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ARTIFACT: Architecture for Automated Generation of Distributed Information Extraction Pipelines (2022)
Sildatke, Michael ; Karwanni, Hendrik ; Kraft, Bodo ; Zündorf, Albert
Companies often have to extract information from PDF documents by hand since these documents only are human-readable. To gain business value, companies attempt to automate these processes by using the newest technologies from research. In the field of table analysis, e.g., several hundred approaches were introduced in 2019. The formats of those PDF documents vary enormously and may change over time. Due to that, different and high adjustable extraction strategies are necessary to process the documents automatically, while specific steps are recurring. Thus, we provide an architectural pattern that ensures the modularization of strategies through microservices composed into pipelines. Crucial factors for success are identifying the most suitable pipeline and the reliability of their result. Therefore, the automated quality determination of pipelines creates two fundamental benefits. First, the provided system automatically identifies the best strategy for each input document at runtim e. Second, the provided system automatically integrates new microservices into pipelines as soon as they increase overall quality. Hence, the pattern enables fast prototyping of the newest approaches from research while ensuring that they achieve the required quality to gain business value.
Gangkinematik beim Tragen eines Tisches mit einem robotischen Tragepartner (2022)
Schüngel, Verena ; Braunstein, Björn ; Göll, Fabian ; Reißer, Nadine ; Zimmermann, Uwe ; Albracht, Kirsten
Cervical spine and muscle adaptation after spaceflight and relationship to herniation risk: protocol from ‘Cervical in Space’ trial (2022)
Belavy, Daniel L. ; Armbrecht, Gabriele ; Albracht, Kirsten ; Brisby, Helena ; Falla, Deborah ; Scheuring, Richard ; Sovelius, Roope ; Wilke, Hans-Joachim ; Rennerfelt, Kajsa ; Martinez-Valdes, Eduardo ; Arvanitidis, Michail ; Goell, Fabian ; Braunstein, Björn ; Kaczorowski, Svenja ; Karner, Vera ; Kumar Arora, Nitin
Background Astronauts have a higher risk of cervical intervertebral disc herniation. Several mechanisms have been attributed as causative factors for this increased risk. However, most of the previous studies have examined potential causal factors for lumbar intervertebral disc herniation only. Hence, we aim to conduct a study to identify the various changes in the cervical spine that lead to an increased risk of cervical disc herniation after spaceflight. Methods A cohort study with astronauts will be conducted. The data collection will involve four main components: a) Magnetic resonance imaging (MRI); b) cervical 3D kinematics; c) an Integrated Protocol consisting of maximal and submaximal voluntary contractions of the neck muscles, endurance testing of the neck muscles, neck muscle fatigue testing and questionnaires; and d) dual energy X-ray absorptiometry (DXA) examination. Measurements will be conducted at several time points before and after astronauts visit the International Space Station. The main outcomes of interest are adaptations in the cervical discs, muscles and bones. Discussion Astronauts are at higher risk of cervical disc herniation, but contributing factors remain unclear. The results of this study will inform future preventive measures for astronauts and will also contribute to the understanding of intervertebral disc herniation risk in the cervical spine for people on Earth. In addition, we anticipate deeper insight into the aetiology of neck pain with this research project.
Beanspruchung der Halswirbelsäule bei Eurofighter-Piloten unter „high-Gz“ im Realflug (2022)
Lingscheid, René ; Göll, Fabian ; Nuesse, Roland ; Albracht, Kirsten ; Braunstein, Björn
Kampfpiloten sind in Abhängigkeit vom Luftfahrzeugmuster und ihrem jeweiligen fliegerischen Auftrag ­Beschleunigungen im Bereich des 5- bis 9-fachen der Erdbeschleunigung ausgesetzt. Das uneingeschränkte Bewegungsvermögen der Halswirbelsäule auch unter hoher G-Belastung ist essenziell für die visuelle Beobachtung des umgebenden Luftraums und somit für den Einsatzwert. Der Hals- und Nackenbereich gilt als vulnerable Region, da es kein protektives Entlastungs- oder Schutzsystem (z.B. Anti-G-Suite, Helm) für die HWS gibt.
