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The purpose of this study is to conduct an investigation into the potential characteristics of Pistia stratiotes at different maturity stages. The focus of interest was to specifically look at oleophilicity properties based on contact angle (CA) measurement.

The morphological characteristics were also examined using a variable pressure scanning electron microscope. Three different oils, namely, Bio Oil 1, Bio Oil 2 and MP-R 10W/40 semi-synthetic oil, were tested on the Pistia leaf surface to measure the CA and wetting properties.

It was found that both types of bio oils had distinct CA values compared to that of the synthetic oil. A maximum difference of 65° to 75° was recorded in CA values.

Based on the results, the maturity of leaves was found to affect the CA values.

An optimized model is often deployed to reduce trial and error in experimental approach and obtain the multi-variant correlation. In this study, response surface methodology (RSM), namely, Box–Behnken design (BBD) approach, has been used to optimize the characterization of lubricant with additives. BBD is based on multivariate analysis whereby the effects of different parameters are considered simultaneously. It is a non-linear system which is more representative of the actual phenomenon. This study aims to investigate the effect of three independent variables, namely, speed, load and concentration of TiO₂, on the coefficient of friction (CoF).

RSM was applied to get the multiplicity of the self-determining input variables and construct mathematical models. Mathematical models were established to predict the CoF and to conduct a statistical analysis of the independent variables’ interactions on response surface using Minitab 16.0 statistical software. Three parameters were regulated: speed (X₁), load (X₂) and concentration of TiO₂ (X₃). The output measured was the CoF.

The result obtained from BBD has shown that the most influential parameter was speed, followed by concentration of TiO₂ nanoparticles and then normal load. Analysis of variance indicated that the proposed experiment from the quadratic model has successfully interpreted the experimental data with a coefficient of determination R² = 0.9931. From the contour plot of BBD, the optimization zone for interacting variables has been obtained. The zone indicates two regions of lower friction values (<0.04): concentration between 0.5 to 1.0 Wt.% for a speed range of 1,000 to 2,000 rpm, and load between 17 to 20 kg for a speed in the range of 1,200 to 1,900 rpm. The optimized condition shows that the minimum value of CoF (0.0191) is at speed of 1,782 rpm, load of 20 kg and TiO₂ concentration of 1.0 Wt.%.

In general, it has been shown that RSM is an effective and powerful tool in experimental optimization of multi-variants.

The purpose of this paper is to investigate the origin and evolution of total quality management (TQM) and lean manufacturing (LM) in the automotive industry globally and specifically in Malaysia; and selective studies on effective performance measurement for future integration of TQM and LM. The paper examines critical success and failure factors of the implementation stage based on established quality criteria, such as in the Deming Prize Award, Malaysian Prime Minister Award, ISO/TS16949, Malcolm Baldrige National Quality Award, SAEJ4001 and Toyota Production System.

The paper takes the form of a review of the literature on TQM and LM, utilizing journal articles, reports, books and theses.

Based on reviewed papers, it was noted that TQM and LM originate from Japan. TQM started from a Company Wide Quality Control Program initiated by Deming, while LM originated from the Toyota Production System. Both terms were coined by the west for global acceptance in 1985. It was also gathered that the evolution of LM started much earlier than that of TQM. Since then, voluminous studies have been conducted on TQM and LM but mostly independently. It was found that an integrated approach combining both TQM and LM has not been fully explored. This is especially evident in the context of the automotive industry in Malaysia. It is then believed that the need to examine this integrated initiative in the Malaysian scenario is imminent. This review paper is a preliminary work for future study to establish the standing of the automotive industry in Malaysia with respect to implementing integrated TQM and LM practices.

Suitable for implementation by practitioners, especially in the Malaysian or Asian automotive industry.

The paper is the first to study the Malaysian automotive industry, which integrates ISO/TS16949 with four TQM awards and two LM systems.

For moderate pressure and high pressure gear pumps, the temperature failure problem of bearings is now of considerable concern because of their heavy loads. However, the compact structure and the efficiency consideration make it extremely difficult to improve the bearing cooling. A self-circulating oil bearing system is developed for gear pumps with self-lubricating bearings to solve this problem. The oil is aspirated in from the low pressure chamber of the gear pump and discharged to the same chamber by using the pressure difference in the journal bearing, thus achieving the self-circulation.

An experiment test rig has been built for the feasibility study. The oil flow rate under different speeds has been recorded. Furthermore, the temperatures of the bearings with or without the oil circulation have been compared. Additionally, the oil flow in the test rig has been simulated using computational fluid dynamics codes.

The experimental and numerical results agree well. The experimental results indicate that the oil flow rate increases approximately linearly with the speed and the bearing temperature can be lowered successfully. The calculation results indicate that the bearing load capacity is nearly the same. Both the experimental and numerical studies establish that the self-circulating oil bearing system works successfully.

As far as the authors know, it is the first time to find that the self-circulation can be built using the pressure difference in the bearing oil film, and this principle can be applied in the cooling and lubrication of the gear pumps to solve the temperature failure problem.