Konferenzbeiträge

Recent research has shown that the joint processing of simultaneously recorded EEG-MEG signals can be beneficial compared to the separate analysis of data if the corresponding tensors have one of their factor matrices in common. In this study, we perform a joint CP decomposition of simultaneously recorded EEG and MEG magnetometer as well as gradiometer measurements via a new extension of the coupled SEmi-Algebraic framework for the approximate CP decomposition via SImultaneous matrix diagonalization (SECSI) to jointly factorize several tensors with at least one factor matrix in common. In case of the biomedical data, the four measured tensors have the factor matrix in the frequency domain in common. The developed coupled SECSI algorithm allows extracting the signal sources even in ill-conditioned scenarios. In the final processing step, coupled SECSI chooses the best out of a variety of possible factor matrix estimates, i.e., a combination that leads to the smallest value of the reconstruction error. However, for data tensors that do not exhibit significant coupling, the uncoupled solution can also be selected. The results are evaluated on measured as well as on synthetic data and compared with other state-of-the-art approaches.

The demand for efficient and digital systems for supporting the decision making during the design of a product is a key issue in manufacturing companies. Decisions made during the development and design of a product have a strong impact on the costs and delivery times of a product. Hence, a digital system which supports the engineer during and after the development process with information about the manufacturability of the product can reduce the production costs and times. In order to be able to evaluate the manufacturing capabilities at manufacturing process and machine level, there is a need to represent them in a digital way. Digital knowledge bases like taxonomies and ontologies provide the possibility for a representation of manufacturing resources. The state of the art shows different approaches for the use of ontologies in the domain of subtractive manufacturing processes as well as additive manufacturing (AM) processes. The goal of this work is the semantical representation of manufacturing technology capabilities with focus on AMmachines and processes. In this paper we introduce taxonomies of Manufacturing Features and Manufacturing Restrictions which were developed in accordance with current standards. To enrich the taxonomies with information, it was enhanced by relations between different manufacturing related entities in a knowledge graph. If manufacturing processes and machines can be digitally mapped, described and linked to the geometric information of a product together with information on the current performance of the company/network, bottlenecks and delivery delays during the manufacturing of parts can be avoided.

The hardness of coating materials such as tin or gold is temperature-dependent, so the contact area and thus the contact resistance change depending on the temperature. Contact resistance measurements are carried out on hard gold- and tin-coated connector contacts at elevated temperatures. It is shown that the contact resistance decreases significantly with increasing temperature. Tests are also being carried out with solid and stranded copper wires. In addition to the hardness, foreign layers on the copper conductors have a further influence on the contact resistance.

The design of a multistatic ultra-wideband (UWB) microwave radar imaging system for breast cancer detection is presented in this paper. Based on pseudo-noise code (M-sequence) technology, this multiple-input-multiple-output (MIMO) system includes 24 antennas and records data from 12S channels. Furthermore, it realizes complete rotation of the antenna array around the breast, which allows several options of clutter removal and differential imaging, respectively. The system underwent a first feasibility study on volunteers at University Hospital Jena. The procedure of examination and first experiences are described in this paper.