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MIPRO - path to knowledge and innovation

The IEEE reserves the right to exclude a paper from distribution after the conference (including its removal from IEEE Explore) if the paper is not presented at the conference.

Event program
Thursday, 5/24/2018 9:00 AM - 12:30 PM,
Leut B, Hotel Admiral, Opatija
9:00 AM - 9:15 AMOpening word  
9:15 AM - 12:15 PMPapers 
1.M. Alispahić, M. Vila, A. Akšamović (University of Sarajevo / Faculty of Electrical Engineering, Sarajevo, Bosnia and Herzegovina)
Simulator for Testing Algorithms for Estimation of Parameters of Power System 
In the paper, realized simulator for testing parameters estimation of the power system was described. Simulator allows definition of the test conditions like amplitude and phase, activity of decreasing direct component, variation of number of samples, variation of harmonic components, and change of frequency of the basic harmonic. The test criterion takes the error of the estimated value in relation to the default value and then time of convergence of the estimated value. As an illustration of algorithm functioning, the time format of the input signal and the timing response of the estimated amplitude and phase of signals are shown. In the simulator, algorithms for amplitude and phase estimation are implemented. For amplitude estimation, algorithms that were implemented: algorithm based on the Fourier bandwidth filter and algorithm based on the least squares method. For phase estimation, algorithms that were implemented: zero crossing algorithm and algorithm based on the Fourier bandwidth filter. All of the implemented algorithms are described and given with their mathematical models. Simulator was made in Matlab and can be expanded with addition of the noise, implementation of other algorithms, development and testing of new algorithms. For the demonstration of the usability of the simulator, results that were obtained by testing are shown.
2.A. Šantić, A. Akšamović (University of Sarajevo, Faculty of Electrical Engeenering, Sarajevo, Bosnia and Herzegovina)
Photovoltaic Plants in Bosnia and Herzegovina - State and Perspectives - 
This paper describes the current state of photovoltaic plants (PV) in Bosnia and Herzegovinia (BiH). It describes the ongoing trends in this field and the ongoing legislation, apart from the description, it gives a certain insight of the future development in this field of research concerning this geografical area. The first PV plant in BiH was built in 2012. Since then 180 PV plants were built and connected to the power grid containing installed power of 18 MW. This makes 0,37% of installed power in BiH. Because of these particular reasons BiH must, with the utmost seriousness, begin implementing projects of construction in the field of renewable energy and other forms of green energy. When considering renewable energy, solar energy it far most impresive and promissing area of investments. This paper has analized the potential that BiH has in the construction of PV plants. Four areas of interest were analized: the roof tops of apartment buildings, certain protective parts around the highways, water surfaces made by accumulation lakes and agriculturaly unefficient surfaces. The total estiment of the power provided from the PV plants are: 3,27 GW for the roof tops, 0,034 GW for the highways, 1,15 GW for the water surfaces and 4,52 GW for the agriculturaly unefficient surfaces.
3.F. Mujkić, A. Akšamović (Faculty of Electrical Engineering of Sarajevo/University of Sarajevo, Sarajevo, Bosnia and Herzegovina)
Implementation of an Electronic Platform for Aiding the Waste Management Process 
This paper describes the implemented system for detecting the state of the containers for collection of municipal waste. The data that is being collected contains following: fullness of the container, the position of the cover, and battery status. The data is transmitted via the Wi-Fi module ESP8266-12E to the broker, where an available management application system utilizes the transmitted data. The communication protocol that was used for that purpose is Message Queue Telemetry Transport (MQTT). The module operates autonomously, with a battery or solar powered source. Defect of efficient waste management has caused serious environmental problems and cost issues. A possible implementation of the system will be presented on the use case of the city of Sarajevo.
4.T. Špoljarić, C. Lušetić, V. Šimović (University of Applied Sciences, Zagreb, Croatia)
Optimization of PID Controller in AVR System by Using Ant Lion Optimizer Algorithm 
In this paper a novel optimization algorithm is proposed for efficient tuning of AVR controller in a closed loop generator control model. Ant lion optimizer is applied for fine tuning of PID controller parameters through model simulation and testing. A proposed algorithm uses single objective optimization method for acquiring an objective funtion's minimum. Several testing cases are used for simulation purposes and in all these cases a novel optimization method is compared with other swarm intelligence algorithms which have already been implemented as AVR controller optimization methods.
5.D. Razum, G. Šeketa, J. Vugrin, I. Lacković (Zagreb University, Faculty of Electrical Engineering and Computing, Zagreb, Croatia)
Optimal Threshold Selection for Threshold-based Fall Detection Algorithms with Multiple Features 
