Periodicals of Engineering and Natural Sciences (PEN - International University of Sarajevo)
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Monthly drought monitoring of the surface water area of Sawa Lake, Iraq during 2016-2022 using remote sensing data
Get PDFDrought is a common phenomenon in Iraq\u27s environment, and the country has experienced severe drought events exacerbated by the threat of climate change (low rainfall and high temperatures) over the past two decades. Iraq is located in a semi-arid region whose water resources have been restricted and mostly shared with its neighbours. To investigate the effect of drought on the surface water area of Sawa lake, we analysed 52 Sentinel-2 images from May 2016 to July 2022 using an open-source SNAP toolbox to map the boundary of the surface-water body of the lake. The results indicate that the surface water area of Sawa lake has de-creased significantly over the last six years with the most extreme decline beginning in May 2021, when the area of the lake lost about 51% of its initial size (May 2016). By March 2022, the lake had disappeared and about 96% of the water\u27s surface area had been lost. To better understand the potential causes of droughts, further analysis has been conducted on the effects of precipitation and human activities (vegetation cover and Al-Samawah saltpan for salt production) on the lake. Investigations revealed that the rapid expansion of agricultural areas around the lake by 254% and the increase in salt production from the Al-Samawah saltpan by about 121% are among the direct causes of the drought. In addition, the results of the statistical test anal-ysis between the estimated surface water area of Sawa lake and human activities were significant at a 95% level of confidence. The findings of this study can assist decision-makers to understand the interaction be-tween human activities and the lake\u27s environment to design a strategic plan for lake recovery and a sustain-able water resource management system in southern Iraq
Bitcoin prediction with a hybrid model
Get PDFIn recent years, Bitcoin has become the most widely used blockchain platform in business and finance. The goal of this work is to find a viable prediction model that incorporates and perhaps improves on a combina-tion of available models. Among the techniques utilized in this paper are exponential smoothing, ARIMA, artificial neural networks (ANNs) models, and prediction combination models. The study\u27s most obvious discovery is that artificial intelligence models improve the results of compound prediction models. The sec-ond key discovery was that a strong combination forecasting model that responds to the multiple fluctua-tions that occur in the bitcoin time series and Error improvement should be used. Based on the results, the prediction accuracy criterion and matching curve-fitting in this work demonstrated that if the residuals of the revised model are white noise, the forecasts are unbiased. Future work investigating robust hybrid model forecasting using fuzzy neural networks would be very interesting
The impact of using mobile apps on student engagement and involvement in the learning process
Get PDFFor modern education, mobile applications are actively becoming a key tool. They help increase student engagement and activity by providing access to educational materials, organizing time, completing tasks, and thus stimulating motivation. At the same time, mobile applications can adapt learning methods to the individual needs of each student. Of course, the use of mobile applications is often accompanied by problems: distraction and technical difficulties. The proposed article aims to analyze the impact of the use of mobile applications on students\u27 academic performance, frequency, characteristics, and overall effectiveness of the learning process to investigate the impact of the use of mobile applications and digital technologies on student activity and involvement in the learning process. Special attention is paid to the context of academic performance. The methodology of the work is a cross-sectional survey. The survey involved 125 students from three universities. The survey results assessed the intensity of students\u27 digital activity, their use of educational platforms, remote interaction, and time spent online for learning. In addition, the results indicate that students do not use mobile applications for in-depth learning but use them only for instrumental purposes. The work implemented a correlation analysis, which showed the absence of a significant impact of digital activity on academic performance. This emphasizes the need for a deeper study of the effectiveness of mobile applications in the learning process
