Journals of Universiti Tun Hussein Onn Malaysia (UTHM)
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Enhanced Performance of Millimetre-Wave Dual-Polarized Antennas Through Reduced Element Spacing
Get PDFThe increasing demand for higher data rates and better signal quality in 5G wireless networks has driven the advancement of dual-polarized antennas, which offer improved channel capacity and enhanced MIMO capabilities. Nevertheless, challenges such as achieving sufficient isolation, compact form factors, and effective beamforming remain, especially in millimeter-wave (mmWave) applications. This study introduces an enhanced single-layer, dual-polarized patch antenna with slant ±45° polarization, operating at 28 GHz. Designed to optimize performance while maintaining a compact structure, the antenna significantly reduces inter-element spacing — from approximately 57 mm to 15 mm. It is built on a Rogers RT5880 substrate and incorporates a T-power divider for efficient signal distribution. Both simulation and experimental results confirm improvements in reflection coefficient, radiation patterns, and gain compared to earlier designs. The antenna achieves a reflection coefficient of less than -10 dB, indicating strong performance, with measured gains ranging from 3.7 to 7.8 dBi. The revised radiation patterns display reduced sidelobe levels and a more directional main beam in the co-elevation azimuth plane, highlighting the effectiveness of the reduced spacing. These enhancements make the proposed design well-suited for 5G mmWave applications, particularly for beam-steering systems. Future developments can build on this work to further optimize performance in high-frequency wireless networks
Design and Fabricate of 3D Printed X-Band Sample Size Based Polyethylene Terephthalate Glycol (PETG) Rectangular Waveguide
Get PDFThis work discusses the design and fabrication of 3D-printed dielectric materials for rectangular waveguides, with specific attention given to the effects of infill density and pattern changes on dielectric attributes. Microwave CST Studio is used to design the waveguide structures, which were produced through additive manufacturing and later tested with a two-port rectangular waveguide measurement system. The S-parameters were measured using a Keysight PNA-L Network Analyzer N5234B, whereby the reflection coefficient (S11) and the transmission coefficient (S21) were measured to determine how the material interacts with electromagnetic waves. It was found that greater infill densities correlated with increased values of real permittivity, whereas infill patterns have an essential influence on the material\u27s dielectric behavior. Several patterns were tested: concentric, cross, cubic, and zigzag; the zigzag pattern gave the best results concerning the effective permittivity, while the concentric pattern presented the least because of the greater air gaps. The strong dependence of permittivity on infill density illustrates the possibility of controlling dielectric properties through additive manufacturing using PETG material. It has been demonstrated that 3D printing methods can fabricate waveguides and RF circuits that enable control over dielectric properties
Flow Channeling And Restriction Zone Identification in Gas Mask Filter Cartridges using CFD
Get PDFGas mask filters are critical for protecting against hazardous gases and airborne pollutants, yet their performance is strongly influenced by internal airflow behavior. In this study, Computational Fluid Dynamics (CFD) was employed to investigate pressure drop, velocity distribution, and air age (residence time) within a gas mask cartridge. The simulations revealed a maximum pressure drop of 41.94 Pa, well within acceptable breathing resistance limits, but with non-uniform distribution across the absorbent bed. Velocity contours showed flow channeling forming near the inlet and outlet, leaving regions further from the outlet underutilized. Air age analysis confirmed these patterns, with some regions achieving the required 0.67–0.80 s contact time for effective adsorption, while others fell below this threshold. Under humid conditions, resistance increased, leading to longer residence times but reduced overall airflow renewal. These findings highlight that both cartridge can affect airflow uniformity, adsorption efficiency, and sorbent utilization. The findings can guide the optimization of filter design in achieve more balanced flow distribution and improved performance.
 
Emerging Technology Entrepreneurship Trends And Performance Multinational Organisations in Nigeria
Get PDFDespite the key role in driving economic development using investment by multinational organisations, such as the creation of jobs, and technology transfer, many multinational organisations in Nigeria face infrastructure shortfall, weak institutional setup, and socio-economic instability. This study aims to examine emerging technology entrepreneurship trends and the performance of multinational organisations in Nigeria by closing these gaps by exploring the link between entrepreneurial orientation, technology infrastructure, human capital and the performance of multinational organisations in Nigeria. The study adopts a descriptive survey design to investigate the impact of emerging technology entrepreneurship trends on the performance of multinational organisations. The study targets operational and managerial employees of multinational companies in the telecommunication sector with subsidiaries in Osun State, Nigeria. The study employs a systematic random sampling technique. Given the infinite population approach, the sample size is predetermined as 385 respondents based on Cochran\u27s formula (1977). A structured questionnaire was designed to gather relevant information. Descriptive and inferential statistics were utilised in the study for the data techniques. The results reveal that entrepreneurial orientation significantly impacts the performance of multinational organisations. Technology infrastructure was not statistically significant and human capital emerged as a critical predictor of organisational performance. The research recommended that multinational organisations operating in emerging markets, such as Nigeria, should tailor their strategies to address local challenges.