As people get older, their bodies go through multiple changes that make them more fragile and susceptible to falls. The population of elderly people living alone is increasing worldwide, and this imposes a risk that a potential fall may happen without receiving prompt attention of a healthcare provider or caregiver. To solve this problem, various solutions for automatic fall detection have been proposed that recognise when a person falls and send alarms to someone that could provide quick help. One group of automatic fall detectors use wearable sensors attached to a person’s body to measure body accelerations and then to distinguish falls from normal activities of daily living (ADLs) with some of the threshold or machine learning based algorithms. In threshold-based algorithms, features are calculated from the measured accelerations and they are evaluated with a set of rules to check whether a fall has happened. The choice of fixed thresholds is thereby important for the overall efficiency of the algorithm. In our previous works in the field of fall detection, we have analysed methods for the determination of appropriate threshold levels for algorithms based on one acceleration-based feature. In this paper, we present a method for setting optimal thresholds in algorithms that use multiple acceleration-derived features. We demonstrate the efficiency of algorithms with thresholds set according to the newly presented method when tested on our dataset of accelerations measured during simulated falls and ADLs.
6.A. Šeškar, B. Milašinović, K. Fertalj (Fakultet Elektrotehnike i Računarstva, Zagreb, Croatia)
Workflow for Image Categorization Using Cognitive Computing Services 
The paper describes structure of Azure Logic Apps and gives a brief overview of most relevant Computer Vision API services. Several solutions had been tested on a sample set consisting of cars or trucks photos in various street environments in order to show what kind of information could be extracted, e.g. licence plates, type of car, etc. in order to estimate feasibility of various development scenarios. As an example of integration of various cloud services, a workflow for image categorization using Microsoft Computer Vision API and an Azure Logic App had been developed and described in the paper. The Logic App workflow is triggered by taking photo on a mobile phone and uploading it to a cloud storage for which Logic Apps connector exists. The paper describes the developed workflow and discusses possibilities of replacing particular component with another one, i.e. replacing workflow trigger or cognitive computing service. An approximate maintenance price calculation is done by estimating number of executions of each Logic App function based on a sample set of photos. The paper concludes with solution drawbacks and future work possibilities.
7.I. Stančin, A. Jović (Sveučilište u Zagrebu Fakultet elektrotehnike i računarstva, Zagreb, Croatia)
Analyzing the Influence of Player Tracking Statistics on Winning Basketball Teams 
Basketball player tracking and hustle statistics became available since 2013-2014 season from National Basketball Association (NBA), USA. These statistics provided us with more detailed information about the played games. In this paper, we analyze statistically significant differences in these recent statistical categories between winning and losing teams. The main goal is to identify the most significant differences and thus obtain new insight about what it usually takes to be a winner. The analysis is done on three different scales: marking a winner in each game as a winning team, marking teams with 50 or more wins at the end of the season as a winning team, and marking teams with 50 or more wins in a season, but considering only their winning games, as a winning team. The results of the analysis reveal a few categories that have a significant impact on the winning teams, such as: the number of uncontested shots made, the number of assists and secondary assists, and the number of defensive rebound chances. Based on these results, we propose the effective passing ratio, a novel statistical category, which demonstrates large differences between winning and losing teams.
8.K. Host, D. Jakšić, P. Poščić (Department of informatics-University of Rijeka, Rijeka, Croatia)
Overview and Comparison of the Selected Data Modelling Tools 
The goal of this article is to introduce the basic characteristics of the databases modelling tools and to show how they are used through our own practical example. The main concepts regarding the article are defined in the introduction and the problem that will be described is presented. The criteria for the comparison of the given tools has been defined using previous research. The relational model of our “Fitness studio“ business case has been the basis for the comparison of three database modelling tools: ER/Studio, ModelRight and SQL Power Architect. The tools were described and compared with regards to the chosen criteria.
9.P. Poščić, I. Babić, D. Jakšić (Department of informatics-University of Rijeka, Rijeka, Croatia)
Temporal Functionalities in Modern Database Management Systems and Data Warehouses 
With the development of modern technologies and increasing number of data sources and inputs itself, there is a need to store old data for the purpose of analysis whose results are used in various areas. In order to use the old data storage for analysis, the analyst has to know when the data was valid which is possible using temporal tables or temporal databases. An overview and comparison of several software tools and solutions for working with databases and data warehouses, which use temporal functionalities, has been presented in this paper. The goal of this paper is to present an overview and analyze various software solutions and tools currently available on the market and make the conclusion which of those offer the best possibilities and what is expected in the future of this area.
12:15 PM - 12:30 PMClosing word and invitation for the presentations in the afternoon session 
Thursday, 5/24/2018 3:00 PM - 6:45 PM,
Leut B, Hotel Admiral, Opatija
3:00 PM - 3:15 PMOpening word  
3:15 PM - 6:30 PMPapers 
1.G. Miščević, E. Tijan, M. Jardas (University of Rijeka, Faculty of Maritime Studies, Rijeka, Croatia)
E-Learning in Logistics Education 
