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91.
The concept of Motif Combination was introduced in the French Automotive industry's R&W standard. There has however been no formal mathematical theory for the technique of motif combination. This paper sets out to develop this theory. The main result of the paper is a set of four properties that the motif combination rules must satisfy in order to have certain desirable metrological properties.Motif methods may well provide useful techniques which complement rather than replace the traditional approach based on a mean line. It was found that many functional problems could be simulated very efficiently using motif methods. Examples of functional simulation via motif combination are illustrated in the paper.  相似文献   
92.
Contents Surface charge accumulation and its decay at a GIS spacer are studied at atmospheric conditions employing a two step-calibration method. The results show that the accumulation saturates within 30 minutes; the dominant mechanism of surface charge accumulation is the drift of charged particles via air, while that of the decay is surface conduction. The characteristics are similar at both polarities.
Sättigungskonzentration und Abklingverhalten der Oberflächenladung an einem mit Gleichspannung beanspruchten Abstandshalter unter atmosphärischen Bedingungen
Übersicht Die Konzentration und das Abklingen von Oberflächenladungen an einem GIS Abstandshalter wurden unter atmosphärischen Bedingungen mit Hilfe eines zweistufigen Kalibrierungsverfahrens untersucht. Die Ergebnisse zeigen eine Sättigung der Ladungskonzentration innerhalb von 30 Minuten. Als Hauptursache der Ladungskonzentration ist die Drift geladener Teilchen in Luft anzusehen, während das Abklingen auf die Oberflächenleitung zurückzuführen ist. Ähnliche Charakteristiken ergeben sich mit beiden Polaritäten.
  相似文献   
93.
Three-dimensional, turbulent fluid flow analysis with computational methods has emerged as a viable tool in the design process of engine components for passenger cars. If applied in the early stages of the component development such analysis can help reduce the product development time drastically, and may support the design engineer to evaluate several competing design aspects before product completion. However the grid generation for complex geometries still poses a difficult and time consuming taks which strongly influences the accuracy of the numerical solution. The present paper studies the numerical solution of the flow in an inlet-manifold of a five-cylinder engine with two intake-ports for each cylinder. A fast and reliable grid generation technique is discussed in detail. The finite volume based Navier-Stokes solver with schemes of first and second order accuracy for the convective terms is used. Numerical results at several mass flow rates and different boundary conditions at the intake ports are compared with measurements. Finally, the computational results are discussed with respect to their applicability to support the design process of an inlet-manifold.  相似文献   
94.
IT/Business alignment   总被引:3,自引:2,他引:1  
Ohne Zusammenfassung
IT/Business alignment
  相似文献   
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Thermodynamic properties of aqueous solutions of both native and modified legumin of broad beans (Vicia faba L.) have been examined. A restricted trypsin-induced proteolysis was used to modify protein structure. Evaluation of protein affinity to ficoll in aqueous solutions showed that modified protein possessed higher hydrophilicity. Thermodynamic properties of diluted solutions were used to predict the phase behaviour in concentrated systems containing protein and ficoll. At specific concentrations of native legumin, the system can separate in two phases, whereas in the case of modified protein the single-phase behaviour of the system was predicted for any concentrations of both components. The experimental data obtained in concentrated systems confirmed predictions of thermodynamic analysis of diluted solutions.  相似文献   
98.
This contribution reviews the research work performed at the Johannes Kepler University of Linz, Austria, on the development of oscillators for the microwave and millimeter wave frequency range. This work, performed by the Microelectronics Institute and the Institute for Communications and Information Engineering, covers the range from low GHz frequencies up to 61 GHz and is devoted to applications like mobile communications and sensing. The active devices are based on gallium arsenide (GaAs), silicon germanium (SiGe), and Silicon (Si) and include Gunn-devices, bipolar transistors, and CMOS-technology.  相似文献   
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Our emphasis in this paper has been on the knowledge-based and cognitive issues pertinent for improved interactions between workers and manufacturing computer systems. We believe that these techniques are as necessary and applicable to manufacturing as to any other vocation, especially as the difference in collar color of shop people becomes less noticeable in their increasing role as knowledge workers.  相似文献   
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