Journals of Universiti Tun Hussein Onn Malaysia (UTHM)
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Study on the Performance and Hydration Mechanism of Hybrid Activation of Vanadium-Titanium Iron Ore Tailings
Full text linkThis paper investigates the activation of vanadium titanium iron ore tailings (VTIOT) to enhance their cementitious potential. Building upon previous studies, it explores two hybrid activation methods, thermal and chemical activation, to analyze how calcination temperature affects the physical and chemical properties of VTIOT and the performance of resulting cementitious materials, and how different activators affect the performance of VTIOT cementitious materials, and to analyze the mechanism of hydration. Through various analyses including TG-XRD, SEM, alkali leaching, mechanical testing, hydration heat analysis, and TGA, the hydration mechanism of VTIOT cementitious materials is examined. Results indicate minimal changes in micro-morphology and mineral phase of VTIOT calcined within a range of 550℃ to 950℃ for 2 hours. Moreover, mortars doped with 30% of VTIOT from different calcination temperatures exhibit comparable compressive strength and activity index to uncalcined VTIOT. Notably, a 0.2‰ dosage of Diethanolisopropanolamine (DEIPA) yields an 85% activity index, outperforming other dosages and activators. Additionally, DEIPA prolongs the induction period of hydration heat and increases the exothermic peak and hydration exotherm amount within 7 days compared to other activators. These findings shed light on the efficacy of hybrid activation methods and the influence of activators on the hydration kinetics of VTIOT cementitious materials
A Sustainable Practices of Utilizing Ceramic Tile Waste to Replace Coarse Aggregate in Normal Concrete
Full text linkDue to poor construction waste manegement and disposal problem, construction waste is an emerging issue in the Malaysian Construction Industry (MCI). Massive construction projects affect the environment and produce huge amount of construction waste, including ceramic tile waste. The research aim is to figure out the mechanical characteristics of normal concrete under compressive strength and four-point bending tests with different percentages of ceramic tile waste replacement. Ceramic tile waste is recycled to replace coarse aggregate in developing a designed strength of 30 N/mm2 at 28 days. 10% of the cement is substituted with fly ash. Maximum particle for fine and coarse aggregates are 5 mm and 10 mm in sizes. A uniform ratio of 0.545 water-to-cement (w/c) and a concrete mix ratio of 1:2.61:2.71 (Cement: Fine aggregate: Coarse aggregate) are applied in the Department of Environment (DOE) technique. Thirty-six-cylinder specimens (150 mm X 300 mm) and eighteen prism specimens (400 mm x 100 mm x 100 mm) are casted, cured and tested to examine their properties. 20% crushed gravel is replaced with ceramic tile waste to obtain higher compressive and flexural strengths, measured 39.21 N/mm2 and 3.51 N/mm2 respectively. By turning waste into wealth, this research can reduce the dependency on natural raw materials, recycling recyclable resources, reduce the disposal of ceramic tile waste and minimize negative impacts on the environment
LSTM: Anomaly Activity Type Classification Using Distributed Acoustic Sensing Based on MFCC Features
Full text linkThe intergrity and connectivity of the fiber optical network are important in preserving the quality of services and internet realibility between providers and end users. However, these network are vulnerable to disruptions due to unitentional break and damage caused by physical disturbances such as construction activity. An accurate classification of anomaly activty at surounding area plays a crucial role in monitoring the buried fiber optical network from harm which can lead to denial of services. Distributed acoustic sensing (DAS) with combination of deep learning-based technique have potential in targeting this issue, by leveraging the unique pattern of vibration signal measured by the DAS to classify and identify anomaly activities. This work demonstrated utilization of dark fiber buried along the road until the server room, then connected to the DAS interrogator unit(IU). The vibration signals induced by construction hand tools, including hoe, shovel, and sledgehammer, which are used to mimic anamoly activity, are measured by DAS IU and underwent pre processing before exract the mel frequency cepstral coefficient (MFCC) features for long short- term memory (LSTM) model training. The average accuracy score using 25 MFCC resulted up to 87% indicating that the proposed method hasa great potential for anamoly activity monitoring for fiber break prevention
Detection of Oil in Water Using Photodiode and Internet of Things
Full text linkOil spills in irrigation ditches can have severe environmental and agricultural consequences. We proposes a system that can detect oil spill using a photodiode and an Internet of Things (IoT) platform to enable real-time monitoring. The system integrates a blue light-emitting diode (LED), a photodiode, and an ESP32 microcontroller, which measures resistance changes as an indicator of oil presence in water. Experimental evaluations were conducted by varying the distance between the light source and sensor (6 cm to 9 cm), oil volume (50 mL to 200 mL), and exposure time (1-6 hours). Results indicate that resistance values for oil-free water range from 300 kΩ to 500 kΩ, while oil-contaminated water consistently exhibits resistance below 18 kΩ. The optimal distance for accurate oil detection was determined to be 8 cm, maintaining stable resistance values. Increasing oil volume and prolonged exposure time reduced light penetration, causing a decrease in resistance. Real-time monitoring via the Blynk application provides immediate alerts when oil is detected. The proposed system offers a low-cost, efficient, and scalable solution for early oil spill detection in agricultural irrigation systems, minimizing environmental damage and improving water quality management
