This paper presents surrogate-model based optimization for synchronous reluctance motor (SynRm) with transversally laminated rotor. A radial basis function (RBF) model with 12 input variables and three outputs is first trained. A dataset is obtained using finite element method to estimate parameters of RBF model. By building RBF model, the RBF network can predicts the outputs of the SynRm with good accuracy Using non-dominated sorting genetic algorithm (NSGA II), pareto front is obtained. The SynRm is designed to maximize the maximum developed torque and power factor of the motor with constrained torque ripple.
{"title":"Optimization of synchronous reluctance motor based on radial basis network","authors":"Amir Erfani, J. Faiz","doi":"10.2298/sjee2002223n","DOIUrl":"https://doi.org/10.2298/sjee2002223n","url":null,"abstract":"This paper presents surrogate-model based optimization for synchronous reluctance motor (SynRm) with transversally laminated rotor. A radial basis function (RBF) model with 12 input variables and three outputs is first trained. A dataset is obtained using finite element method to estimate parameters of RBF model. By building RBF model, the RBF network can predicts the outputs of the SynRm with good accuracy Using non-dominated sorting genetic algorithm (NSGA II), pareto front is obtained. The SynRm is designed to maximize the maximum developed torque and power factor of the motor with constrained torque ripple.","PeriodicalId":37704,"journal":{"name":"Serbian Journal of Electrical Engineering","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68753412","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Intrusions into the computer systems are becoming increasingly sophisticated. Command and Control (C2) infrastructure, which enables attackers to remotely control infected devices, is a critical component. Malware is set to connect to C2 servers to receive commands and payloads, or upload logs or stolen files. Since techniques for detecting traditional C2 servers are also advancing, attackers look for ways to make C2 communication stealth and resilient. Increasingly, they hide C2 communications in plain sight, in particular on social media and other cloud-based public services. In this paper, we identify several emerging trends in the use of social media for C2 communications by providing a review of the existing research, discuss how attackers could combine these trends in the future to create a stealth and resilient server-less C2 model, look at possible defence aspects, and suggest further research.
{"title":"Malware command and control over social media: Towards the server-less infrastructure","authors":"Vladimir Radunovic, M. Veinovic","doi":"10.2298/sjee2003357r","DOIUrl":"https://doi.org/10.2298/sjee2003357r","url":null,"abstract":"Intrusions into the computer systems are becoming increasingly sophisticated. Command and Control (C2) infrastructure, which enables attackers to remotely control infected devices, is a critical component. Malware is set to connect to C2 servers to receive commands and payloads, or upload logs or stolen files. Since techniques for detecting traditional C2 servers are also advancing, attackers look for ways to make C2 communication stealth and resilient. Increasingly, they hide C2 communications in plain sight, in particular on social media and other cloud-based public services. In this paper, we identify several emerging trends in the use of social media for C2 communications by providing a review of the existing research, discuss how attackers could combine these trends in the future to create a stealth and resilient server-less C2 model, look at possible defence aspects, and suggest further research.","PeriodicalId":37704,"journal":{"name":"Serbian Journal of Electrical Engineering","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68754135","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zinelabiddine Mezache, Asma Slimani, F. Benabdelaziz
This paper is a new comparative study via numerical calculations and experimental measurements of various designs of fractal antennas. The geometry of the antennas dual‐broadband (2.5/5.77 GHz and 2.4/6.18 GHz) for WLAN/ WiMAX applications is inspired by the Sierpinski carpet and the Minkowski. The simulated and measured results show a good agreement over the bandwidth. We also performed a comparison with current comparable antenna designs, demonstrating the superiority of the proposed antenna regarding applicability in telecommunication technology.
