Technical University of Malaysia Malacca

Universiti Teknikal Malaysia Melaka (UTeM) Repository
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    9008 research outputs found

    Multi-objective optimization of bio-base grease using hybrid taguchi-grey relational analysis

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    Bio grease has gained increasing attention in recent years due to its promising benefits, which include being environmentally friendly, renewable, less toxic, and readily biodegradable. In recent years, numerous studies have been conducted to explore the potential of bio-based greases for industrial applications. This study aimed to create a novel bio-based gease with.a viscosity comparable to a commercial, industrial lubricant. A multi-optimization strategy was utilized to achieve this goal, specifically the Taguchi methodology with grey relational analysis. A total of nine different samples were produced by combining non-edible base oils and different percentages of beeswax thickener and hBN. additives. The optimal blend was then tested for its coefficient of friction and time durability. A greater endurance over time will reflect reliability for application, especially in robust industries. The study employed the Taguchi optimization technique with grey relational analysis to evaluate how diverse design parameters influenced the friction coefficient. According to the findings, the optimal blend of ingredients was 92.5% castor oil, 5% beeswax thickener, and 2.5% hBN additives, resulting in the highest friction coefficient that falls within the range of conventional industrial lubricants. This study contributes to the growing body of research on bio base greases and their potential for industrial applications and demonstrates the effectiveness of a multi-optimization approach using Taguchi with Grey relational analysis. By pursuing this effort, developing and implementing innovative approaches centred on resource conservation will lead to a sustainable future where we can thrive without depleting our planet's limited resources

    Analysis of repetitive repair welding on properties on stainless steel to carbon steel dissimilar metal joints

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    Repair welding of dissimilar material is frequently used in steel structures to replace the weldment defect and prolong the material service life. Generally, repair welding is a crucial topic that needs more discussion due to the lack of application in real industry. In order to reduce cost and dependence on the high skilled welders, repair welding on dissimilar pipe materials Stainless Steel 304 (AISI 304) and Carbon steel 1387 (BS 1387) were performed using Gas Metal Arc Welding (GMAW) with 100 mm each long. Furthermore, dissimilar is not just the material but also the diameter of the pipes. Fixed nozzle rotational jig was used as the main welding equipment with current (A), voltage (V) and rotational speed (rpm) as the main parameter. The study was focused on the effect of repair welding on mechanical properties, microstructure formation of AISI 304 and BS 1387 and prediction of service life of the dissimilar material repaire welded pipes. Tensile, microhardness, and fatigue tests were performed with nine runs of samples with three times of repetition as a planning matrix generated by Minitab Software. Design of Experiment (DOE) was used to plan the whole project using Taguchi Method as the main platform. Prediction of tensile testing and fatigue testing failure location was performed using ANSYS software. The outcome of the study shows that repair welding affected the performance of weldment, especially on mechanical properties. Tensile and microhardness testing showed the highest value on the second repair, while fatigue testing on the third repair. The heat generated during the welding process also affects the Heat Affected Zone (HAZ), and the microstructure formation of them was discussed. The regression equation of each repair was generated, and validation error was calculated. Prediction of the pipe service life schedule was performed using an FMEA chart in order to have a proper preventive maintenance schedule

    Citizen-centric adoption model for smart government among United Arab Emirates public users

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    Tremendous advancements in information and communication technology, coupled with the usability of smart mobile devices, have brought enormous growth in the appeal of highquality government services. This appeal has, in turn, encouraged governments to deploy services to citizens using a smart government channel. Worldwide, governments have recognized the need to deliver better-integrated services to the public to meet their expectations. Therefore, the transition from the conventional modes of delivering government services to a smart government format involves substantial considerations in the operational aspects of services delivery and drastic changes in existing core business systems across governmental public institutions. The concepts of smart government and smart services have emerged as new ways to deliver such services to meet citizens’ demands by developing tools and setting practical standards for services delivery. However, the smart government concept is still difficult to adopt in developing countries including United Arab Emirates (UAE) among public users. Although preparations for adopting the smart government concept in UAE have started running, the implementation of this concept is still not optimal.This means that most smart government studies are still focusing on problems in the early stages of the adoption phase. Thus, this study proposes a Citizen-Centric Adoption Model for Smart Governments among UAE Public Users. There are three objectives of this study. The first objective is to determine the attributes of a citizen-centric design model in smart government. Second, to build a new citizen-centric design model for adoption in the UAE smart government among public users. Third, to validate the proposed model in a smart government among public users. The study opted for an exploratory study using a systematic literature study to identify the significant attributes of the proposed model. The research study was conducted in UAE with an estimated sample size of 323 respondents. To develop a citizen-centric model towards public users when using the online information of a smart government, the data were analyzed based on the regression model to test six hypotheses. The results derived show significant values on openness, transparency, responsiveness, usability, and trust, which recorded p-values of 0.010, 0.000, 0.006, 0.005 and 0.000, respectively that implies a significant relationship with influence on enhancing the citizencentric model is accepted, while the hypothesis related to security factor is rejected. Based on the hypothesis testing and analysis, there is a strong relationship between the significant attributes of the proposed model with the significant R-value. Overall, the adoption of a citizen-centric model in enhancing the public user experience when using online information of a smart government can be used by government agencies as helpful resources while adopting a smart government

