TY  - JOUR
AU  - Čisar, Petar
AU  - Maravić Čisar, Sanja
AU  - Popović, Brankica
AU  - Kuk, Kristijan
AU  - Vuković, Igor
PY  - 2022
UR  - http://jakov.kpu.edu.rs/handle/123456789/1446
AB  - This paper deals with the application of artificial immune networks in continuous
function optimizations. The performance of the immunological algorithms is analyzed using
the Optimization Algorithm Toolkit. It is shown that the CLIGA algorithm has, by far, the
fastest convergence and the best score - in terms of the number of required iterations, for the
analyzed continuous function. Also, based on the test results, it was concluded, that the lowest
total number of iterations for the defined run time was achieved with the opt-IA algorithm,
followed by the CLONALG and CLIGA algorithms.
PB  - Budapest : Óbuda University
T2  - Acta Polytechnica Hungarica
T1  - Application of Artificial Immune Networks in Continuous Function Optimizations
VL  - 19
IS  - 7
SP  - 153
EP  - 164
DO  - 10.12700/APH.19.7.2022.7.8
ER  - 

@article{
author = "Čisar, Petar and Maravić Čisar, Sanja and Popović, Brankica and Kuk, Kristijan and Vuković, Igor",
year = "2022",
abstract = "This paper deals with the application of artificial immune networks in continuous
function optimizations. The performance of the immunological algorithms is analyzed using
the Optimization Algorithm Toolkit. It is shown that the CLIGA algorithm has, by far, the
fastest convergence and the best score - in terms of the number of required iterations, for the
analyzed continuous function. Also, based on the test results, it was concluded, that the lowest
total number of iterations for the defined run time was achieved with the opt-IA algorithm,
followed by the CLONALG and CLIGA algorithms.",
publisher = "Budapest : Óbuda University",
journal = "Acta Polytechnica Hungarica",
title = "Application of Artificial Immune Networks in Continuous Function Optimizations",
volume = "19",
number = "7",
pages = "153-164",
doi = "10.12700/APH.19.7.2022.7.8"
}

Čisar, P., Maravić Čisar, S., Popović, B., Kuk, K.,& Vuković, I.. (2022). Application of Artificial Immune Networks in Continuous Function Optimizations. in Acta Polytechnica Hungarica
Budapest : Óbuda University., 19(7), 153-164.
https://doi.org/10.12700/APH.19.7.2022.7.8

Čisar P, Maravić Čisar S, Popović B, Kuk K, Vuković I. Application of Artificial Immune Networks in Continuous Function Optimizations. in Acta Polytechnica Hungarica. 2022;19(7):153-164.
doi:10.12700/APH.19.7.2022.7.8 .

Čisar, Petar, Maravić Čisar, Sanja, Popović, Brankica, Kuk, Kristijan, Vuković, Igor, "Application of Artificial Immune Networks in Continuous Function Optimizations" in Acta Polytechnica Hungarica, 19, no. 7 (2022):153-164,
https://doi.org/10.12700/APH.19.7.2022.7.8 . .

TY  - JOUR
AU  - Čisar, Petar
AU  - Maravić Čisar, Sanja
PY  - 2020
UR  - http://jakov.kpu.edu.rs/handle/123456789/1529
AB  - The evolution of appropriate hardware and software platforms has resulted in intensive increase in suchapplications that have placed their action in the virtual world. This enables users a special experience – the experience of virtual reality (VR). The software for developing VR is in many ways specific and demanding. Having in mind its great diversity, this paper gives an overview of categorizations, general characteristics and evaluation methods. In addition, general principles of VR software development are especially elaborated, with an emphasis on creating and testing games.
PB  - Timisoara : Faculty Engineering Hunedoara, University Politehnica Timisoara
T2  - Acta Technica Corviniensis – Bulletin of Engineering
T1  - Development Concepts of Virtual Reality Software
VL  - 13
IS  - 3
SP  - 23
EP  - 29
UR  - https://hdl.handle.net/21.15107/rcub_jakov_1529
ER  - 

