This study focuses on the application of the Malaysian Driving Behaviour Questionnaire(DBQ). The aim of this study is
to investigate and analyse the significant driving behaviour of the ageing Malaysian automobile drivers. The sets of
questionnaire was completed by a total number of 102 ageing drivers consists of 58 males (56.86%) and 44 females
(43.14%). The age of respondents ranges from 50 to 75 years (M = 57.21) and (SD = 5.60). The DBQ contains 12 items
of demographic questions and 41 items measuring driving behaviour in traffic. The driving behaviours were classified
into four factors which are driving distractions, violations, errors and lapses. The most significant correlation
coefficient is between age and distractions (r = 0.456, p
Extensive research has been carried out over the years to determine the maximum acceptable weight that a worker is capable of lifting in a given situation among the Occidental populations in the Europe and US. At present, there is a scarcity of studies in which lifting frequency is used as the measuring variable, especially in developing countries such as Malaysia. Therefore, the objective of this study is to determine the effects of lifting loads on the maximum acceptable frequency limit (MAFL), physiological response (muscle activity) and rating of perceived exertion (RPE) for asymmetric lifting and lowering tasks of Malaysian males.Ten male subjects are recruited in this study and they perform asymmetric lifting and lowering tasks repetitively for 30 minutes. Two lifting loads are considered (1) 1 kg and (2) 5 kg. Each of the subjects adjusts his frequency of lifting using a psychophysical approach. The subjects are instructed to perform the lifting and lowering task as fast as they could over duration of 30 minutes without exhausting themselves or becoming overheated. Electromyography (EMG) signals are recorded from four muscles (Right Erector Spinae (RES), Left Erector Spinae (LES), Right Trapezius p Descendenz (RTD) and Left Trapezius p Descendenz (LTD) and analysed in terms of the normalized MVC during asymmetric lifting and lowering tasks. The ratings of perceived exertion (RPE) for four body parts (arms, lower back, shoulders and entire body) are also collected after the subjects have completed the lifting and lowering task. The mean frequency of the lifting and lowering task obtained from the experiment is 13.41 and 9.66 times/minute for a lifting load of 1 and 5 kg, respectively. The results of the independent sample t-test show that load has a statistically significant effect on the maximum acceptable frequency limit (p < 0.05). However, it is found that even though there is an increase in muscle activity and RPE with an increase in lifting load, there is no significant difference in the overall mean muscle activity and RPE (p > 0.05). The percentage decrease in the maximum acceptable frequency for Malaysian males is higher than the Occidental populations for both of the loads investigated in this study.
A survey was conducted to investigate the relationship between job satisfaction and job factors that affect work design in two automotives manufacturing companies in Malaysia. A set of multiple choices questionnaires was developed and data were collected by interviewing the employees at the production plant. Hundred and seventy male subjects between the ages of 18 to 40 years with the mean age of 26.8 and SD of 5.3 years and mean work experience of 6.5 and SD of 4.9 years took part in the survey. The survey focused on job factors, i.e. skill variety, task identity, task significance, autonomy and feedback. The results support the previous findings that job factors are significantly correlated to job satisfaction. Furthermore, it also highlights the significant influence of age, work experience and marital status.
It is known that lifting tasks are one of the risk factors of musculoskeletal disorders in the automotive industry.
Extensive research has been carried out over the years to develop guidelines and determine safe limits in which an
individual can lift. For this reason, the objective of this study is to determine the significant risk factors of
musculoskeletal discomfort among manual lifting task workers in the automotive industry, and propose a
methodological framework for future research on manual lifting tasks. The subjects of this study comprise 211
manual material handling workers from the automotive industry. The subjects completed a set of questionnaires
which are used to elicit information on their demographic characteristics, as well as physical factors and the
prevalence of musculoskeletal discomfort. The Chi-Square test was used to determine the relationship between the
risk factors and musculoskeletal discomfort. The findings of the study show that the following postures (trunk bent
slightly forwards, hands above the knee level (p < 0.05), trunk twisted (over 45o) and bent sideways (p < 0.05) are
the significant risk factors of musculoskeletal discomfort among manual lifting task workers in the automotive
industry. A methodological framework on manual lifting task in the automotive industry is proposed based on the
findings of this study. The framework is developed based on the need to model human lifting capabilities so that task
demands can be designed to fit the workers’ capacity when performing lifting tasks.
