Numerical study of variable length exhaust pipe in small engine

Small engines, with capacity not exceeding 150 cc, can be divided into two types: two-stroke and four-stroke engines. The exhaust pipe has significant influences on the performance of the engine. Thus, it is necessary to study factors that affect the exhaust in order to improve the performance of the engine. For this early stage, it would be appropriate to conduct the research by using simulations since they only require minimal resources and can be conducted in a short period. The objective of this study is to conduct the simulation for determining the required velocity and pressure in the exhaust pipe. The comparison is done between parameter values from different configuration of exhaust pipes; the most appropriate configuration is then proposed. Three types of exhaust pipe is proposed using computer software and simulations are carried out using ANSYS Workbench 15.0. Results show that the velocity and pressure fluctuate according to the diameter and length of the exhaust pipe. Model 3 exhaust pipe configurations have been selected as the most suitable exhaust pipe for obtaining the maximum pressure and velocity

Review on the status of theory and research of social media studies in Malaysia: a conceptual paper

In the recent years, the literature indicated that adoption and consequences of using social media on the users and society has become a popular topic among the communication scholars. However, past studies also show that prior efforts in discussing on the stature and scholarship of social media research in Malaysia is scarce. Thus, the purpose of this conceptual paper is to review on the theoretical patterns and research trends of social media related studies on Malaysian users. In particular, the method used is based on literature reviews in chronological order concerning new media, social media and research trends analyses from journal articles, thesis proceedings and conferences, book and more. A framework of analysis was generated to identify the frequency and occurrences in theoretical application, research topic areas, methodological approaches, types of contents, social media medium of interest and research developmental phases of social media studies. The study ends with summaries and recommendations to utilise comprehensive content analyses of communication and media journals in Malaysia to trace the theoretical trends and research patterns pertaining to social media research

Research on the state of social media studies in Malaysia: 2004-2015

In the recent years, the advancement of social media plays a phenomenal role in the Malaysia’s media and academic landscape. Social media have garnered massive adoption among the online population, paving way for scholars to understand on the usage and impact of social media on the users in the country. The rising amount of research on social media illustrates a growing interest in this phenomenon. Despite the budding interest among scholars, the understanding on the research patterns and status on social media studies in Malaysia is still inadequate, comparing with the research trends analyses in the West. This paper investigated the trends of social media research in Malaysia from 2004 to 2015. A quantitative content analysis was conducted on 79 articles in 21 selected academic journals in identifying the methodological approach, theoretical application, topical, social media type, type of content and research developmental phases of social media scholarship. Findings revealed social media research in Malaysia is still in formative stage but increasing throughout the years. Unlike findings from past analyses, theory-driven articles in Malaysia were more prevalent than theoretical presence in the West. Nonetheless, Malaysian scholars still lack in conceptualisation and expansion of theories. The study suggests for a more explicit theoretical foundation and technology advancement in the future research. This study also suggests that future scholarly endeavours should have better methodological rigour and wider dispersion of social media medium and content type

Lean manufacturing best practices in SMEs

Last two decades had witnessed explosion of researches into the area of manufacturing improvement such as lean manufacturing, total quality management, total productive maintenance and their application within various manufacturing companies such as automotives, electronics, plastics components and etc.It was proven that lean manufacturing was considered as the best manufacturing system in the 21st century.A comprehensive literature review was conducted to get necessary lean information.The review is focused on SME definitions and characteristics.This is followed by reviewing the lean practices and discusses them based on SMEs’ capabilities. The aim of this paper is to present feasible lean practices for lean implementation in SMEs.There are seventeen lean practices which could be considered are feasible and relevant to the SME characteristics.The proposed practices were based on three categories; least investment, feasible to apply in SME and recommended by researcher

Parental attachment and cyberbullying experiences among Malaysian children

The purpose of this article is to illustrate the links between the three factors of parental attachment (i.e., communication, trust, and alienation) and cyberbullying experiences among school-going children. A total of 375 students aged 9 to 16 years old were selected using stratified sampling method from 8 schools in Selangor. The authors adapted a 10-item instrument from the previous studies of Youth Internet Safety Survey (YISS) and EUkidsonline scales to assess the cyberbullying prevalence based on two sub-dimensions (online harassment and sex-based bullying). The confirmatory factor analysis (CFA) was used to analyse the construct validity of the scales. Structural equation modelling (SEM) then was used to test the study hypotheses. The final model has an estimated that 10% (R2=.95) of the variance in cyberbullying is explained by parental attachment, indicating only the alienation factor predicted the children’s cyberbullying experiences. The findings, however, supported a differentiated approach to positive parenting

