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- PublicationTwo-dimensional depth-averaged Simulation of Mudflow Propagation With Gate-lifting effects.(2025-04)In dam-break experiments with water, the gate-lifting process significantly influences flow propagation. However, in mudflow dam-break experiments, the impact of the gate-lifting effect remains underexplored. This study presents a twodimensional depth-averaged mudflow simulation model using the Constrained Interpolation Profile (CIP) scheme, incorporating the Herschel-Bulkley rheological model to capture mudflow behaviour. One of the objectives is to investigate the gatelifting effect on mudflow propagation. Before analysing mudflow behaviour, the numerical model is first validated for inviscid fluid simulation. The developed model demonstrates its reliability by qualitatively replicating the flow depth profile and velocity variations of Akoh’s third-order model, validating its capability to accurately simulate inviscid fluid flow. Further validation is conducted for mudflow simulation, where similar propagation results such as matching gradients during the viscous phase produced by both the developed model and Puay’s integral model validate the reliability of the developed model in mudflow simulation. To examine the gate-lifting effect, dam-break mudflow simulations are performed and compared with experimental data from previous research. Simulations revealed that neglecting the gate mechanism led to faster initial flow propagation, but this effect weakened as rheological properties began to dominate the flow behaviour. However, the gate-lifting effect has a permanent impact on flow spreading and the surge profile. Additionally, one of the objectives in this study examines the influence of rheological parameters on mudflow propagation, showing that within the yield stress range of 78-109 Pa and plastic viscosity range of 32.10-75.84 Pa·s⁻ⁿ, higher yield stress and plastic viscosity result in shorter flow propagation due to increased flow resistance. The results align well with theoretical predictions, indicating that the developed model can reproduce mudflow behaviour across a range of rheological parameters. These findings contribute to a better understanding of mudflow dynamics in dam-break scenarios and enhance numerical modelling method for hazard assessment and mitigation in mudflow-prone regions.
- PublicationStudy of potential centralized waste Water treatment plant to improved Effluent from livestock area using Infoworks ICM: A case study in sungai Kereh and kampung Selamat.(2025-12)Sungai Kereh was classified as a polluted river in 2020, with Water Quality Index (WQI) values ranging from 31 to 55 (Class III–IV). Persistent odour and poor water quality have severely impacted the daily lives of nearby residents. To evaluate the river’s condition, field sampling was conducted on twelve non-consecutive days from September to November 2021 at six sampling points along the river. Six key water quality parameters—Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Ammoniacal Nitrogen (NH₃-N), Dissolved Oxygen (DO), pH, and Suspended Solids (SS)—were analyzed to compute the WQI. Findings indicate that NH₃-N, BOD, and COD are the primary pollutants, with upstream of Parit Cina (SK1) identified as the main pollution source. Field observations and comparative analysis confirmed that wastewater from pig farming activities in Kampung Selamat is being directly discharged into Parit Cina, significantly elevating pollutant concentrations. To mitigate pollution, water quality modelling was conducted using InfoWorks Integrated Catchment Modelling (ICM) software. Among the scenarios evaluated, Scenario 2—positioning a centralized wastewater treatment plant (CWTP) at the outlet of Parit Cina—showed the highest pollutant removal efficiency. Simulated effluent concentrations were reduced from 130 mg/L to 23 mg/L for NH₃-N, 94 mg/L to 9.4 mg/L for BOD, and 130 mg/L to 19.5 mg/L for COD, achieving over 80% reduction. The post-treatment simulation indicated a substantial improvement in river WQI, with most segments reaching Class III and downstream areas improving to Class II. This study demonstrates the critical role of targeted wastewater treatment infrastructure in restoring river health and provides a strategic framework for water quality management in livestock-intensive catchments.
