Unmanned Aerial Vehicle (UAV)-Based for Slope Mapping and the Determination of Potential Slope Hazard

This paper discusses the applications of unmanned aerial vehicle (UAV) for geological mapping and the determination of cross-section of certain selected area. With the development of modern technology, the utilization of UAV to gather data for geological mapping can be considered as finest method as it is quick, reliable, precise, cost-effective and also easily to operate. High imagery quality is essential for the effectiveness and nature of normal mapping output such as Digital Surface Model (DSM) and also Ortho Images. The utilization of UAV to capture aerial photo helps to gather information from a normal area to an area which almost impossible to reach. With the data obtained by the UAV, it will later be processed in established software and the analysis of slope profile of certain selected study area will be done. From these analyses, the potential slope hazards which based on slope angles will be determined and considered as another interest of this study

Unmanned Aerial Vehicle (UAV)-Based for Slope Mapping and the Determination of Potential Slope Hazard

This paper discusses the applications of unmanned aerial vehicle (UAV) for slope mapping and the determination of potential slope hazard of three selected areas. With the development of modern technology, the utilization of UAV to gather data for slope mapping can be considered as finest method as it is quick, reliable, precise, cost-effective and also easily to operate. High imagery quality is essential for the effectiveness and nature of normal mapping output such as Digital Surface Model (DSM) and also Ortho Images. The utilization of UAV to capture aerial photo helps to gather information from a normal area to an area which almost impossible to reach. With the data obtained by the UAV, it will later process in established software and the analysis of slope profile of certain selected study areas will be done. Mapping using UAV was within the area of Pahang Matriculation College. Three slope area namely as Area 1, Area 2 and Area 3 are marked. Further analyses are conducted in these three areas to obtain the information of potential slope hazard based on slope angles. For Area 1, the slope is marked at the coordinate of (286136.265, 412066.821) to (286265.423, 411783.038). The slope angle between the two vertexes was 46.18° and considered as very steep slope. For Area 2, the slope is marked at the coordinate of (286054.203, 412021.343) to (285963.651, 411913.543). The slope angle between the two vertexes was 77.66° and considered as very steep slope. The slope at Area 3 is marked at the coordinate of (285847.833, 411775.762) to (285887.450, 411251.046). The slope angle between the two vertexes was 47.43° and considered as very steep slope. In conclusion, the use of UAV in geotechnical engineering proven to be very useful for slope mapping and determination of slope hazard based on slope angle

Dam Break Analysis of Batu Dam using Hec-Ras

Dam is commonly built in Malaysia as it provides benefits to the local population, mainly agricultural activity and flood control measures. However, its massive potential energy reservoir would impose risk of sudden containment breach leading to loss of life and property at inhabited downstream area. Simulations of dam break events are crucial to characterizing and reducing threats due to potential dam failures. In all post-event natural disasters, where most structural countermeasures have been lost, the preparation of a smoother evacuation mechanism remains the most critical prevention tool for successful evacuation planning. The urgency of designing an appropriate emergency planning is important in response to the disaster. To perform a dam break analysis, hydraulic modeling is required, which involves routing the inflow flood through a reservoir, estimating dam breach characteristics, and downstream routing/modeling issues. The HEC-RAS (River Analysis System) software is commonly used for dam break studies. The software provides information on how to perform a dam break analysis, including the unique hydraulic modeling aspects that are required. Batu dam has the highest percentage of the population at risk (PAR) and most likely exposed to the flood disaster due to dam break. From flood boundary maps, it was estimated that 78% of residential areas would be affected if a dam break disaster occurs. From the simulation, the maximum depth can reach up to 18m with an estimated flow speed between 0.2 – 3m/s. At these depth and flow speed, people may lose strength and unable to control themselves in flood and would cause death and injury. Flood arrival time took 15 to 22 hours for flooding to arrive downstream with a maximum flood depth of 5.07m at Persiaran Jasa Utama and the highest depth of 12.62m at Kampung Baru Batu Caves with flood velocity between 1.60m/s to 1.46m/s. Analysis and simulation of embankment dam breach events and the resulting floods are crucial for distinguishing and mitigating dangers from potential dam failures. Accurate forecast of inundation levels and the time of flood wave arrival at downstream key places is required for the development of effective emergency response plans

