GOCE DELCEV UNIVERSITY - STIP, REPUBLIC OF NORTH MACEDONIA FACULTY OF COMPUTER SCIENCE ISSN 2545-4803 on line BALKAN JOURNAL OF APPLIED MATHEMATICS AND INFORMATICS (BJAMI) YEAR 2020 VOLUME III, Number 1 GOCE DELCEV UNIVERSITY - STIP, REPUBLIC OF NORTH MACEDONIA FACULTY OF COMPUTER SCIENCE ISSN 2545-4803 on line BALKAN JOURNAL OF APPLIED MATHEMATICS AND INFORMATICS (BJAMI) YEAR 2020 VOLUME III, Number 1 AIMS AND SCOPE: BJAMI publishes original research articles in the areas of applied mathematics and informatics. Topics: 1. Computer science; 2. Computer and software engineering; 3. Information technology; 4. Computer security; 5. Electrical engineering; 6. Telecommunication; 7. Mathematics and its applications; 8. Articles of interdisciplinary of computer and information sciences with education, economics, environmental, health, and engineering. Managing editor Biljana Zlatanovska Ph.D. Editor in chief Zoran Zdravev Ph.D. Lectoure Snezana Kirova Technical editor Slave Dimitrov Address of the editorial office Goce Delcev University – Stip Faculty of philology Krste Misirkov 10-A PO box 201, 2000 Štip, Republic of North Macedonia BALKAN JOURNAL OF APPLIED MATHEMATICS AND INFORMATICS (BJAMI), Vol 3 ISSN 2545-4803 on line Vol. 3, No. 1, Year 2020 EDITORIAL BOARD Adelina Plamenova Aleksieva-Petrova, Technical University – Sofia, Faculty of Computer Systems and Control, Sofia, Bulgaria Lyudmila Stoyanova, Technical University - Sofia , Faculty of computer systems and control, Department – Programming and computer technologies, Bulgaria Zlatko Georgiev Varbanov, Department of Mathematics and Informatics, Veliko Tarnovo University, Bulgaria Snezana Scepanovic, Faculty for Information Technology, University “Mediterranean”, Podgorica, Montenegro Daniela Veleva Minkovska, Faculty of Computer Systems and Technologies, Technical University, Sofia, Bulgaria Stefka Hristova Bouyuklieva, Department of Algebra and Geometry, Faculty of Mathematics and Informatics, Veliko Tarnovo University, Bulgaria Vesselin Velichkov, University of Luxembourg, Faculty of Sciences, Technology and Communication (FSTC), Luxembourg Isabel Maria Baltazar Simões de Carvalho, Instituto Superior Técnico, Technical University of Lisbon, Portugal Predrag S. Stanimirović, University of Niš, Faculty of Sciences and Mathematics, Department of Mathematics and Informatics, Niš, Serbia Shcherbacov Victor, Institute of Mathematics and Computer Science, Academy of Sciences of Moldova, Moldova Pedro Ricardo Morais Inácio, Department of Computer Science, Universidade da Beira Interior, Portugal Sanja Panovska, GFZ German Research Centre for Geosciences, Germany Georgi Tuparov, Technical University of Sofia Bulgaria Dijana Karuovic, Tehnical Faculty “Mihajlo Pupin”, Zrenjanin, Serbia Ivanka Georgieva, South-West University, Blagoevgrad, Bulgaria Georgi Stojanov, Computer Science, Mathematics, and Environmental Science Department The American University of Paris, France Iliya Guerguiev Bouyukliev, Institute of Mathematics and Informatics, Bulgarian Academy of Sciences, Bulgaria Riste Škrekovski, FAMNIT, University of Primorska, Koper, Slovenia Stela Zhelezova, Institute of Mathematics and Informatics, Bulgarian Academy of Sciences, Bulgaria Katerina Taskova, Computational Biology and Data Mining Group, Faculty of Biology, Johannes Gutenberg-Universität Mainz (JGU), Mainz, Germany. Dragana Glušac, Tehnical Faculty “Mihajlo Pupin”, Zrenjanin, Serbia Cveta Martinovska-Bande, Faculty of Computer Science, UGD, Republic of North Macedonia Blagoj Delipetrov, Faculty of Computer Science, UGD, Republic of North Macedonia Zoran Zdravev, Faculty of Computer Science, UGD, Republic of North Macedonia Aleksandra Mileva, Faculty of Computer Science, UGD, Republic of North Macedonia Igor Stojanovik, Faculty of Computer Science, UGD, Republic of North Macedonia Saso Koceski, Faculty of Computer Science, UGD, Republic of North Macedonia Natasa Koceska, Faculty of Computer Science, UGD, Republic of North Macedonia Aleksandar Krstev, Faculty of Computer Science, UGD, Republic of North Macedonia Biljana Zlatanovska, Faculty of Computer Science, UGD, Republic of North Macedonia Natasa Stojkovik, Faculty of Computer Science, UGD, Republic of North Macedonia Done Stojanov, Faculty of Computer Science, UGD, Republic of North Macedonia Limonka Koceva Lazarova, Faculty of Computer Science, UGD, Republic of North Macedonia Tatjana Atanasova Pacemska, Faculty of Electrical Engineering, UGD, Republic of North Macedonia C O N T E N T DISTANCE BASED TOPOLOGICAL INDICES ON MULTIWALL CARBON NANOTUBES SAMPLES OBTAINED BY ELECTROLYSIS IN MOLTEN SALTS .................. 