    EFFECT OF COCONUT FIBER LOADING ON THE ORPHOLOGICAL, THERMAL, AND MECHANICAL PROPERTIES OF COCONUT FIBER REINFORCED THERMOPLASTIC STARCH/BEESWAX COMPOSITES

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    The increasing concern about global warming and the accumulation of non-biodegradable plastic has caused serious environmental issues. Hence, the need to create a more environmentally friendly material such as thermoplastic starch (TPS) has grown. However, the poor properties of TPS, such as high moisture sensitivity and low mechanical properties, have limited the potential application of this biopolymer. This study aims to modify TPS’s thermal and mechanical properties by incorporating coconut fiber. The composites were prepared by incorporating various coconut fiber loading (0, 10, 20, 30, 40, and 50 wt.%) into the TPS matrix. The mixture was fabricated using a hot press at 145o C for 1 hour. The sample is then characterized using thermogravimetric analysis and tensile and flexural tests. The results show that the composite with 50 wt.% coconut fiber had higher thermal stability than samples with lower fiber content. A significant increment in tensile strength and modulus of up to 20.7 MPa and 2890 MPa were recorded for samples with 50 wt.% fiber content—the sample with 50wt.% fiber also demonstrated the highest flexural strength and modulus of up to 30.3 MPa and 3266.3 MPa, respectively. These changes are consistent with the FTIR and SEM findings, which show good compatibility of TPCS and coconut fiber with a homogeneous structure. Overall, coconut fiber shows good potential as reinforcement for biodegradable-based polymer composites

    Exploiting surface plasmon with dielectric coating in copper wires waveguide for the propagation of terahertz waves

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    Recently, metallic wires have gained popularity for utilization as waveguides in propagating sub-THz and THz waves through surface plasmonic polaritons (SPPs). Single and double metallic wire waveguides have demonstrated the ability to propagate these high frequencies with minimal loss and nearly zero dispersion. However, wires typically installed commercially are often coated with dielectric material. Therefore, this paper investigated the effects of using two and four metallic copper wires, both with and without dielectric coating. The impact of various gap distances on different propagation characteristics was also analyzed. Computer Simulation Technology (CST) Microwave Studio was employed in this study for electromagnetic simulations of both uncoated and coated configurations of two and four wires. The introduction of a dielectric coating led to an enhancement in reducing conductor losses and improving energy confinement, with the goal of enhancing the overall efficiency of waveguide signal propagation

    Comparative study on bending and torsional effect of highly thermal graphene hybridization conductive ink

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    Electronic device printing on flexible and rigid substrates is advancing rapidly. Health, advertising, vehicles, transportation, energy, and electronics are among the sectors that employ this technology. Printing ink is an important component of printed electronics technology, with conductive inks being the most commonly used material. In recent years, researchers have investigated the combination of metal nanoparticles with graphene nanosheets. Hybrid conductive graphene inks for electronic applications have increased due to the addition of conductive polymers or metallic nanoparticles to improve graphene's original capabilities. Silver nanoparticle (AgNP) conductive ink dominates all metal-particle-based conductive inks for printed electronics. The objective of this study is to first formulate a new hybridization formulation between GNP and Ag. Besides, this new formulation of conductive ink has been investigated and characterised in terms of electrical and mechanical behaviour. The third was to evaluate the resistance and resistivity of the new conductive ink formulation using bending and torsion tests. Following that, research was carried out on the formulation and performance of GNP hybrids using GNP, silver flakes (Ag), and silver acetate (SA) as conductive fillers mixed with organic solvents to produce powder and paste. Then, the GNP hybrid paste was printed on a copper substrate using a mesh stencil method. The curing process involved in this experiment was 250°C per hour. The resistivity was evaluated at room temperature before the bending and torsional tests. After the test, the GNP hybrid formulation's reliability was evaluated in terms of electrical and mechanical resistivity. The resistivity value before performing the mechanical test was acceptable due to the lowest resistivity value in the range of 0.963 × 10-5 to 1.293 x 10-5 .m at room temperature. The finding exposed that the resistivity values for each of the three samples of bending and torsional tests significantly changed after 1000 cycles. However, the resistivity value of the torsional test at 5000 cycles was increased due to the damage impact of increasing the number of torsion cycles on the sample. Overall, the results revealed that this hybrid conductive ink has good resistivity and performs with acceptable reliability and durability. In future work, it is recommended that the conductive ink be printed on a more flexible substrate than copper, and the evaluation of temperature dependence can also be made more comprehensively

