University of Niš: Facta Universitatis (E-Journals) / Универзитет у Нишу
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COMPARATIVE PERFORMANCE ANALYSIS OF HARDWARE AND SOFTWARE AES ENCRYPTION IMPLEMENTATION IN WSN
Full text linkWireless Sensor Networks (WSNs) have been among the most researched areas in the last ten or twenty years. Different sensor technologies and wireless communication contributed to the progress in this field, but two features of these systems are still insufficiently developed. These are data security and energy consumption. Data is particularly vulnerable during transmission, whether it is communication between nodes or between a base station and a server. One of the most promising solutions for this problem is data encryption. However, data encryption negatively affects sensor nodes' energy consumption, so there is a compromise between data security and energy consumption. Symmetric encryption algorithms are more effective than asymmetric for these applications. Advanced Encryption Standard (AES) is the most frequently used symmetric algorithm. This paper analyzes the performance of hardware and software implementation of the AES encryption algorithm on the sensor node. The hardware implementation is based on the integrated circuit ATECC608A, while the microcontroller firmware includes the software implementation. The analyzed parameters include execution time, energy consumption, and memory usage, for four working frequencies (8 MHz, 16 MHz, 32 MHz, and 64 MHz), and different supply voltages (2.6 V, 3.3 V, and 5 V). The results show that the hardware implementation works faster for the lower working frequency (up to 12 MHz). The execution time of software implementation is reduced approximately 50 % with doubled frequency, while the reduction is less, and inconstant in hardware implementation. The hardware implementation consumes more energy that software, and the difference rises with the working frequency. These differences are 20 %, 40 %, 60 %, and 75 % at the same frequencies considered for execution time analyzing. The hardware implementation occupies 4.58 % of the memory of the microcontroller (PIC18F45K22), while 10.13 % is needed for the software implementation. These results can provide a good starting point for choosing an appropriate encryption implementation method
CENTRAL INDEX ORIENTED SOME GENERALIZED GROWTH ANALYSIS OF COMPOSITE ENTIRE FUNCTIONS
Full text linkIn this paper, we have discussed some different growth properties of composite entire functions on the basis of their central index using the concepts of (p,q,t)L-th order and (p,q,t)L-th type
APPLICATION OF GENERALIZED WEAK CONTRACTION IN PERIODIC BOUNDARY VALUE PROBLEMS
Full text linkThe main aim of this research article is to formulate some fixed point andcoupled fixed point results under generalized weak contraction on Re−metric spaces.As an application, we obtain the solution for periodic boundary value problems andalso give an example to demonstrate the applicability of our results. The obtain resultsgeneralize and improve several well-known results in the existing literature
EMBEDDING AND WEIGHTING OF WEBSITE FEATURES FOR PHISHING DETECTION
Full text linkOne of the most common cyber threats are phishing attacks. During a phishing attack, attackers use various technical and social engineering tricks to try to lure victims to a phishing website. The website looks like it belongs to a trusted organization but is actually run by the attackers and used to mislead victims into revealing their passwords, credit card numbers, or other confidential information. In this paper, we use discrete descriptive website features to detect whether a website is phishing or legitimate. We create a customized embedding layer specifically designed for these types of features, as well as an embedding weighting mechanism that we later apply. We propose a convolutional neural network-based model for phishing website detection and demonstrate its efficacy on three datasets. With accuracy rates of up to 97.56%, the model performed on par with or better than the current state-of-the-art approaches on each dataset
COMPARISON OF NONCLASSICAL CONTROLLERS ON NONLINEAR VIBRATIONS ANALYSIS OF PIEZOELECTRIC NANORESONATOR
Full text linkIn current work, semi nonclassical controller effects such as strain gradient (SGT), nonlocal (NLT) and Gurtin–Murdoch surface/interface (GMSIT) theories are presented for analyzing of nonlinear vibration in piezoelectric nanoresonator (PENR) compared to classical theory (CT). PENR subjected to nonlinear electrostatic excitation with direct (DC) and alternating (AC) voltages and also visco-pasternak medium. For this analysis, Hamilton’s principle, Galerkin technique, combination of Complex averaging method and arc-length continuation are used to analyze nonlinear frequency response and stability analysis of PENR. The results show that ignoring small-scale and surface/interface effects give inaccurate predictions of vibrational response of the PENR. It is indicated that in different boundary condition, material length scale and nonlocal scale parameters respectively lead to decreasing and increasing of PENR stiffness and also the amplitude of oscillation and the range of instability of non-classic theories of NLT and SGT are greater than that of the classical one. Also changes of surface/interface parameters lead to decreasing or increasing the dimensionless natural frequency, resonant frequency, resonance amplitude, nonlinear behavior and the system's instability of PENR
DEFICIT U PROMENI PRAVCA KRETANJA I DRIBLINGU U FUDBALU: POSTOJE LI RAZLIKE U ZAVISNOSTI OD STAROSNE KATEGORIJE?
