Journals of Universiti Tun Hussein Onn Malaysia (UTHM)
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Influence of Parameters on Bead Geometry in Robotic GMAW Of Single-Sided Bevel T Joints with A36 Steel
Get PDFThis study analyses the impact of welding parameters on the quality of bevel-prepared T-joint welds. The experiments utilised a robotic welding system to ensure consistency and accuracy in the welding procedure. The welding parameters included voltage (20V-22V), current (105A and 110A), and weaving width (0.1mm - 0.3mm), while the travel speed was maintained at 2mm/s within predetermined ranges. The quality of the welds was assessed using Vickers Hardness Testing, which offers insights into the mechanical properties and microstructure of the weld zone. The findings indicate a correlation between the welding parameters and the hardness distribution across the weld bead, heat-affected zone (HAZ), and base metal. The findings indicate a significant relationship between the welding parameters and the hardness distribution throughout the weld bead, heat-affected zone (HAZ), and base metal. Variations in voltage and current have been found to impact the heat input, thereby influencing the cooling rate and, in turn, the microstructure and hardness of the weld. The travel speed significantly influenced weld bead geometry and penetration depth, subsequently affecting the overall quality of the weld. This study offers significant insights into enhancing robotic GMAW processes for T-joint welding with bevel preparation. The results can enhance weld quality and efficiency in automated welding applications across multiple industries
Effect of Tire Pressure Factor Toward Fuel Consumption of Passenger Vehicle
Get PDFTotal amount of car on street is increasing and it concern the scientist, politician and the public regarding the air pollution is caused. Air pollution due to motorized vehicle can be harmful to the environment and humans. The main objective of the project is to find out how the tire pressure effects the fuel consumption of passenger car. Perodua Myvi was used in this experiment to measure the fuel consumption at various tire pressure which are 170, 210, 250 kPa. This experiment conducted in UTHM Pagoh where the road stretch to 4.7 km but the desired distance is 51.7 km so, the driver has to drive 11 times around UTHM Pagoh road. This experiment conducted at least three times at different tire pressure and after each test drive the fuel consumption was recorded using On-Board Diagnostic II (OBD II) under dry weather
Application of Artificial Neural Networks to Identify Earthquake-Induced Structural Damage in Residential Buildings
Get PDFStructural damage in residential buildings can significantly compromise the safety of occupants, reduce the structural integrity of the building, and shorten its overall lifespan, potentially leading to costly repairs, decreased property value, and increased risk during natural disasters such as earthquakes or storms. Traditional methods for assessing structural damage primarily depend on manual inspections, which are not only time-consuming and labor-intensive but also susceptible to human error, subjectivity, and inconsistency. These limitations can lead to delayed detection of critical issues, inaccurate assessments, and increased risk of overlooking hidden or early-stage damage, ultimately compromising the effectiveness of maintenance and safety measures. By employing a comprehensive dataset that includes a range of structural characteristics and damage indicators, this study trains a neural network model to identify and learn patterns linked to structural damage. This study investigates earthquake-induced damage in different structural components of residential buildings, employing hundreds of feature sets including building height, number of floors, earthquake intensity, damping ratio, crack location, and material properties to train and validate a network for damage prediction. The performance of the ANN is evaluated, demonstrating superior accuracy and efficiency. The results highlight the potential of ANNs to revolutionize structural health monitoring by providing rapid, cost-effective, and reliable damage assessments, thereby enhancing preventative maintenance and mitigating risks associated with structural failures
Sustainable Biodiesel Production from Waste Cooking Oil Using Diatomite as a Catalyst
