Fraunhofer Society

About: Fraunhofer Society is a government organization based out in Munich, Germany. It is known for research contribution in the topics: Laser & Silicon. The organization has 24736 authors who have published 40168 publications receiving 820894 citations.

Single channel 1.28 Tbit/s and 2.56 Tbit/s DQPSK transmission

Abstract: By combining the techniques of optical TDM with polarisation multiplexing and DQPSK modulation format, 240 km transmission of 1.28 Tbit/s and 160 km transmission of 2.56 Tbit/s has been performed in a single wavelength channel.

Fraunhofer hhi at trecvid 2004: shot boundary detection system

Abstract: This paper describes the shot boundary detection and determination system developed at the Fraunhofer Institute for Telecommunications, Heinrich-HertzInstitut, used for the evaluation at TRECVID 2004. The system detects and determines the position of hard cuts, dissolves, fades, and wipes. It is very fast and has proved to have a very good detection performance. As input for our system, we use luminance pixel values of sub-sampled video data. The hard cut detector uses pixel and edge differences with an adaptive thresholding scheme. Flash detection and slow motion detection lower the false positive rate. Dissolve and fade detection is done with edge energy statistics, pixel and histogram differences, and a linearity measure. Wipe detection works with an evenness factor and double Hough transform. The difference between the submitted runs is basically only different threshold settings in the detectors, resulting in different recall and precision values.

Comparison of Maraging Steel Micro- and Nanostructure Produced Conventionally and by Laser Additive Manufacturing.

Abstract: Maraging steels are used to produce tools by Additive Manufacturing (AM) methods such as Laser Metal Deposition (LMD) and Selective Laser Melting (SLM). Although it is well established that dense parts can be produced by AM, the influence of the AM process on the microstructure—in particular the content of retained and reversed austenite as well as the nanostructure, especially the precipitate density and chemistry, are not yet explored. Here, we study these features using microhardness measurements, Optical Microscopy, Electron Backscatter Diffraction (EBSD), Energy Dispersive Spectroscopy (EDS), and Atom Probe Tomography (APT) in the as-produced state and during ageing heat treatment. We find that due to microsegregation, retained austenite exists in the as-LMD- and as-SLM-produced states but not in the conventionally-produced material. The hardness in the as-LMD-produced state is higher than in the conventionally and SLM-produced materials, however, not in the uppermost layers. By APT, it is confirmed that this is due to early stages of precipitation induced by the cyclic re-heating upon further deposition—i.e., the intrinsic heat treatment associated with LMD. In the peak-aged state, which is reached after a similar time in all materials, the hardness of SLM- and LMD-produced material is slightly lower than in conventionally-produced material due to the presence of retained austenite and reversed austenite formed during ageing.

Evaluation of current algorithms for segmentation of scar tissue from late Gadolinium enhancement cardiovascular magnetic resonance of the left atrium: an open-access grand challenge

Abstract: Background Late Gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) imaging can be used to visualise regions of fibrosis and scarring in the left atrium (LA) myocardium. This can be important for treatment stratification of patients with atrial fibrillation (AF) and for assessment of treatment after radio frequency catheter ablation (RFCA). In this paper we present a standardised evaluation benchmarking framework for algorithms segmenting fibrosis and scar from LGE CMR images. The algorithms reported are the response to an open challenge that was put to the medical imaging community through an ISBI (IEEE International Symposium on Biomedical Imaging) workshop.