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In general, landslides in Malaysia mostly occurred during northeast and southwest periods, two monsoonal systems that bring heavy rain. As the consequence, most landslide occurrences were induced by rainfall. This paper reports the effect of monsoonal-related geospatial data in landslide hazard modeling in Cameron Highlands, Malaysia, using Geographic Information System (GIS). Land surface temperature (LST) data was selected as the monsoonal rainfall footprints on the land surface. Four LST maps were derived from Landsat 7 thermal band acquired at peaks of dry and rainy seasons in 2001. The landslide factors chosen from topography map were slope, slope aspect, curvature, elevation, land use, proximity to road, and river/lake; while from geology map were lithology and proximity to lineament. Landslide characteristics were extracted by crossing between the landslide sites of Cameron Highlands and landslide factors. Using which, the weighting system was derived. Each landslide factors were divided into five subcategories. The highest weight values were assigned to those having the highest number of landslide occurrences. Weighted overlay was used as GIS operator to generate landslide hazard maps. GIS analysis was performed in two modes: (1) static mode, using all factors except LST data; (2) dynamic mode, using all factors including multi-temporal LST data. The effect of addition of LST maps was evaluated. The final landslide hazard maps were divided into five categories: very high risk, high risk, moderate, low risk, and very low risk. From verification process using landslide map, the landslide model can predict back about 13–16% very high risk sites and 70–93% of very high risk and high risk combined together. It was observed however that inclusion of LST maps does not necessarily increase the accuracy of the landslide model to predict landslide sites.  相似文献   
2.
The force analogy method(FAM) is considered as one of the most time-saving and cost-efficient methods for analyzing frames. Through a set of assumptions and restoring forces, FAM analyzes nonlinear frames responses through Hooke's law. This study evaluates the effect of element type on FAM through numerical and experimental tests. The conventional Euler Bernoulli(EB) element is replaced by the Timoshenko(TS) beam-column element and the results are interpreted and compared with experimental findings. Three experimental tests were conducted for benchmarking and comparison purposes via 2 D aluminum frames. The results indicated that during the analysis, when the frame response is in the linear region, there is no difference between the element types in the response of the frames. When the frame entered the plastic region, the frames which were analyzed by the TS element revealed closer responses to the experimental outcomes. The gap between the results of the frame which was analyzed by EB and TS enlarged especially when the frame experienced a sharp or huge rotation of more than 0.2 rad. The final recorded deformations based on the TS element revealed an accuracy between 98.05% to 98.65%, while the EB element showed 14.66% to 45.14% for rotations of more than 0.2 rad at plastic hinge locations(PHLs).  相似文献   
3.
Indonesia is located in the Pacific Ring of Fire and situated at the joining point of four major world tectonic plates. Regions of Indonesia are highly prone to various natural hazards such as earthquakes, tsunamis and volcanic eruptions. Some recent major natural hazard events are the 2004 tsunami in Aceh and Nias and the 2010 Mount Merapi volcanic eruptions in Central Java. In parallel with advancement in knowledge of the existing hazards, the importance of social aspects of vulnerability in mitigating natural hazards has been acknowledged by the Indonesian government. However, to date, there is no institutionalized effort for assessing social vulnerability to natural hazards that would cover all the districts of Indonesia. Accordingly, no comprehensive profile of social vulnerability is available as basis information for developing strategies to prevent larger risk and losses and reduce vulnerability of communities in Indonesia. Only a few studies have been conducted in Indonesia on this field. This study attempts to fill this gap by quantifying the social vulnerability of Indonesian districts to natural hazards, determining its driving factors and mapping its variations. The social vulnerability index (SoVI) approach is utilized in this study. Three main driving factors affecting social vulnerability in Indonesia are found: ‘socioeconomic status and infrastructure,’ ‘gender, age and population growth’ and ‘family structure.’ The combination of SoVI with thematic map utilizing ArcView GIS can be used to identify districts with relative high social vulnerability level. The results can support the prevention, mitigation, preparedness, response and recovery programs of the impacts of natural hazards in Indonesia.  相似文献   
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Submarine slides are one of the most complex geotechnical problems causing serious damages to the seabed environment. Damages may lead to imminent destruction of offshore facilities such as platform and subsea pipeline. Mud sediment was the most susceptible of subsea material involved in the event. The completeness of field investigation is very limited; therefore, laboratory experiment is implemented in view of modeling the dynamics movement at the time of submarine slides occurs. The current experiment was conducted by generating the mudflow in water ambient over an inclined base to observe the flow-front structures of the mudflow. As facility to investigate the drag force exerted by mudflow, additional pipe model was positioned at certain flow distance. Mud models were prepared from mixtures of 10–35 % by weight of kaolin and water. Mudflow observations were limited to 3.5-m run-out distance with an exemption for 35 % KCC since this percentage stopped flow at 2.3-m flow distance. The role analysis of destructive flow was developed by the determination of drag force coefficient exerted by mudflow incorporating the Reynolds number. Velocity analysis indicates that all flows were defined as initial flow since they have only one phase of slumping phase. With respect to head-flow height and densimetric Froude number, the general form of velocity propagation formula provided the satisfactorily results in tracing mudflow velocity observation of laboratory experiment. Furthermore, the higher percentage of KCC exerted the higher drag force than the lower one.  相似文献   
5.
Acta Geotechnica - During the construction of pavements, gravelly soil is used as the main material in the base and sub-base layers. Predicting the deformation behaviour of gravelly soil has been...  相似文献   
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