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Ecology of Indo-Pacific Humpback Dolphin (Sousa chinensis) and Irrawaddy Dolphin (Orcaella brevirostris) in the Matang mangrove and adjacent coastal waters in Peninsular Malaysia / Kuit Sui Hyang
No full textThe coastal waters of Matang in Perak, Peninsular Malaysia, are internationally designated as the Matang Mangroves and Coastal Waters Important Marine Mammal Area (IMMA) by the International Union for Conservation of Nature (IUCN). As ecological baseline data were lacking on coastal delphinids that are threatened by anthropogenic activities, this Ph.D. study was conducted to contribute new scientific knowledge and critical understanding of the animals’ ecology in the coastal waters of Matang. Boat-based surveys were conducted from 2013 to 2016, while interview surveys with local fishers were conducted from 2014 to 2017 to determine the abundance, distribution and habitat characteristics, movement and ranging patterns, and human-dolphin interactions of Indo-Pacific humpback dolphins (Sousa chinensis) and Irrawaddy dolphins (Orcaella brevirostris). The abundance estimates of Irrawaddy dolphins in Matang were 763 individuals (CV = 13.3%; 95% CI = 588-990), estimated via line-transect distance sampling. Annual abundance estimates of Indo-Pacific humpback dolphins (hereafter humpback dolphins) via mark-recapture fluctuated from 138 individuals (95% CI = 118-162) in 2013-2014 to 171 individuals (95% CI = 148-208) in 2014-2015, to 81 individuals (95% CI = 67-98) in 2015-2016, likely due to the presence of offshore individuals that moved in and out of the study area. The humpback dolphins exhibited a clustered distribution and were mostly found closer inshore in the shallow estuarine waters and riverine waterways that are less than 10 m deep. The Irrawaddy dolphins had a relatively homogenous distribution and were mostly found in farther coastal waters that are less than 15 m deep. The core areas of feeding and nursery grounds of humpback dolphins were mainly in the estuaries of Kuala Sangga Besar, Kuala Larut and Kuala Jarum Mas. As for Irrawaddy dolphins, the core areas of feeding and nursery grounds were mainly around the coastal waters off Kuala Larut and Kuala Trong. The core areas of these two species overlapped minimally, and likely reflected the distribution of preferred prey resources, species interactions, their differential responses to anthropogenic activities and species dominance. The Minimum Convex Polygon (MCP) ranges of 13 inshore resident humpback dolphins overlapped considerably in the estuaries, where the animals remained within 7 km from shore with a mean MCP range of 217.4 ± 65.2 km2. This ranging pattern in the estuaries is most likely linked to their use of the productive estuarine habitats by optimizing the exploitation of their estuarine prey aggregations that are tidal-driven. Out of 198 local fishers interviewed, 14% (n = 28) had cetacean bycatch that mostly occurred in gillnets and trawl nets. The prevalence of anthropogenic injuries in Irrawaddy dolphins (28.5%) and humpback dolphins (16.5%) also indicated interactions with fishing gears that could threaten their survival. A bycatch risk assessment (ByRA) revealed medium to high dolphin bycatch risk in gillnets and trawl nets throughout most of the study area. This study established important baseline information for future studies to identify abundance trends and habitat shifts, and identified areas that should be prioritized for conservation and habitat management
Mental health disorders among Rohigya refugees in Malaysia / Kushilpal Kaur Satwant Singh
No full textMental health disorders among refugees has been recognized as a major public health
issue. However, to date, there is limited evidence on the prevalence of Mental health
disorders among Rohingya refugees residing in transit countries such as Malaysia. This
study aimed to examine the prevalence and associated factors of Major Depressive
Disorder (MDD), generalized anxiety disorder (GAD) and post-traumatic stress disorder
(PTSD) among Rohingya refugees in Malaysia. Adult Rohingya refugees residing in
Selangor (n= 220) were randomly selected to participate in this cross-sectional study that
was conducted from June to November 2019. Perceived social support, religious
orientation, and food security was assessed using the Multidimensional Scale of
Perceived Social Support (MSPSS), Religious Orientation Scale-Revised (ROS-R) and
the Radimer/Cornell food insecurity instrument. Mini-International Neuropsychiatric
Interview (MINI) was used to examine MDD, GAD, and PTSD. The prevalence of GAD,
PTSD, and MDD was reported at 92 (41.8%), 84 (38.2%) and 71 (32.3%). Several factors
were significantly associated with MDD following multivariate analysis namely being
female (AOR = 2.54; 95% CI 1.21, 5.34), living in Malaysia for less than 1 year (AOR =
6.95; 95% CI 1.89, 25.57), having been physically injured (AOR = 3.25; 95% CI 1.52,
6.96), perceived low/moderate social support (AOR = 2.17; 95% CI 1.13, 4.19) and food
insecurity (AOR = 2.77; 95% CI 1.19, 6.47). Exposure to violence (AOR = 38.46; 95%
