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Relying on a recent survey of more than 3300 participants from China, Germany and the US, this paper empirically analyzes citizens’ perceptions of climate change and climate policy, focusing on key guiding principles for sharing mitigation costs across countries. The ranking of the main principles for burden-sharing is identical in China, Germany and the US: accountability followed by capability, egalitarianism, and sover-eignty. Thus, on a general level, citizens across these countries seem to have a com-mon understanding of fairness. We therefore find no evidence that citizens’ (stated) fairness preferences are detrimental to future burden-sharing agreements. While there is heterogeneity in citizens’ perceptions of climate change and climate policy within and across countries, a substantial portion of citizens in all countries perceive a lack of transparency, fairness, and trust in international climate agreements.

Indigene Kulturen stehen in einheitlicher Verbindung mit der Natur, betrachten diese weder als kulturellen Gegensatz noch den Menschen als von der Umwelt getrennt. Die Begriffe nuna und sila beispielsweise und die Gestalt der Sedna, die dem traditionellen Denken der Inuit zugrunde liegen, marginalisieren die Rolle des Menschen in seiner Lebenswelt. 2009 veröffentlicht die grönländische Autorin Lana Hansen eine »Erzählung über den Klimawandel«, Sila . Sie plädiert darin für eine ganzheitliche Sichtweise und verwendet Konzepte, die Menschen, Tiere, Sprachen, Geister, Erinnerungen, Pflanzen und Ressourcen einbeziehen. Dieser Artikel kontextualisiert Hansens Erzählung aus Sicht der grönländischen und der Inuit-Literatur und untersucht die mit eingebrachten traditionellen Quellen. Indigenous cultures have an integrated relationship with nature, and do not view it in opposition to culture, nor do they consider humans as separate from the environment. For example, the concepts of nuna and sila and the figure of Sedna, at the basis of the traditional Inuit thought, decenter the role of humans in the living world. In 2009, Greenlandic author Lana Hansen published a »tale about climate change«, Sila . She calls for a holistic view, using concepts that encompass humans, animals, languages, spirits, memories, plants, and resources. This article aims to review the context of publication of Hansen’s tale from a point of view of Greenlandic and Inuit literature and to examine the traditional sources that it brings into play.

A dedicated sample of Large Hadron Collider proton-proton collision data at centre-of-mass energy $\sqrt{s}=8$ TeV is used to study inclusive single diffractive dissociation, $pp \rightarrow Xp$. The intact final-state proton is reconstructed in the ATLAS ALFA forward spectrometer, while charged particles from the dissociated system $X$ are measured in the central detector components. Cross sections are measured differentially as functions of the proton fractional energy loss $\xi$, the squared four-momentum transfer $t$, and $\Delta \eta$, a variable that characterises the rapidity gap separating the proton and the system $X$. The data are consistent with an exponential $t$ dependence, ${\rm d} \sigma / {\rm d} t \propto \text{e}^{Bt}$ with slope parameter $B = 7.65 \pm 0.34 \ {\rm GeV^{-2}}$. Interpreted in the framework of Regge phenomenology, the $\xi$ dependence leads to a pomeron intercept of $\alpha(0) = 1.07 \pm 0.09$.

