A Semi-System Approach to Determine the EHL Model over the Contact Length and Its Effect in Helical Gear Pair
Ashutosh Kumar*, Kiran More
DOI: 10.1654/zkdx.2024.29.2-15
Pages: 152-168
Abstract
Helical gears because of their low noise operation and better efficiency are one of the best choices for various industries wherever they are using parallel shaft gear drive. These gears normally operate in elastohydrodynamic lubrication (EHL) condition to transfer high torque. In such scenario the lube film thickness plays a very critical role in the fatigue life of the gears. It is important to know the contact pressure, lube film thickness and pattern of oil film pressure at critical points of load transmission. This research work is all about determination of lube film thickness, contact pressure and oil film pressure at all concern contact points on contact line.
To start with the research after analysing the past work done the critical points are being calculated as per AGMA 925 followed by detailed analysis on these points to establish their validity and significance. Critical Points are discussed.
Reynolds equation is used to establish the methodology of calculating the lube film thickness with numerical methodology concept for elastic deformation. A noble method of calculating the lube film thickness by following the methodology as discussed in Python is used here. The contact stress model generated in the Python is reviewed for sample example with analytical result to find its accuracy. Lube film thickness is calculated in line with AGMA 925 via Kissoft and each point pressure with lube film pattern is calculated by the Python tool in this research work. Finally, the developed software is also reviewed with historic example data and was found satisfactory.
Keywords
EHL, Contact line, KISSOFT, Python
Structural Analysis of New Octagonal Pre-Stressed Concrete for
On Shore Wind Turbine Tower Using Computational Fluid Dynamics (CFD)
Abdelrahman Eissa*, Arafa El-Helloty, A. Ehab
DOI: 10.1654/zkdx.2024.29.2-14
Pages: 139-151
Abstract
To produce electricity, the wind turbine’s tower needs to be sturdy enough to withstand the forces generated by the generator located at the tower tip. The tower height must be sufficiently elevated to capture more robust winds at more intense velocities. In addition to its ability to withstand wind and challenging weather conditions, it must also be cost-effective. Consequently, these results mention the cost overrun of the turbine. Therefore, this article presents the new version of the octagonal cross-section wind turbine tower, which effectively tackles weaknesses of previous studies in concrete wind turbine tower design and tackles obstacles concerning construction intricacy, transportation and installation, fluctuating wind loading, stress concentration, and material usage. In this study, dead, wind, fatigue, buckling, and seismic loads are considered for a tower with a 100-meter height and a 3.6 MW generator. The wind tower’s stress, deformation, buckling, and fatigue limits will be analyzed to verify compliance with design codes. Finally, the result mentioned that the newly proposed across-section was very effective. The ratio of about 50% and 30% decreasing ratio in the deformation and stress respectively smaller than the allowable stress.
Keywords
Concrete Structures, Horizontal Axis Wind Generators, Ansys, Finite Element Analysis
A Review Article on Relation between Mathematical Modelling and Machine Learning
Beena Bundela*, Seema Sharma, Bhawna Ruchi Singh
DOI: 10.1654/zkdx.2024.29.2-12
Pages: 123-129
Abstract
A mathematical model is an abstract description of a concrete system using mathematical concepts and language. The process of developing a mathematical model is termed mathematical modelling. Mathematical models are used in applied mathematics and in the natural sciences such as physics, biology, earth science, chemistry and engineering disciplines like computer science, electrical engineering as well as in non-physical systems such as the social sciences. It can be also taught as a subject in its own right. The use of mathematical models to solve problems in business or military operations is a large part of the field of operations research. ML is one of today’s most rapidly growing technical fields, lying at the intersection of computer science and statistics, and at the core of artificial intelligence and data science. Recent progress in ML has been driven both by the development of new learning algorithms and theory and by the on-going explosion in the availability of online data and low-cost computation. It is a collection of a variety of algorithms like neural networks, case-based reasoning, genetic programming, decision trees, random forests, self-organizing maps, support vector machines, etc. Because of the ML-based approaches’ modelling capabilities, science and engineering have made substantial use of them.. In this paper the main key is importance of ML in mathematical modelling in health issues like Diagnosis recognition of disease, Covid-19 etc. Further we present the scope of mathematical modelling with ML in many different areas which is helpful for researchers.
