Periodicals of Engineering and Natural Sciences (PEN - International University of Sarajevo)
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A Comparative Survey on Wireless Internet Usage and Future Expectations of University Students (The Cases of USF, AKU and IUS)
Get PDFIn this article, college students’ internet usage and the expectations for better wireless access are discussed. Wirelessand mobile internet access recently became an integral part of our lives. Especially, with the introduction of smartdevices (phones, tablets etc.) into the wireless market and the vast number of applications running on these devices,we end up being addicted to them. Now, some of us have come to a point where we can leave everything behind usexcept our phones. To better understand how the wireless access has influenced us we conducted a face-to-facesurvey with three different groups of college students totalling 829. According to the survey, there are some problemswhile using the internet, such as internet speed and connection. University students do not want to give up mobilecommunications and they never want to be secondary users. They pay more attention to security and privacy incommunication. They are also awaiting functional innovations in the future
Detailed Analysis of a 3 dB Microstrip Hybrid Coupler
Get PDFThe paper depicts a symmetric microstrip coupler designed for WiMax applications in the frequency range of 2.32 - 2.52GHz. The proposed coupler is comprised of four resonator structures attached in parallel to the ports providing lowered isolation and increased insertion loss and coupling factor. Furthermore, the presented microstrip coupler is simulated utilizing the Sonnet Suites software with the numerical approximation of the mathematical derivation of MoM (Method of Moments) for the symmetrical structure. The simulated and fabricated results show high resemblance with the data acquired after the simulation with input match being below -20dB, insertion loss and coupling factor almost -3.0 dB and isolation factor below -50dB. The approximate values of the measured design are -15.48dB, -3.86dB and -46.63dB respectively Moreover, the dielectric substrate utilized for the proposed geometry of the microstrip coupler is FR4 with εr=4.4 with thickness of 1. 55mm.The proposed coupler is relatively inexpensive, reliable in the provided frequency range and could be used in wireless communication applications
Artificial intelligence technologies as a means of improving the digital literacy of future teachers
Get PDFThis study aimed to find out whether artificial intelligence (AI) technologies can improve digital mastery among in-training educators in Kazakhstan. It determines the rate of adoption of AI tools, evaluates their role in enhancing digital competencies, and examines the associated challenges and opportunities. Mixed-method approach was employed, which began with a quantitative phase (pre- and post-intervention tests) and concluded with a qualitative phase (interviews). The survey sample comprised 385 participants while 80 participants (40 each) made up the intervention consisting of traditional instruction and AI integrated instruction (ChatGPT and Google Cloud AI). The result showed that prior the intervention, all participants showed low digital literacy and did not adopt AI. However, a 100% AI adoption rate was observed after the intervention, with 75% having moderate to 25% high digital literacy. A paired t-test found significant improvements in digital literacy (M = 25.34 to 35.32, t(19) = 2.12, p < 0.05) and AI proficiency (M = 19.89 to 30.21, t(19) = 1.03, p < 0.05). Lack of institutional support, tool unfamiliarity, and skepticism were some of the problems people encountered. Conversely, the problems with digitally competent users were informed reflection and pedagogic balance. Despite these challenges, both groups recognized the possibilities of individual learning, better classroom result, and team development. Conclusively, targeted AI interventions in teachers training will greatly improve pre-service teacher\u27s digital literacy. Therefore, when applied, close monitoring and ethical strategies should be put in place to enhance academic integrity
Flux Switching Permanent Magnet Generator Design and Optimization Using Response Surface Methodology
Get PDFFlux Switching Permanent Magnet Generators (FRPMGs) have been used increasingly in direct drive variable speed wind turbines due to their merit such as their high torque density, easy flux weakening operation and robust rotor structure. Generally, the quality of output power in direct drive systems is lower than multi stage fixed speed systems, because of removing the gears, so it’s important to design these kinds of generators with low ripple and lowest harmful harmonics and cogging torque. This aim is one of the most important terms in increasing the quality of output power of generator simultaneously with back-EMF improvement. The objective of this paper is introducing a simple design method and optimization of high power FRPMG applied in direct drive wind turbine system by lowest possible amplitude of cogging torque and highest possible power factor, efficiency and power density. For optimization reason an optimum method called combined response surface methodology (RSM) and design of experiment has been applied. Also in order to extract the output values of generator and sensitivity analysis for design, 2D-Finite element model, was used. This method has high accuracy and gives us a better insight of generator performance and presents back EMF, cogging torque, flux density and FFT of the FSPMG. This study can help in design approach of such machines
A model of particles movement on a discrete contour
Get PDFWe study an exclusive process on a circle. In this paper, we study a discrete closed contour, containing N cells and M particles. Each particle occupies a cell at every time. There is not more than one particle in each cell at every moment. At every time t=0,1, 2, … , each particle tries to move onto a cell forward with probability p, this particle tries to move back with probability q, and the particle does not try to move with probability s, p+q+s=1. Under assumptions that q=0, the system of this type was considered by M. Kanai et. al. As it follows from results of these authors, in the case q=0, the process is time reversible, i.e., in the stationary state, the behavior of process does not change if the direction of time-axis is changed. The ergodic properties of some more general exclusive process were studied by M. Blank but, in the case 0<p, q<1, values of steady probabilities have not been found. Under the assumptions that M=2, N=2, s=0, we have obtained a formula for the average velocity of particles and the particle transitions intensity. In this paper, under assumptions that M=2, it has been proved the following. The process is time-reversible if M=2, N is even and s=0. The process is not time-reversible if M=2, s>0, or N is odd and s=0. We have proved that the process can be non-reversible if M ≥ 3, s=0
