mendeley, located at www.mendeley.com, which can be used to organize electronic research papers and PDF files.