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Die Vanadium Redox Flow Batterie (VRFB) hat ein großes Potenzial als kommerzielles elektrochemisches Energiespeichersystem eingesetzt zu werden, aufgrund von ausge-zeichneten Eigenschaften wie zum Beispiel einer langen Lebensdauer sowie einer theo-retisch unendlich hohen Kapazität. Die am meiste verwendete Membran in VRFB ist Nafion™ (DuPont), welche neben mehreren positiven Eigenschaften wie einer guten chemischen und mechanischen Stabilität auch eine sehr schlechte Ionenselektivität be-sitzt. Aufgrund dieser schlechten Ionenselektivität werden nicht nur Protonen, sondern auch Vanadium-Ionen durch die Nafion Membran transportiert. Die Folgen dieses Pro-zesses, auch Crossover genannt, sind in der Regel über mehrere Lade-Entlade-Zyklen eine Zunahme der Vanadium-Menge im Positiven Elektrolyten (PE), eine Volumenzu-nahme des PE, die Selbstentladung der Batterie sowie schlussendlich die Abnahme der Kapazität. Die genauen Transportprozesse von Vanadium-Ionen durch die Membran sind noch nicht verstanden. Dies wird unterstrichen durch die publizierten Diffusions-koeffizienten der Vanadium-Spezies. Zum Beispiel befinden sich die veröffentlichten Diffusionskoeffizienten von VII zwischen 3,13 · 10-12 m2s-1 und 9,44 · 10-12 m2s-1. Für ein besseres Verständnis der Transportvorgänge in der Membran einer VRFB, fokussiert sich unsere Arbeit auf die Entwicklung neuer Prozeduren für die Elementbestimmung und Speziation von Vanadium in VRFB mittels Photometrie und Labor-Röntgen-Nah-kanten-Absorptions-Spektroskopie (XANES). In der folgenden Arbeit wird gezeigt, dass Nafion™ 117 bei 18 °C 22,89 ± 0,58 % Wasser aufnimmt und nach einer Konditi-onierung in einem Vanadium-Elektrolyten die wässrige Phase des Nafion™ eine Vana-dium-Konzentration von 1,029 ± 0,024 mol kg-1 aufweist. Der Gehalt auf die hydrierte Membran bezogen beträgt 0,192 ± 0,004 mol kg-1, welcher λ = n(V)/n(SO3) = 0,211 ± 0,005 entspricht. Zusätzlich wird gezeigt, dass sich sowohl die Photometrie als auch die Labor-XANES zur direkten Speziation von Vanadium in Nafion™ eignen.

Updating a knowledge base to remove an unwanted consequence is a challenging task. Some of the original sentences must be either deleted or weakened in such a way that the sentence to be removed is no longer entailed by the resulting set. On the other hand, it is desirable that the existing knowledge be preserved as much as possible, minimising the loss of information. Several approaches to this problem can be found in the literature. In particular, when the knowledge is represented by an ontology, two different families of frameworks have been developed in the literature in the past decades with numerous ideas in common but with little interaction between the communities: applications of AGM-like Belief Change and justification-based Ontology Repair. In this paper, we investigate the relationship between pseudo-contraction operations and gentle repairs. Both aim to avoid the complete deletion of sentences when replacing them with weaker versions is enough to prevent the entailment of the unwanted formula. We show the correspondence between concepts on both sides and investigate under which conditions they are equivalent. Furthermore, we propose a unified notation for the two approaches, which might contribute to the integration of the two areas.

36th European Photovoltaic Solar Energy Conference and Exhibition; 1134-1137, El-images are used to visualize defects in solar modules. Quantitative and comparable figures to address and identify defective cells are not extracted from the images so far. We used a statistical approach to get three key figures from the images: defective status, power-relevant area, and cell degradation. For analysis several EL-images of the same module were necessary. To study the impact of wind loads on the crack structures, the modules were exposed to 23,300 mechanical loading cycles, mimicking wind loads up to 40 m/s. The evolution of the crack structures was studied based on the ELimages that were recorded occasionally. The image evaluation reveals that defective, power-reducing cells and nondefective cells can be distinguished. Cell changes could be identified. The impact on the module power was within the measurement accuracy.

