Ein flexibles, heterogenes Bildverarbeitungs-Framework für weltraumbasierte, rekonfigurierbare Datenverarbeitungsmodule

Scientific instruments as payload of current space missions are often equipped with high-resolution sensors. Thereby, especially camera-based instruments produce a vast amount of data. To obtain the desired scientific information, this data usually is processed on ground. Due to the high distance of missions within the solar system, the data rate for downlink to the ground station is strictly limited. The volume of scientific relevant data is usually less compared to the obtained raw data. Therefore, processing already has to be carried out on-board the spacecraft. An example of such an instrument is the Polarimetric and Helioseismic Imager (PHI) on-board Solar Orbiter. For acquisition, storage and processing of images, the instrument is equipped with a Data Processing Module (DPM). It makes use of heterogeneous computing based on a dedicated LEON3 processor in combination with two reconfigurable Xilinx Virtex-4 Field-Programmable Gate Arrays (FPGAs). The thesis will provide an overview of the available space-grade processing components (processors and FPGAs) which fulfill the requirements of deepspace missions. It also presents existing processing platforms which are based upon a heterogeneous system combining processors and FPGAs. This also includes the DPM of the PHI instrument, whose architecture will be introduced in detail. As core contribution of this thesis, a framework will be presented which enables high-performance image processing on such hardware-based systems while retaining software-like flexibility. This framework mainly consists of a variety of modules for hardware acceleration which are integrated seamlessly into the data flow of the on-board software. Supplementary, it makes extensive use of the dynamic in-flight reconfigurability of the used Virtex-4 FPGAs. The flexibility of the presented framework is proven by means of multiple examples from within the image processing of the PHI instrument. The framework is analyzed with respect to processing performance as well as power consumption.Wissenschaftliche Instrumente auf aktuellen Raumfahrtmissionen sind oft mit hochauflösenden Sensoren ausgestattet. Insbesondere kamerabasierte Instrumente produzieren dabei eine große Menge an Daten. Diese werden üblicherweise nach dem Empfang auf der Erde weiterverarbeitet, um daraus wissenschaftlich relevante Informationen zu gewinnen. Aufgrund der großen Entfernung von Missionen innerhalb unseres Sonnensystems ist die Datenrate zur Übertragung an die Bodenstation oft sehr begrenzt. Das Volumen der wissenschaftlich relevanten Daten ist meist deutlich kleiner als die aufgenommenen Rohdaten. Daher ist es vorteilhaft, diese bereits an Board der Sonde zu verarbeiten. Ein Beispiel für solch ein Instrument ist der Polarimetric and Helioseismic Imager (PHI) an Bord von Solar Orbiter. Um die Daten aufzunehmen, zu speichern und zu verarbeiten, ist das Instrument mit einem Data Processing Module (DPM) ausgestattet. Dieses nutzt ein heterogenes Rechnersystem aus einem dedizierten LEON3 Prozessor, zusammen mit zwei rekonfigurierbaren Xilinx Virtex-4 Field-Programmable Gate Arrays (FPGAs). Die folgende Arbeit gibt einen Überblick über verfügbare Komponenten zur Datenverarbeitung (Prozessoren und FPGAs), die den Anforderungen von Raumfahrtmissionen gerecht werden, und stellt einige existierende Plattformen vor, die auf einem heterogenen System aus Prozessor und FPGA basieren. Hierzu gehört auch das Data Processing Module des PHI Instrumentes, dessen Architektur im Verlauf dieser Arbeit beschrieben wird. Als Kernelement der Dissertation wird ein Framework vorgestellt, das sowohl eine performante, als auch eine flexible Bilddatenverarbeitung auf einem solchen System ermöglicht. Dieses Framework besteht aus verschiedenen Modulen zur Hardwarebeschleunigung und bindet diese nahtlos in den Datenfluss der On-Board Software ein. Dabei wird außerdem die Möglichkeit genutzt, die eingesetzten Virtex-4 FPGAs dynamisch zur Laufzeit zu rekonfigurieren. Die Flexibilität des vorgestellten Frameworks wird anhand mehrerer Fallbeispiele aus der Bildverarbeitung von PHI dargestellt. Das Framework wird bezüglich der Verarbeitungsgeschwindigkeit und Energieeffizienz analysiert

