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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.

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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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%.

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Bank instability as a result of flow fluctuations may lead to massive bank erosions and subsequent damage of adjacent properties. Continuous erosion process promotes change in the river morphology, sedimentation problems due to the presence of secondary currents and local scouring at piers downstream of the erosion point. Knowledge on the extent of erosion should facilitate river engineers to resolve issues on river training works and river sedimentation problems. A study has been carried out in the field to quantify the amount of eroded materials using erosion pins that were driven into the ground normal to the bank surface. The erosion pins consist of 6 mm diameter metal rods and 60 cm – 80 cm in length. A spatial variation profile for rates of erosion has been identified with units expressed in unit cm per day. The defining parameters for bank erosion rates have included near-bank velocity, Ub, water depth, Y, stream bank geometry and soil bearing capacity. Development of empirical equations had used multiple linear and nonlinear regression techniques to determine the significant erosion predictors. It takes into consideration the coefficient of determination (r-squared) and Root-mean square error (RSME) as determinants for best predictors. Accuracy of developed equations is measured using the discrepancy ratio, D.R. This is the ratio of predicted to measured erosion rate. Analysis suggest that the equation derived using polynomial function (order-2) gave better accuracy compared to the equation derived using linear and power functions. An accuracy of 75% has been obtained. Scatter plots of the predicted to the measured erosion rates have shown to be between 0.5 – 2.0 within the line of good agreement.