Awareness of investors toward green finance initiatives
Get PDFThe study investigates investors’ knowledge and understanding of green finance initiatives and how these initiatives support environmental sustainability and sustainable development goals (SDGs). In an era of growing global focus on sustainability, knowledge of investor perspectives is critical in moving green finance practices forward. The research uses a one-sample t-test to determine whether investor views on green finance are a catalyst for eco-friendly business and investment strategies based on data from 463 investors. Strong consensus among investors is that green finance can help promote sustainable development through the use of energy efficient production methods, clean energy efforts and lessening environmental impacts. Investors understand that green financial instruments, such as green credits, green banks and specialty funds, perform a function in facilitating environmental responsibility and encouraging the implementation of climate friendly industrial practices. The study also underscores the value of supportive platform and financial incentives, and the incentives for green finance adoption and innovation. Investors are also perceived to increasingly see sustainability integration into investment portfolios as a financial opportunity and as a means to achieve long term environmental goals, the results also show. This paper also concludes the importance of green finance awareness for investors. It urges that green finance initiatives continue to be promoted and integrated into mainstream investment practices to facilitate the global effort in realizing SDGs and promoting sustainable development in all industries
Implementation of artificial intelligence in the system for detecting academic dishonesty in Ukrainian secondary and higher education institutions
Get PDFArtificial intelligence (AI) systems in education and science require special attention due to the rapid development of digitalization. The article aims to determine the effectiveness of modern AI systems based on a comparative analysis of AI methods and to develop scientifically sound prospects for their widespread implementation in Ukrainian education. The author applied the PRISMA scientific approach to achieve the proposed goal, which allowed the selection of the necessary scientific sources (50) and their systematization for further analysis. The results show that natural language processing, latent semantic analysis, word embeddings, stylometry analysis, text analysis and separation, graph methods, and data integrity checks are used to check for dishonesty. These methods are also used to determine the authorship of a text, identify suspicious moments in texts, and detect plagiarism and borrowings. Other modern programs allow you to identify the facts of academic dishonesty and plagiarism, even when the text is paraphrased. The main problem is the possibility of circumventing the main algorithms by changing the structure of the text or generating false positive results. For the modern educational system of Ukraine, it is proposed that a high-quality, clear state strategy be formed, teachers\u27 digital literacy be developed, AI tools be introduced into teaching and teacher training methods, and teachers be trained to use platforms for automated assessment and personalization of learning. The conclusions indicate that this issue will require further updating due to the development of technology.
Evaluation of 316L deposition parameters for the reducing stair-case effect of laminated parts by coaxial laser powder deposition
Get PDFThe time reduction to manufacture tools is a requirement, especially those that due to their operating conditions are subjected to stress, abrasion and wear, as well as having to adapt to new design requirements such as complex shapes and internal cooling channels, which are difficult to machine by conventional processes. In consequence, laminated tools might be a solution, nevertheless, the staircase effect in curved contours appears. This study analyzes the reduction of the staircase effect by coaxial laser deposition of 316L metal powder. Using previously cut sheets with thicknesses of 0.5, 1 and 2 mm, these are stacked to make samples with a 14 mm radius contour. An experiment is then designed, based on Taguchi, to determine the optimal multilayer deposition parameters of the molten metal powder. Parameters such as laser power, overlap, feed rate, substrate thickness and mass flow are considered to determine the lowest roughness measured mechanically and optically. Residual stresses are also analyzed and stacking and deposition strategies are proposed to achieve the desired curvature.
