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111.
The identification of plant-wide faults is a very important topic as it enables plant operators to decrease rejections or to increase the product quality. This paper shows a fault propagation approach for this field of interest based on time delay estimation. Due to the fact that the estimation of time delays in multiple-input single-output systems or nonlinear systems is either impossible or very difficult with known methods, a new method based on k nearest neighbor imputation was developed and is validated in this paper theoretically. The effectiveness of the identification algorithm is demonstrated on several simulations and on an industrial hydrocracker plant. 相似文献
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Makrina A. Chairopoulou Alex Schreiber Fabian Kratzer Sebastian Wolf Ulrich Teipel 《化学,工程师,技术》2020,92(4):405-413
As a waste product, oyster shells pose a major environmental pollution problem and the reuse of the material is becoming increasingly important. Since the comminution process in the recycling of secondary raw materials defines the properties of the material, oyster shells were grinded using a planetary ball mill and an impact mill and the fractions obtained were analyzed in terms of size and shape and compared with each other. A comminuted material from the impact mill was used for a series of wetting experiments, which helped to demonstrate the surface free energy of the material. 相似文献
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Shunsuke Kato Prof. Akira Onoda Naomasa Taniguchi Prof. Ulrich Schwaneberg Prof. Takashi Hayashi 《Chembiochem : a European journal of chemical biology》2021,22(4):679-685
Directed evolution of Cp*RhIII-linked nitrobindin (NB), a biohybrid catalyst, was performed based on an in vitro screening approach. A key aspect of this effort was the establishment of a high-throughput screening (HTS) platform that involves an affinity purification step employing a starch-agarose resin for a maltose binding protein (MBP) tag. The HTS platform enables efficient preparation of the purified MBP-tagged biohybrid catalysts in a 96-well format and eliminates background influence of the host E. coli cells. Three rounds of directed evolution and screening of more than 4000 clones yielded a Cp*RhIII-linked NB(T98H/L100K/K127E) variant with a 4.9-fold enhanced activity for the cycloaddition of acetophenone oximes with alkynes. It is confirmed that this HTS platform for directed evolution provides an efficient strategy for generating highly active biohybrid catalysts incorporating a synthetic metal cofactor. 相似文献
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Detection of UF resin on wood particles and in particleboards: potential of selected methods for practice-oriented offline detection 总被引:1,自引:0,他引:1
Martin Riegler Wolfgang Gindl-Altmutter Markus Hauptmann Ulrich Müller 《Holz als Roh- und Werkstoff》2012,70(6):829-837
In the wood-based panel industry, controlling the manufacturing process is crucial for ensuring product quality, using resources efficiently and cutting production costs. One major aspect for the final quality of particleboards is the distribution of resin on particles within a board. This study deals with the comparison of techniques that can be used for a practice-oriented detection of urea formaldehyde resin within an industrial environment. Resin detection was carried out by staining the resin with visible and fluorescent dyes as well as by near infrared spectroscopic (NIR) in combination with CHN elemental analysis. Using the fluorescent dye Brilliant Sulphaflavine, resin as well as single resin droplets could be detected best. NIR measurements did not lead to coherent results and should be further improved, especially because of its potential for online detection. 相似文献
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p‐type TCOs for use in transparent electronics In this article, a new type of semiconducting material is introduced. Transparent conducting thin films are already established in our everydaylife. But the type of these so‐called ?TCOs”? is dominated by electron transport, that means they are n‐type. To get transparent p‐n‐junctions and therefore transparent electronics, the missing part is a transparent p‐type material. Researchers all over the world have found different approach to produce this new generation of materials. At the Fraunhofer Institute for Surface Engineering and Thin Films (IST) in Braunschweig it is now possible to produce these kind of thin films as well. 相似文献
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Designing a profitable flight schedule is a highly complex planning problem. Both passenger and cargo airlines usually follow a decomposition approach and break this problem into several subproblems which are then solved consecutively and iteratively using specific but isolated models. At cargo airlines, the four major interdependent decision problems are flight selection, fleet assignment, rotation planning, and cargo routing. In our research, we have developed a planning approach which differs from other OR-based planning approaches in two aspects. The approach is based on integrated models and it is based on the pragmatic planning paradigm to optimally modify an existing schedule. For this purpose, the planner has to identify mandatory and optional flights. Then the planning goal is to identify the best combination of optional flights to be included into the schedule. Our integrated planning models comprise several additional important planning aspects for cargo airlines such as available capacities on external flights (e.g. belly capacities from passenger flights or road-feeder services), cargo handling costs and constraints, and aircraft maintenance regulations. There are two main aspects which we present in this paper. First, we describe the planning problem and the specific planning paradigm, develop a set of complex mixed-integer programs representing the different subproblems, and finally present integrated problem formulations as well as several model extensions. Thereafter, we develop a branch and price and cut approach for solving the mathematical programs and present extensive computational results obtained for a set of generated yet highly practical problem instances for different types of carriers. The results show that our approach is able to find high quality solutions to problem instances of realistic size and complexity within reasonable time. 相似文献