@article{
author = "Čisar, Petar and Maravić Čisar, Sanja",
year = "2020",
abstract = "The evolution of appropriate hardware and software platforms has resulted in intensive increase in suchapplications that have placed their action in the virtual world. This enables users a special experience – the experience of virtual reality (VR). The software for developing VR is in many ways specific and demanding. Having in mind its great diversity, this paper gives an overview of categorizations, general characteristics and evaluation methods. In addition, general principles of VR software development are especially elaborated, with an emphasis on creating and testing games.",
publisher = "Timisoara : Faculty Engineering Hunedoara, University Politehnica Timisoara",
journal = "Acta Technica Corviniensis – Bulletin of Engineering",
title = "Development Concepts of Virtual Reality Software",
volume = "13",
number = "3",
pages = "23-29",
url = "https://hdl.handle.net/21.15107/rcub_jakov_1529"
}

Čisar, P.,& Maravić Čisar, S.. (2020). Development Concepts of Virtual Reality Software. in Acta Technica Corviniensis – Bulletin of Engineering
Timisoara : Faculty Engineering Hunedoara, University Politehnica Timisoara., 13(3), 23-29.
https://hdl.handle.net/21.15107/rcub_jakov_1529

Čisar P, Maravić Čisar S. Development Concepts of Virtual Reality Software. in Acta Technica Corviniensis – Bulletin of Engineering. 2020;13(3):23-29.
https://hdl.handle.net/21.15107/rcub_jakov_1529 .

Čisar, Petar, Maravić Čisar, Sanja, "Development Concepts of Virtual Reality Software" in Acta Technica Corviniensis – Bulletin of Engineering, 13, no. 3 (2020):23-29,
https://hdl.handle.net/21.15107/rcub_jakov_1529 .

TY  - JOUR
AU  - Čisar, Petar
AU  - Odry, Peter
AU  - Maravić Čisar, Sanja
AU  - Stankov, Gordana
PY  - 2020
UR  - http://jakov.kpu.edu.rs/handle/123456789/1521
AB  - Spread spectrum is a technique used for transmitting telecommunications signals. This topic is relatively complex and can be challenging for students. Thus, programming language Octave has been introduced in the course curriculum of Telecommunication Systems as one of the powerful tools that aid in student understanding of the spread-spectrum principles. The purpose of this paper is to elaborate on the teaching method of spread-spectrum technique and its application in telecommunications, with the aim to make this topic understandable to students. The participants of the experiment were fifth-semester electrical engineering students (N = 86) at a college of applied sciences. To test the previous knowledge of students needed to understand the theory of spread spectrum, a pretest was carried out which refers to general terms from the fundamentals of telecommunications. With the aim to deeper apprehend the necessary theory from this area, the students had to solve examples from engineering practice using open source software Octave, as well as computational tasks, regarding both methods in spread-spectrum technology. It has been shown that thanks to the visualization of appropriate material, students of the experimental group understood in more detail the method of generating spread-spectrum signals and the influence of individual parameters on partial signals, in relation to students who did not have the opportunity to use Octave. The results of the research lead us to conclude that software like Octave should be included in courses like Telecommunication Systems as a supplement to the traditional teaching and learning methods.
PB  - Hoboken; NJ : John Wiley & Sons, Inc.
PB  - Chichester, West Sussex : John Wiley & Sons Ltd.
T2  - Computer Applications in Engineering Education
T1  - Teaching spread spectrum in the course Telecommunication Systems using Octave
VL  - 28
IS  - 2
SP  - 367
EP  - 383
DO  - 10.1002/cae.22199
ER  - 

@article{
author = "Čisar, Petar and Odry, Peter and Maravić Čisar, Sanja and Stankov, Gordana",
year = "2020",
abstract = "Spread spectrum is a technique used for transmitting telecommunications signals. This topic is relatively complex and can be challenging for students. Thus, programming language Octave has been introduced in the course curriculum of Telecommunication Systems as one of the powerful tools that aid in student understanding of the spread-spectrum principles. The purpose of this paper is to elaborate on the teaching method of spread-spectrum technique and its application in telecommunications, with the aim to make this topic understandable to students. The participants of the experiment were fifth-semester electrical engineering students (N = 86) at a college of applied sciences. To test the previous knowledge of students needed to understand the theory of spread spectrum, a pretest was carried out which refers to general terms from the fundamentals of telecommunications. With the aim to deeper apprehend the necessary theory from this area, the students had to solve examples from engineering practice using open source software Octave, as well as computational tasks, regarding both methods in spread-spectrum technology. It has been shown that thanks to the visualization of appropriate material, students of the experimental group understood in more detail the method of generating spread-spectrum signals and the influence of individual parameters on partial signals, in relation to students who did not have the opportunity to use Octave. The results of the research lead us to conclude that software like Octave should be included in courses like Telecommunication Systems as a supplement to the traditional teaching and learning methods.",
publisher = "Hoboken; NJ : John Wiley & Sons, Inc., Chichester, West Sussex : John Wiley & Sons Ltd.",
journal = "Computer Applications in Engineering Education",
title = "Teaching spread spectrum in the course Telecommunication Systems using Octave",
volume = "28",
number = "2",
pages = "367-383",
doi = "10.1002/cae.22199"
}

