Dissertations / Theses on the topic 'Landside'

This thesis evaluates the impact of airports on land uses in and around airport land by a mixed research design, combining a statistical analysis based on secondary data and a case study on Brisbane Airport. The research finds that the role of airports as transport hubs is not the dominant mechanism that drives industries to locate in airport areas, rather, the surrounding city economy provided the primary impetus for business location. The findings provide a reference for policymakers regarding investment in airport expansion or construction, as well as a refining of the understanding of the local economic impact of airports.

The distribution of landslide type and age was analyzed to determine the causes and timing of landsliding, and to assess landslide hazards in the study area. 1173 landslides and zones of landsliding were mapped on 1:15,840 scale air photos and designated by their style of movement and age. Slides were assigned to one of four age classes based on their degree of m orphologic modification visible on air photos. Relative dating (RD) methods previously applied to glacial deposits were used to refine and calibrate the age classification. Eleven RD para meters were measured on 21 rockslide and 19 glacial deposits. Cluster analyses were run on the RD data set. Slides assigned to Age-Classes 4, 3+, and 2 tend to cluster with probable Pinedale, early Holocene, and Neoglacial-age moraines respectively. Cluster analyses indicate poor age resolution by the RD method from approximately early Altithermal to early Neoglacial time. Landslide age cannot be resolved in this study to a finer degree by the RD method than by the morphologic (air -photo) method. However, cluster analyses generally confirm age assignments and absolute age estimates of the four landslide age classes, despite limitations of the RD method such as boulder spalling, and variations in lithology, deposit type, and elevation/climate between sampled deposits. The temporal distribution of landslides indicates that mass movements may have occurred rather uniformly throughout Holocene time, with slightly higher rates of sliding during post-Altithermal time due to climatic effects associated with Neoglacial advances. Spatial analyses indicate that landslides cover 73% of the Cretaceous section. Development, such as logging and road construction, could trigger landsliding in the Cretaceous section. Landslides account for 15% and 10% of the outcrop areas of the Paleozoic and Triassic-Jurassic sections respectively. Debris flows and slump-earth flows dominate sliding in both sections, with minor numbers of rockslides present. Debris flows pose the greatest hazard in both sections. Fine-grained stratigraphic units have the highest landslide densities in both sections. The previous event locations define areas most susceptible to future sliding.

This thesis examines the use of network governance in US airport transportation planning activities involving taxicab services for airport patrons. The research provides US airports with new insights whereby they can successfully engage with both transportation regulatory agencies and taxicab service providers in developing mutually agreeable policies that foster the development of supply-side taxicab service improvements. A mix of quantitative and qualitative research methods is used to unearth how US airports interact with these actors, and to identify attitudes held by airport staff in their engagements involving airport taxicab planning matters. The research may ultimately lead to the achievement of sustainable increases in the air passenger ground transportation modal share at US airports, resulting in both desirable long-term operational and environmental benefits for airport management, those involved with the provision of airport taxicab services, and the traveling public.

Con il seguente documento si vuole esaminare l'utilita trasportistica dei sistemi di trasporto del tipo Automated People Mover passando da un inquadramento storico generale all'uso dei sistemi nell'ambito aeroportuale dall'inizio degli anni '60 fino ai tempi piu moderni. Dopo avere analizzato le configurazioni e le caratteristiche tipiche dei sistemi APM in ambito aeroportuale si definira quale tipologia di infrastruttura e stata privilegiata negli aeroporti europei e mondiali. Successivamente si prendera in esame lo stato dell'arte dei sistemi APM installati nell'aeroporto principale di Parigi e uno dei piu trafficati del mondo, l'Aeroporto Internazionale Charles de Gaulle; e del sistema installato nell'Aeroporto Internazionale Galileo Galilei di Pisa.

Gli aeroporti rappresentano complesse infrastrutture che svolgono un ruolo centrale nell’industria del traffico e che devono confrontarsi con aspetti e problematiche di svariata natura e complessità in quanto al loro interno convivono numerosi processi e servizi. Negli ultimi decenni la crescita della domanda nel settore del trasporto aereo ha implicato una crescente richiesta di servizi aeroportuali, che si trasmette nell'ulteriore necessità di sviluppare business rules con lo scopo di migliorare la qualità delle prestazioni offerte. Infatti, obiettivo primario di ogni aeroporto è assicurare alti livelli di servizio e performance che si traducono in un’esperienza di viaggio di elevata qualità per i passeggeri: a tale proposito modelli dinamici e software di simulazione si rivelano strumenti di grande utilità. Questa tesi verte sull'applicazione del software di simulazione CAST al terminal passeggeri dell'Aeroporto G. Marconi di Bologna. Grazie all'impiego del modulo CAST Terminal è stato possibile riprodurre uno scenario realistico e simulare due giornate rappresentative dal punto di vista del traffico, rispettivamente per il periodo "summer" ed il periodo "winter". L'analisi dei flussi di passeggeri e dei risultati in output ha permesso di fare luce sulle principali criticità all'interno dell'aerostazione, operando confronti grafici e quantitativi con gli standard fissati nella Carta dei Servizi 2016 e con gli indicatori di livello di servizio stabiliti dall'Airport Development Reference Manual (10° edizione). I principali colli di bottiglia rilevati riguardano gli elevati tempi di attesa per i controlli di sicurezza e per i controlli di immigrazione agli arrivi extra-Schengen e l’elevato affollamento delle sale di attesa davanti ad alcuni gate di imbarco in zona Schengen, dovuto all’accumulo di passeggeri in uno spazio di estensione ridotta.

This thesis has examined the 30km long rail corridor through the Lower Buller Gorge, on the Stillwater Ngakawau Line, between SNL96 and 126km, using a landslide risk management approach. The project area is characterised by high annual rainfall (>2,000mm per year), and steep topography (slopes typically ≥20°) adjacent to the rail corridor. The track formation generally follows the natural contour near the base of the hillslope through the Lower Buller Gorge, and consequently involves many curves but relatively limited cut slopes into adjacent rock outcrops. The distance between the base of adjacent hillslopes and rail is frequently <2m horizontally. A variety of basement and Tertiary lithologies are present, including granite, breccias, indurated sandstone/mudstone, and limestone. The primary focus of this thesis has been on upslope-sourced landsliding onto the rail corridor, and on two short lengths (20m and 450m) that currently have a 25km/hour speed restriction imposed at Whitecliffs and Te Kuha respectively. Rainfall-induced and earthquake-generated landslide triggering mechanisms were examined in detail. A landslide inventory has been compiled to determine the characteristics and distribution of identified slope failures over time, and to establish any correlation with topography and geology. Sixty individual landslide events were identified since the line became fully operational in the 1940s, based on desktop reviews, and field inspections for more recent events. To reflect the presence of small magnitude landslide events, a project-specific logarithmic classification of landslides was adopted from <10m³ (very small volume) to ≥10,000m³ (very large volume). An absence of a higher proportion of ‘very small’ to ‘small’ landslide volumes (<100m³) in the inventory reflects incomplete reporting of these comparatively lower magnitude, but higher frequency, events. The establishment of a robust landslide inventory to document future events, in a consistent and readily accessible format, is required for continued monitoring and review of landslide risk management practices in the Lower Buller Gorge. Combining landslide inventory data and physical characteristics of the project area enabled the development of a qualitative landslide zonation map that assigned ‘high’, ‘high-moderate’, ‘moderate’ and ‘low’ landslide susceptibility classes. The principal area of slope instability above the rail corridor is 22.5km in length between SNL103.5 and 126.0km, associated predominantly with basement lithologies (Tuhua Granite; Hawks Crag Breccia; Greenland Group). The most frequently occurring landslides are shallow, typically less than 3m deep, translational failures triggered in regolith or colluvium materials. Rainfall-induced debris slides and flows are dominant, given the high annual rainfall and associated high frequency of high intensity or long duration rainfall events. Very small to medium landslides (<1,000m³) have the potential to impact the rail corridor with an average frequency of around one every two years, causing damage to infrastructure or affecting rail operations. Very large landslides (≥10,000m³) can be expected every 10 to 20 years based on a limited historical record. The narrow rail corridor and absence of sufficient catch areas above or adjacent to the rail causes continual operational challenges due to upslope-sourced landslide debris, and high susceptibility to slope failures, particularly west of SNL103.50km. Development of a rainfall-threshold for proactive inspection of the rail corridor is recommended, including the establishment of a rain gauge network through the Lower Buller Gorge. Earthquake-generated landslides significantly impacted the rail during the magnitude 7.1 Inangahua earthquake in 1968 and to a much lesser extent during the magnitude 6.1 Westport earthquake in 1991. The rail was not fully constructed through the Lower Buller Gorge at the time of the magnitude 7.8 Buller (Murchison) Earthquake in 1929, which generated widespread landsliding in the Buller and Nelson regions. Earthquake-generated landsliding can be expected through the Lower Buller Gorge from earthquakes of magnitude ≥6, and track inspection is recommended in the event of magnitude 5 or greater earthquakes. Detailed geological characterisation and mapping at Whitecliffs and Te Kuha was conducted, including a LiDAR survey at Whitecliffs that enabled visualisation of the ground surface without the interference of vegetation. The limestone outcrop at Whitecliffs comprises 60-70m high near-vertical cliffs with a well-established talus apron at the base, extending to the rail corridor. Three widely spaced open fractures sets are present at the top of Whitecliffs that propagate into the cliff-face. There has been no detectable movement on selected key fracture sets since monitoring commenced in 1993 and there is no confirmed evidence of large-scale cliff collapse during the 1968 Inangahua earthquake. Whitecliffs is not as susceptible to failure as other slopes inspected in the project area due to structural controls, primarily being the dipping of strata back into the cliff-face and widely space joint sets. Establishment of inspection protocols for earthquake events impacting the area, including real-time monitoring of selected fractures at Whitecliffs is recommended. A 2km-length corridor site model produced for Te Kuha demonstrated ‘high’ landslide susceptibility is not confined to slopes above the existing 450m speed restriction zone. Removal of the speed restrictions at Whitecliffs and Te Kuha can be considered, as the increased exposure time is not considered sufficient justification given the extent of other susceptible areas to landsliding affecting the Lower Buller Gorge rail corridor. The principal conclusion from this thesis project is that there is on-going risk to rail operations predominantly from shallow translational landsliding in regolith-colluvium materials. The majority of these will be generated by long-duration or intense rainfall events. Development of threshold-based methods for effective track management is recommended, including the establishment of a rain gauge network through the Lower Buller Gorge, and landslide inventory database. Site-specific engineering measures could be adopted, such as catch benches or avalanche-type shelters, where justified on a cost-benefit basis.

