22 research outputs found
Influence of midblock U-turn facility on traffic flow reduction and its effect on kinematic wave propagation
Midblock median opening facilities are constructed on multilane highways in Malaysia solely for the purpose of facilitating U-turn movements along federal road segments. In Malaysia, a persistence problem of traffic conflicts and congestion at multi-lane highway intersections forced the federal authorities to invest in midblock median opening facilities as traffic conflict reduction mechanism. Although the authorities have succeeded in reducing traffic conflicts at intersections, the realisation of maximum traffic flow at the midblock zone is in doubt. The aim of the study is to determine influence of midblock U-turn facility on traffic flow reduction and its effect on kinematic wave propagation. The objectives are to determine traffic volume, speeds as well as vehicle types at the midblock and free-flow zones for both directional flows. As well as examine the effect of traffic flow reduction on kinematic wave propagation. It was assumed that traffic density was a resultant of speed and traffic flow hence not directly affected by midblock zone. It implies that traffic flow reduction was fully the result of speed changes. Where traffic flow reduction has occurred, the ensuing kinematic wave propagation would be investigated in order to determine whether it is a rarefaction wave or traffic shockwave. Vehicle types, traffic volumes and vehicles speeds were collected using automatic traffic counters at each directional flow of the four surveyed sites for six months. The survey data were collated and analysed. Passenger car equivalent values were modified and used to convert traffic volume to flow. Results show that midblock facility would cause about 4 per cent reduction in traffic flow at the diverging section and 10 per cent reduction in traffic at the merging section. The findings give traffic capacity values under different scenarios and can be incorporated into a wider strategy for dynamic traffic management. Findings from kinematic wave propagations confirm that midblock facility would cause traffic shock wave at the merging not the diverging section. Estimated traffic flow reduction from the study can be used as evidence to highlight the need to redesign midblock facility in Malaysia. One possible solution among others is to incorporate appropriate acceleration lane at the merging section thereby minimising the potential for vehicle collision. The study concluded that midblock facility will cause traffic significant flow reduction
Comparison between the Use of LMA™ and SLIPA™ in Patients Undergoing Minor Surgeries.
Supraglottic airway devices have been used as safe alternatives to endotracheal intubation in appropriate types of surgery. This was a prospective, randomised, single blind study comparing the use of LMA™ and SLIPA™ in terms of ease of insertion, haemodynamic changes and occurrence of adverse effects (e.g. blood stains on the device upon removal and sore throat). A total of 62 ASA I or II patients, aged between 18 to 70 years were recruited for this study. Patients were randomised into two groups; LMA™ and SLIPA™ group. Following induction of anaesthesia, an appropriate sized LMA™ or SLIPA™ was inserted after ensuring adequate depth of anaesthesia. Anaesthesia was maintained with oxygen, nitrous oxide and sevoflurane. The ease of insertion was graded and haemodynamic changes were recorded at 2 minute intervals up to 10 minutes after insertion of the airway devices. The presence of blood stains upon airway device removal at the end of surgery and incidence of sore throat was also recorded. No difficult insertion was experienced in either of these devices. Insertion was either easy [LMA™ 87.1% versus SLIPA™ 80.6% (p = 0.49)] or moderate [LMA™ 12.9% versus SLIPA™ 19.4% (p = 0.16)]. Throughout the study period, the haemodynamic changes that occurred in both groups were not statistically different. Traces of blood were noted on the surface of the device in 9.7% of patients in the SLIPA™ group versus 6.5% of patients in the LMA™ group. The incidence of sore throat was recorded in 12.9% versus 19.4% of patients in the SLIPA™ and the LMA™ groups respectively. These findings were not statistically significant. In conclusion, this study showed no significant differences between the use of LMA™ and SLIPA™ in terms of ease of insertion, haemodynamic changes and adverse effects in patients undergoing minor surgical procedures
Optimization of biohydrogen production by Clostridium butyricum EB6 from palm oil mill effluent using response surface methodology
Clostridium butyricum EB6 successfully produced hydrogen gas from palm oil mill effluent (POME). In this study, central composite design and response surface methodology were applied to determine the optimum conditions for hydrogen production (Pc) and maximum hydrogen production rate (Rmax) from POME. Experimental results showed that the pH, temperature and chemical oxygen demand (COD) of POME affected both the hydrogen production and production rate, both individually and interactively. The optimum conditions for hydrogen production (Pc) were pH 5.69, 36degreeC, and 92g COD/l; with an estimated Pc value of 306ml H2/g carbohydrate. The optimum conditions for maximum hydrogen production rate (Rmax) were pH 6.52, 41degreeC and 60g COD/l; with an estimated Rmax value of 914ml H2/h. An overlay study was performed to obtain an overall model optimization. The optimized conditions for the overall model were pH 6.05, 36degreeC and 94g COD/l. The hydrogen content in the biogas produced ranged from 60% to 75%
Analysis of Road Traffic Crashes Data of Perak State in Malaysia
