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- PublicationAdaptive Failure Recovery And Path Optimization For Multi-Hop Software-Defined Exchange Point Networks(2025-07)This thesis presents the Enhanced Link Failure Rerouting (ELFR) mechanism, developed to address challenges in failure recovery within multi-hop Software-Defined Exchange Point (SDX) networks. SDX, an evolution of traditional Internet Exchange Points (IXPs), uses Software-Defined Networking (SDN) to enable programmable traffic control. However, multi-hop SDX deployments still face significant limitations, including high packet processing delays, slow path computation, and excessive memory consumption during failures. To tackle these issues, ELFR was designed with two integrated modules: the Packet Processing Module, which allows fast in-switch classification and recovery using P4-defined headers, and the Path Computation Module, which proactively calculates neighbor-based backup paths to lessen controller overhead. The architecture was implemented with Mininet, BMv2, P4Runtime, and the POX controller, and tested across four realistic failure scenarios. Results show that ELFR outperforms the Flow-Aware Pro-Reactive (FAPR) mechanism by reducing Recovery Time (RT) by 46.97%, Computation Time (CT) by 34.62%, and Computational Overhead (CO) by 44.44%, while decreasing Memory Usage (M) by 37.5%. Additionally, it minimizes Packet Processing Delay (PPD) by 28% and Packet Loss Ratio (PLR) by 63.16%. These findings confirm ELFR as an efficient, scalable, and resilient solution for recovering from link failures in programmable SDX infrastructures.
- PublicationA Descriptive Study Of Graffiti Of Palestinians In Refugee Camps In Jordan From The Views Of Sociolinguistics And Sociology Of Language(2025-07)This research was carried out to investigate the graffiti of Palestinians in refugee camps in Jordan from the perspectives of sociolinguistics and the sociology of language to figure out the language functions of the graffiti, linguistic features and rhetorical devices and the social problems that affect Palestinian refugees. To figure out the language functions, the study adopted Jakobson’s (1960) theory, Harris’s (1997) theory, and Erlingsson and Brysiewicz (2017) model. To answer the research questions, a sample of two hundred and forty-four graffiti have been collected from four camps using systematic sampling method. The findings revealed that Palestinian refugees' graffiti served eighteen language functions, highlighting key issues, including expressing patriotism, love and personality, feelings and leaving memories. The findings showed that the graffiti fulfilled eleven linguistic features that fell within the areas of syntax, phonology and semantics. The findings also showed that the graffiti employed sixteen rhetorical devices that were used to glorify resistance, ridicule living conditions, express love and irony, show emphasis, contrast and arouse curiosity.
- PublicationChrononutrition behaviours and physical activity of university students and its association with abdominal obesity(2026-06)Abdominal obesity is an important risk factor for metabolic health problems, while chrononutrition behaviours and physical activity levels are lifestyle factors that may influence metabolic health among university students. This cross-sectional study aimed to investigate chrononutrition behaviours and physical activity levels among 130 students at Universiti Sains Malaysia (USM) Health Campus, and their association with abdominal obesity. Chrononutrition behaviours were assessed using the Malay Chrononutrition Profile Questionnaire, physical activity was measured with the Malay IPAQ-SF, and waist circumference was measured to classify abdominal obesity. The results indicated several unfavourable eating patterns: 56.7% of students reported frequent breakfast skipping (≥4 days/week), 30.7% engaged in late-night eating (≥4 nights/week), and 75.8% identified lunch as their largest meal. Conversely, 80.0% maintained an eating window of ≤12 hours. Regarding physical activity, 72.3% of students achieved at least a moderate level of activity (≥600 MET-min/week). The prevalence of abdominal obesity was 16.2%. Chi-square tests found no significant associations between chrononutrition behaviours and abdominal obesity (p > 0.05), nor between physical activity level and abdominal obesity (p = 0.237). In conclusion, although irregular eating habits were common, neither meal timing behaviours nor activity level were significantly related to abdominal obesity in this sample. The findings provide baseline data on meal timing and physical activity among young Malaysian adults. Continued health education on regular meal patterns and active lifestyles is recommended, and further research with larger samples is needed to confirm these findings.