This thesis examines the indirect impact of natural hazards on infrastructure networks. It addresses several key themes and issues for hazard assessment, network modelling and risk assessment using the case study of landslides impacting the national road network in Scotland, United Kingdom. The research follows four distinct stages. First, a landslide susceptibility model is developed using a database of landslide occurrences, spatial data sets and logistic regression. The model outputs indicate the terrain characteristics that are associated with increased landslide potential, including critical slope angles and south westerly aspects associated with increased rates of solar irradiance and precipitation. The results identify the hillslopes and road segments that are most prone to disruption by landslides and these indicate that 40 % (1,700 / 4,300 km) of Scotland s motorways and arterial roads (i.e. strategic road network) are susceptible to landslides and this is above previous assessments. Second, a novel user-equilibrium traffic model is developed using UK Census origin-destination tables. The traffic model calculates the additional travel time and cost (i.e. indirect impacts) caused by network disruptions due to landslide events. The model is applied to calculate the impact of historic scenarios and for sets of plausible landslide events generated using the landslide susceptibility model. Impact assessments for historic scenarios are 29 to 83 % greater than previous, including £1.2 million of indirect impacts over 15 days of disruption at the A83 Rest and Be Thankful landslide October 2007. The model results indicate that the average impact of landslides is £64 k per day of disruption, and up to £130 k per day on the most critical road segments in Scotland. In addition to identifying critical road segments with both high impact and high susceptibility to landslides, the study indicates that the impact of landslides is concentrated away from urban centres to the central and north-west regions of Scotland that are heavily reliant on road and haulage-based industries such as seasonal tourism, agriculture and craft distilling. The third research element is the development of landslide initiation thresholds using weather radar data. The thresholds classify the rainfall conditions that are most commonly associated with landslide occurrence in Scotland, improving knowledge of the physical initiation processes and their likelihood. The thresholds are developed using a novel optimal-point threshold selection technique, high resolution radar and new rain variables that provide spatio-temporally normalised thresholds. The thresholds highlight the role of the 12-day antecedent hydrological condition of soils as a precursory factor in controlling the rain conditions that trigger landslides. The new results also support the observation that landslides occur more frequently in the UK during the early autumn and winter seasons when sequences or clustering of multiple cyclonic-storm systems is common in periods lasting 5 to 15 days. Fourth, the three previous elements are combined to evaluate the landslide hazard of the strategic road segments and a prototype risk assessment model is produced - a catastrophe model. The catastrophe model calculates the annual average loss and aggregated exceedance probability of losses due to the indirect impact of landslides in Scotland. Beyond application to cost-benefit analyses for landslide mitigation efforts, the catastrophe model framework is applicable to the study of other natural hazards (e.g. flooding), combinations of hazards, and other infrastructure networks.

Many settlements in the Guatemala City Metropolitan Area (GCMA) face significant possibilities of fatalities due to their location in steep ravines that are subjected to periodic large-scale landslides. Since the housing in the at-risk areas is relatively low-cost, it is typically cost-prohibitive to mitigate the risk to an acceptable level. Thus, permanent relocation is the only truly viable option to ensure the long-term safety of everyone. However, there are several economic and social obstacles impeding successful implementation of a relocation program. Still, there are many other landslide risk reduction techniques (such as retaining walls, community drainage systems, and alert systems) implemented by government organizations and non-profit groups. These techniques are helpful in landslide risk reduction (LRR), but residents are only partially involved in the entire process. Therefore, increasing residents’ education and ability to better understand their level of landslide risk will help with LRR. Residents can integrate and collaborate with the government organizations and non-profits implementing mitigation techniques and of even greater benefits, the education and ability for residents to understand their landslide risk can provide additional avenues for LRR not otherwise achievable. The purpose of this research is to develop a landslide-risk-rating-system (LRRS) that can be used by trained residents to better understand their risk (similar to other landslide or rockfall hazard-rating systems commonly used by department of transportation organizations). The focus of this LRRS is only on small-scale landslides (typically the size of a house or less) because evaluating the risk of large-scale landslides is too complicated to be done by trained non-technical experts. The LRRS asks questions related to landslide risk that can be used to calculate a landslide risk score to indicate the relative level of risk. The LRRS was created by reviewing published literature documenting other landslide rating systems and incorporating similar factors correlated with landslide risk. Then, forty sites were visited in the GCMA to inventory the factors at houses that are vulnerable to landslides in order to evaluate which factors were most useful for predicting the relative risk. The predicted risk scores were compared to ranked risk scores estimated by the author to ensure the results were valid. Statistical analysis identified which of these factors best-predicted landslide risk. These factors include slope angle, slope height, strength of slope material or material type, aperture of cracks, spatial impact, largest probable landslide volume, largest probable percentage of the living area that could be impacted from a landslide, and total person-hours a living area is occupied per day. Future work should focus on the transformation of the tool into a more user-friendly format for use by residents, the implementation process, and monitoring plan.

