Universiti Teknologi Malaysia

About: Universiti Teknologi Malaysia is a education organization based out in Johor Bahru, Malaysia. It is known for research contribution in the topics: Membrane & Adsorption. The organization has 21644 authors who have published 39500 publications receiving 520635 citations.

Mixed CUSUM-EWMA chart for monitoring process dispersion

Abstract: Every industrial process has to encounter two types of variation in product characteristic(s) that can be classified as common and special cause variations. These variations can exist in any parameters (like location, dispersion, shape, etc.) of the distribution of process characteristic. To handle the special cause variations, statistical tools are generally used to handle these special cause variations; statistical control chart is one of them. The most famous control charts are Shewhart, exponentially weighted moving average and cumulative sum charts, and their substantial modifications are available in the literature. In this article, we have proposed a new control chart named as mixed CUSUM-EWMA (called MCE) control chart for the efficient monitoring of process dispersion. The proposed MCE chart is compared with other existing control charts and some of their modifications. Average run length, extra quadratic loss, relative average run length, and performance comparison index are the measures that are used to judge the performance of charts. For practical considerations, an illustrative example with real data is also provided.

Two-stage cultivation strategy for simultaneous increases in growth rate and lipid content of microalgae: A review

Abstract: The depletion of fossil fuels and the search for novel sustainable energy sources are challenges faced by countries throughout the world over the past few decades. Microalgae have received considerable interest as new oil sources for biofuel production. However, the enhancement of the lipid content in microalgae strains without decreasing the growth rate is a prerequisite for improving the economic viability of microalgae-derived biofuel production. The implementation of an appropriate cultivation strategy can increase both lipid accumulation and biomass production. One of the most-often suggested strategies is the cultivation of microalgae through two-stage cultivation strategy (TSCS). This paper aims to recapitulate the findings of recent studies and achievements in improving the lipid productivity and economic feasibility of TSCS. This article starts by highlighting different types of TSCS based on various stimuli. Afterwards, the most noteworthy culture parameters, including growth stage and initial cell density, are addressed. The existing experimental results show that lipid productivity can be enhanced by optimizing stress factor(s) and engineering processes. Moreover, it is reported that the modification or elimination of the pre-harvesting phase (which can be done by upgrading technical aspects and/or via stress induction strategies) can promote the economic feasibility of TSCSs.<

Critical success factors for Malaysian construction projects: an empirical assessment

Abstract: Although extensive research has been undertaken on the critical success factors (CSFs) for construction projects, very little of this research contains information specific to the local context. While several local studies have been conducted within a similar research boundary, variables with growing importance in the literature, the human-related factors, have yet to garner much attention. Therefore, the main objective of this study was to gain a renewed understanding of the emerging trend of CSFs considered by various stakeholders in the local industry. This was achieved through a comparative study of 48 Malaysian construction stakeholders classified into three categories, namely, developers, consultants and contractors. The Kruskal-Wallis one-way analysis of variance (ANOVA) on 46 factors suggests that the stakeholders favour a more balanced approach to CSFs. Apart from the 'hard' factors, there is a strong consistency among the perception of project stakeholders in recognizing the significance of human-related 'soft' factors. The analysis further reveals that the high scoring factors are mostly related to three major aspects: (1) project personnel; (2) commitment and communication; and (3) site management and supervision. Implementation of human-related factors will help to stimulate an atmosphere of trust among stakeholders amidst a widespread adversarial attitude in the industry.

Land Subsidence Susceptibility Mapping in South Korea Using Machine Learning Algorithms.

Abstract: In this study, land subsidence susceptibility was assessed for a study area in South Korea by using four machine learning models including Bayesian Logistic Regression (BLR), Support Vector Machine (SVM), Logistic Model Tree (LMT) and Alternate Decision Tree (ADTree). Eight conditioning factors were distinguished as the most important affecting factors on land subsidence of Jeong-am area, including slope angle, distance to drift, drift density, geology, distance to lineament, lineament density, land use and rock-mass rating (RMR) were applied to modelling. About 24 previously occurred land subsidence were surveyed and used as training dataset (70% of data) and validation dataset (30% of data) in the modelling process. Each studied model generated a land subsidence susceptibility map (LSSM). The maps were verified using several appropriate tools including statistical indices, the area under the receiver operating characteristic (AUROC) and success rate (SR) and prediction rate (PR) curves. The results of this study indicated that the BLR model produced LSSM with higher acceptable accuracy and reliability compared to the other applied models, even though the other models also had reasonable results.