Following the implementation of Information and Communication Technologies in numerous segments of life, including the education system, the methods of teaching have significantly changed. Information and Communication Technologies have influenced the educational system which adapted to those trends and to the newer generations that spent their childhood playing with gadgets and learning at the same time. This is how the concept of e-learning and game-based learning emerged. In parallel, traditional logistics has evolved into e-logistics. When these two are combined, a logical sequence appears in which e-logistics at higher education levels is taught by e-learning techniques. This paper researches the means and tools for e-learning in logistics.
2.L. Bach, B. Mihaljević, M. Žagar (Rochester Institute of Technology Croatia, Zagreb, Croatia)
Comparative Analysis of Blockchain Consensus Algorithms 
Cryptocurrencies have seen a massive surge in popularity and behind these new virtual currencies is an innovative technology called the blockchain: a distributed digital ledger in which cryptocurrency transactions are recorded after having been verified. The transactions within a ledger are verified by multiple clients or “miners,” within the cryptocurrency’s peer-to-peer network using one of many varied consensus algorithms for resolving the problem of reliability in a network involving multiple unreliable nodes. The most widely used consensus algorithms are the Proof of Work (PoW) algorithm and the Proof of Stake (PoS) algorithm; however, there are also other consensus algorithms which utilize alternative implementations of PoW and PoS, as well as other hybrid implementations and some altogether new consensus strategies. In this paper, we perform a comparative analysis of typical consensus algorithms and some of their contemporaries that are currently in use in modern blockchains. Our analysis focuses on the algorithmic steps taken by each consensus algorithm, the scalability of the algorithm, the method the algorithm rewards miners for their time spent verifying blocks, and the security risks present within the algorithm. Finally, we present our conclusion and some possible future trends for consensus algorithms used in blockchains.
3.L. Amelio (University of Bologna, Bologna, Italy), A. Amelio (University of Calabria, Rende (CS), Italy)
CT Image Registration in Acute Stroke Monitoring 
We present a new system based on tracking the temporal evolution of stroke lesions using an image registration technique on CT exams of the patient's brain. Ths system is able to compare past CT exams with the most recent one related to stroke event in order to evaluate past lesions which are not related to stroke. Then, it can compare recent CT exams related to the current stroke for assessing the evolution of the ischemic lesion over time. A new similarity measure is also introduced for the comparison of the source and target images during image registration. It will result in a cheaper, faster and more accessible evaluation of the acute phase of the stroke overcoming the current limitations of the proposed systems in the state-of-the-art.
4.R. Šajina, T. Orehovački (Juraj Dobrila University of Pula, Pula, Croatia)
Development and Evaluation of an Application for Sharing Information About Courses 
Learning Management Systems (LMSs) such as Moodle are nowadays widely employed in higher education institutions. They enable teachers to publish educational materials and students to use them. Since students are not allowed to publish materials, they are turning to alternative ways of sharing information, most commonly through social networks. However, this approach of sharing information has a number of flaws such as poor content structure, lack of filtering options, and the fact that information shared by senior students are not available to their junior colleagues. This paper introduces the application whose purpose is addressing the aforementioned issues. Apart from functionalities that facilitate management and organization of content being shared, the application also has implemented gamification elements that encourage continuous use by students. With an aim to examine to what degree the application is accepted by students, an empirical study was carried out. Study findings are presented and discussed.
5.A. Drozina, T. Orehovački (Juraj Dobrila University of Pula, Pula, Croatia)
Creating a Tabletop Game Prototype in Unreal Engine 4 
This paper introduces QP_Tabletop (Quick Prototype Tabletop), an Unreal Engine 4 project created with the purpose of simplifying the process of creating a board game prototype. It allows users to quickly mock up an idea, and playtest it without spending time developing mechanics that may, or may not work well with the overall game. This allows user to quickly prototype using some predefined classes and behaviors most commonly found in typical board games, which in turn, allows them to focus on their idea early on, rather than thinking about implementation details. Basic classes of Unreal Engine 4 used in an implementation of QP_Tabletop, such as UObject, AActor and UComponent, as well as the classes of the application itself will be briefly explained. Special attention will be given to QPT_GameRule class, which is a class holding the game specific rules, the QPT_Actor class, representing the physical object of the game, such as a dice, card, board, etc., as well as QPT_CommonRule class, which contains common rules found in many board games, such as rolling multiple dice, shuffling cards, keeping player scores, changing current player in a turn based game, etc. The workflow and the interaction between these classes will be discussed as well.
6.H. Grgić, B. Mihaljević, A. Radovan (Rochester Institute of Technology Croatia, Zagreb, Croatia)
Comparison of Garbage Collectors in Java Programming Language 
