Month: October 2020

automatica
N. Deliiski, N. Tumbarkova, N. Trichkov, Z. Gochev, D. Angelski. Computing the Thermal Conductivity of Wood Details during One Sided Heating

saibg

Кey Words: Flat wood details; one sided heating; plasticizing; bending; temperature conductivity.

Abstract. An approach for the computation of the thermal conductivity of flat wood details during their one sided heating process before bending has been suggested. Mathematical descriptions of the specific heat capacity, thermal conductivity, and density of the non-frozen wood in the hygroscopic range have been introduced in own 1D non-linear mathematical model of one mentioned process. For the numerical solution of the model a software program has been prepared in the calculation environment of Visual FORTRAN Professional developed by Microsoft. With the help of the program, the 1D non-stationary temperature distribution along the thickness of subjected to one sided conductive heating flat wood details aimed at their plasticizing in the production of curved back parts of chairs has been calculated. The change in the thermal conductivity as a function of the temperature, moisture content, and basic density for beech details with an initial temperature of 20°C, moisture content of 0.15 kg.kg-1, and thickness of 16 mm during their 30 min one sided heating at temperature of 80°C, 100°C, and 120°C of the heating metal body has been computed, visualized and analyzed.

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Specificities of ERP Systems in Packaging Production from Corrugated Board

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Key Words: ERP systems; packaging production; corrugated board; recycled paper; model of implementation.

Abstract. The article presents typical features of planning and implementation of a specialized ERP system in packaging production plants from corrugated board. The specific requirements from the customer point of view for systems automation in the production of corrugated packaging from recycled paper are systematized. An overview and classification of the ERP systems has been made and various types of systems implementation are presented. A model of the process implementation of ERP systems in corrugated packaging factory and main phases of project realization is proposed. The phases of the project implementation and distribution of responsibilities of the participants are described. The key indicators that generate benefits of implementing ERP system in this type of production are referred.

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N. Angelov. Influence of Speed and Frequency of Repetition of Pulses on Laser Marking of Products from Steel 41Cr4

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Key Words: Laser marking; numerical experiments; fiber laser; steel 41Cr4; speed; frequency; power density.

Abstract. The advantages of laser marking over other marking methods are discussed. The influence of speed and frequency on the process of laser marking by melting with a fiber laser on specimens of structural steel 41Cr4 was investigated. Numerical experiments were received using the program TEMPERATURFELD3D. Graphics of the dependence of temperature from speed and frequency for two power densities were obtained. Preliminary work intervals of the speed and frequency for two power densities for the material under study were determined.

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education and qualification
I. Popchev. Artificial Intelligence in Secondary Education

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Key Words: Artificial intelligence; secondary schools; representation and knowledge processing; intelligent agents; semantic modeling; machine learning and emerging technologies.

Abstract. The article briefly introduces the published in 2019 by Izkustva Publishing House textbook “Artificial Intelligence. Solving Problems Through Search“ with authors Stanimir Stoyanov, Todorka-Glushkova and Yordan Todorov – lecturers at the Plovdiv University “Paisii Hilendarski”. The textbook adopts an algorithmic approach and the basic methods are presented as abstract algorithms, with curious examples, interesting questions and biographies of researchers added for a clearer understanding. According to the specific conditions in each school and class certain topics and tasks could be included or respectively excluded. The following textbooks are: knowledge representation and processing, intelligent agents, semantic modeling and machine learning. It has been suggested that other scientists, professors and specialists will be involved in writing textbooks on emerging technologies.

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education and qualification
S. Tsolova. Results from Approbation of Innovative Methodology for Education with Innovative ICT Tools

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Key Words: Approbation results; innovative methodology; David Kolb’s experiential learning cycle; Honey & Mumford learning types.

Abstract. The aim of this article is to present the results from a research, focused on the creation and evaluation of an innovative educational model, combining: Honey and Mumford learning styles, David Kolb experiential learning cycle and identification of the most effective innovative ICT technologies supporting the educational process for each learning style in the methodology of David Kolb’ experiential learning cycle. The presented in this article methodology was used as a basis for development of learning materials for university master degree course in the field of “Innovations and Innovation Management” and this gave opportunity for evaluation of the developed model: part of the course was implemented with traditional lectures without application of the presented here innovative model and later the same part of the course was implemented with application of the here presented innovative model and the specifically prepared for it learning materials. During the experiment the students filled in questionnaires in order to evaluate the used methods, learning materials and tasks in the course, the levels of acquired knowledge, level of involvement and satisfaction in the course. The results from this research presented in this article confirmed the successful application of the innovative methodology and the students’ preference towards educational process based on this methodology.