The economic rationale for public intervention in decisions regarding landslide hazard mitigation was examined through a cost-benefit analysis. A study area in Cincinnati, Ohio was used to test whether a public agency decision rule is suboptimal to a private decision rule in maximizing net benefits from landslide mitigation. A 1985 U.S. Geological Survey (U.S.G.S.) report on landslide mitigation in Cincinnati, Ohio formed the basis for the cost-benefit analysis. Expected gross benefits from mitigation were determined by multiplying the probability of a landslide by an estimate of the property damages. A landslide probability model developed by the U.S.G.S. was tested against data for a study area in Pittsburgh, Pennsylvania. A Spearman rank correlation test, comparing actual and predicted landslide occurrence, indicated that the model is a good predictor and could be used to predict landslides in other areas of similar geology. Due to the poor quality of data on actual landslide damages, a regression equation was estimated to predict the actual damages resulting from a landslide in the Cincinnati study area. A cost-benefit analysis was performed for the Cincinnati study area using three different approaches to measuring property damages. The results of the analysis support the hypothesis. In the most extreme case, annualized net benefits from mitigation are equal to $2.1 million under the private decision rule compared with only $1.6 million under the public agency decision rule.
Master of Arts

Landslides display a wide variety of behaviors ranging from slow persistent motion to rapid acceleration and catastrophic failure. Given the variety of possible behaviors, improvements to our understanding of landslide mechanics are critical for accurate predictions of landslide dynamics. Recent advances in remote sensing techniques, like satellite radar interferometry (InSAR), now enable high-resolution spatial and temporal measurements that provide insight into the mechanisms that control landslide behavior. In this dissertation, I use InSAR and high-resolution topographic data to identify 50 slow-moving landslides in the Northern California Coast Ranges and monitor their kinematics over 4 years. These landslides have similar mechanical properties and are subject to the same external forcings, which allows me to explore geometrical controls on kinematics. Each landslide displays distinct kinematic zones with different mean velocities that remain spatially fixed. Because these deformation patterns are sensitive to subsurface geometry, I employ a mathematical model to infer landslide thickness and find that these landslides exhibit a highly variable thickness and an irregular basal sliding surface. Time series analysis reveals that each landslide displays well-defined seasonal velocity changes with a periodicity of ∼ 1 year. These velocity variations are driven by precipitation- induced changes in pore-water pressure that lag the onset of rainfall by up to 40 days. Despite significant variations in geometry, I find no systematic differences in seasonal landslide behavior. To further explore how stress perturbations control landslide motion, I develop a mechanical model that reproduces both the displacement patterns observed at slow-moving landslides and the acceleration towards failure exhibited by catastrophic events. I find that catastrophic failure can only occur when the slip surface is characterized by rate-weakening friction and its spatial dimensions exceed a critical nucleation length that is shorter for higher effective stresses. These model simulations support my conclusions from the remote sensing analysis but also provide insight into the long-term evolution of landslides. This dissertation includes both previously published and unpublished co- authored material.

Skred är en av de naturliga processer som formar landskapet omkring oss. De kan dock, om de sker ibebyggda områden, orsaka stor skada på byggnader, infrastruktur och utgöra en fara för människors liv.Det är därför viktigt att kunna identifiera områden där skred potentiellt kan ske så att lämpliga åtgärderkan vidtas i tid. En modell har tagits fram av Statens geotekniska institut (SGI) och Sveriges geologiskaundersökning (SGU) för att ge en första indikation på var skred kan ske. Modellen baseras på en algoritmav Tryggvason et al. (2015) där områden som består av finkorniga jordarter och där lutningsförhållandetär minst 1:10 betraktas som skredkänsliga. Syftet med denna studie var att undersöka till vilken gradmodellens aktsamhetsområden sammanfaller med tidigare skred från SGI och SGUs databaser. 90 - 94% av de tidigare skreden överlappade med modellerade aktsamhetsområden. Möjliga anledningar till attskred hamnat utanför dessa områden undersöktes även. Att de befinner sig i en jordart som inte betraktassom skredkänslig och att lutningen numera är lägre än tröskelvärdet för modellen var de huvudsakligaanledningarna till detta.
A landslide is a type of mass movement down a slope. It is a natural part of the evolution of the landscapearound us but can cause extensive damages on buildings, infrastructure and pose a threat to human livesif they occur in populated areas. It is therefore important to know which areas that are prone to landslidesso that appropriate measures can be taken in time. It is possible to calculate how stable a certain soil isby taking samples of it and testing it in the lab. In these tests it is determined how sensitive the soil is tovibrations, a higher water content and/or if it is remolded. However, this takes time and require a lot ofwork. Since not all soil types are equally sensitive these tests do not have to be performed on everyslope, but it is important that the most sensitive areas are not overlooked. For this reason, a model hasbeen developed that displays areas where the slope stability might need to be examined prior, forexample, larger infrastructure projects are started. From previous studies it has been found thatlandslides mostly occur in fine grained soils, like silt and clay, and where the slope is steeper than 5.7degrees. Areas that consist of any of these soil types and has a slope over this threshold are consideredpotentially sensitive to landslides in the model. The purpose of this study was to assess how well themodel is at identifying areas that might be prone to landslides. This was done by determining how manyof previous landslides, that are registered in two databases, that fall within the areas marked aspotentially sensitive. Why some landslides were located outside of these areas was also examined. Themain reasons were that the soil type the landslide occurred in is not considered sensitive by the modelor the inclination of the slope have changed since the landslide occurred. 90 - 94 % of the previouslandslides were found to be located within areas that the model point out as potentially sensitive.

Landslides are one of the most destructive disasters that cause damage to both property and life every year. Various methodologies have been reported for landslide susceptibility mapping. Statistical methods are widely used to fit the mathematical relationship between observed landslides and the factors considered to influence the slope failure, and have shown remarkable accuracy. Among these models, frequency ratio and logistic regression models are the most popular for its simplicity and high accuracy. However, virtually all previous studies randomly extracted and reserved a portion of historical landslide records to perform the model evaluation. The purpose of this study are: 1) To produce a landslide susceptibility map for Lantau Island by GIS and remote sensing methods as well as statistical modeling techniques 2) To add extra value to the literature of evaluating their “prediction rate” (rather than “success rate”) for landslide susceptibility mapping in a temporal context. The mountainous terrain, heavy and prolonged rainfall, as well as dense development near steep hillsides make Hong Kong as one of the most vulnerable metropolitans to the risk of landslides. As there is an increasingly high demand for land resource to support the growth of economic and population, regional specific landslide susceptibility assessment in Hong Kong is necessary for hazard management and effective land use planning. Firstly, the spatial relationship among landslide occurrence and nine causative factors (elevation, slope aspect, slope gradient, plan curvature, profile curvature, NDVI, distance to river, SPI and lithology) were explored. The distribution of landslides on Lantau Island is largely governed by a combination of geo-environmental conditions, such as elevation of 200m-300m, slope gradient of 25°-35°, slope aspect of west or northwest, high degree of positive or negative plan curvature and profile curvature, sparse vegetation in terms of NDVI in 0.3-0.5 (shrub/grassland), proximity (0.6-1.2km) to fault line, presence of volcanic bedrocks (especially rhyolite lava and tuff) and high stream power index. Second, landslide susceptibility maps were generated by frequency ratio and logistic regression model, respectively. Validations of the mapping results were performed by calculating relative operating characteristics (ROC). The models, trained by 1,864 (70%) landslides records in the Enhanced Natural Terrain Landslide Inventory (ENTLI) from 2000 to 2008, were validated by subsequent 799 (30%) landslide occurred from 2008 to 2009. The validation result shows that logistic regression model (88.70%) possesses a better prediction power than frequency ratio model (78.00%) for the study area. The findings suggested that logistic regression analysis is more reliable for landslide susceptibility mapping. The resultant maps are expected to provide a scientific assessment of the risk areas with respect to landslides on Lantau Island, and to serve as a basis for decisions or justification of the Lantau development planning. Keywords: landslide susceptibility; frequency ratio; logistic regression; temporal verification; GIS; Hong Kong

An integration of geological and geophysical techniques has been used to characterize the internal structure of the Little Valley Landslide in Draper, Utah, USA. The Little Valley Landslide is a pre-historic landslide as old as 13ka B.P. It is found to consist of chaotic and disturbed weathered volcanic units derived from Tertiary age volcanics that comprise a great portion of the Wasatch Range. Geotechnical investigations that were integrated with the geophysical results included excavation of trenches and drilling of boreholes. Geophysical methods, in particular high-resolution seismic data, were used to provide a framework for interpreting the geotechnical observations. High-resolution seismic reflection data, seldom used in landslide investigations, were acquired and processed in order to image the basal or glide surface of the landslide and the structure underlying the landslide. The integration of the geotechnical and geophysical investigations provided a better understanding of the geometry of a portion of the Little Valley Landslide. Trenching and drilling identified landslide material in the subsurface. The high-resolution seismic reflection data imaged the glide surface with the onset of coherent reflectivity. A decollement or glide surface underlies the landslide indicating a large mass movement. The glide surface is observed on the seismic reflection profiles to be deepest in the center portion of the landslide. It is observed in the seismic reflection images to shallow up slope and creating a trough-like shape feature. A contour map modeling the middle of the Little Valley Landslide is derived from the seismic data. This study shows that seismic reflection techniques can be successfully used in complex alpine landslide regions. They are also efficient and cost-effective tools when compared to trenching and drilling investigations. The seismic data can (1) provide a framework to link geological data and (2) take the place of an extensive trenching and drilling program.