Most studies have examined the association of ergonomic risk factors and musculoskeletal discomfort in developed countries. Meanwhile the data are still lacking in developing countries such as Malaysia. The aim of this study was to determine the relation between risk factors and musculoskeletal discomfort among manual material handling workers in Malaysian automotive industries. A total of211 manual material handling workers from automotive industries completed a set of questionnaire on the individual, physical and environmental factors and the prevalence of musculoskeletal discomfort. The Chi-Square test and logistics regression analysis were used to determine the relationship of the risk factors and musculoskeletal. The findings highlighted that job tenure was significantly correlated with musculoskeletal discomfort among the workers (OR=2.33-5.56). The most significant physical risk factor that was associated with musculoskeletal discomfort was bending the trunk forward slightly, hands above knee level, which was significantly related to lower back discomfort (OR=5.13, 95%CI=1.56-16.8), thigh discomfort (OR=5.1, 95%CI=1.01-25.53) and wrist discomfort (OR=3.65, 95%CI=1.06-12.53). Twisting of the trunk (over 45o) and bending sideways were significantly associated to lower back discomfort (OR=4.04, 95%CI=1.44-14.44), and thigh discomfort (OR=4.3, 95%CI=1.29-8.50). The findings also highlighted that environmental factors was associated with musculoskeletal discomfort (p < 0.05. Musculoskeletal discomfort can be reduced by lowering work-related risk factors among automotive manual material handling workers, particularly by focusing on significant factors, including job tenure, bending or twisting postures and environmental factors.
It was suggested by most researchers that train drivers’ workload and alertness levels attribute to train accidents. The main objective of this study is to determine the significant patterns of mental workload and alertness levels of train drivers with respect to the conditions. The data are collected from simulation experiments on 15 professional train drivers. The simulation experiments are performed under three driving conditions (i.e. daytime, rainy daytime and rainy night) using a train driving simulator set. Electroencephalogram (EEG) signals are collected from six significant points on the body of the subjects. It is found that the mental workload of the train drivers tends to be high during rainy night driving condition and sleepiness occurs which is indicative of low vigilance. The beta amplitude increases under rainy night driving condition which may be attributed to viewing difficulties while driving in the dark. The results reveal that there is a significant different between each session (p = 0.042) especially with the pattern for rainy night driving. It is also observed that there is lower mental workload among the train drivers, which indicates that the train drivers are detached from their work.
Elderly are exposed to physical impairment. This has a strong impact on their daily activities including
frying, which is one of the most popular cuisine preparations. The stove height and work envelope
are two major ergonomic issues in performing cooking task. There has been little research focusing
on Malaysian elderly task performing in addressing these issues. The objectives of this study were to
identify the acceptable stove height and depth and to determine the working envelope among Malaysian
elderly using anthropometric data. A total of 55 Malaysian elderly (25 male and 30 female) aged between
60 to 85 years participated in this study. Five body measurements were taken from each subject using
an anthropometer. The measurements are stature height, shoulder height, arm span, arm reach forward
and waist height. Apart from these anthropometric measurements, their present stove height was also
measured. The acquisition of stove height dimensions was performed through a series of door to door
visit of the elderly homes in Kg. Sg. Merab. These variables were used to estimate the elderly working
envelope and determine the stove height, width and depth. Data were analysed using SPSS software. The
waist height dimension was to estimate the stove height, the arm reach forward for the depth and the arm
span for the length of the table-top where the stove was placed. Meanwhile the stature and shoulder height
were used for estimating the position of the overhead compartment or placement of cooking utensils.
The 5
th
percentile was chosen since it is appropriate to accommodate 90% of the studied population. The 5
th
percentile was also applied for the setting
of the working envelope so as to provide better
reaching tolerances. Meanwhile, standard was used
to compare the present state of the studied kitchen
setting. The results show that 56.4% of the elderly
waist height is lower than the standard table-top
height which is 36 inches (91.4cm) and 36.4% of the stove height was found higher than that of the standard. This could apparently cause fatigue and
discomfort to shoulders, the neck, the arm and the back of the user. Anthropometrics measurements can
be used for estimating the stove height, length and depth. These could also calculate a space taken for
certain physical activities, such as frying task envelope. Providing a good combination of stove height,
length, depth and ergonomic working envelope could hopefully improve the elderly cooking task and
increase their quality of life.
A methodology was developed for diagnosing industrial work, which includes questionnaire, observation, measurements, data collection and statistical analysis. A survey was conducted to investigate the relationship between job satisfaction and factors that affect work design in 2 automotives manufacturing companies in Malaysia. A basic work design model was proposed. The aim of this model was to determine the factors that influence employees' perception towards their work. A set of multiple-choice questionnaires was developed and data was collected by interviewing employees at a production plant. The survey focused on job and environmental factors. The results supported the proposed model and showed that job and environmental factors were significantly related to job satisfaction. They highlighted the significant influence of age, work experience and marital status on job satisfaction. Further, environmental factors, especially the surroundings, context dependence and the building's function, also had a significant impact on job satisfaction.
A methodology is developed in diagnosing the effect of job organizational factors on job satisfaction in two automotive industries in Malaysia. One hundred and seventy male subjects of age 18-40 years with the mean age of 26.8 and standard deviation (SD) of 5.3 years and the mean work experience of 6.5 years and SD of 4.9 years took part in the study. Five job organizational factors were tested in the study including job rotation, work method, training, problem solving and goal setting. A job organization questionnaire was designed and was based on respondents' perception in relation to job satisfaction. The results showed that job organization factors were significantly related to job satisfaction. Job rotation, work method, training and goal setting showed strong correlation with job satisfaction while problem solving had intermediate correlation in the first automotive industry. On the other hand, most job organization factors showed intermediate correlation with job satisfaction in the second automotive industry except the training factor which had low correlation with job satisfaction. These results highlight that job rotation, work methods, problem solving and goal setting are outstanding factors in the study of job satisfaction for automotive industries.