CI 16.27, 90.91) and food insecurity (AOR = 3.74; 95% CI 1.41, 9.91) were significantly
associated with PTSD. The findings of this study provide new evidence relating to the
burden and risk factors of Mental health disorders among Rohingya refugees residing in
Malaysia, addressing these risk factors could improve mental health among this
population
A two-warehouse inventory model with rework process and time-varying demand / Nurnadiah Nurhasril
No full textIt is commonly assumed that in a classical inventory model, all items produced during
a production cycle are of perfect items. However, contradictory to reality, production
processes are not perfect at all times, hence resulting in the production of defectives. In
order to minimise the cost incurred and reduce wastage in a production process, we might
consider a rework process to be implemented on the defective items. Besides that, most
classical inventory models also consider the assumption that the available storage facility
has an unlimited capacity. Conversely, in reality an additional storage space commonly
known as a rented warehouse (RW) is needed to store excessive inventory. Another
common assumption is that the demand rate is constant. However, contrary to reality
the demand rate is known to fluctuate due to several factors such as trends and seasons.
Therefore, in order to take into consideration all of the aforementioned common assumptions,
we proposed a two-warehouse inventory model with deteriorating items and rework
process with time varying demand rate. We also considered the Last-In-First-Out (LIFO)
and the First-In-First Out (FIFO) policies with the assumption that the holding cost is
higher in the rented warehouse as compared to the owned warehouse. The objective of the
proposed model is to determine the optimum values of the time period in a cycle of stage
i that will minimise the total relevant cost, TRC of a production cycle. This dissertation is
divided into several sections, where we will discuss the mathematical formulation of the
model followed by numerical example and a sensitivity analysis to illustrate the derived
results
Design, fabrication and analysis of novel dragonfly-bioinspired, flapping wing system for a micro air vehicle / Erfan Salami
No full textIn the recent decades, the design and development of biomimetic micro air vehicles (BMAV) have gained increased interest from the global scientific and engineering communities. This has given greater motivation to study and understand the aerodynamics involved with winged insects. Dragonflies demonstrate unique and superior flight performance than most of the other insect species and birds. They are capable of sustained gliding flight as well as hovering and are able to change direction very rapidly. Pairs of independently controlled forewings and hindwings give them an agile flying ability. There are still many technological challenges involved with designing the BMAV. One of these is designing the ultra-lightweight materials and structures for the wings that have enough mechanical strength to withstand continuous flapping at high frequencies.
In this study, biomimicry of a dragonfly wing (frame structure and membrane) is done by fabricating them with different materials: acrylonitrile butadiene styrene (ABS), polylactic acid (PLA), high impact polystyrene (HIPS) and Ultrat. Since it is extremely difficult to fabricate the complex microstructures of an actual dragonfly wing, the fabricated wings (forewing and hindwing) are simplified replications of the actual wing set. This simplification was performed using the spatial network analysis method. The BMAV wings were fabricated using a 3D printer, based on these simplified models. Nanoindentation tests of the actual dragonfly wings and the BMAV wings were conducted to measure their hardness and Young’s modulus. Analysis of these measurements forms a structural engineering basis that is important for future BMAV wing design. The test result demonstrates the feasible solution in the development of strong, practical, and low-cost BMAV wings, this work is a stepping-stone on the path to flying robotic dragonfly.
These wings were then attached to an electromagnetic actuator and passively flapped at frequencies of 10–250 Hz. A three-dimensional high frame rate imaging system was utilized to capture the flapping motions of these wings at a resolution of 320 pixels x 40 pixels and 35000 frames per second. The maximum wing tip deflection, maximum bending angle, maximum wing tip twist angle, and wing tip twist speed of each wing were measured and compared to each other and the real dragonfly wing. The outcomes display that the ABS wing has considerable flexibility in the chordwise direction, whereas the PLA and Ultrat wings show better conformity to a real dragonfly wing in the spanwise direction. Earlier investigations have indicated that the aerodynamic performance of a BMAV flapping wing is improved if its chordwise flexibility is increased and its spanwise flexibility is reduced. Therefore, the ABS wing (fabricated using a 3D printer) shows the most promising results for future applications.