Knowledge flow analysis: the quantitative method for knowledge stickiness analysis in online course
Get PDFThe aim of this study is to better understand the feasibility of using technological solutions to detect specific knowledge descriptors in online learning systems. Understanding the relevance of specific knowledge in the context of online courses is important for the architecture of the content of the course and for improving the effectiveness of the learning process. By identifying the specific nature of the knowledge flow in a timely manner, it is possible to better adapt the course content to the needs of the student and to ensure that the time spent on learning is used effectively. In the case of this tailored course content, it is expected that in a given course, it would be possible to learn more content than a time-like course where knowledge stickiness has not been taken into account. By using calculations and excluding the possibility of a subjective view as far as possible, authors are clarifying the nature of knowledge for each of the competencies. Automated evaluation of knowledge properties would significantly facilitate the learning process by allowing better management of the knowledge flow. Improving the effectiveness of preparing training materials would be a significant benefit from the development of such a solution
News on Modeling of Walking Robot Critical Positions
Get PDFThe principal objective of our study is to emphasize the strategies for the walking robot mathematical model to traverse an uneven terrain, respecting the hypothesis of environment model defined by us. The multiple aspects on axiomatic systems, with possible application to environment’s mathematical model axiomatization, open an interesting new way of research and is exposed in the first part of the paper. Our study on the walking robot begins with formulation of improved mathematical model for physical identification derived from geometrical identification of critical position in particular case of waking robot leg. The physical identification of the critical position is analyzed in the paper on our concrete case of walking robot leg mathematical model. The specialized algorithm performed by us is used for verification of the theory. The new directions of research, opened by our analyses in this area, are described
Accurate targeting in robot-assisted TCM pulse diagnosis using adaptive sensor fusion
Get PDFAccurate targeting plays an important role in the study of human-robot interaction under dynamic environments. Especially for robot-assisted Traditional Chinese Medicine (TCM) pulse diagnosis, the localization and accuracy of diagnose positions at wrist needs to be addressed. In this work, imaging photoplethysmography (iPPG) which measures the physiological changes of blood flow in artery is used as an extra modal information in addition to computer vision at localization, to alleviate the effect of approaching distance varying during the robot arm movement. Both computer vision and iPPG are fed into an adaptive fusion expert of convolutional neural networks (CNN) architecture, and this boosts the accuracy at targeting of TCM radial artery at wrist. A coherence weight of their contributions was calculated and reflected the adaptation of the CNN to distance varying
A mathematical model of traffic segregation on multilane road
Get PDFWe study a process of segregation of traffic flow on a multilane highway. Our study is based on the stochastic mathematical model developed by Buslaev A.P. et al. in 2006, 2008 years. This model is based on the deterministic-stochastic approach that was developed by Buslaev in 2005. In the model, particles, moving on a lattice, correspond to vehicles. We consider the problem of optimization of segregation characteristics. We consider an example of segregation process on five-lane segment of a road. The length of the segment equals 4000 meters. The calibration of the model parameters is based on empirical data obtained in measurements on roads
Digitalization of Ukraine’s economy as a factor in strengthening regional development resilience
Get PDFDigitalization is now considered as necessary for strengthening development and resilience of any nation. The present study examined the role of digitalization in regional economic resilience in Ukraine in the scenario of disruption and displacement. The study utilized comparative cross-regional dataset. The analysis evaluated variations in digital infrastructure and business-facing e-services in various regions of Ukraine. It also examined other factor than can help in recovery and enhancing resilience. Those factors included SME continuity, employment stability and logistics restoration. Quantitative tables summarized differences in the availability and uptake of e-services for permitting, taxation, reporting and supply-chain coordination. Further, the qualitative interviews with regional administrators and firm representatives provided evidence of operational mechanisms. The first and most notable finding is the very strong positive correlation (r = 0.87, p < 0.01) between the Digitalization Index and the Resilience Index; between E-service uptake and Firm continuity (r = 0.82, p < 0.01). The strong positive correlation confirmed that digitalization intensity was closely associated with post-shock economic recovery at the regional level. The findings indicated those regions with higher levels of digital readiness and specially those offering comprehensive online business registration, reporting and logistics platforms demonstrated faster recovery of enterprise activity and more stable supply flows. However, the areas with limited digital access or low administrative capacity faced longer recovery times and greater firm attrition. The results suggest that digitalization is needed for the structural resilience and it helps in enabling administrative continuity and business reactivation without physical presence.