University of Technology Malaysia

In this paper, a hybrid PV/diesel/battery-based energy system is designed for supplying power to the residential area being fed with diesel generators during outrage hours. The proposed system is utilized generated power from the standalone PV system along with diesel generator to replace the requirement of diesel by solar energy partially. The optimal hybrid system is obtained by using hourly measured solar radiation data and per liter cost of diesel for the selected location along with other required components. Performance analysis is done using Hybrid Optimization Multiple Energy Resources (HOMER). A comparative study based on percentage renewable penetration, total net present cost (TNPC), cost of energy (COE) and emitted pollutants has been carried out. It is found that the system constitutes of three generators of 50 kW, 50 kW and 10 kW along with a PV array of 64 kW and battery of 53 kW is the optimal solution for the selected site. Sensitivity analysis shows that the proposed system, for a diesel price of 1 $/liter and with solar penetration of 34$/kWh and $ 1,042,824 respectively. The presented model can be used in designing optimal energy systems for a similar environment.

With the increased power demand, the effort on the efficiency improvement of the existing renewable systems is also increased. One of the available options is the Solar PV-T cogeneration system. Such systems provide an alternative to utilize the extracted heat from the panel. As the electrical efficiency of the PV system mainly depends on the panel used and the power electronics converter efficiency. The panel efficiency increases with the reduction in panel temperature for particular isolation. And the reduction in power losses in the inverter can be achieved by reducing the number of device count of the inverter topology. For this, an efficient multilevel inverter (MLI) topology and nanofluid-based solar PV panel is proposed. The proposed panel uses TiO2 Nano-fluid as the cooling agent. The prototype of the developed panel is tested in the laboratory in which a decrease in panel temperature of 18.7 °C is achieved. Performance of the panel is compared with other experimental studies available as well as with water and airflow fluid in the same environmental condition. Results show that the proposed panel can absorb 27% more heat than airflow panel, and the improvement of about 1.17% in the efficiency of the panel is achieved. An efficient and reliable inverter topology focusing on utilizing a single source is proposed. The developed circuit structure is compared with other existing seven-level topologies, and it is found that the proposed topology utilizes only one dc source with the lowest device count, thus have lower losses. Performance of the system incorporating the developed PV panel and the proposed inverter is verified through required simulation analysis. Results obtained shows that the integrated system works properly with lower converter losses and panel efficiency of 16.38%. Therefore the proposed system is efficient and very much suitable for solar PVT applications.

Road traffic crashes are a global concern, claiming 1.2 to 1.3 million lives annually, with a significant impact on low- and middle-income countries, where they account for 80% of such fatalities and result in economic losses of around 5% of GDP. The increasing number of motor vehicles exacerbates this issue, making road traffic crashes the leading cause of death for individuals aged 15–29 years in these regions. Due to this gap, this study focuses on Malaysia, where motorcyclists represent the highest number of road traffic fatalities. By surveying 500 motorcyclists from high-risk districts in Selangor state—Petaling Jaya, Shah Alam, and Kajang—this research aims to evaluate the effectiveness of road safety measures and policy enforcement. The methodology targets motorcyclists aged 16–40, providing a balanced gender representation to offer comprehensive insights into enhancing road safety for this vulnerable group. Hence, the findings indicate that the level of enhancing road safety among motorcyclists is moderate. This situation urges that the current rules need to be updated to address the challenges in today’s globalized world.

Surface excavation works in tropically weathered rock are often reported to be challenging due to too many uncertainties such as rock mass and rock properties, environment, selection of the best excavation method, machine characteristics, cost and production rate. The purpose of this study is to present an overview of previous assessments of excavatability and demonstrate the reliability of these methods for assessing the weathered state of rocks in tropical regions. In surface excavation operations, the heterogeneity of the rock mass presents significant issues, particularly in sedimentary locations where the same rock mass contains multiple rock layers with varying weathering grades and strengths. Furthermore, the non-bedded rock mass displays a distinct profile, with boulders occurring throughout the entire zone of highly weathered rock. In tropical weathered rocks, the weathering profile of the rock mass can be very erratic, changeable, and dominant in dictating the behavior of the rock. Disputes in rock engineering properties for practitioners involved in construction work, due to weathering and other issues such as the complex behavior of soil-like and rock-like material arise at the site. These disputes affect practitioners working in the field. A critical review of the current excavatability assessment was conducted. The parameters are then contrasted with the current excavatability assessment procedure, and the outcomes are also specified. At the end of the study, the significance parameter on geological, geotechnical, and geophysics could be determined for various types of rock; thus a reliable classification system could be proposed for efficient assessment. Additionally, a classification system that takes into account the geological factors that are important for surface excavation in tropical areas is greatly needed to assess excavatability.