Considering the need for continuous and uninterrupted service of modern software applications, it is valuable to analyze how garbage collection (GC) algorithms are handling memory challenges. Widely adopted general-purpose programming languages, like Java, represent an inevitable foundation for many modern application developments. In Java Platform, Standard Edition, and accompanying Java Virtual Machine (JVM), several GCs could be used. In the latest version 9.0.1 of Java SE Development Kit (JDK) default GC was changed to Garbage-First (G1) GC, now becoming widely adopted in addition to previously used Parallel GC and Concurrent Mark & Sweep (CMS) GC. Since GC is a vital part of JVM, changes and upgrades to its implementation, which reflect upon performance results, are properties worth exploring. Using benchmarks to create non-trivial memory pressures, and with extensive data monitoring, this paper analyzes insights gathered about critical performance factors across several GC algorithms. With the evaluation of benchmark elements, such as object allocations from young area to old area and the duration of the collection time, it was possible to compare GC behavior and assess the overall memory management. This paper presents our initial research performed in an academic environment on several benchmark cases, and our conclusion about it.
7.I. Čerjan (College for Information Technologies, Zagreb, Croatia), H. Tamburić (Faculty of Electrical Engineering and Computing, Zagreb, Croatia), D. Vještica Obradović (Erste&Steiermarkische Bank d.d, Zagreb, Croatia)
Metadata Management 
The name of the project is an acronym: MaDaMe stands for “metadata management“. It is an in-house project of Erste&Steirmarkische bank Zagreb. This paper describes the system which is used for managing domains and integrity restrictions (CHECK features) on database table fields. IBIS – an Integrated Banking Information System is an in-house banking system developed in Erste Bank Croatia. IBIS is used in Erste bank entities Croatia, Serbia and Montenegro. The development and maintenance of a system this size results in a great number of environments, some for development and others for testing. There are also three partially different production environments, different for a number of reasons: new laws and time needed for their implementation, user requests, the size of the market and market shares. For those reasons, it was necessary to create a standalone system that enables managing approved values in the system, depending on the country and/or the environment, was a necessity. The sheer size of the banking system and data sensitivity could produce extremely expensive errors, which is what makes MaDaMe a necessity.
8.A. Rekachinsky, R. Chulkevich, P. Kostenetskiy (South Ural State University, Chelyabinsk, Russian Federation)
Modeling Parallel Processing of Databases on the Central Processor Intel Xeon Phi KNL 
The development of parallel database management systems is an urgent problem due to the rapid information volume growth. Nowadays the basic principles of DBMS performance improvement include the use of multiprocessor systems [8]. At the same time, acceleration could be achieved by using new hardware architectures, such as hybrid clusters with multi-core coprocessors. The implementation of such architectures is limited by the high cost of harware and its configuration. Therefore, the development of models that allow determining several characteristics and comparing different database queries runtime without both using real hardware and taking into account the exact execution details is a highly topical problem. This paper describes the development of a mathematical model that explores the effectiveness of a new multi-core accelerator with Intel Xeon Phi Knights Landing hardware architecture in terms of parallel database processing.
9.M. Bošnjak, T. Orehovački (Juraj Dobrila University of Pula, Pula, Croatia)
Measuring Quality of an Indie Game Developed Using Unity Framework 
This paper provides an insight into the entire process of developing an Indie game by means of Unity framework. Special attention will be devoted to core game mechanics, such as colliders, physics components and ray casting. With an aim to determine to what extent introduced Indie game has met particular dimensions of quality, an empirical study was carried out. Data was gathered from the representative sample of gamers using post-use questionnaire. Outcomes of data analysis are presented and discussed.
10.R. Šajina, T. Orehovački (Juraj Dobrila University of Pula, Pula, Croatia)
User Experience Evaluation of 2D Side-Scrolling Game Developed Using Overlap2D Game Editor and LibGDX Game Engine 
Side scrolling games are currently one of the most popular mobile video games. It is a genre of games where a side-view camera angle is used for action viewing. This paper describes an implementation of a simple side scrolling game through integration of a Overlap2D presentation layer with a LibGDX logic layer using existing algorithms for collision detection and player movement. The implemented game retains most of the main features of modern side scrolling mobile video games such as various enemies with different shooting objects, diverse types of obstacles that a player must avoid, additional player features purchases and their consumption, multiple levels, and player movement through the level. Although games developed using LibGDX framework can be exported to multiple platforms, game presented in this paper is mainly focused on mobile platform. With an objective to examine to what extent developed game has met players’ expectations, an empirical study on user experience evaluation was carried out. Study findings are reported and discussed.
6:30 PM - 6:45 PMClosing word and invitation to attend presntations in other conference sessions  

