Method for the engineering of production systems by reusing modules

Anlagenbauer und -betreiber unterliegen heute einem zunehmenden Wettbewerbsdruck, der zur Folge hat, dass die Effizienz in allen Unternehmensbereichen gesteigert werden soll. Die Wiederverwendung von Modulen und dem dazugehörigen Wissen ermöglicht die Steigerung der Effizienz und die Beherrschung der Komplexität im Engineering und auch in der Fertigung von komplexen und variantenreichen Produkten. Der Ansatz der Wiederverwendung ausdetaillierter Module aus Baukästen lässt sich bislang allerdings nur bedingt auf Produktionsanlagen wie Montagelinien übertragen, die spezifisch auf den Anforderungen und Prozesse des Anlagenbetreibers angepasst sind, da die notwendige Standardisierung beispielsweise für die Definition von Modulschnittstellen für diese Systeme sehr aufwändig ist. Die Herausforderung bei der Wiederverwendung von Modulen in solchen Produktionsanlagen liegt darin, Module zu identifizieren, die so klein sind, dass sie in verschiedenen Anlagen wiederverwandt werden können, und die so groß sind, dass sie dem Entwickler einen Mehrwert gegenüber der Wiederverwendung von Komponenten bieten. Um dieser Herausforderung gerecht zu werden, wird im Rahmen dieser Arbeit eine Methode vorgestellt werden, die Entwickler bei der Identifikation von Modulen unterstützt und die die Wiederverwendung in den frühen Phasen des Engineering – also in der Konzeption einer Anlage – ermöglicht. Dazu wird ein methodisches Vorgehen entwickelt und in einer Software implementiert. Die Methode ermöglicht es dem Entwickler, wiederverwendbare Module in bestehenden Produktionsanlagen zu identifizieren. Dazu wird ein matrixbasierter Ansatz in Kombination mit Sortieralgorithmen und Bewertungskriterien genutzt. Zusätzlich werden diese Module durch Eigenschaften und Funktionen systematisiert und in einer Wissensbasis abgespeichert. Dadurch wird es ermöglicht, im Engineering neuer Produktionsanlagen Modulkombinationen durch eine Prozessbeschreibung mit Funktionen zu erstellen und durch die Vorgabe von Eigenschaften relevante Kombinationen einzugrenzen. In einem weiteren Schritt werden die Module bewertet und damit die Modulkombinationen priorisiert. Dazu wird ein aggregierter Nutzwert aus Kosten, Produktivität, Energieverbrauch und Auslastung für die Modulkombination gebildet. Durch statistische Verfahren oder Simulation ist es möglich, diese Bewertungen an die Anforderungen an eine neue Produktionsanlage anzupassen. Um den Entwickler bei der Anwendung der Methode zu unterstützen, wurde die Methode in einem Softwarewerkzeug abgebildet und in der industriellen Praxis erprobt. Die vorgestellte Methode eignet sich insbesondere für Hersteller und Betreiber prozessspezifischer Produktionsanlagen, die das Wissen über diese Anlagen im Engineering neuer oder im Reengineering bestehender Anlagen wiederverwenden wollen. Die Methode unterstützt sie nicht nur bei der Modulidentifikation und bei der Systematisierung des Wissens, sondern auch in der Bereitstellung während der Konzeptionsphase. Im Engineering wird neben der Auswahl einer geeigneten Modulkombination auch eine Bewertung vorgenommen, die in weiterführenden Schritten wie der Angebotserstellung genutzt werden kann. Der Nutzen der Wiederverwendung von Wissen wird durch die Bereitstellung von Daten zu den Modulen erhöht.Industrial machine manufacturers and operating companies are subject to an increasing competition nowadays. This results in the pursuit of greater efficiency and effectiveness in all areas of the company. The reuse of modules and the related knowledge allows increasing the efficiency and managing the complexity in engineering and in the production of complex products with many variants. The approach of reusing modules from modular systems, which are described in all details, can be transmitted only partially on production systems such as assembly lines so far. These systems are specifically adapted to the requirements and processes of the operator of the production system. This is mainly due to the standardization effort for example for the definition of module interfaces for these systems. The challenge of reuse of modules in such a production system is to identify modules which are small enough that they can be reused in different systems, and which are large enough that they offer the developer an added value, compared to the reuse of components. In this thesis, a method will be presented in order to meet this challenge. This method supports the engineer in the identification of modules, and it facilitates the reuse in the early stages of engineering or, more specifically, in the conception of a system. For this, a methodology is developed and implemented as software. The method allows the developer to identify reusable modules into existing production systems. For this purpose, a matrix-based approach is used in combination with sorting algorithms and evaluation criteria. In addition, these modules are systematized by features and functions and stored in a knowledge base. Thus, it is possible to create combinations of modules through a process description with functions in the engineering of new production and to limit the selection to relevant combinations by specifying properties. In a further step, the modules are assessed and thus the module combinations are prioritized. For this purpose, an aggregate utility value of cost, productivity, energy consumption and utilization is formed for the module combination. It is possible through statistical methods or simulation to adapt these assessments to the requirements of a new production system. The method is implemented in a software tool to assist the developer in the application of the method and tested in the industrial practice. The method is particularly suitable for manufacturers and operators of process-specific production system, who want to reuse the knowledge of these systems in the engineering of new systems or the adaption of existing systems. The method supports the user not only in the identification of modules and in the systematization of knowledge, but also in the provision of knowledge during the conceptual design phase. In addition to choosing a suitable combination of modules an assessment is carried out in engineering, which can be used in further steps, such as the quotation. The benefits of reuse of knowledge are increased by the provision of data of the modules. Due to this this knowledge can be reused not only for the modules, the interfaces and the assessment, but also on first drafts, documentation, simulation models etc.