Čisar, P., Odry, P., Maravić Čisar, S.,& Stankov, G.. (2020). Teaching spread spectrum in the course Telecommunication Systems using Octave. in Computer Applications in Engineering Education
Hoboken; NJ : John Wiley & Sons, Inc.., 28(2), 367-383.
https://doi.org/10.1002/cae.22199

Čisar P, Odry P, Maravić Čisar S, Stankov G. Teaching spread spectrum in the course Telecommunication Systems using Octave. in Computer Applications in Engineering Education. 2020;28(2):367-383.
doi:10.1002/cae.22199 .

Čisar, Petar, Odry, Peter, Maravić Čisar, Sanja, Stankov, Gordana, "Teaching spread spectrum in the course Telecommunication Systems using Octave" in Computer Applications in Engineering Education, 28, no. 2 (2020):367-383,
https://doi.org/10.1002/cae.22199 . .

TY  - JOUR
AU  - Čisar, Petar
AU  - Maravić Čisar, Sanja
PY  - 2019
UR  - http://jakov.kpu.edu.rs/handle/123456789/1527
AB  - 5G (or fifth generation) represents the latest generation of mobile network technology, whose implementation is underway in some countries. This mobile system has undeniable advantages over its predecessors. This paper gives an overview of security aspects of 5G networks, based on data derived from available literature. Authentication and key management are fundamental processes to the security of cellular networks. That is why the emphasis in the paper is put on elaborating these security methods and comparing features with the previous 4G system. Authentication components in 5G are different in regard to 4G because of the new service–based architecture. Further, 3GPP and non–3GPP access networks are treated more equally. Also, in case of 5G, the user equipment uses the public key of the home network to encrypt permanent identifier before it is sent to a network. In 4G, this identifier is sent as clear text (unencrypted). Key structure is longer in 5G than in 4G because of the implementation of two additional keys. Despite the evident advantages, consideration must be given to the security challenges brought to 5G networks by new services, architectures and technologies. For example, authentication in 5G is not without deficiencies. Namely, user tracking ability in 5G may still be possible.
PB  - Timisoara : University Politehnica
T2  - ANNALS of the Faculty Engineering Hunedoara – International Journal of Engineering (Online)
T1  - Security Aspects of 5G Mobile Networks
VL  - 17
IS  - 4
SP  - 137
EP  - 143
UR  - https://hdl.handle.net/21.15107/rcub_jakov_1527
ER  - 

@article{
author = "Čisar, Petar and Maravić Čisar, Sanja",
year = "2019",
abstract = "5G (or fifth generation) represents the latest generation of mobile network technology, whose implementation is underway in some countries. This mobile system has undeniable advantages over its predecessors. This paper gives an overview of security aspects of 5G networks, based on data derived from available literature. Authentication and key management are fundamental processes to the security of cellular networks. That is why the emphasis in the paper is put on elaborating these security methods and comparing features with the previous 4G system. Authentication components in 5G are different in regard to 4G because of the new service–based architecture. Further, 3GPP and non–3GPP access networks are treated more equally. Also, in case of 5G, the user equipment uses the public key of the home network to encrypt permanent identifier before it is sent to a network. In 4G, this identifier is sent as clear text (unencrypted). Key structure is longer in 5G than in 4G because of the implementation of two additional keys. Despite the evident advantages, consideration must be given to the security challenges brought to 5G networks by new services, architectures and technologies. For example, authentication in 5G is not without deficiencies. Namely, user tracking ability in 5G may still be possible.",
publisher = "Timisoara : University Politehnica",
journal = "ANNALS of the Faculty Engineering Hunedoara – International Journal of Engineering (Online)",
title = "Security Aspects of 5G Mobile Networks",
volume = "17",
number = "4",
pages = "137-143",
url = "https://hdl.handle.net/21.15107/rcub_jakov_1527"
}

Čisar, P.,& Maravić Čisar, S.. (2019). Security Aspects of 5G Mobile Networks. in ANNALS of the Faculty Engineering Hunedoara – International Journal of Engineering (Online)
Timisoara : University Politehnica., 17(4), 137-143.
https://hdl.handle.net/21.15107/rcub_jakov_1527

Čisar P, Maravić Čisar S. Security Aspects of 5G Mobile Networks. in ANNALS of the Faculty Engineering Hunedoara – International Journal of Engineering (Online). 2019;17(4):137-143.
https://hdl.handle.net/21.15107/rcub_jakov_1527 .