- PublicationDevelopment of multi-functional Porous materials for oil spill Remediation.(2025-12)In this work, a series of multi-functionalized porous materials, specifically Ceiba pentandra (L.) derived biochar, chitosan and sepiolite have been successfully prepared from lignocellulosic biomass and natural resources via hydrothermal, microwave, and ultrasonic synthesis techniques. The physical, chemical and physiochemical properties of these multi-functionalized porous materials, in term of surface porosity, morphology, contact angle and functionalities were examined using nitrogen adsorption-desorption isotherm, scanning electron microscopy, goniometerand Fourier-Transform Infrared (FTIR) spectroscopy. The performance evaluation was conducted using batch adsorption experiments with respect to the mineral oil (diesel), natural oil (palm oil), and crude oil (petroleum crude). The governing parameters including the effects of contact time, initial concentration, pH and salinity were evaluated. The isotherm modelling, adsorption kinetics, and mechanism of the treatment process were established. Results revealed that these newly prepared adsorbents have been enriched with multi surface porosity, discrepancy morphology and unique functionalities, in supporting the environmental application for oil spill remediation. Examination of the textural structure verified pore development, with a series of cavities distributed around the surface, with the Brunauer-Emmett-Teller (BET) surface areas ranging from 161.72 to 970.42 m2/g. Morphological study supported the presumption that the intercalation of sodium dodecyl sulphate (SDS) and N-Cetyl-N,N,N-Trimethylammonium bromide (CTAB) modification process was successfully attained. Alteration of Fourier-transform infrared spectroscopy (FTIR) bands signified the modification and development of the new functionalities on the functionalized porous adsorbent. Equilibrium analysis has documented their excellent capability for the adsorptive uptakes of diesel, palm oil, and petroleum crude, well fitted to the Langmuir isotherm model (R2=0.998–0.999), with the monolayer adsorption capacity (Qo) at 563.44 mg/g, 678.27 mg/g, and 842.25 mg/g for CCP, SDSC, and CTABS, respectively, while adsorption kinetic was best described by the pseudo-second order model. The adsorptive uptake of oil was found to be highly pH dependent, favouring the adsorption uptake of oil at the acidic condition, where the presence of hydrogen ions could protonated the adsorbent surface, and the changing degree of ionization could promote intensive electrostatic interaction between the adsorbent surface and oil contaminants in its anionic form. In parallel, high salinity is detrimental to organics uptakes, but low salinity can be beneficial for the adsorption process, in which an extreme salinity would lead to salting effect. The results elucidated the adsorptive interaction were governed by electrostatic interactions, π–π stacking, and hydrogen bonding. The well-crafted structural properties and high adsorptive potentials, supported by the environmentally sustainable preparation approaches, have positioned them as viable solutions for the effective remediation of oil contamination. The core insight from the research will serve as a transformative concept, advancing the innovative idea of 'Turning Waste into Wealth' to mitigate oil spill issues sustainably in an eco-friendly manner.
- PublicationStudies on relationship of water Quality and mosquito breeding in Constructed wetland.(2025-12)Mosquito breeding in constructed wetlands presents a public health risk, particularly with the potential proliferation of Aedes species, vectors of dengue and other mosquito-borne diseases. Although constructed wetlands are designed for water treatment and ecological enhancement, their stagnant water zones and dense vegetation can inadvertently create favourable mosquito habitats. This study evaluates environmental and design factors influencing mosquito larvae abundance in two contrasting wetland systems: the USM Engineering Campus Wetland and the Putrajaya Wetland Park. Field data included larvae counts, physico-chemical water parameters, hydrological characteristics, and habitat features. Statistical analyses comprising correlation tests, regression modelling, and non-parametric comparisons were performed to identify significant predictors of mosquito abundance. The Water Quality Index (WQI) showed a weak and non-significant relationship with mosquito larvae density at both study sites (USM: ρ = 0.072, p = 0.764; Putrajaya: r = 0.052, p = 0.811), likely due to its narrow range (70–85, Class II) that does not capture ecological responses under poorer water quality conditions. In contrast, several individual water quality parameters were significant predictors. In the USM wetland, higher Biochemical Oxygen Demand (BOD) and lower water temperature were associated with increased mosquito abundance. In the Putrajaya wetland, elevated Ammonia Nitrogen (AN) significantly correlated with higher larvae counts, indicating nutrient-enriched conditions that support mosquito breeding. Hydrological design factors also influenced larvae distribution. Higher Average Bank Flow Velocity (ABFV) in the USM wetland reduced mosquito density, while the more stable hydrological regime in Putrajaya favoured greater mosquito productivity. Overall, the study concludes that mosquito breeding in constructed wetlands is driven more strongly by specific water quality parameters and hydrological conditions than by the composite WQI. Key predictors including BOD, AN, water temperature, and flow velocity highlight critical design and management considerations for reducing mosquito breeding risks. These findings provide practical guidance for integrating public health considerations into constructed wetland planning and operation, supporting the development of environmentally effective yet mosquito-resilient wetland systems.