A new multiobjective dynamic fuzzy genetic algorithm is applied to solve a fuzzy mixed-model assembly line sequencing problem in which the primary goals are to minimize the total make-span and minimize the setup number simultaneously. Trapezoidal fuzzy numbers are implemented for variables such as operation and travelling time in order to generate results with higher accuracy and representative of real-case data. An improved genetic algorithm called fuzzy adaptive genetic algorithm (FAGA) is proposed in order to solve this optimization model. In establishing the FAGA, five dynamic fuzzy parameter controllers are devised in which fuzzy expert experience controller (FEEC) is integrated with automatic learning dynamic fuzzy controller (ALDFC) technique. The enhanced algorithm dynamically adjusts the population size, number of generations, tournament candidate, crossover rate, and mutation rate compared with using fixed control parameters. The main idea is to improve the performance and effectiveness of existing GAs by dynamic adjustment and control of the five parameters. Verification and validation of the dynamic fuzzy GA are carried out by developing test-beds and testing using a multiobjective fuzzy mixed production assembly line sequencing optimization problem. The simulation results highlight that the performance and efficacy of the proposed novel optimization algorithm are more efficient than the performance of the standard genetic algorithm in mixed assembly line sequencing model.
A study was conducted to investigate the effects of repetitive light tasks of low and high precision on upper limb muscles and brain activities. Surface electromyography (EMG) and electroencephalography (EEG) were used to measure the muscle and brain activity of 10 subjects. The results show that the root-mean-square (RMS) and mean power frquency (MPF) of the muscle activity and the mean power of the EEG alpha bands were higher on the high-precision task than on the low-precision one. There was also a high and significant correlation between upper limb muscle and brain activity during the tasks. The longer the time and the more precise the task, the more the subjects become fatigued both physically and mentally. Thus, these results could be potentially useful in managing fatigue, especially fatique related to muscle and mental workload.
The status of thrombophilia in Asian women with recurrent pregnancy loss (RPL) is obscure and poorly understood. Numerous studies suggest the non-existence or extreme rarity of the two important thrombophilia markers, factor V Leiden (FVL) and prothrombin G20210A (PTG) mutations, in patients of Asian ancestries. Thus, the consensus that thrombophilia is rare among Asians and laboratory investigations is irrelevant. We therefore investigated Malaysian women with RPL for thrombophilia abnormalities.
OBJECTIVE:
To evaluate the 50-g glucose challenge test (GCT) on pregnancy outcome in a multiethnic Asian population at high risk for gestational diabetes (GDM).
METHODS:
GCT was positive if the 1-hour plasma glucose level was >or=7.2 mmol/L. GDM was diagnosed by a 75-g glucose tolerance test using WHO (1999) criteria. Of the 1368 women enrolled in the study, 892 were GCT negative, 308 were GCT false-positive, and 168 had GDM. Pregnancy outcomes were extracted from hospital records. Multivariable logistic regression analysis was performed with GCT negative women as the reference group.
RESULTS:
GCT false-positive status was associated with preterm birth (adjusted odds ratio [AOR] 2.1; 95% CI, 1.2-3.7) and postpartum hemorrhage (AOR 1.7; 95% CI, 1.0-2.7). GDM was associated with labor induction (AOR 5.0; 95% CI, 3.3-7.5), cesarean delivery (AOR 2.2; 95% CI, 1.6-3.2), postpartum hemorrhage (AOR 2.1; 95% CI, 1.2-3.7), and neonatal macrosomia (AOR 2.5; 95% CI, 1.0-6.0).
CONCLUSION:
GCT false-positive women had an increased likelihood of an adverse pregnancy outcome. The role and threshold of the GCT needs re-evaluation.
To evaluate the influences of mode of immediate preceding delivery and number of prior vaginal births on the risk of repeat cesarean and neonatal admission at attempted vaginal birth after cesarean.
This study was conducted to develop muscle and mental activities on repetitive precision tasks. A laboratory experiment was used to address the objectives. Surface electromyography was used to measure muscle activities from eight upper limb muscles, while electroencephalography recorded mental activities from six channels. Fourteen university students participated in the study. The results show that muscle and mental activities increase for all tasks, indicating the occurrence of muscle and mental fatigue. A linear relationship between muscle activity, mental activity and time was found while subjects were performing the task. Thus, models were developed using those variables. The models were found valid after validation using other students' and workers' data. Findings from this study can contribute as a reference for future studies investigating muscle and mental activity and can be applied in industry as guidelines to manage muscle and mental fatigue, especially to manage job schedules and rotation.