{"title":"Design and analysis of a novel miniaturized microstrip fractal antenna for WLAN/WiMAX applications","authors":"Zinelabiddine Mezache, Asma Slimani, F. Benabdelaziz","doi":"10.2298/sjee2002213m","DOIUrl":"https://doi.org/10.2298/sjee2002213m","url":null,"abstract":"This paper is a new comparative study via numerical calculations and experimental measurements of various designs of fractal antennas. The geometry of the antennas dual‐broadband (2.5/5.77 GHz and 2.4/6.18 GHz) for WLAN/ WiMAX applications is inspired by the Sierpinski carpet and the Minkowski. The simulated and measured results show a good agreement over the bandwidth. We also performed a comparison with current comparable antenna designs, demonstrating the superiority of the proposed antenna regarding applicability in telecommunication technology.","PeriodicalId":37704,"journal":{"name":"Serbian Journal of Electrical Engineering","volume":"17 1","pages":"213-222"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68753333","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Todorovic, B. Jaksic, P. Spalevic, D. Bandjur, M. Bandjur
In this paper, the quality of the Polarization Shift Keying (PolSK) modulated signal in a Free Space Optical (FSO) system is analyzed. The atmospheric channel is statistically modeled with four different distributions, namely, the Gamma-Gamma distribution, Negative Exponential distribution, Kdistribution, and I-K distribution. For all four channel models, the Average Bit Error Rate (ABER) at the receiving side of the system is determined in an analytically closed form. The results are graphically presented and discussed in order to determine the impact of certain parameters on the ABER, i.e., the quality of the received signal in the PolSK modulated FSO system. These parameters are the Signal-to-Noise Ratio (SNR), the FSO link distance, the wavelength at which the signal is transmitted, and the atmospheric turbulence strength.
{"title":"Analysis of signal quality in FSO systems with PolSK modulation","authors":"J. Todorovic, B. Jaksic, P. Spalevic, D. Bandjur, M. Bandjur","doi":"10.2298/sjee2002171t","DOIUrl":"https://doi.org/10.2298/sjee2002171t","url":null,"abstract":"In this paper, the quality of the Polarization Shift Keying (PolSK) modulated signal in a Free Space Optical (FSO) system is analyzed. The atmospheric channel is statistically modeled with four different distributions, namely, the Gamma-Gamma distribution, Negative Exponential distribution, Kdistribution, and I-K distribution. For all four channel models, the Average Bit Error Rate (ABER) at the receiving side of the system is determined in an analytically closed form. The results are graphically presented and discussed in order to determine the impact of certain parameters on the ABER, i.e., the quality of the received signal in the PolSK modulated FSO system. These parameters are the Signal-to-Noise Ratio (SNR), the FSO link distance, the wavelength at which the signal is transmitted, and the atmospheric turbulence strength.","PeriodicalId":37704,"journal":{"name":"Serbian Journal of Electrical Engineering","volume":"17 1","pages":"171-186"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68753650","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The work presented in this paper concerns the study of the thermal behavior due to copper losses and iron losses of a switched reluctance machine with double salience (SRM6/4) by analytical coupling - 2D finite elements. Calculation by analytical methods of the conduction coefficients in the radial and axial direction as well as the convection coefficients in the air gap of this machine are presented. The values of these found coefficients are used to solve the transient thermal problem for this device using the ADEMEF2D software. The obtained results show a very large increase in temperature at the winding. Heat conduction in both radial and axial directions has a very large effect on the temperature value in all regions of the SRM6/4.
{"title":"Analysis of conductive and convective transfers in a double salience switched reluctance machine by analytical coupling-2D finite elements","authors":"Badache Souad","doi":"10.2298/sjee2003377s","DOIUrl":"https://doi.org/10.2298/sjee2003377s","url":null,"abstract":"The work presented in this paper concerns the study of the thermal behavior due to copper losses and iron losses of a switched reluctance machine with double salience (SRM6/4) by analytical coupling - 2D finite elements. Calculation by analytical methods of the conduction coefficients in the radial and axial direction as well as the convection coefficients in the air gap of this machine are presented. The values of these found coefficients are used to solve the transient thermal problem for this device using the ADEMEF2D software. The obtained results show a very large increase in temperature at the winding. Heat conduction in both radial and axial directions has a very large effect on the temperature value in all regions of the SRM6/4.","PeriodicalId":37704,"journal":{"name":"Serbian Journal of Electrical Engineering","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68754223","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Gorana Gojic, R. Turovic, D. Dragan, Dušan B. Gajić, V. Petrovic
This paper presents an approach to correcting misclassified pixels in depth maps representing parts of the human body. A misclassified pixel is a pixel of a depth map which, incorrectly, has the ?background? value and does not accurately reflect the distance from the sensor to the body being scanned. A completely automatic, deep learning based solution for depth map correction is proposed. As an input, the solution requires a color image and a corresponding erroneous depth map. The input color image is segmented using deep neural network for human body segmentation. The extracted segments are further used as guidance to find and amend the misclassified pixels on the depth map using a simple average based filter. Unlike other depth map refinement solutions, this paper designs a method for the improvement of the input depth map in terms of completeness instead of precision. The proposed method does not exclude the application of other refinement methods. Instead, it can be used as the first step in a depth map enhancement pipeline to determine approximate depths for erroneous pixels, while other refinement methods can be applied in a second step to improve the accuracy of the recovered depths.
