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Student-centered learning (SCL) is one of the teaching methods commonly used nowadays as it encourages the active participation and engagement of students in the classroom, especially for the engineering theoretical subject. This study is aimed to examine the factors of students’ involvement and participation towards the SCL Teaching Method in terms of the activities, benefits, problems, and limitations of student involvement. The quantitative data are obtained from the responses of students that enroll in an engineering theoretical subject in the Universiti Teknologi MARA (UiTM) Pahang Civil Engineering Diploma Program. These questionnaires were being classified into five major factors that are the formation of group studies for SCL activities, activities conducted for SCL teaching method, benefits that they gain from SCL method, problems that they encounter during SCL, and suggestions for student improvement towards the activity SCL session. The collected data were analyzed quantitatively by using the percentage and mean method in SPSS computer software. The Relative Importance Index (RII) system was used to quantify the relative importance of involvement factors. This study revealed three main factors affecting the participation and engagement of students in the classroom. This study has an important contribution to help academicians to improve and enhance their teaching method to achieve the objective of the SCL method in the future.

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Bank erosion is commonly associated with river meandering initiation and development, through width adjustment and planform evolution. It consists of two types of erosion processes; basal erosion due to fluvial hydraulic force and bank failure under the influence of gravity. Most of the studies only focused on one factor rather than integrating both factors. Evidences of previous works have shown integration between both processes of fluvial hydraulic force and bank failure. Bank failure seldom treated as a probabilistic phenomenon without assessing the physical characteristics and the geotechnical aspects of the bank. Thus, the objective of this paper is to investigate factors governing streambank erosion process and to perform a dimensional analysis considering the physical characteristics of both processes namely fluvial erosion and mass failure and their interaction.

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Assessing the effects of rainfall patterns on runoff, sediment, nutrients under variation of rainfall pattern are significant in the quantification of sediment transported by overland flow. Previous experimental and field works studied that sediment transport is influenced by hydraulic properties of flow, physical properties of soil and surface characteristics. This study aims at determining the effect of rainfall patterns on surface runoff, sediment loss and nutrient loss. Experiments were carried out using four rainfall patterns, namely Pattern A (uniform-type: 8-8-8 l/min), Pattern B (increasing-type: 7-8-9 l/min), Pattern C (increasing-decreasing-type: 7-9-8 l/min) and Pattern D (decreasing-type: 9-8-7 l/min) with the changes of intensity every 30 minutes that gives total rainfall duration of 90 minutes for each pattern. The simulation was performed in three repetitions. The average total runoff produced was 668.65, 701.40, 699.10, and 722.63 liters, for rainfall patterns A, B, C, and D, respectively. The trend of runoff generated was influenced by the rainfall patterns, Pattern D generated the highest amount of runoff meanwhile Pattern A generated the lowest. For total suspended sediment concentrations, the mean value among every three repetitions of rainfall pattern resulted as 14,518.88, 13,732.73, 8,011.71 and 19,918.50 mg/l for patterns A, B, C, and D, respectively Pattern D contributed to the highest amount of sediment accumulated whereby Pattern C generated the lowest sediment despite the trend showed a different approach than the other 3 patterns. In nutrient concentrations, the determined total losses for ammonia nitrogen were 3.986, 2.891, 3.504, and 4.601g; nitrate nitrogen were 3.934, 2.665, 4.008, and 3.259g; phosphorus were 1.346, 0.222, 0.207, and 0.679g, for patterns A, B, C, and D, respectively. In general, rainfall pattern does have a significant impact on the trend of nutrient losses, where the trend shows that higher concentrations at the start and eventually lowered through the end, but Pattern D as compared to other patterns resulted in a more severe nutrient loss. For the affected area of the soil movement process, the calculated means of the affected area are 79.60, 68.70, 72.43, and 64.97% for patterns A, B, C, and D respectively. The lowest mean of the affected area is contributed by Pattern D and the highest by Pattern A.

Sediment removed in the detachment process is transported by overland flow. Previous experimental and field works studied that sediment transport is influenced by hydraulic properties of flow, physical properties of soil, and surface characteristics. Several equations in predicting sediment transport have been developed from previous research. The objective of this paper was to establish the selected parameters that contribute to the sediment transport capacity in overland flow conditions under different rainfall pattern conditions and to evaluate their significance. The establishment of independent variables was performed using the dimensional analysis approach that is Buckingham’s π theorem. The final results obtained are a series of independent parameters; the Reynolds number (Re), dimensionless rainfall parameter iLν, hydraulic characteristics QLν that related to the dependent parameters; and dimensionless sediment transport qsρv. The relationship indicates that 63.6% to 72.44% of the variance in the independent parameters is in relation to the dependent parameter. From the iteration method, the estimation of constant and regression coefficient values is presented in the form of the general formula for linear and nonlinear model equations. The linear and nonlinear model equations have the highest model accuracy of 93.1% and 81.5%, respectively. However, the nonlinear model equation has the higher discrepancy ratio of 54.9%.

This study aims to develop a streambank erosion prediction model using Artificial Neural Network Autoregressive Exogenous (ANNARX) for natural channels. ANNARX is one type of ANN models and it is a supervised network that trains spasmodic data sets. Field data of 494 data extracted from two (2) rivers in Selangor, namely Sg. Bernam and Sg. Lui were used in the training and testing phases. Total of eleven (11) independent variables are used as input variables in the input layer and the ratio between erosion rates, ? to the near-bank velocity, Ub as the output variable. The functional relationships were derived using Buckingham Pi Theorem in the dimensional analysis. A supervised learning technique was employed and the target output is streambank erosion rates, ?b. The established models were validated to assess their performances in predicting the rates of streambank erosion using 176 data. Validation of the newly developed streambank erosion rates equation has been conducted using data obtained from this study. The performance of the derived model was tested using discrepancy ratio and graphical analysis. Discrepancy ratio (DR) is the ratio of predicted values to the measured values and these values are deemed accurate if the data lie between 0.5 to 2.0 limit. Total of 8 models have been developed in the predictive model. Analysis confirmed that models developed using ANNARX are capable to achieve coefficient correlations (r-squared) values above 0.9 and successfully predict the measured data at accuracy above 90%.