Earthquake triggered landslides cause loss of life, destroy structures, roads, powerlines, and pipelines and therefore they have a direct impact on the social and economic life of the hazard region. The damage and fatalities directly related to strong ground shaking and fault rupture are sometimes exceeded by the damage and fatalities caused by earthquake triggered landslides. Even though future earthquakes can hardly be predicted, the identification of areas that are highly susceptible to landslide hazards is possible. For geographical information systems (GIS) based deterministic slope stability and earthquake-induced landslide analysis, the grid-cell approach has been commonly used in conjunction with the relatively simple infinite slope model. The infinite slope model together with Newmark's displacement analysis has been widely used to create seismic landslide susceptibility maps. The infinite slope model gives reliable results in the case of surficial landslides with depth-length ratios smaller than 0.1. On the other hand, the infinite slope model cannot satisfactorily analyze deep-seated coherent landslides. In reality, coherent landslides are common and these types of landslides are a major cause of property damage and fatalities. In the case of coherent landslides, two- or three-dimensional models are required to accurately analyze both static and dynamic performance of slopes. These models are rarely used in GIS-based landslide hazard zonation because they are numerically expensive compared to one dimensional infinite slope models. Building metamodels based on data obtained from computer experiments and using computationally inexpensive predictions based on these metamodels has been widely used in several engineering applications. With these soft computing methods, design variables are carefully chosen using a design of experiments (DOE) methodology to cover a predetermined range of values and computer experiments are performed at these chosen points. The design variables and the responses from the computer simulations are then combined to construct functional relationships (metamodels) between the inputs and the outputs. In this study, Support Vector Machines (SVM) and Artificial Neural Networks (ANN) are used to predict the static and seismic responses of slopes. In order to integrate the soft computing methods with GIS for coherent landslide hazard analysis, an automatic slope profile delineation method from Digital Elevation Models is developed. The integrated framework is evaluated using a case study of the 1989 Loma Prieta, CA earthquake (Mw = 6.9). A seismic landslide hazard analysis is also performed for the same region for a future scenario earthquake (Mw = 7.03) on the San Andreas Fault.

LiDAR (Light Detection and Ranging) elevation data were collected in the Panther Creek Watershed, Yamhill County, Oregon in September and December, 2007, March, 2009 and March, 2010. LiDAR derived images from the March, 2009 dataset were used to map pre-historic, historic, and active landslides. Each mapped landslide was characterized as to type of movement, head scarp height, slope, failure depth, relative age, and direction. A total of 153 landslides were mapped and 81% were field checked in the study area. The majority of the landslide deposits (127 landslides) appear to have had movement in the past 150 years. Failures occur on slopes with a mean estimated pre-failure slope of 27° ± 8°. Depth to failure surfaces for shallow-seated landslides ranged from 0.75 m to 4.3 m, with an average of 2.9 m ± 0.8 m, and depth to failure surfaces for deep-seated landslides ranged from 5 m to 75m, with an average of 18 m ± 14 m. Earth flows are the most common slope process with 110 failures, comprising nearly three quarters (71%) of all mapped deposits. Elevation changes from two of the successive LiDAR data sets (December, 2007 and March, 2009) were examined to locate active landslides that occurred between the collections of the LiDAR imagery. The LiDAR-derived DEMs were subtracted from each other resulting in a differential dataset to examine changes in ground elevation. Areas with significant elevation changes were identified as potentially active landslides. Twenty-six landslides are considered active based upon differential LiDAR and field observations. Different models are used to estimate landslide susceptibility based upon landslide failure depth. Shallow-seated landslides are defined in this study as having a failure depth equal to less than 4.6 m (15 ft). Results of the shallow-seated susceptibility map show that the high susceptibility zone covers 35% and the moderate susceptibility zone covers 49% of the study area. Due to the high number of deep-seated landslides (58 landslides), a deep-seated susceptibility map was also created. Results of the deep-seated susceptibility map show that the high susceptibility zone covers 38% of the study area and the moderate susceptibility zone covers 43%. The results of this study include a detailed landslide inventory including pre-historic, historic, and active landslides and a set of susceptibility maps identifying areas of potential future landslides.

Developing detailed landslide inventory maps of prehistoric landslides is essential to interpret the frequency and conditions under which slopes have failed. When coupled with age estimates, landslide inventories can yield better predictions for future slope failures, thereby improving hazard assessments and increasing chances for mitigation. Developing proxies for landslide age is an important area of research, but age dating prehistoric landslides can be challenging due to sparse datable organic material within landslide deposits, and to time or access constraints. In this thesis, surface roughness of the landslide deposit is used to construct a best-fit age-roughness model that quantitatively assigns age based on smoothing of the deposit with time for landslides in the Green River Valley (GRV), located in King County, Washington. Hillslopes in the valley are composed of glacial sediments and are prone to failure caused by three main triggers: over steepening caused by lateral migration of the Green River, Holocene climatic change (precipitation and temperature), and seismicity (Cascadia Subduction Zone and the Seattle Fault). We examine the distribution of landslides in the GRV using high-resolution lidar data and find a threshold relief of approximately 60 m corresponds to landslide locations. Four dated samples with ages ranging from 492 to 0 cal. BP defined age-roughness models that showed 44 to 51 of the 61 mapped landslides occurred from 5000 to 100 cal. BP, after the climate changed to cooler and wetter conditions. These 61 landslides, on average, decrease in age as you move upstream, consistent with upstream migration of a knickzone. From these age-roughness models the GRV has a recurrence interval of one landslide every 38 years since 1000 cal. BP (26 landslides/1000 years), which has implications for managing landslide hazards.

Målet med denna studie är att framställa en modell för sannolikheten för skred i Cuenca del Arga i Navarra, Spanien, med hjälp av GIS och oskarp logik. Utifrån denna modell framställs en karta som visar områden där det finns sannolikhet för skred. Övergripande har metoden skett i fyra steg. Först har en skredindexkarta framställts, sedan har medlemsfunktioner skapats utifrån dessa med hjälp av skredriskparametrar. De ingående parametrarna har varit sluttningsvinkel, topografisk fuktighetsindex, avstånd till vattendrag, jordmån och markanvändning. Sedan har medlemsfunktionerna applicerats på parametrarna, som sedan slutligen kombinerats genom WLC (weighted linear combination). Detta resulterade i en sannolikhetskarta för skred med fem klasser.
The aim of this study is to construct a model in GIS (geographical information system) for landslide susceptibility mapping for Cuenca del Arga in Navarre, Spain, to identify potential areas for landslides. The model is based on fuzzy logic approach and the parameters are overlaid with WLC (weighted linear combination).

Landslides represent a serious hazard to people and property in the Pacific Northwest. Currently, the factors leading to sudden catastrophic failure vs. gradual slow creeping are not well understood. Utilizing high-resolution monitoring techniques at a sub-annual temporal scale can help researchers better understand the mechanics of mass wasting processes and possibly lead to better mitigation of their danger. This research used historical imagery analysis, precipitation data, aerial lidar analysis, Structure from Motion (SfM) photogrammetry, terrestrial laser scanning (TLS), and hydrologic measurements to monitor displacement of the Silt Creek Landslide in the western Cascade Mountain Range in Linn County, Oregon. This landslide complex is ~4 km long by ~400 m wide. The lower portion of the landslide reactivated following failure of an internal scarp in June 2014. Precipitation was measured on site and historical precipitation data was determined from a nearby SNOTEL site. Analysis of aerial lidar data found that the internal scarp failure deposited around 1.00 x 10⁶ m³ of material over an area of 1.20 x 10⁵ m² at the uppermost portion of the reactivated slide. Aerial lidar analysis also found that displacement rates on the slide surface were as high as 3 m/yr during the 2015 water year, which was the year immediately following the failure. At the beginning of the 2016 water year, very low altitude aerial images were collected and used to produce point cloud data, via SfM, of a deformed gravel road which spans a portion of the reactivated slide. The SfM data were complimentary to the aerial and TLS scans. The SfM point cloud had an average point density of > 7500 points per square meter. The resulting cloud was manipulated in 3D software to produce a model of the road prior to deformation. This was then compared to the original deformed model. Average displacement found in the deformed gravel road was 7.5 m over the 17 months between the scarp failure and the collection of the images, or ~3 m/yr. TLS point clouds were collected quarterly over the course of the 2016 water year at six locations along the eastern margin of the reactivated portion of the landslide. These 3D point cloud models of the landslide surface had an average density of 175 points per square meter. Scans were georeferenced to UTM coordinates and relative alignment of the scans was accomplished by first using the iterative closest point algorithm to align stable, off-slide terrain, and then applying the same rigid body translation to the entire scan. This was repeated for each scan at each location. Landmarks, such as tree trunks, were then manually selected at each location and their coordinates were recorded from the initial scan and each successive scan to measure displacement vectors. Average annual displacement for the 2016 water year ranged from a maximum of 0.92 m/yr in the uppermost studied area of the slide, to a low of 0.1 m/yr at the toe. Average standard deviation of the vectors of features on stable areas was 0.039 m, corresponding to a minimum detectable displacement of about ±4 cm. Displacement totals decreased with increasing distance downslope from the internal scarp failure. Additionally, displacement tended to increase with increasing distance laterally onto the slide body away from the right margin at all locations except the uppermost, where displacement rates were relatively uniform for all landmarks. Volumetric discharge measurements were collected for Silt Creek in 2016 using salt dilution gauging and found that discharge in the upslope portion of the study area wwas ~1 m3/s and increased to ~1.6 m3/s in the downslope portion. Landslide displacement rates were found to be much lower during the 2016 water year than during the 2015 water year, despite higher precipitation. This suggests that the over-all displacement trend was decoupled from precipitation values. Displacement rates at all locations on the slide decreased with each successive scan period with some portions of the landslide stopping by autumn of 2016, suggesting the study captured the slide as it returned to a state of stability. The spatial and temporal pattern of displacement is consistent with the interpretation that the landslide reactivation was a response to the undrained load applied by the internal scarp failure. This finding highlights the importance of detailed landslide monitoring to improve hazard estimation and quantification of landslide mechanics. (Abstract shortened by ProQuest.)

