13 research outputs found
Development of Al-Cu-SiCp metal matrix composite for automotive applications
In recent years, the demand for reduced weight and high performance materials
for automotive applications such as brake disc have increased. The newly developed,
aluminium metal matrix composite (AI-MMC) reinforced with silicon carbide (SiC)
particulate seem suitable to be an alternative material for this application. In this
experimental study, AI-Cu-SiCp MMC was developed through stir casting method with
sand mould. A constant 4.5% of weight percentage of 5 !-Ull pure copper powder was
added to the mixtures to enhance the properties of AI-MMC. The effects of particle
sizes of SiC as well as the weight percentage of SiC, pouring temperature and stirring
time on the hardness, wear, compressive properties, flexure behavior and density of Al�Cu-SiCp MMC were investigated. Taguchi's Robust Parametric Design was used \vith
ilmer array L9 34 and outer array with 2 replications to plan the experimental runs. A
statistical Pareto Analysis of Variance (Pareto ANOVA) was employed to detennine the
significant factors of these properties and optimum combinations of process variables
for targeted functions. From the analysis, it was found that particle sizes of SiC is the
most significant factor for density characteristic and compressive properties while
weight percentage of SiC is the most significant factor for hardness and wear resistance
characteristics. Optimum combinations were determined and conformity test were
conducted to verify the optimum properties of newly developed material, AI-Cu-SiCp
MMC. Optimum combination of hardness was AIB2CoDO ( 59 fllll particle size af SiC,
15% af weight percentage af SiC, 675°C pauring temperature and 5 minutes stirring
time) with 82.5 HV; wear rate A2B2C2Do ( 106 flm particle size af SiC, 15% af weight
percentage af SiC, 725°C pauring temperature and 5 lllinutes stirring time) with 1.585
x 10-5 g/sec; compressive strength A1B2C2Dl (59 flm particle size of SiC, 15% afweight
percentage af SiC, 725°C pouring temperature and 10 minutes stirring time) with
9410.06 MPa and density AoB1C1Dl ( 40 flm particle size af SiC, 10% af weight
percentage of SiC, 700°C pauring temperature and 10 minutes stirring time) with
2.6592 g/cm3
Assessment of BioPattern in Novel Idea Generation for Bio-Inspired Design
BioPattern is a novel ideation tool for Bio-Inspired Design, built based on TRIZ, SAPPhIRE, and pattern language. It consists of an ontology, known as pattern-based ontology, and a sustainability evaluation, known as Ideal Windows. However, this framework has not been tested yet. Therefore, this article is to present the results and analysis of the case study conducted to assess this biomimicry framework. Two different groups of students, Creative & Innovation class (controlled group) and Integrated Engineering Design class (experimental group), are asked to generate innovative ideas where the experimental group employed BioPattern as the ideation tool. It is found that the level of innovation for the inventive ideas generated by the experimental group is much higher compared to that of the controlled group. Based on the inventive ideas produced by the experimental group, BioPattern is found to be efficient in ideation, able to generate effective solution, the problem-solution pairs of the ontology are adequate, and the biological solutions suggested are transferable as technological solutions. It can be concluded that BioPattern is able to bridge the biology-engineering gap
Development of Distraction Risk Index (DRI) Among the Intrastate Bus Driver in Kuala Lumpur, Malaysia
Bus services is one of the main public transport chosen by the people all around the world especially in the big city such as Kuala Lumpur. However, the safety of the passenger of the bus services become main concern among the researchers due to increasing number of accidents among the bus services. Some researcher found that, the major factor of the accidents involving bus services was caused by the bus driver distraction. Therefore, the objective of this research is to develop the Distraction Risk Index (DRI) among the intrastate bus driver. This research will only focus on the intrastate bus driver in Kuala Lumpur. Survey which adapting the Hampton University Transportation Centre Bus Driver Distraction Survey was used and distributed to 215 intrastate bus drivers in Kuala Lumpur, Malaysia. It was found that there were four sources of distraction which classified as very high risk which were condition of the bus, traffic congestion, drivers’ welfare and drivers’ health. Findings of this research can be used as a platform for future improvement for the performance of the intrastate bus services. This research also can provide assistance to future researchers to design and provide solution to overcome sources of distraction
Evaluation of whole body vibration and back pain problem among Light Rapid Transit (LRT) drivers
