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Automatic Identification of Travel Locations in Rare Books - Object Oriented Information Management
(2017)
The digital content of the Internet is growing exponentially and mass digitization of printed media opens access to literature, in particular the genre of travel literature from the 18th and 19th century, which consists of diaries or travel books describing routes, observations or inspirations. The identification of described locations in the digital text is a long-standing challenge which requires information technology to supply dynamic links to sources by new forms of interaction and synthesis between humanistic texts and scientific observations.
Using object oriented information technology, a prototype of a software tool is developed which makes it possible to automatically identify geographic locations and travel routes mentioned in rare books. The information objects contain properties such as names and classification codes for populated places, streams, mountains and regions. Together, with the latitudes and longitudes of every single location, it is possible to geo-reference this information in order that all processed and filtered datasets can be displayed by a map application. This method has already been used in the Humboldt Digital Library to present Alexander von Humboldt’s maps and was tested in a case study to prove the correctness and reliability of the automatic identification of locations based on the work of Alexander von Humboldt and Johann Wolfgang von Goethe.
The results reveal numerous errors due to misspellings, change of location names, equality of terms and location names. But on the other hand it becomes very clear that results of the automatic object detection and recognition can be improved by error-free and comprehensive sources. As a result an increase in quality and usability of the service can be expected, accompanied by more options to detect unknown locations in the descriptions of rare books.
Micro gas turbines (MGTs) are regarded as combined heat and power (CHP) units which offer high fuel utilization and low emissions. They are applied in decentralized energy neration.
To facilitate the planning process of energy systems, namely in the context of the increasing application of optimization techniques, there is a need for easy-to-parametrize component models with sufficient accuracy which allow a fast computation. In this paper, a model is proposed where the non-linear part load characteristics of the MGT are linearized by means of physical insight of the working principles of turbomachinery. Further, it is shown that the model can be parametrized by the data usually available in spec sheets. With this model a uniform description of MGTs from several manufacturers
covering an electrical power range from 30kW to 333kW can be obtained. The MGT model was
implemented by means of Modelica/Dymola. The resulting MGT system model, comprising further heat exchangers and hydraulic components, was validated using the experimental data of a 65kW MGT from a trigeneration energy system.
Polygeneration systems are a key technology for the reduction of primary energy usage and emissions. High costs, lack of flexibility and effort for parameterization hinder the wide usage of modeling tools during their conceptual design. This paper describes how planning tools can be structured for the conceptual design phase where only little information is available to the planner. A library concept was developed using the principles of object-oriented modeling to address the flexibility issue. With respect to cost and expandability, the open-source modeling language Modelica was chosen. Furthermore, easy-to-parameterize component models were developed. In addition to the improved library concept and novel component models, an easy-to-adapt control concept is proposed. The component models were validated and the applicability of the library was demonstrated by means of an example. It was shown that the data usually obtained from spec sheets are sufficient to parameterize the models. In addition to this, the control concept was approved.
A complete thermomechanical fatigue (TMF) life prediction methodology is developed for predicting the TMF life of cast iron cylinder heads for efficient heavy duty internal combustion engines. The methodology uses transient temperature fields as thermal loads for the non-linear structural finite-element analysis (FEA). To obtain reliable stress and strain histories in the FEA for cast iron materials, a time and temperature dependent plasticity model which accounts for viscous effects, non-linear kinematic hardening and tensioncompression asymmetry is required. For this purpose a unified elasto-viscoplastic Chaboche model coupled with damage is developed and implemented as a user material model (USERMAT) in the general purpose FEA program ANSYS. In addition, the mechanismbased DTMF model for TMF life prediction developed in Part I of the paper is extended to three-dimensional stress states under transient non-proportional loading conditions. The material properties of the plasticity model are determined for lamellar graphite cast iron GJL250 and vermicular graphite cast iron GJV450 from isothermal and non-isothermal uniaxial tests. The methodology is applied to obtain a TMF life prediction on two cast iron cylinder heads for heavy duty diesel engine applications made from both cast iron materials. It is shown that the life predictions using the developed methodology correlate very well with observed lives from two bench tests in terms of location as well as number of cycles to failure.
The DMFC is a promising option for backup power systems and for the power supply of portable devices. However, from the modeling point of view liquid-feed DMFC are challenging systems due to the complex electrochemistry, the inherent two-phase transport and the effect of methanol crossover. In this paper we present a physical 1D cell model to describe the relevant processes for DMFC performance ranging from electrochemistry on the surface of the catalyst up to transport on the cell level. A two-phase flow model is implemented describing the transport in gas diffusion layer and catalyst layer at the anode side. Electrochemistry is described by elementary steps for the reactions occurring at anode and cathode, including adsorbed intermediate species on the platinum and ruthenium surfaces. Furthermore, a detailed membrane model including methanol crossover is employed. The model is validated using polarization curves, methanol crossover measurements and impedance spectra. It permits to analyze both steady-state and transient behavior with a high level of predictive capabilities. Steady-state simulations are used to investigate the open circuit voltage as well as the overpotentials of anode, cathode and electrolyte. Finally, the transient behavior after current interruption is studied in detail.