Keywords
Mathematical models, Machine Learning, Deep Learning
Trend and Development of School Science Education in India and China: A Comparative Study
Ajoy Ghosh, Surapati Pramanik*
DOI: 10.1654/zkdx.2024.29.2-10
Pages: 106-115
Abstract
Over the past few decades, the Asia-Pacific region especially the two most populated developing countries in the world, viz. China and India have made remarkable revolutions and developments in the School Science Education (SSE). The data available from international comparative studies like TIMSS and PISA revealed that Chinese-Taipei, Hong Kong (China), Shanghai (China), etc. provinces of China have outperformed in science competitions. This is a qualitative study, here the data are collected from various authentic sources and are analysed comparatively. In this study, the researcher will discuss how different educational policy reforms prioritized science education over the past few decades. This study also analyses the results from a few PISA science reports pointing out the major strengths and shortfalls of science education in areas like curriculum, pedagogy, examination system, and science teacher preparation in both countries that may be helpful for national educational policymakers, stakeholders or science education researchers to drive the School Science Education in a steady developed way under the 21stcentury learning. The authors sum up the article by pointing out the noteworthy policy reforms and changes. This comparative study is a valuable lesson for both the Chinese and Indian education systems as well as for the rest of the developing countries in the world.
Keywords
School Science Education (SSE), TIMSS, PISA, Policy reforms regarding SSE
Improved Electronic Band (Lattice Constants)
Uko Ofe*
DOI: 10.1654/zkdx.2024.29.2-9
Pages: 102-105
Abstract
Some structural and electronic properties of NaH in Rock-salt structure with space group, Fmm, in cubic (FCC) system, have been evaluated. The calculated quantities include: electronic band structure, lattice constant and density of state-using the exchange correlation potentials (GGA and GGA +U). The effects of these exchange correlation potentials on the quantities mentioned have been discussed. The results obtained are reasonable, and in agreement with other calculated methods, but no experimental data on electronic band structure of this compound have been recorded in literature.
Keywords
Exchange-Correlation functional, Band structure, GGA, GGA + U, WIEN2k code
Comparison of Curriculum of School Science Education of India and Singapore: A Comparative Study
Anisha Nandy, Surapati Pramanik*
DOI: 10.1654/zkdx.2024.29.2-8
Pages: 94-101
Abstract
The purpose of this study is to discuss and compare the curriculum for school science education between India and Singapore. Researchers followed qualitative data analysis methodology along with a comparative investigation strategy. The fundamental difference is India’s curriculum has emphasized rote learning over creativity, whereas Singapore cultivates creativity among its pupils. Through NEP 2020, Govt. of India has stepped forward to make up this unavoidable gap. This study compares the school education system, analyzes the science curriculum, and compares the curriculum of school science education between India and Singapore. No comparative study in this regard has been found in the literature which reflects the originality of the study.
Keywords
Science education, School science education, Science curriculum, Comparative study, NEP-2020
The Degree of Mathematics Teachers’ Application of Productive Thinking Skills in Jordan
Mohammad Ali Ghunaimat*, Ali Mohammad Alzoubi
DOI: 10.1654/zkdx.2024.29.2-7
Pages: 83-93
Abstract
The purpose of the study was to find out how often Jordanian math teachers used constructive thinking techniques. A questionnaire created by the researchers was one of the study’s instruments. The study used a descriptive research methodology 2. There were 452 math instructors in the First Directorate of Education in the Zarqa Governorate; 257 of them were female and 195 were male. These teachers made up the study population. 1. Using a stratified random technique, 117 males and 132 females made up the study sample. The study’s findings demonstrated a high degree of application and the greatest level of proficiency in the following areas: First: Urging students to self-regulate and monitor their level of knowledge in mathematics, Second: Asking students to interpret and express the mathematical problem in their own language. The study also showed that there were no statistical differences resulting from the variables of academic qualification and gender of mathematics teachers. The study recommended: Urging mathematics teachers to apply mathematical inference and mathematical justification skills, and activating postgraduate education programs.