- PublicationPrevalence and pain intensity of dysmenorrhea and their association with dietary quality among female undergraduate students at Universiti Sains Malaysia(2026-06)Dysmenorrhea is a common gynecological condition among female university students and may adversely affect academic performance, daily activities, and quality of life. This study aimed to investigate the association between dietary quality, prevalence of dysmenorrhea, and pain intensity of dysmenorrhea among female undergraduate students at Universiti Sains Malaysia (USM). A cross-sectional study was conducted among 132 female undergraduate students selected using convenience sampling. Data were collected using a questionnaire consisting of sociodemographic information, a 3-day 24-hour dietary recall, and a dysmenorrhea questionnaire. Dietary quality was assessed using the Standardized Malaysian Healthy Eating Index (S-MHEI). Data were analyzed using IBM SPSS version 31.0. Descriptive statistics were used to summarize the data, while Fisher’s Exact tests were used to determine associations between variables. The mean dietary quality score was 46.55 (SD = 8.57), with the majority of respondents (78.0%) classified as having poor dietary quality. The prevalence of dysmenorrhea was 86.4%. Most respondents experienced moderate pain intensity (55.3%), followed by mild (34.2%), severe pain intensity (8.8%) and 2 of the respondent (1.8%) reported no pain intensity. A significant association was found between dysmenorrhea prevalence and pain intensity (p < 0.001). However, no significant association was observed between dietary quality and dysmenorrhea prevalence (p = 0.323) or pain intensity of dysmenorrhea (p = 0.083). In conclusion, dysmenorrhea was highly prevalent among female undergraduate students and was commonly associated with moderate pain intensity. Although dietary quality was generally poor among respondents, no significant association was found between dietary quality and dysmenorrhea outcomes. Future studies involving larger and more diverse populations are recommended to further investigate the relationship between dietary factors and dysmenorrhea
- PublicationThe association between knowledge, attitude, practice (KAP) on sodium and diet quality among hypertensive patients in Hospital Universiti Sains Malaysia (HPUSM)(2026-06)One in three adults in Malaysia suffers from hypertension. Knowledge, attitudes, and practices (KAP) on sodium play a crucial role in determining diet quality, which in turn helps manage patients' blood pressure. Therefore, this cross-sectional study was conducted to determine the relationship between Knowledge, Attitude, and Practice (KAP) towards sodium intake and dietary quality among hypertensive patients at HPUSM. A total of 180 participants with median age 64 years (63.9% age more than 60). Majority were female (57.2%), Malay (42.8%), earning below RM2000 (58.4%), and unemployed (52.8%). The results showed that the majority of participants had poor knowledge (47.8%), positive attitude (53.3%), inadequate practice (88.9%). Meanwhile diet quality were moderate (70%) and requires improvement, as no participants achieved a good level of diet quality.There was a moderate significant correlation (r = 0.335, p < 0.001) between the knowledge and attitude domains, a weak significant correlation between knowledge and practice (r = 0.169, p = 0.012), and a moderate significant correlation between attitude and practice (r = 0.395, p < 0.001). However, no significant correlation was found between the sodium KAP domains and overall diet quality or sodium intake (p > 0.05). Nonetheless, the median diet quality score among participants with good knowledge was significantly higher (56.100, IQR 31.3) compared to those in the moderate knowledge group (51.350, IQR 55.3) (p = 0.025). In conclusion, although the majority of participants exhibited a positive attitude, their level of knowledge and practice regarding sodium remains poor, thereby influencing their diet quality. Therefore, intervention programs focusing on enhancing knowledge and practice are essential to translate patients' positive attitudes into better diet quality.
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- PublicationStability control for sea drone(2024-07)This project focuses on developing a gyrostabilizer-based stability control system to enhance sea drone performance in challenging marine environments. Leveraging the advanced technology of Seakeeper, known for its effectiveness in large marine vessels, this project aims to adapt and miniaturize the gyrostabilizer for use in small-sized unmanned surface vehicles (USV). The system integrates gyrostabilizers to counteract destabilizing forces like waves, employing Proportional-Integral (PI) and Linear Quadratic Regulator (LQR) controllers to optimize and compare performance under varying sea conditions between both controllers. The project unfolds in four stages: fabricating the gyrostabilizer, tuning and simulating the controllers, testing their effects and conducting field tests on a monohull USV. The active control system uses an MPU6050 Inertial Measurement Unit (IMU) to detect wave motion, a brushless direct current (BLDC) motor to operate the flywheel and a servo motor to control the gyrostabilizer's precession angle, dissipating wave disturbances. Evaluation results show the PI controller outperforms the LQR controller, reducing stabilization time by 95.42% when an external force applied on the USV while mean roll angle reduces by 34.19% and roll variability reduces by 56.32% in rough sea conditions. Conversely, the LQR controller reduces stabilization time by 91.15% when an external force applied but increases the mean roll angle by 135.87% and reduces roll variability by 58.12% in rough sea conditions. These findings highlight the PI controller's superior performance in enhancing sea drone stability in rough sea conditions.
