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Wissen über Digitalisierung, Automatisierung und über „smarte“ Technologien sind Schlüssel für einen stabilen und nachhaltigen Erfolg von Klein- und Mittelunternehmen in der Region Salzburg. Die Fachhochschule Salzburg beantragte aus diesem Grund die Initiative Salzburg Smart Factory Bootcamp. Moderne und mobile Industrierobotik, kommunikative Software-Architekturen und OT-Sicherheit bilden die Basis für die Umsetzung aktueller Smart-Factory-Technologien und deren Potentiale in Unternehmen. Ziel des Bootcamps ist die gezielte Weiterqualifizierung mit modernsten Smart-Factory-Technologien von Mitarbeiterinnen und Mitarbeitern der beteiligten Unternehmen. Zusätzlich kann langfristig, auch über die beantragte Projektlaufzeit hinaus, die Zusammenarbeit zwischen Hochschule und Salzburger Unternehmen etabliert und weitergeführt werden.

In clinical routine, ophthalmologists frequently analyze the shape and size of the foveal avascular zone (FAZ) to detect and monitor retinal diseases. In order to extract those parameters, the contours of the FAZ need to be segmented, which is normally achieved by analyzing the retinal vasculature (RV) around the macula in fluorescein angiograms (FA). Computer-aided segmentation methods based on deep learning (DL) can automate this task. However, current approaches for segmenting the FAZ are often tailored to a specific dataset or require manual initialization. Furthermore, they do not take the variability and challenges of clinical FA into account, which are often of low quality and difficult to analyze. In this paper we propose a DL-based framework to automatically segment the FAZ in challenging FA scans from clinical routine. Our approach mimics the workflow of retinal experts by using additional RV labels as a guidance during training. Hence, our model is able to produce RV segmentations simultaneously. We minimize the annotation work by using a multi-modal approach that leverages already available public datasets of color fundus pictures (CFPs) and their respective manual RV labels. Our experimental evaluation on two datasets with FA from 1) clinical routine and 2) large multicenter clinical trials shows that the addition of weak RV labels as a guidance during training improves the FAZ segmentation significantly with respect to using only manual FAZ annotations.

The free jets of an axial and a centrifugal fan have been scanned by a specialized particle image velocimetry (PIV) set-up, which allows for volumetric scans of the time-averaged velocity field. Both of these fans have similar dimensions of approximately 70 mm x 70 mm x 25 mm. A classic PIV set-up was combined with a precise linear stage to move the fans through the laser fan beam in small steps, creating a dense array of measurement planes. Two components of the time-averaged velocity field are captured by the first 2.5D scan. Another scan, with the fan rotated by 90° about its outlet surface normal, captures the missing third velocity component. This article describes the details of the measurement set-up, and mentions measures concerning seeding, reflections, and calibration. In the signal processing stage, two independent sets of gathered image data have to be processed, producing two sets of velocity image frames. These are subsequently combined using gridded interpolation in order to obtain a 3D velocity field. Specifically devised software tools allow for a CFD-like analysis and visualization of the flow field. Typical parameters of the generated jets, like the spreading and rotation rates, are calculated from the measurement data and details of the outlet flow fields are investigated. The interpolated data are also used to analyze the influence of an assumed coarser measurement grid resolution on the results for the obtained outlet flow fields.