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education and qualification
K. Metodiev, D. Gocheva. Development of Standalone Applications for Teaching Materials

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Key Words: Standalone applications; industrial automation; teaching materials.

Abstract. Developing standalone applications to solve specific tasks is a convenient teaching tool. Standalone applications have been compiled from MATLAB code into executable files that can run outside of MATLAB for teaching materials in classes of Industrial Automation. Six standalone applications have been developed: four applications for the analysis of first- and second-order systems in time and frequency domains, one application to study time-delay systems and one to study systems with P, PI, PID controllers. The purpose of the present development is to share these applications with users who do not have MATLAB installed.

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education and qualification
S. Stavrev. FluurMat – A Stem Based Teaching Platform

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Key Words: Game development; software architecture; serious games; virtual floor.

Abstract. Play is the oldest form of learning. Nowadays, there are numerous examples of video games that are developed for educational purposes. The hardware medium those games are played also varies – from traditional desktop PC sand consoles, through mobile devices, to virtual reality head sets. The latest additions to that list are virtual walls and floors. In this paper, we present FluurMat [16] – a virtual floor for both educational and entertainment games. Furthermore, we demonstrate and discuss several examples of serious games that are implemented on the top of that architecture. We also briefly explain which specific abilities each one of those games trains.

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automatica
M. Hadjiski, N. Deliiski, N. Tumbarkova. Latent Heat of Fluids during their Phase Changes in Capillary Porous Materials

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Кey Words: Latent heat; fluids; crystallization; melting; vaporization; liquefaction; free water; bound water.

Abstract. Some basic characteristics and terms of the latent heat of solidification, fusion, vaporization, and liquefaction of the substances are being considered in this work. The processes of crystallization and vaporization of the substances have been described and analyzed. Theoretical foundations of the solidification and vaporization processes of the substances are in short given. Using data from the specialized literature, approaches for the calculation of the specific latent heat of fusion and vaporization of both the free and the bound water in capillary porous materials has been presented. The information about the specific latent heat of the water in mentioned materials is needed for scientifically based computing the non-stationary temperature distribution and energy consumption during their freezing, defrosting, drying, and model based control.

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D. Slavov. Mobile Robot Control Using Machine Vision Smart Camera

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Key Words: Mobile robot; automatic control; computer vision; machine vision; Arduino; Pixy; line tracking.

Abstract. This paper presents ways to control a mobile robot system for two different tasks: line tracking; and finding and passing through an opening in a vertical plane. The system is constructed of a threewheel platform, Arduino microcontroller and a smart camera Pixy2 for machine vision. For the line tracking task, based on the x and y coordinates at both ends of the visible line, measured by the camera, vector gradient is calculated and weight factors are adaptively determined for generating a two-component error fed to a PID controller. The feedback control successfully drives the robot over the line even in the presence of sharp turns. For the hole-passing task, the robot locates a color-illuminated opening in a vertical plane, moves frontally and passes through it. The system finds the frontal position by repeatedly measuring the opening width while maneuvering straight and diagonally towards it. Both tasks are successfully implemented despite the variable ambient lightning conditions.

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K. Arabadzhiev. Cask Ale Brewery Control System

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Key Words: Cask Ale Brewery; control; automation; Siemens control system.

Abstract. This article is about an automated Cask Ale Brewery Control System. Technical solution of controlling whole plant using Siemens S7-400, The standards and good automation practices of Briggs of Burton are applied. The document also defines how the control system will be structured to meet the User Requirements.

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informatics
B. Toskov, A. Toskova. Multi-agent Sensor Network

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Key Words: JADEX intelligent agents; BDI architecture; MQTT communication; Internet of Things; WiFi sensor network.

Abstract. This publication presents an experimental model of the architecture of an intelligent guard system developed on the concept of IoT. The Guard System is part of the cyber-physical space of the Faculty of Mathematics and Informatics at Plovdiv University. This model is built with JADEX intelligent agents and hardware sensors working on WiFi sensor network.

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informatics
V. Hadjiev, A. Rashidov. Overview and Analysis of Methods and Models for Data Structuring, Storage and Processing in the Internet

saibg

Key Words: Data-storage; Data-processing; Data-warehouse; Internet models; SWOT analysis; Cloud Database.

Abstract. This paper aims to review and analyze known models and methods for data structuring, storing and processing in the Internet. A SWOT analysis has been made to look at the strengths and weaknesses of known models.

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informatics
A. Panayotov, P. Ruskov. Implementing Cryptocurrency in Car Renting via Blockchain Protocol

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Key Words: Cryptocurrency; blockchain; smart contract; protocol; car renting.

