Metallurgical and Materials Engineering (E-Journal)
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Mathematical Modeling of Turbulent Flows Using Advanced Computational Fluid Dynamics Techniques
Get PDFThis research investigates the application of advanced Computational Fluid Dynamics (CFD) techniques in the mathematical modeling of turbulent flows. The accuracy is improved in different engineering systems by using different turbulence models: the k-ε, k-ω, LES and DNS. The main purpose was to investigate fluid flow behavior in industrial, aerospace, biomedical applications. Results of the experimental data are compared with the k-ε model and show that the average deviation is 5.2% when compared to the experimental data of turbulent boundary layers. Dynamic vortex simulations using the LES model resulted in a 12% decrease in error compared to original results. In addition, the DNS model was close to obtaining near exact solutions at the price of greatly increased CPU costs, with a deviation of 1.4% in highly turbulent cases. It was found next that the integration of machine learning algorithmss further improved model predictions, reducing the required simulation times by about 18 percent. It is concluded that for different applications it is important to select the correct turbulence model so as to balance accuracy and computational efficiency. The contribution of this research to refine CFD methodologies and to provide some initial insight in optimizing fluid dynamics simulations for real world engineering problems is provided
Comparative Study of Bioleaching Efficiency of Rare Earth Element from Different Carbonatite Ores in Mongolia
Get PDFThe increasing demand for rare earth elements necessitates the development of environmentally friendly and energy-efficient extraction methods. This study investigates the bioleaching efficiency of rare earth elements from carbonatite ores using both pure and mixed bacterial cultures under ambient conditions. Ores from the Lugiin Gol and Mushgia Khudag deposits underwent a 7-day bioleaching with a bacterial mixture and pure cultures origin from copper ore. The progress of bioleaching was monitored by measuring dissolved metal concentrations, pH, and oxidation-reduction potential. X-ray diffraction analysis revealed that rare earth elements predominantly exist as minerals synchysite and bastnasite in the Lugiin Gol ore, monazite and parasite in the Mushgia Khudag ore. Chemical analysis determined the total REE content to be 3.99% in Lugiin Gol ore and 7.66% in Mushgia Khudag ore. The bioleaching, conducted with a solid-to-liquid ratio of 1:6 at room temperature and utilizing six different ore particle sizes, demonstrated that mixed bacterial cultures were significantly more effective than pure cultures. The highest metal recovery rates achieved were 15.85% and 6.23% (wt.%) for Lugiin Gol and Mushgia Khudag ores, respectively. Furthermore, particle size was identified as a crucial factor influencing bioleaching efficiency, with optimal results observed at 4.0–5.0 mm particle sizes, likely due to the weakening of the rare earth element bearing ore matrix
The Impact of Global Financial Crisis on Capital Structure: Analyzing the Severity of Its Impact on Engineering SMEs in Pakistan?
Get PDFThe current study examines the impact of global financial crises on the capital structure of engineering small and medium enterprises in Pakistan. The study takes GDP as an indicator of financial crises and total debt to total asset ratio, long-term debt to total debt ratio and long-term debt to total asset ratio as indicators of capital structure. The study mainly focuses on panel data from 5 years by including pre and post-crisis periods. The sample size of the study is 20 engineering small and medium enterprises in Pakistan. The research uses inferential statistical techniques to extract results. The findings depict that the financial crises have an insignificant effect on the capital structure of engineering small and medium enterprises in Pakistan. Moreover, by analyzing the statistics, we see that debt financing is frequently decreasing in engineering small and medium enterprises in Pakistan after the occurrence of this financial crisis globally
Minimally Invasive Digital Denture Duplication with Extra – Oral Scanning and 3D Milling for Enhanced Patient Comfort in Dementia Care: A Technical Cased Report
Get PDFAim & Background: Traditional complete denture protocols typically involve several patient appointments and multiple laboratory procedures. However, various workflows integrating digital technology can streamline the process, enhancing speed and predictability. This technical case report represents a digital denture duplication process.
Case Description: The 67-year-old male patient diagnosed with mild dementia presented with well-formed edentulous ridges and a history of maxillary and mandibular complete dentures. Due to his medical condition, he required a backup set. A reliable and efficient method involving extra-oral scanning, printing trial dentures, a functional impression, and scanning of trial dentures followed by 3D milling was used to replicate the existing dentures with minimal discomfort. The patient expressed satisfaction regarding retention, stability, and aesthetics.
Conclusion: This case demonstrates the effectiveness of digital technology in meeting the needs of elderly and cognitively impaired patients, providing a practical solution for maintaining denture function and aesthetics.