The impact of pollution on insulator surface performance has been extensively studied to continuously improve the insulator performance using suitable condition monitoring, including using the leakage current harmonic component analysis. However, the analysis of harmonic components, particularly in relation to the odd harmonics of the leakage current in aged insulators under the influence of contamination and humidity, is still not fully understood and remains deficient. In this paper, the leakage current of aged and polluted insulators under different environmental conditions are investigated. The study was conducted experimentally using twelve samples of insulators with varying degrees of aging. The crest factor was employed as an indicator of the leakage current index. The findings showed that the odd harmonic crest factor demonstrates high sensitivity in classifying the degree of aging in contaminated insulators.

A critical bone tissue engineering (BTE) strategy is fabricating porous scaffolds using simple and straightforward techniques. However, all porous structures share a common drawback, reduced strength due to porosity. Furthermore, bone scaffolds are vulnerable to bacterial infections when implanted, especially in compromised bone conditions. In this study, baghdadite (BAGH) scaffolds were developed and coated with gelatin (Gel)-reduced graphene oxide (RGO)-azithromycin (AZM) with suitable porosity (75–80%) and pore size (600–800 μm) using the space holder method, combined with a dip coating process in a low vacuum condition. The outcomes revealed that incorporating the Gel-RGO layer increased the compressive strength from 0.8 to 2.9 MPa for the Gel-RGO-AZM scaffolds. The scaffolds coated with Gel-RGO-AZM demonstrated improved bioactivity compared to their uncoated counterparts, showcasing the ability to generate hydroxyapatite (HA)-like crystals after a 28-day soaking period in simulated body fluid (SBF). In vitro studies validated the antimicrobial effectiveness of co-released RGO and AZM from Gel-RGO-AZM coated scaffolds against E. coli and S. aureus bacteria. Moreover, the coated scaffolds exhibited significantly improved cellular responses. In conclusion, the research results show that the developed BAGH scaffolds coated with Gel-RGO-AZM are promising materials for BTE, offering enhanced compressive strength, bioactivity, biocompatibility, and antibacterial performance.

A significant portion of the world’s population relies on rice as a primary source of nutrition. In Malaysia, rice production began in the early 1960s, which led to the cultivation of the country’s most significant food crop up till the present day. Research on various aspects of the price and production of rice has been done by various methods in the past. In this study, we have adopted novel multivariate fuzzy time series models (MFTS) i.e. fuzzy vector autoregressive models (FVAR) alongside conventional vector autoregressive model (VAR) for assessing rice price and production using a dataset from the Malaysian Agricultural Research and Development Institute (MERDI). The proposed method(s) especially with the usage of Trapezoidal Fuzzy Numbers (TrFNs) have commendable accuracy with great future forecasts over the VAR model. The model selection was made by the least MAPE with the corresponding highest Relative Efficiency as criteria. The study fills the gap in applying advanced fuzzy models for rice forecasting, aiming to improve accuracy using fuzzy vector autoregressive (FVAR) models with Triangular Fuzzy Numbers (TFNs) and Trapezoidal Fuzzy Numbers (TrFNs) over traditional VAR models. The study’s findings imply that the enhanced forecasting accuracy of FVAR models with Trapezoidal Fuzzy Numbers (TrFNs) can significantly assist local farmers and stakeholders in making informed decisions about production and pricing. This improved forecasting capability is expected to promote business growth within the Malaysian market and facilitate increased rice exports, ultimately contributing to the country’s economic prosperity.

The escalating air pollution resulting from traffic congestion has necessitated a shift in traffic control strategies towards green and low-carbon objectives. In this study, a graph convolutional network and self-attention value decomposition-based multi-agent actor-critic (GSAVD-MAC) approach is proposed to cooperative control traffic network flow, where vehicle carbon emission and traffic efficiency are considered as reward functions to minimize carbon emissions and traffic congestions. In this method, we design a local coordination mechanism based on graph convolutional network to guide the multi-agent decision-making process by extracting spatial topology and traffic flow characteristics between adjacent intersections. This enables distributed agents to make low-carbon decisions which not only account for their own interactions with the environment but also consider local cooperation with neighboring agents. Further, we design a global coordination mechanism based on self-attention value decomposition to guide multi-agent learning process by assigning various weights to distributed agents with respect to their contribution degrees. This enables distributed agents to learn a globally optimal low-carbon control strategy in a cooperative and adaptive manner. In addition, we design a cloud computing-based parallel optimization algorithm for the GSAVD-MAC model to reduce calculation time costs. Simulation experiments based on real road networks have verified the advantages of the proposed method in terms of computational efficiency and control performance.