Road traffic accidents are one of Malaysia's top five major causes of death and is one of the most critical public health concerns in 2023. As a result, this article offers research based on data from different Malaysian government organisations and analysing the changes in the pattern of Road Traffic Crashes (RTC) in Perak, Malaysia. From 2011 to 2018, data was analysed based on road traffic collisions and categories of casualties concerning gender, age, types of roads and vehicles, and road users. The mortality and injury rates per 100,000 people were used to calculate performance for road safety. It was found that with a 0.59% increase in Perak's population and an increase in the number of cars, there are 30,669 total crashes and 491 road deaths in 2020. Furthermore, this study discovered that motorcycles were the most common vehicle involved in road traffic deaths from 2011 to 2018, which should raise concerns since motorbikes have become an essential mode of transportation. In Perak, most road deaths were males between the ages of 16 and 20. Finally, this study discovered that the death and injury rates per 100,000 people in Perak are 19.56 and 75.82, respectively, indicating that the fatality rate is dropping, but the injury rate increased dramatically in 2020 compared to 2019. The Perak state administration must investigate why the situation has worsen after a decade. Somehow or rather, the state must address this issue, and it is advised that further research be conducted to identify mechanisms to enhance the current scenario to lower the number of RTCs, notably deaths, in the state
Assessment of Young Drivers' Driving Behaviour and Driving Speed Along Horizontal and Vertical Alignments
Young drivers are more likely to experience car crashes as they tend to have risky driving behaviours. This study aims to assess young drivers' driving behaviour and driving speed along the horizontal and vertical alignments of roads. The 20 young drivers who participated in this study were asked to complete a self-reported assessment (Driver Behaviour Questionnaire) and then invited for an on-road driving assessment during daytime and night-time, along horizontal and vertical road alignments at a selected route in Skudai, Johor. The results from the Driver Behaviour Questionnaire revealed that distractions during driving was the most frequently reported behaviour that caused car crashes amongst young drivers, followed by error and violation. Speed profile was found to be higher during daytime when compared to night-time. A significant difference in speed between male and female drivers was noted at horizontal curves during daytime and vertical curves during night-time. The study concluded that such aberrant driving behaviours would have an impact on the driving performance, particularly on horizontal and vertical curves
Effects of pH, glucose and iron sulfate concentration on the yield of biohydrogen by Clostridium butyricum EB6
A local bacterial isolate from palm oil mill effluent (POME) sludge, identified as Clostridium butyricum EB6, was used for biohydrogen production. Optimization of biohydrogen
production was performed via statistical analysis, namely response surface methodology(RSM), with respect to pH, glucose and iron concentration. The results show that pH,
glucose concentration and iron concentration significantly influenced the biohydrogen gas production individually, interactively and quadratically (P < 0.05). The center composite design (CCD) results indicated that pH 5.6, 15.7 g/L glucose and 0.39 g/L FeSO4 were the optimal conditions for biohydrogen production, yielding 2.2 mol H2/mol glucose. In confirmation of the experimental model, t-test results showed that curve fitted to the experimental data had a high confidence level, at 95% with t ¼ 2.225. Based on the results of this study, optimization of the culture conditions for C. butyricum EB6 significantly increased the production of biohydrogen
Assessing Road Accident Black Spots and Countermeasures in the State of Perak, Malaysia
To develop a successful strategy for improving road safety, the initial step involves is to identify the black spots that are more susceptible to high-risk traffic accidents. However, due to the high cost of implementing safety measures in these locations, only a limited number of spots/sites can be thoroughly examined with the available funding. Therefore, it is crucial to prioritize the high-risk sites and their corresponding safety measures in order to make the most efficient use of the available finances. Hence, this paper presents black spots ranking and low-cost countermeasures based on the Perak Federal trunk road traffic crash (RTC) data for three years from 2018 to 2020 recorded by the Royal Malaysian Police (RMP). The weightage point method was used for each black spot ranking exercise where as, the selection for countermeasures were based on RTC situations which are norms practiced by the Public Works Department (PWD). In total 22 black spots were ranked and it was found that the highest rank of the 2020 black spots in Perak was along route FT005 in Kinta district which had 18 RTCs and with a total weightage points (TWP) of 118.2. In balancing between limited financial allocation and improving road safety, the countermeasures were priorotized for implementation in 2021 based on the black spots ranking results. However, only six black spots were treated in 2021 with the entire cost was RM 1,834,027.19. Where for route FT005 in Kinta district, the countermeasure was done at Section 684 with a total cost of RM350,000 under the 2022 black spots countermeasure program which is an annual program funded by the Ministry of Works Malaysia. It is recommended that Perak State PWD form a Road Safety Unit to reduce the black spots along the state roads which is the second highest road fatalities recorded in Perak
