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81.
Heiko Koziolek Andreas Burger Marie Platenius-Mohr Julius Rückert Francisco Mendoza Roland Braun 《Software》2020,50(3):246-274
Distributed control systems are currently evolving towards industrial Internet of Things (IoT) systems communicating fully using Internet protocols. This creates opportunities for streamlining costly commissioning processes, which today require substantial manual work for installing, configuring, and integrating thousands of actuators and sensors. The vision of “plug-and-produce” control systems has been pursued for more than 15 years, but existing approaches fell short regarding configuration tasks and vendor neutrality. This paper introduces the standards-based IoT reference architecture OpenPnP, which allows largely automating the configuration and integration tasks of industrial commissioning processes. The architecture includes a number of design and technology decisions and the required implementation can be scaled down to resource-constrained industrial devices. This paper demonstrates how OpenPnP can reduce configuration and integration efforts up to 90% in typical settings, while potentially scaling well up to tens of thousands of communicated signals. Practitioners can orient their implementations towards OpenPnP, therefore potentially enabling “plug-and-produce” in many thousands of control systems. 相似文献
82.
Instance matching is the problem of determining whether two instances describe the same real-world entity or not. Instance matching plays a key role in data integration and data cleansing, especially for building a knowledge base. For example, we can regard each article in encyclopedias as an instance, and a group of articles which refers to the same real-world object as an entity. Therefore, articles about Washington should be distinguished and grouped into different entities such as Washington, D.C (the capital of the USA), George Washington (first president of the USA), Washington (a state of the USA), Washington (a village in West Sussex, England), Washington F.C. (a football club based in Washington, Tyne and Wear, England), Washington, D.C. (a novel). In this paper, we proposed a novel instance matching approach Active Instance Matching with Pairwise Constraints, which can bring the human into the loop of instance matching. The proposed approach can generate candidate pairs in advance to reduce the computational complexity, and then iteratively select the most informative pairs according to the uncertainty, influence, connectivity and diversity of pairs. We evaluated our approach one two publicly available datasets AMINER and WIDE-NUS and then applied our approach to the two large-scale real-world datasets, Baidu Baike and Hudong Baike, to build a Chinese knowledge base. The experiments and practice illustrate the effectiveness of our approach. 相似文献
83.
Zusammenfassung In Anlehnung an die Arbeiten von H.C. Hottel und Mitarbeitern wird für zylindrische Brennkammern ein vereinfachtes Verfahren
zur Berechnung des Temperaturfeldes und der ?rtlichen W?rmeübertragung entwickelt. Grundlage der Strahlungsaustauschrechnungen
sind die direkten Austauschfaktoren. Zum Berücksichtigen des Str?mungs- und des Ausbrandverlaufs dienen einfache Modelle.
Ein neuentwickeltes Verfahren erm?glicht die Berechnung der Absorptionskoeffizienten des Rauchgases als Bandenstrahler. Rechenergebnisse
für die W?rmeübertragung werden mit an der Brennkammer des Erhitzers einer geschlossenen Gasturbine gewonnen Versuchsergebnissen
verglichen. Das Verfahren bietet Vorteile für Parameterstudien bei Neuauslegungen.
Diese Untersuchungen wurden von der Deutschen Forschungsgemeinschaft, Bad Godesberg, unterstützt. 相似文献
84.
Tesfaye?BayeEmail author Heiko?C.?Becker 《Journal of the American Oil Chemists' Society》2004,81(7):641-645
Vernonia galamensis is a potential new industrial oilseed crop from the Asteraceae family. The interest in this species is due to the presence
of a high vernolic acid content of its seed oil, which is useful in the oleochemical industry for paints and coatings. The
development of a rapid, precise, robust, nondestructive, and economical method to evaluate quality components is of major
interest to growers, processors, and breeders. NIR reflectance spectroscopy (NIRS) is routinely used for the prediction of
quality traits in many crops. This study was conducted to establish a rapid analytical method for determining the quality
of intact seeds of V. galamensis. A total of 114 Vernonia accessions were scanned to determine seed weight, FA composition, oil, and protein contents using NIRS. Conventional chemical
analysis for FA composition, total oil, and protein contents were performed by GC, Soxhlet extraction, and the Dumas combustion
method, respectively. Calibration equations were developed and tested through cross-validation. The coefficient of determination
in cross-validation for FA ranged from 0.47 (linoleic acid) to 0.55 (vernolic acid), and for oil, protein, and seed weight
from 0.71 (oil) to 0.86 (seed protein). It was concluded that NIRS calibration equations developed for seed weight and seed
quality traits can be satisfactorily used as early screening methods in V. galamensis breeding programs. 相似文献
85.