Warmumformwerkzeuge unterliegen während des Betriebes komplexen thermischen und mechanischen Beanspruchungen. In kritischen Bereichen können dadurch lokal Spannungen entstehen, die die Fließgrenze überschreiten. Bei der Serienproduktion führt dies zu zyklischen plastischen Verformungen und zur thermomechanischen Ermüdung, welche die Lebensdauer der Warmumformwerkzeuge maßgeblich bestimmen kann. Zur Bewertung der thermomechanischen Ermüdung der Warmumformwerkzeuge gibt es jedoch heute keine etablierten Konzepte, da dieser Aspekt erst durch die Notwendigkeit einer höheren Ressourcen- und Energieeffizienz und optimierter Produktionsprozesse (beispielsweise im Rahmen von Industrie 4.0) eine höhere Aufmerksamkeit erreicht. In dieser Arbeit wird zum einen die aktuell industriell angewandte Vorgehensweise zur Auslegung von Warmumformwerkzeugen hinsichtlich der Lebensdauer erläutert. Des Weiteren wird ein Überblick über existierende Plastizitätsmodelle und Lebensdauermodelle gegeben. Dabei wird zwischen rein phänomenologischen und mechanismenbasierten Modellen unterschieden. Aus der betriebenen Recherche wird ersichtlich, dass weiterer Forschungsbedarf auf diesem Gebiet notwendig ist.
In diesem Beitrag werden die Bereitstellungskosten flexibler Systemkomponenten im deutschen Stromsystem analysiert, zu deren Quantifizierung eine einheitliche Methodik entwickelt wird. Dabei ist das Ziel des Beitrags, zeitlich differenzierte Kostenpotenzialkurven für die Jahre 2015 und 2030 zu erarbeiten, anhand derer die energiespezifischen Kosten der markt- und systemdienlichen Flexibilitätsbereitstellung verglichen und die einzelnen Flexibilitätsoptionen in einen Gesamtkontext eingeordnet werden können.
Der Einsatz flexibler Systemkomponenten wird hierzu in die drei Hauptphasen (1) Vorhaltung, (2) Abruf und (3) Einsatzfolgen unterteilt, woraus sich drei kongruente Kostengruppen ableiten lassen, nach denen die einzelnen Kostenbestandteile identifiziert und als Ergebnis die Bereitstellungskosten quantifiziert werden. Neben fossil-thermischen Kraftwerken werden dabei bspw. die Kraft-Wärme-Kopplung, Biogasanlagen, Pumpspeicher- und Laufwasserkraftwerke sowie steuerbare Lasten untersucht.
Zur anschließenden Abbildung der teils negativen Bereitstellungskosten wird die herkömmliche Darstellungsform der Merit Order entlang der Ordinate um die Abbildung negative Werte erweitert und die Abszisse für die Abbildung negativer Flexibilität in umgekehrter Reihenfolge angeordnet. Das Ergebnis sind zwei zusammenhängende Graphen, mittels derer sich die Bereitstellungskosten verschiedener Flexibilitätsoptionen gegenüberstellen und anschaulich vergleichen lassen.
Durch die Festlegung eines Rahmenszenarios zur Entwicklung des deutschen Stromsystems bis zum Jahr 2030 wird anschließend auch die zukünftige Perspektive der Flexibilitätsbereitstellung in Deutschland analysiert. Aus den Ergebnissen lässt sich ableiten, dass der deutsche Kraftwerkspark mit einem fortschreitenden Rückbau der Kohlekraftwerke nur dann zunehmend flexibler wird und auf höhere Schwankungen im Stromnetz reagieren kann, wenn von einem gleichzeitigen Zubau moderner erdgasbetriebener Kraftwerke ausgegangen wird. In diesem Fall steigen die Bereitstellungskosten positiver Flexibilität, was sich beispielsweise durch zukünftig steigende Brennstoffpreise bergründen lässt. Jedoch kann bspw. durch die Transformation der Kraft-Wärme-Kopplung hin zu einer grundsätzlich stromgeführten Fahrweise zukünftig eine vergleichsweise kostengünstige Flexibilitätsbereitstellung erschlossen und somit auch ein gleichbleibendes oder oftmals sogar höheres Flexibilitätsniveau am Markt erreicht werden.
We present a two-dimensional (2D) planar chromatographic separation method for phytoestrogenic active compounds on RP-18 W (Merck, 1.14296) phase. It could be shown that an ethanolic extract of liquorice (Glycyrrhiza glabra) roots contains four phytoestrogenic active compounds. As solvent, in the first direction, the mix of hexane, ethyl acetate, and acetone (45:15:10, v/v) was used, and, in the second direction, that of acetone and water (15:10, v/v) was used. After separation, a modified yeast estrogen screen (YES) test was applied, using the yeast strain Saccharomyces cerevisiae BJ3505. The test strain (according to McDonnell) contains the estrogen receptor. Its activation by estrogen active compounds is measured by inducing the reporter gene lacZ which encodes the enzyme β-galactosidase. This enzyme activity is determined on plate by using the fluorescent substrate MUG (4-methylumbelliferyl-β-d-galactopyranoside). The enzyme can also hydrolyse X-β-Gal (5-bromo-4-chloro-3-indoxyl-β-d-galactopyranosid) into β-galactose and 5-bromo-4-chloro-3-indoxyl. The indoxyl compound is oxidized by oxygen forming the deep-blue dye 5,5β-dibromo-4,4β-dichloro-indigo which allows to detect phytoestrogenic activity more specific in the presence of native fluorescing compounds.