Development of the four-cylinder moving mesh model for A 1.6 litre four-stroke direct-injection engine

The design of a modern internal combustion engine requires the use of advanced analysis and development tools to carry out an in-depth investigation on internal combustion process and computational fluid dynamics (CFD) simulations by using high performance computers. In this work, the algorithm for moving or deformed mesh for a 1.6-litre four-cylinder four-stroke direct-injection engine has been developed. This type of mesh is required for transient simulation of fluid flow and combustion process inside the combustion chamber of an internal combustion engine. This mesh deforms with the movement of intake and exhaust valves as well as piston. Hence, the purpose of the work is to verify the moving mesh algorithm and to establish the correct mesh configuration at any crank angle. The simulation covers the full engine cycle consisting of intake, compression, power and exhaust strokes and the order of piston motion is set according to the firing order of the selected engine. The algorithm established defines events in which any of the designated engine component moves in terms of time and duration of occurrence. The verification of the algorithm was performed for the whole four-stroke cycle of 720 degree crank angles, where the positions of the intake valve, exhaust valve, cylinder and piston were updated accordingly with respect to crank angle. The finalised algorithm and mesh can be used to simulate the in-cylinder fluid flow and internal combustion process for the full engine cycle

General Scenario of COVID-19 Pandemic Waste Management in Malaysia: A Review

Malaysia recorded 880,782 cumulative confirmed cases of coronavirus disease 2019 (COVID-19) and 6,613 deaths as of July 15, 2021. The impact of the high number of infections and movement control order (MCO), Malaysia experienced a 60% to 70% increase in total household waste generation and 120% to 150% increase in healthcare waste. This study aims to conduct a systematic literature review on the general scenario of COVID-19 pandemic waste management in Malaysia. The research methodology is by referring to the literatures in the scholar sites including Scopus, Web of Science and Malay Language journals using the Preferred Reporting Items for Systematic Reviews and Meta-Analyzes (PRISMA) model. English journals were screened using the Central Access Database for Impact Assessment (CADIMA) software, while Malay journals screening was conducted using the Academia.edu search engine. The screening results found that a total of 43 articles out of 571 articles were identified to meet the study criteria. The findings of this study present the pandemic situation in Malaysia, the impact on waste management, the updating of guidelines by the World Health Organization (WHO) as well as the flow of waste management procedures throughout the COVID-19 pandemic period. This study provides insights into the infectious waste management implemented in Malaysia, elucidating how waste management affects the spread of infection and necessary information on healthcare waste management procedures that have been updated by WHO (2020). Proposed further study on the waste management process in depth based on the guidelines that have been updated by WHO (2020) in health centers, residential areas and public places.</jats:p

A Study on the Perception of Architects on The Implementation of Green Roofs in Malaysia: Benefits, Obstacles and Recommendatiosn

The implementation of a green roof as a sustainable method to reduce the urban heat island effect is still new in Malaysia. Although it has not been tested on a city scale, many studies have found that green roofs can balance the impact of urbanization by improving environmental quality. Its low usage in Malaysia is due to various factors, such as cost and the lack of awareness among the construction industry players. This study aims to identify the perceptions of local architects towards the implementation of green roof and its benefits, obstacles and recommendations to overcome the challenges in implementation. Questionnaire survey were used to determine the views of local architects, on ten benefits, nine obstacles of green roof implementation and eight recommendations to overcome the green roofs obstacles. The results indicated that the most important green roof benefit was minimizing the urban heat island effect (N = 8.14). Meanwhile, the weakest green roof benefit was increasing the roofing thermal insulation (N = 3.73). The most significant obstacle of green roof application was the constraint of implementation by the client (N = 4.22), with the weakest obstacle was inadequacy in the confidence of the architect towards the benefits of the green roof (N = 2.62). In addition, the most significant recommendation to overcome its implementation obstacles was enhancing the incentive to green roof operators (N = 4.37), while the weakest recommendation is by bringing in foreign expertise and technology transfer (N = 3.65). The findings of the study will facilitate in promoting the implementation of green roofs in Malaysia and enhancing the contribution of the green roof to the interior and exterior environment of buildings.</jats:p