Basic information:
Chairs:

Matej Janjić (Croatia), Dubravko Sabolić (Croatia), Nikola  Fijan (Croatia)

Registration / Fees:
REGISTRATION / FEES
Price in EUR
Up to 7 May 2018
After 7 May 2018
Members of MIPRO and IEEE
180
200
Students (undergraduate and graduate), primary and secondary school teachers
100
110
Others
200
220

The discount doesn't apply to PhD students.

Contact:

Matej Janjic
KSET
Unska 3
HR-10000 Zagreb, Croatia

GSM: +385 91 187 1140
E-mail: matej.janjic@fer.hr

The best papers will get a special award.
Accepted papers will be published in the ISBN registered conference proceedings. Papers written in English and presented at the Conference will be submitted for posting to IEEE Xplore.
There is a possibility that the selected scientific papers with some further modification and refinement are being published in the Journal of Computing and Information Technology (CIT).


International Program Committee General Chair:

Karolj Skala (Croatia)

International Program Committee:

Enis Afgan (Croatia), Slaviša Aleksić (Austria), Slavko Amon (Slovenia), Lene Andersen (Denmark), Vesna Anđelić (Croatia), Michael E. Auer (Austria), Dubravko Babić (Croatia), Snježana Babić (Croatia), Almir Badnjevic (Bosnia and Herzegovina), Marko Banek (Croatia), Mirta Baranović (Croatia), Bartosz Bebel (Poland), Ladjel Bellatreche (France), Petar Biljanović (Croatia), Eugen Brenner (Austria), Ljiljana Brkić (Croatia), Gianpiero Brunetti (Italy), Marian Bubak (Poland), Andrea Budin (Croatia), Željko Butković (Croatia), Željka Car (Croatia), Jesús Carretero Pérez (Spain), Matjaž Colnarič (Slovenia), Alfredo Cuzzocrea (Italy), Marina Čičin-Šain (Croatia), Marko Čupić (Croatia), Davor Davidović (Croatia), Marko Delimar (Croatia), Saša Dešić (Croatia), Todd Eavis (Canada), Maurizio Ferrari (Italy), Tiziana Ferrari (Netherlands), Bekim Fetaji (Macedonia), Nikola  Fijan (Croatia), Renato Filjar (Croatia), Tihana Galinac Grbac (Croatia), Enrico Gallinucci (Italy), Dragan Gamberger (Croatia), Paolo Garza (Italy), Liljana Gavrilovska (Macedonia), Ivan Gerlič (Slovenia), Matteo Golfarelli (Italy), Stjepan Golubić (Croatia), Montserrat Gonzales (United Kingdom), Francesco Gregoretti (Italy), Stjepan Groš (Croatia), Niko Guid (Slovenia), Jaak Henno (Estonia), Ladislav Hluchy (Slovakia), Željko Hocenski (Croatia), Vlasta Hudek (Croatia), Darko Huljenic (Croatia), Željko Hutinski (Croatia), Robert Inkret (Croatia), Mile Ivanda (Croatia), Hannu Jaakkola (Finland), Matej Janjić (Croatia), Leonardo Jelenković (Croatia), Rene Jerončić (Croatia), Dragan Jevtić (Croatia), Admela Jukan (Germany), Robert Jones (Switzerland), Peter Kacsuk (Hungary), Aneta Karaivanova (Bulgaria), Tonimir Kišasondi (Croatia), Marko Koričić (Croatia), Tomislav