7 Beti Andonovic, Vesna Andova, Tatjana Atanasova Pacemska, Perica Paunovic, Viktor Andonovic, Jasmina Djordjevic and Aleksandar T. Dimitrov CALCULATION FOR PHASE ANGLE AT RL CIRCUIT SUPPLIED WITH SQUARE VOLTAGE PULSE ................................................................................................. 13 Goce Stefanov, Vasilija Sarac, Maja Kukuseva Paneva APPLICATION OF THE FOUR-COLOR THEOREM FOR COLORING A CITY MAP ................................................................................................................ 25 Natasha Stojkovikj , Mirjana Kocaleva, Cveta Martinovska Bande , Aleksandra Stojanova and Biljana Zlatanovska DECISION MAKING FOR THE OPTIMUM PROFIT BY USING THE PRINCIPLE OF GAME THEORY .................................................................................................... 37 Shakoor Muhammad, Nekmat Ullah, Muhammad Tahir, Noor Zeb Khan EIGENVALUES AND EIGENVECTORS OF A BUILDING MODEL AS A ONE-DIMENSIONAL ELEMENT ......................................................................................... 43 Mirjana Kocaleva and Vlado Gicev exp(tA), (t R) 2 2 EXAMPLES OF GROUP exp(t A),(t ∈ R) OF 2×2× REAL MATRICES IN CASE MATRIX A DEPENDS ON SOMEA REAL PARAMETERS Ramiz Vugdalic .....................................................................................................................55 GROUPS OF OPERATORS IN C2 DETERMINED BY SOME COSINE OPERATOR FUNCTIONS IN C2 ................................................................................... 63 2 2 A Ramiz Vugdalić × exp(tA)(t R) 2 2 ∈ × COMPARISON OF CLUSTERING ALGORITHMS FOR THYROID DATABASE ................ 73 Anastasija Samardziska and Cveta Martinovska Bande MEASUREMENT AND VISUALIZATION OF ANALOG SIGNALS WITH A MICROCOMPUTER CONNECTION .......................................................................... 85 Goce Stefanov, Vasilija Sarac, Biljana Chitkusheva Dimitrovska GAUSSIANn METHOD FOR COMPUTING(n N) THE EARTH’S MAGNETIC FIELD .................. 95 Blagican n − DonevaA ∈ A × A ∞ Ak exp(A)=e := k! k=0 ∑A exp(0) = I, I exp((t + s)A) = exp(tA) exp(sA)(t, s R) A, B AB =∈BA exp(A + B) = exp(A) exp(B). Mn(C) n n · × ∞ tkAk t A exp(tA)= k! exp(tA) e ∥ ∥ (t R) k=0 ≤ ∈ ∑ n n A d × tA dt y(t)=Ay(t),y(0) = y0 y(t)=e y0 exp(tA)(t R) 2 2 2 ∈ × R 5 UDC: 519.174.7:528.9 APPLICATION OF THE FOUR-COLOR THEOREM FOR COLORING A CITY MAP NATASHA STOJKOVIKJ , MIRJANA KOCALEVA, CVETA MARTINOVSKA BANDE , ALEKSANDRA STOJANOVA AND BILJANA ZLATANOVSKA Abstract. A graph can be defined as a mathematical representation of a network, or as a set of points connected by lines. All kinds of transportation networks (air, rail), a telecommunication system, the internet … can be defined as graphs. Graph theory is a branch of mathematics and it had its beginnings in math problems. However, today it has grown into a significant area of mathematical research, with applications almost everywhere (in chemistry, operations research, social sciences, and computer science). In this paper a basic definition of graph theory some definitions of a chromatic number of a graph and certain theorems related to graph coloring are given. Then the problem of map coloring with four colors is considered. One way to consider this problem is with the theory of graphs, because graphs are closely related to maps. We considered the map of the metropolitan area of Shtip and Skopje. For coloring, we use the software “Four color theorem – map solver”. Keywords – graph, graph theory, maps, map coloring, algorithms. 1. Introduction Graphs are a very practical mathematical model and they are used in various areas of science and everyday life. With graphs, networks of places and paths that connect them, structural formulas of chemical compounds, people and relations between them and other problems can be represented. We are considering the problem of map coloring with four colors. Francis Garth set this problem in 1852. The problem consisted of the possibility of coloring the world map with only four colors, but two neighboring countries must not be colored with the same color. The problem intrigued many scientists and in 1976, Aphel and Hacken, with computer help, proved that coloring the world map required four colors [1]. This problem can be considered with the theory of graphs, more precisely as a problem of coloring a graph. Graphs are very closely related to maps, as every map can be treated as a graph. A graph consists of curves called links, and of their intersections called nodes. The problem of coloring the graph is reduced to coloring the nodes of the graph, so each node is accompanied by one color, and the adjacent nodes are not of the same color. Such a graph is said to be properly painted. When converting a map to a graph, the regions are converted to nodes and set of links to represent neighboring relations between regions [2]. In this paper, we regarded the map of the