207 research outputs found

    Conserving corporate knowledge for crankshaft design

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    A company's technical know-how which constitutes one of its most important assets often exists only in the heads of a small number of human experts. This limits the availability of this crucial resource and puts considerable strain on the respective experts. In cooperation with a German company^1 which produces motor-powered tools and vehicles a prototypical knowledge conservation system was developed which captures an individual expert's know-how about the design of crankshafts and makes it available to the whole design team. The knowledge-based system provides explanations of previous designs and supports unexperienced designers by suggesting viable alternatives. By checking the consistency between new cases and previously stated general design constraints, the system supports a continuous evolution of the stored knowledge which thus always reflects the current state of a company's technical know-how

    Integrated knowledge utilization and evolution for the conservation of corporate know-how

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    Insufficient consideration of knowledge evolution is a frequent cause for the failure of knowledge-based systems (KBSs) in industrial practice. Corporate know-how about the design and manufacturing of a particular product is subject to rather rapid changes, and it is hard to specify in advance exactly what information will be requested by various users. Keeping a KBS for the conservation of corporate know-how up-to-date or even enhancing its utility, thus requires the continuous monitoring of its performance, noting deficiencies, and suggestions for improvements. In the current paper, we discuss different ways in which information collected during knowledge utilization can be exploited for system evolution. We present structure-based rule and concept editors which allow for an immediate integration and formalization of new information, even by rather inexperienced users. A prototypical knowledge conservation system for crankshaft design which was developed in cooperation between the DFKI and a German company is used to illustrate and evaluate our approach

    Integrated knowledge utilization and evolution for the conservation of corporate know-how

    Get PDF
    Insufficient consideration of knowledge evolution is a frequent cause for the failure of knowledge-based systems (KBSs) in industrial practice. Corporate know-how about the design and manufacturing of a particular product is subject to rather rapid changes, and it is hard to specify in advance exactly what information will be requested by various users. Keeping a KBS for the conservation of corporate know-how up-to-date or even enhancing its utility, thus requires the continuous monitoring of its performance, noting deficiencies, and suggestions for improvements. In the current paper, we discuss different ways in which information collected during knowledge utilization can be exploited for system evolution. We present structure-based rule and concept editors which allow for an immediate integration and formalization of new information, even by rather inexperienced users. A prototypical knowledge conservation system for crankshaft design which was developed in cooperation between the DFKI and a German company is used to illustrate and evaluate our approach

    Developments for the calculation of heavily loaded journal bearings

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    This thesis describes the development of an ElastoHydroDynamic (EHD) bearing calculation. The effect of body forces is shown to be important for highly loaded bearings in reciprocating internal combustion engines. Extension of the program to rotating machinery includes an examination of instability in the shaft bearings of a turbocharger. The development of a parameter to predict cavitation damage in a bearing is promising. Several calculation results using the program are shown. These are engine main bearing and connecting rod big-end bearings and full floating bearings for a turbocharger. The calculations on the big-end bearing if a racing engine show why the designers were having difficulty understanding the correct location for the oil feed hole position. Effects of elastic deformation, thermal deformation and manufacturing/assembly deformation all have a significant effect on the extent of the oil film. A novel calculation for a cavitation damage parameter is demonstrated successfully for a heavily loaded diesel engine bearing. The importance of body forces on the oil film due to high accelerations on certain bearings is shown to be theoretically important but not yet demonstrated. The program was written with the intention to be incorporated into the sponsoring company’s range of engine design software. A part of that development process included carrying out calculations to demonstrate to customers and present papers at conferences. The results of some of these calculations have been included in this thesis. Results of a study on the effect of crankshaft geometry on racing engine viscous friction losses were reported in a paper presented at the IDETC conference in Long Beach, 2005. This study used the first version of the software which only included Rigid Hydro Dynamics (RHD) at the time but was usable. Results of a study on stability of shaft motion in high speed turbocharger bearings were reported in a paper at the 8th International Turbocharger conference in London, 2006. At this time the program was still only capable of RHD calculations but could now solve for multiple oil films simultaneously and sweep through the speed range. The studies on the effects of body forces and the development of a cavitation parameter will be presented in papers in the near future

    Verbmobil : translation of face-to-face dialogs

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    Verbmobil is a long-term project on the translation of spontaneous language in negotiation dialogs. We describe the goals of the project, the chosen discourse domains and the initial project schedule. We discuss some of the distinguishing features of Verbmobil and introduce the notion of translation on demand and variable depth of processing in speech translation. Finally, the role of anytime modules for efficient dialog translation in close to real time is described

    The refitting of plans by a human expert

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    During the course of the development of a Case-Oriented Expert System for situated applications additional cases were needed. The required cases were obtained by having a human expert refit old solutions to new problems and the structural relations between source and target cases were analyzed: A higher degree of reuse of the old cases was found when the expert could apply derivational reasoning and a uniform design rationale (i.e. the solution of the source was generated by the expert himself) than when the expert could only analyze structural relationships (i.e. the source solution was constructed by some one else). Except with very obvious cases, it was also found, that different experts perceive different cases as the most similar source to a given target problem. The results also indicate for user-situated applications of expert systems

    Theoretical consideration of goal recognition aspects for understanding information in business letters

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    Businesses are drowning in information - paper forms, e-mail, phone-calls and other media do struggle the speed of managers in handling and processing information. Traditional computer systems do not support business flow because of their inflexibility and their lack in understanding information. A sophisticated understanding of the meaning of a business letter requires an understanding of why the sender wrote it. This paper describes some ideas to use goal recognition techniques as one possibility, or method to initiate information understanding. It brings together two areas of cognition: goal recognition and document understanding. To do so, it gives an overview of the application of goal recognition techniques to the discovery of the overall purpose of a letter and a coherent explanation of how the individual sentences are meant to achieve that purpose

    Konzeption einer deklarativen Wissensbasis über recyclingrelevante Materialien

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    Das Recycling von Produkten und Produktionsreststoffen erlangt als Einflußfaktor für wirtschaftliche Entscheidungsprozesse eine immer größere Bedeutung. Die Integration von recyclingrelevanten Daten in betriebliche Informationsstrukturen sollte in Zukunft durch wissensbasierte Methoden unterstützt werden. Wir stellen Ansätze für eine Wissensbasis zur recyclinggerechten Produkt- und Produktionsplanung vor, und gehen dann genauer auf das grundlegende Modul über Materialien ein. Es wird untersucht, welche Evolutionstechniken sich zur Pflege derartiger Wissensbestände eignen, z.B. zur Validierung vorhandener und Exploration neuer Materialien im Hinblick auf ihre Recycelbarkeit

    Hierarchical skeletal plan refinement : task- and inference structures

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    This paper presents the task- and inference structure for skeletal plan refinement which was developed for lathe production planning, the application domain of the ARC-TEC project. Two inference structures are discussed: a global inference structure which was developed in the first phase of knowledge acquisition and a more detailed inference structure which builds on the hierarchical organization of the skeletal plans. The described models are evaluated with respect to their cognitive adequacy and their scope of application. The benefits and limitations of the KADS knowledge acquisition methodology are discussed with respect to the development of the two models
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