Kosanović (Croatia), Dieter Kranzlmüller (Austria), Marko Lacković (Croatia), Erich Leitgeb (Austria), Maria Lindén (), Dražen Lučić (Croatia), Marija Marinović (Croatia), Ludek Matyska (Czech Republic), Mladen Mauher (Croatia), Igor Mekjavic (Slovenia), Igor Mekterović (Croatia), Branko Mikac (Croatia), Veljko Milutinović (Serbia), Nikola Mišković (Croatia), Vladimir Mrvoš (Croatia), Jadranko F. Novak (Croatia), Predrag Pale (Croatia), Jesus Pardillo (Spain), Nikola Pavešić (Slovenia), Branimir Pejčinović (United States), Dana Petcu (Romania), Juraj Petrović (Croatia), Damir Pintar (Croatia), Željka Požgaj (Croatia), Slobodan Ribarić (Croatia), Janez Rozman (Slovenia), Rok Rupnik (Slovenia), Dubravko Sabolić (Croatia), Zoran Skočir (Croatia), Ivanka Sluganović (Croatia), Mario Spremić (Croatia), Vlado Sruk (Croatia), Stefano Stafisso (Italy), Uroš Stanič (Slovenia), Ninoslav Stojadinović (Serbia), Jadranka Šunde (Australia), Aleksandar Szabo (Croatia), Laszlo Szirmay-Kalos (Hungary), Davor Šarić (Croatia), Dina Šimunić (Croatia), Zoran Šimunić (Croatia), Dejan Škvorc (Croatia), Velimir Švedek (Croatia), Antonio Teixeira (Portugal), Edvard Tijan (Croatia), A. Min Tjoa (Austria), Roman Trobec (Slovenia), Sergio Uran (Croatia), Tibor Vámos (Hungary), Mladen Varga (Croatia), Marijana Vidas-Bubanja (Serbia), Mihaela Vranić (Croatia), Boris Vrdoljak (Croatia), Slavomir Vukmirović (Croatia), Yingwei Wang (Canada), Mario Weber (Croatia), Roman Wyrzykowski (Poland), Damjan Zazula (Slovenia)

Location:

Opatija, with its 170 years long tourist tradition, is the leading seaside resort of the Eastern Adriatic and one of the most famous tourist destinations on the Mediterranean. With its aristocratic architecture and style Opatija has been attracting renowned artists, politicians, kings, scientists, sportsmen as well as business people, bankers, managers for more than 170 years.

The tourist offering of Opatija includes a vast number of hotels, excellent restaurants, entertainment venues, art festivals, superb modern and classical music concerts, beaches and swimming pools and is able to provide the perfect response to all demands.

Opatija, the Queen of the Adriatic, is also one of the most prominent congress cities on the Mediterranean, particularly important for its international ICT conventions MIPRO that have been held in Opatija since 1979 gathering more than a thousand participants from more than forty countries. These conventions promote Opatija as the most desirable technological, business, educational and scientific center in Southeast Europe and the European Union in general.


For more details please look at www.opatija.hr/ and www.visitopatija.com

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