36th European Photovoltaic Solar Energy Conference and Exhibition; 854-859, EL-images nicely visualize the cell quality of PV-modules in terms of existing failures like cell cracks and cell fractures. Nonetheless, the benefit of EL-images recorded in the field increases if a direct prediction of the module power is enabled. For the first time, deep learning algorithms are applied to predict the module power using EL-images. The dataset consists of more than 600 EL-images from different crystalline PV module manufactures. Regarding the network architecture, ResNet18 was identified to perform best with respect to computational time and accuracy. The predicted powers are quite accurate: the mean absolute error over the entire data set is 4.57 W. In addition, 72% of the module powers are predicted with a high accuracy of less than 2% error. Finally, it should be emphasized that even the EL-images recorded in the field with perspective distortion and motion blur are suitable for excellent predictions.

We study the following question: if τ is a TBox that is formulated in an expressive DL L and all CQs can be evaluated in PTime w.r.t. τ, can τ be replaced by a TBox τ' that is formulated in the Horn-fragment of L and such that for all CQs and ABoxes, the answers w.r.t. τ and τ' coincide? Our main results are that this is indeed the case when L is the set of ALCHI or ALCIF TBoxes of quantifier depth 1 (which covers the majority of such TBoxes), but not for ALCHIF and ALCQ TBoxes of depth 1.

35th European Photovoltaic Solar Energy Conference and Exhibition; 1287-1289, In this paper a dataset consisting of 2,426 solar cells extracted from high-resolution electroluminescence (EL) images is used for automated defect probability recognition. The collected images contain both functional and defective solar cells with varying degrees of degradation both in monocrystalline and polycrystalline solar modules. The images were labeled by expert who categorized the solar cells by the likelihood of a defect within each image. The labeled images can be used for development of computer vision and machine learning methods for automatic detection of different defects, like cracks, fracture interconnects, PID, and cell quality and for the purpose of predicting the power efficiency loss.

Der Sammelband beinhaltet drei zentrale Kernrahmen: soziale Sicherung im Umbruch respektive soziale Herausforderungen unserer Zeit in Verbindung mit transdisziplinaren Ansatzen. Die Einfuhrung zum Sammelband spricht eingangs kurz an, um welche Phanomene es sich handelt und welche Schnittmengen zueinander bestehen. Ferner geht es um den Stellenwert der drei Aspekte in der Gesamtschau auf den Sammelband. In einem weiteren Part der Einfuhrung werden die Beitrage zu den einzelnen Kapiteln anmoderiert.

Der Beitrag zeigt zunachst auf, welche allgemeinen Gegenstandsbereiche und Ambivalenzen gesellschaftliche Partizipation im Sinne von Bildung und sozialer Teilhabe innehat. Das Bildungs- und Teilhabepaket (BuT) kann vor diesem Hintergrund im Prinzip als innovativ bezeichnet werden, da es das Ziel der sozialen Inklusion von Kindern, Jugendlichen und jungen Erwachsenen in besonderen und u. U. prekaren Lebenslagen verfolgt, in denen ‚Bildungsarmut‘ sowie soziale Isolation drohen konnen. Neben einer Beschreibung der Entstehungsgeschichte und der Instrumente des BuT wirft der Beitrag einen Blick auf die Erfahrungen bei der Ein- und Weiterfuhrung des BuT. Vor diesem Hintergrund zeigt der Artikel auch die Schwierigkeiten beim Absatz dieser Leistungen auf. Schlussendlich wird der Fokus auf ein adaquates Public Marketing der BuT-Leistungen gelegt, um entsprechende Modifikationen und Alternativen vorzustellen.

