Volume 5, Issue 2, 2020.

Overview of Security Threats, Prevention and Protection Mechanisms in Wireless Sensor Networks

Nemanja RADOSAVLJEVIĆ, Đorđe BABIĆ

As global concerns about the security and privacy of data grow from day to day, the question of their transmission through different types of networks arises. The security issue is especially important for wireless sensor networks (WSNs) because of their architecture. WSNS consist of many small sensors which collect and transmit data. In wireless sensor networks, only a few nodes have a base station role. This paper will outline the basic issues related to security threats and the mechanisms used to prevent security breaches of WSNs.

Web Applications Protection from Automated Attacks by the reCAPTCHA API

Zoran VELIČKOVIĆ, Zoran MILIVOJEVIĆ

This paper presents the integration of Web page protection against malicious automated software attacks on HTML forms. Malicious software imitates human work in HTML form and thus causes problems in the functioning of the Web page. That is why it is extremely important to prevent automated software from accessing HTML forms. The practical part of the paper integrates the free Google technology – reCAPTCHA, which determines whether the form was accessed by a human or automated software. The Web API developed by Google is used to integrate reCAPTCHA into the Web page. The analysis of reCAPTCHA test results is performed on the server side of the Web application using a PHP script. Easy integration and reliable test recommend reCAPTCHA technology for use in highly reliable Web sites to protect against automated software attacks.

Application of Data Mining in Patent Portfolio Technology Analysis

Sandra NEMET, Dragan KUKOLJ, Norbert NEMET

The paper deals with development of simple and easily applicable automatic procedures for quick identification of technologically similar business entities. Both procedures consist of text processing and dimension reduction steps. However, the procedures are distinguished by the used information source and how the text mining process is carried on. The first approach uses text from the first independent claim as input, processed with the neural network learning-vector algorithm. In contrast, the second approach uses only international patent codes as inputs and processes them with term frequency-inverse document frequency algorithm. Both procedures are developed and verified on the patent portfolio created for start-ups with patented technologies in the domain of AI-based autonomous driving. Comparison of technology spaces generated by the presented procedure show compatible similarities between the same entities.

Stego-Objects Metrics Improvement Using the Method of Minimal Decimal Difference in Spatial Image Steganography

Predrag MILOSAV, Milan MILOSAVLJEVIĆ, Zoran BANJAC

This paper deals with the improved method of spatial image steganography – Minimal Decimal Difference Method. The basic LSB method, as a starting point, was improved, an implementation algorithm was proposed and developed, and then measurements were made and results were processed. The benefits achieved by the advanced method in comparison with the classical LSB (Least Significant Bit) method are presented graphically and numerically and further research and development is proposed in order to achieve even better results.

Magnetic Field Distribution in Vicinity of Mixed Power Line Towers

Karolina KASZÁS-LAŽETIĆ, Teodora GAVRILOV, Gorana MIJATOVIĆ, Kristian HAŠKA, Miroslav PRŠA

The paper presents a comparative analysis of magnetic field distribution in the vicinity of the overhead mixed power line, suspended by steel lattice and reinforced concrete towers. The main goal of the paper is to examine the effect of induced currents in ferromagnetic, conductive parts of towers on magnetic field distribution. The whole calculation was carried out applying COMSOL Multy­phisics program package, based on the finite element method. The calculated results show that due to induced currents in all ferromagnetic, conductive parts of the towers, the magnitude of the magnetic flux density vector decreases around the towers. The event is more significant in the vicinity of steel lattice towers then around armour concrete towers.