NOTE ON THE DISTRIBUTION OF PTEROSPERMUM PECTENIFORME KOSTERM. (DOMBEYOIDEAE : MALVACEAE S .L.) IN PENINSULAR MALAYSIA

The rare species Pterospermum pecteniforme previously is only known from two herbarium collections in the late 1960 and early 1970 in Perlis and Kedah (Langkawi Islands; Pulau Timun), respectively. In this paper, we have added two additional localities from two islands of Langkawi Archipelago namely, Pulau Dayang Bunting and Pulau Singa Besar. This species is locally quite common on both islands. All fertile collections of this species are only from the fruits while the flower is still unknown

Establishment of Wolbachia strain wAlbB in Malaysian populations of Aedes aegypti for dengue control

Dengue has enormous health impacts globally. A novel approach to decrease dengue incidence involves the introduction of Wolbachia endosymbionts that block dengue virus transmission into populations of the primary vector mosquito, Aedes aegypti. The wMel Wolbachia strain has previously been trialed in open releases of Ae. aegypti; however, the wAlbB strain has been shown to maintain higher density than wMel at high larval rearing temperatures. Releases of Ae. aegypti mosquitoes carrying wAlbB were carried out in 6 diverse sites in greater Kuala Lumpur, Malaysia, with high endemic dengue transmission. The strain was successfully established and maintained at very high population frequency at some sites or persisted with additional releases following fluctuations at other sites. Based on passive case monitoring, reduced human dengue incidence was observed in the release sites when compared to control sites. The wAlbB strain of Wolbachia provides a promising option as a tool for dengue control, particularly in very hot climates

Spatial distribution and long-term persistence of Wolbachia-infected Aedes aegypti in the Mentari Court, Malaysia

Dengue is endemic in Malaysia, and vector control strategies are vital to reduce dengue transmission. The Wolbachia strain wAlbB carried by both sexes of Ae. aegypti was released in Mentari Court, a high-rise residential site, in October 2017 and stopped after 20 weeks. Wolbachia frequencies are still being monitored at multiple traps across this site, providing an opportunity to examine the spatiotemporal distribution of Wolbachia and mosquito density with respect to year, residential block, and floor, using spatial interpolation in ArcGIS, GLMs, and contingency analyses. In just 12 weeks, Wolbachia-infected mosquitoes were established right across the Mentari Court site with an overall infection frequency of >90%. To date, the Wolbachia frequency of Ae. aegypti has remained high in all areas across the site despite releases finishing four years ago. Nevertheless, the Wolbachia invaded more rapidly in some residential blocks than others, and also showed a relatively higher frequency on the eighth floor. The Ae. aegypti index tended to differ somewhat between residential blocks, whilst the Ae. albopictus index was relatively higher at the top and bottom floors of buildings. In Mentari Court, only a short release period was required to infiltrate Wolbachia completely and stably into the natural population. The results inform future releases in comparable sites in a dengue control programme

Value stream mapping – a tool to detect and reduce waste for a lean manufacturing system

Waste is a non-value added activity that may exist everywhere in the production line. This waste is an activity that consumes resources but does not directly contribute to product or service and does not add value to the customer. This paper presents the classification of waste and the steps to implement value stream mapping (VSM) which is one of the powerful lean practice to detect and analyze waste activities in the manufacturing operation

Case Studies on the Implementation of Lean Manufacturing in the Automotive Malaysian Companies

Lean manufacturing is one of the initiatives that many major businesses in the world have been trying to adopt in order to remain competitive in an increasingly global market. The focus of the approach is on cost reduction by eliminating non-value added activities. Originating from the Toyota Production System, many of the tools and techniques of lean manufacturing have been widely used in discrete manufacturing. The purpose of this study is to investigate the approach of adopting lean, the tools and techniques implemented, the changes in the organizations, the problems encountered as well as the lessons learnt. This paper describes the results and findings of four industrial case studies conducted in different electrical and electronics companies in Malaysia. Interviews were conducted with the key personnel to answer some issues which were crucial in this study. Comparisons and discussion were made among the case companies. One of the key findings obtained is that people in the organization should take the lean mind-set and act in the lean way in order to make a lean initiative successful. The application of kaizen and 7 quality control tools are most popular implementation in the selected case study companies as the tools to eliminate non-value added activities