Keywords
Creative thinking, Critical thinking, Mathematics teachers, Productive thinking
Factors Contributing to Poor Literacy among Grade 4 Learners in Gauteng Province of South Africa
Sizwe Marcus Mahlangu*, Thokozani Isaac Mtshali
DOI: 10.1654/zkdx.2024.29.2-6
Pages: 77-82
Abstract
Much research exists about South African learners’ literacy and numeracy challenges as well as their overall declining performance in schools. There are far fewer detailed explanations about the instructional practices and what teachers are actually doing in their classrooms to circumvent this situation. In depth research that attempts to understand literacy and numeracy challenges in Gauteng schools is eminent. Thus, the purpose of this study is to investigate the factors contributing to poor literacy among grade 4 learners in Gauteng Province. Data was collected through semi structured interviews and classroom observation from ten schools and in each school; we sampled three grade four classrooms and four learners from each class. The findings suggest that poor literacy is caused by multiple factors ranging from learners’ ability to lack of reading resources and reduced motivation and commitment to learn spelling, punctuations and comprehension. We conclude that poor literacy exists among grade 4 learners as results of learners’ inability teachers’ lack of skills and inadequate resources.
Keywords
Contextual factors, Reading Literacy, Learner achievement, Parental involvement, Resources availability
Behavior of Steel Plate Shear Wall Subjected To Lateral Loads
Alaa Abdelsalam*, Arafa El-Helloty, Ayman Sammra
DOI: 10.1654/zkdx.2024.29.2-5
Pages: 53-76
Abstract
In recent years, the need for lateral loads upgrades in building structures has increased due to the growing importance of steel plate shear walls (SPSW) for earthquake and wind resistant design. SPSW systems offer advantages such as robust post-buckling strength, substantial ductility, stable hysteretic characteristics, and high initial stiffness compared to conventional lateral load resisting systems. They allow for less structural wall thickness and lesser building weight compared to concrete shear walls, reducing construction time, and allowing for fast erecting without a curing period. Structures can be subjected to dynamic loads such as wind, waves, traffic, earthquake, and blasts, which can cause critical stresses in buildings, leading to excessive lateral sway and undesirable stresses and vibrations. Design and structural evaluation of building systems subjected to lateral loads are crucial. The present generation faces the challenge of providing adequate strength and stability of buildings against lateral loads. Different lateral load resisting systems are used in high-rise buildings due to the concern of earthquake-induced lateral loads. Steel plate shear walls (SPSW) have been extensively used as lateral load resisting systems in the past few decades. They consist of steel infill plates surrounded by boundary beams and columns and can be constructed in two types: unstiffened and stiffened infill steel plates. A cantilevered vertical plate girder is idealized as a SPSW system, with the steel infill plates acting as the web, boundary columns as flanges, and boundary beams as transverse stiffeners. SPSW systems have been researched since the early 1970s, with the most common research and application in North America being the unstiffened, thin SPSW system, while stiffened SPSW systems are more common in European area. Regardless of the system used, the determination of whether a SPSW system is the right application in general is important.
Keywords
Steel plate shear wall, Dynamic Analysis, Seismic load, Wind load, Modal Analysis, Stiffened steel plate shear wall, Unstiffened steel plate shear wall, Frequency
Phishing Detection Using Hybrid Machine learning Techniques
Rasha Gaffer M. Helali*
DOI: 10.1654/zkdx.2024.29.2-4
Pages: 45-52
Abstract
Cyber security has become a crucial component of the new digital age with more than 820 million users of internet in year 2023 and social media users are expected to reach 82.3% from the total number of internet users by 2024. According to these figures, security systems are required to shield the public from phishing scams, which have a negative impact not only on financial resources but also on people’s mental health by making them fearful to use the internet or surf. This drives efforts to find effective solutions for the issue. The swift alterations in phishing attack patterns necessitate constant improvement of existing phishing detection systems in order to effectively counter new and upcoming phishing attempts.