Smart Flow Computer: Leveraging IoT for Accurate and Efficient Gas Flow Measurement in The Oil and Gas Industry
Full text linkAccurate measurement of gas flow is crucial in the oil and gas sector, typically accomplished using orifice sensors and based on AGA report 3 standards. This research obtains a flow computer configuration to meet the increasing need for accurate and efficient remote meter reading, integrating IoT technology for real-time monitoring, and utilizes complicated calculations based on AGA report 3 namely Smart Flow Computer. The study implements and assesses the Smart Flow Computer, which uses an ESP32 microcontroller and a current-to-voltage converter, against the Kelton Flocalc software. The verification of pressure, differential pressure, and temperature outputs revealed relative deviation ranging from 0% to 0.23%. These inaccuracies are attributed to signal impurity, measurement uncertainty, and equipment resolution. The ESP32\u27s 12-bit ADC, which has 4096 levels, has a deviation less than 1%. This contrasts with the 14-bit ADC, with 16,384 levels, found in conventional flow computers. This research shows that the ESP32-based Smart Flow Computer has high accuracy with minimal deviation, meeting the standards set by the metrology directorate, indicating its potential to revolutionize remote gas flow monitoring in the oil and gas industry. By integrating IoT technology and advanced microcontrollers, this innovative solution offers real-time data acquisition and reliable calculations, significantly improving operational efficiency and precision
Flight Performance of a VTOL Version of a Transport Blended Wing-Body UAV
Full text linkThe blended wing-body (BWB) UAV with vertical take-off and landing (VTOL) capabilities has garnered attention in aviation due to its advancements and advantages, such as noise reduction and safety features. This study analyses BWB UAV VTOL flight performance and mission capabilities. The evaluation involves conceptual design, theoretical calculations, and data analysis to assess parameters such as range, endurance, weight, manoeuvrability, and more. Furthermore, mission profile analysis is used for surveillance scenarios and offers insights into the UAV\u27s performance in these operational environments. Microsoft Excel is the main tool used in this research for calculations, simulations, and data analysis. Using a spreadsheet, this method computes critical performance metrics according to the mission requirements, operational parameters, and design specifications of the UAV. The study\u27s findings provide important insight into the BWB UAV VTOL prototype\u27s flight characteristics and mission capabilities. These results point to the aircraft’s ideal operating conditions and assist in identifying any potential drawbacks or performance limitations that may vary as further study proceeds. Microsoft Excel provides a useful and approachable way to evaluate UAV VTOL performance. It enables fast updates and modifications to meet changing mission requirements and design iterations. Other than that, a thorough examination of the flight characteristics and mission profile of the BWB UAV VTOL prototype brings this study to a close. It offers insightful information that can be used to improve design, schedule operations, and predict performance in the field of aerial transportation and other pertinent applications
Conceptual Design and Analysis of a Shrouded-Type Wind Turbine for Low Wind Speed Condition
Full text linkWind energy represents a valuable renewable resource with significant potential for electrical power generation. While conventional wind turbines have been well-developed for electricity generation, they suffer from reduced efficiency and limited power output in remote areas with low wind speeds (typically below 7 m/s), where wind energy extraction becomes economically unviable. The central research question addressed in this study is: Can shrouded wind turbine technology significantly improve power generation efficiency compared to conventional open rotor designs under low wind speed conditions? This study aimed to propose a conceptual design of a shrouded wind turbine and analyze its performance under low wind speed conditions ranging from 4 to 7 m/s. The proposed wind turbine\u27s performance was analyzed through extensive computational fluid dynamics (CFD) simulations using ANSYS Fluent. Key performance parameters, including power coefficient (Cp), tip speed ratio (TSR), velocity distribution, pressure characteristics, torque generation, and power output capabilities, were investigated. Results demonstrated that the shrouded wind turbine achieved higher Cp values at elevated tip speed ratios compared to conventional open rotor configurations. Specifically, the shrouded design generated 17.1% more power at 4 m/s and 5.0% more power at 7 m/s wind speeds. The shrouded configuration increased air velocity by 11.6% at 4 m/s and 7.5% at 7 m/s compared to the open rotor design, demonstrating enhanced wind energy capture efficiency in low wind speed environments
Proposed Design of Wind Turbine for Highway Energy Harvesting