Influence of burrow holes in residual soil slope infiltration

Infiltration rate is important factors in the rainfall induced slope failure. The infiltration of water into residual soil was govern by rainfall intensity and also saturated permeability of soil. The existing of burrow holes has proven increases the permeability of the soil with increase in number of burrow holes. Therefore, it is very important to study the effect of burrow holes in residual soil slope and its effect in infiltration rate. The modified constant head permeability was done to study effect of burrow holes in residual soil. Then, the infiltration test was done to study the infiltration rate of residual soil with existing of burrow holes. The result from modified permeability shows that permeability of residual soil increases from 5 x 10-7 m/s to 1.14 x 10-3 m/s for different area of burrow holes. The result from infiltration test proven that when q/ksat greater than 1 the runoff was occurs. Meanwhile, when q/ksat less than 1 infiltration was occurs. The result also indicates that the smaller ratio between of resq/ksat, the faster the infiltration of water into the soil. Ngee Leh, F.L.

Granite Exploration by using Electrical Resistivity Imaging (ERI): A Case Study in Johor

Electrical Resistivity Imaging (ERI) is a tool used in near surface geophysical surveys by flowing an electric current through electrodes that were injected into the ground. The usage of electrical resistivity imaging (ERI) method dominated by geophysicist has increased tremendously in geotechnical engineering application owing to the efficiency and effectiveness of the method in term of time, cost and also data coverage. The survey performed with respect to the particular reference to ERI in determining the granite rock underneath the ground. There were seven (7) lines of ERI performed at the study area by using ABEM Terrameter LS 2 set of equipment based on Schlumberger protocol. Six (6) boreholes were also drilled to obtain engineering properties of rock at the study area. In order to develop the relationship between resistivity and engineering properties, a comparison between borehole field test result and the resistivity value were made. Results from the ERT indicated the presence of zones with high resistivity values identified as overburden soil, fractured granite and solid granite. The findings of this study also showed that the electrical resistivity imaging coupled with borehole drillings were applicable tools for the determination of the granite rock underneath the ground via subsurface profiles and such as depth of overburden soil and engineering properties of soil

Physico-mechanical characteristics of tropical granite boulders in weathered heterogeneous zones for geotechnical design purposes

The presence of isolated or clustered granite boulders in tropical weathered masses commonly formed a very thick heterogeneous zone in weathering Zone 3 to 5. The boulders with various characteristics are always misinterpreted during the geotechnical design process due to being poorly understood and studied. This study aims to determine the physico-mechanical characteristics of boulders in different weathering zones for design purposes. The parameters studied include boulder types, porosity, density, durability, point load and uniaxial compressive strength. Results revealed boulders in weathering Zone 3, 4 and 5 can be classified into Type A, B and C, respectively. These boulders have significant differences in physical and mechanical properties. The boulders in Zone 4 and 5 consists of corestone, ringlets and saprolites and the boulders in Zone 3 have no ringlets. Corestones have the highest durability, point load and compressibility strength with a median of 94.5%, 7.80 MPa and 187.07 MPa, respectively. The ringlets possess the highest porosity range of 23.3%–31.3% compared with saprolite. Saprolite in Zone 5 has the lowest durability, point load and compressive strength with respectively less than 7%, 0.22 MPa and 1 MPa. The various characteristics of the boulders in different weathering zones could influence the geotechnical design model

An overview of burst, buckling, durability and corrosion analysis of lightweight FRP composite pipes and their applicability