35th European Photovoltaic Solar Energy Conference and Exhibition; 1554-1558, PV-modules with precracked solar cells are frequently present in PV-plants as current inspection methods reveal. How these modules perform in the future is still unknown. Uniform static loading tests characterize short-term performance well, as presented previously (EUPVSEC 2017). In order to simulate long-term stability, the application of alternating loads, comparable to wind gusts, is important. The load cycle is fed into the improved mechanical loading test-setup by a PLC whilst recording EL-images simultaneously and measuring IV-curves. For the first time, module performance for long-term stability with 100,000 cycles are presented. The results show that with an increasing number of cycles and pressure, the EL-intensity distribution of cracked cells changes but the performance loss is rather small. These findings correlate with analysis of field-exposed modules.

Der Beitrag fuhrt zunachst in den Begriff und die Definition von Public Marketing in Abgrenzung und im Vergleich zu Paradigmen aus den Diskursen um ‚Burgernahe‘, ‚New Public Management‘ und ‚Governance‘ ein. Public Marketing kann dabei als Oberbegriff fur samtliche zweckgerichtete Aktivitaten zur Vermarktung des Staatswesens (‚Primares Public Marketing‘) sowie als Marketing von offentlichen Geld-, Sach- und Dienstleistungen (‚Sekundares Public Marketing‘) bezeichnet werden. Die Notwendigkeit von Public Marketing ergibt sich aus der Immaterialitat des Staatsgebildes und der offentlichen Dienstleistungen sowie aus der Angebotsmonopolstellung des Staates. Auf die Standortbestimmung folgend wird der Public Marketing-Managementprozess beschrieben und Public Marketing auf den Bereich der sozialen Sicherung ubertragen. Es wird aufgezeigt, dass ein erhebliches noch brach liegendes Potential bei Public Marketing insbesondere nicht zuletzt auch fur solche soziale Leistungen besteht, welche kein hohes offentliches Ansehen innehaben. Mit einem entsprechenden Marketing the ‚Ugly‘ kann mitunter das schlechte Image der betreffenden Leistungen verbessert und eine damit potentiell einhergehende Stigmatisierung der Leistungsempfanger abgemildert werden

35th European Photovoltaic Solar Energy Conference and Exhibition; 2001-2004, Potential induced degradation (PID) is still a severe problem in many PV-installations and a huge financial risk for investors and plant-owners if not detected early. In previous investigations it was shown that thermography, conducted with handheld or drone mounted IR-cameras, is a fast and reliable tool to detect PID affected PV-modules on site and estimate their remaining electrical power during normal plant operation. In this work we show how to improve the sensitivity of IR- and various other imaging techniques by using the characteristic behavior of PID affected cells regarding the different excitation forces, i.e. solar irradiance for IR- and electric current for DLIT- and EL-measurements. Furthermore, we address the implications of this specific behavior by simulating the energy yield of several PID affected PV-strings based on real monitoring data for two inspected sites and suggest carrying out the measurements on site- and under failure- relevant conditions rather than standard test conditions.

We study the approximation of expressive Horn DL ontologies in less expressive Horn DLs, with completeness guarantees. Cases of interest include Horn-SRIF-to-ELR⊥, Horn-SHIF-to-ELH⊥, and others. Since finite approximations almost never exist, we carefully map out the structure of infinite approximations. This provides a solid theoretical foundation for constructing incomplete approximations in practice in a controlled way. Technically, we exibit a connection to the axiomatization of quasi-equations valid in classes of semilattices with operators and additionally develop a direct proof strategy based on the chase and on homomorphisms that allows us to also deal with approximations of bounded role depth.

35th European Photovoltaic Solar Energy Conference and Exhibition; 1147-1151, EL-imaging is a valuable tool to analyze PV-modules for the presence of cracked cells. Normally, these inspections are done in air-conditioned labs or at cool nights outdoors. However, the PV-modules are supposed to generate energy outdoors in the field. Therefore, they operate at significantly elevated temperatures which are much higher than the temperatures at the inspection time. In order to investigate the temperature influence on the performance of precracked PV-modules, EL-images and IV-curves were recorded of warm and mechanically loaded modules. The study illustrates that the performance of cracked cells changes with temperature and pressure. There is the tendency that modules at elevated temperatures perform better than those at low temperatures under the same loading situation.