Get PDFBiodiesel production from waste cooking oil via the transesterification process is one of the sustainable alternatives to fossil fuels. This study explores single use of diatomite as an alternative catalyst for biodiesel production that can significantly benefit the green energy industry. The experiment manipulated the methanol-to-oil ratio and catalyst dosage required by transesterification of fresh and waste cooking oil to maximize biodiesel yield. The use of diatomite in the transesterification of waste cooking oil produced a biodiesel yield of 90.49%, which was closely comparable to the 93.28% yield obtained from fresh cooking oil. The optimal condition was achieved with a 6:1 molar ratio of methanol to oil and 1.0 wt% diatomite. FTIR analysis of biodiesel sample from fresh and waste cooking oil produce new peaks at 1435 cm⁻¹ attributed to methyl bending vibration that occurs in alkanes which reflects characteristic of the biodiesel composition. In addition, presence of methyl ester was confirmed at 1196 cm⁻¹ which verified succesful of transesterification process. Diatomite\u27s reusability was efficient, achieving up to 70% conversion after three cycles, showing its potential to reduce biodiesel production costs. This study demonstrated that diatomite was an effective catalyst for the transesterification process, contributing to the advancement of sustainable biodiesel energy
Education 2030 - Achievements of TVET in Asia and The Pacific along with The Fourth Industrial Revolution
Get PDFThe modernization of TVET has not occurred with a system-wide approach covering the entire spectrum of TVET institutes worldwide. The literature that incorporates the Sustainable Development Goal for Education (SDG4) and the fourth industrial revolution in TVET is very rare to be found from international and comparative standpoints since these areas are still emerging. Further, case-based or single country-based experiences do not provide sufficient information to make informed decisions. Therefore, more empirical studies are needed on the adoption of SDG4 in TVET institutes to gain a broad-based understanding of the prevailing context. Given these gaps in the scholarship, the present study investigated the status of the adoption of SDG4 in TVET institutes. Accordingly, the study collected data covering the areas of 1) the teaching and learning context, 2) steps taken to impart skills for employment, and 3) steps taken to enhance the capacities of staff in response to the changing world of work from fifteen Asian and Pacific countries. Four hundred and twenty-eight TVET staff responded to the survey. The findings showed significant differences by the regional classification of the country and by the type of TVET institute. The findings of the study are novel and provide ample evidence for the status of TVET in incorporating SDG4 in the fourth industrial revolution era. The findings also showed that the policymaking bodies must take active measures to increase responsiveness in fulfilling SDG4 and addressing challenges brought about by the fourth industrial revolution technologies
Investigation on Chips Morphology of Machining AISI 4340 under Cryogenic and Cryogenic MQL Conditions
Get PDFAISI 4340 is a medium carbon low alloy steel that is widely used in heavy industries due to its exceptional material properties such as high hardness and high wear resistance. However, these feature presents significant challenges to the manufacturer thus, necessitating further exploration to improve its machinability. To address this issue, this study aims to analyse the chip morphology, namely chip serration, chip saw-tooth distance, and chip thickness collected during end milling of AISI 4340 under two cutting conditions of cryogenic LN2 cooling and the combination of cryogenic LN2 and Minimum Quantity Lubrication (cryoMQL). By varying the cutting parameter of cutting speeds (Vc), feed rates (fz), axial depths of cut (ap), and radial depths of cut (ae) in these two conditions, the results indicate that the combination between cryogenic and MQL yield better results interm of less chip serration, decrease saw-tooth distance and thinner chips when compared to the standalone coolant technique of cryogenic LN2. The results can be contributed by both cooling and lubricating effect from LN2 and oil from MQL technique that effectively reduce the cutting temperature and limit the temperature built-up at the tooltip. These combinations reduce tool wear, lower friction, and decrease heat generation during cutting thus improving the machinability of AISI4340 especially in critical application
Evaluation and Selection of Tower Crane Stabilization Control Systems Using a Multi-Criteria Decision-Making Approach
Get PDFThis study applies the Choosing by Advantages (CBA) decision-making method to evaluate and select appropriate stabilization control systems (SCS) for retrofitting the KБ-235 tower crane. Recognizing the widespread use and inherent instability of legacy crane models under dynamic wind and load conditions, two SCS alternatives are compared: a Passive Stabilization Control System (PSCS) and an Active Stabilization Control System (ASCS). The evaluation incorporates both technical and operational factors, including responsiveness to load swing, wind resistance, installation complexity, maintenance, and system precision. Attributes of each alternative are assessed using expert-validated criteria, followed by the quantification of each system’s advantages (IoA). Cost versus IoA analysis reveals that although the ASCS demands higher investment, it delivers superior stability performance and safety outcomes, with an IoA approximately five times that of the PSCS. The method was validated using assumed values from industry literature and expert input. These findings support the integration of structured decision-making frameworks in construction engineering and provide practical insights for upgrading legacy lifting equipment in resource-constrained environments
