Journals of Universiti Tun Hussein Onn Malaysia (UTHM)
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Inverse-Dash Rectangular Slot 2x4 Array 5.8 GHz Antenna for Multiple Access Integration of IoT Systems and Terrestrial Satellite Communication Networks
Full text linkLEO satellites provide a phenomenal solution for the provision of internet networks around the world, especially in remote areas. Along with this, the increasing demand for fast and stable information and communication network access technology, especially in applications such as the Internet of Things (IoT) and satellite communications, demands innovative solutions to overcome infrastructure limitations in remote areas. From 2022 to 2026, this need is expected to increase by around 25%. IoT technology, which is key in the industrial revolution 4.0 and the development of smart cities, relies heavily on the support of communication networks, especially in remote areas that are underserved by mobile and fiber optic infrastructure. This study proposes an optimal antenna design for point-to-point applications on WLAN-IoT networks integrated with LEO satellite communication systems. The antenna design uses a rectangular inverted-dash patch-shaped array configuration with an operating frequency of 5.8 GHz, designed to improve communication range and efficiency. The antenna has a high gain of 5 dBi and a directional radiation pattern that is suitable for difficult environments in remote areas. The prototype antenna test showed positive results with a return loss of -15.78 dB, a VSWR of 1.39, and a radiation efficiency of 96%. The test results also showed a significant increase in transmission signal strength compared to the reference antenna, providing an innovative solution to extend the range of the satellite communication system with high efficiency. This study emphasizes the importance of antenna design that takes into account technical specifications and environmental conditions to optimize the performance of communication networks in remote areas
3D Concrete Printing with Industrial Waste: Effects of GGBS and Spent Catalyst on Fresh and Hardened Properties
Full text link3D concrete printing (3DCP) is a revolutionary technology in construction that deposits concrete layers in a controlled way, reducing formwork, labour, and material waste. However, its heavy reliance on Portland cement and natural sand raises sustainability and performance challenges. This study determines the incorporation of Ground Granulated Blast Furnace Slag (GGBS) and spent catalyst (SC)—two industrial by-products—as partial replacements for cement (20–40% of GGBS) and sand (10–20% of SC) in 3DCP mixtures. The objective is to assess how these substitutions affect fresh properties (flowability, extrudability, buildability) and hardened performance (compressive and flexural strength at 7 and 28 days). Sixteen mix designs were cast with a water-to-cement ratio of 0.5 and 0.5% superplasticiser. Fresh-state tests included flow table measurements, manual extrusion through a 15 mm × 40 mm nozzle, and five-layer stacking trials. 100 × 100 × 100 mm cubes and 100 × 100 × 400 mm prisms were used to assess the hardened properties. Results indicate that GGBS enhances flowability and long-term strength, while SC accelerates early strength gain; all mixes exhibited acceptable printability. The optimum mix—30% GGBS and 20% SC—achieved the highest 28-day compressive strength (50.61 MPa) and flexural strength (6.73 MPa). These findings demonstrate that GGBS and SC are viable sustainable alternatives in 3DCP, improving environmental impact and structural performance without compromising printability
Metal Film-Based Flexible Sensor for Omnidirectional Airflow Measurement
Full text linkThe previous study on airflow sensors were fabricated using a flap device printed using polylactic acid (PLA) plastic, which had high stiffness, preventing the sensor from bending and returning to its original shape. The used aluminium (Al) strips exhibited relatively higher resistance values compared to copper (Cu), resulting in inconsistent resistance readings at various angles of bending measurement. This paper presents a new development of an enhanced metal film-based flexible sensor for application on omnidirectional 360-degree airflow measurement. The sensor was fabricated using copper film and velostat, a material made of polymeric foil (polyolefins) infused with carbon black to make it electrically conductive. The flapping device was modelled in SolidWorks (3D CAD) and printed using TPE 83A (Thermoplastic Elastomer) filament on a 3D printing machine. An Arduino Mega was used as a controller, data collector, and for evaluating the results. The copper film and TPE 83A material demonstrated significant potential in developing a new flexible sensor for achieving high-accuracy airflow measurement in omnidirectional
Simulation and Parametric Study of a Multiple Effect Distillation with Thermal Vapour Compression
Full text linkDesalination plants are widely used in industrial applications, such as oil and gas, food and beverage, and power generation industries, to produce clean water for internal use. This gives industries greater control over their water security. The project aims to simulate the mathematical model for a Multiple Effect Distillation with Thermal Vapour Compression (MED-TVC) with constraints, incorporating mass and energy balances and the seawater’s thermodynamic properties. The model was simulated using MATLAB to compare the production rate of clean water and gain output ratio (GOR) with different configurations of the desalination system. Input factors considered in the simulation include seawater to evaporator feed flow rate, seawater intake flow rate, seawater salinity, and seawater temperature. The simulation was validated by comparing it with available data of MED-TVC plants from SIDEM with 98.85% accuracy. Results show that the variation in temperature of each evaporator (increment and reduction from -30% to +50% of initial temperature) influences clean water production. Based on the simulation, the vapour output increases as the evaporator\u27s temperature rises, thus increasing the GOR and total distillate production. These findings highlight the critical role of evaporator temperature in optimizing MED-TVC system performance, providing valuable insights for improving industrial desalination processes