- PublicationA study on the effect of spur dike Design on sandbar retention ratio in Open channel.(2025-05)In urban settings, large concrete drainage channels often experience water stagnation and waste accumulation during dry seasons. As a nature-based solution, the spur dike and the sandbar offer multiple ecological and hydraulic benefits. By locally narrowing the channel width, the spur dike increases water depth and flow velocity, thereby reducing stagnant water. Additionally, the sandbar contributes to water quality improvement and provides habitats for plants, animals, and microorganisms, promoting ecological restoration. A low-profile spur dike can effectively trap sediment to form a sandbar while also preventing its erosion, without impeding flow during high-discharge events.This study integrates scaled physical modeling with numerical simulations to validate the scouring processes of sandbars between spur dikes in non-movable bed condition. The non-movable bed simulates the conditions of a concrete-lined drainage channel. The results confirm that the numerical approach accurately replicates the erosion and deposition dynamics. Based on this validation, the study further investigates the influence of five key aspects: spur dike length, interval, angle, shape, and arrangement, on the sandbar retention ratio. Previous literature has examined the effects of spur dike shape and angle on the riverbed in the context of mobile bed conditions. In contrast, this study shows that under subcritical flow conditions with unsubmerged spur dikes on a non-movable bed, the T-shaped spur dike and the one oriented perpendicular or slightly inclined upstream to the flow provide the most effective sandbar protection. This is similar to the findings in previous literature. Regarding the other aspects that have been less studied, the findings indicate that a longer spur dike, a wider interval, and a depression arrangement all contribute to higher sandbar retention ratio. It is important to note that while a longer spur dike may increase scouring in movable beds, it enhances sandbar protection in non movable condition. However, excessive length may lead to raised upstream water levels and should be addressed carefully in practical applications.In conclusion, under subcritical flow and non-submerged, non-mobile bed conditions, a sandbar with a larger initial volume, an upstream-facing spur dike that diffuses incoming flow, and the presence of a low-velocity buffer zone (such as in the case of the depression arrangement), are all beneficial for sandbar preservation. The design of the spur dike should be adapted to site-specific conditions to fully utilize the ecological and hydraulic functions of sandbars in environmental restoration.
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- ItemPerak Shimbun May 21 2605 (21 May 1945).(1945-05-21)
- ItemEffects Of Glucono-Delta-Lactone (Gdl) On Pasting, Rheological And Textural Properties Of Waxy Rice Starch(Universiti Sains Malaysia, 2020-07)Glucono-delta lactone (GDL) is a weak acid and it is easily soluble in water. Research focused on addition of GDL on starch is very limited and to the best of our knowledge it has not been reported in the literature. Thus, the current study has been conducted to study the effects of GDL addition on pasting, rheological and textural properties of waxy rice starch. Pasting properties were analysed using rapid visco analyser (RVA). The addition of GDL solution was found to increase the peak viscosity and breakdown viscosity of the waxy rice paste. When the GDL concentration increased, it was found that trough viscosity, final viscosity and setback viscosity decreased progressively. Next, steady-state flow and oscillatory analyses were carried out to study the rheological properties of waxy rice starch. For steady-state flow analysis, when shear rate increased, addition of GDL solution decreased the viscosity of the waxy rice paste and also resulted in a decreased of thixotropic value. The waxy rice pastes exhibited a non-Newtonian and shear thinning flow behaviour For oscillatory analysis, G’ and G’’ values increased with increasing frequency, and G’ was much higher than G’’ at all frequency values in increasing GDL solution. From the back extrusion analysis, it was found that waxy rice paste prepared with 0.03% w/v GDL solution resulted in a progressive decreased in firmness, consistency, cohesiveness and index of viscosity over the storage. It showed that waxy rice flour pasted with GDL exhibited less tendency of retrogradation.