Purpose Cardiovascular disease and foremost coronary heart disease (CHD) are the worldwide leading causes of death. The aim of this study was to use non-invasive, multimodel retinal imaging to define microvascular features in patients with and without coronary angiography (CA)-confirmed CHD. Methods In this prospective, cross-sectional pilot study we included adult patients who presented to a tertiary referral center for elective CA due to suspected CHD. All patients underwent widefield fundus photography for retinopathy grading. Optical coherence tomography angiography was used to measure vessel density (VD) of the individual capillary plexuses in 6 × 6-mm macular volume scans. Adaptive optics imaging was performed to assess the first-order arteriolar lumen diameter (LD), total diameter (TD), wall-to-lumen ratio (WLR), and wall cross-section area, as well as to qualitatively describe vessel morphology. Results Of the included 45 patients (13 females; 65 ± 10 years old), 27 were confirmed with CHD in elective CA. The most prevalent retinal vascular pathologies were arteriovenous nickings, focal arterial narrowings, and microaneurysms. VD in the superficial capillary plexus, deep capillary plexus, and choriocapillaris was lower in CHD patients, although the odds ratios were not significantly different from 1 (P = 0.06-0.92). Median arterial LD, TD, and WLR values were 98.3 µm (interquartile range [IQR] = 13.0), 122.9 µm (IQR = 17.6), and 0.26 µm (IQR = 0.07), respectively, with a trend toward a higher WLR in CHD patients. Conclusions In a cardiovascular risk population, high-resolution quantitative and qualitative microvascular phenotyping in the retina may provide valuable subclinical indicators for coronary artery impairment, although larger clinical trials are needed. Translational relevance Subclinical retinal microvascular changes may serve as non-invasive, cost-effective biomarkers for risk stratification of patients with CHD.

Tantalum joined the list of 43 critical raw materials (CRM) within the latest report of the European Commission, published in 2017. Global Ta and Nb ore production, publicly known as Coltan, is dominated by D.R. Congo and Rwanda accounting for a combined share of at least 60%. Recycling constitutes an evolving chance for European countries to lower their complete reliance on importation. Consequently, tin slags as well as process residues like dusts or sludges are processed by pyrometallurgical treatment and hence offer great economic potential due to the content of valuable Ta2O5. Flowability tests with various atmospheres are performed to evaluate the similarity of industrial and synthetic slags. These experiments, thermodynamic FactSage simulations plus slag viscosity calculations provide a solid foundation for follow up high-temperature furnace rheometer trials which deepen fundamental knowledge about such melts and improve existing process steps.

This article presents a detailed investigation of the three-dimensional flow field produced by a small centrifugal fan used for cooling of electronic components, for instance, in the automotive industry. A particle image velocimetry (PIV) system captured numerous cross sections of the fan jet for analysis of velocity distribution and jet development. General parameters, such as the spreading rate, and flow specifics, such as the full width at half maximum contours in planes parallel to the fan outlet and the jet's rotation rate, were thus evaluated. In addition, constant temperature anemometry enabled a thorough investigation of the flow field at the fan's outflow port. Hot-wire measurements complement the PIV results by providing the power spectral density of the turbulent kinetic energy at several locations. Our results demonstrate that the cross-flow profile at the fan outlet consists of two counter-rotating vortices. This leads to a jet with a nearly elliptical, rotating cross section, which does not propagate in a direction perpendicular to the outlet plane. Several aspects of these distinctive flow features are evaluated and presented to provide both fluid mechanics and heat transfer engineers with (i) data on the air jet produced by a small centrifugal fan and (ii) reference data for computational fluid dynamics simulations. Despite complex flow development in the near field of the jet and the nonaxisymmetric jet contour in the intermediate field, our results are in good agreement with published data on axisymmetric jets in terms of spreading rate and the development of turbulence spectra observed in the intermediate field.

The production of synthetic tantalum concentrate (SynCon) from process residues, sludges or tin slags generates huge amounts of high melting slag, mostly comprising of Al2O3, CaO and SiO2. The metal/slag separation is a major criterion in the multi-stage pyrometallurgical procedure to ensure product quality and yield, wherefore the flow properties of respective slags depict essential preconditions. Hot stage microscope tests are performed to investigate the melting behaviour of synthetic SynCon slags under process near conditions (temperature range of 1000–1600 °C and reducing as well as inert atmosphere by usage of CO/CO2 and Ar gas). Sample analyses via REM/EDX and measured flow temperatures are compared to thermodynamic calculations conducted with FactSage 7.1 to enhance process control and to obtain first conceptions on the melting range and the slag viscosity, which are influenced by slag composition and temperature.

