Assessment of risks of tunneling project in Iran using artificial bee colony algorithm

The soft computing techniques have been widely applied to model and analyze the complex and uncertain problems. This paper aims to develop a novel model for the risk assessment of tunneling projects using artificial bee colony algorithm. To this end, the risk of the second part of the Emamzade Hashem tunnel was assessed and analyzed in seven sections after testing geotechnical characteristics. Five geotechnical and hydrological properties of study zone are considered for the clustering of geological units in front of tunneling project including length of tunnel, uniaxial compressive strength, rock mass rating, tunneling index Q, density and underground water condition. These sections were classified in two low-risk and high-risk groups based on their geotechnical characteristics and using clustering technique. It was resulted that three sections with lithologies Durood Formation, Mobarak Formation, and Ruteh Formation are placed in the high risk group and the other sections with lithologies Baroot Formation, Elika Formation, Dacite tuff of Eocene, and Shear Tuff, and Lava Eocene are placed in the low risk group. In addition, the underground water condition and density with 0.722 and 1 Euclidean distances have the highest and lowest impacts in the high risk group, respectively. Therefore, comparing the obtained results of modelling and actual excavation data demonstrated that this technique can be applied as a powerful tool for modeling risks of tunnel and underground constructions

Rockfall threatening cumae archeological site fruition (Phlegraean fields park—naples)

Natural hazards threaten many archaeological sites in the world; therefore, susceptibility analysis is essential to reduce their impacts and support site fruition by visitors. In this paper, rockfall susceptibility analysis of the western slope of the Cumae Mount in the Cumae Archaeological Site (Phlegraean Fields, Naples), already affected by rockfall events, is described as support to a management plan for fruition and site conservation. Being the first Greek settlement in southern Italy, the site has great historical importance and offers unique historical elements such as the Cumaean Sibyl’s Cave. The analysis began with a 3D modeling of the slope through digital terrestrial photogrammetry, which forms a basis for a geomechanical analysis. Digital discontinuity measurements and cluster analysis provide data for kinematic analysis, which pointed out the planar, wedge and toppling failure potential. Subsequently, a propagation-based susceptibility analysis was completed into a GIS environment: it shows that most of the western sector of the site is susceptible to rockfall, including the access course, a segment of the Cumana Railroad and its local station. The work highlights the need for specific mitigation measures to increase visitor safety and the efficacy of filed-based digital reconstruction to support susceptibility analysis in rockfall prone areas

Remote Sensing of Natural Hazards

Each year, natural hazards such as earthquakes, cyclones, flooding, landslides, wildfires, avalanches, volcanic eruption, extreme temperatures, storm surges, drought, etc., result in widespread loss of life, livelihood, and critical infrastructure globally. With the unprecedented growth of the human population, largescale development activities, and changes to the natural environment, the frequency and intensity of extreme natural events and consequent impacts are expected to increase in the future.Technological interventions provide essential provisions for the prevention and mitigation of natural hazards. The data obtained through remote sensing systems with varied spatial, spectral, and temporal resolutions particularly provide prospects for furthering knowledge on spatiotemporal patterns and forecasting of natural hazards. The collection of data using earth observation systems has been valuable for alleviating the adverse effects of natural hazards, especially with their near real-time capabilities for tracking extreme natural events. Remote sensing systems from different platforms also serve as an important decision-support tool for devising response strategies, coordinating rescue operations, and making damage and loss estimations.With these in mind, this book seeks original contributions to the advanced applications of remote sensing and geographic information systems (GIS) techniques in understanding various dimensions of natural hazards through new theory, data products, and robust approaches

