Search results for "ELEVATION"

HIGH-RESOLUTION SURFACE AND BED TOPOGRAPHY MAPPING OF RUSSELL GLACIER (SW GREENLAND) USING UAV AND GPR

2020

Abstract. This study presents the detailed survey of the northern marginal part of Russell Glacier, SW Greenland using the combination of unmanned aerial vehicle (UAV) photogrammetry and low-frequency ground penetrating radar (GPR) measurements. Obtained digital elevation model (DEM) and ice thickness data from GPR data allowed the generation of high precision subglacial topography model. We report uncertainties arising from GPR, GPS, and DEM suggesting sufficient accuracy for the reconstruction of glacier bed topography. GPR data and generated subglacial topography model does not reveal any possible Nye channel that could be incised into the bedrock, however, we were able to detect englaci…

TERRESTRIAL LASER SCANNING FOR COASTAL GEOMORPHOLOGIC RESEARCH IN WESTERN GREECE

2012

We used terrestrial laser scanning (TLS) for (i) accurate volume estimations of dislocated boulders moved by high-energy impacts and for (ii) monitoring of annual coastal changes. In this contribution, we present three selected sites in Western Greece that were surveyed during a time span of four years (2008-2011). The Riegl LMS-Z420i laser scanner was used in combination with a precise DGPS system (Topcon HiPer Pro). Each scan position and a further target were recorded for georeferencing and merging of the point clouds. For the annual detection of changes, reference points for the base station of the DGPS system were marked. Our studies show that TLS is capable to accurately estimate volu…

Predicting storm-triggered debris flow events: application to the 2009 Ionian Peloritan disaster (Sicily, Italy)

2015

Abstract. The main assumption on which landslide susceptibility assessment by means of stochastic modelling lies is that the past is the key to the future. As a consequence, a stochastic model able to classify past known landslide events should be able to predict a future unknown scenario as well. However, storm-triggered multiple debris flow events in the Mediterranean region could pose some limits on the operative validity of such an expectation, as they are typically resultant of a randomness in time recurrence and magnitude and a great spatial variability, even at the scale of small catchments. This is the case for the 2007 and 2009 storm events, which recently hit north-eastern Sicily …

Estimation of synthetic flood design hydrographs using a distributed rainfall–runoff model coupled with a copula-based single storm rainfall generator

2014

Abstract. In this paper a procedure to derive synthetic flood design hydrographs (SFDH) using a bivariate representation of rainfall forcing (rainfall duration and intensity) via copulas, which describes and models the correlation between two variables independently of the marginal laws involved, coupled with a distributed rainfall–runoff model, is presented. Rainfall–runoff modelling (R–R modelling) for estimating the hydrological response at the outlet of a catchment was performed by using a conceptual fully distributed procedure based on the Soil Conservation Service – Curve Number method as an excess rainfall model and on a distributed unit hydrograph with climatic dependencies for the …

A Self-Contained and Automated Method for Flood Hazard Maps Prediction in Urban Areas

2020

Water depths and velocities predicted inside urban areas during severe storms are traditionally the final result of a chain of hydrologic and hydraulic models. The use of a single model embedding all the components of the rainfall&ndash

What makes segmentation good? A case study in boreal forest habitat mapping

2013

Segmentation goodness evaluation is a set of approaches meant for deciding which segmentation is good. In this study, we tested different supervised segmentation evaluation measures and visual interpretation in the case of boreal forest habitat mapping in Southern Finland. The data used were WorldView-2 satellite imagery, a lidar digital elevation model (DEM), and a canopy height model (CHM) in 2 m resolution. The segmentation methods tested were the fractal net evolution approach (FNEA) and IDRISI watershed segmentation. Overall, 252 different segmentation methods, layers, and parameter combinations were tested. We also used eight different habitat delineations as reference polygons agains…

Characteristics of patients from the Polish Registry of Acute Coronary Syndromes during the COVID-19 pandemic: the first report

2021

Utilidad de la troponina I para predecir la disfunción sistólica en los síndromes coronarios agudos. Resultados de un estudio prospectivo y cuantitat…

2003

The relationship between troponin I and systolic function (quantitative contrast ventriculography) was evaluated in 137 consecutive patients with a first acute coronary syndrome (60 with and 77 without ST elevation). In general, a larger troponin I peak value was related with a more depressed ejection fraction and poorer regional systolic function (p < 0.0001). Nevertheless, this correlation was weaker than expected, especially in those cases without ST-segment elevation, suggesting that other factors apart from systolic dysfunction must be taken into account in order to explain the worse prognosis of those patients with increased serum levels of this marker of myocardial damage.

Why does C-reactive protein increase in non-ST elevation acute coronary syndromes?

2003

Abstract Introduction: C-reactive protein is an important prognostic indicator for early risk stratification in patients with an acute coronary syndrome. The mechanisms underlying the elevation of C-reactive protein in these patients have not been fully understood. We studied the factors related to the increase of this acute-phase reactant. Methods and Results: Within a single-centre registry, 419 consecutive patients admitted for a non-ST elevation acute coronary syndrome were studied. Serum high sensitivity C-reactive protein was measured late (median 3 days) after admission. Clinical, electrocardiographic, biochemical and angiographic variables were recorded. In the multivariate analysis…

Is neural network better than logistic regression in death prediction in patients after ST-segment elevation myocardial infarction?

2021

Background: There is a need to develop patient classification methods to adjust post-discharge care, improving survival after ST-segment elevation myocardial infarction (STEMI). Aims: The study aimed to determine whether a neural network (NN) is better than logistic regression (LR) in mortality prediction in STEMI patients. Material and methods: The study included patients from the Polish Registry of Acute Coronary Syndromes (PL-ACS). Patients with the first anterior STEMI treated with the primary percutaneous coronary intervention (pPCI) of the left anterior descending (LAD) artery between 2009 and 2015 and discharged alive were included in the study. Patients were randomly divided into th…