FUSION: Feature-based Processing of Heterogeneous Documents for Automated Information Extraction (2022)
Sildatke, Michael ; Karwanni, Hendrik ; Kraft, Bodo ; Zündorf, Albert
Information Extraction (IE) processes are often business-critical, but very hard to automate due to a heterogeneous data basis. Specific document characteristics, also called features, influence the optimal way of processing. Architecture for Automated Generation of Distributed Information Extraction Pipelines (ARTIFACT) supports businesses in successively automating their IE processes by finding optimal IE pipelines. However, ARTIFACT treats each document the same way, and does not enable document-specific processing. Single solution strategies can perform extraordinarily well for documents with particular traits. While manual approvals are superfluous for these documents, ARTIFACT does not provide the opportunity for Fully Automatic Processing (FAP). Therefore, we introduce an enhanced pattern that integrates an extensible and domain-independent concept of feature detection based on microservices. Due to this, we create two fundamental benefits. First, the document-specific process ing increases the quality of automated generated IE pipelines. Second, the system enables FAP to eliminate superfluous approval efforts.
Optimal particles for highly sensitive biosensing application in mixed frequency excitation: Insights from a fundamental simulative approach (2022)
Engelmann, Ulrich M. ; Shalaby, Ahmed ; Krause, Hans-Joachim
Magnetic nanoparticles (MNP) are widely investigated for biomedical applications in diagnostics (e.g. imaging), therapeutics (e.g. hyperthermia) and general biosensing. For all these applications, the MNPs’ unique magnetic relaxation mechanism in an alternating magnetic field (AFM) is stimulated to induce desired effects. Whereas magnetic fluid hyperthermia (MFH) and magnetic particle imaging (MPI) are the most prominent examples for biomedical application, we investigate the relatively new biosensing application of frequency mixing magnetic detection (FMMD) from a fundamental perspective. Generally, we ask how specific MNP parameters (core size, magnetic anisotropy) influence the signal, specifically we predict the most effective MNP core size for signal generation. In FMMD, simultaneously two AFM are applied: a low-frequency magnetic driving field, driving MNP close to saturation, and a high-frequency excitation field that probes MNP susceptibility: . Resulting from the nonlinear magnetization of the MNP, harmonics of both individual incident frequencies as well as intermodulation products of these frequencies are generated. In this work, we present numerical Monte-Carlo(MC)-based simulations of the MNP relaxation process, solving the Landau-Lifshitz-Gilbert (LLG) equation to predict FMMD signals: As Figure 1 shows for the first four intermodulation signals , with , we can clearly see that larger core sizes generally increase the signal intensity. Same trend is predicted by a simple Langevin-function based thermal equilibrium model. Both predictions include a lognormal size distribution. The effect of core size distribution presumably dominates the effect of magnetic anisotropy. The findings are supported by comparison with experimental data and help to identify which MNP are best suited for magnetic biosensing applications using FMMD.
Resolving ambiguities in core size determination of magnetic nanoparticles from magnetic frequency mixing data (2022)
Pourshahidi, Ali Mohammad ; Engelmann, Ulrich M. ; Offenhäusser, Andreas ; Krause, Hans-Joachim
Frequency mixing magneticdetection(FMMD) has been widely utilized as a measurement technique in magnetic immunoassays. It can also be used for characterization[1]and distinction[2](also known as “colorization”) ofdifferent types of magnetic nanoparticlesaccording totheircore sizes.It is well known that the large particles contribute most of the FMMD signal. Typically, 90% of the signal stems from the largest 10% of the particles [1]. This leads to ambiguities in core size fitting since thecontribution of thesmall sized particles is almostundetectable among the strong responses from the large ones. In this work, we report on how this ambiguity can be overcome. Magnetic nanoparticle samples from Micromod (Rostock, Germany) were prepared in liquid and filterbound state. Their FMMD response at mixing frequencies f1 ± nf2 to magnetic excitation H(t)=H0+H1sin(2 f1t)+H2sin(2 f2t),with H1=1.3mT/μ0 at f1=40.5kHzandH2=16mT/μ0 at f2=63Hz,was measured as a function ofoffset field strength H0= (0,…,24) mT/μ0.The signal calculated fromLangevin model in thermodynamic equilibrium[1]with a lognormal core size distribution fL(dc,d0, ,A) = Aexp(–ln²(dc/d0)/(2 ²))/(dc (2 )1/2)was fitted to the experimental data. For each choice of median diameter d0, pairs of parameters ( ,A) are found which yield excellent fit results with R²>0.99.All the lognormal core size distributions shown in Figure (a) are compatible with the measurements because their large-size tails are almost equal. However, all distributions have different number of particles and different total iron content. We determined the samples’ total iron mass with inductively coupled plasma optical emission spectrometry(ICP-OES) and, out of all possible lognormal distributions, determined the one with the same amount of iron. With this additional externally measured parameter, we resolved the ambiguity in core size distribution and determined the parameters (d0, ,A).
