Sediment transport models in river basins have been developed over the years for various temporal and spatial scales. However, yet few models have been reported for small-scale catchment and still under investigation by many researchers. In this paper, a distributed model based on process was presented for evaluating transportation of sediment in a small catchment scale. The integration of distributed hydrological and sediment model was developed for simulate the soil erosion and sedimentation processes in the catchment area located at Universiti Pertahanan Nasional Malaysia (UPNM). The finding prevailed that the simulation of suspended sediment load over a period of four years gave a good significant result with an average Nash–Sutcliffe Efficiency (NSE) and a Correlation Coefficient (r) were of 0.60 and 0.78, respectively. Moreover, sensitivity analysis revealed that the suspended sediment load in the UPNM catchment was influenced by soil detachability over land (Kf). Overall, the outputs from the present model can be taken as input to predict the soil erosion and sedimentation processes in a small-scale catchment, especially in Malaysia such as in the UPNM.

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Nowadays, UAV is preferred by experts since it is more affordable with reliable accuracy. However, debates on its accuracy draw worldwide attention in order to maintain the output’s quality. Flight altitude is one of the most debated issues of UAV employment due to various ground conditions. Thus, this study intends to investigate the effects of flight altitude towards the final output accuracy. In this study, three different flight altitudes (60m, 80m and 100m) were used to test the outputs accuracy within selected sites in UPNM campus by employing DJI Phantom 4 Pro V2.0 drone. Orthophotos and Digital Surface Model (DSM) of the selected sites were then generated using Pix4D Mapper Software. On-screen measurements of selected features within the selected sites were taken and compared with the actual measurements obtained on grounds. Later, these outputs were used to generate contours using ArcGIS software. The generated contours were compared with available as-built plan. The results were examined qualitatively and quantitatively. From this study, it is found that the mean variance values on flat surface using different flight elevation were 0.86m, 0.99m and 1.16m for 60m, 80m and 100m respectively. Whereas, the mean variance values on hilly surface were 6.95m, 4.35m and 4.3m for 60m, 80m and 100m. On flat surfaces, 60m flight altitude was the best height to be used for UAV mapping. However, for hilly surfaces, 100m flight altitude was the best height to be used. This contrast may due to the lower overlapping images in 60m flight altitude image capture. From the study also, it is found that the accuracy of UAV mapping on hilly surfaces tends to be lower than flat surfaces. This called for further studies to identify the best measures to reduce the errors resulted by extreme ground characteristics.

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Slope failure is a natural disaster that involves the movement of ground and rock under the influence of gravity. There are several factors influencing slope stability, including the excessive surcharge load imposed on the top of the slope. This study performs slope stability analysis to evaluate the performance of a non-homogenous man-made slope constructed on the UPNM campus. The methodology of this research comprises two parts. The first part is laboratory test, and the second part is simulation work. The laboratory tests conducted to determine the soil properties are sieve analysis, permeability test, and direct shear test. The limit equilibrium method using the SlopeW software is employed to determine the effect of imposing a gradually increasing surcharge load on the man-made slope from a varying distance. The value of Factor of Safety (FOS) and critical slip surface formation obtained using SlopeW were used to determine the maximum load carrying-capacity before failure. The results showed that the FOS decreased with an increasing surcharge load. However, the FOS increased as the distance of the load increase. Further analysis was carried out to enhance the stability of the slope. By reducing 40% of slope height, the stability of slope is increased to 44%. It is also suggested that no activity or development should be carried out on the slope crest to prevent slope failure occurrence in the future.