In cardiovascular therapeutics, procedures such as heart transplants and coronary artery bypass graft are pivotal. However, an acute shortage of organ donors increases waiting times of patients, which is reflected in negative effects on the outcome for the patient. Post-procedural complications such as thrombotic events and atherosclerotic developments may also have grave clinical implications. To address these challenges, tissue engineering is emerging as a solution, using textile technologies to synthesize biomimetic scaffolds resembling natural tissues. This comprehensive analysis explains methodologies including electrospinning, electrostatic flocking, and advanced textile techniques developed from weaving, knitting, and braiding. These techniques are evaluated in the context of fabricating cardiac patches, vascular graft constructs, stent designs, and state-of-the-art wearable sensors. We also closely examine the interaction of distinct process parameters with the biomechanical and morphological attributes of the resultant scaffolds. The research concludes by combining current findings and recommendations for subsequent investigation.

With an increasing prominence of electric vehicles (EVs) in sustainable transportation, it demands a robust and steady charging infrastructure. The widespread adoption of EVs into the transportation ecosystem hinges on continuous and reliable operation of charging stations (CSs). This paper delves its focus on reliability and resilience of EV chargers using various fault-tolerant (FT) techniques. It also analyzes the EV chargers’ failure scenarios such as hardware malfunctions and power outages which can disrupt the charging process. To evaluate these strategies, advanced FT algorithms and system reconfiguration protocols has been analyzed. Also, Total Harmonic Distortion (THD) act as key performance indicator which indicates the reduction from 60% to -40% with diminished current and voltage variations and enhanced grid stability. The extensive real-world research and simulations on charging scenarios reflects the key performance metrics with 95% charging efficiency and fault recovery times of 0.8 seconds at 180 Volts. This research evaluates the compatibility and cost-effectiveness of these strategies with diverse EV models. Ultimately, the findings highlight the effectiveness and practicality of FT techniques for EV chargers providing valuable insights for infrastructure developers and ensures a reliable EV charging fostering consumer trust and accelerating the global transition to electric mobility.

Can simulating the public transit experience of individuals with mild visual impairments promote empathy in design college students, thereby facilitating their design decisions? The purpose of this study is to explore the impact of a mixed empathy intervention (role-playing and experiential prototyping) on improving design students’ empathic ability and design decisions. The Basic Empathy Scale (BES) and a Design Decision Questionnaire (DDQ) were used to evaluate the empathy and design decision-making of design students (n = 51). Paired sample t-tests, Pearson correlation, and linear regression were used for quantitative analysis of the intervention effects, combined with text mining techniques. Key findings include: 1) The empathy intervention significantly improved students' empathy levels (t = − 2.976*); 2) The cognitive empathy level of students was enhanced (t = −2.276*), specifically in terms of cognitive dimensions, depth, and breadth; 3) The empathy intervention significantly affected students' views on the importance of related design elements (t = − 2.958*); 4) Empathy improvement explained around 36.5% of the variation in design decisions. These findings suggest that during a design practice and education method, role-playing and experiential prototyping can not only help students understand the target users but also enhance their consciousness on design service, thus upgrading their design decisions.

Increasing attention has been paid on the utilization of non-ferrous metallurgical slags (NFMS) for the synthesis of alkali-activated materials, which offers sustainable solution for slag disposal, reduces natural resources consumption, and improves eco-friendly development of construction industry. This work extensively reviews the recycling of NFMS, macro- and micro- properties of NFMS-based geopolymers, contribution chemical compositions for geopolymerization and related mechanism.