{"title":"Automatic corrections of human body depth maps using deep neural networks","authors":"Gorana Gojic, R. Turovic, D. Dragan, Dušan B. Gajić, V. Petrovic","doi":"10.2298/sjee2003285g","DOIUrl":"https://doi.org/10.2298/sjee2003285g","url":null,"abstract":"This paper presents an approach to correcting misclassified pixels in depth maps representing parts of the human body. A misclassified pixel is a pixel of a depth map which, incorrectly, has the ?background? value and does not accurately reflect the distance from the sensor to the body being scanned. A completely automatic, deep learning based solution for depth map correction is proposed. As an input, the solution requires a color image and a corresponding erroneous depth map. The input color image is segmented using deep neural network for human body segmentation. The extracted segments are further used as guidance to find and amend the misclassified pixels on the depth map using a simple average based filter. Unlike other depth map refinement solutions, this paper designs a method for the improvement of the input depth map in terms of completeness instead of precision. The proposed method does not exclude the application of other refinement methods. Instead, it can be used as the first step in a depth map enhancement pipeline to determine approximate depths for erroneous pixels, while other refinement methods can be applied in a second step to improve the accuracy of the recovered depths.","PeriodicalId":37704,"journal":{"name":"Serbian Journal of Electrical Engineering","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68753752","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The authors of the paper entitled "Pendulum test: Quantified Assessment of the Type and Level of Spasticity in Persons with Central Nervous System Lesions", Dejan B. Popovic and Tadej Bajd, informed the Editor about necessary correction of the paper.
题为“钟摆试验:中枢神经系统病变患者痉挛类型和程度的量化评估”的论文作者Dejan B. Popovic和Tadej Bajd通知了编辑对论文的必要修改。链接到更正文章10.2298/SJEE171204006P
{"title":"Corrigendum on: Pendulum test: Quantified assessment of the type and level of spasticity in persons with central nervous system lesions [Serb. Jour. of Elect. Eng., Vol. 15, no. 1, feb. 2018, pp. 1 - 12]","authors":"E. Editorial","doi":"10.2298/sjee2002257e","DOIUrl":"https://doi.org/10.2298/sjee2002257e","url":null,"abstract":"The authors of the paper entitled \"Pendulum test: Quantified Assessment of the Type and Level of Spasticity in Persons with Central Nervous System Lesions\", Dejan B. Popovic and Tadej Bajd, informed the Editor about necessary correction of the paper. <br><br><font color=\"red\"><b> Link to the corrected article <u><a href=\"http://dx.doi.org/10.2298/SJEE171204006P\">10.2298/SJEE171204006P</a></b></u>","PeriodicalId":37704,"journal":{"name":"Serbian Journal of Electrical Engineering","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68753991","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
H. Azizi, M. Chebout, H. Moulai, A. Bréard, C. Vollaire
Generally, most of the electronic equipments need a metallic enclosure in order to mechanically protect and electrically shield the interior printed circuit boards (PCBs) and subsystems. But in practical situations, the apertures or slots of various forms are essential parts of the shielding enclosure for thermal dissipation, CD-ROMs, connectors, I/O cabling and so on. The performance of shielding enclosures for high-speed digital systems is compromised by these inevitable discontinuities on enclosure. To minimize the electromagnetic interferences and susceptibility risks by these discontinuities, the shielding enclosures with apertures should be designed based on thorough analysis about the electromagnetic coupling mechanism through apertures. In this paper, the effect of apertures and oblique incident plane wave on shielding effectiveness of the enclosure is studied with the Circuital Approach, and the Finite-Difference Time-Domain (FDTD) method, the simulated SE data are verified by experimental technique. Good agreements are found between these approaches.