Landslide hazard assessment of densely forested, remote, and difficult to access areas can be rapidly accomplished with airborne light detection and ranging (lidar) data. An evaluation of geomorphic change by lidar-derived digital elevation models (DEMs) coupled with geotechnical soils analysis, aerial photographs, ground measurements, precipitation data, and numerical modeling can provide valuable insight to the reactivation process of unstable landslides. A landslide was selected based on previous work by Mickleson (2011) and Burns et al. (2010) that identified the Madrone Landslide with significant volumetric changes. This study expands on previous work though an evaluation of the timing and causation of slope failure of the Madrone Landslide. The purpose of this study was to evaluate landslide morphology, precipitation data, historical aerial photographs, ground crack measurements, geotechnical properties of soil, numerical modeling, and elevation data (with multi-temporal lidar data), to determine the conditions associated with failure of the Madrone Landslide. To evaluate the processes involved and timing of slope failure events, a deep seated potentially unstable landslide, situated near the contact of Eocene sedimentary and volcanic rocks, was selected for a detailed analysis. The Madrone Landslide (45.298383/-123.338796) is located in Yamhill County, about 12 kilometers west of Carlton, Oregon. Site elevation ranges from 206 meters (m) North American Vertical Datum (NAVD-88) near the head scarp to 152 m at the toe. The landslide is composed of two parts, an upper more recent rotational slump landslide and a lower much older earth flow landslide. The upper slide has an area of 2,700 m2 with a head scarp of 5-7 m and a volume of 15,700 m3. The lower earth flow has an area of 2300 m2, a head scarp of 15 m, and a volume of 287,500 m3. Analysis of aerial photographs indicates the lower slide probably originated between 1956 and 1963. The landslide is located at a geologic unit contact of Eocene deep marine sedimentary rock and intrusive volcanic rock. The landslide was instrumented with 20 crack monitors established across ground cracks and measured periodically. Field measurements did not detect ground crack displacement over a 15 month period. Soil samples indicate the soil is an MH soil with a unit weight of 12 kN/m3 and residual friction angle of 28φ'r which were both used as input for slope stability modeling. Differential DEMs from lidar data were calculated to generate a DEM of Difference (DoD) raster to identify and quantify elevation changes. Historical aerial photograph review, differential lidar analysis, and precipitation data suggest the upper portion of the landslide failed as a result of the December 2007 storm.

Landslides, in their various forms, are a common hazard in mountainous terrain, especially in seismically active areas and regions of high rainfall. The West Coast region of New Zealand is dissected by many active faults, experiences frequent earthquakes and in many locations annual rainfall exceeds ten meters. Consequently, landslides are widespread in the region and since European settlement began, have been responsible for 27 deaths, along with frequent damages to road and rail infrastructure, settlements and agricultural land. This study identifies areas that are susceptible to rainfall triggered landslides in the West Coast region. To achieve this, a landslide susceptibility map was produced using bivariate statistics and the analytical hierarchy process. It has an accuracy that predicts 80% of all the landslides in the top 40% of the susceptibility scores on the map. As part of this process, 3221 rainfall triggered landslides and 522 earthquake (or other trigger) triggered landslides have been mapped and digitised into a Geographic Information System. In parallel with this, a descriptive historical catalogue of 1987 landslides has been compiled from the available sources. These new tools provide decision-makers with an enhanced means of managing landslide hazards in the West Coast region. In order to avoid misinterpretation the study has been carried out in compliance with the “Guidelines for landslide susceptibility, hazard and risk zoning for land use planning”, which was published in 2008 by the Joint Technical Committee on Landslides and Engineered Slopes. The tools developed in this thesis represent a fundamental step in land-use planning and set-up of landslide hazard management in the West Coast region.

Located in the Columbia River Gorge, The Red Bluff Landslide (18.8 km2) is one of four large landslides that make up the Cascade Landslide Complex. In its current form, the Red Bluff Landslide is a post-Missoula Flood feature made up of two components: an active upper lobe (8.6 km2) that is translational, creeping to the south at 25 cm/yr and spreading laterally to the east at 6 cm/yr over a semi-fixed portion (10.2 km2) of the Red Bluff Landslide area that has been "smoothed" by Missoula Floods. The upper active lobe is the landslide debris accumulated since Missoula Flood time (~15,000 yr. BP). Five separate collapse events have been identified and rock failures along the main scarp headwalls continue. Two rock avalanches on the Red Bluff Landslide were mapped. The Old Greenleaf Basin Rock Avalanche is estimated to have occurred 100 to 150 years ago, represents the fifth collapse event on the Red Bluff Landslide, and covers an area of 200,000 m2. It has a volume of 4.2 million m3; its length is 748 m and has a width of 215 m. On January 3, 2008, the Greenleaf Basin Rock Avalanche occurred, flowing over the Old Greenleaf Basin Rock Avalanche, covering an area of 100,000 m2 and deposited a volume of about 375,000 m3. Its length is 730 m with an average depth of 1.22 m. It contributed approximately 0.058% of the total volume and 0.01% of the surface area to the active upper lobe portion of the Red Bluff Landslide. The Greenleaf Basin Rock Avalanche was determined to be insignificant in the movement of the active part of the Red Bluff Landslide during the winter of 2007-2008. The original Cascade Landslide Complex map (Wise, 1961) included the Mosley Lakes Landslide which has now been removed because it lacked the characteristics of a landslide like a scarp. The original complex (35.5 km2) has been renamed the "Greater Cascade Landslide Complex" (43.0 km2), with the addition of the adjacent Stevenson Slide and the elimination of the Mosley Lakes Landslide.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2005.
Includes bibliographical references (v. 2, p. 736-750).
Landslides are natural phenomena which are difficult to predict because their initiation depends on many factors and on the interaction between these factors. The annual number of causalities caused by landslides is in the thousands, and infrastructural damage is in the billions of dollars. To satisfy the increasingly urgent societal demand for protection against landslides, it is necessary to systematically assess and manage landslide hazard and risk. This can be done using principles of decision making under uncertainty. We develop an advanced combined hydrologic - stability model that is better capable of assessing landslide hazards than current models used in landslide analyses. This model allows one to evaluate landslide hazards deterministically. We use the model to study landslide failure mechanisms, and classify these according to the manner in which a slope gets saturated during rain. We showed that slopes with great depths to bedrock and shallow depths to the water table, tend to fail by saturation from below, resulting in deep seated landslides, and slopes with deep lying water tables tend to fail by saturation from above, resulting in shallow landslides.
(cont) Landslide hazards include, by definition, uncertainties which can be expressed probabilistically. Uncertainties arise from parameters and from models. We develop efficient techniques to formally incorporate parameter uncertainties into the combined hydrologic - stability model, and hence into the hazard assessment procedure. We then show that landslide hazards are significantly influenced by the joint probability distribution of the soil strength parameters and the strength submodel(s) used in the stability models, and by the soil characteristic curve submodel(s) used in the hydrologic models. This study leads to a better understanding of landslide mechanisms and to advanced models that assess landslide hazards more accurately than current models. The results of parameter uncertainty investigations show which parameters are most important in landslide analyses, and hence where it is worthwhile to obtain more information. The results of model uncertainty investigations show which models are most important in landslide analyses, and hence where further research needs to be undertaken.
by Karim S. Karam.
Ph.D.

