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Automatic Recognition of Emotions in Text
No full textReport published in the Proceedings of the National Conference on "Education and Research in the Information Society", Plovdiv, June, 2018With the rapid development of information technology and the expansion of the
Internet, social network users and bloggers generate a huge amount of emotionally rich text.
The automatic classification of emotions in the text is an area of interest to both social sciences
and applications, such as the discovery of attitudes towards a given product. This paper
presents and explores the machine learning methods used to classify emotions in the text. A
comparative study of the effectiveness of the classification of the main methods of solving this
task has been made. It also presents results from a study of correlations between the main
types of emotions in the text.Association for the Development of the Information Society, Institute of Mathematics and Informatics Bulgarian Academy of Sciences, Plovdiv University "Paisii Hilendarski
Application of Group and Team Work in Computer Modeling for Digital Competences
No full textReport published in the Proceedings of the National Conference on "Education and Research in the Information Society", Plovdiv, June, 2018The following work is devoted to the description of an alternative and methodological
approach for the training of students in Computer modeling in elementary school through the
application of group and team work. The aim is to increase the activity of students in the learning
process and to build digital competencies and skills for independent learning from an early age.
A description is given for the concepts of group and team, competencies and competency,
digital competencies and learning skills. Here is a proposed example for implementation of
projects for self-learning through the selected innovative approach as part of the curriculum for
3-4 grade in the discipline "Computer Modeling". The projects are implemented with a block
programming language Scratch.Association for the Development of the Information Society, Institute of Mathematics and Informatics Bulgarian Academy of Sciences, Plovdiv University "Paisii Hilendarski
New Reductions of a Matrix Generalized Heisenberg Ferromagnet Equation
Get PDF[Valchev Tihomir; Вълчев Тихомир]; [Yanovski Alexandar; Яновски Александър]In this report, we shall present a new 1 + 1 dimensional nonlinear partial differential equation integrable through inverse scattering transform. The integrable system under consideration is a pseudo-Hermitian reduction of a matrix generalization of classical 1 + 1 dimensional Heisenberg ferromagnet equation. We derive recursion operators and describe the integrable hierarchy related to that matrix equation. 2010 Mathematics Subject Classification: 17B80, 35G50, 37K10, 37K15
Dynamic Fracture of a Nano-Crack in Finite Exponentially Inhomogeneous Piezoelectric Solid
Get PDF[Marinov Marin; Маринов Марин]; [Rangelov Tsviatko; Рангелов Цвятко]; [Dineva Petia; Динева Петя]Aim of the study is to propose, develop, verify and apply in intensive simulations an efficient non-hypersingular traction boundary integral equation method (BIEM) for solution of anti-plane dynamic problem of a finite exponentially inhomogeneous piezoelectric solid with a nano-crack. The modelling approach is in the frame of continuum mechanics, wave propagation theory, the Gurtin and Murdoch surface elasticity theory and linear fracture mechanics. The simulations reveal the dependence of the stress concentration field on the electromechanical coupling, on the type and characteristics of the dynamic load, on the position-dependent material parameters, on the surface elasticity, on the size effect and on the wave-nanocrack-material gradient interaction. 2010 Mathematics Subject Classification: 35Q74, 74S15, 74H35
Effects of Time Rescaling for the Gas Dynamics Equations
Get PDFWe show that a special change of time variable allows to obtain splitting by physical processes in the barotropic gas dynamics equations. Namely, on the first time step the gas dynamics can be reduced to nonlinear heat equation, whereas on the second step the same system can be reduced to the pressureless gas dynamics equations with a friction term. We discuss also how the Cauchy data can be used on every step. Further, we show that in several cases there exists analytical representation of solution. 2010 Mathematics Subject Classification: 76N99
Heterogeneous IoT Platform for Device Management and Environmental Sensor Data Gathering
Get PDFIn this paper, we propose a new IoT platform which supports the use of different wired and radio connections to manage devices and gather environmental sensor data. We discuss the pilot implementation of our new platform which deals with the smart control of air-conditioning devices in shopping malls. The building blocks of the platform – two types of electronic controllers of our own design – are described in detail. The Internet connectivity of the platform enables the use of an Internetbased control center for storing historical data, performing statistical analyses, making automated corrections in the device control and providing possibilities for remote control by human operators. The end goal of the platform development is to achieve cost savings and increase the level of comfort of customers and employees.