Čisar, Petar, Maravić Čisar, Sanja, "Security Aspects of 5G Mobile Networks" in ANNALS of the Faculty Engineering Hunedoara – International Journal of Engineering (Online), 17, no. 4 (2019):137-143,
https://hdl.handle.net/21.15107/rcub_jakov_1527 .

TY  - JOUR
AU  - Čisar, Petar
AU  - Maravić Čisar, Sanja
PY  - 2019
UR  - http://jakov.kpu.edu.rs/handle/123456789/1525
AB  - Anomaly detection is used to monitor and capture traffic anomalies in network systems. Many anomalies manifest in changes in the intensity of network events. Because of the ability of EWMA control chart to monitor the rate of occurrences of events based on their intensity, this statistic is appropriate for implementation in control limits based algorithms. The performance of standard EWMA algorithm can be made more effective combining the logic of adaptive threshold algorithm and adequate application of fuzzy theory. This paper analyzes the theoretical possibility of applying EWMA statistics and fuzzy logic to detect network anomalies. Different aspects of fuzzy rules are discussed as well as different membership functions, trying to find the most adequate choice. It is shown that the introduction of fuzzy logic in standard EWMA algorithm for anomaly detection opens the possibility of previous warning from a network attack. Besides, fuzzy logic enables precise determination of degree of the risk.
PB  - Niš: Faculty of Electronic Engineering, University of Niš
T2  - Facta Universitatis. Series: Mechanical Engineering (Online)
T1  - EWMA Statistics and Fuzzy Logic in Function of Network Anomaly Detection
VL  - 32
IS  - 2
SP  - 249
EP  - 265
DO  - 10.2298/FUEE1902249C
ER  - 

@article{
author = "Čisar, Petar and Maravić Čisar, Sanja",
year = "2019",
abstract = "Anomaly detection is used to monitor and capture traffic anomalies in network systems. Many anomalies manifest in changes in the intensity of network events. Because of the ability of EWMA control chart to monitor the rate of occurrences of events based on their intensity, this statistic is appropriate for implementation in control limits based algorithms. The performance of standard EWMA algorithm can be made more effective combining the logic of adaptive threshold algorithm and adequate application of fuzzy theory. This paper analyzes the theoretical possibility of applying EWMA statistics and fuzzy logic to detect network anomalies. Different aspects of fuzzy rules are discussed as well as different membership functions, trying to find the most adequate choice. It is shown that the introduction of fuzzy logic in standard EWMA algorithm for anomaly detection opens the possibility of previous warning from a network attack. Besides, fuzzy logic enables precise determination of degree of the risk.",
publisher = "Niš: Faculty of Electronic Engineering, University of Niš",
journal = "Facta Universitatis. Series: Mechanical Engineering (Online)",
title = "EWMA Statistics and Fuzzy Logic in Function of Network Anomaly Detection",
volume = "32",
number = "2",
pages = "249-265",
doi = "10.2298/FUEE1902249C"
}

Čisar, P.,& Maravić Čisar, S.. (2019). EWMA Statistics and Fuzzy Logic in Function of Network Anomaly Detection. in Facta Universitatis. Series: Mechanical Engineering (Online)
Niš: Faculty of Electronic Engineering, University of Niš., 32(2), 249-265.
https://doi.org/10.2298/FUEE1902249C

Čisar P, Maravić Čisar S. EWMA Statistics and Fuzzy Logic in Function of Network Anomaly Detection. in Facta Universitatis. Series: Mechanical Engineering (Online). 2019;32(2):249-265.
doi:10.2298/FUEE1902249C .

Čisar, Petar, Maravić Čisar, Sanja, "EWMA Statistics and Fuzzy Logic in Function of Network Anomaly Detection" in Facta Universitatis. Series: Mechanical Engineering (Online), 32, no. 2 (2019):249-265,
https://doi.org/10.2298/FUEE1902249C . .