Although numerous studies have examined the direct association between academic stress and problematic smartphone use, the empirical evidences for the association are inconsistent. Also, the factors that can mediate or moderate the association remain underexplored. With the aim to address these knowledge gaps, based on 680 undergraduate students recruited from Universiti Teknologi Malaysia (UTM), this study has examined (1) the direct association between academic stress and problematic smartphone use, (2) the mediating role of escapism motivation on the association between academic stress and problematic smartphone use, (3) the moderating role of present hedonistic time perspective on the association between escapism motivation and problematic smartphone use, and (4) the moderating role of present hedonistic time perspective on the indirect association between academic stress and problematic smartphone use through escapism motivation. The findings have shown that (1) the association between academic stress and problematic smartphone use was not statistically significant, (2) the association between academic stress and problematic smartphone use was mediated by escapism motivation, (3) present hedonistic time perspective has positively moderated the association between escapism motivation and problematic smartphone use, and (4) present hedonistic time perspective has positively moderated the indirect association between academic stress and problematic smartphone use through escapism motivation. The current study identified escapism motivation and present hedonistic time perspective as the factors that can explain “how” and “for whom” academic stress causes problematic smartphone use and provided important practical implications for the intervention of problematic smartphone use among undergraduate students.

In a consequence of climate change’s adverse effects, Malaysia’s road infrastructure faces significant challenges, particularly during both dry and rainy seasons, which weaken the natural bonds of the laterite soil. This research, therefore, outlines a laboratory study aimed at assessing the impact of cement stabilisation on the compressibility characteristics of laterite soil, subject to both saturated and unsaturated conditions. This study reveals that a 6% cement dosage is optimal for stabilising the laterite soil, proving the minimum 7-day strength requirement of 800 kPa, as specified by the Malaysia Public Works Department (MPWD) for stabilised subgrade material in low-volume roads. Consequently, the research involved conducting saturated tests (utilising a conventional oedometer) on soil specimens stabilised with 3%, 6%, 9%, and 12% cement dosages. Meanwhile, only the 6% cement-stabilised soil is used in unsaturated tests with a modified suction-controlled oedometer. The findings of this study highlighted that cement-stabilised laterite soil exhibits significantly lower compressibility in comparison to unstabilised laterite soil. Furthermore, the unsaturated oedometer test demonstrated that soil’s compressibility is notably decreased at higher suction levels (drying conditions) compared to lower suction levels (wetting conditions). In summary, this research contributes valuable insights, emphasising the potential of cement as an effective soil stabiliser by reducing soil settlement and enhancing the durability of Malaysia’s roads in response to climate-related challenges.

Exploring the relationship between discrimination perceptions and subjective well-being among college students with disabilities and the chain-mediated effects of psychological resilience and positive coping styles. Questionnaires were administered to 528 college students with disabilities using the Discrimination Perceptions Scale, Index of Well-Being Scale, Psychological Resilience Scale, and Simple Coping Styles Scale. SPSS 24.0 and Amos 26.0 were used to analyze chained mediation effects and construct structural equation modeling tests. ①Discrimination perception was significantly negatively correlated with subjective well-being (r = -0.294, p < 0.01), psychological resilience(r = -0.427, p < 0.01) and all 3 of its dimensions, and positive coping styles (r = -0.328, p <0.01); subjective well-being was significantly positively correlated with psychological resilience (r = 0.334, p < 0.01) and all 3 of its dimensions, and positive coping styles (r = 0.363, p<0.01); and positive coping styles was significantly positively correlated with psychological resilience(r = 0.433, p < 0.01) and all 3 of its dimensions.② The direct effect of discrimination perceptions on college students with disabilities was significant, and the mediating effect value was-0.191.③Psychological resilience and positive coping styles not only play a significant separate mediating role between discrimination perceptions and subjective well-being of college students with disabilities, with mediation effect values of -0.138 (49.11%) and − 0.087 (30.96%), respectively but also play a significant chain mediating role between discrimination perceptions and subjective well-being, with an effect value of -0.056 (19.93%). Discrimination perceptions can directly affect the subjective well-being of college students with disabilities, and can also indirectly affect the subjective well-being of college students with disabilities through the separate and chain-mediated effects of psychological resilience and positive coping styles.

This paper reports the influence of gold nanoparticle (Au NPs) concentration variation on the physical properties of some Sm³⁺/Dy³⁺ co-doped zinc-sodium tellurite glasses. These glasses with composition of (58.8–z) TeO2–25ZnO–15Na2O–0.8Sm2O3–0.4Dy2O3–zAu (where z = 0.02, 0.04, 0.06, 0.08, and 0.10 mol%) were prepared via the melt-quenching approach and characterized. The obtained samples were transparent and amorphous. An increase in the glass density and refractive index was observed with the increase of Au NPs concentrations. FTIR and Raman spectra of the glasses identified vibration modes related to various chemical functional groups. The temperatures for the glass transition, crystallization, and melting were changed with the variation of Au NPs contents. The optical absorption spectra of the glasses showed 16 characteristic peaks (in the range of 350–1700 nm) of Sm³⁺ and Dy³⁺ transitions together with the localized surface plasmon absorption peak of Au NPs. The luminescence spectra under 380 nm excitation showed five significant peaks around 400–750 nm. The fluorescence lifetime decay profiles and Commission Internationale de l'éclairage (CIE) 1391 color chromaticity diagram exhibited the corresponding moderate white-light emission and color purity, indicating the white-light-emitting potency of the proposed glass system. It was surmised that by controlling Au NPs contents, the optical characteristics of the glass system can be customized.