ACM Computing Classification System (1998): B.4.0, C.2.0
Object-oriented Analysis for Design of Protein Fingerprints
Get PDFA new approach, based on object-oriented programming, for search and classification of protein patterns in a protein database is developed. Aiming at an improvement of the analysis of protein sequences and structures, certain basic patterns – such as motifs and fingerprints – are used. An unknown protein sequence can be classified by searching for those fingerprints from the database, assessing matches by estimating the statistical significance. The current implementation of the model algorithm for searching is a powerful tool that uses the PRINTS database as an example, however it does not support the option of adding of new features due to the conservative design of the program and the lack of publicly available code. A new version of the PRINTS database has recently been developed and this will require adding new features in the future. A novel object-oriented model for the implementation of the algorithm is proposed. This model is used to build a web application prototype, written in Python—the most widely used programming language in bioinformatics at present. The result of this study is a maintainable software with open source code that can easily be extended with new functionalities
Developing Computational Thinking Through Games in Scratch
Get PDFReport published in the Proceedings of the National Conference on "Education and Research in the Information Society", Plovdiv, June, 2018Computational thinking (CT), as a paradigm for learning computer science among
young students, has seen a large increase in popularity during recent years. Mainly it is
described as a problem-solving process that includes logical, analytical, algorithmic thinking
and dispositions, such as the ability to confidently deal with complexity and open-ended
problems. The goal is to inspire and engage the learners in such a way that they get an idea of
concepts on a concrete operational level. Its development could be supported by different
activities, including variety of curriculum approaches, workshops, summer schools, seminars
etc. In the paper we analyse the projects developed by primary school pupils during the
constructionist workshops and the projects developed by students, prospective computer
science teachers. We were interested in how the students understand computational concepts,
as a dimension of CT, reflected in their projects. We quantitatively assessed projects with Dr.
Scratch tool, which checks the presence of the previously mentioned concepts and offers a
feedback report with ideas and tips how to improve the code, aiming to encourage students’
desire to keep on developing their programming skills. We compare the learning outcomes of
two different projects: Maze and Escape Room. Our focus is on differences in thinking between
pupils and students.Association for the Development of the Information Society, Institute of Mathematics and Informatics Bulgarian Academy of Sciences, Plovdiv University "Paisii Hilendarski
Teaching Informatics Through Game Programming - Pilot Study of Students Attitude
No full textReport published in the Proceedings of the National Conference on "Education and Research in the Information Society", Plovdiv, June, 2018In this paper some results regarding use of games programming as ground for
development of core programming knowledge and skills for students at 8th grade of secondary
school are discussed.Association for the Development of the Information Society, Institute of Mathematics and Informatics Bulgarian Academy of Sciences, Plovdiv University "Paisii Hilendarski
Mathematics in the World Around Me – an Event in the Framework of "STEM Discovery Week 2018"
No full textReport published in the Proceedings of the National Conference on "Education and Research in the Information Society", Plovdiv, June, 2018The article describes the process of preparing and bringing to life of "Mathematics in
the World around Me" – an event in the frames of the European initiative "STEM Discovery
Week 2018" for promoting the inquiry based STEM education. The problems faced and the
challenges overcome during the organization of such an event in a relatively short time by
means of ICT are being considered. The analysis of the results (the projects received, as well
as the participants' response to the final mathematical performance) shows that the children
could get hooked on mathematics if stimulated early enough to see its many-sided expressions
in real life.Association for the Development of the Information Society, Institute of Mathematics and Informatics Bulgarian Academy of Sciences, Plovdiv University "Paisii Hilendarski