Tsunamis generated by landslides and volcanic island collapses account for some of the most catastrophic events, and the largest recorded wave runup was generated by a supercritical landslide impact in Lituya Bay, Alaska. Unfortunately field data from these types of events is very limited, consisting of rare field measurements of landslide scarp, landslide deposit and tsunami runup, as well as eyewitness accounts. Critically important field data related to the landslide motion and tsunami evolution are lacking. Source and runup scenarios based on real world events are physically modeled in the three- dimensional NEES tsunami wave basin at Oregon State University. A unique pneumatic landslide tsunami generator (LTG) was deployed to simulate landslides with varying geometry and kinematics. The LTG consists of a sliding box filled with up to 1,350 kg of naturally rounded river gravel or cobbles which is accelerated by means of four pneumatic pistons down the 2H: 1V slope, launching the granular landslide towards the water at velocities of up to 6 m/s. Topographical and bathymetric features can greatly affect wave characteristics and runup heights. Landslide generated tsunamis were studied in different topographic and bathymetric configurations: basin-wide propagation and runup, a narrow fjord and curved headland configurations, and a conical island setting simulating landslides off an island or a volcanic flank collapse. Water surface elevations were measured using an array of resistance wave gauges. The granular landslide width, thickness and front velocity were measured using above and underwater cameras. Wave runup was measured with a combination of resistance wave gauges and overlapping video recordings calibrated along the slope. The effects from lateral hill slope curvature are analyzed: the leading wave crest amplitude generated on a planar hill slope is 3% larger on average than the leading wave crest generated on a convex conical hill slope, while the leading wave trough and second wave crest amplitudes are smaller. The fjord scenario traps the wave energy resulting in the average maximum runup being 10% larger than in the curved headland scenario, which allows some wave energy to leak into the open basin. Between 1-24% of the landslide kinetic energy is transferred in to the wave train. Cobble landslides transfer on average 43% more kinetic energy into the wave train than the gravel landslide. Predictive equations for the offshore and laterally propagating wave and runup amplitudes, periods, celerities and lengths are derived, which allow an initial rapid tsunami hazard assessment. Finally, the predictive wave and runup equations are applied to the 2007 field event in Chehalis Lake, Canada.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2011.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 136-138).
This research develops a Landslide Hazard Rating System for the rainfall-induced landslides in the Chenyulan River basin area in central Taiwan. This system is designed to provide a simplified and quick evaluation of the possibility of landslide occurrence, which can be used for planning and risk management. A systematic procedure to investigate the characterization of rainfall distribution in a regional area is developed in the first part of the thesis. Rainfall data for approximately one decade, 2002 to 2008, from 9 rainfall stations in the study area are included, in which a total of 46 typhoons are selected and categorized into 3 typhoon paths: the Northeastern, Northwestern, and Western. The rainfall distribution affected by typhoon paths in a region is thereby determined. The second part of the thesis is the Landslide Hazard Rating System, which integrates different hazard factors: bedrock geology, aspect, and slope gradients. This analysis is based on the specific characterization of the study area, which consists of the relative topographic relief (aspect and slope gradients) and variable bedrock geology. The method of normalized difference is used for examining the relationship of the topographic features to landslide occurrence. Although this study is conducted in a specific area, this landslide hazard rating system can be applied to other locations. Finally, a concept of a rainfall-induced landslide analytical system is proposed to combine the rainfall distribution analysis and the landslide hazard rating system. This analytical system is intended to include and address the relationship of rainfall and landslide occurrence by combining characterizations of rainfall, topography, and landslide potential. Additionally, this study recommends that, in future work, theoretical models of rainfall distribution and laboratory tests of soil and rock samples be included. Together, these will constitute a basis for the prediction of landslide occurrence. The ultimate goal of future work should be the development of a system for assessing and forecasting rainfall-induced landslide risks, which can become the foundation for a comprehensive risk management system for use in planning.
by Yi-Ting Chen.
S.M.

碩士
國立中興大學
水土保持學系所
100
Typhoon Morakot caused massive collapses in the watersheds which resulted in debris disasters and channel blockages of the nearby villages especially located at the southern Taiwan. Due to scattered distribution of the landslides, how to extract the watershed landslides, find the landslides occur reasons, and monitor the status of watershed’s vegetative restoration can be served as the references of delineating potential landslide areas, assessing the vegetative recovery rate (VRR) and providing the proprity management of the landslides. This study extracted the spatial distribution of landslides and calculated the collapse ratio in Cishan Creek watershed using satellite images before and after the Typhoon event. Besides, the VRR of the watershed was evaluated by applying the image taken a year after the hits of Morakot. The results show that the collapse ratio and VRR of the watershed were 8.07% and 7.24% respectively. The topographic factors of the watershed such as watershed area, watershed perimeter, watershed length, length of mainstream, rivers of total length, number of rivers, elevation, relief, number of headwaters, slope, watershed width, form factor, stream frequency and stream order are employed to study the contributions to the collapse ratio and VRR of the watershed. Among them, the factors of watershed perimeter, number of headwaters, number of rivers, elevation, slope, relief, watershed width and form factor can be classified as categories of scale, gradient, and form three principal component axes, which extract about 83.79% of information and show significant effects on the collapse ratio and VRR of the watershed. The VRR can further be grouped as excellent, ordinary, and poor rates, the collapse ratio be grouped as high, medium and low by K-means, which couples with discriminant analysis can derive Fisher''s linear discriminant function to explore the affecting factors of the collapse ratio and VRR for the watershed landslides. The results indicate that the accuracy of the classification for the collapse ratio and VRR can reach 67.5% and 70%. The topographic factors of a watershed can effectively interpret the potential landslides and VRR. The difference of categories derived from K-means and discriminant analysis can be used as the index of management priority. No. 21, 22, 28, 31, 33及36 are the management compartments which needed to be more concerned in Cishan Creek watershed, and the models developed in this study can be as the references of watershed landslide management.

碩士
清雲科技大學
土木與防災研究所
95
This paper demonstrates the possibility of using resistivity image profiling method (RIP) to monitor a landside at No.3 freeway of 85 km. Several arrays such as the Wenner array, Schlumberger array and Dipole-dipole array were tested the efficiency of the RIP method at different time intervals. The relationship between resistivity and landside can be referred from the resistivity characteristics shown in RIP sections. The results of this study show that the interface between the high resistivity and low resistivity zones. The high resistivity zones around 70-120 Ω-m are classified to be sandstone, while low resistivity zones around 1-10 Ω-m are classified to be mudstone or weathered fractured sandstone saturated with water after a heavy rain. Observations on different types of weather over a long period of time indicate that the resistivity variation underneath the surface did relate to the rainfalls, and it will affect the stability of landside. Time-lapse RIP sections for different time period also indicate that the obvious resistivity change zones were limited under a strongest topography change surface.