The ocean and sea ice in both polar regions are important reservoirs of freshwater within the climate system. While the response of these reservoirs to future climate change has been studied intensively, the sensitivity of the polar freshwater balance to natural forcing variations during preindustrial times has received less attention. Using an ensemble of transient simulations from 1500 to 2100 AD we put present-day and future states of the polar freshwater balance in the context of low frequency variability of the past five centuries. This is done by focusing on different multi-decadal periods of characteristic external forcing. In the Arctic, freshwater is shifted from the ocean to sea ice during the Maunder Minimum while the total amount of freshwater within the Arctic domain remains unchanged. In contrast, the subsequent Dalton Minimum does not leave an imprint on the slow-reacting reservoirs of the ocean and sea ice, but triggers a drop in the import of freshwater through the atmosphere. During the twentieth and twenty-first century the build-up of freshwater in the Arctic Ocean leads to a strengthening of the liquid export. The Arctic freshwater balance is shifted towards being a large source of freshwater to the North Atlantic ocean. The Antarctic freshwater cycle, on the other hand, appears to be insensitive to preindustrial variations in external forcing. In line with the rising temperature during the industrial era the freshwater budget becomes increasingly unbalanced and strengthens the high latitude’s Southern Ocean as a source of liquid freshwater to lower latitude oceans.

A broad spectrum of tantalum containing input materials can be processed for the production of synthetic tantalum concentrate (“SynCon”). The use of these low grade substances offers a secure alternative to mining of coltan in Central Africa. SynCon is produced in a multi-stage pyrometallurgical process, wherefore the melting behaviour of slags presents an important factor especially regarding the energy consumption and its optimisation. The characteristics of a slag comprising mostly Al2O3, CaO, SiO2 and MgO are influenced by the amount of other oxidic constituents which enfolds the main focus of this study. A hot stage microscope serves for the investigation of the slag behaviour in a temperature range from 1000 to 1600 °C under reducing atmosphere (CO/CO2 gas). The experimental results are compared with thermodynamic calculations (FactSage) to get a better understanding of the process.

Computing numerical approximations of the Huygens-Fresnel principle in three dimensions is demanding in terms of time and hardware, but thanks to massive parallelization in GPGPU-enabled graphics cards these computations can be sped up considerably. Our newly developed software framework is capable of simulating many wave propagation-related problems. Although it was initially intended to generate laser speckle images for various real physical setups used to measure the surface roughness of sheet metal and/or the oil film thickness upon it, it turned out to also be suitable for larger setups and apertures. This paper gives a short overview of the underlying physical and mathematical concepts and elaborates on the strengths and weaknesses of the numerics. We describe the theoretical background of rough wetting and the core parts of the software. Further, we present several test cases using apertures and their known Fraunhofer diffraction patterns and objective speckle patterns generated for rough surfaces.

Zusammenfassung Magnetfeldmessung für wenig Geld findet heute in jedem Smartphone statt. Dieser Artikel widmet sich dem wissenschaftlicheren Einsatz handelsüblicher Kompass-ICs. So können diese Bausteine z. B. in der zerstörungsfreien Werkstoffprüfung oder bei Strommessungen verlässliche Messdaten liefern, auch wenn die anschließende Interpretation dieser Datenflut neue Herausforderungen mit sich bringt. Konkret wird im folgenden Text die 2D Stromverteilung in einer Leiterbahn betrachtet. Auch wenn die Problemstellung simpel klingen mag, die Lösung des inversen Problems - des Findens der Stromdichten hinter den Messwerten - stellt sich als komplex heraus.

Using a highly resolved atmospheric general circulation model the impact of different glacial boundary conditions on precipitation and atmospheric dynamics in the North Atlantic region is investigated. Seven 30-yr time slice experiments of the Last Glacial Maximum (21 ka ago) and of a less pronounced glacial state – the Middle Weichselian (65 ka ago) – are compared to analyse the sensitivity to changes in the ice sheet distribution, in the radiative forcing, and in the prescribed time-varying lower boundary conditions, which are taken from a lower-resolved but fully-coupled atmosphere-ocean general circulation model. The strongest differences are found for simulations with different heights of the Laurentide ice sheet. A large altitude of this ice sheet leads to a southward displacement of the jet stream and the storm track in the North Atlantic region. These changes in the atmospheric dynamics generate a band of increased precipitation in the mid-latitudes across the Atlantic to southern Europe in winter, while the precipitation pattern in summer is only marginally affected. The impact of the radiative forcing differences between the two glacial periods and of the prescribed time-varying lower boundary conditions – evaluated using two simulations of the Last Glacial Maximum with a global mean temperature difference of 1.1 °C – are of second order compared to the one of the Laurentide ice sheet. They affect the atmospheric dynamics and precipitation in a similar but less pronounced manner as the topographic changes.

