The land-use sector can contribute to climate change mitigation not only by reducing greenhouse gas (GHG) emissions, but also by increasing carbon uptake from the atmosphere and thereby creating ...negative CO2 emissions. In this paper, we investigate two land-based climate change mitigation strategies for carbon removal: (1) afforestation and (2) bioenergy in combination with carbon capture and storage technology (bioenergy CCS). In our approach, a global tax on GHG emissions aimed at ambitious climate change mitigation incentivizes land-based mitigation by penalizing positive and rewarding negative CO2 emissions from the land-use system. We analyze afforestation and bioenergy CCS as standalone and combined mitigation strategies. We find that afforestation is a cost-efficient strategy for carbon removal at relatively low carbon prices, while bioenergy CCS becomes competitive only at higher prices. According to our results, cumulative carbon removal due to afforestation and bioenergy CCS is similar at the end of 21st century (600-700 GtCO2), while land-demand for afforestation is much higher compared to bioenergy CCS. In the combined setting, we identify competition for land, but the impact on the mitigation potential (1000 GtCO2) is partially alleviated by productivity increases in the agricultural sector. Moreover, our results indicate that early-century afforestation presumably will not negatively impact carbon removal due to bioenergy CCS in the second half of the 21st century. A sensitivity analysis shows that land-based mitigation is very sensitive to different levels of GHG taxes. Besides that, the mitigation potential of bioenergy CCS highly depends on the development of future bioenergy yields and the availability of geological carbon storage, while for afforestation projects the length of the crediting period is crucial.
The objective of this essay is a holistic view of aesthetics, ethics, and neuroaesthetics. After a few introductory case studies, aesthetics is systematically introduced as a philosophical ...subdiscipline. This perspective is then expanded from aesthetics to neuroaesthetics. Using various art forms as well as current media formats, the aspects of beauty and ugliness are discussed, and aesthetic properties are expanded to include ethical implications. These can be expressed through ideals of beauty and the compulsion for body transformation. This perspective is then expanded from aesthetics to neuroaesthetics. From this point of view of art, the so‐called golden ratio will play a central role. It will be shown how representations affect people and what ethical implications are associated with the effects. Therefore, this essay first has to look at art from the perspective of neuroaesthetics, and then consider the ethical aspects of the beautiful and the ugly. The considerations lead to a brief discussion of Socrates's three sieves.
Contemporary public debates are often characterized by structural and substantial dissonances. This paper is concerned with normative and empirical evaluations of these dissonances and makes ...contributions on both levels. We argue that agonistic pluralism provides an insightful, yet often dismissed, theoretical perspective on the matter of political fragmentation. On the empirical level, we exemplify these considerations against the backdrop of the 2016 Austrian presidential elections and propose a corresponding measurement approach for political fragmentation. A combined network analysis and automated content analysis of comments on Facebook pages affiliated with political parties results in the following main findings: First, when looking at comments between different parties, fragmentation is at a low level at the beginning of the election campaign but increases over time. Second, degrees of fragmentation vary to a great extent between different parties. Third, offensive speech is one purpose for communication between political groups but not the main one.
This study investigates the use of bioenergy for achieving stringent climate stabilization targets and it analyzes the economic drivers behind the choice of bioenergy technologies. We apply the ...integrated assessment framework REMIND-MAgPIE to show that bioenergy, particularly if combined with carbon capture and storage (CCS) is a crucial mitigation option with high deployment levels and high technology value. If CCS is available, bioenergy is exclusively used with CCS. We find that the ability of bioenergy to provide negative emissions gives rise to a strong nexus between biomass prices and carbon prices. Ambitious climate policy could result in bioenergy prices of 70 $/GJ (or even 430 $/GJ if bioenergy potential is limited to 100 EJ/year), which indicates a strong demand for bioenergy. For low stabilization scenarios with BECCS availability, we find that the carbon value of biomass tends to exceed its pure energy value. Therefore, the driving factor behind investments into bioenergy conversion capacities for electricity and hydrogen production are the revenues generated from negative emissions, rather than from energy production. However, in REMIND modern bioenergy is predominantly used to produce low-carbon fuels, since the transport sector has significantly fewer low-carbon alternatives to biofuels than the power sector. Since negative emissions increase the amount of permissible emissions from fossil fuels, given a climate target, bioenergy acts as a complement to fossils rather than a substitute. This makes the short-term and long-term deployment of fossil fuels dependent on the long-term availability of BECCS.