In recent years, the conversion of methanol to olefins (MTO) over acidic zeolite catalysts as a non-petroleum alternative for producing light olefins has attracted considerable interest. This paper comprehensively reviews recent advancements in modifying SAPO-34 and ZSM-5 zeolites for MTO reaction and performs a bibliometric analysis to gain insight into trends in the field. The study covers the utilization of zeolites in MTO technology, elucidating the process flow configuration and emphasizing the pivotal factors affecting the zeolite catalyst performance in conversion of methanol to olefin. The various modifications of SAPO-34 and ZSM-5 catalysts are extensively discussed, focusing on the intricate modifications such as alterations in the silicon-alumina ratio, utilization of structure directing agents, creation of core–shell structures, and introduction of metals. The catalyst modification significantly affects MTO outcomes, with various alterations showing the potential to enhance selectivity, propylene-to-ethylene ratio, and catalytic stability, offering prospects for selective light olefin production in the MTO process.

This systematic literature review examines the current state of accounting employability research, focusing on required skills, challenges, and initiatives to enhance graduate preparedness. Following PRISMA guidelines, 45 relevant studies were analysed. Key findings highlight the growing importance of a diverse skill set for accountants, including professional skills, soft skills, digital skills and strategic competencies. Meanwhile, a significant gap remains between employer expectations and graduate competencies. The review identifies several initiatives to bridge this gap, such as work-integrated learning and curriculum reforms. The study also highlights barriers to implementation, including limited resources, the need for faculty development, and challenges in engaging students. It suggests directions for future research, recommending efforts that focus on policy development, teacher motivation, curriculum improvements, and student engagement to strengthen accounting education and enhance graduate employability. This review provides insights for accounting practitioners, accounting students, educators, employers, and policymakers to enhance accounting education and improve employability in a rapidly evolving professional landscape.

The underexplored halophilic genus Joostella within the Flavobacteriaceae family consists of only two species, both of which have received little attention for their potential biotechnological applications. In this study, we report the isolation and characterisation of a novel halophilic bacterium, strain CR20, using a genomic approach to investigate its biotechnological potential. Analysis of the 16S rRNA gene revealed that strain CR20 shares 97.5% and 96.2% sequence similarity with Joostella marina DSM 19592 T and Joostella atrarenae M1-2 T, respectively. Strain CR20 exhibited average nucleotide identity and digital DNA-DNA hybridisation values of 76.8–79.1% and 20.8–22.8%, respectively, with Joostella spp., which fall below the species delineation thresholds. Additionally, strain CR20 demonstrated average amino acid identity and percentage of conserved proteins values of 81.3–84.0% and 71.7–75.3%, respectively, with Joostella spp., above the genus delineation thresholds. Meanwhile, the average amino acid identity and percentage of conserved proteins values of strain CR20 against Galbibacter spp. are 73.9–80.0% and 61.3–72.3%, respectively, also above the genus delineation thresholds. These findings indicated strain CR20 has a close relationship with both genera. Chemotaxonomic analysis of strain CR20 identified predominant fatty acids, including iso-C17:0 3OH (25.3%), iso-C15:0 (14%), and C16:1ω6c/C16:1ω7c (12.2%). The assembled genome comprises 62 contigs, with a size of approximately 3,168,727 bp and a G + C content of 35.1%. Among 2,804 predicted genes, 2,559 were classified into 25 COG functional groups. A total of 68 genes with potential industrial applications were identified, including 1 β-mannanase, 2 β-xylosidases, 1 polysaccharide deacetylase, 4 other hemicellulases, 6 β-glucosidases, 25 proteases, and 29 phosphate-solubilising enzymes. Hydrolytic assays confirmed that strain CR20 produces these enzymes extracellularly. These findings highlight strain CR20 has potential for industrial applications.