Objective To systematically review the survival rate and incidence of complications of furcation-involved multirooted teeth following periodontal therapy after at least 5 years. Material and methods Electronic and manual searches were performed up to and including January 2008. Publication selection, data extraction and validity assessment were performed independently by three reviewers. Results Twenty-two publications met the inclusion criteria. Because of the heterogeneity of the data, a meta-analysis could not be performed. The survival rate of molars treated non-surgically was >90% after 5-9 years. The corresponding values for the different surgical procedures were: Surgical therapy: 43.1% to 96%, observation period: 5-53 years. Tunnelling procedures: 42.9% to 92.9%, observation period: 5-8 years. Surgical resective procedures including amputation(s) and hemisections: 62% to 100%, observation period: 5-13 years. Guided tissue regeneration (GTR): 83.3% to 100%, observation period: 5-12 years. The most frequent complications included caries in the furcation area after tunnelling procedures and root fractures after root-resective procedures. Conclusions Good long-term survival rates (up to 100%) of multirooted teeth with furcation involvement were obtained following various therapeutic approaches. Initial furcation involvement (Degree I) could be successfully managed by non-surgical mechanical debridement. Vertical root fractures and endodontic failures were the most frequent complications observed following resective procedures.

Aim: The aim of the present study was to investigate the long-term results of periodontal supportive therapy in HIV-seropositive and HIV-seronegative patients. Material and methods: Baseline examination of 18 HIV-seropositive patients (14 males and four females, median age of 29.7 years) revealed the following periodontal diagnoses: eight patients with linear gingival erythema, four patients with necrotizing periodontitis, five patients with conventional gingivitis and one patient with chronic periodontitis. In the HIV-seronegative group, out of 16 patients (12 males and four females, median age 35.5 years), one patient presented with conventional gingivitis and 15 patients with chronic periodontitis. Periodontal therapy and maintenance care consisted of supra- and subgingival removal of plaque and calculus and instruction in oral hygiene. Based on the individual patient's needs, the mechanical therapy was repeated. Results: In the test group, the mean maintenance period was 22.7 ± 9.4 months (range 11.0–37.4) and in the control group, 48.9 ± 32.0 months (range 9.3–110.8). In the test group, the mean PlI (1.1 ± 0.8) remained at the same level (1.1 ± 0.5; p = 0.73, Wilcoxon sign rank test, p

The purpose of the present study was to investigate the effect of a single episode of scaling and root planing on clinical periodontal parameters and on the subgingival microflora in human immunodeficiency virus (HIV)-positive and HIV-negative subjects. 13 subjects participated and were clinically scored at days -7, 7, 30 and 90. 7 subjects were infected with HIV and presented an HIV-associated gingivitis. 6 subjects were HIV-negative with at least 12 teeth affected by conventional gingivitis. No significant differences were seen between both groups regarding the presence of P. gingivalis, P. intermedia and A. actinomycetemcomitans. The mean plaque index (PlI) was 1.79 in the HIV-negative and 1.29 in the HIV-positive group. The mean gingival index (GI) was higher in the HIV-positive group (HIV-positive: 1.55; HIV-negative: 1.47). Whereas, the PlI decreased significantly in the HIV-negative group during the course of the study, no change was observed in the HIV-positive group. GI as well as bleeding upon sampling decreased significantly in both patient groups during the same period. The bacterial counts decreased from day -7 to day 7 and generally remained on a lower level until day 90. Small differences were seen in the microbiological flora of the HIV-positive and the HIV-negative subjects following mechanical treatment.