A novel rule-based approach in mapping landslide susceptibility

© 2019 by the authors. Licensee MDPI, Basel, Switzerland. Despite recent advances in developing landslide susceptibility mapping (LSM) techniques, resultant maps are often not transparent, and susceptibility rules are barely made explicit. This weakens the proper understanding of conditioning criteria involved in shaping landslide events at the local scale. Further, a high level of subjectivity in re-classifying susceptibility scores into various classes often downgrades the quality of those maps. Here, we apply a novel rule-based system as an alternative approach for LSM. Therein, the initially assembled rules relate landslide-conditioning factors within individual rule-sets. This is implemented without the complication of applying logical or relational operators. To achieve this, first, Shannon entropy was employed to assess the priority order of landslide-conditioning factors and the uncertainty of each rule within the corresponding rule-sets. Next, the rule-level uncertainties were mapped and used to asses the reliability of the susceptibility map at the local scale (i.e., at pixel-level). A set of If-Then rules were applied to convert susceptibility values to susceptibility classes, where less level of subjectivity is guaranteed. In a case study of Northwest Tasmania in Australia, the performance of the proposed method was assessed by receiver operating characteristics’ area under the curve (AUC). Our method demonstrated promising performance with AUC of 0.934. This was a result of a transparent rule-based approach, where priorities and state/value of landslide-conditioning factors for each pixel were identified. In addition, the uncertainty of susceptibility rules can be readily accessed, interpreted, and replicated. The achieved results demonstrate that the proposed rule-based method is beneficial to derive insights into LSM processes

Image-Based Modeling of Bridges and Its Applications to Evaluating Resiliency of Transportation Networks

Modern urban areas are heavily dependent on transportation networks to sustain their economic life. Hence, when vital components of a regional network are disrupted, economic losses are inevitable. As evidenced by 1989, Loma Prieta and 1994, Northridge earthquakes, the seismic damages experienced by bridges alone result in extensive traffic delays and rerouting, not only hindering emergency response but also causing indirect economic losses that far surpass the direct cost of damage to infrastructure. Nevertheless, in many areas of the U.S., transportation networks lack the resilience required to sustain the potential demands of natural hazards. Traditional hazard assessment methods, in theory, provide the tools required for predicting the vulnerabilities associated with natural hazards. Nonetheless, due to their abstractions of the complex infrastructure and the coupled regional behavior, they often fall short of that expectation. This study proposes a semi-automated image-based model generation framework for producing structure-specific models and fragility functions of bridges. The framework effectively fuses geometric and semantic information extracted from Google Street View images with centerline curve geometry, surface topology, and various relevant metadata to construct extremely accurate geometric representations of bridges. Then, using class statistics available in the literature for bridge structural properties, the framework generates structural models. Both the performance of the geometry extraction procedure and the structural modeling method proposed here are validated by comparison against the structural model of a real-life bridge developed based on as-built drawings.In principle, these models can be utilized to assess physical damage for any type of hazard, but in this study, the focus is limited to seismic applications. Thus to relate the damage resulting from seismic demands from ground shaking, bridge-specific fragility functions are developed for 100 bridge structures in the immediate surroundings of Ports of Los Angeles and Long Beach. Using these fragility curves, the physical damage resulting from a magnitude 7.3 scenario earthquake on Palos Verdes fault is predicted. Subsequently, the effects of the bridge infrastructure damage to the transportation patterns in the Los Angeles metropolitan area are investigated in terms of various resilience metrics

Impact of DEM-derived factors and analytical hierarchy process on landslide susceptibility mapping in the region of Rożnów Lake, Poland