Full text linkThis study explores the feasibility of deploying wind turbines alongside highways to harvest untapped wind energy generated by vehicular traffic, with a focus on Malaysia\u27s North-South Highway. The research aims to analyze local wind meteorology data, identify suitable wind turbine designs for roadside applications, and propose mechanically optimized configurations to enhance energy harvesting efficiency and safety. The methodology involves a comprehensive literature review on wind patterns, structural considerations, and turbine types from international contexts, followed by the simplification and design of vertical axis wind turbines (VAWTs), specifically Darrieus and Savonius models, using SolidWorks software. Computational fluid dynamics (CFD) simulations were conducted at a wind speed of 30.56 m/s (equivalent to Malaysia\u27s highway speed limit of 110 km/h), evaluating parameters such as blade count, materials (e.g., high-grade steel alloys), airflow density, pressure, velocity, and power output. Data from the Malaysian Meteorological Department (2019–2022) informed site-specific assessments, particularly for the Pagoh to Yong Peng section. Findings indicate that VAWTs are most appropriate for highway installations due to their adaptability to turbulent, low-speed winds. The Darrieus turbine outperformed the Savonius and a previous design, achieving an average velocity of 27.460 m/s, a pressure of 101797.48 Pa, and a power output of 3.163 kW, exceeding the Betz limit of 1.875 kW and demonstrating superior energy capture efficiency. This research contributes to renewable energy integration in transportation infrastructure by providing evidence-based recommendations for VAWT deployment, highlighting mechanical optimizations for safety and performance. It informs policymakers, engineers, and developers on sustainable practices, potentially reducing reliance on fossil fuels while enhancing highway energy self-sufficiency
Isu dan Cabaran Kepimpinan dalam Mentadbir Urus Institusi PLTV: Leadership Issues and Challenges in Administering TVET Institutions
Full text linkMalay:
Kajian ini bertujuan untuk mengenal pasti isu dan cabaran kepimpinan dalam mentadbir urus institusi Pendidikan dan Latihan Teknikal dan Vokasional (PLTV) di Malaysia. Melalui pendekatan Systematic Literature Review (SLR), sebanyak 36 artikel berkaitan telah dikenalpasti, di mana 34 artikel telah disaring dan 20 artikel terpilih untuk analisis lanjut. Dapatan menunjukkan bahawa struktur kepimpinan dan pengurusan dalam institusi PLTV sering kali dianggap lemah dan tidak berkesan, dengan cabaran utama termasuk kekurangan pengetahuan dan kemahiran kepimpinan, komunikasi yang lemah, serta beban kerja yang tinggi. Penelitian ini menekankan perlunya langkah perubahan yang strategik untuk meningkatkan keberkesanan kepimpinan dalam institusi PLTV, agar dapat menyokong perkembangan sistem pendidikan teknikal dan vokasional yang lebih baik. Hasil kajian ini diharapkan dapat memberikan panduan untuk penambahbaikan dalam pengurusan dan kepimpinan institusi PLTV di masa hadapan.
English:
This study aims to identify leadership issues and challenges in the governance of Technical and Vocational Education and Training (TVET) institutions in Malaysia. Through a Systematic Literature Review (SLR) approach, a total of 36 relevant articles were identified, of which 34 articles were screened and 20 articles were selected for further analysis. Findings indicate that the leadership and management structures in TVET institutions are often considered weak and ineffective, with key challenges including lack of knowledge and leadership skills, poor communication, and high workload. This study emphasizes the need for strategic change measures to improve the effectiveness of leadership in TVET institutions, in order to support the development of a better technical and vocational education system. The results of this study are expected to provide guidance for improvements in the management and leadership of TVET institutions in the future
Engineering Properties and Production Costs of Paving Blocks Incorporating Different Types of Agricultural Wastes
Full text linkOpen-field burning is still widely utilized as a traditional waste disposal method in agriculture, particularly in developing countries. In some locations in Yogyakarta, Indonesia, the ashes formed by the open field burning of agricultural waste have not been utilized to their full potential. This research aims to utilize waste ashes from three different agricultural industries, including rice husk ash (RHA), sugarcane bagasse ash (SBA), and corn cob ash (CCA), as cement replacements in the manufacture of paving blocks. The purpose of utilizing agricultural waste ashes was to reduce soil pollution caused by waste in plantation areas around Yogyakarta, as well as initiatives to reduce the use of cement for non-structural constructions. The laboratory scale experiments examined the engineering properties of paving blocks, including slump flow, compressive strength, splitting tensile strength, flexural strength, mass density, mass loss, water absorption, porosity, and initial suction rate (IRS). The fresh properties experiment was done during the mixing process when the mortar was in the fresh state, the mechanical properties experiment was done during the curing period of 7, 14, and 28 days, while the physical properties experiment was only done on specimens after 28 days Besides, an analysis of the production cost was also conducted. This research found that the maximum amount of waste that can be used is 20% of the total binder for a composition ratio of 1:9 (binder: sand). The utilization of more than 20% of waste causes a significant decrease in fresh properties, prohibiting its rapid production and delaying the hardening process. Based on the mechanical properties, it was found that a 10% composition of agricultural waste ashes is the optimum amount recommended for use with comparable properties to normal paving blocks. In addition, by utilizing 10% of waste ashes in total binder, it is possible to reduce production costs by 2.25% to 2.43%