Coastal Erosion Monitoring Along the Coast of Negeri Sembilan, Malaysia
Get PDFCoastal monitoring, mapping and analysis are comprehensive for various coastal studies, such as advancement of regression planning, geohazard identification, decomposition- enhancing research, and theoretical or predictive modelling or coastal characterization. The objectives of this research were to identify the overview of coastal erosion monitoring along the coast of Negeri Sembilan, Malaysia. The coastal erosion assessment approach includes the creation of sediment cells for the coastal area, as well as the collecting and examination of secondary data related to the research areas. Categorization of erosion has been concluded based on locations of study area. Category 1 erosion was discovered along the coastline at the PD Waterfront, Batu 1, Jalan Pantai Port Dickson, The Regency Tanjung Tuan Beach Resort (Batu 5), Tanjung Gemok, Kampung Gelam, and Pantai Teluk Kemang (Batu 8). Pantai Tanjung Gemok, a prominent recreational beach, is currently experiencing groyne erosion downdrift. Apart from that, a groyne is being eroded downdrift in Pantai Regency Batu 5, Negeri Sembilan
Dynamic Properties of Pot Bearing Via Modal Analysis
Get PDFBearings represent one of the most sensitive and demanding elements in load transfer, particularly in structural support systems, which have some of the highest requirements regarding reliability and performance in structural engineering. One widely used structural bearing is the mechanical pot bearing. This compact bearing is especially useful for transmitting large vertical loads while accommodating extensive movements and multi-directional rotation. Understanding the dynamic behavior of the pot bearing in terms of natural frequencies, mode shapes, and damping is a necessity for enhancing its design and failure limit. Since it is composed of several materials, the pot bearing exhibits complex material behavior, making the measurement of its dynamic properties challenging in real practice. Modal analysis is one of the best methods used to determine the dynamic properties of materials. Consequently, the main objective of this research is to determine the dynamic properties of the pot bearing, specifically natural frequencies, mode shapes, and damping, through numerical modeling and experimental work based on modal analysis. From the findings, the relative errors between the finite element and experimental modal analyses for the first mode are quantified at 15.29%, whereas for the second mode, the corresponding value is 10.13%. The third mode demonstrates a relative error of 9.67%, while the fourth mode exhibits the lowest relative error of 8.81%. A strong agreement in mode shape was observed between the finite element model and experimental modal analysis results. In conclusion, modal analysis proved to be an effective technique for capturing the dynamic characteristics of pot bearings. The validated numerical model offers a reliable basis for further analysis, optimization, and integration into broader structural dynamic assessments
Study of the Durability Against Acid Sulfuric Attack and Accelerated Carbonation of Eco-Efficient Self-Compacting Concrete Blended with Marble Powder
Get PDFReinforced concrete structures can suffer from numerous problems such as the aggressivity of the environment and the carbonation phenomena. The introduction of fine industrial by-products (FIB) can reduce the permeability and hence improve the concrete durability. Marble industry generates high quantity of fine residue (marble powder) that can be used as FIB to produce an eco-cement. In this concern, five self-compacting concrete (SCC) mixtures were prepared using a constant water to binder ratio of 0.40, one as reference mix and four containing marble powder as a partial replacement of ordinary Portland cement (OPC). The durability of SCC subjected to sulfuric acid attack and accelerated carbonation were assessed. X-Ray diffraction analysis (XRD) were carried out to identify the mineralogical composition before and after durability tests. The results have shown that the use of marble powder is beneficial to improve the resistance of SCC to acid sulfuric attack. However, the incorporation of marble powder seems to accelerate the carbonation of SCC specimens.