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Industrial equipment reliability can be improved through understanding the underlying root causes of system failures and by implementing the predictive maintenance strategy. Failures and maintenance activities data are normally available in industries; however proper failure causes analysis is still lagging. As such, the benefits of predictive maintenance strategy could not be realised. This has contributed to high operational and maintenance cost and not sustainable in the long term. The objective of the paper is to propose a customised predictive maintenance model for minimising the overall maintenance cost of centrifugal pumps in an oleo-chemical plant in Johor, Malaysia. About 14% of total maintenance cost in this plant was attributed to centrifugal pumps related maintenance. Currently, repeated components failures were solved through firefighting without addressing the actual root causes. In this study, the Failure Modes Effects and Criticality Analysis (FMECA) was used to identify critical components interactive failures, namely the mechanical seal, bearing and shaft of the centrifugal pumps. The failure distribution functions for the series reliability structure was formulated after thorough statistical tests on the historical data. The potential benefit of the proposed model is illustrated with alternative maintenance interventions to achieve acceptable pump reliability levels at minimum cost. The findings from this study should be beneficial to maintenance practitioners and researchers toward achieving sustainable operations. [ABSTRACT FROM AUTHOR]

This paper present results of a study that investigate students with different level of mathematics anxiety in solving mathematics problems. The sample of the study involved 120 students from four primary schools in Kulaijaya district, Johor, Malaysia. Data collected through survey-based questionnaires. The instruments adapted include Mathematics Anxiety Scale, A Study on Level of Problem Solving Skills and Choices of Problems. Findings indicate that there is a significant relationship between mathematics anxiety and problem-solving skills among the students. It was found that the reasons for choosing a problem to solve first by students with high mathematics anxiety include easy problem, understand the problem, minimum time required, maximum time required, minimum working required, difficulty of the problem, liking, order of the problem, confidence, interesting, short question, and lower order thinking required. The high mathematics anxiety students assert the choice made in choosing the problems was based on their mathematics problem solving skills. Further reflection on their emotions or feelings on choosing which problem to solve first relate to confident, feeling successful and satisfied. While choosing the last question to solve is associated with the feeling of stress, anger, and frustration. The findings highlighted a concern in addressing mathematics anxiety among primary school students, considering these students are still at the early stage of formal education. [ABSTRACT FROM AUTHOR]

The aim of this paper is to model the non-stationary Generalized Extreme Value distribution with a focus on Bayesian approach. The location parameter is expressed in terms of linear trend over the time period while constant for both scale and shape parameters. This study also explores the informative and Jeffrey's prior towards the efficiency of the estimating procedure. Root Mean Square Error is then use for choosing the best prior. Metropolis Hasting for extreme algorithm will also briefly explained in this study. The model is applied to the air quality data for Johor state. [ABSTRACT FROM AUTHOR]

Public transport is one of the methods to reduce traffic congestion. At present, around 61,000 buses are operating all over Malaysia. Most of these buses are run by diesel which led to the contribution of greenhouse gases emissions. To tackle this issue, Battery Electric Bus (BEB) is one of the solutions to reduce carbon emissions as well as traffic congestion. Even though some major cities already implemented and used BEB to solve the issue, but it is quite unusual to use BEB in the rural area, especially here in Malaysia due to some factors. Limited by driving range, BEB needs to spend some time to be recharged at a certain range. In Malaysia, there is around 309 charging station already make available to be used for the electric vehicle around the peninsular by ChargEV Malaysia. However, most chargers can only be accessed around the major cities, making it quite difficult and costly to implement in the rural area. Thus, a study will be conducted to do electric bus planning for rural transportation. The study will be constructed based on the same number of trips and a similar existing route by Perbadanan Pengangkutan Awam Johor (PAJ). Numbers of routes will be taken randomly all over Johor and two routes will be chosen which are situated in the rural area and have the longest route as well as take the longest time to reach the destination by considering the typical traffic along the route. Proper analysis is conducted to utilize onboard solar PV (OBSPV) for electric buses which may be able to reduce the stops time required at charging stations to charge the battery and increase the range of electric bus mobility. Using General Algebraic Modelling System (GAMS) an optimization software, the bus planning will be optimized to determine the proper scheduling of the bus (to reduce the waiting time of the passenger) as well as the economic impact to implement the project. From this, no additional charging station will be required other than the bus terminal itself. Besides that, a case study of electric buses with and without OBSPV is also will be presented. The environmental impact will be analysed as well by comparing the implementation of BEB and the existing diesel bus in terms of CO2 emission. [ABSTRACT FROM AUTHOR]

This study aims to examine the teachers' frequency on using games, facilities as well as equipment provided towards teachers' preference in choosing the type of games. This case study deployed a full qualitative approach via interviews with three preschool teachers from three different schools in one of the districts in Johor. The sampling was selected randomly through snowball process. The interview data was analyzed manually in order to identify for the themes. The data gathered was then validated through peer r eview. Results of the analysis show that, preschool teachers hardly used games in their teaching and learning. Apart from that, the preschools did not have proper ICT equipment to be used in the teaching and learning process. It was found that, the respondents preferred to use the non-digital materials rather than digital material. The research was able to measure the importance of the frequency of using games by teachers, the ICT facilities and equipment prepared has led to teachers' choice of using non-digital materials with the preschoolers. [ABSTRACT FROM AUTHOR]

Pedestrian are vulnerable road users who have high potential to encounter traffic hazard. Therefore, an evaluation of pedestrian's safety is considered as one of the important components to prevent road traffic injuries. This study was conducted to evaluate the pedestrian level of awareness and compliance behaviour at urban area. Two data collection methods, by questionnaires survey and video recording, were adopted in the research. The questionnaires survey collected data on the pedestrian's level of awareness exploring their level of knowledge, their attitude towards the pedestrian facilities provided and their awareness about their own safety when using the varying types of pedestrian facilities. At the same time, we conducted video recording to assess the pedestrians risk taking and compliance behaviour towards the pedestrian facilties. Several locations with high pedestrian traffic at Central Business District in Johor and Penang, Malaysia were selected as the study areas. The results show a similar trend of pedestrian level of awareness and travelling behaviour towards various pedestrian facilities for both cities which indicating that pedestrians' compliance behaviour does influence by varying types of pedestrian facilities. [ABSTRACT FROM AUTHOR]

In order to provide accurate solar irradiation approximation, and to quantify solar energy; the dependencies between solar irradiation, sunshine hours and ambient temperature must be taken into account. The amount of daily irradiation received for a particular area is among the most important meteorological parameters for numerous application fields. The utilization of accurate distribution minimizes the degree of uncertainty in solar resource estimates. This study applies the copula method for solar radiation estimation. This particular method is useful where probability of marginals fit into various families of distributions. The Archimedean copula and Gaussian copula were applied to evaluate solar irradiation in Johor Bharu, Malaysia. The solar irradiation, sunshine hours and ambient temperature were fit into five marginal probability distributions, namely, Gamma, Lognormal, Burr, Weibull and Normal distributions. The optimal fit marginal probability distribution was assessed by selecting the lowest possible value for Akaike Information Criterion (AIC). Finally, the bivariate copula best fit distribution was combined to obtain at the triavariate joint probability distribution. The results indicate that the best fit of joint probability between solar irradiation, sunshine hours and ambient temperature is Clayton copula. [ABSTRACT FROM AUTHOR]