Solar energy has the potential to provide clean and sustainable energy to all of humankind and during the past years the amount of operating solar power plants constantly increased. The increasing installation and production volumes call for powerful measuring techniques for the process control of solar cell production lines, but also for the monitoring of modules operating in solar power plants. Luminescence imaging of solar cells and modules is such a measuring technique. By observing the radiative recombination that is emitted by a solar cell, just like the light emission of LEDs, luminescence imaging provides spatially resolved information about a solar cells electrical and optical properties. Therefore, luminescence imaging has the ability to locate and rate defects and inhomogeneities in solar cells. This thesis focuses on the use of luminescence imaging for quantitative evaluations. Hence, it is not only looked at the ability of luminescence imaging to locate abnormalities in solar cells or modules but also on possibilities to use luminescence imaging as a way to quantify the strength of a defect or to estimate the influence of a defect on the photovoltaic performance of a whole device. During this work it was made use of two model solar cell technologies. Crystalline silicon solar cells are currently the most successful solar cell technology for which luminescence imaging is already a well established tool. This technology is primarily used in this thesis to test newly developed imaging methods. However, the focus of this thesis lies on the analysis of the so called CIGS solar cells and modules, which belong to the thin-film technologies. Although the market share of the thin-film technologies was only 5 % of the produced solar cells in 2016 their production volumes are constantly increasing. To allow for a quantitative evaluation of luminescence images of CIGS solar cells it is first essential to understand the influence of metastable effects in this technology. Metastable effects alter the properties of CIGS solar cells, including the luminescence signal, during the exciation with illumination or the application of bias. An in depth analysis of the metastable effects at different applied currents and temperatures showed that the metastable effects lead in most cases to a reduction of the series resistance and dark recombination current in CIGS solar cells. The changes vary in magnitude for the different conditions and may happen within a matter of seconds. However, a stabilization of the solar cells can only be reached after a constant excitation of several hours. This knowledge is essential for an accurate quantitative evaluation of luminescence images. In this work, an influence of metastable effects on the results were avoided by automation and combining image data only with electrical data measured simultaneously. In the following a quantitative luminescence method is analyzed in detail that allows to determine the current/junction voltage characteristic of individual cells already connected within a module. The characteristics allow in turn the quantification of defects, like shunts, in the individual cells. The current/junction voltage characteristics obtained by imaging unexpectedly vary depending upon the illumination conditions at which they are measured. The difference is explainable by an error resulting from an averaging procedure of measured local junction voltages. This procedure does not yield an accurate measure for the voltage over a cell. As a second quantitative evaluation method, the so called photocurrent collection efficiency imaging method is analyzed. The method yields spatially resolved information about the ability of a solar cells to collect photocurrent and was experimentally demonstrated and verified on a crystalline silicon solar cell. The influence of parameters, like series resistances and shunts, on the photocurrent collection efficiency is extensively discussed and demonstrated with the help of simulations. Furthermore, the original method, which only yielded differential information is extended to allow a determination of the total amount of photocurrent collected from a certain area of a solar cell. This total photocurrent collection efficiency is closer related to the actual influence a certain area has on the performance of a solar cell. The new method was also verified experimentally with a crystalline silicon solar cell. On solar modules the photocurrent collection efficiency behaves different to single cells due to the series connection of cells. For example, defected cells may show a larger photocurrent collection efficency. The effects are demonstrated with CIGS mini-modules and explained using simulations. At low voltages the photocurrent collection efficiency imaging could not be verified for CIGS solar cells. It is shown that CIGS solar cells exhibit an injection dependent series resistance that increases at low voltages. This injection dependent series resistance could also be reproduced in device simulations and is resulting from the minority charge carrier transport through the CIGS absorber. An equivalent circuit model including an injection dependent series resistance is in the following used to explain the observed deviations in the photocurrent collection efficiency imaging of CIGS solar cells. Finally, it is discussed how this model could also be interesting to describe voltage dependent photocurrent that is often observed in many kinds of new solar cells technologies.

Stopping and accelerating at traffic lights is one of the main contributing factors to vehicular emissions in urban environments. The work in this paper demonstrates a generic guideline for minimizing CO2 emissions at traffic lights. This was done using an adaptive control, which uses a cost function for optimization, rather than network-specific control parameters. A new version of the emission model PHEMlight was used, which added of a fuel cut-off mode during coasting and other improvements compared to the previous version. Using this model, it could be determined that the emission optimal ratio between delay time and stops for the cost function of an adaptive control should be 1:4.8. Using this ratio a reduction of 7.6 % of CO2 emissions was achieved compared to a vehicle actuated control.