- ItemEvaluation Of Rice Husk Powder As An Anticaking Agent In Coffee Powder(Universiti Sains Malaysia, 2020-07)Synthetic anticaking agents have been widely used to solve powder caking. However, the increasing concern of consumers leads to the rising demand on clean labels. Potential natural ingredients such as rice husk which has high water adsorbing ability are yet to be studied and developed as anticaking agents. This study aims to evaluate the effectiveness of rice husk powder as an anticaking agent in coffee powder, specifically by characterisation, optimisation and study of moisture sorption isotherm. In this study, rice husk was milled into different size classes of powder (<75 μm, 75–250 μm and 250–500 μm). Characterisation was conducted based on silica content, fibre content, particle size and distribution, and particle morphology. Five samples prepared were control sample and coffee powder containing different amount of rice husk powder (1.0%, 1.7% and 3.0%) and 1.7% silicon dioxide (commercial reference). Samples were equilibrated with different relative humidities (23%, 43% and 62%) to prepare moisture-equilibrated samples. Anticaking properties were evaluated based on colour, moisture sorption isotherm and flowability. Rice husk powder had relatively high silica content and fibre content, with mean experimental values of 16.96% and 41.83% respectively. Size class of <75 μm had the greatest anticaking ability due to its smallest particle size and widest distribution. Particle morphology showed extensive layers of fibre-silica matrix with interlayer spaces. Relative humidity and amount of rice husk powder had significant impact on colour of the samples. Flowability increased with increasing amount of rice husk powder but decreased with increasing relative humidity. Samples subjected to 62% relative humidity were completely caked.
- ItemInvestigation Of Hydraulic Performance On Unsymmetrical Smooth Spillway(Universiti Sains Malaysia, 2021-06-01)The smooth spillway is a classic design used to spill large volume of water from the dam reservoir. Several studies of hydraulic characteristics of the spillway have been conducted experimentally and numerically in recent decades to provide a better insight into flow behaviour and predict any critical area that could endanger the structure and environment. An experimental study was carried out on a laboratory scale model to investigate basic hydraulic characteristics of the unsymmetrical smooth spillway with three sizes of discharge namely as Q1, Q2 and Q3. Next, the simulation verification were done using grid independent test (GIT), time step size analysis, and simulation time observation. In simulation, Reynolds-averaged Navier-Stokes (RANS) equation, volume of fluid (VOF) scheme and Standard κ-ω (SKW) turbulence model with appropriate boundary conditions were used to simulate the unsymmetrical smooth spillway geometry with four sizes of discharge namely as Q1, Q2, Q3 and Q4. The simulation results provide a good prediction of the hydraulic characteristics of water flow on the unsymmetrical smooth spillway and show a good agreement in terms of water surface and velocity profiles patterns with the experimental results. In the last objective, four chute piers modification models (diverge -45 degree, diverge -15 degree, converge 15 degree and converge 45 degree) were simulated using Q3 and Q4 discharge water flows and the hydraulic jump performance of all models were compared with the normal geometry. For all modification models, the converge 15 degree model showed 5.06% and 2.49% higher energy dissipation than the normal geometry model using Q3 and Q4, respectively. The chute piers modifications on unsymmetrical spillway will affect the energy dissipation performance at stilling basin and provide good insight which can be considered for spillway design in the future.
