Earthquake-induced landslide prediction using back-propagation type artificial neural network: case study in northern Iran

Natural Hazards - Landslides can cause extensive damage, particularly those triggered by earthquakes. The current study used back propagation of an artificial neural network (ANN) to conduct risk...     

Context-aware abstraction and generalization of street networks: two cognitively engineered user-oriented approaches using network Voronoi diagrams

Generalization and spatial contextual awareness are prevalent concepts in geographic information systems. This study adopted a context-dependent user-centred network generalization method to create a sub-network for optimal route finding. The results show an increase in the number of preferred traversed edges. A route presentation approach is suggested that is based on cognitively engineered user-oriented abstraction of street network. Successive abstractions hierarchize the street network to create a hierarchical presentation structure. The route is projected onto one level in the structure. Then, instead of showing the exact route, the network Voronoi regions represented by the projected route are shown. Experience indicates that the suggested method is an efficient way of route presentation for a hierarchical regionalized structure of a human cognitive map.     

Multi-factor impact analysis of agricultural production in Bangladesh with climate change

Diverse vulnerabilities of Bangladesh's agricultural sector in 16 sub-regions are assessed using experiments designed to investigate climate impact factors in isolation and in combination. Climate information from a suite of global climate models (GCMs) is used to drive models assessing the agricultural impact of changes in temperature, precipitation, carbon dioxide concentrations, river floods, and sea level rise for the 2040–2069 period in comparison to a historical baseline. Using the multi-factor impacts analysis framework developed in Yu et al. (2010), this study provides new sub-regional vulnerability analyses and quantifies key uncertainties in climate and production. Rice (aman, boro, and aus seasons) and wheat production are simulated in each sub-region using the biophysical Crop Environment REsource Synthesis (CERES) models. These simulations are then combined with the MIKE BASIN hydrologic model for river floods in the Ganges-Brahmaputra-Meghna (GBM) Basins, and the MIKE21 Two-Dimensional Estuary Model to determine coastal inundation under conditions of higher mean sea level. The impacts of each factor depend on GCM configurations, emissions pathways, sub-regions, and particular seasons and crops. Temperature increases generally reduce production across all scenarios. Precipitation changes can have either a positive or a negative impact, with a high degree of uncertainty across GCMs. Carbon dioxide impacts on crop production are positive and depend on the emissions pathway. Increasing river flood areas reduce production in affected sub-regions. Precipitation uncertainties from different GCMs and emissions scenarios are reduced when integrated across the large GBM Basins’ hydrology. Agriculture in Southern Bangladesh is severely affected by sea level rise even when cyclonic surges are not fully considered, with impacts increasing under the higher emissions scenario.     

Magnetized Kelvin-Helmholtz instability in the presence of a radiation field

The purpose of this study is to analyze the dynamical role of a radiation field on the growth rate of the unstable Kelvin-Helmholtz (KH) perturbations. As a first step toward this purpose, the analyze is done in a general way, irrespective of applying the model to a specific astronomical system. The transition zone between the two layers of the fluid is ignored. Then, we perform a linear analysis and by imposing suitable boundary conditions and considering a radiation field, we obtain appropriate dispersion relation. Unstable modes are studied by solving the dispersion equation numerically, and then growth rates of them are obtained. By analyzing our dispersion relation, we show that for a wide range of the input parameters, the radiation field has a destabilizing effect on KH instability. In eruptions of the galaxies or supermassive stars, the radiation field is dynamically important and because of the enhanced KH growth rates in the presence of the radiation; these eruptions can inject more momentum and energy into their environment and excite more turbulent motions.     

CFD-Based Model for Estimating the River Bed Morphological Characteristics near Cylindrical Bridge Piers Due to Debris Accumulation

Water Resources - The scour and flow field patterns with accumulation of debris around bridge piers are completely different due to the reduction of flow area and the increase in depth average...     

Reliability analysis of the induced damage for single-hole rock blasting

Rock explosion has always been a complex problem because neither rock characteristics nor explosion waves could be accurately estimated. As such, this imposes a high uncertainty on deterministic methodologies available for damage prediction. In this paper, by defining two damage zones around the blast hole, including crushed and cracked zones, a first-order reliability analysis (FORM) was adopted to address this issue. For this purpose, FORM was used in a double-loop algorithm, where the inner loop was responsible for converging the FORM, and the outer loop was assigned to feed the inner loop with new cases. Using such nested-loop algorithm, the probability of exceedance was calculated for any desired damage zone radius. The maximum effect of the involved parameters on the failure probability induced around the blast hole was additionally studied using a parametric reliability analysis. The results showed that the radii for crushed and cracked zones are limited to 0.5 and 4.2?m, respectively, so that the probability of going beyond these limits is less than 1%. Moreover, the analyses of decoupled explosions showed that increasing the gap between the explosion charge and wall of the borehole could severely reduce the failure probability; however, the maximum effect of decoupling ratio occurs in the small range of radii between 0.3?mm and 2.35?m.     

Erratum to: Impacts of boreal hydroelectric reservoirs on seasonal climate and precipitation recycling as simulated by the CRCM5: a case study of the La Grande River watershed,Canada

Theoretical and Applied Climatology -     

Morphological and Phylogenetic Studies of a Copepod Species,Irodes parupenei Ho and Lin (2007), Infecting Parupeneus rubescens in Saudi Arabia

Dammam City is one of the gorgeous coastal areas in the Arabian Gulf of Saudi Arabia.The present study aimed to ex-amine one of the copepod species infecting the rosy goatfish that represents a highly consumed fish species by the local population in the Arabian Gulf.The copepod species isolated from the infected fish specimens belong to the family Taeniacanthidae and was iden-tified as Irodes parupenei Ho and Lin(2007),primarily based on its morphological,morphometric,and ultrastructural characteris-tics,especially the structures of the dorsal cephalic area,segmentation of the first antenna,the absence of the maxilliped claw in the fe-male specimens,and the setation and spinulation of the legs 2-4 for the adult females are of great significance in the taxonomic iden-tification.The 18S rRNA gene sequence was analyzed to ensure the precise identity and exact taxonomic status of the copepod species.The result showed that this copepod species belong to Taenicanthidae and closely related to Irodes sauridi(gb|JF781550.1)in the same taxon.More details on the specificity of the goatfish for Irodes species and identifying these parasitic taxa using molecular analysis are given in the present study.     

Three-parameter Radon transform in layered transversely isotropic media

Radon transform is a powerful tool with many applications in different stages of seismic data processing, because of its capability to focus seismic events in the transform domain. Three-parameter Radon transform can optimally focus and separate different seismic events, if its basis functions accurately match the events. In anisotropic media, the conventional hyperbolic or shifted hyperbolic basis functions lose their accuracy and cannot preserve data fidelity, especially at large offsets. To address this issue, we propose an accurate traveltime approximation for transversely isotropic media with vertical symmetry axis, and derive two versions of Radon basis functions, time-variant and time-invariant. A time-variant basis function can be used in time domain Radon transform algorithms while a time-invariant version can be used in, generally more efficient, frequency domain algorithms. Comparing the time-variant and time-invariant Radon transform by the proposed basis functions, the time-invariant version can better focus different seismic events; it is also more accurate, especially in presence of vertical heterogeneity. However, the proposed time-invariant basis functions are suitable for a specific type of layered anisotropic media, known as factorized media. We test the proposed methods and illustrate successful applications of them for trace interpolation and coherent noise attenuation.