Daily variations of corneal white-to-white diameter measured with different methods (2022)
Bandlitz, Stefan ; Nakhoul, Makram ; Kotliar, Konstantin
Purpose: A precise determination of the corneal diameter is essential for the diagnosis of various ocular diseases, cataract and refractive surgery as well as for the selection and fitting of contact lenses. The aim of this study was to investigate the agreement between two automatic and one manual method for corneal diameter determination and to evaluate possible diurnal variations in corneal diameter. Patients and Methods: Horizontal white-to-white corneal diameter of 20 volunteers was measured at three different fixed times of a day with three methods: Scheimpflug method (Pentacam HR, Oculus), placido based topography (Keratograph 5M, Oculus) and manual method using an image analysis software at a slitlamp (BQ900, Haag-Streit). Results: The two-factorial analysis of variance could not show a significant effect of the different instruments (p = 0.117), the different time points (p = 0.506) and the interaction between instrument and time point (p = 0.182). Very good repeatability (intraclass correlation coefficient ICC, quartile coefficient of dispersion QCD) was found for all three devices. However, manual slitlamp measurements showed a higher QCD than the automatic measurements with the Keratograph 5M and the Pentacam HR at all measurement times. Conclusion: The manual and automated methods used in the study to determine corneal diameter showed good agreement and repeatability. No significant diurnal variations of corneal diameter were observed during the period of time studied.
Analysis and computation of the transmission eigenvalues with a conductive boundary condition (2022)
Harris, Isaac ; Kleefeld, Andreas
We provide a new analytical and computational study of the transmission eigenvalues with a conductive boundary condition. These eigenvalues are derived from the scalar inverse scattering problem for an inhomogeneous material with a conductive boundary condition. The goal is to study how these eigenvalues depend on the material parameters in order to estimate the refractive index. The analytical questions we study are: deriving Faber–Krahn type lower bounds, the discreteness and limiting behavior of the transmission eigenvalues as the conductivity tends to infinity for a sign changing contrast. We also provide a numerical study of a new boundary integral equation for computing the eigenvalues. Lastly, using the limiting behavior we will numerically estimate the refractive index from the eigenvalues provided the conductivity is sufficiently large but unknown.
Towards Topological Analysis of Non-symmetric Tensor Fields via Complexification (2022)
Burgeth, Bernhard ; Kleefeld, Andreas ; Zhang, Eugene ; Zhang, Yue
Fields of asymmetric tensors play an important role in many applications such as medical imaging (diffusion tensor magnetic resonance imaging), physics, and civil engineering (for example Cauchy-Green-deformation tensor, strain tensor with local rotations, etc.). However, such asymmetric tensors are usually symmetrized and then further processed. Using this procedure results in a loss of information. A new method for the processing of asymmetric tensor fields is proposed restricting our attention to tensors of second-order given by a 2x2 array or matrix with real entries. This is achieved by a transformation resulting in Hermitian matrices that have an eigendecomposition similar to symmetric matrices. With this new idea numerical results for real-world data arising from a deformation of an object by external forces are given. It is shown that the asymmetric part indeed contains valuable information.
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