Correlation Analysis and Multilinear Regression Model for Prediction on Solid Waste Generation in Malaysia

Increased volumes of solid waste generation continue unabated due mainly to rapid population increase, urban migration, economic enhancements, and modern lifestyles. Two significant factors contributing directly to the higher volumes of solid waste generation are population and gross domestic product (GDP). In Phase 1 of this study, a correlation analysis with a Pearson coefficient of more than 93% (r &gt; 0.93) shows a strong positive linear relationship between the amount of solid waste generation and population and GDP. Phase 2 provides a multilinear regression analysis and the development of a regression model. They indicate that a 1-unit increment in the amount of solid waste generation is caused by 0.06 of the population and 0.119 of GDP while ßo remains constant at 124.449. Therefore, the multilinear regression model in this study can be applied by solid waste management authorities in Malaysia to accurately forecast future solid waste generation volumes. However, further investigation on other significance factors are suggested for future work in order to develop a holistic model for solid waste management in Malaysia.</jats:p

Investigation of Disruption Management Practices and Environmental Impact on Malaysian Automotive Supply Chains: A Case Study Approach

Much focus on managing a supply chain in the event of disruption has been on the financial consequences and the service level impact on the customers. The negative impact caused by the disruption could influence a company’s profit and market share. Nonetheless, the importance of the environmental impact consideration in the supply chain disruption management has not been emphasised in the existing literature despite research findings that highlight the impact of some resilient supply chain practices on its environmental sustainability. This paper aims to assess the relationship between supply chain mitigation and recovery practices and its environmental impact. To achieve this objective, a case study was employed where semi-structured interviews were conducted at selected automotive companies in Malaysia. The results show that most disruption mitigation and recovery practices of a supply chain have a medium impact on its environmental performance. In particular, the production process during supply disruption recovery has the highest influence on environmental performance in the form of waste generation and use of energy. The results of this study can be used by supply chain managers to focus their efforts in the right direction in order to achieve cost objectives, service levels and environmental goals during the management of disruptions.</jats:p

Critical Risk Factors of Joint Venture Projects in the Oil and Gas Industry

The Oil and Gas (O&amp;G) industry is one of the riskiest, most dynamic and challenging industries and plays a vital role in every nation’s economy. Like any other major industry, O&amp;G is exposed to a host of both predictable and unpredictable risks. Joint venture projects (JVP) are often regarded as a risky business as there is a high failure rate among them because of the complexities involved. This paper aims to identify the critical risk factors (CRFs) of JVPs for O&amp;G between Malaysia and Thailand. Via systematic literature review (SLR) the risk factors for O&amp;G and JVPs around the globe are identified and a set of questions relating to them were designed and used in a pilot study. A total of 15 respondents from different background experiences working in O&amp;G JVPs were requested to answer the designed questionnaire during the pilot study. The questionnaire survey passed the required Cronbach Alpha value of 0.6 with a score of 0.98. The data collected involved 170 respondents currently working or have worked in O&amp;G JVPs. The relative importance index (RII) for each risk factor’s (RF) value was quantified and the RFs ranked based on the value. A RII value exceeding 60% is considered to have agreement and of importance to the respondents. The RII value can be used as an indicator to rank the RFs from the most to the least critical. The CRF categories determined in this study are environmental, cultural and social, and organisation. Under environmental, the main CRFs are losses due to fluctuations in exchange rates/interest rates. For cultural and social, the main CRFs are problems associated with cultural differences and cooperation. Organisational issues related to organisational fit, incompetent project management team, difficulty in finding and keeping skilled workers, and low worker productivity. All the listed RFs underwent a comprehensive study on their impact and probability of occurrence to determine the best processes, methods, and tools for managing the risks. It is recommended that key players in the O&amp;G industry consider all the RFs of JVPs during the risk management evaluation stage.</jats:p