24 research outputs found
Don't Forget The Past: Recurrent Depth Estimation from Monocular Video
Autonomous cars need continuously updated depth information. Thus far, depth
is mostly estimated independently for a single frame at a time, even if the
method starts from video input. Our method produces a time series of depth
maps, which makes it an ideal candidate for online learning approaches. In
particular, we put three different types of depth estimation (supervised depth
prediction, self-supervised depth prediction, and self-supervised depth
completion) into a common framework. We integrate the corresponding networks
with a ConvLSTM such that the spatiotemporal structures of depth across frames
can be exploited to yield a more accurate depth estimation. Our method is
flexible. It can be applied to monocular videos only or be combined with
different types of sparse depth patterns. We carefully study the architecture
of the recurrent network and its training strategy. We are first to
successfully exploit recurrent networks for real-time self-supervised monocular
depth estimation and completion. Extensive experiments show that our recurrent
method outperforms its image-based counterpart consistently and significantly
in both self-supervised scenarios. It also outperforms previous depth
estimation methods of the three popular groups. Please refer to
https://www.trace.ethz.ch/publications/2020/rec_depth_estimation/ for details.Comment: Please refer to our webpage for details
https://www.trace.ethz.ch/publications/2020/rec_depth_estimation
End-to-end Lane Detection through Differentiable Least-Squares Fitting
Lane detection is typically tackled with a two-step pipeline in which a
segmentation mask of the lane markings is predicted first, and a lane line
model (like a parabola or spline) is fitted to the post-processed mask next.
The problem with such a two-step approach is that the parameters of the network
are not optimized for the true task of interest (estimating the lane curvature
parameters) but for a proxy task (segmenting the lane markings), resulting in
sub-optimal performance. In this work, we propose a method to train a lane
detector in an end-to-end manner, directly regressing the lane parameters. The
architecture consists of two components: a deep network that predicts a
segmentation-like weight map for each lane line, and a differentiable
least-squares fitting module that returns for each map the parameters of the
best-fitting curve in the weighted least-squares sense. These parameters can
subsequently be supervised with a loss function of choice. Our method relies on
the observation that it is possible to backpropagate through a least-squares
fitting procedure. This leads to an end-to-end method where the features are
optimized for the true task of interest: the network implicitly learns to
generate features that prevent instabilities during the model fitting step, as
opposed to two-step pipelines that need to handle outliers with heuristics.
Additionally, the system is not just a black box but offers a degree of
interpretability because the intermediately generated segmentation-like weight
maps can be inspected and visualized. Code and a video is available at
github.com/wvangansbeke/LaneDetection_End2End.Comment: Accepted at ICCVW 2019 (CVRSUAD-Road Scene Understanding and
Autonomous Driving
Characterising ChIP-seq binding patterns by model-based peak shape deconvolution.
International audienceBACKGROUND: Chromatin immunoprecipitation combined with massive parallel sequencing (ChIP-seq) is widely used to study protein-chromatin interactions or chromatin modifications at genome-wide level. Sequence reads that accumulate locally at the genome (peaks) reveal loci of selectively modified chromatin or specific sites of chromatin-binding factors. Computational approaches (peak callers) have been developed to identify the global pattern of these sites, most of which assess the deviation from background by applying distribution statistics. RESULTS: We have implemented MeDiChISeq, a regression-based approach, which - by following a learning process - defines a representative binding pattern from the investigated ChIP-seq dataset. Using this model MeDiChISeq identifies significant genome-wide patterns of chromatin-bound factors or chromatin modification. MeDiChISeq has been validated for various publicly available ChIP-seq datasets and extensively compared with other peak callers. CONCLUSIONS: MeDiChI-Seq has a high resolution when identifying binding events, a high degree of peak-assessment reproducibility in biological replicates, a low level of false calls and a high true discovery rate when evaluated in the context of gold-standard benchmark datasets. Importantly, this approach can be applied not only to 'sharp' binding patterns - like those retrieved for transcription factors (TFs) - but also to the broad binding patterns seen for several histone modifications. Notably, we show that at high sequencing depths, MeDiChISeq outperforms other algorithms due to its powerful peak shape recognition capacity which facilitates discerning significant binding events from spurious background enrichment patterns that are enhanced with increased sequencing depths
Transcriptome and protein analysis highlight the endosomal pathway in disease pathogenesis of metabolic CL syndrome
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Presentation and diagnosis of imported schistosomiasis: Relevance of eosinophilia, microscopy for ova, and serology
Background: In nonendemic countries a steady rise in cases of imported schistosomiasis has been observed. The objective of this study was to describe the presentation of patients diagnosed with schistosomiasis in the Outpatient Department (OPD) for Tropical Diseases in the Academic Medical Center, Amsterdam, the Netherlands. Methods: In a retrospective study, patients with schistosomiasis from our OPD (1997-1999), including a subgroup ol persons asking for screening for schistosomiasis and found positive, were analyzed. Diagnosis was based on freshwater exposure in an endemic area and positive serology for schistosomal antibodies. The following data were recorded: age, gender, country of birth, travel destination, symptoms, eosinophil count, and results of serology and stool and urine microscopy. Results: Seventy-eight patients (42 travelers, 16 expatriates, and 20 immigrants) were diagnosed with schisiosomiasis; 47% were infected in southern Africa. Twenty-four percent had specific symptoms, 57% had eosinophilia, and in 17 patients (22%) Schistosoma ova were found. Eleven travelers suffered from Katayama syndrome. Of the subgroup of 42 persons screened for schistosomiasis, 15 (36%) had schistosomal antibodies, the majority of these persons (10/15 [67%]) were infected in southern Africa. Conclusion: In our OPD schistosomiasis was diagnosed in about 26 patients per year, 3% of all new presentations. Infections were almost exclusively acquired in Africa. In travelers high eosinophilia was due to acute schistosomiasis; in immigants it was due to concomitant helminthic infections. One of three people asking to be screened for schistosomiasis had schistosomal antibodies. Eosinophilia was indicative but an insufficient screening tool, and stool and urine microscopy for ova were not sensitive. Screening by serology is easy and reliable and the method of choice in asymptomatic persons with a history of freshwater exposure in a high-risk are