N,N'-dimethylperylene-3,4,9,10-bis(dicarboximide) on alkali halide(001) surfaces

The growth of N,N'-dimethylperylene-3,4,9,10-bis(dicarboximide) (DiMe-PTCDI) on KBr(001) and NaCl(001) surfaces has been studied. Experimental results have been achieved using frequency modulation atomic force microscopy at room temperature under ultra-high vacuum conditions. On both substrates, DiMe-PTCDI forms molecular wires with a width of 10 nm, typically, and a length of up to 600 nm at low coverages. All wires grow along the [110] direction (or [1$\bar{1}$0] direction, respectively) of the alkali halide (001) substrates. There is no wetting layer of molecules: Atomic resolution of the substrates can be achieved between the wires. The wires are mobile on KBr surface but substantially more stable on NaCl. A p(2 x 2) superstructure in brickwall arrangement on the ionic crystal surfaces is proposed based on electrostatic considerations. Calculations and Monte-Carlo simulations using empirical potentials reveal possible growth mechanisms for molecules within the first layer for both substrates, also showing a significantly higher binding energy for NaCl(001). For KBr, the p(2 x 2) superstructure is confirmed by the simulations, for NaCl, a less dense, incommensurate superstructure is predicted.Comment: 5 pages, 5 figure

Tailored nano-antennas for directional Raman studies of individual carbon nanotubes

We exploit the near field enhancement of nano-antennas to investigate the Raman spectra of otherwise not optically detectable carbon nanotubes (CNTs). We demonstrate that a top-down fabrication approach is particularly promising when applied to CNTs, owing to the sharp dependence of the scattered intensity on the angle between incident light polarization and CNT axis. In contrast to tip enhancement techniques, our method enables us to control the light polarization in the sample plane, locally amplifying and rotating the incident field and hence optimizing the Raman signal. Such promising features are confirmed by numerical simulations presented here. The relative ease of fabrication and alignment makes this technique suitable for the realization of integrated devices that combine scanning probe, optical, and transport characterization

That Girl of Mine

[Verse 1]Let me take you back once more to the good old days of yore. I can see my little sweet heart, the girl whom I adore. All my love I’m goin’ to save for the only one I crave; She won my heart right from the start and now it won’t behave. [Chorus] That girl of mine, oh how I love her, That girl of mine I’m dreaming of her Tho’ she’s many miles away, I’m with her ev’ry day In memo’ry and love so fond and true. That girl of mine, oh how I miss her And how my heart for her does pine. I’ve been a good old rover, but I’ll turn the world right over, For that girl of mine. That girl of mine. [Verse 2] I’ve got ev’ry precious note that my little sweetheart wrote. When we floated down the river on Dads old fishing boat. Though the years have sped away I write to her most ev’ry day, And very soon a wedding tune you’ll hear the organ play. [Chorus

The prognostic value of DLCO and pulmonary blood flow in patients with pulmonary hypertension

Background Cardiac output is a prognostic marker in patients with pulmonary hypertension. Pulmonary blood flow as a surrogate for cardiac output can be measured non-invasively by inert gas rebreathing. We hypothesized that pulmonary blood flow can predict outcome in patients with pulmonary hypertension. Methods From January 2009 to January 2012, we measured pulmonary blood flow by inert gas rebreathing in outpatients with pulmonary hypertension. Patients with pulmonary hypertension confirmed by right heart catheterization and a valid inert gas rebreathing maneuver were followed until January 2016. The investigated outcome was all-cause mortality. Results We included 259 patients (mean age 65 +/- 13 years, 53% female) with pulmonary hypertension and classified into groups 1 (n = 103), 2 (n = 26), 3 (n = 80), and 4 (n = 50) according to the current pulmonary hypertension classification system. The median time between pulmonary hypertension diagnosis and inert gas rebreathing was 9 (IQR 0; 36) months. During a median follow-up time of 51 (IQR 20; 68) months, 109 patients (42%) died. Parameters significantly associated with survival (in order of decreasing statistical strength) were diffusion capacity of the lung for carbon monoxide (DLCO), 6-minute walk distance (6-MWD), age, NTpro-BNP, WHO functional class, group 3 pulmonary hypertension, and tricuspid annular plane systolic excursion (TAPSE), while baseline hemodynamics and pulmonary blood flow were not. In multivariable Cox regression analysis, DLCO, age, 6-MWD, and TAPSE remained significant and independent predictors of the outcome. DLCO as the strongest parameter also significantly predicted survival in aetiological subgroups except for group 4. Conclusions DLCO is a strong and independent predictor for survival in patients with pulmonary hypertension of different aetiologies, while pulmonary blood flow measured by inert gas rebreathing is not