- ItemAntidiabetic Activity Of Nypa Fruticans WURMB. Vinegar(Universiti Sains Malaysia, 2017-02)Nypa fruticans Wurmb. vinegar, locally known as nipa palm vinegar (NPV) in Malaysia, is believed to have remarkable antidiabetic properties. This study sought to elucidate the vinegar’s antidiabetic activity and possible mechanisms of action. Liquid– liquid extraction was used to separate the compounds in NPV based on polarity into an ethyl acetate extract (EE) and an aqueous extract (AE). AE was further fractionated using acid hydrolysis into two sub-fractions: SFI and SFII. NPV, EE, AE, SFI and SFII were administered using oral gavage in non diabetic and/or diabetic rats induced by streptozotocin (STZ). Blood glucose levels (BGLs), insulin levels, and liver and pancreatic histological changes were recorded. In vitro effects of AE on α–glucosidase and α–amylase activities, as well as on glucose absorption/ uptake in isolated rat jejunal sacs/ skeletal muscles; were observed. No acute hypoglycemic effect was shown in non diabetic rats upon administering up to 1 g/kg of NPV, EE or AE. Nevertheless, NPV and AE significantly ameliorated high BGLs at 90 minutes in glucose-loaded rats. Yet, administration of NPV, EE and AE to STZ-induced diabetic rats showed no antihyperglycemic effects for up to 7 h. Sub-chronic 12-day oral treatment in diabetic rats revealed that AE had a superior antihyperglycemic activity overall. Immunohistochemical assessment of the animals’ pancreatic tissues showed that, albeit having no regenerative effect, AE stimulated the secretion of insulin from viable β– cells. It also precipitated structural recovery in the liver. It lowered BGLs, improved serum insulin levels and normalized the lipid profile of the animals, with no signs of gastric ulcer or abnormal body weight gain/loss. Consequently, AE was chosen for xvii elaborate antidiabetic mechanism studies. In vitro tests showed that AE inhibited the absorption of glucose from jejunum.
- PublicationDevelopment and characterization of flowable composite derived from rice husk using urethane dimethacrylate(2025-09)The study aimed to develop and characterize flowable composites (FCs) using silica derived from rice husk as the primary filler, urethane dimethacrylate (UDMA) as the base monomer, and zirconia as the radiopacifying agent. The resin matrix combined UDMA with triethylene glycol dimethacrylate (UDMA:TEGDMA) at ratios of 20:80, 30:70, 50:50, 60:40, 80:20, and 90:10. Commercial FCs, including Revolution Formula 2, G-aenial Universal Flo, and Filtek Supreme Flowable Composite, were used for comparison. The newly developed FCs were categorized into high (20:80, 30:70), medium (50:50, 60:40), and low-flow (80:20, 90:10), based on the flowability evaluation. These newly developed FCs were subsequently characterized for their chemical, physical, and mechanical properties, as well as polymerization shrinkage. Data were statistically analyzed using one-way ANOVA, followed by posthoc Tukey or Games-Howell tests for comparison, except for the depth of cure, which was analyzed using the Kruskal-Wallis. The chemical properties, assessed through Fourier transform infrared (FTIR) and degree of conversion analyses, confirmed the presence of silica and zirconia in the newly developed FCs and showed an increase in the degree of conversion with higher UDMA ratios (55.38 – 68.58%). The physical properties evaluated included radiopacity, viscosity, depth of cure, surface roughness, water sorption and solubility, and wettability. The newly developed FCs at all ratios were radiopaque (2.87 – 3.06 mmAl) and passed the International Organization for Standardization 4049 (ISO 4049) requirement. As the UDMA ratio in the newly developed FCs increased, both viscosity and depth of cure increased Improved surface roughness and reduced water sorption were also observed with higher UDMA ratios. For solubility, the values were independent of the UDMA ratios. Wettability, assessed through contact angle measurements, revealed a significant increase in contact angle after polymerization, indicating a shift from hydrophilic (24.218 – 50.617º) to more hydrophobic behaviour (85.901 – 88.669º). The mechanical properties evaluated included Vickers hardness, flexural strength and modulus, and compressive strength and modulus. Most properties improved with increasing UDMA ratios, with some flexural strength values (79.61 – 102.1 MPa) meeting the requirement of ISO 4049. Polymerization shrinkage was also reduced as the UDMA ratio increased. Overall, higher UDMA ratios (80:20, 90:10) exhibited superior chemical, physical, and mechanical properties, along with reduced polymerization shrinkage. Moderate (50:50, 60:40) and lower UDMA ratios (20:80, 30:70) demonstrated intermediate and inferior performance, respectively. These findings suggest that the newly developed FCs, particularly at higher UDMA ratios, could serve as viable alternatives to commercially available FCs, supporting a green-based industry that reduces waste and promotes sustainability