Building Safety Regulations in The Construction of Housing Projects
Get PDFBuilding safety regulation was become the main issue in the construction industry because of the increased rate of death and injury among workers in the workplace. This research aims to identify effective safety compliance towards the Occupational Safety and Health (OSHA) by developers and consultants to minimise the risk in the construction of housing projects. The objective is to explore the importance of building safety regulations in the construction of housing projects. The interview session has been conducted among developers and consultants in the construction industry, which are currently involved in construction of housing projects. All the data collected were examined utilising theme analytic techniques. The study has identified that there were six (6) themes of impacts with non-compliance with safety regulations, (1) Financial penalties, (2) Loss of productivity, (3) Damage to the end loss of materials, plant, and equipment, (4) Time loss, (5) Endangering lives and (6) Industry disqualification. This findings will be able to determine the effects of non-compliance with safety regulation requirements in the construction of housing projects
Ethical Improprieties During the Procurement Stage in The Malaysian Construction Industry
Get PDFThis paper examines critical ethical challenges in procurement within Malaysia\u27s construction industry, focusing on issues like transparency lapses, bid rigging, bribery, and collusion. These unethical practices are attributed to weak systems, unclear ethical standards, and inadequate awareness of regulations, particularly in complex procurement processes. The study evaluates the determinants, consequences, and preventive measures for such violations, emphasizing the significant economic, reputational, and regulatory impacts. Data was collected from construction stakeholders, including developers, consultants, contractors, and government agencies, using a quantitative survey methodology. Results reveal that ineffective management, poor legislation, and weak governance are primary contributors to unethical behavior. Major consequences include a pervasive culture of bribery and corruption. Recommended preventive measures include strict penalties such as fines, suspensions, blacklisting, and enforcing severe legal actions like imprisonment to uphold integrity and transparency
Development of a Chef Uniform Ethics Learning Kit Using Augmented Reality (AR) for Hearing Impaired Students in Polytechnics
Get PDFHearing-impaired students face difficulties in understanding the ethics of wearing the chef uniform due to limited communication, lack of standardized sign language terms, and insufficient interactive teaching aids. These challenges reduce their understanding and motivation in learning, highlighting the need for more visual and engaging learning tools. The purpose of this study is to develop a chef uniform ethics learning kit using Augmented Reality (AR) for hearing-impaired students, with a focus on enhancing their visualization, understanding, and motivation through a more interactive and accessible learning experience. The study employs a Design and Development Research (DDR) approach and uses the Analysis, Design, Development, Implementation, and Evaluation (ADDIE) model as the instructional design framework. The sample consists of 10 hearing-impaired students enrolled in their second semester of the “Sijil Khas Operasi Katering” program at Politeknik Ibrahim Sultan (PIS), Johor. The findings indicate that the use of the AR-assisted learning kit significantly improves the visualization, understanding, and motivation of hearing-impaired students in understanding chef uniform ethics. The levels of visualization, understanding, and motivation of hearing-impaired students demonstrated high achievements after using the AR-assisted learning kit. Additionally, no significant differences were found between male and female hearing-impaired students, suggesting that the AR-assisted chef uniform ethics learning kit benefits all hearing-impaired students equally, regardless of gender. The results of this study highlight the potential of AR in supporting inclusive education and improving learning outcomes for students with special needs, offering an innovative approach for future educational tools in vocational programs. In conclusion, this study emphasizes the positive impact of AR in creating an inclusive, engaging, and effective learning environment for hearing-impaired students, in alignment with the goals of inclusive education in Malaysia.
