The simple accumulation-based network identification method (ANIM) in a raster Geographic Information System (GIS) posed by O'Callaghan and Mark (1984) has been criticized for producing a spatially uniform drainage density (Tarboton 2002) at the watershed scale. This criticism casts doubt on the use of ANIMs for deriving properties such as overland flow length for nonpoint source pollution models, without calibrating the accumulation threshold value. However, the basic assumption that underlies ANIMs is that convergent topography will yield a more rapid accumulation of cells, and thus, more extensive flow networks, with divergent, or planar terrain yielding sparser networks. Previous studies have focused on networks that are coarser than the hill-slope scale, and have relied upon visual inspection of drainage networks to suggest that ANIMs lack the ability to produce diverse networks. In this study overland flow lengths were calculated on a sub-watershed basis, with standard deviation, and range calculated for sub-watershed populations as a means of quantifying the diversity of overland flow lengths produced by ANIM at the hill slope scale. Linear regression and Spearman ranking analyses were used to determine if the methods represented trends in overland flow length as suggested by manual delineation of contour lines. Three ANIMs were analyzed: the flow accumulation method (O'Callaghan and Mark, 1984), the terrain curvature method (Tarboton, 2000) and the ridge accumulation method (introduced in this study). All three methods were shown to produce non-zero standard deviations and ranges using a single support area threshold, with the terrain curvature method producing the most diverse networks, followed by the ridge accumulation method, and then the flow accumulation method. At an analysis unit size of 20 ha, the terrain curvature method produced a standard deviation that was most similar to those suggested by the contour crenulations, -13.5%, followed by the ridge accumulation method, -21.5%, and the flow accumulation method, -61.6%. The ridge accumulation produced the most similar range, -19.1%, followed by terrain curvature, -24.9%, and flow accumulation, -65.4%. While the flow accumulation networks had a much narrower range of predicted flow lengths, it had the highest Spearman ranking coefficient, Rs=0.722, and linear regression coefficient, R2=0.602. The terrain curvature method was second, Rs=0.641, R2=0.469, and then ridge accumulation, Rs=0.602, R2=0.490. For all methods, as threshold values were varied, areas of dissimilar morphology (as evidenced by the common stream metric stream frequency) experienced changes in overland flow lengths at different rates. This results in an inconsistency in ranking of sub-watersheds at different thresholds. When thresholds were varied to produce average overland flow lengths from 75 m to 150 m, the terrain curvature method showed the lowest incidence of rank change, 16.05%, followed by the ridge accumulation method, 16.73%, then flow accumulation, 25.18%. The results of this investigation suggest that for all three methods, a causal relationship exists between threshold area, underlying morphology, and predicted overland flow length. This causal relationship enables ANIMs to represent contour network trends in overland flow length with a single threshold value, but also results in the introduction of rank change error as threshold values are varied. Calibration of threshold value (varying threshold in order to better match observed overland flow lengths) is an effective means of increasing the accuracy of ANIM predictions, and may be necessary when comparing areas with different stream frequencies. It was shown that the flow accumulation method produces less diverse networks than the terrain curvature and ridge accumulation methods. However, the results of rank and regression analyses suggest that further investigation is required to determine if these more diverse ANIM are in fact more accurate than the flow accumulation method. / Master of Science

Environmental concerns are becoming increasingly relevant during a period of hemorrhaging ecosystem goods and services. Restoring these would result in positive outcomes for public health and economic benefit. This thesis seeks to address two environmental concerns: (1) accurate soil mapping and (2) treatment of nitrogen to affect water quality change.The current method of soil mapping, SSURGO (USDA‐NRCS Soil survey), is often erroneous and misleading. Two studies in this dissertation are conducted to evaluate the potential that different resolution digital elevation models (DEMs) have to distribute soil characteristics successfully. These studies are conducted in southwest Virginia and western Vermont. The aforementioned studies evaluated 36 and 59 soil samples, respectively. Spatial characteristics, including slope, catchment area, and topographic wetness, are derived from several DEMs. In chapter 2, these characteristics are spatially compared, and we found that small resolution rasters result in narrow flow paths relative to coarser rasters. In chapter 3, we isolate the analysis to focus on resolution size, instead of a mix of both resolution size and generation method. This is done by recursively coarsening small rasters, deriving spatial attributes from said rasters and evaluating