Multi-resolution image analysis for vehicle detection

Proceeding of: Second Iberian Conference, IbPRIA 2005, Estoril, Portugal, June 7-9, 2005Computer Vision can provide a great deal of assistance to Intelligent Vehicles. In this paper an Advanced Driver Assistance Systems for Vehicle Detection is presented. A geometric model of the vehicle is defined where its energy function includes information of the shape and symmetry of the vehicle and the shadow it produces. A genetic algorithm finds the optimum parameter values. As the algorithm receives information from a road detection module some geometric restrictions can be applied. A multi-resolution approach is used to speed up the algorithm and work in realtime. Examples of real images are shown to validate the algorithm.Publicad

Propagation and transformation of upper North Atlantic deep water from the subpolar gyre to 26.5°N

Because new observations have revealed that the Labrador Sea is not the primary source for waters in the lower limb of the Atlantic Meridional Overturning Circulation (AMOC) during the Overturning in the Subpolar North Atlantic Programme (OSNAP) period, it seems timely to re‐examine the traditional interpretation of pathways and property variability for the AMOC lower limb from the subpolar gyre to 26.5°N. In order to better understand these connections, Lagrangian experiments were conducted within an eddy‐rich ocean model to track upper North Atlantic Deep Water (uNADW), defined by density, between the OSNAP line and 26.5°N as well as within the Labrador Sea. The experiments reveal that 77% of uNADW at 26.5°N is directly advected from the OSNAP West section along the boundary current and interior pathways west of the Mid‐Atlantic Ridge. More precisely, the Labrador Sea is a main gateway for uNADW sourced from the Irminger Sea, while particles connecting OSNAP East to 26.5°N are exclusively advected from the Iceland Basin and Rockall Trough along the eastern flank of the Mid‐Atlantic Ridge. Although the pathways between OSNAP West and 26.5°N are only associated with a net formation of 1.1 Sv into the uNADW layer, they show large density changes within the layer. Similarly, as the particles transit through the Labrador Sea, they undergo substantial freshening and cooling that contributes to further densification within the uNADW layer

Regional Imprints of Changes in the Atlantic Meridional Overturning Circulation in the Eddy-rich Ocean Model VIKING20X

A hierarchy of global 1/4° (ORCA025) and Atlantic Ocean 1/20° nested (VIKING20X) ocean/sea-ice models is described. It is shown that the eddy-rich configurations performed in hindcasts of the past 50–60 years under CORE and JRA55-do atmospheric forcings realistically simulate the large-scale horizontal circulation, the distribution of the mesoscale, overflow and convective processes, and the representation of regional current systems in the North and South Atlantic. The representation, and in particular the long-term temporal evolution, of the Atlantic Meridional Overturning Circulation (AMOC) strongly depends on numerical choices for the application of freshwater fluxes. The interannual variability of the AMOC instead is highly correlated among the model experiments and also with observations, including the 2010 minimum observed by RAPID at 26.5° N pointing at a dominant role of the forcing. Regional observations in western boundary current systems at 53° N, 26.5° N and 11° S are explored in respect to their ability to represent the AMOC and to monitor the temporal evolution of the AMOC. Apart from the basin-scale measurements at 26.5° N, it is shown that in particular the outflow of North Atlantic Deepwater at 53° N is a good indicator of the subpolar AMOC trend during the recent decades, if the latter is provided in density coordinates. The good reproduction of observed AMOC and WBC trends in the most reasonable simulations indicate that the eddy-rich VIKING20X is capable in representing realistic forcing-related and ocean-intrinsic trends

Trace Metal Chemistry in the Water Column of the Angola Basin - A Contribution to the International GEOTRACES Program - Cruise No. M121, November 22, – December 27, 2015, Walvis Bay (Namibia) – Walvis Bay (Namibia)

Meteor Cruise M121 was dedicated to the investigation of the distribution of dissolved and particulate trace metals and their isotopic compositions (TEIs) in the full water column of the Angola Basin and the northernmost Cape Basin. A key aim was to determine the driving factors for the observed distributions, which includes the main external inputs, as well as internal cycling and ocean circulation. The research program of the cruise is official part of the international GEOTRACES program (www.geotraces.org) and cruise M121 corresponds to GEOTRACES cruise GA11. Subject of the cruise was the trace metal clean and contamination-free sampling of waters and particulates for subsequent analyses of the TEIs in the home laboratories of the national and international participants. Besides a standard rosette for the less contaminant prone metals, trace metal clean sampling was realized by using for the first time a new dedicated, coated trace metal clean rosette equipped with Teflon-coated GO-FLO bottles operated via a plastic coated cable from a mobile winch of GEOMAR Kiel. The particulate samples were collected under trace metal clean conditions using established in-situ pump systems operated from Meteor’s Aramid line. The cruise track led from Walvis Bay northwards along the West African margin until 3°S, then turned west until the Zero Meridian, which was followed southwards until 30°S. Then the cruise track turned east again until the Namibian margin was reached and then completed the near shore track northwards until Walvis Bay. The track crossed areas of major external inputs including dust from the Namib Desert and exchange with the west African continental margin and with the oxygen depleted shelf sediments of the Benguela upwelling, as well as with the plume of the Congo outflow, that was followed from its mouth northwards. Our investigations of internal cycling included the extremely high productivity associated with the Benguela Upwelling and the elevated productivity of the Congo plume contrasting with the extremely oligotrophic waters of the southeastern Atlantic Gyre. The links between TEI biogeochemistry and the nitrogen cycle forms an important aspect of our study. The major water masses contributing the Atlantic Meridional Overturning Circulation were sampled in order to investigate if particular TEI signatures are suitable as water mass tracers, in particular near the ocean margin and in the restricted deep Angola Basin. A total of 51 full water column stations were sampled for the different dissolved TEIs, which were in most cases accompanied by sampling for particulates and radium isotopes using the in-situ pumps. In addition, surface waters were continuously sampled under trace metal clean conditions using a towed fish and aerosol and rain samples were continuously collected