- PublicationComplexity reduction in integer klt for lossless hyperspectral image compression(2022-08-01)The research presented in this thesis is concerned about complexity reduction in Integer KLT algorithm for lossless hyperspectral image compression. The Integer KLT is addressed because it outperforms other algorithms in decorrelating the spectral component in hyperspectral images. At the same it has it’s own drawbacks. Integer KLT has many process which makes the algorithm to be more complex and time consuming. The goals of this study are to reduce the execution time and complexity of the Integer KLT algorithm by modifying the code, as well as to implement and compare the performance of the Integer KLT algorithm on the Raspberry Pi 4 and the desktop. Two method were used to reduce the execution time which are simplifying the mathematical expression and removing tiling method. The execution time for the compression of the AVIRIS and Hyperion hyperspectral image datasets improve with the following method. Next, a different platform was used to implement the Integer KLT algorithm to evaluate the performance. From the following method, Desktop’s Windows shows a superior performance when compared to Raspberry Pi 4. This result was influenced by number of cores and RAM respectively of each hardware. The window’s desktop has a high power system with a processor of eight cores and 16 logical processors compared raspberry pi 4 where it only has four cores. This research justifies that an hardware specification and the complexity of coding language, highly influenced the execution time of a program.
- PublicationUnderstanding the role of nnav1.5 in breast cancer via sirna approach(2025-02)Neonatal Nav1.5 (nNav1.5) plays a crucial role in the development and spread of breast cancer. This work highlights its potential as a biomarker and treatment target. The hallmarks of breast cancer, a cancer that is common around the world, are unchecked cell growth and metastasis. Targeted therapies are needed since metastasis is responsible for around 90% of cancer-related fatalities, despite the advancements in early identification and therapy. The study explored the molecular mechanisms underlying nNav1.5's role in the invasive property of breast cancer. In MDA-MB-231 cells, siRNA-mediated knockdown was used to assess its effect of nNav1.5 mRNA expression and metastatic behaviour, cell motility. Previous research results showed that nNav1.5 is substantially overexpressed in metastatic breast cancer cells relative to non-metastatic cells, which is associated with increased invasive and migratory capabilities. In this study, the potential role of nNav1.5 in the development of metastases was further supported by the significant decrease in cancer cell motility which siRNA-mediated silencing of nNav1.5. This study also supports nNav1.5 expression as a useful prognostic indicator for aggressive breast cancer subtypes, the triple-negative breast cancer. A solid basis for future research aiming at incorporating nNav1.5-targeted tactics into precision medicine frameworks is established by this work, which also contributes to our understanding of metastatic biology. These results could greatly improve patient survival and breast cancer care by tackling the crucial problem of metastasis
- ItemThe Analysis Of The Relationship Between Personality Types, Reflectivity, And Self-Efficacy Of EFL Teachers In Private Language Schools In Iran(2012-01)The study was conducted to explore the relationship between Iranian English teachers‟ reflection levels, their self-efficacy, and their personality types. The purpose of this research is to find out if personality types of Iranian English teachers is related to their reflection level and/or self-efficacy levels, and hence to explore if teachers‟ self is a determining factor in their teaching practices. An additional aim of the study is to investigate if teachers‟ self-efficacy and their reflection levels are related, in order to find out if involvement in reflective practices makes teachers more effective. Establishment of a relationship between teacher personality on the one hand and reflective teaching and self-efficacy on the other, allows teacher educators to select and train teachers more effectively. Three instruments were employed to quantify the three constructs. Myers-Briggs Type Indicator (MBTI) was used to determine the participants‟ personality types. To measure their reflection levels, English Language Teaching Reflection Inventory (ELTRI) was used. The participants‟ self-efficacy was measured by Teachers‟ Sense of Efficacy Scale (TSES). First, MBTI was circulated among the randomly selected subjects to determine their personality types. Next, the subjects were randomly divided into experimental and control groups. In the pre-test phase, ELTRI (English Language Teacher Reflection Inventory) and TSES (Teachers‟ Sense of Efficacy Scale), which measure dependent variables of the study (teacher overall reflectivity and teacher overall self-efficacy), were distributed in both groups to measure their reflection and self-efficacy levels before the treatment. As the treatment, practical reflection (independent variable) was promoted in the experimental group. In the post-test phase, both control and experimental groups received ELTRI and TSES simultaneously in order to discover any possible changes. SPSS 16 was used for data analysis to answer the research questions. While the findings of this study confirmed a positive relationship between teacher reflection and self-efficacy, no significant relationship could be established between teachers‟ personality types and their levels of reflection. Teachers‟ self-efficacy and their personality types, however, were found related.