Smart Agribot: Advanced CNN-Based Disease Detection in Green Beans with EfficientDet & Auto-Spraying
Full text linkThe Smart Agribot is a cutting-edge robotic system developed to improve how green beans are grown in the Philippines. It combines advanced technology like Convolutional Neural Networks (CNNs) for disease detection, automated spraying, and efficient crop transportation. This project aims to make farming more productive, reduce waste, and improve plant health. The Agribot\u27s physical design uses common, affordable parts like Arduino Uno, Raspberry Pi, metal frames, and wooden supports, creating a sturdy yet cost-effective machine. Its brain is a CNN model trained on a large set of images showing healthy and diseased green bean plants. This training allows the Agribot to accurately identify different plant diseases. Extensive testing confirmed that the system can reliably detect diseases, with especially high accuracy in spotting Rust, a common issue in bean crops. The Agribot’s automatic sprayer further reduces the amount of chemicals needed by only spraying plants that truly need it, which lowers costs and lessens environmental harm. Additionally, the built-in crop transporter makes harvesting faster and more efficient without significantly affecting crop yields. Together, these features make the Smart Agribot a promising tool for modern farming. It can help farmers save time, reduce costs, and improve overall productivity. As the Agribot continues to be improved, it has the potential to work with other crops and farming systems, supporting more sustainable agriculture in the future
An Investigation into Strength Prediction of Columns Strengthened with CFRP Using Artificial Neural Networks
Full text linkThis study presents an investigation into the strength prediction of columns strengthened with Carbon Fiber Reinforced Polymer (CFRP) using Artificial Neural Networks (ANNs). The research aims to develop a reliable predictive model for estimating the ultimate load-carrying capacity of CFRP-strengthened columns by considering key influencing parameters. A dataset comprising numerical results was used to train and validate the ANN model. The selected input parameters included column length, column diameter, steel tube thickness, concrete compressive strength, steel yield strength, CFRP ultimate tensile strength, CFRP thickness, and the number of CFRP layers. The ultimate axial strength served as the output parameter. The developed ANN model demonstrated high accuracy in predicting the column strength, capturing the nonlinear relationships among the variables effectively. The results confirm that artificial neural networks can serve as a powerful tool for structural strength prediction, reducing the need for extensive experimental testing and offering valuable insights for engineering design and assessment
How Heat Waves Influence Project Performance in the Construction Industry?
Full text linkHeat waves in Southeast Asia are becoming increasingly common and intense, posing substantial challenges for the construction industry. As the heat waves are predicted to increase in the future, they will certainly impact construction project performance, specifically in terms of cost, time, and quality. This paper aimed to analyze the impact of heat waves on these project performances. A questionnaire survey using Microsoft Forms was used to gather the data. This paper focuses on 200 respondents from Grade 6 (G6) and Grade 7 (G7) contractors in Johor Bahru, Johor. The findings show the interrelated effects on time, cost, and quality. The productivity of workers decreased as they required a longer time to rest, which led to delay issues. Additionally, exposure of the material to heat and workers\u27 focus on work influence the poor quality of the project. The heat forcing in additional safety measures and heat-related illnesses necessitate more labor, further escalating project costs. Therefore, the paper concludes that heat waves influence construction in Malaysia through an increased duration cost and risk of project completion associated with quality
Peranan Kepimpinan Terhadap Peningkatan Kemahiran Generik dalam TVET untuk Kebolehpasaran Graduan : The Role of Leadership in Enhancing Generic Skills in TVET for Graduate Employability
Full text linkMalay:
Kepimpinan merupakan elemen penting dalam pembangunan kemahiran insaniah atau generik, terutamanya dalam konteks Pendidikan dan Latihan Teknikal dan Vokasional (TVET). Kemahiran seperti komunikasi, penyelesaian masalah, kerja berpasukan, kepimpinan serta professionalisme adalah kritikal untuk memastikan pelajar TVET mampu memenuhi keperluan pasaran kerja yang dinamik. Walaupun kemahiran kepimpinan dianggap sebagai salah satu daripada 5 asas kemahiran generik, kemahiran ini mempunyai pengaruh besar dalam membentuk kemahiran generik lain. Sehubungan dengan itu, objektif utama kajian ini adalah untuk meneroka kajian teori berkaitan peranan kepimpinan terhadap peningkatan kemahiran generik dalam TVET untuk kebolehpasaran graduan. Kajian ini menggunakan kaedah Systematic Literature Review (SLR) untuk meneroka kaitan antara amalan kepimpinan dan peningkatan kemahiran generik dalam kalangan pelajar TVET untuk kebolehpasaran graduan. Proses kajian melibatkan pencarian literatur daripada pangkalan data utama seperti Scopus, Web of Science, Research Gate dan lain-lain, dengan menggunakan kata kunci berkaitan. Daripada kajian literature 21 artikel telah dipilih, hasil analisis menunjukkan bahawa sifat kepimpinan memberi kesan positif dalam membina kemahiran insaniah dan generik pelajar, terutamanya dalam bidang TVET. Hasil kajian ini juga memberikan panduan kepada pemimpin institusi TVET, pembuat dasar, dan penyelidik untuk membangunkan strategi yang lebih terarah dalam meningkatkan kemahiran generik pelajar yang mampu meningkatkan kebolehpasaran graduan, melalui pendekatan kepimpinan yang strategik.