This article presents a novel inexpensive 3D printed tandem flapping wing system that was used to experimentally investigate the aerodynamic forces. Such a system was yet to be investigated and could be used in a future biomimetic micro air vehicle (BMAV) design. The mechanism uses an electromagnetic actuator to flap the wings in a linear up-down stroke motion with a variable beat frequency (30 to 210 Hz) at various angles-of-attack (-10° to 20°). The results show that the tandem wings generate approximately 50% higher lift, compared with the forewing or hindwing pairs acting alone. The tandem wings also improve stability, which could potentially allow hovering
Translation and validation of the self-compassion scale from English to bahasa Melayu among local students in a Malaysian public university / Ross Stephenson
No full textSelf-compassion is a growing area of research worldwide and has shown promise to be useful in providing insight and intervention against rising mental health issues. Self-compassion has also been linked to psychological well-being as well as negative psychological outcomes, which makes it an ideal measure for mental health. However, the instrument to measure self-compassion has not been comprehensively translated and validated in Malaysia yet. Previous studies are lacking in the psychometric evidence for a valid self-compassion scale in a local context. This study presents the comprehensive translation and validation of the 26-item self-compassion scale (SCS) by Neff (2003) from English to Bahasa Melayu (BM). The curent researcher first translated the SCS from English to BM using the backtranslation method. Cognitive interviews were conducted as a form of response validity. The first translation was pilot tested with 60 participants and internal consistency was found to be good. The translation was then reviewed and all items were retained but nine items were edited to make the translation more accurate. The SCS-BM was then administered to a total of 302 participants (M age = 21.9, SD age = 4.1) . Confirmatory factor analysis on the SCS-BM supported the original 6-factor model proposed by Neff (2003). Construct validity was demonstrated through a significant positive correlation between the SCS-BM and the SWLS-BM and a significant negative correlation between the SCS-BM and the BDI-BM. Test-retest reliability obtained after a 3-week interval was found to be acceptable. The translated SCS-BM produced by this study is a reliable and valid measure that can be further used to assess self-compassion in Malaysia
The effectiveness of cooperative learning in enhancing students’ vocabulary for speaking / Ong Si Juan
No full textTraditionally, English classes in Malaysian schools are rather teacher-centred and this method tends to impede students’ speaking skills. Coupled with the lack of vocabulary, it exacerbates their difficulty in using appropriate expressions in their speaking skills. Attempting to address these problems, the researcher used the Cooperative Learning (CL) method in her study because research has shown that it benefits greatly from the social interaction between students and improves the students' speaking skills, as its structured interaction design facilitates the accomplishment of group goals. This study examined the effectiveness of the CL framework in elevating L2 students’ vocabulary knowledge which consequently led to the improvement of their English-speaking skills. The study uses a quasi-experimental design which involves 80 participants from a Chinese primary school in Malacca, Malaysia, using convenience sampling to allocate participants to the treatment group and the comparison group. The treatment group underwent the CL method while the comparison group experienced the traditional teaching method. Pre-test and post-test were used to compare results within and between groups to determine the efficacy of CL in this study. A post-intervention questionnaire and focus group interviews were then carried out with the experimental group to obtain data on their perception of CL. Finally, a survey on the use of English was conducted with both groups to establish what other problems they faced in speaking English. The results were analysed quantitatively and qualitatively. The quantitative results revealed better development in the students’ mastery of vocabulary in speaking after the cooperative learning treatment compared to the traditional method. The qualitative findings revealed positive attitude towards the CL method of learning vocabulary. The findings on other problems they faced in speaking in English can be used to inform future research in this area especially among L2 learners. There were some challenges in completing this study as time management was crucial when working in groups. The limitations of this study are that CL was applied to only a year grade of primary school students and the duration of the treatment was only 6 weeks. Therefore, any attempt to replicate this study should consider a longer timeframe and involve different year grades to ensure consistency in results and for finer-tuned findings
Abundance of mesoplastic on beaches, microbial profiles and coastal water quality analysis at selected islands in Peninsular Malaysia / Logananthini Muniandy
No full textThe marine environments including beaches around the world are littered with numerous
types of waste particularly plastics. In Malaysia, there is increasing evidence of an
extensive abundance of small plastic debris in coastal areas. The appearance of these
plastics in coastal water might affect the quality of water and microbial organisms in it.
