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Disentangling Embedding Spaces with Minimal Distributional Assumptions [article]

Tobias Leemann, Michael Kirchhof, Yao Rong, Enkelejda Kasneci, Gjergji Kasneci
2022 arXiv   pre-print
The authors thank the International Max Planck Research School for Intelligent Systems (IMPRS-IS) for supporting Michael Kirchhof.  ... 
arXiv:2206.13872v1 fatcat:hk667hlhrzcyjgrbk7y46v6jvy

pRSL: Interpretable Multi-label Stacking by Learning Probabilistic Rules [article]

Kirchhof Michael and Schmid Lena and Reining Christopher and ten Hompel Michael and Pauly Markus
2021 arXiv   pre-print
Michael Rapp, Eneldo Loza Mencía, Johannes Fürnkranz, Vu-Linh Nguyen, and Eyke Hüllermeier. Learning Gradi- ent Boosted Multi-label Classification Rules.  ...  Kirchhof conceived and implemented the idea and wrote the paper. L. Schmid conceived the idea and edited the paper. C. Reining advised on required conditions from a practical perspective. M. t.  ... 
arXiv:2105.13850v1 fatcat:aqrktgj3zrhvrgvy6m4kh56fuu

Integrated Low-Cost eHome Systems: Prozesse und Infrastrukturen

Michael Kirchhof
2007 Softwaretechnik-Trends  
dblp:journals/stt/Kirchhof07 fatcat:pyrhdhpeirb2tnz6fw2miolts4

Variant and Product Line Co-Evolution [chapter]

Jörg Christian Kirchhof, Michael Nieke, Ina Schaefer, David Schmalzing, Michael Schulze
2020 Model-Based Engineering of Collaborative Embedded Systems  
AbstractIndividual collaborative embedded systems (CESs) in a collaborative system group (CSG) are typically provided by different manufacturers. Variability in such systems is pivotal for deploying a CES in different CSGs and environments. Changing requirements may entail the evolution of a CES. Such changed requirements can be manifold: individual variants of a CES are updated to fix bugs, or the manufacturer changes the entire CES product line to provide new capabilities. Both types of
more » ... ion, the variant evolution and the product line evolution, may be performed in parallel. However, neither type of evolution should lead to diverging states of CES variants and the CES product line, otherwise both would be incompatible, it would not be possible to update the CES variants, and it would not be possible to reuse bug fixes of an individual variant for the entire product line. To avoid this divergence, we present an approach for co-evolving variants and product lines, thus ensuring their consistency.
doi:10.1007/978-3-030-62136-0_18 fatcat:4gv2ikngcrejndyr6vm4ycifme

A Non-isotropic Probabilistic Take on Proxy-based Deep Metric Learning [article]

Michael Kirchhof, Karsten Roth, Zeynep Akata, Enkelejda Kasneci
2022 arXiv   pre-print
Proxy-based Deep Metric Learning (DML) learns deep representations by embedding images close to their class representatives (proxies), commonly with respect to the angle between them. However, this disregards the embedding norm, which can carry additional beneficial context such as class- or image-intrinsic uncertainty. In addition, proxy-based DML struggles to learn class-internal structures. To address both issues at once, we introduce non-isotropic probabilistic proxy-based DML. We model
more » ... es as directional von Mises-Fisher (vMF) distributions on the hypersphere that can reflect image-intrinsic uncertainties. Further, we derive non-isotropic von Mises-Fisher (nivMF) distributions for class proxies to better represent complex class-specific variances. To measure the proxy-to-image distance between these models, we develop and investigate multiple distribution-to-point and distribution-to-distribution metrics. Each framework choice is motivated by a set of ablational studies, which showcase beneficial properties of our probabilistic approach to proxy-based DML, such as uncertainty-awareness, better-behaved gradients during training, and overall improved generalization performance. The latter is especially reflected in the competitive performance on the standard DML benchmarks, where our approach compares favorably, suggesting that existing proxy-based DML can significantly benefit from a more probabilistic treatment. Code is available at github.com/ExplainableML/Probabilistic_Deep_Metric_Learning.
arXiv:2207.03784v1 fatcat:upfhvi5p65bnxhu4hbamuki2ca