their potential to fit the soil characteristics of interest. Here we found that slopes generated from resolutions smaller than 11m were poor predictors of soil characteristics. Both chapters are finished by proposing and evaluating a soil map. Proposed regressions beat SSURGO in all investigated properties. Furthermore, proposed maps consistently beat out uninformed smallest resolution derived maps.Chesapeake bay water quality managers are struggling to achieve targets for nitrogen loading. This is in part due to the widespread presence of legacy nitrogen. Legacy nitrogen is an emerging issue, and springs exporting high levels of nitrogen are not uncommon in northern Virginia. This thesis explores, in part, a novel concept of treating large loads of nitrogen exported from a spring with a bioreactor. Bioreactors are a young science that most typically pair carbon heavy subterranean receptacles to agricultural drainage. This provides a location for nitrogen fixing bacteria to consume nitrate/nitrite, turning these into inert nitrogen gas. A spring fed bioreactor is studied for 10 months, and bioreactor conditions including influent and effluent nitrogen concentrations, bioreactor flow, and temperature are collected. A model driven by first order reaction equations is found to be most accurate with inputs of temperature and bioreactor age. The resulting marginal effects of these inputs were consistent with previously reported studies. / Doctor of Philosophy / Centuries of industrialization have resulted in widespread human progress but have, at times, adversely impacted the environment. Constituents rely heavily on environmental services, such as clean air and water, to subsist. Environmental degradation has resulted in detrimental effects to public health, and remediation is currently economically viable. As such, there are strong incentives for researchers to understand environmental processes at a fundamental level. One such process is soil characteristic distribution. The distribution of soil characteristics, such as soil texture or organic matter, is especially important for agriculturalists, hydrologists and geotechnicians. Soil texture and organic matter distribution can affect crop yield, nitrogen export to surface waters, and structural stability of soils. Thus, accurate characterization of measured soil properties is paramount to multiple fields. The most typically used soil map is USDA‐NRCS Soil survey (commonly referred to as SSURGO). Currently, the SSURGO database is a poor predictor of soil characteristics. There is an opportunity to improve soil characteristic distribution using digital elevation models (DEMs). As DEMs become cheaper to develop, they are typically available in multiple resolutions and generation methods. In this research, several DEMs are used to better soil maps for watersheds in Southwest Virginia and Western Vermont. Both studies showed that DEMs can better distribute soils when compared to the current SSURGO maps. Additionally, we showed that the finest resolution dataset was not always best, and mixed resolution topographic wetness indices to be most advantageous for distributing soils.Another such process is remediation of surface waters from high loads of nitrogen and phosphorus. The Haber-Bosch method of producing nitrogen fertilizer is one of the most important human innovations in recent history. This method is likely responsible for the aversion of widespread famine in the early 1900s. However, residents of multiple river systems, including the Chesapeake Bay and the Mississippi River, are suffering from the adverse effects of widespread hypoxic/anoxic (with little/no oxygen, respectively) zones within water. These have partially been responsible for the decline of commercial ventures such as fisheries and tourism. These zones are caused by eutrophication, a process of unsustainable plant growth in the presence of nitrogen and phosphorus. Water quality managers typically target agricultural runoff and point source polluters when trying to eliminate anthropogenic nitrogen. However, legacy nitrogen (nitrogen stored in groundwater in excess of a year) has become an emerging concern for water quality. It is not uncommon for springs in karst areas to be contaminated with high concentrations of nitrogen. These springs present a point source that can be treated by an emerging technology: bioreactors. Bioreactors are subterranean, woodchip filled basins that provide a location for microbes to exchange water soluble nitrogen for inert nitrogen gas. The consistency in nitrogen loading and constant flow provide stability relative to more traditional bioreactor installations. Most typically, bioreactors are installed downstream of agricultural drainage systems, and influent flow and nitrogen load depend wholly on precipitation/irrigation and nitrogen application. In this thesis, a novel spring fed bioreactor is studied. Removal rates of nitrogen are quantified using a regression driven by reaction kinetics. The analysis showed bioreactor efficiency was intimately related to hydraulic residence time, nitrogen loading, bioreactor bed temperature, and bioreactor age. The spring fed bioreactor is found to be advantageous because of its consistency, and disadvantages because springs are colder and thus less efficient than typical irrigated runoff.