A cross sectional study was conducted to evaluate whole body vibration (WBV) and back pain problem among light rail transit (LRT) driver. This study was carried out to determine exposure level of whole body vibration and identify back pain problem due to whole body vibration exposure among LRT driver. Standardized Nordic questionnaire was used for the analysis of musculoskeletal symptoms, to identify the prevalence of back pain, information about health history, working time duration, and working experiences was obtained from 52 drivers of light rail transit (LRT) train. HVM 100 Larson Davis was used to measure whole body vibration measurement of eight LRTs with different vehicle number. The measurement of whole body vibration was done during operation working time. The data collected from HVM 100 were transferred to the Blaze software for getting the vibration magnitude of the experiment while data collected from survey were analyzed by using Statistical Package for the Social Sciences (SPSS) for statistical analysis. The analysis of graph patterns and the differentiation of magnitude value from each LRT were studied to determine the exposure level of vibration. A high prevalence of back pain (82.7%) among LRT drivers was found and high daily exposure level was obtained. The finding showed that, there are relations between back pain and daily vibration exposure which resulted in a correlation coefficient of 0.709, with significant at α = 0.05. In conclusion, it was expected that the individuals subjected to the high vibration levels would tend to report back pain
Physical fatigue assessment for intrastate bus driver
Fatigue is considered a psychological or mental fatigue type characterized by subjective feelings of a disinclination to continue driving, drowsiness, fatigue, and deduction motivation. Bus drivers in Malaysia have been facing physical fatigue from driving for many years. Therefore, investigating the psychophysiological factor that related to fatigue could improve understanding and management for fatigue in the transport industry. Physical factors are divided by two parts that is upper and lower body. The objective of this study is to identify the cause, determine the level and analyze the physical fatigue on bus driver. There were two methods applied in this study, which were Modified Nordic Questionnaires that represent subjective measurement and surface Electromyography (sEMG) the objective measurement. Results from sEMG showed neck and upper back muscle groups leads to fatigue as the muscle is running out of energy based from the graph. Through the sEMG data, it can determine the level of physical fatigue on bus driver and analyzed the physical fatigue. Findings of this study from the questionnaire data analysis using the Statistical Package Social Science software, it is proved that physical fatigue really occurred to the intrastate bus driver. Results also showed significant correlation relationship between physical and mental
Development of an integrated train driver performance model / Mohd Azlis Sani Md Jalil
The purpose of this study was to develop an integrated performance model of train drivers. A human performance measure was developed, integrating several significant factors of the train driver, and a theoretical framework specified for train driver was established from an extensive review of the literatures. This framework formed the foundation of the study in order to understand the significant factors influencing the performance of a train driver. Three main domains of human, activity and context were proposed to represent the key indicators of the train driver's performance.
The evaluation was conducted on train drivers of a major train operating company (TOC) in Malaysia, focusing only on drivers of intercity passenger trains and freight trains. 229 respondents had participated in the quantitative paper-and-pencil survey conducted, and the data obtained was subsequently analysed using SPSS software. An integrated framework was then tested using structural equation modelling (SEM)-PLS approach in theSmartPLS software to determine the relationship among the significant factors of train driver performance. Fourteen factors were hypothesized and tested under the three main domains, namely fatigue, job related tension (internal and external conflict), job satisfactions, occupational stress and sleepiness, which were grouped under human domain; while driving task and job demand represented the activity domain; and lastly, the context domain consisted of the working condition, safety culture, safety issue, working environment and work facilities.
The results indicated that fatigue, job related tension (internal conflict) and occupational stress; under human domain were found to be the significant factors which influence the performance of train drivers. For the activity domain, hypothesis testing proved that driving task, was significant factor. In the context domain; three factors were found to be significant. These include safety culture, working environment and
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working condition. To summarize, the study identified a total of seven significant factorswhich include occupational stress, job related tension – internal conflict, fatigue, driving task, work environment, safety culture and working condition. However, the results have failed to support the remaining seven factors of job related tension (external conflict), job satisfactions, sleep, job demand, work facilities, and safety issue.