12 Jahre AFNET. Vom Forschungsnetzwerk zur Academic Research Organisation

Paulus Kirchhof, Andreas Goette, Michael Näbauer, Ulrich Schotten
2016 Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz  
Kirchhof Kompetenznetz Vorhofflimmern Mendelstraße 11, 48149 Münster, Deutschland info@kompetenznetz-vorhofflimmern.de p.kirchhof@bham.ac.uk Danksagung.  ...  Kirchhof, A. Goette, M. Näbauer und U. Schotten geben an, dass kein Interessenkonflikt besteht. Dieser Beitrag beinhaltet keine Studien an Menschen oder Tieren.  ... 
doi:10.1007/s00103-016-2323-x pmid:26979716 fatcat:idbs34wiuvdv3nt2t7qkjilujy

Postrepolarization Refractoriness Versus Conduction Slowing Caused by Class I Antiarrhythmic Drugs

Paulus F. Kirchhof, C. Larissa Fabritz, Michael R. Franz
1998 Circulation  
Background-Conduction block may be both antiarrhythmic and proarrhythmic. Drug-induced postrepolarization refractoriness (PRR) may prevent premature excitation and tachyarrhythmia induction. The effects of propafenone and procainamide on these parameters, and their antiarrhythmic or proarrhythmic consequences, were investigated. Methods and Results-In 11 isolated Langendorff-perfused rabbit hearts, monophasic action potentials (MAPs) were recorded simultaneously from six to seven different
more » ... and left ventricular sites, along with a volume-conducted ECG. All recordings were used to discern ventricular tachycardia (VT) or ventricular fibrillation (VF) induced by repetitive extrastimulation (S2-S5) or 10-second burst stimulation at 25 to 200 Hz at baseline and after addition of procainamide (20 mol/L) or propafenone (1 mol/L) to the perfusate. MAPs were analyzed for action potential duration at 90% repolarization (APD 90 ), conduction times (CT) between the pacing site and the other MAPs, and PRR (effective refractory periodϪAPD 90 ϭPRR) and related to the induction of VT or VF. During steady-state pacing, procainamide and propafenone prolonged APD 90 by 12% and 14%, respectively. Procainamide slowed mean CT by 40% during S2-S5 pacing, whereas propafenone slowed mean CT by up to 400% (PϽ0.001 versus baseline and procainamide). Wavelength was not changed significantly by procainamide but was shortened fourfold by propafenone at S5. Both drugs produced PRR, which was associated with a 70% decrease in VF inducibility with procainamide and elimination of VF with propafenone. Despite this protection from VF, monomorphic VT was induced with propafenone in 57% of burst stimulations. Conclusions-Drug-induced PRR protects against VF induction. Propafenone promotes slow monomorphic VT, probably by use-dependent conduction slowing and wavelength shortening. (Circulation. 1998;97:2567-2574.)
doi:10.1161/01.cir.97.25.2567 pmid:9657478 fatcat:6jz4f2kvx5ewtprswde3im7bhi

Automatic Evaluation of Landmarks for Image-Based Navigation Update

Stefan Lang, Michael Kirchhof
2009 EURASIP Journal on Advances in Signal Processing  
Michael Arens and Dr. Rolf Schäfer. Last but not least, the authors thank Marcus Hebel for processing the LiDAR data.  ... 
doi:10.1155/2009/467549 fatcat:dculeju7rfaslkfh4cbtjdt4de

Homogeneous temperature and precipitation series of Switzerland from 1864 to 2000

Michael Begert, Thomas Schlegel, Walter Kirchhofer
2005 International Journal of Climatology  
A set of 12 homogenized monthly mean temperature and precipitation series of Switzerland for the period 1864-2000 are introduced. The standardized homogenization procedure, which has been developed and implemented at MeteoSwiss during recent years, is briefly reviewed and the inhomogeneity types, causes, magnitudes, and timings are discussed. Finally, a trend analysis is performed on each temperature and precipitation series and on a mean temperature series of Switzerland. The results are
more » ... ed with findings of other studies that have examined long-term temperature and precipitation trends in Switzerland and neighbouring countries. The inhomogeneities of the Swiss temperature series are up to ±1.6°C and the precipitation adjustment factors vary between 0.5 and 1.6. Each of the 12 temperature series analysed contains several inhomogeneities that cause systematic biases in the adjustment curves. The slope of a mean temperature curve derived from the original data is underestimated by 0.4°C/100 years. All precipitation series except one contain inhomogeneities, but no systematic bias is observed. The trend analysis reveals an increase in the yearly temperature series ranging from 0.9°C/100 years to 1.1°C/100 years at stations north of the alpine main crest and ∼0.6°C/100 years at southern stations. Precipitation trends are observed at most sites north of the alpine main crest in winter and in some of the yearly series. The annual slopes vary between 7 and 10% and the winter slopes between 16 and 37%.
doi:10.1002/joc.1118 fatcat:gabmzph26jbthphs2rzadmwfgm