[1] Winter circulation types under preindustrial and glacial conditions are investigated and used to quantify their impact on precipitation. The analysis is based on daily mean sea level pressure fields of a highly resolved atmospheric general circulation model and focuses on the North Atlantic and European region. We find that glacial circulation types are dominated by patterns with an east-west pressure gradient, which clearly differs from the predominantly zonal patterns for the recent past. This is also evident in the frequency of occurrence of circulation types when projecting preindustrial circulation types onto the glacial simulations. The elevation of the Laurentide ice sheet is identified as a major cause for these differences. In areas of strong precipitation signals in glacial times, the changes in the frequencies of occurrence of the circulation types explain up to 60% of the total difference between preindustrial and glacial simulations.

The variability of the Atlantic meridional overturing circulation (AMOC) strength is investigated in control experiments and in transient simulations of up to the last millennium using the low-resolution Community Climate System Model version 3. In the transient simulations the AMOC exhibits enhanced low-frequency variability that is mainly caused by infrequent transitions between two semi-stable circulation states which amount to a 10 percent change of the maximum overturning. One transition is also found in a control experiment, but the time-varying external forcing significantly increases the probability of the occurrence of such events though not having a direct, linear impact on the AMOC. The transition from a high to a low AMOC state starts with a reduction of the convection in the Labrador and Irminger Seas and goes along with a changed barotropic circulation of both gyres in the North Atlantic and a gradual strengthening of the convection in the Greenland-Iceland-Norwegian (GIN) Seas. In contrast, the transition from a weak to a strong overturning is induced by decreased mixing in the GIN Seas. As a consequence of the transition, regional sea surface temperature (SST) anomalies are found in the midlatitude North Atlantic and in the convection regions with an amplitude of up to 3 K. The atmospheric response to the SST forcing associated with the transition indicates a significant impact on the Scandinavian surface air temperature (SAT) in the order of 1 K. Thus, the changes of the ocean circulation make a major contribution to the Scandinavian SAT variability in the last millennium.

[1] Transient climate simulations are performed covering the period from 1630 to 2000. A vertically extended version of a coupled atmosphere-ocean general circulation model is used, including a detailed representation of the stratosphere. One simulation is driven by changes in total solar irradiance due to solar activity as well as volcanic eruptions and changes in greenhouse gas (GHG) concentrations. A second simulation additionally includes changes in short-wave heating due to prescribed photochemical changes in ozone. The simulations are compared with reconstructions and other simulations employing less resolved stratosphere. The inclusion of the higher resolved stratosphere plays only a moderate role for the simulated climate variability on the hemispheric scale. Larger implications are found for regional scales. Both simulations reveal a shift of the North Atlantic Oscillation toward a more positive phase from the Maunder Minimum to present day, mainly attributed to anthropogenic increase in concentration of well-mixed GHG. Increase in GHG is related to a more disturbed stratospheric polar vortex resulting in an only moderate strengthening of tropospheric westerlies over Europe compared with the tropospheric version of the model. On multidecadal to centennial time scales the stratospheric solar forcing substantially contributes to the climate change signal in the stratosphere, and there is clear evidence for an impact on the tropospheric circulation.

Image processing was used to efficiently calibrate a measurement set-up composed of multiple translation and rotation stages, and a sensing element fixed to a cantilever. Using the dimensions of individual devices to estimate the sensor position proved tedious: positioning and alignment errors between components accumulate and some physical dimensions are unknown or hard to measure. Defining a coordinate mapping via image processing seemed a convenient alternative and indeed typically yielded a measurement accuracy of less than 220 µm pixel width.The measurement rig was used to gather the magnetic field data of circular paths in a plane around electric conductors with a variety of cross-sections. To be of use in subsequent analysis steps, measurements had to be mapped by the calibration above onto both a cylinder and a Cartesian coordinate system. Additional error sources not accessible to visual inspection were identified when a calibration rod was measured. Correction of these errors completed the data preparation. As a proof of the concept, the centroid location and the integral current—two basic parameters of the current density which caused the magnetic field readings—were computed.