Clinical significance—Digital technology provides the advantage of faster turnaround times for denture duplication, which is particularly beneficial in managing the needs of dementia patients who may require quick adjustments or replacements due to their condition
Comparison of the Thermohydraulic Efficiency of a Rectangular Fin Tube Heat Exchanger with or without Modified Rectangular Winglet Vortex Generator
Get PDFPerformance Evaluation Criteria (PEC)/ Thermo hydraulic efficiency of a Heat Exchanger may be increased using a Modified Rectangular Winglet Vortex Generator (MRWVG). This Modified rectangular Winglet Vortex Generator is fixed on a rectangular type fin plate and this plate is used to find the Performance Evaluation Criteria with the help of a wind tunnel. The wind tunnel test rig is used for calculating the experimental data with and without a rectangular winglet vortex generator. In this test section first, take a reading on the rectangular plate without the modified rectangular winglet Vortex Generator, and then after fixing the modified rectangular winglet and all experimental repeats same with the modified rectangular winglet Vortex Generator to find PEC. The maximum PEC is calculated experimentally for both with or without using the modified rectangular winglet and after that, a comparison should be done and find the maximum Performance Evaluation Criteria
A Hybrid Stability Index and Harris Hawks Optimization for the Optimal Reallocation of Generators in the Presence of SVC
Get PDFIncreasing system efficiency and dependability in a very competitive power market depends on best use of available resources. This work offers a hybrid approach for generator tuning and Static VAR Compensator (SVC) placement selection to enhance system performance. The perfect generator settings are found using the Harris Hawks optimization (HHO) method; a hybrid stability index (HSI) is then used to choose the best SVC location. Measuring voltage stability, the HSI combines the Vi/Vo index with the L-index. A multi-objective function is developed to lower losses, lower the cost of power generating, and improve voltage stability. The proposed method was tested on an IEEE 30-bus system under both normal operating settings and extreme system disturbances brought on by line outages. Under both normal and fault situations, the results show the effectiveness of the HHO-based approach in raising power system stability and operational performance when compared to those obtained using the Harmony Search (HS) technique
Optimal Machine Learning Models for T20 Cricket: The Role of Dangerous Balls in Match Outcomes
Get PDFThis study explores the application of machine learning models Logistic Regression, Multilayer Perceptron (MLP), and Decision Tree (CRT method) to predict the outcome of T20 International cricket matches based on dangerous deliveries consisting on two key independent variables: wickets lost and extras conceded. The dataset, comprising 2,492 matches, was analyzed to understand the impact of these variables on match results. By comparing the performance of these models across the first and second innings of matches, the study aims to identify which model best captures the dynamics of match outcomes. The models were evaluated in terms of their predictive accuracy, interpretability, and the significance of the variables, with a particular focus on the role of wickets in determining match results. Although all three models proved effective in predicting match outcomes, the Decision Tree model stood out as the most reliable and comprehensible, providing meaningful insights into the connection between match dynamics and results. The findings highlight the potential of machine learning techniques in sports analytics, offering valuable insights for both researchers and cricket analysts in forecasting match outcomes and understanding the factors that influence a team's success in T20 cricket
Detection of Cyberbullying on Social Media Using Machine Learning
Get PDFIn this work, there is an argue for a focus on the latter problem for practical reasons. This project show that it is a much more challenging task, as the analysis of the language in the typical datasets shows that hate speech lacks unique, discriminative features and therefore is found in the ‘long tail’ in a dataset that is difficult to discover. Later in this project there is an propose of Deep Neural Network structures serving as feature extractors that are particularly effective for capturing the semantics of hate speech. These methods are evaluated on the largest collection of hate speech datasets based on Twitter, and are shown to be able to outperform state of the art by up to 6 percentage points in macro-average F1, or 9 percentage points in the more challenging case of identifying hateful content
Generative AI for Artistic Creativity: Exploring the Intersection of Computer Science, Psychology, and Fine Arts
Get PDFThe purpose of this study is to understand how this powerful technology of generative AI, computer science psychology, and fine arts works in the context of creative work. This paper focuses on exploring the application of AI techniques in enhancing creativity in several fields such as architecture, arts, music, and design. Using four generative AI techniques, namely, VAE, GANs, RNNs, and Transformer models, it is possible to develop generating brand-new creative work, as this study proves. The performance of each algorithm was evaluated through experiments, yielding the following results: VAE had a creativity of 89%, GAN diagram depicted that image generation was 91% accurate, RNN had a success rate of 92% for music composition and finally transformer model marked 95% efficiency in architectural design. Thus, the idea that the establishment of AI as an artist depicts both the capability of AI systems to work with the human mind to amplifying its creativity, as well as creates considerations of originality with emphasis on who should be considered the author. According to this research, it is found that generative AI can significantly enhance creative industries as it opens new avenues for artists. However, the various canvases about its legal and ethical perspective are still being debated as AI draws progress
Evaluation Of Mechanical Properties In AA2219-B4C Composites Produced By Stir Casting And Age Hardening
Get PDFThe mechanical properties exposure to heat treatment is examined in this work for AA2219 strengthened by boron carbide (B4C) particles. The content of reinforcement B4C included 2 wt% and 4 wt%. Consistent reinforcing particle distribution was visible in the microstructure and improved strengthening phases. Vickers' hardness increased to 9.67% at 4wt% of B4C and for 2wt% of B4C the hardness was enhanced to 11.24% after the completion of the heat treatment. At a 2 wt% concentration of B4C, UTS grew by 15.16%, and at a 4wt% concentration, it increased by 6.80%. The improvisation has been found in the yield strength of 6.37% at B4C particles containing 4wt% and at 2wt% of B4C particles exhibited 10.32%. Additionally, there had been a drop in ductility of 25.09% and 14.29%, and this implies that strength and ductility compromise. The conclusion of composites' have the potential for high-performance application