Dogs (Canis familiaris), but Not Chimpanzees (Pan troglodytes), Understand Imperative Pointing

Katharina C. Kirchhofer, Felizitas Zimmermann, Juliane Kaminski, Michael Tomasello, Brock Fenton
2012 PLoS ONE  
Chimpanzees routinely follow the gaze of humans to outside targets. However, in most studies using object choice they fail to use communicative gestures (e.g. pointing) to find hidden food. Chimpanzees' failure to do this may be due to several difficulties with this paradigm. They may, for example, misinterpret the gesture as referring to the opaque cup instead of the hidden food. Or perhaps they do not understand informative communicative intentions. In contrast, dogs seem to be skilful in
more » ... g human communicative cues in the context of finding food, but as of yet there is not much data showing whether they also use pointing in the context of finding non-food objects. Here we directly compare chimpanzees' (N = 20) and dogs' (N = 32) skills in using a communicative gesture directed at a visible object out of reach of the human but within reach of the subject. Pairs of objects were placed in view of and behind the subjects. The task was to retrieve the object the experimenter wanted. To indicate which one she desired, the experimenter pointed imperatively to it and directly rewarded the subject for handing over the correct one. While dogs performed well on this task, chimpanzees failed to identify the referent. Implications for great apes' and dogs' understanding of human communicative intentions are discussed.
doi:10.1371/journal.pone.0030913 pmid:22347411 pmcid:PMC3275610 fatcat:2kxgwops7jbmvkmb3igtcexvvq

Danshen (Salvia miltiorrhiza) on the Global Market: What Are the Implications for Products' Quality?

Ka Yui Kum, Rainer Kirchhof, Rainer Luick, Michael Heinrich
2021 Frontiers in Pharmacology  
Danshen (Radix et rhizoma Salviae miltiorrhizae; Salvia miltiorrhiza Bunge, Lamiaceae) is commonly used in Asia, including China, Japan, and Korea with markets in America and Europe growing substantially. It is included in multiple pharmacopeias and salvianolic acid B and tanshinone IIA are used as quality markers. However, on the markets, substitutes and different processing methods often are a concern. a concern regarding patients' safety and expected outcomes. Aims: This study aims at
more » ... anding the quality of Danshen-derived products on the market, and the relationship between the chemistry, biological activity and the processing and storage methods. Methods: For heavy metal analysis, inductively coupled plasma optical emission spectrometry was used. High performance thin-layer chromatography and proton nuclear magnetic resonance coupled with principal component analysis were used to understand the variation of metabolite composition. MTT assay and LPS induced NO production assay were used to evaluate the cytotoxicity effect and anti-inflammatory activity, respectively. Result and Discussion: Six out of sixty samples exceed the limits of cadmium according to the Chinese or United States Pharmacopoeia. Arsenic, lead and copper contents are all below pharmacopoeial thresholds. With more complex processing procedure, the risk of heavy metal contamination increases, especially with arsenic and cadmium. The metabolite compositions show a variability linked to processing and storage methods. Authenticated samples and Vietnamese primary samples contain higher salvianolic acid B, and their chemical compositions are more consistent compared to Chinese online store samples. Overall, a significant chemical variation can be observed in Danshen products directly linked to processing and storage method. In the MTT assay, fourteen samples show cytotoxicity while seven samples increase the proliferation of RAW264.7. In the LPS induced NO production of RAW 264.7, only seven samples show significant inhibitory effects. Conclusion: This is the first interdisciplinary investigation focusing on understanding the current market and the quality of Danshen. The quality of Danshen products on the high street are inferior to the authenticated samples. The results of the bioassays selected is not useful to differentiate the quality and composition according to the current definition in the pharmacopoeias. Overall, this approach highlights the tremendous variability of the products linked to processing and the need for more systematic and stringent quality assurance.
doi:10.3389/fphar.2021.621169 pmid:33981218 pmcid:PMC8107819 fatcat:ej63drnpyng47e23lxach73jyy