Comparing Postoperative Sore Throat (POST) following intubation using Macintosh Laryngoscope Versus C-MAC® Video Laryngoscope
Postoperative sore throat (POST) is a common complication with incidence of 30-90% when intubation was done using conventional Macintosh laryngoscope. Although POST is usually self-limiting and with no long-term morbidity, it can lead to patient’s discomfort and dissatisfaction in the postoperative period. The objective of this study was to compare the incidence of POST following intubation using Macintosh laryngoscope and C-MAC® videolaryngoscope (VL) at various time intervals post anaesthesia. This prospective randomised controlled study comprised of 128 patients with American Society of Anesthesiologists (ASA) I and II status who underwent elective surgery under general anaesthesia in Universiti Kebangsaan Malaysia Medical Centre. All recruited patients have normal airway and divided randomly into Group 1 and Group 2 that used Macintosh laryngoscope and C-MAC® VL during intubation, respectively. Patients were evaluated for sore throat, hoarseness of voice, dysphagia and coughing at recovery, 6 hours, 12 hours and 24 hours after intubation. Severity of POST was assessed using numerical rating scale (NRS). Incidence of POST was found to be higher in the Macintosh laryngoscope group (61.9%) compared to C-MAC® VL group (47.9%) although the difference was not statistically significant (p=0.107). Median pain score was used to assess the severity of POST, showing low and comparable in both groups at all time intervals. There were also no significant differences seen in hoarseness of voice, coughing and dysphagia for both groups during postoperation. Incidence of POST following intubation using C-MAC® VL and conventional Macintosh laryngoscope were comparable. This study revealed that severity of POST was generally low in both groups
Association of MMP-9 gene polymorphisms with nephrolithiasis patients
Background: Nephrolithiasis is one of the causes which lead to chronic kidney disease
(CKD). Matrix metalloproteinases (MMPs) are endopeptidases degrading extracellular
matrix which correlate with the pathogenesis of atherosclerosis. The current study
was designed to analyze the association of (R279Q, C1562T) polymorphism of MMP-9
with nephrolithiasis patients.
Methods: Genotyping of MMP-9/R279Q and of MMP-9/C1562T polymorphism
were carried out by PCR-based restriction digestion method. Serum level of MMP-9,
oxidative stress marker, MDA, and uric acid were measured in patients and control.
Results: Allele frequencies of the MMP-9/C1562T polymorphism for C and T allele
were 71.25% and 28.75% in patients, 87.08% and 12.92% in control respectively. The
homozygote TT was more frequent in the nephrolithiasis patients group, while T allele
frequency was significantly higher in the nephrolithiasis patients group than in the
control group. The patients with CT and TT genotype showed a significant increase in
serum MMP-9, Total Oxidant Status (TOS), Oxidative Stress Index (OSI),
Malondialdehyde (MDA), and uric acid when compared to CC genotype in patients
with nephrolithiasis. The R279Q polymorphism site with regard to the relationship
with nephrolithiasis was not significant.
Conclusion: The result indicates that patients with TT genotype had an increased risk
of stones. Also, the results demonstrate that TT allele of the C1562T polymorphism in
the MMP-9gene is related with an increase of oxidative stress in nephrolithiasis
patients and may possibly impose a risk for cardiovascular diseases in patients with TT
genotype of MMP-9
Teacher beliefs and practices in communicative language competence towards the development of an autonomous learning model
There is great impetus for English courses in institutions of higher learning (II-IL) at present due to its functional importance as a tool for individual and national development, graduate employability and life-long learning. However, it remains a common complaint among employers that Malaysian fresh graduates lack English proficiency and critical thinking skills. Thus, this qualitative study sets out to examine the focus and emphasis on English language proficiency, critical thinking skills and study skills of five (5) English courses offered by Universiti Tun Hussein Onn Malaysta (UTHM) through semi-structured interviews, classroom observations and document analysis. The interviews conducted with five teachers and ten students were transcribed using Transana software before being coded for analysis. A grounded theory approach which emphasises on several stages of data collection and constant comparison of data was employed to interpret the data. The main findings revealed that teachers in general
\· think that language proficiency, critical thinking and study skills are important for tertiary level English classrooms. However, actual teaching practices were found to differ from the teachers' beliefs towards critical thinking and study skills due to challenges which can be categorised as teacher factors, student factors and institutional factors. Finally, several important criteria were identified from the findings to form an autonomous learning model for English language communicative competence called the SITE Model. The findings of this study especially the current beliefs and teaching practices of teachers as well as the proposed SITE Model may serve as a reference point for researchers, educators and policy makers to develop effective English language curriculums for enhancing communicative competence among learners