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Matyas K.,Vienna University of Technology | Auer S.,Fraunhofer Austria Research GmbH
CIRP Annals - Manufacturing Technology | Year: 2012

Medium-term sales and operations as well as medium to short-term production planning in customer order driven production processes are performed using a cascading planning process. A lack of coordination and feedback between different planning phases causes problems with a negative effect on costs in production that originate from unfeasible production programs. Based on a system for the classification of planning restrictions the planning process will be controlled utilizing a newly developed combination of the methods of Linear Programming and Constraint Programming. The result is a formal logic to combine the different planning horizons and the two sets of planning methods. © 2012 CIRP. Source

Ullrich T.,Fraunhofer Austria Research GmbH | Schinko C.,Graz University of Technology | Schiffer T.,Graz University of Technology | Fellner D.W.,TU Darmstadt
Applied Geomatics | Year: 2013

Within the last few years, generative modeling techniques have gained attention especially in the context of cultural heritage. As a generative model describes a rather ideal object than a real one, generative techniques are a basis for object description and classification. This procedural knowledge differs from other kinds of knowledge, such as declarative knowledge, in a significant way: It is an algorithm, which reflects the way objects are designed. Consequently, generative models are not a replacement for established geometry descriptions (based on points, triangles, etc.) but a semantic enrichment. In combination with variance analysis techniques, generative descriptions can be used to validate reconstructions. Detailed mesh comparisons can reveal smallest changes and damages. These analysis and documentation tasks are needed not only in the context of cultural heritage but also in engineering and manufacturing. Our contribution to this problem is a work flow, which automatically combines generative/procedural descriptions with reconstructed artifacts and performs a nominal/actual value comparison. The reference surface is a procedural model whose accuracy and systematics describe the semantic properties of an object, whereas the actual object is a real-world data set (laser scan or photogrammetric reconstruction) without any additional semantic information. © Società Italiana di Fotogrammetria e Topografia (SIFET) 2013. Source

Jaeger A.,Fraunhofer Austria Research GmbH | Jaeger A.,Vienna University of Technology | Matyas K.,Vienna University of Technology
Production Engineering | Year: 2016

The purpose of this paper is to provide an enabler-based approach for a supervised self-assessment of operations excellence (OsE). Based on the latest approaches of excellence in operations from the literature as well as on the philosophy of the EFQM model, an OsE working definition was developed. In contrast to operational excellence (OE), which deals exclusively with the optimization of result driven processes, OsE promotes the enhancement of operation-specific enablers and linked results. The evaluation of crucial cause–effect relationships of relevant enabler and result criteria supports the determination of a company’s capability to achieve sustainability and excellence in terms of its operations. To foster a methodical integration of OsE in organizations, a phase model for a systematic assessment process was designed and verified with 24 companies in the Austrian machinery and metalware industries. © 2016 The Author(s) Source

Barmak K.,Carnegie Mellon University | Eggeling E.,Fraunhofer Austria Research GmbH | Emelianenko M.,George Mason University | Epshteyn Y.,University of Utah | And 3 more authors.
Physical Review B - Condensed Matter and Materials Physics | Year: 2011

Mesoscale experiment and simulation permit harvesting information about both geometric features and texture in polycrystals. The grain boundary character distribution (GBCD) is an empirical distribution of the relative length [in two dimensions (2D)] or area (in 3D) of an interface with a given lattice misorientation and normal. During the growth process, an initially random distribution of boundary types reaches a steady state that is strongly correlated to the interfacial energy density. In simulation, it is found that if the given energy density depends only on lattice misorientation, then the steady-state GBCD and the energy are related by a Boltzmann distribution. This is among the simplest nonrandom distributions, corresponding to independent trials with respect to the energy. In this paper, we derive an entropy-based theory that suggests that the evolution of the GBCD satisfies a Fokker-Planck equation, an equation whose stationary state is a Boltzmann distribution. Cellular structures coarsen according to a local evolution law, curvature-driven growth, and are limited by space-filling constraints. The interaction between the evolution law and the constraints is governed primarily by the force balance at triple junctions, the natural boundary condition associated with curvature-driven growth, and determines a dissipation relation. A simplified coarsening model is introduced that is driven by the boundary conditions and reflects the network level dissipation relation of the grain growth system. It resembles an ensemble of inertia-free spring-mass dashpots. Application is made of the recent characterization of Fokker-Planck kinetics as a gradient flow for a free energy in deriving the theory. The theory predicts the results of large-scale two-dimensional simulations and is consistent with experiment. © 2011 American Physical Society. Source

Ullrich T.,Fraunhofer Austria Research GmbH | Settgast V.,Fraunhofer Austria Research GmbH | Berndt R.,University of Graz
ELPUB 2010 - Publishing in the Networked World: Transforming the Nature of Communication, 14th International Conference on Electronic Publishing | Year: 2010

With increasing knowledge the process of knowledge management and engineering becomes more and more important. Enriching documents by using markup techniques and by supporting semantic annotations is a major technique for knowledge management. This invaluable information is of extreme importance in the context of civil engineering, product life cycle management, virtual archival storage, and preservation. In these fields of applications annotation techniques for 3D documents are a vital part. They provide semantic information that makes up the basis for digital library services: retrieval, indexing, archival, and searching. Furthermore, metadata are of significant importance as they set the stage for data re-use and they provide documentation of data sources and quality, which is vital for every engineering department. Using metadata helps the user to understand data. Additional information allows focusing on key elements of data that help to determine the data's fitness for a particular use and may provide consistency in terminology. In this paper we give an overview on state-of-the-art annotation techniques focussed on 3D data. Source

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