    Boiler tube remaining life according to Larson-Miller parameter

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    This research aims to address the problem of the remaining boiler tube life according to the Larson-Miller parameter (LMP). Boiler tubes are used in a wide variety of industrial applications and are subject of deterioration due to corrosion and other environmental damage. It is estimated that 10% of all power plant breakdowns are caused by creep fractures of boiler tubes. Additionally, 30% of all tube failures in boilers and reformers are a result of creep. This deterioration can cause significant damage to the boiler and its associated equipment, leading to decreased efficiency and increased downtime. Therefore, the evaluation of boiler tube remaining life is essential in order to ensure the continued reliability and performance of the boiler system. The LMP is a widely accepted tool for evaluating the remaining life of boiler tubes which is based on a combination of temperature, stress and time. The LMP is used to calculate the remaining life of boiler tubes and is based on the assumption that the boiler tube will fail when the LMP reaches a certain critical value This research aims to analyse the LMP, its limitations and its ability to accurately predict the remaining life of boiler tubes. From the study it shows that LMP is a theoretical method for estimating boiler tube life based on pressure and temperature, but it does not take into account the boiler's condition or atmosphere. The research also reveals that the highest temperature was associated with the lowest stress level i.e., materials with higher LMP values are more susceptible to severe creep damage and as temperature increased in the boiler, the remaining life of the tube decreased significantly ( the remaining life of a tube SA 213 was less than 300 hours at 1139 K)

    Academic performative measures in higher education a case study in the Universiti Teknikal Malaysia Melaka

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    This case study is about academic performative measures in higher education. In the globalized world whereby rankings, digital technology, and neoliberal reforms have crept into higher education, these have led to an increase in academic workload. Academics are not only burdened with tasks that include teaching and research, but they are also fraught with industrial and community consultations, academic publications, and marketing. As such, this case study aims to describe and analyze the effects and impacts of academic performative measures in a higher education institution, namely at the Universiti Teknikal Malaysia Melaka (UTeM). This study is framed using the case study framework design, utilizing the Constructivist Grounded Theory for data collection and analysis. The views and experiences of the participants were interpreted and analyzed critically and systematically to contribute to research in human resource development and human resource policy reforms in higher education. Through the theoretical sampling method, twelve participants were selected and interviewed. They are comprised of academics who are professors, associate professors, senior lecturers, and lecturers. The interview sessions revolved around themes such as teaching, writing, research, publication, and consultation. The findings of this study reveal that the landscape, scenario, as well as delivery system of higher education, is changing dynamically and rapidly. These changes are influenced mainly by globalization, lack of funding, and neoliberalism centered on the need of industries, businesses, and societies. Lecturers are currently burdened with main tasks involving five (5) main things namely teaching, writing, research, publication, and consultation. The results of the study found that the implementation of academic performative measures has an impact on academics. Some issues related to best practices, personal problems, knowledge and skills of the academics, as well as issues regarding being in a comfort zone, high administrative work, dissatisfaction with university authorities, Key Performance Indicators (KPIs) pressure, psychology, and productivity are some of the key themes that emerge from the results of the study. This study contributes to a better understanding of academic performative measures and practical contributions emphasizing the importance of strategic planning, addressing ethical challenges, fostering networking opportunities, and transforming higher education systems. By addressing these contributions, institutions can better support academics in achieving their KPIs, upholding academic integrity, and responding to the evolving needs of the higher education landscape

    Relay node placement in wireless sensor network for manufacturing industry

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    elay nodes are necessary to maintain scalability and increase longevity as the number of manufacturing industrial sensors grows. In a fixed-budget circumstance, however, the cost of purchasing the bare minimum of relay nodes to connect the network may exceed the budget. Although it is hard to establish a network that connects all sensor nodes, in this case, a network with a high level of connection is still desirable. This paper proposes two metrics for determining the connectedness of a disconnected graph of sensor nodes and determining the optimum deployment method for relay nodes in a network with the highest connectedness while staying within a budget restriction. The metrics are the number of connected graph components and the size of the most significant connected graph component. Prim's algorithm and the approximation minimum spanning tree algorithm are applied to construct a disconnected graph and discover the best relay node placement to solve these two criteria. Compared to the other metrics, simulation findings suggest that prioritizing the most significant connected components in the disconnected graph can yield superior outcomes by deploying the fewest number of relay nodes while retaining the connectedness of the graph

    Low-loss paper-substrate triple-band-frequency reconfigurable microstrip antenna for Sub-7 GHz applications

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    In this paper, a low-cost resin-coated commercial-photo-paper substrate is used to design a printed reconfigurable multiband antenna. The two PIN diodes are used mainly to redistribute the surface current that provides reconfigurable properties to the proposed antenna. The antenna size of 40 mm × 40 mm × 0.44 mm with a partial ground, covers wireless and mobile bands ranging from 1.91 GHz to 6.75 GHz. The parametric analysis is performed to achieve optimized design parameters of the antenna. The U-shaped and C-shaped emitters are meant to function at 2.4 GHz and 5.9 GHz, respectively, while the primary emitter is designed to operate at 3.5 GHz. The proposed antenna achieved peak gain and radiation efficiency of 3.4 dBi and 90%, respectively. Simulated and measured results of the reflection coefficient, radiation pattern, gain, and efficiency show that the antenna design is in favorable agreement. Since the proposed antenna achieved wideband (1.91–6.75 GHz) using PIN diode configuration, using this technique the need for numerous electronic components to provide multiband frequency is avoided

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