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

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

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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automatica
K. Arabadzhiev. Cask Ale Brewery Control System

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

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

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

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

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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