Convolutional-Based Encoder–Decoder Network for Time Series Anomaly Detection during the Milling of 16MnCr5

Machine learning methods have widely been applied to detect anomalies in machine and cutting tool behavior during lathe or milling. However, detecting anomalies in the workpiece itself have not received the same attention by researchers. In this article, the authors present a publicly available multivariate time series dataset which was recorded during the milling of 16MnCr5. Due to artificially introduced, realistic anomalies in the workpiece, the dataset can be applied for anomaly detection. By using a convolutional autoencoder as a first model, good results in detecting the location of the anomalies in the workpiece were achieved. Furthermore, milling tools with two different diameters where used which led to a dataset eligible for transfer learning. The objective of this article is to provide researchers with a real-world time series dataset of the milling process which is suitable for modern machine learning research topics such as anomaly detection and transfer learning

Auto-identification of dynamic axis models in machine tools

In metal-cutting manufacturing, ever smaller lot sizes lead to frequent changes in machining processes. For this, monitoring solutions help with setup and process optimization to achieve high quality and productivity at lower costs. For example, cutting forces may be monitored indirectly based on available data, like motor currents. However, this requires exact models of the individual dynamic behavior of machine axes. The determination of such models is time-consuming and cost-intensive. This paper presents an approach for the automatic identification of dynamic axis models, thus enabling an efficient deployment of force monitoring to a wide range of existing machines

Topoisomerase 3α and RMI1 Suppress Somatic Crossovers and Are Essential for Resolution of Meiotic Recombination Intermediates in Arabidopsis thaliana

Topoisomerases are enzymes with crucial functions in DNA metabolism. They are ubiquitously present in prokaryotes and eukaryotes and modify the steady-state level of DNA supercoiling. Biochemical analyses indicate that Topoisomerase 3α (TOP3α) functions together with a RecQ DNA helicase and a third partner, RMI1/BLAP75, in the resolution step of homologous recombination in a process called Holliday Junction dissolution in eukaryotes. Apart from that, little is known about the role of TOP3α in higher eukaryotes, as knockout mutants show early lethality or strong developmental defects. Using a hypomorphic insertion mutant of Arabidopsis thaliana (top3α-2), which is viable but completely sterile, we were able to define three different functions of the protein in mitosis and meiosis. The top3α-2 line exhibits fragmented chromosomes during mitosis and sensitivity to camptothecin, suggesting an important role in chromosome segregation partly overlapping with that of type IB topoisomerases. Furthermore, AtTOP3α, together with AtRECQ4A and AtRMI1, is involved in the suppression of crossover recombination in somatic cells as well as DNA repair in both mammals and A. thaliana. Surprisingly, AtTOP3α is also essential for meiosis. The phenotype of chromosome fragmentation, bridges, and telophase I arrest can be suppressed by AtSPO11 and AtRAD51 mutations, indicating that the protein is required for the resolution of recombination intermediates. As Atrmi1 mutants have a similar meiotic phenotype to Attop3α mutants, both proteins seem to be involved in a mechanism safeguarding the entangling of homologous chromosomes during meiosis. The requirement of AtTOP3α and AtRMI1 in a late step of meiotic recombination strongly hints at the possibility that the dissolution of double Holliday Junctions via a hemicatenane intermediate is indeed an indispensable step of meiotic recombination

The topoisomerase 3α zinc-finger domain T1 of Arabidopsis thaliana is required for targeting the enzyme activity to Holliday junction-like DNA repair intermediates

Topoisomerase 3α, a class I topoisomerase, consists of a TOPRIM domain, an active centre and a variable number of zinc-finger domains (ZFDs) at the C-terminus, in multicellular organisms. Whereas the functions of the TOPRIM domain and the active centre are known, the specific role of the ZFDs is still obscure. In contrast to mammals where a knockout of TOP3α leads to lethality, we found that CRISPR/Cas induced mutants in Arabidopsis are viable but show growth retardation and meiotic defects, which can be reversed by the expression of the complete protein. However, complementation with AtTOP3α missing either the TOPRIM-domain or carrying a mutation of the catalytic tyrosine of the active centre leads to embryo lethality. Surprisingly, this phenotype can be overcome by the simultaneous removal of the ZFDs from the protein. In combination with a mutation of the nuclease AtMUS81, the TOP3α knockout proved to be also embryo lethal. Here, expression of TOP3α without ZFDs, and in particular without the conserved ZFD T1, leads to only a partly complementation in root growth—in contrast to the complete protein, that restores root length to mus81-1 mutant level. Expressing the E. coli resolvase RusA in this background, which is able to process Holliday junction (HJ)-like recombination intermediates, we could rescue this root growth defect. Considering all these results, we conclude that the ZFD T1 is specifically required for targeting the topoisomerase activity to HJ like recombination intermediates to enable their processing. In the case of an inactivated enzyme, this leads to cell death due to the masking of these intermediates, hindering their resolution by MUS81