El artículo analiza las desigualdades que se gestan y reproducen en las trayectorias educativas universitarias de los jóvenes ecuatorianos en España y Ecuador en el contexto de la crisis, centrándose en las estrategias vinculadas a la movilidad de estos jóvenes y sus familias y el papel que juegan las políticas públicas. Se examinan los recorridos de tres grupos de universitarios: las hijas e hijos de la migración de los 2000, los retornados a Ecuador y los que llegan a España gracias a las ayudas del gobierno ecuatoriano para realizar postgrados. Se parte de una metodología fundamentalmente cualitativa basada en entrevistas, grupos de discusión y una encuesta a los participantes desde España de la prueba de acceso para integrarse en universidades públicas ecuatorianas. Los hallazgos ponen de relieve los capitales que manejan unos y otros y las restricciones sociales y económicas que encuentran. Mientras el primer grupo intenta mantenerse en la universidad, aun degradando sus expectativas, en el segundo grupo se advierte que la educación forma parte de en una estrategia más amplia que descansa en las redes transnacionales tejidas durante más de una década de migración hacia España. Finalmente, los del tercero han seguido trayectorias heterogéneas ascendentes que incluyen el desplazamiento.El artículo analiza las desigualdades que se gestan y reproducen en las trayectorias educativas universitarias de los jóvenes ecuatorianos en España y Ecuador en el contexto de la crisis, centrándose en las estrategias vinculadas a la movilidad de estos jóvenes y sus familias y el papel que juegan las políticas públicas. Se examinan los recorridos de tres grupos de universitarios: las hijas e hijos de la migración de los 2000, los retornados a Ecuador y los que llegan a España gracias a las ayudas del gobierno ecuatoriano para realizar postgrados. Se parte de una metodología fundamentalmente cualitativa basada en entrevistas, grupos de discusión y una encuesta a los participantes desde España de la prueba de acceso para integrarse en universidades públicas ecuatorianas. Los hallazgos ponen de relieve los capitales que manejan unos y otros y las restricciones sociales y económicas que encuentran. Mientras el primer grupo intenta mantenerse en la universidad, aun degradando sus expectativas, en el segundo grupo se advierte que la educación forma parte de en una estrategia más amplia que descansa en las redes transnacionales tejidas durante más de una década de migración hacia España. Finalmente, los del tercero han seguido trayectorias heterogéneas ascendentes que incluyen el desplazamiento.El artículo analiza las desigualdades que se gestan y reproducen en las trayectorias educativas universitarias de los jóvenes ecuatorianos en España y Ecuador en el contexto de la crisis, centrándose en las estrategias vinculadas a la movilidad de estos jóvenes y sus familias y el papel que juegan las políticas públicas. Se examinan los recorridos de tres grupos de universitarios: las hijas e hijos de la migración de los 2000, los retornados a Ecuador y los que llegan a España gracias a las ayudas del gobierno ecuatoriano para realizar postgrados. Se parte de una metodología fundamentalmente cualitativa basada en entrevistas, grupos de discusión y una encuesta a los participantes desde España de la prueba de acceso para integrarse en universidades públicas ecuatorianas. Los hallazgos ponen de relieve los capitales que manejan unos y otros y las restricciones sociales y económicas que encuentran. Mientras el primer grupo intenta mantenerse en la universidad, aun degradando sus expectativas, en el segundo grupo se advierte que la educación forma parte de en una estrategia más amplia que descansa en las redes transnacionales tejidas durante más de una década de migración hacia España. Finalmente, los del tercero han seguido trayectorias heterogéneas ascendentes que incluyen el desplazamiento.El artículo analiza las desigualdades que se gestan y reproducen en las trayectorias educativas universitarias de los jóvenes ecuatorianos en España y Ecuador en el contexto de la crisis, centrándose en las estrategias vinculadas a la movilidad de estos jóvenes y sus familias y el papel que juegan las políticas públicas. Se examinan los recorridos de tres grupos de universitarios: las hijas e hijos de la migración de los 2000, los retornados a Ecuador y los que llegan a España gracias a las ayudas del gobierno ecuatoriano para realizar postgrados. Se parte de una metodología fundamentalmente cualitativa basada en entrevistas, grupos de discusión y una encuesta a los participantes desde España de la prueba de acceso para integrarse en universidades públicas ecuatorianas. Los hallazgos ponen de relieve los capitales que manejan unos y otros y las restricciones sociales y económicas que encuentran. Mientras el primer grupo intenta mantenerse en la universidad, aun degradando sus expectativas, en el segundo grupo se advierte que la educación forma parte de en una estrategia más amplia que descansa en las redes transnacionales tejidas durante más de una década de migración hacia España. Finalmente, los del tercero han seguido trayectorias heterogéneas ascendentes que incluyen el desplazamiento.El artículo analiza las desigualdades que se gestan y reproducen en las trayectorias educativas universitarias de los jóvenes ecuatorianos en España y Ecuador en el contexto de la crisis, centrándose en las estrategias vinculadas a la movilidad de estos jóvenes y sus familias y el papel que juegan las políticas públicas. Se examinan los recorridos de tres grupos de universitarios: las hijas e hijos de la migración de los 2000, los retornados a Ecuador y los que llegan a España gracias a las ayudas del gobierno ecuatoriano para realizar postgrados. Se parte de una metodología fundamentalmente cualitativa basada en entrevistas, grupos de discusión y una encuesta a los participantes desde España de la prueba de acceso para integrarse en universidades públicas ecuatorianas. Los hallazgos ponen de relieve los capitales que manejan unos y otros y las restricciones sociales y económicas que encuentran. Mientras el primer grupo intenta mantenerse en la universidad, aun degradando sus expectativas, en el segundo grupo se advierte que la educación forma parte de en una estrategia más amplia que descansa en las redes transnacionales tejidas durante más de una década de migración hacia España. Finalmente, los del tercero han seguido trayectorias heterogéneas ascendentes que incluyen el desplazamiento.El artículo analiza las desigualdades que se gestan y reproducen en las trayectorias educativas universitarias de los jóvenes ecuatorianos en España y Ecuador en el contexto de la crisis, centrándose en las estrategias vinculadas a la movilidad de estos jóvenes y sus familias y el papel que juegan las políticas públicas. Se examinan los recorridos de tres grupos de universitarios: las hijas e hijos de la migración de los 2000, los retornados a Ecuador y los que llegan a España gracias a las ayudas del gobierno ecuatoriano para realizar postgrados. Se parte de una metodología fundamentalmente cualitativa basada en entrevistas, grupos de discusión y una encuesta a los participantes desde España de la prueba de acceso para integrarse en universidades públicas ecuatorianas. Los hallazgos ponen de relieve los capitales que manejan unos y otros y las restricciones sociales y económicas que encuentran. Mientras el primer grupo intenta mantenerse en la universidad, aun degradando sus expectativas, en el segundo grupo se advierte que la educación forma parte de en una estrategia más amplia que descansa en las redes transnacionales tejidas durante más de una década de migración hacia España. Finalmente, los del tercero han seguido trayectorias heterogéneas ascendentes que incluyen el desplazamiento.In the paper we analyze the inequalities that emerge from and are reproduced in Ecuadorian's higher education trajectories in the context of economic crises. We focus on the strategies that these youth and their families employ for social mobility as well as the role of public policy in these processes. We examine the trajectories of three groups: sons and daughters of the 2000 migration wave from Ecuador to Spain who study at universities in Spain, those who have returned to Ecuador for their studies, and Ecuadorians who move to Spain in order to carry out postgraduate studies, some of them funded by scholarships from the Ecuadorian government. The research project employed a qualitative methodology based on interviews, focus groups and a survey with Ecuadorians in Spain who took the entrance exam for admittance into Ecuador's public university system. Our findings highlight the varied forms of capitals that these diverse students employ, as well as the social and economic constraints that they encounter. In a period of economic crisis in Spain, the first group of students must often downgrade their expectations in order to continue their studies. Their experience contrasts starkly with Ecuadorians undertaking postgraduate studies in Spain, whose heterogenous trajectories are upwardly and geographically mobile. The case of the return university students to Ecuador shows us that education is inserted into a broader strategy that depends on transnational networks shaped over more than a decade of Ecuador-Spain migration