{"title":"Analytical and numerical models compared with measurements for analysis of electromagnetic radiation through apertures of a metallic enclosure","authors":"H. Azizi, M. Chebout, H. Moulai, A. Bréard, C. Vollaire","doi":"10.2298/sjee2002131a","DOIUrl":"https://doi.org/10.2298/sjee2002131a","url":null,"abstract":"Generally, most of the electronic equipments need a metallic enclosure in order to mechanically protect and electrically shield the interior printed circuit boards (PCBs) and subsystems. But in practical situations, the apertures or slots of various forms are essential parts of the shielding enclosure for thermal dissipation, CD-ROMs, connectors, I/O cabling and so on. The performance of shielding enclosures for high-speed digital systems is compromised by these inevitable discontinuities on enclosure. To minimize the electromagnetic interferences and susceptibility risks by these discontinuities, the shielding enclosures with apertures should be designed based on thorough analysis about the electromagnetic coupling mechanism through apertures. In this paper, the effect of apertures and oblique incident plane wave on shielding effectiveness of the enclosure is studied with the Circuital Approach, and the Finite-Difference Time-Domain (FDTD) method, the simulated SE data are verified by experimental technique. Good agreements are found between these approaches.","PeriodicalId":37704,"journal":{"name":"Serbian Journal of Electrical Engineering","volume":"17 1","pages":"131-148"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68753435","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Microwave and millimeter-wave communication systems require couplers in different applications. The aim of this paper is to construct simple wave digital models of directional couplers with two or three parallel lines. The idea behind this aim is to be able to model a microstrip structure and to simulate it using Simulink platform which has already been used extensively by researchers. Advanced Design System (ADS) software and MATLAB/Simulink environment are used to design, implement and simulate the investigated microstrip circuits and their models. Validity and accuracy of the presented digital models are fully demonstrated through several benchmark problems.
{"title":"Wave-based digital models of different branch-line couplers","authors":"B. Stošić","doi":"10.2298/sjee2002149s","DOIUrl":"https://doi.org/10.2298/sjee2002149s","url":null,"abstract":"Microwave and millimeter-wave communication systems require couplers in different applications. The aim of this paper is to construct simple wave digital models of directional couplers with two or three parallel lines. The idea behind this aim is to be able to model a microstrip structure and to simulate it using Simulink platform which has already been used extensively by researchers. Advanced Design System (ADS) software and MATLAB/Simulink environment are used to design, implement and simulate the investigated microstrip circuits and their models. Validity and accuracy of the presented digital models are fully demonstrated through several benchmark problems.","PeriodicalId":37704,"journal":{"name":"Serbian Journal of Electrical Engineering","volume":"17 1","pages":"149-169"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68753463","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The authentication algorithm for machine-to-machine communication devices via the MQTT Protocol is considered, which allows verifying the device legality without sending the password. The algorithm protects the Internet of things network from unauthorized access, ensures confidentiality by generating a common session key, and provides protection against attacks of the "man in the middle" and others. The obtained experiment results showed noticeable performance improvement compared to the TLS Protocol. The cryptographic strength of the proposed algorithm is based on the discrete logarithm problem. The main advantage of the algorithm is the ability to authenticate in one requestresponse cycle.
{"title":"Authentication algorithm for internet of things networks based on MQTT protocol","authors":"D. Dikii","doi":"10.2298/sjee2003389d","DOIUrl":"https://doi.org/10.2298/sjee2003389d","url":null,"abstract":"The authentication algorithm for machine-to-machine communication devices via the MQTT Protocol is considered, which allows verifying the device legality without sending the password. The algorithm protects the Internet of things network from unauthorized access, ensures confidentiality by generating a common session key, and provides protection against attacks of the \"man in the middle\" and others. The obtained experiment results showed noticeable performance improvement compared to the TLS Protocol. The cryptographic strength of the proposed algorithm is based on the discrete logarithm problem. The main advantage of the algorithm is the ability to authenticate in one requestresponse cycle.","PeriodicalId":37704,"journal":{"name":"Serbian Journal of Electrical Engineering","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68753783","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：