Many Climate Scientists believe that global warming will produce more extreme weather events such as tropical storms, hurricanes, intense rainfall, and flooding. These events are considered to be the most catastrophic natural events for transportation systems especially in coastal areas. Due to the severe damage from storm surge and flooding. Evaluating the magnitude of possible storm surges and their impacts on transportation systems in coastal areas is fundamental to developing adaptation plans and impact assessments to mitigate the damage. This thesis focuses on existing transportation systems in the Georgia coastal area that could be affected by several storm surges. An existing storm surge model is used to estimate the storm surges and the surge heights based on the category, direction, and forward speed of a storm. The ground elevation of the ports, interstates, state roads, railroads, and the principal airports on the Georgia coast are identified through a GIS analysis using the national elevation data set. Having the storm surge elevation and the elevation of the existing infrastructure, a GIS study is performed to identify those parts of the transportation system that will be affected by each type of storm giving results such as the length or sections of transportation assets under or above the surge elevation. A literature review of storm surge, rising sea levels, and their impacts on coastal bridges, roads, airports, ports, and railroads is presented in the thesis. Also, a description of the software used to analyze and estimate the impacts of climate change on transportation systems is described.

Soil is one of the most precious resources on Earth because of its role in storing and recycling water and nutrients essential for life, providing a variety of ecosystem services. This vulnerable resource is at risk from degradation by erosion, salinity, contamination and other effects of mismanagement. Information from soil is therefore crucial for its sustainable management. While the demand for soil information is growing, the quantity of data collected in the field is reducing due to financial constraints. Digital Soil Mapping (DSM) supports the creation of geographically referenced soil databases generated by using field observations or legacy data coupled, through quantitative relationships, with environmental covariates. This enables the creation of soil maps at unexplored locations at reduced costs. The selection of an optimal scale for environmental covariates is still an unsolved issue affecting the accuracy of DSM. The overall aim of this research was to explore the effect of spatial scale alterations of environmental covariates in DSM. Three main targets were identified: assessing the impact of spatial scale alterations on classifying soil taxonomic units; investigating existing approaches from related scientific fields for the detection of scale patterns and finally enabling practitioners to find a suitable scale for environmental covariates by developing a new methodology for spatial scale analysis in DSM. Three study areas, covered by detailed reconnaissance soil survey, were identified in the Republic of Ireland. Their different pedological and geomorphological characteristics allowed to test scale behaviours across the spectrum of conditions present in the Irish landscape. The investigation started by examining the effects of scale alteration of the finest resolution environmental covariate, the Digital Elevation Model (DEM), on the classification of soil taxonomic units. Empirical approaches from related scientific fields were subsequently selected from the literature, applied to the study areas and compared with the experimental methodology. Wavelet analysis was also employed to decompose the DEMs into a series of independent components at varying scales and then used in DSM analysis of soil taxonomic units. Finally, a new multiscale methodology was developed and evaluated against the previously presented experimental results. The results obtained by the experimental methodology have proved the significant role of scale alterations in the classification accuracy of soil taxonomic units, challenging the common practice of using the finest available resolution of DEM in DSM analysis. The set of eight empirical approaches selected in the literature have been proved to have a detrimental effect on the selection of an optimal DEM scale for DSM applications. Wavelet analysis was shown effective in removing DEM sources of variation, increasing DSM model performance by spatially decomposing the DEM. Finally, my main contribution to knowledge has been developing a new multiscale methodology for DSM applications by combining a DEM segmentation technique performed by k-means clustering of local variograms parameters calculated in a moving window with an experimental methodology altering DEM scales. The newly developed multiscale methodology offers a way to significantly improve classification accuracy of soil taxonomic units in DSM. In conclusion, this research has shown that spatial scale analysis of environmental covariates significantly enhances the practice of DSM, improving overall classification accuracy of soil taxonomic units. The newly developed multiscale methodology can be successfully integrated in current DSM analysis of soil taxonomic units performed with data mining techniques, so advancing the practice of soil mapping. The future of DSM, as it successfully progresses from the early pioneering years into an established discipline, will have to include scale and in particular multiscale investigations in its methodology. DSM will have to move from a methodology of spatial data with scale to a spatial scale methodology. It is now time to consider scale as a key soil and modelling attribute in DSM.