Im Zusammenhang mit der Energiewende sind große Mengen an Speicherkapazität erforderlich, um die stark fluktuierende Energieerzeugung durch Wind- und Solarkraftwerke zu integrieren. Die Umwandlung von elektrischer Energie in chemische Energie in der Form von Wasserstoff ist eine der technischen Möglichkeiten. Die Technologie der Untergrundwasserstoffspeicherung, wobei Wasserstoff in unterirdischen Gesteinsformationen, ähnlich wie bei der Speicherung von Erdgas, gespeichert wird, ist derzeit ein Forschungsschwerpunkt mehrerer europäischer Länder. Wasserstoff hat eine sehr geringe Dichte und Viskosität. Folglich wird eine hohe Tendenz für eine instabile Verdängung erwartet, einschließlich einer gravitationsbedingten Segregation und der Bildung von viskosen Fingern. Zusätzlich können biochemische Reaktionen eine wichtige Rolle in Untergrundwasserstoffspeichern spielen. Die Tatsache, dass Wasserstoff ein geeignetes Substrat für viele anaerobe mikrobielle Spezies ist, regt ihr Wachstum an und führt zu einer Umsetzung des Wasserstoffs. Insbesondere kann die Aktivität von methanogenen Archaeen zu drastischen Veränderungen in der Zusammensetzung des Gases führen, wie es bei einigen ehemaligen Stadtgasspeichern beobachtet wurde. Um das hydrodynamische und biochemische Verhalten in Untergrundwasserstoffspeichern zu untersuchen, wurden unterschiedliche analytische und numerische Methoden angewandt. Die schwerkraftgetriebene Verdrängung, wenn Wasserstoff am Boden einer wassergesättigten Lagerstätte injiziert wird, wurde analytisch modelliert. Die analytische Lösung ist durch Kombination der Methode der Charakteristiken und einer grafischen Konstruktion hergeleitet worden. Die exakte Aufstiegsgeschwindigkeit wurde für verschiedene geschichtete Lagerstätten und für Fluidphasen aus zwei und drei Komponenten bestimmt. Vergleiche mit der numerischen Lösung werden ebenfalls gezeigt. Daüber hinaus wurde ein mathematisches Modell für den bioreaktiven Transport in Untergrundwasserstoffspeichern entwickelt. Das Modell ist auf der Kontinuumsskala formuliert und koppelt die Mehrkomponenten-Zweiphasenströmung mit mikrobiellem Wachstum und biochemischen Reaktionen innerhalb des porösen Mediums. Die Stabilität des mathematischen Modells ist untersucht worden, indem es auf ein Paar von Differentialgleichungen reduziert wurde. Basierend auf den Ergebnissen wurden numerische Simulationen unter Grenzzyklus und Turing-Bedingungen durchgeführt, die unterschiedliche oszillierende Regime zeigen. Das mathematische Modell ist numerisch auf der Basis von DuMuX, einem Open-Source-Code für die Simulation derMehrkomponenten-Mehrphasenströmung und Transports in porösen Medien, implementiert worden. Verschiedene Speicherszenarien wurden simuliert, die die Errichtung des Speichers und die anschließende zyklische Injektion und Produktion über mehrere Jahre umfassen. Es ist bewiesen worden, dass die geringe Dichte und Viskosität von Wasserstoff die Verdrängung von Wasser instabiler macht als bei der Methaninjektion. Darüber hinaus zeigte sich, dass mechanische Dispersion und biochemische Reaktionen einen wichtigen Einfluss in Vorhersagestudien haben. Signifikante Energieverluste können durch biochemische Umwandlungen des gespeicherten Gases auftreten. In this thesis the major differences between underground hydrogen storage and the conventional storage of natural gas are lined out to be bio-reactive and gas mixing phenomena. A new mathematical model was developed to describe the coupling between two-phase flow and microbial populations which consume hydrogen for their metabolism. Different analytical and numerical techniques were applied to investigate the storage of hydrogen in the geological subsurface. An analytical solution was derived for gravity-driven multi-component two-phase flow in heterogeneous porous media. Oscillating scenarios, similar to Turing instability, were detected. Storage scenarios were simulated including a field scale demonstration in a realistic geological model.

This study uses panel cointegration techniques to examine the impact of energy consumption, and trade on economic growth for five North Africa countries within a multivariate framework over the period 1980-2009. Short-run dynamic relationship shows that there is evidence of one way short-run relationship from i) output, exports, and capital to imports, ii) fossil fuels consumption to exports, iii) exports to capital and iv) labor to combustible renewables and waste consumption. The vector error correction model shows that there is evidence of long-run relationship running from i) combustible renewables and waste consumption, fossil fuels consumption, exports, imports, capital, and labor to output, ii) fossil fuels consumption, exports, imports, capital, and labor to combustible renewables and waste consumption, and iii) combustible renewables and waste consumption, fossil fuels consumption, exports, capital, and labor to imports. The long-run elasticities show that combustible renewables and waste consumption is not statistically significant and only fossil fuels consumption can affect output while trade is statistically significant and have a negative impact on output through imports and positive impact through exports. The policy implication of these results is that, in these countries, trade openness is not sufficiently efficient to incite the use of energies for production.

Journal of production systems and logistics 4(10), 1-14 (2024). doi:10.15488/18209 Published by publish-Ing., Offenburg