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31.
32.
We consider large-scale dynamical systems in which both the initial state and some parameters are unknown. These unknown quantities must be estimated from partial state observations over a time window. A data assimilation framework is applied for this purpose. Specifically, we focus on large-scale linear systems with multiplicative parameter-state coupling as they arise in the discretization of parametric linear time-dependent partial differential equations. Another feature of our work is the presence of a quantity of interest different from the unknown parameters, which is to be estimated based on the available data. In this setting, we employ a simplicial decomposition algorithm for an optimal sensor placement and set forth formulae for the efficient evaluation of all required quantities. As a guiding example, we consider a thermo-mechanical PDE system with the temperature constituting the system state and the induced displacement at a certain reference point as the quantity of interest. 相似文献
33.
Natasa Vujica Herzog Stefano Tonchia Andrej Polajnar 《Computers & Industrial Engineering》2009,57(3):963-975
An empirical analysis is presented for researching linkages between manufacturing strategy, benchmarking, performance measurement (PM) and business process reengineering (BPR). Although the importance of these linkages has been described in conceptual literature, it has not been widely demonstrated empirically. The survey research was carried out in 73 medium and large-sized Slovenian manufacturing companies within the mechanical, electro-mechanical and electronic industries. The resulting data were subjected to reliability and validity analyses. Canonical correlation analysis was used to test six hypotheses.The results confirmed the need for a strategically-driven BPR approach and the positive impact of performance measurement on BPR performance. 相似文献
34.
Semi-interpenetrating networks (sIPNs) designed to mimic extracellular matrix via covalent crosslinking of poly(ethylene glycol)
diacrylate in the presence of gelatin have been shown to aid in wound healing, particularly when loaded with soluble factors.
Ideal systems for tissue repair permit an effective release of therapeutic agents and flow of nutrients to proliferating cells.
Appropriate network characterization can, consequently, be used to convey an understanding of the mass transfer kinetics necessary
for materials to aid in the wound healing process. Solute transport from and through sIPNs has not yet been thoroughly evaluated.
In the current study, the diffusivity of growth factors and nutrients through the polymeric system was determined. Transport
of keratinocyte growth factor was modeled by treating the sIPN as a plane sheet into which the protein was loaded. The diffusion
coefficient was determined to be 4.86 × 10−9 ± 1.86 × 10−12 cm2/s. Glucose transport was modeled as flow through a semi-permeable membrane. Using lag-time analysis, the diffusion coefficient
was calculated to be 2.25 × 10−6 ± 1.98 × 10−7 cm2/s. The results were evaluated in conjunction with previous studies on controlled drug release from sIPNs. As expected from
Einstein-Stokes equation, diffusivity decreased as molecular size increased. The results offer insight into the structure-function
design paradigm and show that release from the polymeric system is diffusion controlled, rather than dissolution controlled. 相似文献
35.
Rudolf Herzog 《?sterreichische Wasser- und Abfallwirtschaft》2009,61(11-12):a30-a33
36.
J. Herzog 《e & i Elektrotechnik und Informationstechnik》2002,119(10):a29
Firmen&;ProdukteUMTS-Markt
Leises Hohlseil 相似文献37.
Bernd Trummer Otto Fruhwirth Klaus Reichmann Gerhard Herzog Werner Sitte Michael Holzinger 《Journal of Electroceramics》2000,5(1):53-61
Conductive LaNiO3 thin film electrodes were deposited by chemical solution deposition (CSD) from nitrate solutions onto polycrystalline Al2O3 and (Ba,Ca)TiO3 PTCR ceramic substrates. The electrical properties of the LaNiO3 thin film on Al2O3 and of the interface consisting of LaNiO3 and the semiconductive oxide ceramic were investigated. The deposited LaNiO3 films were about 250 nm thick and consisted of nanosized particles. The resistivity of the LaNiO3 film was about 3 × 10-3cm at 20°C. The PTCR ceramic consisted of m sized particles and exhibited an electronic resistivity of about 10 cm at 20°C and a steep increase of the resistivity of a few orders of magnitude above the Curie point at about 120°C. The electrical properties of the LaNiO3/PTCR interface were dominated by the properties of a barrier layer between the PTCR ceramic and the LaNiO3 electrode. The potential dependence of the impedance indicated that the barrier layer consisted of a depletion layer within the PTCR ceramic, when the flat band potential of LaNiO3 on the PTCR ceramic at about –250 mV was exceeded. Additionally the formation of an insulating layer at the LaNiO3 electrode has to be taken into account. 相似文献
38.
This article attempts to show how computer graphics can assist in computerized development of project-type schedules as exemplified by preventive maintenance scheduling in the electric power industry. The method is equally applicable to the scheduling of maintenance activities in general or, with modification, to devising shift schedules for personnel such as police, nurses, and toll collectors who must provide 24-hour service with changing demand levels. A hand procedure currently used by electric utilities for creating preventive maintenance shutdown schedules for generator units is first described. A mixed integer programming model of the problem is given which is computationally intractable for any realistic-size problems. The same problem using man-machine interaction via a graphics terminal to overcome the computational limitations of the mathematical formulation is then described and illustrated. A proposed extension to improve the speed of solution is also described. 相似文献
39.
Industrial control systems have unique system requirements which often require diverse systems of cooperating components to achieve system goals. System requirements may be specified in the form of tasks which must be executed in sequential order. This paper presents a design perspective in which such problems can be decomposed and implemented by a distributed system in a modular-fashion. A System Scheduler is responsible for all flow control functions. Loosely coupled Task Processors respond to instructions from the scheduler to perform the control algorithm Parallelism, redundancy, and distributed control are presented as methods of improving system performance and reliability. 相似文献
40.
Studies of the effect of cholecystokinin (CCK) on hepatic elimination of intravenously administered iopanoate and on gallbladder opacification were performed using nonoperated dogs with intact enterohepatic circulation and normal endogenous bile salt pool. Intravenous administration of CCK (3 units/kg) resulted in a 32% increase in apparent transport maximum (maximum rate of elimination) of iopanoate and earlier and enhanced gallbladder opacification. This increase in apparent transport maximum was abolished by cholecystectomy, indicating that the increase was a result of the release of bile salts from the gallbladder rather than a direct effect of the hormone on the hepatic elimination of iopanoate. The early gallbladder opacification and increased density of contrast material in the gallbladder were related to CCK-induced emptying of the gallbladder and subsequent filling with opacified bile. 相似文献