Finally, the staircase effect is reduced and the optimal parameters are obtained, which include higher laser power and feed rate but low mass flow and overlap. In addition, lower roughness is obtained with lower mass flow rate and higher feed rate. Residual tensile stresses are also obtained due to the high cooling rates
A review paper: Blockchain security with IoT devices and deep-learning methods
Get PDFInternet of Things (IoT) is changing the face of modern world by interconnecting billions of devices, transforming human life and revolutionizing innovation in various domains such as healthcare, transportation, and smart cities. However, the widespread deployment of IoT applications is dramatically hindered by the aforementioned remaining challenges, which mostly relate to the security, privacy, and trustworthiness of data. This work also discusses their limitations including: small computing power, use of insecure communication protocols, weak authentication, lack of encryption and susceptibility to Distributed Denial of Services (DDoS) attacks. Blockchains A blockchain is a decentralized, tamper-resistant authority which exhibits high levels of security, which could help solve the mentioned security problems of the IoT ecosystems. Blockchain can provide trust through data immutability, transparency and consensus and hence can be employed to provide security and reliability to IoT communication and storage. But integrating blockchain directly in low-resource IoT systems has certain issues like added latency, increased bandwidth usage and additional computational overhead. The objective of this paper is to present a detailed review of the synergy between the architecture of blockchain, the IoT systems and deep learning techniques, and the way that they can be collaboratively utilized for improving data security, trustworthiness, and decision-making in IoT networks. Specifically, we examine existing blockchain-based deep learning frameworks by categorizing them based on four major criteria: blockchain type (public, private, consortium), deep learning approach (e.g., CNN, GAN, DRL), consensus protocols, and datasets used for model training and validation. Furthermore, the paper analyzes the strengths and limitations of these integrated frameworks in addressing real-world IoT challenges. The review highlights how blockchain enhances the trustworthiness and traceability of deep learning outputs, while deep learning models can contribute to intelligent threat detection, adaptive control, and data-driven automation in IoT networks. Finally, we outline current research gaps and propose future research directions that focus on optimizing blockchain-deep learning frameworks for scalability, energy efficiency, and real-time performance in large-scale IoT deployments
Impact of international educational projects on e-learning in Ukraine: experience, challenges and prospects
Get PDFAs a result of Ukraine\u27s integration into the European educational space, research into the impact of international educational cooperation on the transformation of general secondary education institutions has become topical. The existing scientific gap lies in the insufficient number of studies on how elements of the education system change as a result of participation in international programs. The study aims to determine the impact of international educational projects (Erasmus+, eTwinning, Tempus) on the digitalization of education, pedagogical practices, and management strategies. A mixed paradigm was used: at the quantitative stage (n = 60), ANOVA and multiple linear regression were used to assess the relationship between participation in projects and the level of institutional modernization (IMOS). For quantitative analysis, 60 general secondary education institutions (GSEIs) were selected and divided into three subgroups (based on their level of participation in international educational programs). At the qualitative stage, a thematic analysis of 15 interviews and 12 reports was conducted, yielding over 200 open codes. ANOVA revealed significant differences between groups (F(2, 57) = 19. 82, p < 0.001), and the regression model (R² = 0.73) confirmed the significance of the number of projects (β = 4.86, p < 0.001) and the proportion of digital classrooms (β = 0.37, p < 0.001). Four key themes of change were identified: digital innovation, transformation of the teacher\u27s role, modernization of management, and barriers. Hence, the proposed study contributes to understanding the role of international educational cooperation in transforming the national education system.
Analysing courtyards in vernacular farmhouses through space syntax analysis
Get PDFThe Maltese Islands’ domestic spaces have evolved over time, with each iteration aiming to reflect and respond to the cultural and social context of its era. This study examines the connection between domestic space and inhabitant behaviour through the lens of the traditional Maltese farmhouse, a key vernacular dwelling typology that embodies local architectural identity. Building on research in the literature, this study focuses on four case studies. This typology is characterised by a functional design responsive to its surroundings, featuring a central courtyard that serves as both a climate-moderating tool and a social gathering space. This space provides for natural ventilation and serves as a social hub for the residents; it is a space that serves both for gathering and communication and as a point of connection between other spaces within the domestic network. Focusing on the courtyard, this study offers insights into how this space mediates social activity, informs perceptions of the dwelling, and affects movement through it, reflecting the broader relationship between space and community life. This study reveals broader insights into how spatial arrangements and social dynamics influence and mirror one another
Particulate composites, analysis techniques and applications
Get PDFThe combination of at least two of the metal, ceramic or polymer groups at a macro level is called a composite material and, in this way, better properties are obtained. Composites can be partitioned into three groupings as layered, fiber and particle reinforced. Particulate composites offer flexibility in composition and component design and are isotropic. This investigation critically examines analysis techniques for particulate composites such as dimensional measurements, property distribution, composition and phase tests, density, and porosity tests (e.g. Archimedes, Pycnometer), hardness measurements (e.g. Brinell, Rockwell), mechanical properties through non-destructive and destructive testing (e.g. tensile, impact). In addition, application areas of particulate composites are highlighted, including Al-SiC composites for aircrafts, cemented carbides for tool metals, dental porcelain, electrical contacts, friction products, and thermal materials