Michael Kuhn Christoph Kirse Heiko Briesen 《American Institute of Chemical Engineers》2018,64(1):68-76
Because there is no general design method for depth filters, especially for layered configurations, this methodological gap is addressed here. Using optimal control theory, paths of the filter coefficient, a measure for local filtration performance, are determined along the filter depth. An analytical optimal control solution is derived and used to validate the numerical algorithm. Two optimal control scenarios are solved numerically: In the first scenario, the goal of constant deposition along the filter depth is addressed. The second scenario aims at maximizing the time until some maximal pressure drop is reached. Furthermore, a computational strategy is presented to derive discrete layers suitable for practical design from the continuous optimal control solutions. All optimized scenarios are compared to one‐layered filter designs and significant improvements are found. As this work is based on strongly validated and widely used filtration models, the presented methods are expected to have broad applicability. © 2017 American Institute of Chemical Engineers AIChE J, 63: 68–76, 2018 相似文献
86.
Groundwater heads were mapped for the entire State of Mecklenburg-Western Pomerania by applying a Detrended Kriging method based on a numerical geohydraulic model. The general groundwater flow system (trend surface) was represented by a two-dimensional horizontal flow model. Thus deviations of observed groundwater heads from simulated groundwater heads are no longer subject to a regional trend and can be interpolated by means of Ordinary Kriging. Subsequently, the groundwater heads were obtained from the sum of the simulated trend surface and interpolated residuals. Furthermore, the described procedure allowed a plausibility check of observed groundwater heads by comparing them to results of the hydraulic model. If significant deviations were seen, the observation wells could be allocated to different aquifers. The final results are two hydraulically established groundwater head distributions – one for the regional main aquifer and one for the upper aquifer which may differ locally from the main aquifer. 相似文献
87.
Blickhan R Seyfarth A Geyer H Grimmer S Wagner H Günther M 《Philosophical transactions. Series A, Mathematical, physical, and engineering sciences》2007,365(1850):199-220
Research on the biomechanics of animal and human locomotion provides insight into basic principles of locomotion and respective implications for construction and control. Nearly elastic operation of the leg is necessary to reproduce the basic dynamics in walking and running. Elastic leg operation can be modelled with a spring-mass model. This model can be used as a template with respect to both gaits in the construction and control of legged machines. With respect to the segmented leg, the humanoid arrangement saves energy and ensures structural stability. With the quasi-elastic operation the leg inherits the property of self-stability, i.e. the ability to stabilize a system in the presence of disturbances without sensing the disturbance or its direct effects. Self-stability can be conserved in the presence of musculature with its crucial damping property. To ensure secure foothold visco-elastic suspended muscles serve as shock absorbers. Experiments with technically implemented leg models, which explore some of these principles, are promising. 相似文献
88.
Grimm S Schwirn K Göring P Knoll H Miclea PT Greiner A Wendorff JH Wehrspohn RB Gösele U Steinhart M 《Small (Weinheim an der Bergstrasse, Germany)》2007,3(6):993-1000
The fabrication of one-dimensional (1D) nanostructures and microstructures inside the pores of porous templates is intensively investigated. The release of these structures is commonly accomplished by etching and destroying the templates. The 1D nanostructures and microstructures tend to condense because of the occurrence of capillary forces during drying of the specimens. It is shown that highly ordered arrays of polymer microfibers can be easily detached from silanized porous templates by mechanical lift-off. This procedure leaves the templates intact, thus allowing their recycling, and does not involve the use of solutions or solvents, thus circumventing condensation. Therefore, mechanical lift-off may enable the up-scaling of template-based approaches to the fabrication of highly ordered assemblies of 1D nanostructures and microstructures. 相似文献
89.
90.
Heiko Kleykamp 《Journal of Nuclear Materials》1999,270(3):372-375
The enthalpy of γ-LiAlO2 was measured between 403 and 1673 K by isothermal drop calorimetry. The smoothed enthalpy curve between 298 and 1700 K results in H0(T) − H0(298 K)=−37 396 + 93.143 · T + 0.00557 · T2 + 2 725 221 · T−1 J/mol. The standard deviation is 2.2%. The heat capacity was derived by differentiation of the enthalpy curve. The value extrapolated to 298 K is Cp,298=(65.8 ± 2.0) J/K mol. 相似文献