Sejarah Dunia dari Kacamata Alam Melayu: Satu Tinjauan Epsitemologi Alternatif: World History from the Perspective of the Malay World: An Alternative Epistemological Review
Get PDFMalay:
Artikel ini bertujuan untuk meninjau sejarah dunia melalui lensa pandangan alam Melayu sebagai satu usaha epistemologi alternatif dalam memahami naratif sejarah global. Wacana sejarah dunia sering didominasi oleh naratif Eurocentrik yang meminggirkan suara dan pengalaman peradaban bukan Barat, termasuk tamadun Melayu. Melalui pendekatan analisis kualitatif berbentuk kajian kepustakaan dan pemikiran kritikal, artikel ini mengemukakan pandangan alam Melayu sebagai satu kerangka epistemologi yang berasaskan nilai, tradisi, dan pengalaman lokal yang unik. Penulisan ini menelusuri bagaimana alam Melayu membentuk interaksi antarabangsa melalui jaringan perdagangan, penyebaran Islam, dan hubungan diplomatik sejak zaman silam. Artikel ini mencadangkan bahawa epistemologi Melayu mampu menyumbang kepada penulisan sejarah dunia yang lebih inklusif, adil, dan pelbagai suara, sejajar dengan usaha dekolonisasi ilmu dan pengiktirafan terhadap naratif alternatif dalam wacana akademik global.
English:
This article aims to explore world history through the lens of the Malay worldview as an effort towards an alternative epistemology in understanding the global historical narrative. The discourse on world history is often dominated by Eurocentric narratives that marginalize the voices and experiences of non-Western civilizations, including the Malay civilization. Through a qualitative approach involving literature review and critical thinking, this article presents the Malay worldview as an epistemological framework grounded in unique local values, traditions, and experiences. This paper traces how the Malay world shaped international interactions through trade networks, the spread of Islam, and diplomatic relations since ancient times. The article argues that Malay epistemology can contribute to a more inclusive, equitable, and multi-voiced account of world history, in line with the broader efforts of decolonizing knowledge and recognizing alternative narratives within global academic discourse
Community Empowerment Through Social Service: The Role of Sacrificial Animal Slaughter in Strengthening Solidarity and Economic Resilience in Sidoharjo Village, Pulung Ponorogo
Get PDFThe slaughter of sacrificial animals (qurban) is a religious practice in Islam that carries profound spiritual significance alongside its broad social and economic dimensions. This study aims to analyze the implementation of social service activities through qurban slaughter in Sidoharjo Village, Pulung, Ponorogo, and its impact on strengthening social solidarity and empowering the local economy. Using a qualitative approach with a case study method, the research involved direct observation during the activity, in-depth interviews with organizers, community leaders, and beneficiaries, as well as documentation analysis. The findings reveal three key impacts of qurban activities in Sidoharjo Village. First, in the social aspect, the activity fosters community solidarity through active participation in all stages, from fundraising and animal slaughter to meat distribution. Second, the meat distribution contributes significantly to food equity, particularly for underprivileged groups who have limited access to protein sources. Third, the activity positively impacts the local economy, benefiting livestock farmers who experience increased demand for sacrificial animals. Moreover, community involvement in managing the event creates temporary economic opportunities, such as roles in logistics and slaughter operations. This study highlights the importance of qurban slaughter as a community service model that integrates religious values with social harmony and economic empowerment. The findings provide valuable insights for implementing similar programs in other communities, emphasizing structured management to maximize their impact
Heat Transfer Enhancement in Single Heat Exchanger 2D Pipe Using Rod with Different Angles Based on Computational Fluid Dynamics Study
Get PDFThe current numerical study focuses on the statistical investigation of the airflow and the improvement of the heat transfer rate by forced convection of a single pipe in a heat exchanger by the inclusion of a rod. Using the finite volume method by numerical simulation the flow characteristics of the working fluid with enhanced heat transfer are numerically studied. Homogeneous heat flux is applied to the upper and lower walls of the pipe. More for the Reynolds number range (9000-18000) the effect of inserting a rod inside the tube at different oblique angles (40°,50°, and 60°) was examined. Numerical results revealed that the transfer coefficient rate (Nusselt number) increase in the tube inserted into the rod is higher compared to the normal pipe. In addition, the results also showed that when the angle of inclination of the rod in the single-pipe heat exchanger is gradually increased the Nusselt number increases. The Nusselt number maximum value was shown at the 60° angle of the rod insert. Because of the resistance of a bigger flow, the friction factor was found by using the rod inserts at (60°) and pitch distance (0.04 m). For a minimum slant angle of (40°) and a pitch distance of (0.04 m), the maximum value of the performance evaluation criteria (PEC) was stated. In comparison to the smooth tube, the percentage of fluid velocity distribution rises by (50,57, and 63%) at the angle of inclination of the rod (40°, 50°, and 60°), respectivel