A Novel Hybrid Machine Learning-Based Model for Rockfall Source Identification in Presence of Other Landslide Types Using LiDAR and GIS

© 2019, King Abdulaziz University and Springer Nature Switzerland AG. Abstract: Rockfall is a common phenomenon in mountainous and hilly areas worldwide, including Malaysia. Rockfall source identification is a challenging task in rockfall hazard assessment. The difficulty rise when the area of interest has other landslide types with nearly similar controlling factors. Therefore, this research presented and assessed a hybrid model for rockfall source identification based on the stacking ensemble model of random forest (RF), artificial neural network, Naive Bayes (NB), and logistic regression in addition to Gaussian mixture model (GMM) using high-resolution airborne laser scanning data (LiDAR). GMM was adopted to automatically compute the thresholds of slope angle for various landslide types. Chi square was utilised to rank and select the conditioning factors for each landslide type. The best fit ensemble model (RF–NB) was then used to produce probability maps, which were used to conduct rockfall source identification in combination with the reclassified slope raster based on the thresholds obtained by the GMM. Next, landslide potential area was structured to reduce the sensitivity and the noise of the model to the variations in different conditioning factors for improving its computation performance. The accuracy assessment of the developed model indicates that the model can efficiently identify probable rockfall sources with receiver operating characteristic curve accuracies of 0.945 and 0.923 on validation and training datasets, respectively. In general, the proposed hybrid model is an effective model for rockfall source identification in the presence of other landslide types with a reasonable generalisation performance. Graphic Abstract: [Figure not available: see fulltext.]