This research investigates landside congestion at bulk cargo marine terminals in forestry export supply chains and explores the role of information systems in understanding congestion and mitigating its impacts. Through the conduct of three qualitative case studies supported by quantitative modelling, this research contributes to a more holistic understanding of congestion factors, their interactions, and mechanisms for congestion mitigation at bulk cargo terminals in forestry supply chains. Contemporary approaches to understanding and mitigating congestion, both in the research literature and in practice, have primarily focused on the supply chain's individual components rather than on how these components interact. These approaches are often disconnected from the underlying factors that contribute to the emergence of congestion in the system as a whole and focus on congestion symptoms and their resolution at pinch-points along the supply chain. Many congestion mitigation approaches prioritise technical solutions that address narrowly defined technical, economic and regulatory metrics. For example, digital tools in the form of terminal appointment systems (Huynh, Smith and Harder, 2016; Schulte et al., 2017) and automation technologies (Heilig and Vos, 2017) are regularly promoted to manage congestion. While these tools are undoubtedly useful, their promotion is often primarily for terminal efficiency or cost considerations (Chang Guan and Liu, 2009), in isolation from other factors that may be equally important. More broadly, evidence supporting infrastructure, technology and regulatory instruments as impacting positively on congestion, are too frequently only measured through narrowly defined metrics at specific points in a supply chain exhibiting congestion. This raises questions relating to what extent positive evaluations of congestion mitigation are partly a consequence of shifting the congestion problem to other parts of the supply chain. This issue has remained under-explored, as have the mechanisms through which congestion mitigation approaches are chosen and how their effects are experienced by various stakeholders involved in bulk cargo supply chains. Improving understanding of factors contributing to congestion is important, as is a better understanding of the adoption, use and application of information systems as part of approaches to mitigate the effects of congestion. Two of the most influential and highly cited papers in the domain of landside congestion management are empirical investigations (Giuliano & O'Brien, 2007; Morais & Lord, 2006). The issues highlighted by these papers regarding the ineffectiveness of appointment systems and other congestion mitigation methods in practice have been the primary driver for this work. Although these papers are more than a decade old, the extant research literature has, to date, failed to answer the question of how theoretical benefits derived from congestion mitigation be achieved practice. This research provides enhanced insights into factors contributing to congestion and into mechanisms for its mitigation. The research also presents insights into selecting and calibrating mechanisms to enhance their effectiveness for the entire supply chain. Landside congestion is conceptualised as a 'wicked' problem to sensitise this research to the socio-technical factors and their interactions in forest products export supply chains. 'Wicked' problems as described by Rittel and Webber (1973) are characterised by a plurality of perspectives on the problem, stakeholder objectives and potential problem resolutions. Already research has identified novel technologies such as remote sensing, networked embedded sensors operating in the Internet of Things (IoT) (Scholz et al., 2018), blockchain (Jabbour et al., 2020) artificial intelligence (AI), machine learning and deep learning as well as big data and cloud computing (Muller, Jaeger and Hanewinkel, 2019) are perceived as both disruptors and potential solutions to the many challenges faced by modern supply chains including forestry. However, most research focuses on technical aspects of these technologies and to a lesser extent on understanding of the importance and impact of social and behavioural components. Indeed, whilst there are large numbers of research papers advocating for the use of these novel technologies, few, if any, provide detailed insights into the mechanisms for their implementation or metrics to evaluate their impact on congestion. To address this limitation, this research adopted a participatory design approach to capture the multiple perspectives from the diverse set of supply chain stakeholders grappling with the congestion. More specifically, the participatory design approach used focused on facilitating solution development by participants in ways sensitive to the role of digital tools and techniques along the supply chain (Bodker, Kensing and Simonsen, 2004, 2011). The methodology adopted in this research involved the conduct of three participatory design case studies. Each case study focused on an Australian bulk-cargo marine terminal and its users' supply chains. The research strategy consisted of three stages deploying both qualitative and quantitative data collection and analysis techniques. The three stages were: exploration, design workshops and evaluation. This investigation was underpinned by a subjective ontology and an interpretive epistemology. Using multiple case studies was designed to overcome the perceived shortcomings of a single case concerning generalisability, the causal relations identified (Cavaye, 1996), and the possibility that findings result from case idiosyncrasies (Miles and Huberman, 1994). In terms of research design, Stage 1: Exploration aimed to provide a baseline understanding of the participants' perceptions of congestion factors, implications and potential mitigation mechanisms. During Stage 1: Exploration, qualitative data were collected through 13 site visits and 30 semi-structured interviews. These data were coded using a process drawing on grounded theory principles and led to insights that guided the subsequent stages. Quantitative data consisting of more than 250,000 truck arrival records and over 16,500 truck geo-positioning entries were also collected. These data were analysed in the next stage of the research to prepare the workshops. Stage 2: Design Workshops aimed to capture the joint understanding of the participants' perceptions, facilitate the alignment of perspectives, and develop a common vocabulary among participants. Furthermore, the workshops included a design component in which participants could develop congestion mitigation approaches for their supply chains. Four workshops involving 25 participants across the three case studies were conducted. The quantitative data were analysed using simulation modelling and exploratory data analysis to improve understanding of the impact of stochastic components on the terminal's operational performance and evaluate the truck unloading operations' sensitivity at the terminal to changes in these stochastic components or the terminal setup. The quantitative data analysis results were presented during the workshops and directly contributed to a common understanding of options' implications. The qualitative data emerging from this stage were coded using a process drawing on grounded theory principles. Finally, Stage 3: Evaluation aimed to explore the effectiveness of the participatory design process on the participants' understanding of congestion and where possible, to evaluate the impact of developed and implemented solutions on congestion. It could not be assumed at the outset of the research that the supply chain stakeholders would implement the designs emerging from the workshops. However, when this did occur, the second component of Stage 3: Evaluation aimed to capture the impact of the designs on congestion. Stage 3: Evaluation consisted of 11 semi-structured interviews and approx. 10,000 truck arrival records. Qualitative data from the workshops were also used during Stage 3: Evaluation. This research has been approved by the Human Ethics Research Committee (Tasmania) under ref: H0016718. The key findings of this research pertain to a better, more holistic, understanding of congestion factors, mitigation design alternatives and impact evaluation. The research has also highlighted the utility of a participatory design approach in achieving these results and has explored in detail the role information systems can play in better understanding and mitigating congestion at bulk cargo marine terminals for forest products. KF-1. Social, technical and behavioural factors and processes pertaining to the terminal, the marine- and landside supply chain interact to contribute to the appearance and severity of landside congestion. Therefore, congestion can be considered an 'emergent' property of intersecting supply chains. As a result, congestion mitigation is often perceived to fall outside individual organisations' responsibility. The factors and processes identified in this research include: • limited coordination of logistics flows within organisations, and within and between forest products supply chains, • misaligned incentives within organisations, and within and between forest products supply chains, • excessive interdependence of operations within supply chains and technical limitations to flexibility, • infrastructure capacity or performance limitations • behavioural responses associated with operational disruptions and congestion, • misinterpretation of performance expectations • a plurality of perspectives on congestion within and between supply chains; KF-2. Congestion, particularly with increased recurrence, affects the costs, compliance and fatigue risks of truck operators and creates operational uncertainty and the generation of significant frustration for participants across supply chains. Congestion is not only an operational problem. Failure to conceptualise and respond to congestion as a supply chain problem has consequences for the competitiveness and resilience of individual organisations and supply chains. KF-3. The participatory design approach utilised in this research enhanced the researcher's and participants' understanding of congestion and facilitated the xxii emergence of contextually relevant congestion mitigation mechanisms. A key component of the participatory design approach was the interplay between the qualitative and quantitative data and analysis. Qualitative techniques permitted identifying aspects pertaining to congestion that do not easily lend themselves to quantification. Quantitative techniques allowed the validation of or challenging of participants' perceptions and beliefs underlying their conventional responses to congestion. An outcome of the approach was that the participants designed and implemented mechanisms to mitigate congestion and initiated the deployment of digital tools to support coordination efforts and also attempted to apply by themselves the same approach in other similar circumstances. As a result, the congestion factors previously discussed in KF-1 were identified and congestion was defined as "An emergent symptom of logistics systems, characterised by higher-than-expected delays, generally manifesting at marine terminals, caused by a plurality of factors and their interactions and a multitude of stakeholders' perspectives and associated individual response behaviours". Furthermore, the participants designed and implemented mechanisms to mitigate congestion and investigated the deployment of digital tools to support coordination efforts. These were evaluated, and their positive impact on congestion confirmed. KF-4. Conventional measures for congestion (e.g. average truck turnaround times), used in isolation from other indicators, tend to misrepresent congestion. Performance metrics based solely on average measures may obscure the uncertainty and variability of measurements. Stakeholders may have unrealistic expectations as the average is often confused with the maximum. Congestion mitigation measures aimed at addressing average measures for congestion may, in fact, fail to address congestion even if successful at reducing the average measures. KF-5. Information systems can contribute to better understanding and mitigation of congestion. Exploratory data analysis and simulation modelling highlighted the congestion-related bottlenecks and helped challenge the participants' assumptions on congestion factors and frequency of occurrence. Furthermore, the simulation scenario analyses helped direct the participants' attention towards designing for the most promising congestion mitigation approaches. Information sharing supported the supply chain coordination mechanisms designed by participants. Information sharing, both at the operational and tactical levels pertaining to truck and vessel schedules, was instantiated to enhance coordination between the supply chains intersecting at the terminal. In one case study, the participants also commenced the procurement process for a terminal appointment system to facilitate truck arrivals' coordination at the terminal. The initiation of information sharing was partially contingent on addressing information asymmetry between participants and a mutual definition of each party's behavioural responses following information sharing. KF-6. The participants' perceptions of the expected benefits of digital tools to mitigate congestion were not grounded in evidence or a clear understanding of the mechanisms through which information technology would address congestion. As a result, the way in which technology was adopted and utilised by users was rarely closely correlated to congestion mitigation. Indeed, there were numerous examples of where individual organisations had justified investment in IT tools by reference to landside congestion management but had not subsequently analysed the data produced by these systems or utilised it to address congestion-related challenges proactively. These key results have also led to the production of a model for identifying and understanding interactions among factors contributing to congestion and a framework to support holistic responses to congestion mitigation.