Two ceramic vessels of the Öland and Gotland type were in the summer of 2016 discovered at an archaeological excavation at the island of Gotland in the Baltic sea. They were produced with two different techniques of firing, resulting in two different colors of the surface of the pot. Ceramic vessels of the Öland and Gotland type dating from the Roman Iron Age are supposed to have been produced at these islands, but thin-section analysis of pottery found in Mälardalen in the mainland of Sweden show that at least some vessels are made of clay from Mälardalen. The type is distinct and differs both in form and composition of the clay from other ceramic vessels of more ordinary character. This type of ceramic vessel is supposed to be inspired of bronze vessels from the Roman Empire and ceramic vessels from both the Roman Empire and the Celtic area. In this thesis, the aim is to shed some light on the characters of this type of vessel with comparative and empirical studies of pots from Öland and Gotland. This is done by comparing vessels and described graves on the two islands. And for references a few pots from mainland Sweden is also studied. Is it possible to understand why the high-status pottery on Öland and Gotland differ from the rest of the Swedish mainland? Clearly, the wealth of the population on the islands was over average if we measure it in objects of foreign origin, compared with the Swedish mainland. Objects from the Roman Empire such as drinking equipment made of bronze and gold and silver coins made its way to the islands in bigger quantities than to rest of Scandinavia with exceptions from some local areas on the Swedish mainland. / • Vad exakt är en ölandskruka? • Varför finns en det en klar urskiljbar skillnad mellan den keramik vi kallar ölandskrukor/gotlandskrukor jämfört med andra kärl från samma period? • Vad kan dekor och utformning ha inspirerats av? • Är det klara skillnader mellan Öland och Gotland när det gäller ölandskrukorna, eller ser de lika ut på de båda öarna?Den kärltyp av keramik från romersk järnålder som vanligen kallas ölandskruka eller gotlandskruka i rapporter, litteratur eller andra arkeologiska sammanhang är vanlig i det öländska och gotländska materialet. Den hittas företrädesvis i gravar men även andra kontexter förekommer. Kärlen förekommer även sparsamt på det svenska fastlandet och hittas även där i gravar. Det är i de gravar som är rikast på föremål som den oftast påträffas och det pekar på att den är knuten till de personer i samhället som har högst social rang. Andra föremål som hittas tillsammans med ölandskrukor varierar en del mellan Öland och Gotland. Ett exempel på det är bronsskållor som mest är en gotländsk företeelse och endast förekommer sparsamt i det öländska materialet. Dryckeshorn i gravar är vanligast på Gotland och de förekommer ofta i gravar med sländtrissor. På Öland är det i kvinnogravarna vanligt att det förekommer krumknivar i samma grav som ölandskrukor medan mansgravarna ofta är så kallade vapengravar. Vapengravarna på Öland innehåller som regel ett svärd, minst en lansspets och en spjutspets men även fler förekommer, en sköld och en kniv.   Kärltypen som kallas ölandskruka är av tunt gods som glättats på ytan och oftast dekorerats med punktlinjer på den övre delen av skuldran. De är brända i en reducerad atmosfär som ger en svart yta på kärlet. I denna uppsats förekommer även en annan kärltyp med fyra stycken öron på skuldran, dessa kärl förefaller vara brända i en oxiderad atmosfär vilket istället resulterar i en brun eller rödbrun färg på ytan. Förutom dessa två kärltyper förekommer också kannor, de har en hank att hålla i när man häller och är i stort sett alltid dekorerade. Denna dekoration består ofta av olika fält på övre delen av kannan indelade i romber av linjer. I fälten finns olika stämpelmönster, till exempel cirklar, kryss, blomformade och trisklar. Kärlen är så kallad finkeramik som sannolikt inte användes till vardagligt bruk utan som serveringskärl vid till exempel