Thus, this study aims to determine the mesoplastics (1 – 30 mm) abundance at the
shorelines, coastal water quality, and microbial profiling at eight selected beaches.
Triplicate sediment samples were collected from the top layer until 5 cm depth using a 50
× 50 cm quadrat. The separation of sediments and plastics was done using the nest sieving
method. The mesoplastics were sorted and categorized by type and quantity based on the
beach attributes. The water quality and microbiological parameters were determined by
collecting triplicate coastal water samples at 3 m and 6 m distance from the shoreline and
analyzed using standard methods. A series of physicochemical parameters namely
temperature, dissolved oxygen (DO), pH, conductivity, salinity, turbidity, biochemical
oxygen demand (BOD), total suspended solids, total dissolved solids, nitrate, ammonium,
phosphate, and silicate were determined in this research. The microbial formation in
coastal waters was analyzed using total heterotopic bacterial count and total coliform as
indicators. A total average of 2631 ± 367 items/m2 of mesoplastics was collected from all
the sampling sites. The highest mesoplastics were found at Pinang Seribu beach, Pulau
Perhentian with 1112 ± 30 items/m2, and the lowest mesoplastics at Jeti beach, Pulau
Besar with 20 ± 4 items/m2. The study indicates that the occurrence of marine debris at
these beaches was not mainly caused by anthropogenic activities in that area but also was
brought in from the sea. This may due to the physical condition and the beach position which tends to trap the marine debris from offshore. In addition, the ranges for the
physicochemical parameters were 24.7 – 35.6oC for temperature, 2.20 – 7.87 mg/L for
DO, 5.50 - 8.53 for pH, 36878 - 5226 μS/cm for conductivity, 32.42 – 33.81 ppt for
salinity, 18.5 – 19.89 NTU for turbidity, 52.0 mg/L – 89.5 mg/L for BOD, 25.0 – 160.0
mg/L for TSS, 12.4 - 31.65 mg/L for TDS, 42.4 – 943.6 μg/L for nitrate, 47.3 – 353.6
μg/L for ammonium, 56.6 – 673.2 μg/L for phosphate, and 32.2 - 99.1 μg/L for silicate.
Based on the water quality analysis, as per MMWQS, all the beaches fall within the limit
suitable for recreational use. The most polluted beach was Pinang Seribu with low DO
and high BOD, and TDS levels. The least polluted beach was Jeti beach with high DO
and low levels of BOD, phosphate, and silicate. Moreover, the heterotopic bacterial count
at all the sampling sites varied from 0.75 – 3.08 × 108 CFU/mL. The total quantity of
coliforms at overall beaches were in the span of 22.64 to 50.84 × 108 MPN/100 mL. The
highest amount of bacteria was observed at Pasir Belakang Beach and the lowest number
was at Tengah Beach. The presence of mesoplastics in sediments on the selected beaches
does not influence microorganisms in the seawater at that coastal line
The roles and functions of metaphors in the Malaysian Education Blueprint / Linggatharani Kesavan
Get PDFAbstract: The Malaysian Education Blueprint (2013 - 2025) seeks to revamp the entire education system in Malaysia, targeting institutions of learning and the stakeholders via a series of radical changes in policy and governance. Upon scrutiny, it was also found to contain several metaphors that are carefully constructed and layered to deliver the contents to the readers. Metaphors have been identified as an effective linguistic tool that can be used to achieve cognitive, semantic and pragmatic goals effectively. More importantly, they are also found to create or alter realities and evoke powerful emotions. This research applies the Conceptual Metaphor Theory (CMT) developed by Lakoff and Johnson (1980) to explore the metaphorical concepts in the Malaysian Education Blueprint (2013 – 2025). Additionally, Charteris-Black’s (2004) framework of analysing metaphorical data in a corpus was employed to study the functions and the role metaphors play in the document. This research found that the metaphorical concepts in the blueprint were systematically employed to represent complex policies and the changes proposed for the next twelve years in the education system. The document also effectively used metaphors to present the issues and challenges faced by the education system in a more palatable way. Moreover, by using military metaphors, the document was found to conceptualize the seriousness of the government in creating an improved education system for the future by taking on current issues
Effect of imagery and heart rate variability biofeedback training on selected soccer skills performance / Sara Majlesi