Der Beitrag zeigt eingangs auf, inwieweit Transdisziplinaritat in Abgrenzung sowie mit Schnittmengen zur Multi- und Interdisziplinaritat beschrieben werden kann. Ferner werden die Gegenstandsbereiche der Multi-, Inter- und Transdisziplinaritat aufgezeigt. Ein weiterer Part des Beitrags legt den Fokus auf die Nutzung von transdisziplinaren Ansatzen im Segment der sozialen Sicherung. Es wird aufgezeigt, welchen Mehrwert transdisziplinare Perspektiven fur die Planung und Umsetzung von sozialer Sicherung haben und welche Grenzen ausgemacht werden konnen.

Mit einem Blick auf die Beschaftigungssituation in den Mitgliedsstaaten der Europaischen Union glanzt Deutschland derzeit mit Erfolgsmeldungen. Die relativ gute Performanz des deutschen Arbeitsmarktes ist einerseits gerechtfertigt, so etwa im Vergleich zu sudeuropaischen Staaten. Auf der anderen Seite gilt es fur Deutschland zu hinterfragen, ob und inwiefern sich der hiesige Arbeitsmarkt nachhaltig und damit zukunftsfest entwickelt. Der Beitrag geht in erster Linie auf Einkommensaspekte, aber auch auf soziale Ungleichheit in der Verteilung von Beschaftigung und Einkommen ein. Kennziffern, wie die Quote der relativen Einkommensarmut oder die Arbeitslosenquote werden allgemein oft mit Bezugen zur sozialen Ungleichheit dargestellt. Selten finden sich jedoch Debatten, welche in die entgegengesetzte Richtung argumentieren und soziale Ungleichheit als Mitursache fur eine suboptimale Performanz einer Volkswirtschaft ansehen, so beispielsweise in Bezug auf das Wirtschaftswachstum oder mit Blick auf die Lebenszufriedenheit einer Gesellschaft. Auch diese Perspektive soll der Beitrag ansprechen, um die Nachhaltigkeit von Beschaftigungsmustern auch jenseits von sozialer Gerechtigkeit bewerten zu konnen.

33rd European Photovoltaic Solar Energy Conference and Exhibition; 1931-1936, Potential induced degradation (PID) causes severe damage and financial losses even in modern PVinstallations. In Germany, approximately 19% of PV-installations suffer from PID and resulting power loss. This paper focuses on the impact of PID in real installations. The analysis focuses exemplarily on a 314 kWp PV-system in the Atlantic coastal climate. Infrared (IR)-imaging is used for identifying PID without operation interruption. Historic electric performance monitoring data for several years are analyzed on system and string level. Additionally, punctually measured module string current-voltage (I-V)-curves are considered. The data sets are combined for understanding the PID behavior of this PV plant. The number of PID affected cells within a string varies strongly between 1 to 22% with the string position on the building complex. A PID-resistance which correlates to the defined PID-defect-ration is presented. Finally, indicators for the reliable determination of PID is given.

33rd European Photovoltaic Solar Energy Conference and Exhibition; 2320-2324, First statistical evaluation of IR-inspections of PV-plants reveals that 81% of the installed PV-plants show IR-abnormalities. More than 140 PV-plants with more than 200,000 PV-modules were inspected and evaluated statistically. Main IR-abnormalities or failures in modules and string installations are analyzed, respectively. The average failure rate for PV-modules is about 6% and for module strings approximately 1%. The differentiation based on the installation type reveals that small residential installations relatively seen show more defective modules than large field installations. A first estimation of the missed income by not detecting and maintaining major module and plant failures yield a missed income of about 100 Mio. EUR considering the PV-systems installed in Germany. IR-imaging is a valuable method to give fast and reliable information about the actual quality and failure rate in inspected PV-installations.