Fast Bayesian Optimization of Machine Learning Hyperparameters on Large Datasets

Bayesian optimization has become a successful tool for hyperparameter optimization of machine learning algorithms, such as support vector machines or deep neural networks. Despite its success, for large datasets, training and validating a single configuration often takes hours, days, or even weeks, which limits the achievable performance. To accelerate hyperparameter optimization, we propose a generative model for the validation error as a function of training set size, which is learned during the optimization process and allows exploration of preliminary configurations on small subsets, by extrapolating to the full dataset. We construct a Bayesian optimization procedure, dubbed Fabolas, which models loss and training time as a function of dataset size and automatically trades off high information gain about the global optimum against computational cost. Experiments optimizing support vector machines and deep neural networks show that Fabolas often finds high-quality solutions 10 to 100 times faster than other state-of-the-art Bayesian optimization methods or the recently proposed bandit strategy Hyperband

DNA as Tunable Adaptor for siRNA Polyplex Stabilization and Functionalization

siRNA and microRNA are promising therapeutic agents, which are engaged in a natural mechanism called RNA interference that modulates gene expression posttranscriptionally. For intracellular delivery of such nucleic acid triggers, we use sequence-defined cationic polymers manufactured through solid phase chemistry. They consist of an oligoethanamino amide core for siRNA complexation and optional domains for nanoparticle shielding and cell targeting. Due to the small size of siRNA, electrostatic complexes with polycations are less stable, and consequently intracellular delivery is less efficient. Here we use DNA oligomers as adaptors to increase size and charge of cargo siRNA, resulting in increased polyplex stability, which in turn boosts transfection efficiency. Extending a single siRNA with a 181-nucleotide DNA adaptor is sufficient to provide maximum gene silencing aided by cationic polymers. Interestingly, this simple strategy was far more effective than merging defined numbers (4-10) of siRNA units into one DNA scaffolded construct. For DNA attachment, the 3' end of the siRNA passenger strand was beneficial over the 5' end. The impact of the attachment site however was resolved by introducing bioreducible disulfides at the connection point. We also show that DNA adaptors provide the opportunity to readily link additional functional domains to siRNA. Exemplified by the covalent conjugation of the endosomolytic influenza peptide INF-7 to siRNA via a DNA backbone strand and complexing this construct with a targeting polymer, we could form a highly functional polyethylene glycol-shielded polyplex to downregulate a luciferase gene in folate receptor-positive cells

