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Universiti Kebangsaan Malaysia (UKM) is a research university that continuously undergoes an audit and accreditation process for the management of its courses. The Faculty of Engineering and the Built Environment (FKAB) is subjected to such processes, one of them is the auditing conducted by the Engineering Accreditation Council (EAC), which gives recognition to engineering programmes in Malaysia. The criteria that have been set by the EAC requires the faculty to measure and evaluate graduates based directly on the course outcomes (CO) and programme outcomes (POs) to ensure that they are able to achieve the programme and course objectives. This paper discusses a method developed for the measurement and evaluation of POs which is a direct measurement for assessing the courses offered in the mechanical engineering programme. Assessment templates are developed using a Microsoft Excel based on the data presented on the grade coordination meetings conducted at the end of each semester. The data used for this study were semester 2 2010/2011 session, and semester 1 session 2011/2012. Based on the results obtained, the majority of the courses achieves more than 80% for course level monitoring for their individual PO achievement except for five subjects. For programme level monitoring, from the average POs marks, all POs were scored more than 80%, which indicates that the Mechanical Programs offered by the department are satisfied with the department standard.

One of the major concerns of the Engineering Accreditation Council (EAC) is the need for an effective monitoring and evaluation of program outcome domains that can be associated with courses taught under the Mechanical Engineering program. However, an effective monitoring method that can determine the results of each program outcome using Bloom's Taxonomy has not yet been established for each course. The purpose of this research is to conduct a Big Picture Assessment to achieve Outcome-Based Learning. Big Picture Assessment is a comprehensive monitoring tool of courses with studied program outcome domains. The tool applies the three main domains of Bloom's Taxonomy, namely, psychomotor, cognitive, and affective, in its monitoring process. Furthermore, the identification of program outcomes for each course is evaluated to meet standards set by the EAC. The results of this study will facilitate continuous improvement on existing courses.

Degumming and bleaching are critical steps in the palm oil refining process, as they are the precursors to the qualities of refined, bleached, and deodorized palm oil. In practice, plant operators often face oil rejections in these processes and solve the problem by trial and error. Hence, a fuzzy expert system is developed to troubleshoot the degumming and bleaching process, for identifying failures and suggesting actions. However, developing the knowledge base and inference engine in the fuzzy expert system for troubleshooting the degumming and bleaching process is challenging because the data in the actual palm oil refining process are poorly documented and must be obtained from various sources, including field observation, document analysis, and interviews, and need to be analyzed using thematic analysis. The results from the thematic analysis were represented as input and output variables of the fuzzy expert system. The developed fuzzy expert system is tested and validated against different data sets and industrial data to identify faults and suggest necessary actions. To evaluate the robustness of the troubleshooting system, the membership functions of the fuzzy expert system are adjusted based on the distributed control system (DCS). The results show that the troubleshooting system can effectively diagnose potential faults and provide necessary actions and can serve as a useful guidance for failures in the degumming and bleaching process. [ABSTRACT FROM AUTHOR]

The industry has been significantly enhanced by recent developments in UAV collision avoidance systems. They made collision avoidance controllers for self-driving drones both affordable and hazardous. These low-maintenance, portable devices provide continuous monitoring in near-real time. It is inaccurate due to the fact that collision avoidance controllers necessitate trade-offs regarding data reliability. Collision avoidance control research is expanding significantly and is disseminated through publications, initiatives, and grey literature. This paper provides a concise overview of the most recent research on the development of autonomous vehicle collision avoidance systems from 2017 to 2024. In this paper, the state-of-the-art collision avoidance system used in drone systems, the capabilities of the sensors used, and the distinctions between each type of drone are discussed. The pros and cons of current approaches are analyzed using seven metrics: complexity, communication dependency, pre-mission planning, resilience, 3D compatibility, real-time performance, and escape trajectories. [ABSTRACT FROM AUTHOR]

The behaviour of the steel bar in concrete under cyclic loading has been evaluated using magnetic flux leakage associated with acoustic emission monitoring technique. Visual observation was used to observe the deformation of the beam under cyclic loading. The sensors of metal magnetic memory were scanned in the middle of the beam at a distance of 320 mm at the bottom part. Twenty-two cyclic ranges were performed for cyclic loading of 100 or 200 cycles for each range, with a frequency of 1 Hz and a sinusoidal wave mode. The magnetic flux leakage signal, acoustic emission characteristics and crack width were measured and analysed to evaluate the behaviour of the steel bar in the concrete beam. The magnetic flux leakage signal and acoustic emission energy results were well matched with the occurrence of cracks at the centre of the beam. It was found that the relationship between the magnetic leakage flux signal and crack opening showed a strong correlation with R2 of 0.969. A high acoustic emission energy of 1300 nVs is observed at the centre of the beam. Based on the results, the behaviour of the steel in the concrete beam can be determined by the integrity assessment of a structure. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to determine the best dimple core design for metal sandwich panels by investigating the various critical criteria and core design parameters using the fuzzy-hybrid multi-criteria decision-making tool. The structural integrity of a sandwich panel depends on the core design and significantly affects the bonding strength. The continuous design and testing of a sandwich panel is a very lengthy process that increases the design time. The simulation analysis output was segregated into nine critical failure criteria. All the critical criteria weightages were evaluated using the Fuzzy-Analytical Hierarchical Process, while the Fuzzy—Technique for Order Preference by Similarity to Ideal Solution was used to evaluate the Closeness Coefficient value to determine the best core design configuration. The results indicate that the core configuration with a diameter of 6.0 mm and a depth of 3.0 mm obtained the highest closeness coefficient values, 0.9937 and 0.9294, under cyclic loading conditions of 50% and 70%. It was shown that using average sizes in the dimple configuration tends to provide better delamination resistance and structural integrity. This study contributes to the selection of the optimum core design configuration based on the various design criteria and using non-complex and competent analysis. [ABSTRACT FROM AUTHOR]