Involvement of the Cohesin Cofactor PDS5 (SPO76) During Meiosis and DNA Repair in Arabidopsis thaliana

Maintenance and precise regulation of sister chromatid cohesion is essential for faithful chromosome segregation during mitosis and meiosis. Cohesin cofactors contribute to cohesin dynamics and interact with cohesin complexes during cell cycle. One of these, PDS5, also known as SPO76, is essential during mitosis and meiosis in several organisms and also plays a role in DNA repair. In yeast, the complex Wapl-Pds5 controls cohesion maintenance and colocalizes with cohesin complexes into chromosomes. In Arabidopsis, AtWAPL proteins are essential during meiosis, however, the role of AtPDS5 remains to be ascertained. Here we have isolated mutants for each of the five AtPDS5 genes (A–E) and obtained, after different crosses between them, double, triple, and even quadruple mutants (Atpds5a Atpds5b Atpds5c Atpds5e). Depletion of AtPDS5 proteins has a weak impact on meiosis, but leads to severe effects on development, fertility, somatic homologous recombination (HR) and DNA repair. Furthermore, this cohesin cofactor could be important for the function of the AtSMC5/AtSMC6 complex. Contrarily to its function in other species, our results suggest that AtPDS5 is dispensable during the meiotic division of Arabidopsis, although it plays an important role in DNA repair by HR

Attribute Quality Management for Dynamic Identity and Access Management

Identity and access management (IAM) has become one main challenge for companies over the last decade. Most of the medium-sized and large organizations operate standardized IAM infrastructures in order to comply with regulations and improve the level of IAM automation. A recent trend is the application of attribute-based access control (ABAC) for automatically assigning permissions to employees. The success of ABAC, however, heavily relies on the availability of high-quality attribute definitions and values. Up to now, no structured attribute quality management approach for IAM environments exists. Within this paper, we propose TAQM, a comprehensive approach building on a tool-supported structured process for measuring and improvement of IAM data quality. During the evaluation of three real-life use cases within large industrial companies we underline the applicability of TAQM for the identification and cleansing of attribute errors by IT and non-IT experts as well as the general introduction of quality management processes for IAM

Framework for the Application of Industry 4.0 in Lithium-Ion Battery Cell Production

The application of Industry 4.0 in lithium-ion battery cell production enables companies to achieve increased product quality and global competitiveness, since the majority of value creation takes place in this process. Studies have shown, that improving production performance is the most effective way for battery cell manufacturers to become competitive in the increasingly globalized market. To achieve operational excellence, battery manufacturers must adopt the concepts of networked and digitized production. However, holistically introducing digitalization, data systems and Industry 4.0 methods in all sectors of lithium-ion battery cell production currently poses a major challenge as comprehensive approaches are not available. Therefore, a tailored methodology for the evaluation of suitability and introduction of digitalization and Industry 4.0 is presented. The approach addresses all production-related sectors from logistics to plant engineering to quality management via so called application areas. Multiple development stages divide these into the maturity levels in terms of Industry 4.0. To design each application area and stage, Industry 4.0 use cases from battery cell producers, plant manufacturers, and battery-related research projects are clustered and abstracted for general accessibility. It is shown, that abstracted application areas may be assigned either to all production sectors such as communication or to specific fields such as quality methods. Based on the application areas, corresponding toolboxes are established forming the core of a digitalization guide. To increase the level of maturity with regard to Industry 4.0, the presented paper aims at enabling companies to apply appropriate tools from the toolbox to their production. The systematic and efficient development and implementation of digitalization as well as the holistic assessment of a company's maturity are enabled and provide an essential tool towards increased competitiveness