English:
Leadership is a critical element in the development of soft or generic skills, particularly in the context of Technical and Vocational Education and Training (TVET). Skills such as communication, problem-solving, teamwork, leadership, and professionalism are essential to ensure TVET students meet the dynamic demands of the job market. Although leadership is considered one of the five core generic skills, it has a significant influence on shaping other generic skills. In this regard, the primary objective of this study is to explore theoretical studies on the role of leadership in enhancing generic skills within TVET for graduate employability. This study adopts the Systematic Literature Review (SLR) method to investigate the relationship between leadership practices and the improvement of soft skills among TVET students, focusing on graduate employability. The research process involved reviewing literature from major databases such as Scopus, Web of Science, ResearchGate, and others, using relevant keywords. From the literature review, 21 articles were selected. The findings indicate that leadership traits positively impact the development of students’ soft and generic skills, particularly within the TVET domain. This study provides valuable insights for TVET institutional leaders, policymakers, and researchers to develop more targeted strategies for enhancing students’ generic skills, thereby improving graduate employability through strategic leadership approaches
Sustainable Reinforced Prestressed Alkali-Activated Concrete Beams Using Industrial Wastes: An Experimental Investigation
Full text linkIn an era where the sustainability of the construction industry is of prime importance, alternatives to cement are a matter of urgency. In today’s era, alkali-activated concrete (AAC) which is a widely researched area, offers a viable alternative to cement concrete; it has the potential to utilize industrial waste as source material. The current study delves into assessing the impact of prestressing force on both reinforced AAC and reinforced ordinary cement concrete (OPCC) beams. Industrial wastes that serve as primary constituents for AAC are slag and fly ash, which in the present investigation are activated using sodium-based activators. The concrete is developed using ambient curing with a compression value of 40 MPa to achieve sustainability. Analysis of deflection, load-carrying capacity, and failure characteristics was conducted on the reinforced concrete beams in unprestressed and prestressed states, encompassing both reinforced AAC and reinforced OPCC variety of beams. In comparison to reinforced AAC beams, OPCC beams had 18.9% higher strength in flexure, but the deflection was 53.3% higher for AAC beams with rebars. In prestressing conditions of beams, the reinforced OPCC beams had 22.5% more load-carrying capacity compared to reinforced prestressed AAC beams but had 26.2% more deflection compared to reinforced OPCC beams. Thus, sustainable reinforced concrete beams can be manufactured from industrial waste, having very good flexural behavior and load-carrying capacity.
The Potential Use of Ground Ceramic Tile Waste as Partial Cement Replacement in Mortar
Full text linkIn line with sustainable development goals, waste generated from the construction industry that increases annually need to be well managed to ensure environmental sustainability. Ceramic waste is type of solid waste generated at construction site and disposed at landfill which contribute towards environmental pollution. The present research investigates the effect of ground ceramic tile as a partial cement replacement on properties of mortar. Six mixes consisting 0%, 10%, 20%, 30%, 40%, and 50% of ceramic tile powder by weight of cement were tested. The mixes were subjected to setting time test, flow table test, compressive strength and water absorption test. Inclusion of tile powder up to 50% increases the final setting time, but not more than 6.5 hours. Upon blending 10% and 20% tile powder, the flowability value of mortar mixture reduced slightly from 190mm to 185mm and 180mm respectively. The inclusion of 20% tile powder produces mortar with compressive strength of 39.50MPa due to the pozzolanic reaction of the powder. Success in integrating ceramic tile waste as cement replacement would reduce quantity of waste disposed and promotes a cleaner environment