Landslide riskscapes in the Colorado Front Range: a quantitative geospatial approach for modeling human-environment interactions

2021 Spring.Includes bibliographical references.This research investigated the application of riskscapes to landslides in the context of geospatial inquiry. Riskscapes are framed as a landscape of risk to represent risk spatially. Geospatial models for landslide riskscapes were developed to improve our understanding of the spatial context for landslides and their risks as part of the system of human-environment interactions. Spatial analysis using Geographic Information Systems (GIS) leveraged modeling methods and the distributed properties of riskscapes to identify and preserve these spatial relationships. This dissertation is comprised of four separate manuscripts. These projects defined riskscapes in the context of landslides, applied geospatial analyses to create a novel riskscape model to introduce spatial autocorrelation methods to the riskscape framework, compared geostatistical analysis methods in these landslide riskscape assessments, and described limitations of spatial science identified in the riskscape development process. The first project addressed the current literature for riskscapes and introduced landslides as a measurable feature for riskscapes. Riskscapes are founded in social constructivist theory and landslide studies are frequently based on quantitative risk assessment practices. The uniqueness of a riskscape is the inclusion of human geography and environmental factors, which are not consistently incorporated in geologic or natural hazard studies. I proposed the addition of spatial theory constructs and methods to create spatially measurable products. I developed a conceptual framework for a landslide riskscape by describing the current riskscape applications as compared to existing landslide and GIS risk model processes. A spatial modeling formula to create a weighted sum landslide riskscape was presented as a modification to a natural hazard risk equation to incorporate the spatial dimension of risk factors. The second project created a novel method for three geospatial riskscapes as an approach to model landslide susceptibility areas in Boulder and Larimer Counties, Colorado. This study synthesized physical and human geography to create multiple landslide riskscape models using GIS methods. These analysis methods used a process model interface in GIS. Binary, ranked, and human factor weighted sum riskscapes were created, using frequency ratio as the basis for developing a weighting scheme. Further, spatial autocorrelation was introduced as a recommended practice to quantify the spatial relationships in landslide riskscape development. Results demonstrated that riskscapes, particularly those for ranked and human factor riskscapes, were highly autocorrelated, non-random, and exhibited clustering. These findings indicated that a riskscape model can support improvements to response modeling, based on the identification of spatially significant clustering of hazardous areas. The third project extended landslide riskscapes to measurable geostatistical comparisons using geostatistical tools within a GIS platform. Logistic regression, weights of evidence, and probabilistic neural networks methods were used to analyze the weighted sum landslide riskscape models using ArcGIS and Spatial Data Modeler (ArcSDM). Results showed weights of evidence models performed better than both logistic regression and neural networks methods. Receiver Operator Characteristic (ROC) curves and Area Under the Curve validation tests were performed and found the weights of evidence model performed best in both posterior probability prediction and AUC validation. A fourth project was developed based on the limitations discovered during the analytical process evaluations from the riskscape model development and geostatistical analysis. This project reviewed the issues with data quality, the variations in results predicated on the input parameters within the analytical toolsets, and the issues surrounding open-source application tools. These limitations stress the importance of parameter selection in a geospatial analytical environment. These projects collectively determined methods for riskscape development related to landslide features. The models presented demonstrate the importance and influence of spatial distributions on landslide riskscapes. Based on the proposed conceptual framework of a spatial riskscape for landslides, weighted sum riskscapes can provide a basis for prioritization of resources for landslides. Ranked and human factor riskscapes indicate the need to provide planning and protection for areas at increased risk for landslides. These studies provide a context for riskscapes to further our understanding of the benefits and limitations of a quantitative riskscape approach. The development of a methodological framework for quantitative riskscape models provides an approach that can be applied to other hazards or study areas to identify areas of increased human-environment interaction. Riskscape models can then be evaluated to inform mitigation and land-use planning activities to reduce impacts of natural hazards in the anthropogenic environment