The impact of diabetes on the pathogenesis of sepsis

Diabetes is associated with an increased susceptibility to infection and sepsis. Conflicting data exist on whether the mortality of patients with sepsis is influenced by the presence of diabetes, fuelling the ongoing debate on the benefit of tight glucose regulation in patients with sepsis. The main reason for which diabetes predisposes to infection appears to be abnormalities of the host response, particularly in neutrophil chemotaxis, adhesion and intracellular killing, defects that have been attributed to the effect of hyperglycaemia. There is also evidence for defects in humoral immunity, and this may play a larger role than previously recognised. We review the literature on the immune response in diabetes and its potential contribution to the pathogenesis of sepsis. In addition, the effect of diabetes treatment on the immune response is discussed, with specific reference to insulin, metformin, sulphonylureas and thiazolidinediones

Feasibility of digital contact tracing in low-income settings – pilot trial for a location-based DCT app

Abstract Background Data about the effectiveness of digital contact tracing are based on studies conducted in countries with predominantly high- or middle-income settings. Up to now, little research is done to identify specific problems for the implementation of such technique in low-income countries. Methods A Bluetooth-assisted GPS location-based digital contact tracing (DCT) app was tested by 141 participants during 14 days in a hospital in Monrovia, Liberia in February 2020. The DCT app was compared to a paper-based reference system. Hits between participants and 10 designated infected participants were recorded simultaneously by both methods. Additional data about GPS and Bluetooth adherence were gathered and surveys to estimate battery consumption and app adherence were conducted. DCT apps accuracy was evaluated in different settings. Results GPS coordinates from 101/141 (71.6%) participants were received. The number of hours recorded by the participants during the study period, true Hours Recorded (tHR), was 496.3 h (1.1% of maximum Hours recordable) during the study period. With the paper-based method 1075 hits and with the DCT app five hits of designated infected participants with other participants have been listed. Differences between true and maximum recording times were due to failed permission settings (45%), data transmission issues (11.3%), of the participants 10.1% switched off GPS and 32.5% experienced other technical or compliance problems. In buildings, use of Bluetooth increased the accuracy of the DCT app (GPS + BT 22.9 m ± 21.6 SD vs. GPS 60.9 m ± 34.7 SD; p = 0.004). GPS accuracy in public transportation was 10.3 m ± 10.05 SD with a significant (p = 0.007) correlation between precision and phone brand. GPS resolution outdoors was 10.4 m ± 4.2 SD. Conclusion In our study several limitations of the DCT together with the impairment of GPS accuracy in urban settings impede the solely use of a DCT app. It could be feasible as a supplement to traditional manual contact tracing. DKRS, DRKS00029327 . Registered 20 June 2020 - Retrospectively registered

Direct and Indirect Pathways of Convected Water Masses and Their impacts on the Overturning Dynamics of the Labrador Sea

The dense waters formed by wintertime convection in the Labrador Sea play a key role in setting the properties of the deep Atlantic Ocean. To understand how variability in their production might affect the Atlantic Meridional Overturning Circulation (AMOC) variability, it is essential to determine pathways and associated timescales of their export. In this study, we analyze the trajectories of Argo floats and of Lagrangian particles launched at 53°N in the boundary current and traced backward in time in a high‐resolution model, to identify and quantify the importance of upstream pathways. We find that 85% of the transport carried by the particles at 53°N originates from Cape Farewell, and it is split between a direct route that follows the boundary current and an indirect route involving boundary‐interior exchanges. Although both routes contribute roughly equally to the maximum overturning, the indirect route governs its signal in denser layers. This indirect route has two branches: part of the convected water is exported rapidly on the Labrador side of the basin and part follows a longer route toward Greenland and is then carried with the boundary current. Export timescales of these two branches typically differ by 2.5 years. This study thus shows that boundary‐interior exchanges are important for the pathways and the properties of water masses arriving at 53°N. It reveals a complex three‐dimensional view of the convected water export, with implications for the arrival time of signals of variability therein at 53°N and thus for our understanding of the AMOC.S. Georgiou, S. L. Ypma, and J. ‐M. Sayol were supported by the Netherlands Organisation for Scientific Research (NWO) via VIDI grant 864.13.011 awarded to C. A. Katsman. N. Brüggemann was funded by the Collaborative Research Centre, TRR 181 “Energy Transfer in Atmosphere and Ocean” funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation, Germany) – Projektnummer 274762653. P. Spence is supported by ARC Future Fellowship FT190100413