gästabud och som gravgåvor i form av ett uppdukat bord till den avlidne. I en del fall även som benbehållare efter kremering. De kärl som betecknas som finkeramik förefaller ha använts till dryckesritualer och som serviser under gästabud. Även seden att ge den begravde ett dukat bord pekar på att kärlens betydelse var välkänd i det samtida samhället (Eriksson 2009:176ff). Ölandskrukorna introduceras i Mälardalsregionen under äldre romersk järnålder, men företrädesvis i elitmiljöer. Att det även på Öland och Gotland handlar om elitens föremål syns i gravmaterialet, då det är de gravar som är rikast på föremål som även har ölandskrukor, gotlandskrukor eller kannor (se bilaga 1 & 2). Inspirationen till kärlen kan vara bronssitulor som importeras till Skandinavien under denna period (Eriksson 2009:176ff). Den polerade ytan på keramik som förekommer under bronsåldern i Mälardalen försvinner under förromersk järnålder och den tidigaste återkomsten av polerad keramik i området dateras till tiden efter Kristi födelse (Eriksson 2009:127). Dessa kärl har en svartglänsande yta som mycket väl kan tänkas föreställa eller efterlikna metall. Liknande former på kärl har bland annat hittas i tidigare nämnda Gödåker där ett kärl har en dekor som är klart inspirerad av samtida metallkonst. Det kan även finnas kopplingar till dryckesglas eftersom en del kärl har imitation av slipade glasfacetter. Mellan Öland och Gotland finns en del skillnader i utformningen på kärlen. På Öland är foten på ölandskrukorna mindre eller saknas. Eftersom tillverkningsort för ölandskrukorna inte har kunnat fastställas i nuläget är det svårt att peka på om det beror på att ölänningarna har en annan utformning på sina kärl än gotlänningarna eller om det förekommer variationer i båda regionerna som sedan distribuerats olika.

The main objective of the diploma thesis is creation of methodology and automatization of calibration process of network graph based on the values of morphometric characteristics and motion vectors. The resulting morphometric values of the terrain have been detected on the basis of mathematical and cartographic methods for line course expression. The most accurate one has been used in GIS network analysis over the road network and digital terrain models, which were chosen as the most appropriate for this purpose. Relationship between morphometric values and values suitable for use in network analysis (speed, time, ...) has been studied using specific examples in appropriately selected territory with using selected vehicle, which was designated as a bicycle. The practical part for the verification of functionality of the suggested methodology has been compared with other models of accessibility, available web-map portals and route planners. The process of transport network evaluation based on selected parameters has been automated in Python programming language as a tool in ArcGIS software, which is attached to the diploma thesis. Powered by TCPDF (www.tcpdf.org)

This thesis considers the problem of tracking an object in world coordinates using measurements obtained from multiple uncalibrated cameras. A general approach to track the location of a target involves different phases including calibrating the camera, detecting the object's feature points over frames, tracking the object over frames and analyzing object's motion and behavior. The approach contains two stages. First, the problem of camera calibration using a calibration object is studied. This approach retrieves the camera parameters from the known locations of ground data in 3D and their corresponding image coordinates. The next important part of this work is to develop an automated system to estimate the trajectory of the object in 3D from image sequences. This is achieved by combining, adapting and integrating several state-of-the-art algorithms. Synthetic data based on a nearly constant velocity object motion model is used to evaluate the performance of camera calibration and state estimation algorithms.