© 2019 Elsevier Ltd. All rights reserved.The main aim of this review article was to address the performance of filament wound fibre reinforced polymer (FRP) composite pipes and their critical properties, such as burst, buckling, durability and corrosion. The importance of process parameters concerning merits and demerits of the manufacturing methods was discussed for the better-quality performance. Burst analysis revealed that the winding angle of ±55° was observed to be optimum with minimum failure mechanisms, such as matrix cracking, whitening, leakage and fracture. The reduction of buckling effect was reported in case of lower hoop stress value in the hoop to axial stress ratio against axial, compression and torsion. A significant improvement in energy absorption was observed in the hybrid composite pipes with the effect of thermal treatment. However, the varying winding angle in FRP pipe fabrication was reported as an influencing factor affecting all the aforementioned properties. Almost 90% of the reviewed studies was done using E-glass/epoxy materials for the composite pipe production. By overcoming associated limitations, such as replacing synthetic materials, designing new material combinations and cost-benefit analysis, the production cost of the lightweight FRP composite pipes can be decreased for the real-time applications.Peer reviewe

Isoprene hotspots at the Western Coast of Antarctic Peninsula during MASEC′16

Isoprene (C5H8) plays an important role in the formation of surface ozone (O3) and the secondary organic aerosol (SOA) which contributed to the climate change. This study aims to determine hourly distribution of tropospheric isoprene over the Western Coast of Antarctic Peninsula (WCAP) during the Malaysian Antarctic Scientific Expedition Cruise 2016 (MASEC′16). In-situ measurements of isoprene were taken using a custom-built gas chromatography with photoionization detector, known as iDirac. Biological parameters such as chlorophyll a (chl-a) and particulate organic carbon (POC) were compared to the in-situ isoprene measurements. Significant positive correlation was observed between isoprene and POC concentrations (r2 = 0.67, p < 0.001), but not between isoprene and chl-a. The hotspots of isoprene over maritime Antarctic were then were investigated using NAME dispersion model reanalysis. Measurements showed that isoprene mixing ratio were the highest over region of King George Island, Deception Island and Booth Island with values of ∼5.0, ∼0.9 and ∼5.2 ppb, respectively. Backward trajectory analysis showed that air masses may have lifted the isoprene emitted by marine algae. We believe our findings provide valuable data set of isoprene estimation over the under sampled WCAP

Unmanned Aerial Vehicle (UAV)-Based for Slope Mapping and the Determination of Potential Slope Hazard

This paper discusses the applications of unmanned aerial vehicle (UAV) for geological mapping and the determination of cross-section of certain selected area. With the development of modern technology, the utilization of UAV to gather data for geological mapping can be considered as finest method as it is quick, reliable, precise, cost-effective and also easily to operate. High imagery quality is essential for the effectiveness and nature of normal mapping output such as Digital Surface Model (DSM) and also Ortho Images. The utilization of UAV to capture aerial photo helps to gather information from a normal area to an area which almost impossible to reach. With the data obtained by the UAV, it will later be processed in established software and the analysis of slope profile of certain selected study area will be done. From these analyses, the potential slope hazards which based on slope angles will be determined and considered as another interest of this study

Rasch strategies for evaluating quality of the conceptions and alternative assessment survey (CETAS)

Due to society demand for educational development, education in Malaysia has begun to utilize alternative assessment approach in schools and universities. This study developed Conceptions and Alternative Assessment Survey (CETAS) to examine lecturers’ conceptions of assessment (AC) and their practice of alternative assessment (AAP). In order for CETAS to be useful, a pilot study was conducted to examine quality of items in using Rasch Analysis approach. A total of 38 lecturers involved in this study. After item analysis, this study found that four items, Item 7 (AC), Item 8 (AC), Item 16 (AAP) and Item 30 (AAP) did not meet the requirement of fit statistics analysis and local item dependency. Therefore, four items were deleted while other 58 are suitable to be used for measuring the intended constructs. In addition, the scale calibration analysis also revealed that Scale 3 (slightly disagree) was not well-functioning. Therefore, after consideration of analysis and expert review, Scale 3 was collapsed leaving CETAS with 5 scales. Nevertheless, CETAS has a good item and person reliability and can be used to examine lecturers’ conceptions of assessment and their practices of alternative assessment