The global shortage of ship officers is an issue receiving increasing attention as shipping companies consider how they will continue to operate their vessels in a safe manner. In particular, the issues of the recruitment of seafarers, their career progression to officer level, and their subsequent turnover due to the ease of mobility within the maritime industry have placed a greater emphasis on retention of this valuable resource. A review of the extant literature reveals that recurring wastage among cadets and senior officers compounds the shortage problem as the number of years spent at sea by the newer generation of ship officers reduces. This indicates the need for a greater understanding of the range of retention issues in order to prolong the number of years that ship officers spend onboard ships. Thus the primary research question for this thesis is: How can shipping industry employers improve the retention of ship officers? This thesis found that the literature tends to pay little attention to the causes of the shortage of ship officers and even less to how it can be effectively addressed. This is also evidenced by a paucity of in-depth conceptual and empirical research focusing on the topic. Thus, this thesis investigates the current shortage of ship officers onboard ships. This is done by (i) identifying the factors predicting the movement of ship officers from ships to landside jobs; (ii) examining the major reasons for the shortage of ship officers; (iii) explaining the attrition process among ship officers; and (iv) assessing whether the strategies being used by shipping industry employers to retain ship officers are effective. To effectively address the primary research question, this thesis uses an explanatory sequential mixed methods research design, consisting of a web-based survey of ship officers and a semi-structured telephone interview of senior managers of shipping industry employers in Australia. The web-based survey was sent to 305 ship officers through key gatekeepers within the Australian shipping industry. In total, 198 responses were received equating to a 65 percent response rate. For the semi-structured phone interviews, the participation of 12 senior managers from a sample size of 20 representing a response rate of 60 percent. The empirical results of the web-based survey of ship officers reveals four categories of factors that demotivate ships officers and consequently predict their turnover. These factors relate to the organisational, extrinsic, personal and industry issues within the environment in which seafarers practise their career. Personal issues account for more than two thirds of the reasons why ship officers may quit working onboard ships to pursue landside opportunities. The strong influence of personal factors on the movement of seafarers from ships to landside jobs signals the need for a greater understanding of the issue among industry employers. Separation from family and home was found to be one of the most important personal issues contributing to high turnover among seafarers. Other aspects of the four categories of factors causing turnover among ship officers are: limited communication with family, lack of opportunities for training and career progression, poor mentorship onboard and dissatisfaction with the employer. Thus, the moving of seafarers from ships to landside jobs is triggered by a combination of issues which may be personal, organisation-based or industry-related. This highlights the multidimensional aspect of the ship officer attrition problem. Consequently, it is very important for Australian shipping industry employers to adopt multiple approaches for the improvement of retention among their seafarers. An analysis of the semi-structured telephone interview transcripts highlights complex retention issues, a lack of adequate training and lapses in industry regulations as the reasons for the shortage of ship officers. It was also found that Australian shipping industry employers mostly rely on high salaries, recreational facilities and good working conditions as strategies to retain their ship officers onboard. Thus this thesis contributes to a reflective understanding of how Australian seafarers perceive their career and also indicates areas that may need to be improved to increase retention rates among ship officers. By combining the findings of both the web-based survey and semi-structured telephone interviews, this thesis advocates that strategies capable of improving the attractiveness of seafaring and working onboard ships must be vigorously pursued by shipping industry employers. From an industry perspective, identifying and having a proper understanding of the factors that make seafaring less attractive is quite necessary to significantly improve the ability of shipping industry employers to attract potential people into a seafaring career. The comments of respondents from the web-based survey instrument suggest the premium placed on training by Australian seafarers. Specifically, financial assistance to complete training schedules is regarded as a key aspect of the support that Australian shipping organisations may need to provide for seafarers. Additionally, this thesis demonstrates the need for a more definite and sustainable career path for seafarers. The key to achieving this is for Australian shipping industry employers to have a well-planned mentorship programme onboard where senior officers can pass their skill, knowledge and operational experience on to cadets and junior officers that may reduce attrition among cadets and other junior officers. The findings of this thesis also has policy implications for shipping companies with regards to the recruitment and retention of ship officers as it identifies key shortcomings within the existing human resource practices of industry employers. This thesis highlights the need for a more responsible approach to the employment of seafarers. In the Australian context, the application of strategic human resource theories to the retention problem is a new approach. Other contributions from this thesis are the differences in the view of seafarers and employers on retention, the use of mixed methods approach and the introduction of the convergence and seafarer turnover models.

碩士
國立臺灣師範大學
地理學系
107
Camping is one of Taiwan’s favorite outdoor activities. According to The Camping Association of the R.O.C., more than 2 million Taiwanese went camping in 2014. The camping activities also have shown a significant growth in 2013, found in Google Trends keyword research tool. However, the development of campground dramatically affect environment, such as decrease of vegetation cover, degradation of soil, and etc. Some campgrounds are located in geologically sensitive areas with high potential of geological hazards, such as landslides and debris flow. In order to know the temporal and spatial changes of campgrounds in recent years, this study used the spatial dataset obtained from the orthophoto of the Aerial Survey Office, Forestry Bureau in 2008, and the images of Google Earth in 2013 and 2017 of north area of Jianshi township, Hsinchu County. The research methods included the dynamic degree of the land use changes, transfer matrix and the Markov process. The transition probability between campgrounds and non-campgrounds were determined by using the amplitude of the land use pattern changes during the three different periods. In addition, Markov model of campgrounds change in this region was established and validated by the transition probability. The characteristics and tendency of campgrounds change were analyzed and forecasted with the Markov model. The results indicated that the growth rate of the campground area from 2008 to 2017 was 745.43%； in terms of the dynamics of land use type, the area of campgrounds from 2008 to 2017 increased by 819,823 m2, the annual rate of change was 82.8%； the transfer matrix showed that a total 893,348 m2 of land was converted to campgrounds, equivalent to a total area of 3.4 Daan Forest Parks, showing the growth of campgrounds between 2008 and 2017. In order to know if the process can predict the future change of land use, the hypothesis used the X2-test. The chi-square goodness-of-fit test indicated that the third mode of this research has better fit, p value is close to 0.05. Therefore, using the average transfer matrix to predict the campground area of 2021. It is estimated that the growth rate of campground area in 2021 will grow by 46.5% compared with 2017, and estimate that the actual area development of campgrounds in 2021 may be greater than the forecast results, but may also change due to the government policy. Due to the research limitations of Markov chain, it is recommended to use Logit regression as a follow-up method in the future. Finally, through the GIS tool, the high-risk landslide disaster of the campgrounds was assessed. In general, this research expected to provides suggestions of a reference for the land use planning in this area.

碩士
逢甲大學
土地管理所
93
This study wanted to know the factors that affected the landside in Shei-Pa National Park and to build the estimation model for the landside collapsion probability by statistic method. This study collected multi-temporal images of SPOT satellite (1993, 1999, 2002, and 2004) and there were earthquake and typhoon occurred in this period. In order to improve the accuracy of image classification from river and collapse, this study calculated the threshold of slope degree from DEM . The result showed that the overall accuracy could be arrived at 90% and the kappa could be arrived at 85%. After that, this study collected RS and GIS factors and used spatial analysis technique to integrate. we used logistic regression to analyzed the data of the first of three periods and built the estimation model for the landside collapsion probability. The result showed that the accuracy of the estimation model was 76% and the import factors were those: the kinds of plant, the quality of soil, the distance from river, and few spectrum indexes. Finally, this study tested the last period data to estimate the landside collapsion and get a good result.