No full textThe present study aimed to evaluate the influence of PETTLEP video imagery (Physical, Environment, Task, Timing, Learning, Emotion and Perspective), heart rate variability biofeedback (HRVB), and concurrent intervention of both on selected soccer skill performances. The objective of this study was to evaluate the effect of PETTLEP video imagery, HRVB and concurrent intervention on soccer players' reactive motor skill test (RMST), sprint time, reactive agility, passing time, and passing accuracy. Participants of this study were Malaysian high school soccer players (N=64), with mean age of 15.31±1.83, who were assigned randomly into four groups: three experimental groups and one control group. Each group had 16 players who were assigned randomly through the fishbowl method. Method: A Pre-test and Post-test design were used in this study to evaluate the effect of interventions on the players' skill performance. The three experimental groups received PETTLEP video imagery, HRVB, and concurrent (HRVB + PETTLEP video imagery) training for eight weeks in addition to their regular soccer training, while the control group only attended their regular soccer training. The experiments developed in this study consisted of a 10-minute PETTLEP video imagery training for imagery group, a 10-minute breathing exercise using the Elite HRVB app to feedback players' breathing to 5.5-6 BPM resonant breathing for HRVB group, and a 5- minute HRVB training using Elite HRVB app and a 5-minute PETTLEP video imagery training right after HRVB training for the concurrent training group. After the eight weeks of training was completed, the RMST test was administered to all participants to measure the changes in their RMST, sprint time, reactive agility, passing time, and passing accuracy. The data were analyzed with a factorial MANOVA test to evaluate the differences within and between groups. Results: Five research hypothesis of the study were supported, and statistically significant effects of experimental training on players' performance were demonstrated among all groups and within the groups. Statistically significant differences were observed between the pre-tests and the post-tests, p < .001 among all groups. The multivariate results were statistically significant differences between and within groups and also there was a statistically significant interaction effect between tests and groups of intervention on the combined dependent variables, F(15, 154.993) = 20.280, p < .001, Wilks' Λ = .050. Furthermore, the univariate interaction effects results showed all the dependent variables have statistically significant differences individually between and within groups. There was a statistically significant interaction effect between tests and type of intervention for RMST, F(3, 60) = 100.593, p = 0.001, sprint time, F(3, 60) = 42.678, p = 0.001, Reactive Agility, F(3, 60) = 173.644, p = 0.001, passing time, F(3, 60) = 34.868, p = 0.001, and Passing Accuracy, F(3, 60) = 21.018, p = 0.001. The interaction between test and type of interventions showed that 3 different types of intervention in this study were effective on each RMST component improvement differently. The Pre-test-Post-test results showed that RMST, reactive agility, passing time, and passing accuracy were statistically different within groups except for the sprint time, which was not significant in the imagery group while it was significant in other groups. The findings of this study provide evidence that eight weeks of imagery, HRVB, and concurrent interventions significantly improved soccer players' RMST, sprint time, reactive agility, passing time, and passing accuracy test results. However, concurrent intervention group showed greater improvement than the other groups, followed by the HRVB intervention group and PETTLEP video imagery group
Chemical health risk assessment at the thermodynamic laboratory, University of Malaya / Goh Zhi Kee
No full textUse of chemicals in university laboratory is unavoidable as it is part of the teaching and learning process. Chemical exposure could lead to acute or chronic occupational diseases and even leads to fatality if the chemical is not handled properly. Therefore, chemical health risk assessment (CHRA) plays an important role to evaluate the risk of chemical hazardous to health used at the Thermodynamic Laboratory, University of Malaya, by referring to the Manual of Recommended Practice on the Assessment of the Health Risks Arising from the Use of Chemicals Hazardous to Health at the Workplace 3rd Edition. The assessment was divided into 3 main phases, which are data collection, on-site assessment, and risk evaluation. Action priority was assigned for each chemical assessed to establish the action plan if further control measures needed. Methanol is required for the highest priority as it has the highest risk rating for both inhalation and dermal, followed by benzoic acid, boric acid, diethanolamine, ethanolamine, silver oxide and sulfuric acid as these chemicals resulted high risk for dermal exposure. The management shall consider to give the access permission to handle these chemicals only to the authorized personnel. This study is beneficial to the university management in order to comply to the Occupational Safety and Health (Use and Standards of Exposure of Chemicals Hazardous to Health) Regulations 2000 as chemical health risk assessment is mandatory to be conducted at workplace in every 5 years