Abstract. Car renting is spreading, while cars are increasingly smart and connected allowing autonomous behavior like self-driving, self-parking, etc. The process of renting, however, is usually cumbersome, involves transfer of sensitive data, is not entirely digital, is heavily regulated and involves different parties directly or indirectly. Therefore, the security, validity and traceability of the data involved is of vital importance. In this paper the authors discuss the blockchain opportunity to innovate the car renting business and present a model where the process is digitalized, simplified and data authenticity and security are guaranteed by using blockchain protocols, smart contracts and cryptocurrency.

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achievements and applications
D. Hristov, G. Georgiev, A. Stoyanova-Doycheva. Academic Pubication System

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Key Words: Virtual Physical Space; digital library; institutional repository; publication system.

Abstract. This article describes and analyzes the problems and tasks associated with the storage and processing of data in the Virtual Physical Space (ViPS), a scientific project of the University of Plovdiv Paisii Hilendarski. Existing storage platforms, in particular DSpace – an institutional repository application, and the possibilities of their application are being explored, not only as a publication tool, but also in a way that allows the integration of a digital library in ViPS and its interaction with the other components of the virtual space. A functional intelligent Web-based academic publication system is presented, created by implementing DSpace REST API, a programmatic interface to DSpace communities, collections, items, and bitstreams and by using the BDI (belief-desire-intention) software model for its agent part.

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automatica
S. Yordanov, K. Ormandzhiev, G. Mihalev. Some Possibilities for Robust Control of a Double-Operating Water Turbine

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Key Words: Robust control; cross-flow water turbine; H∞-norm; system uncertainty; load disturbance.

Abstract. A mathematical model describing the operation of the cross-flow water turbine has been developed in this paper. A robust governor has been synthesized using H∞ techniques to replace the conventional governor of the water turbine . The transient processes in the system are compared to the processes where the classical PID controller is used. The simulations are carried out using MATLAB and the results show that the overall system output performance can be improved using the proposed H∞ robust governor.

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informatics
V. Hadjiev, A. Rashidov. Overview and Analysis of Architectures for Data Structuring, Storage and Processing in the Cloud

saibg

Key Words: Data-storage; data-architectures; data-processing; data-warehouse; SWOT analysis; cloud architectures.

Abstract. This paper aims to review known architectures with application in data structuring, storage and processing. Concepts of architectures used in the construction of data warehouses have been discussed. A comparative analysis has been made, to look at the advantages and disadvantages of these architectures.

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intelligent systems
R. Trifonov, G. Pavlova, G. Tsochev. Problems of Collaborative Work of Humans and Robots

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Key Words: Collaborative work; humans and robots; standards; risk management.

Abstract. Robots are a huge part of all human activities. In the industry is proven that collaborative work of humans and robots is more effective, than the production technologies without humans. This, in turn, a new range of problems was created, both in terms of productivity and in safe collaboration, especially for people. The present work sets out to solve the most essential problems for ensuring conflict-free operation while guaranteeing high performance and quality of the functional tasks performed.

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intelligent systems
S. Stankov. Finding Dangerous Objects with the Help of Artificial Neural Networks

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Key Words: Deep Neural Networks; R-CNN; object detection; classification; Safety system.

Abstract. Current paper presents an application of Deep Neural Networks in the field of detecting dangerous objects and violence in different areas. Using machine vision, combined with Deep Neural Networks makes possible to improve the safety of citizens in different areas such as the mall, local store and others where guards cannot act fast enough in case of a danger situation.

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intelligent systems
A. Toskova. Model of Recommended System in Intelligent Game-Based Learning Platform

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Key Words: Content recommendation; gamе-based learning; special educational needs; personalized learning; machine learning.

Abstract. This article presents an approach for creating a content recommendation model in a gamе-based learning platform designed for students with special educational needs. Various referral systems and existing opportunities for intelligent delivery of personalized learning content tailored to the individual needs of children are addressed.

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achievements and applications
D. Nikolov, M. Lazarova. Metaheuristics for Optimization in Resource Planning and Business Process Management

saibg

Key Words: Enterprise resource planning; business process management; optimization; job shop scheduling; metaheuristics; machine learning.

Abstract. The paper presents a metaheuristics based framework for resource planning optimization and business project management. Possibilities for utilization of metaheuristic algorithms are presented in view of solving job shop scheduling problem for resource planning in ERP. A general framework for resource planning and business process management is suggested that utilizes several metaheuristics approaches. The proposed framework allows integration in ERP based on development of an optimization agent in multiagent framework.

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