This research aims to identify common characteristics displayed by phishing websites and create a model to identify them. The dataset was used to train a number of models, including the Random Forest Classifier, Artificial Neural Networks, and Principal component Analysis. Feature selection and clustering technique were also integrated to detect unknown attacks. The dataset was collected from Kaggle and contains information of 549,346 entries. RF attained the highest accuracy of 94%.
Keywords
Cyber security, Phishing attacks, Machine learning, Neural Network, PCA
Trade Expansion, Governance and Environmental Degradation: New Evidence from Africa and Asia
Azuka Elvis Ozegbe, Stanley Emife Nwani*, Sunday Enebeli-Uzor
DOI: 10.1654/zkdx.2024.29.2-2
Pages: 15-27
Abstract
The purpose of this study is to examine how trade expansion and governance influence the quality of our environment in selected countries in Sub-Saharan Africa and Asia where environmental poverty appears to be alarmingly high. As globalization propelled by technology and digitalization disrupt trade barriers across nations, regions, and continents, some of its consequences are the race to the bottom and pollution haven. We used panel data for 26 African and Asian countries based on Grossman and Krueger’s model to regress carbon emission on trade, governance, foreign direct investment, and gross domestic product for the period 1996 to 2021 due to consistent data availability. We employed the panel autoregressive distributed lag modeling estimator to obtain the following results. First, both regions, we established that the influence of trade on environmental quality is significantly mediated by the quality of governance. Emphatically, the interactive effects of governance indicator and trade are negative and statistically significant in the long run for Africa. This result is worrisome as it justifies that Africa remains a pollution haven and her governance quality is weak. Second, in the short run, while environmental quality is adversely impacted by trading activities, governance quality appears to not matter in its interactions with trade on environmental quality. So, we concluded that the interactive role of governance in trade-environment nexus is a long run concerns as against a short run consideration.
Keywords
Trade, Governance, Environmental Degradation, Asia, Africa
Significance of Erotic Arts of Carving and Tourism in Hindu Temples in Kathmandu Valley
Bishnu Prasad Dahal*
DOI: 10.1654/zkdx.2024.29.2-1
Pages: 1-14
Abstract
Cultural tourism plays a key role in economic development and the study of heritage that signify different meanings for the host society and guest tourists. For host society, the erotic arts of struts (Tudal) is one which manifestly indicate the interrelationship between sex, nudity, arts of sex with fertility that are acts as the mechanism to maintain the socio-cultural order or equilibrium through the offerings of various cultural events and celebrations both manifestly or sometimes latently. But for the guest (tourist), these may be different than the host and these arts and architectures were the means to study the overall society and culture in very short time frame not only for the entertainment but also for the knowledge. So, cultural heritage and rituals are the window through which guest can understand the host society.
The aim of this article is to explore the significance of these cultures, arts and architectures of host society to maintain the mode of production, fertility and it is the means to socialize sex and religion together in Hindu orthodox system where sex as sinful activities in one hand and “sex is essential and basic human need which is related with the fertility and sexuality; that determines the production” to all. In other hand, this way of contradiction is very important in subject matter for the guest, researcher and anthropologist to dig out the depth of the knowledge, facts and figure that associated with the dialectic acts in the Hindu cultural system. This model of sharing system of knowledge and ideas that emphasizes the power relationship between the guests and host society across socio-religious, politico-economic, psychological, ecological and many more domains. So, apart from these, such arts of carving play vital role to promote tourism industry, knowledge sharing between guests and host.
Keywords
Erotic arts of carving, Sexuality, Fertility, Religion, Struts (Tudal), Tourism Efficacy, Work Pressure