Self-configuring resource management in cooperative and uncooperative autonomous systems

In several circumstances, cooperation among autonomous agents is a prerequisite for effective or efficient task processing. This stems from the inherent or transient asymmetry of the agents resources and capabilities. Since agents process tasks autonomously, they have to decide by themselves under which conditions and to which means they cooperate. Such local decision making renders dedicated entities for resource management dispensable and, thus, may increase the systems fault-tolerance. In this report, we propose a framework for self-configuring resource management in cooperative and uncooperative environments. Therefore, we recognize the relatedness of autonomous agents and economic entities. Both are REMMs assess their resources and demands locally which leads to more efficiency of the overall system. We identify and discuss two dimensions of autonomy, i.e. principal-agent and inter-agent autonomy

Entropy conservative high-order fluxes in the presence of boundaries

In this paper, we propose a novel development in the context of entropy stable finite-volume/finite-difference schemes. In the first part, we focus on the construction of high-order entropy conservative fluxes. Already in [LMR2002], the authors have generalized the second order accurate entropy conservative numerical fluxes proposed by Tadmor to high-order ($2p$) by a simple centered linear combination. We generalize this result additionally to non-centered flux combinations which is in particular favorable if non-periodic boundary conditions are needed. In the second part, a Lax-Wendroff theorem for the combination of these fluxes and the entropy dissipation steering from [Klein2022] is proven. In numerical simulations, we verify all of our theoretical findings

Large two-level magnetoresistance effect in doped manganite grain boundary junctions

We performed a systematic analysis of the tunneling magnetoresistance (TMR) effect in single grain boundary junctions formed in epitaxial La(2/3)Ca(1/3)MnO(3) films deposited on SrTiO(3) bicrystals. For magnetic fields H applied parallel to the grain boundary barrier, an ideal two-level resistance switching behavior with sharp transitions is observed with a TMR effect of up to 300% at 4.2 K and still above 100% at 77 K. Varying the angle between H and the grain boundary results in differently shaped resistance vs H curves. The observed behavior is explained within a model of magnetic domain pinning at the grain boundary interface.Comment: 4 pages, 3 figures, to appear in Phys. Rev. B (Rapid Comm.

Transport anisotropy in biaxially strained La(2/3)Ca(1/3)MnO(3) thin films

Due to the complex interplay of magnetic, structural, electronic, and orbital degrees of freedom, biaxial strain is known to play an essential role in the doped manganites. For coherently strained La(2/3)Ca(1/3)MnO(3) thin films grown on SrTiO(3) substrates, we measured the magnetotransport properties both parallel and perpendicular to the substrate and found an anomaly of the electrical transport properties. Whereas metallic behavior is found within the plane of biaxial strain, for transport perpendicular to this plane an insulating behavior and non-linear current-voltage characteristics (IVCs) are observed. The most natural explanation of this anisotropy is a strain induced transition from an orbitally disordered ferromagnetic state to an orbitally ordered state associated with antiferromagnetic stacking of ferromagnetic manganese oxide planes.Comment: 5 pages, 4 figure

Lanes. A lightweigth overlay for service discovery in mobile ad hoc networks

The ability to discover services offered in a mobile ad hoc network is the major prerequisite for effective usability of these networks. Unfortunately, existing approaches to service trading are not well suited for these highly dynamic topologies since they either rely on centralized servers or on resource-consuming query flooding. Application layer overlays seem to be a more promising approach. However, existing solutions like the Content-Addressable Network (CAN) are especially designed for internet based peer-to-peer networks yielding structural conditions that are far too complex for ad hoc networks. Therefore, in this paper, we propose a more lightweight overlay structure: lanes. We present algorithms to correct and optimize its structure in case of topology changes and show how it enables the trading of services specified by arbitrary descriptions