No full textChange of direction (COD) and technical skills are considered key parameters of performance in youth soccer, as they are highly demanded during a match. The aim of this study was to examine whether change of direction and Dribble deficit (DD) differ between younger soccer players from various consecutive age categories. Ninety young soccer players (mean age: 11.67 ± 1.29 years; body height: 154.84 ± 10.82 cm; body weight: 43.95 ± 9.62 kg) participated in the study and were divided into 5 age categories (Under 10, Under 11, Under 12, Under 13, and Under 14). All the participants performed change-of-direction tests (the Slalom and Zig-zag) with and without a ball. The DD is determined indirectly by reducing the time variation between the fastest trials with and without a ball. The results revealed that the U14 group is significantly better in the Slalom with and without a ball compared to the other groups, in the Slalom DD compared to the U12 group, and Zig-Zag DD compared to the U13 group (p < 0.05). On the other hand, as expected, the U10 group showed the lowest results, with the Slalom test results significantly lower compared to the other categories (p < 0.05). In conclusion, as was expected, the oldest group (U14) showed better results in both COD tests and in DD compared to their younger peers, with the youngest group (U10) exhibiting the lowest values in almost all the tests.Promena pravca kretanja (COD) i tehničke veštine se smatraju ključnim parametrima mladih fudbalera, jer jer se često ispoljavaju tokom utakmice. Cilj ove studije bio je da utvrdi da li se parametri promene pravca kretanja i dribbling deficita razlikuju kod mladih fudbalera uzastopnog godišta. Devedeset mladih fudbalera (mean godine: 11.67 ± 1.29; visina tela: 154.84 ± 10.82 cm; masa tela: 43.95 ± 9.62 kg) koji su bili podeljeni u pet staronih kategorija je učestvovalo u ovoj studiji. Svaki ispitanik je uradio Slalom i Cik-cak test sa i bez lopte. Dribling deficit je indirektno izračunat tako što je ostvareno vreme na testu sa loptom oduzeto od ostvarenog vremena na istom testu ali bez lopte. Rezultati su pokazali da je grupa U14 značajno bolja u slalomu sa i bez lopte u odnosu na sve ostale grupe kao i u dribbling deficitu slalom testa u odnosu na grupu U12 (p < 0.05). S druge strane, očekivano, grupa U10 pokazala je najslabije rezultate, sa značajno nižim vrednostima na slalom testu u odnosu na sve ostale kategorije (p < 0.05). Zaključak je da je najstarija grupa (U14) pokazala bolje rezultate u testovima promene pravca kretanja i u parametrima dribbling deficita u odnosu na svoje mlađe vršnjake, pri čemu je najmlađa grupa (U10) pokazala najniže vrednosti u skoro svim testovima
TRIBO-MECHANICAL CHARACTERIZATION OF ENB ALLOY COATINGS: EFFECT OF HEAT-TREATMENT TEMPERATURE AND SODIUM BOROHYDRIDE CONCENTRATION
Full text linkPreviously electroless Ni-B (ENB) coatings were analyzed and optimized based on various coating parameters. However, variation of nano-indentation behaviour like nano-hardness, elastic modulus and scratch hardness variation with bath composition and heat treatment temperature has not been reported earlier. An attempt has been made to explore the same in the present study. ENB coating layers are deposited on AISI 1040 steel specimen with varying concentration of sodium borohydride (NaBH4) and heat-treated at 350°C, 450°C and 550°C to investigate the related effects. Nano-hardness and elastic modulus of as-coated specimens are found to improve with NaBH4 concentration due to increased boron content and nodule size. Both nano-hardness and elastic modulus are observed to improve further upon heat treatment because of incorporation of various boride phases leading to compact morphology and increased size of the nodules. Scratch hardness value also increases with NaBH4 concentration and it improves further upon heat treatment and reaches to its maximum at 450°C due to presence of compact and hard Ni2B phase. Compact homogeneous surface morphology enhances the friction and wear behaviour of the heat-treated coatings even though surface roughness deteriorates after heat treatment.
A NEW FRAMEWORK FOR RISK ASSESSMENT OF ROAD TRANSPORTATION OF HAZARDOUS SUBSTANCES
Full text linkVarious elements including environmental, public safety, economic, and security concerns define the evaluation of threats connected with the movement of dangerous materials. It is imperative to undertake a comprehensive investigation to address the multifaceted problem of risk assessment concerning the road transportation of dangerous materials. The primary aim of this study is to present a framework for threat assessment in this domain. To achieve this objective, an integrated approach involving stepwise weight assessment ratio analysis (SWARA) with the multi-attributive border approximation area comparison (MABAC) approach under the Z-number theory is introduced. Preliminary investigations and expert opinions are taken into consideration, and 17 risks are identified for developing the failure mode and effect analysis (FMEA) technique for rural roads located in Cosenza, a region in southern Italy. A qualified analysis is conducted between the outcomes of the FMEA approach implemented by Z-SWARA-MABAC and those of the conventional FMEA method. This investigation is undertaken to achieve sustainable mobility goals by evaluating the risks and enhancing the safety of the transportation of dangerous substances via roadways. Therefore, it is essential to re-evaluate the laws and measures required to mitigate hazards on the regional road network of southern Italy
BF-Ostrowski Type Inequalities for (A, B, G, D)-convex
Full text linkIn this paper, we present the very first time the generalized notion of (A,B, G,D)−convex (concave) function in mixed kind, which is the generalization of functions given in [15], [2], [4], [14], [16] and [3]. We would like to state well-nown Ostrowski inequality via Fuzzy Riemann Integrals for (A,B, G,D)− convex (concave) function in mixed kind. Moreover we establish some Fuzzy Ostrowski type inequalities for the class of functions whose derivatives in absolute values at certain powers are (A,B,G,D)-convex (concave) functions in mixed kind by using different techniques including H¨older’s inequality [27] and power mean inequality [26]. Also, various established results would be captured as special cases with respect to convexity of function
QUALITATIVE ANALYSIS OF SOLUTIONS FOR A TIMOSHENKO TYPE EQUATION WITH LOGARITHMIC SOURCE TERM
Full text linkThis paper deals with a Timoshenko type equation with strong damping andlogarithmic source terms. The global existence and the decay estimate of the solutionshave been obtained. We reproduce the finite time blow up results of weak solutions bythe combining of the concavity method, perturbation energy method and differential–integral inequality technique. These results extend and improve some recent results inlogarithmic nonlinearity