This paper presents a modified fatigue life model of the Basquin equation using the stress parameter of the magnetic flux leakage signal. Most pipeline steels experience cyclic loading during service and the influence of the load history makes assessing fatigue behaviour more difficult. The magnetic flux leakage signal's response to a uniaxial cyclic test of API X65 steel was measured with eight levels of ultimate tensile stress loads. The influence of dH(y)/dx on fatigue failure was the main concern in this study, the aim being to represent localised stress parameters in the modified Basquin equation. Both fatigue lives, experimental and predicted from the modified Basquin equation, were validated through reliability analysis, producing a 60% value when approaching 1.8 × 105 cycles. The fatigue data from the experiment produced a higher mean-cycle-to-failure value than the prediction data, with slightly different values of 3.37 × 105 and 3.28 × 105. Additionally, the modified Basquin equation's predicted and the experimental fatigue lives were found to have a high R2 correlation value of 0.9022. The Pearson correlation also showed a good relationship between the fatigue lives, with an r value of 0.9801. Finally, the modified Basquin equation based on dH(y)/dx signals provided an accurate and alternative method for durability assessment. [ABSTRACT FROM AUTHOR]

The aim of this paper is to characterise the fatigue reliability for various random strain loads under extreme value distribution while considering the cycle sequence effect condition in fatigue life prediction. The established strain–life models, i.e., Morrow and Smith–Watson–Topper, considered a mean stress effect and strain amplitude; nevertheless, it excluded the load sequence effect, which involves the fatigue crack closure that is subjected to overload or underload. A FESEM-EDX analysis is conducted to characterise the failure features that occurred on the leaf spring. A finite element is simulated to determine the critical region in order to obtain the strain load behaviour. In addition, the strain signal is captured experimentally at 500 Hz for 100 s under operating conditions for three different road loads based on the critical location obtained from the finite element analysis. The fatigue life correlation shows that the Pearson correlation coefficients are greater than 0.9, which indicates the effective strain damage model is linearly correlated with the strain–life models. The fatigue life data are modelled using extreme value distribution by considering the random strain loads as extreme data. The reliability rate for the fatigue life is reported to be more than 0.59 within the hazard rate range of 9.6 × 10−8 to 1.2 × 10−7 based on the mean cycle to the failure point. Hence, the effective strain damage model is proposed for a fatigue reliability assessment under extreme conditions with higher reliability and provides fatigue life prediction when subjected to cycle sequence effects. [ABSTRACT FROM AUTHOR]

Vibration fatigue characteristics are critical for rotating machinery components such as turbine rotor blades. Lattice structures are gaining popularity in engineering applications due to their unique ability to reduce weight and improve the mechanical properties. This study is an experimental investigation of octet-truss lattice structure utilization in turbine rotor blades for weight reduction and to improve vibration fatigue characteristics. One completely solid and three lattice infilled blades with variable strut thickness were manufactured via additive manufacturing. Both free and forced experimental vibration analyses were performed on the blades to investigate their modal and vibration fatigue characteristics. The blades were subjected to random vibration using a vibration shaker. The response was measured using a triaxial accelerometer in terms of vibration acceleration time histories in the X, Y, and Z directions. Results indicate a weight reduction of up to 24.91% and enhancement in the first natural frequency of up to 5.29% were achieved using lattice infilled blades. The fatigue life of the blades was investigated using three frequency domain approaches, namely, Lalanne, Dirlik and narrow band. The fatigue life results indicate that the 0.25 mm lattice blade exhibits the highest fatigue life, while the solid blade exhibits the lowest fatigue life of all four blades. The fatigue life of the 0.25 mm lattice blade was 1822-, 1802-, and 1819- fold higher compared to that of the solid blade, using the Lalanne, Dirlik, and narrow-band approaches, respectively. These results can serve as the first step towards the utilization of lattice structures in turbine blades, with thermal analysis as the next step. Therefore, apart from being light weight, the octet-truss lattice infilled blades exhibited superior vibration fatigue characteristics to vibration loads, thereby making them a potential replacement for solid blades in turbine rotors. [ABSTRACT FROM AUTHOR]