Process Support in eHome Systems: Empowering Providers to Handle a Future Mass Market

Ibrahim Armac, Michael Kirchhof
2006 International Conference on Advanced Information Systems Engineering  
This paper focuses on the sales and distribution phase in eHome systems. The huge market potential for affordable solutions leads to a multiplicity in terms of millions of installations in parallel. This situation can not be handled manually. So, tool support for the business process in this phase is crucial. We discuss the prerequisites of the intended tool support, starting with the overall eHome process which describes the complete life cycle of eHome services. Then, we will further analyze
more » ... he sales and distribution phase and formalize the encapsulated business process. This process specification is executed by an established workflow management system. Summarizing, we present a solution based on automated configuration and deployment techniques, which enables the efficient advertising, migration, and retirement of components in the particularly specific domain of eHome systems.
dblp:conf/caise/ArmacK06 fatcat:2iegc3wtrfewvoa67e2kajqnsa

Unraveling the Allosteric Mechanism of Serine Protease Inhibition by an Antibody

Rajkumar Ganesan, Charles Eigenbrot, Yan Wu, Wei-Ching Liang, Steven Shia, Michael T. Lipari, Daniel Kirchhofer
2009 Structure  
., 2008) , sodium for thrombin (Huntington, 2008; Wells and Di Cera, 1992) , cofactors such as tissue factor for coagulation factor VIIa (Eigenbrot and Kirchhofer, 2002) , and N-terminal peptide insertion  ...  Pro-HGF activation assays with active-site-titrated HGFA were carried out essentially as described elsewhere (Kirchhofer et al., 2003) using serial dilutions of antibody incubated with 1 nM HGFA and  ... 
doi:10.1016/j.str.2009.09.014 pmid:20004165 fatcat:hpw26g7x65chta4semb3llfada

Mutagenesis and Functional Studies with Succinate Dehydrogenase Inhibitors in the Wheat Pathogen Mycosphaerella graminicola

Gabriel Scalliet, Judith Bowler, Torsten Luksch, Lucy Kirchhofer-Allan, Diana Steinhauer, Keith Ward, Michael Niklaus, Andreas Verras, Michael Csukai, Antoine Daina, Raymonde Fonné-Pfister, Olivier Lespinet
2012 PLoS ONE  
Citation: Scalliet G, Bowler J, Luksch T, Kirchhofer-Allan L, Steinhauer D, et al. (2012) Mutagenesis and Functional Studies with Succinate Dehydrogenase Inhibitors in the Wheat Pathogen Mycosphaerella  ... 
doi:10.1371/journal.pone.0035429 pmid:22536383 pmcid:PMC3334918 fatcat:n24y6jdb7zcfxi3qqpb3rdke3i

Iterative processing of laser scanning data by full waveform analysis

Michael Kirchhof, Boris Jutzi, Uwe Stilla
2008 ISPRS journal of photogrammetry and remote sensing (Print)  
The latest developments in laser scanners allow capturing and digitizing of the full waveform of the backscattered pulse. The waveform can be analyzed for measurement features such as range, reflectance values and spreading of the pulse. These features are used to distinguish between locally planar surface elements and partly penetrable objects caused by partial occlusions. This presegmentation and the derived range values are used to automatically generate surface primitives in the form of
more » ... es. This allows refining each range value taking the surface geometry in a close neighborhood into account. To refine the modeling of the surface, partly occluded surface areas are extended by prediction of the expected range values. This prediction is further improved by considering the surface slope for the estimated received waveform. Then the point cloud associated with the surface is enhanced by additional range values that were missed in the first processing step due to weak signal response. This procedure is repeated several times until all useful range values are considered to estimate the surface.
doi:10.1016/j.isprsjprs.2007.08.006 fatcat:srbjuk5id5dw5ioecuk3fjozfm
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