Significant to this research was that an integrated Malaysian train driver performance model has been successfully developed for identifying the significant factors that influence train driver performance, highlighting the interaction between human factors, human activities and its context. Through this approach, this study has looked at the significant factors in holistic and comprehensive perspective without ignoring other potential domains of factors. Therefore, this model would benefit the rail industry by assisting them in identifying the factor(s) That require close observation and improvement. Thus, the overall performance of the industry would be upgraded and contributes to the betterment of the system and the rail industry
Human performance in transportation a comparative study of human performance models
Human performance model (HPM) is an attempt to integrate and study the factors, and aspects influence the performance of a human during performing a job. Unfortunately, human factors and performance were left behind and be considered as independent factors with very fewer contributions to the system performance. The understanding of human performance will enable the analysis of potentially conflicting task demands in organized and structured ways as the earliest stages in a design. This paper is to address the importance of human performance to be considered in the transportation industry. Three keys human performance models were reviewed and presented for better understanding and to compare various factors influences the performance of a human
Sleepiness among train drivers: a case study in Malaysia
To ensure system performance and safety, train drivers need to be highly efficient. It has always been given the highest priority by all stakeholders in railway industry. Awareness and better understanding on the importance of human performance towards productivity and efficiency have increased. Monotonous driving is one of the major contributing factors for sleepiness among train drivers. The objective of the study is to determine the prevalence of sleepiness among train drivers and the importance to address sleepiness problem by the train operating companies (TOC) in Malaysia. 195 male train drivers were selected to answer self- administrated questionnaire to gather information on age and working experience. The Epworth Sleepiness Scale (ESS) was used to measure sleepiness among the train drivers; where the respondents themselves rate their chances to doze off or fall asleep in eight typically different situations. Flinders Fatigue Scale (FFS) was used to measure fatigue among the train drivers. The respondents were locomotive drivers and junior drivers from five different depots across Peninsular Malaysia; who drive locomotives in long haul operations. The results of the analysis are presented to provide better understanding on the sleep-related factors the impact on the performance of train drivers
Prevalence and impact of work-related musculoskeletal disorders among food delivery riders in Eastern Peninsular Malaysia
Work-related Musculoskeletal Disorders (WMSDs) are currently a matter of concern in the occupational world, where it is the leading cause of disability among workers. Food delivery riders were among the neglected workers even though they were highly exposed to the WMSDs. Thus, this study aims to quantify the magnitude of WMSDs among the riders and the impact on their work. This was a cross-sectional study involving 191 food delivery riders in Eastern Peninsular Malaysia. The Standardized Nordic Musculoskeletal Questionnaire (M-SNMQ), which was self-administered and validated for Malay translation, was used to quantify the prevalence of WMSDS based on various specific body regions. WMSD prevalence over a 12-month period was 74.9%. Upper back pain (UBP) (55.6%) and lower back pain (LBP) (73.3%) were the two most common body regions to experience WMSD symptoms. The least-complained body regions were thighs and feet, with a prevalence of 2.6% and 3.1%, respectively. The affected body regions that caused the highest daily life disturbance were the shoulders and knees, while those with shoulders symptom were more likely to be absent from work. Finally, LBP was the highest body region with at least a moderate pain score. In general, the findings should be a matter of concern among health authorities and others to improve the quality of life among the riders. To lower the prevalence of WMSDs among this understudied group, additional interventional research should be built on the findings of this study
Understanding Factors of Distraction among Intrastate Bus Driver
The increase in number of the world population have affected the demand for public transport especially in larger cities. Intrastate buses are chosen as the main public transport by many people due to its affordable fares. Therefore, a better performance of the intrastate bus drivers would be significant to cater the high demand. Nevertheless, distraction among the intrastate bus drivers have been found as one of the major factors that could affect the performance of the drivers. Therefore, the objective of this paper is to provide a better understanding on the factors of distraction among intrastate bus drivers. This paper refers to findings from previous researches which are related to this field of study. In conclusion, this paper will provide a list of factors of distraction among the intrastate bus drivers which may degrade their performance