Privacy at Risk: Exploiting Similarities in Health Data for Identity Inference

Smartwatches enable the efficient collection of health data that can be used for research and comprehensive analysis to improve the health of individuals. In addition to the analysis capabilities, ensuring privacy when handling health data is a critical concern as the collection and analysis of such data become pervasive. Since health data contains sensitive information, it should be handled with responsibility and is therefore often treated anonymously. However, also the data itself can be exploited to reveal information and break anonymity. We propose a novel similarity-based re-identification attack on time-series health data and thereby unveil a significant vulnerability. Despite privacy measures that remove identifying information, our attack demonstrates that a brief amount of various sensor data from a target individual is adequate to possibly identify them within a database of other samples, solely based on sensor-level similarities. In our example scenario, where data owners leverage health data from smartwatches, findings show that we are able to correctly link the target data in two out of three cases. User privacy is thus already inherently threatened by the data itself and even when removing personal information

Effect of a simple intervention on hand hygiene related diseases in preschools in South Africa: research protocol for an intervention study

Abstract : Introduction Hand hygiene (HH) related illnesses such as diarrhoea and respiratory diseases, contribute to the burden of disease and are included in the top five causes of mortality in children under 5 years in South Africa. Children attending preschools are more susceptible to these infections due to the higher number of children in preschools. HH interventions have shown to reduce HH-related diseases by improving HH practices. In South Africa, there are no documented HH interventions or studies in children under 5 years. The purpose of the study is to determine whether an HH intervention can reduce HH-related diseases among 4–5-year- old preschool children and to improve HH practices in these children, their caregivers and their parents..

Discrete-time Analysis of Multicomponent GI/GI/1 Queueing Networks

In this work, we provide initial insights regarding the error introducedinto multicomponent queueing systems by assuming the departure processes of arbitraryGI/GI/1-oo queues to be renewal processes. To this end, we compute the sojourntime distribution as well as departure distributions of a linear chain of queueingcomponents and compare the results to a simulation of the same system. By applyingthe renewal approximation, potential autocorrelations of the departure processesare lost. We investigate the magnitude of this error regarding both the sojourn timeas well as interdeparture time distributions for a broad set of parameters. Althoughmore indepth studies are needed, our results show that both distributions can beclosely approximated, which allows the application of the model to asses the performanceof real world NFV function chains

Liquid Saturation and Gas-Liquid Distribution in Multiphase Monolithic Reactors

The Monolith Bed is One of the Promising Catalytic Reactors for a Number of Chemical Gas-Liquid-Solid Processes. in the Present Work, Liquid Saturations for Five Different Monoliths Have Been Investigated Experimentally in a Cold-Flow Unit with a Reactor Diameter of 5.0 Cm. the Influences of Gas and Liquid Flow Rates and of the Direction of Two-Phase Flow on Liquid Saturation Were Examined. the Results Indicate that the Direction of Flow Has No Significant Influence on Liquid Saturation for Proper Gas-Liquid Distribution. the Experimental Results Are in Good Agreement with Predictions of the Drift Flux Model using the Distribution Parameter Proposed by Ishii (ANL Report ANL-77-47, 1977) Along with the Assumption of Zero Drift Velocity. in Preliminary Experiments, Gamma-Ray Computed Tomography (CT) Has Been Successfully Applied to Measure Time-Averaged Liquid Distribution over the Monolith Cross-Section in a Selected Condition. the Employment of a Nozzle-Type Distributor Provides an Almost Uniform Liquid Distribution over the Monolith Substrate. It is Demonstrated that CT is a Viable Technique for Studying Two-Phase Flow in Laboratory-Scale Monolith Reactors. © 2005 Elsevier Ltd. All Rights Reserved