Mineral coronas and reaction rims are frequent features in manymetamorphic rocks commonly interpreted as having been controlled by solid-state diffusion or by diffusion in an undefined medium. In material science the term ‘interlayer growth’ is often used for such processes. However, the terms ‘reaction bands’, ‘corona structures’, or ‘rim structures’ are commonly used as descriptive terms in petrology and we will use these below. The formation of reaction bands, coronas and reaction rims between incompatible phases requires that one or more chemical components are mobile. Knowledge of the transport mechanism and relative mobility of the distinct chemical components is of prime interest for the interpretation of reaction band sequences, growth rates, and subsequently forming fabrics and textures. Recent experimentation at high pressures and temperatures has shown that even minute traces of water are decisive in changing reaction mechanisms in silicate systems. In this chapter we present avenues of experimentation classified as water-rich, waterpoor and water-absent. All of them are important in order to gain deeper understanding of mineral-reaction kinetics in the Earth in different environments, and of the formation of texture and zoning patterns in rock assemblages of the Earth or Earth-like planets. Experimental simulation and parameterization of variables relevant for mineralreaction kinetics and the development of microstructures and textures requires a specific experimental approach. This consists of (1) application of time (or temperature) series; (2) miniaturization of experimental setups; and (3) experiments with perfectly defined geometries of the phases involved. This chapter specifies experimental setups for investigating mineral-reaction kinetics at high P-T, including setups for time-resolved, real-time monitoring of mineral nucleation and growth between incompatible phases at high T. We address mainly the experimental strategies in elucidating the controls of mineral-reaction kinetics rather than responding to results of particular studies, which can be found in many other chapters in this volume and in previous review articles (e.g. Dohmen and Milke, 2010; Watson and Dohmen, 2010). This holds also for the applied analytical methods as many experimental setups are specifically designed for subsequent analytical procedures.

33rd European Photovoltaic Solar Energy Conference and Exhibition; 1451-1456, Damaged modules, especially with existing cell cracks, are observed quite often in PV-installations. Little knowledge exists about the stability of such pre-cracked modules under real operating conditions. Previous investigations and existing standards focus on the degradation of new, defect-free modules. This work highlights a twofold approach for performance study of pre-cracked modules: 1) artificial stressing of 20 representative pre-cracked modules with a novel load test set-up simulating snow and wind loads, 2) simulating IV-curves of cracked cells. The experimental results are discussed with respect to field exposure data. EL-images of stressed PV-modules indicate that new cracks are only initiated once a certain threshold is exceeded. Below this threshold formerly unseen cracks open, as can be seen by small changes in the EL-intensity. Power measurements yield a strong power reduction at the loaded state. Due to the solar cell being under tension the cracks open and the separated areas lose their electrical contact. Considering a break resistance in the IVcurve, simulations lead to good agreement with the observed experimental results. It is highlighted that the electric contact after unloading for the previously unloaded module recovers visibly in the ELimage as well as in the power output. Simulating real weather (operating) conditions by moderate static loading tests reveals no measurable changes in the EL-images affecting the power output.

33rd European Photovoltaic Solar Energy Conference and Exhibition; 2274-2279, In this paper, a new metric for assessing the location-specific mechanical loads imposed by snow or wind gusts which a photovoltaic module can be expected to be exposed to at a given location is introduced. For demonstrating this general approach, two locations of moderate distance (~110km) in Northern Bavaria are compared. It is shown that even on moderate distances the expected loads differ by a factor of four or more highlighting the importance of location-specific requirements for PV modules. For assessing the loads, the historical weather data of the closest surrounding weather station is evaluated in order to deduce an expectation value for the site of interest. This data is analyzed with respect to the frequency and severity of the relevant weather events such that the annuality of a weather event of a given severity can be determined. Finally, the severity of an event corresponding to a single occurrence in 20 years, i.e. a standard product warranty, is chosen to represent the requirements of a location with respect to a certain parameter.