This thesis presents the development of a surveillance testbed using wireless sensors and video cameras for vehicle detection and tracking. The experimental study includes testbed design and discusses some of the implementation issues in using wireless sensors and video cameras for a practical application. A group of sensor devices equipped with light sensors are used to detect and localize the position of moving vehicle. Background subtraction method is used to detect the moving vehicle from the video sequences. Vehicle centroid is calculated in each frame. A non-linear minimization method is used to estimate the perspective transformation which project 3D points to 2D image points. Vehicle location estimates from three cameras are fused to form a single trajectory representing the vehicle motion. Experimental results using both sensors and cameras are presented. Average error between vehicle location estimates from the cameras and the wireless sensors is around 0.5ft.

Cardiovascular disease is the leading cause of death worldwide and ischemic heart disease is the most common manifestation. Despite improved outcomes during the last decades, patients with acute coronary syndromes (ACS) are still at substantial risk of recurrent ischemic events and mortality. The aims of this thesis were to investigate the effect of the novel antiplatelet agent ticagrelor versus clopidogrel in patients with non-ST-elevation ACS (NSTE-ACS), overall and in relation to initial revascularization, and to explore this effect in relation to cardiac biomarkers. The impact of timing of revascularization in non-ST-elevation myocardial infarction (NSTEMI) was also studied, by assessing risk of mortality and recurrent myocardial infarction in relation to delay of percutaneous coronary intervention (PCI) in a nation-wide cohort. Finally, a novel clinical prediction model based on angiographic findings, biomarkers, and clinical characteristics was developed to estimate risk of ischemic events after performed revascularization. Ticagrelor treatment compared with clopidogrel was associated with a reduction in the composite endpoint of cardiovascular death/myocardial infarction/stroke and mortality alone, without any increase in overall major bleeding, but increased non-CABG-related major bleeding. The effect of ticagrelor over clopidogrel was consistent independent of initial revascularization. Elevated high-sensitivity cardiac troponin-T predicted benefit of ticagrelor over clopidogrel, while no difference between treatments was detected at normal levels. In patients with NSTEMI, PCI treatment within two days after hospital admission was associated with lower risk of all-cause death and recurrent myocardial infarction compared with delayed PCI. The new clinical prediction model included the following variables: prior vascular disease, extent of coronary artery disease, level of N-terminal pro-B-type natriuretic peptide and estimated glomerular filtration rate; and showed good discriminatory ability for the risk prediction of cardiovascular death/myocardial infarction/stroke and cardiovascular death alone. In conclusion, these results show that ticagrelor reduces the risk of recurrent ischemic events and mortality in patients with NSTE-ACS when compared with clopidogrel, and this effect seems independent of performed revascularization. The results also indicate that biomarkers could be used to select patients who would benefit most from more intense platelet inhibition. Furthermore, early PCI in NSTEMI seems to be associated with improved outcome. Finally, the novel clinical prediction model based only on four variables showed good discriminatory ability, which makes it a potentially effective and simple tool for tailored treatment based on individual risk of recurrent events.

A dissertation submitted to the Faculty of Health Sciences, University of the Witwatersrand, in fulfillment of the degree of Master of Science in Medicine, 2014 / The earliest possible initiation of reperfusion therapy is necessary to reduce morbidity and mortality from acute STEMI. Therefore improving the time to thrombolysis where percutaneous coronary interventional facilities are limited or do not exist is critical. The most effective system would integrate three key components to deliver continuous patient care, including: 1) from time of call for help through to emergency response; 2) transportation to and admission to hospital; 3) assessment and initiation of thrombolytic therapy. The purpose of this prospective study is: to develop a chest pain awareness education programme appropriate for the South African context; to assess safe initiation of thrombolytic therapy by emergency care practitioners for STEMI; and to compare the performance of emergency care practitioner thrombolysis with historical control data.