Video-based fire detection is a crucial object detection problem that relies on accurate and reliable data to detect fires. However, collecting and labeling fire-related data can be time-consuming ...and expensive, making it difficult to obtain sufficient data for training machine learning models. To address this challenge, uncertainty-based active learning techniques can be used to iteratively select the most informative samples for labeling. This can reduce the amount of labeled data needed to achieve high model performance and has the potential to even prune the training data with fewer informative samples. The traditional sampling-based uncertainty estimation methods are computationally expensive. Hence, an efficient prior network-based ensemble distillation State-of-the-Art approach is evaluated on an internal dataset which still requires relatively higher overhead computation making it difficult for production deployment. A biased softmax differencing-based uncertainty approach and a feature-based hard data mining approach are proposed and compared with the distillation approach. The novel approaches are found to have a very low overhead uncertainty estimation time compared to the ensemble distillation approach and traditional sampling techniques. The methods are evaluated in the context of curating the unlabeled pool data and improving the training data. For completeness, the experiments are performed on three different data sizes, and overall, the frame-wise selection strategy is proved to be better than the sequence-wise querying strategy. The Principal Component Analysis (PCA)-based hard data mining outperformed other methods and improved the model performance by 16.33% with AUC2% metric when compared with the random selection of data. The approach even outperformed the main network trained on full data by 7.33%, henceforth improving the training data by using informative 26.39% data. The results indicate that novel data mining provides efficient training and pool data curation
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 1999.
Vita.
Includes bibliographical references.
The synthesis and structure of several Zr(IV) carboxylate complexes are ...described in which the bridging carboxylate is the dianion of 111-xylylenediamine bis(Kemp's triacid imide) (H2XDK) or the more soluble propyl derivative (H2PXDK). Reaction of either H2XDK or H2PXDK with Zr(CH2Ph)4 or Zr(NMe2)4 afforded Zr(CH2Ph)2(XDK) or Zr(NMe2)2(XDK). Zr(CH2Ph)2(XDK) is a rare example of an alkyl zirconium carboxylate complex. Zr(CH2Ph)2(XDK) reacts with various pyridine derivatives to yield the 7-coordinate pyridine adduct. An aryl isocyanide (2 equiv) reacts with Zr(CH2Ph)2(XDK) to afford the iminoacyl complex Zr{11 2 -2,6- Me2PhNCCH2Ph}2(XDK). Zr(CH2Ph)2(XDK) is unreactive, however, towards weak sigma donors such as CO. The eight-coordinate complex Zr(XDK)2 was formed by either treating Zr(NMe2)4 with H2XDK (2 equiv) or Zr(CH2Ph)2(XDK) with H2XDK. Several of these complexes have been characterized by X-ray crystallography. Zr(CH2Ph)2(XDK) is electrophilic since the ipso carbon of one benzyl group is interacting with the Zr center as revealed by the acute Zr-C-C(ipso) angle in the X-ray structure of Zr(CH2Ph)2(XDK). These studies have shown that 6-coordinate Zr carboxylate complexes are electrophilic. Complexes of this type are most stable when they possess high coordination numbers; this trend is exemplified by the stability of Zr(XDK)2 and Zr(eta)rt2-2,6-Me2PhNCCH2Phh(XDK).
by Dietrich P. Steinhubel.
Ph.D.
The book of Samuel tells the story of the origins of kingship in Israel in what seems to be an artistically structured, flowing narrative. Yet it is also marked by an inconsistent outlook, divergent ...styles, and breaks in the narrative. According to Noth’s Deuteronomistic History hypothesis, the Deuteronomistic historian constructed the narrative by piecing together early sources and generally refrained from commenting in his own voice. Recent studies have called into question the extent of Samuel’s sources and their redaction history, as well as the textual growth of the book as a whole. The essays in this book, representing the latest scholarship on this subject, reexamine whether the book of Samuel was ever part of a Deuteronomistic History. The contributors are A. Graeme Auld, Hannes Bezzel, Philip R. Davies, Walter Dietrich, Cynthia Edenburg, Jeremy M. Hutton, Jürg Hutzli, Ernst Axel Knauf, Reinhard Müller, Richard D. Nelson, Christophe Nihan, K. L. Noll, Juha Pakkala, and Jacques Vermeylen.
The current conceptualization of Alzheimer disease (AD) is driven by the amyloid hypothesis, in which a deterministic chain of events leads from amyloid deposition and then tau deposition to ...neurodegeneration and progressive cognitive impairment. This model fits autosomal dominant AD but is less applicable to sporadic AD. Owing to emerging information regarding the complex biology of AD and the challenges of developing amyloid-targeting drugs, the amyloid hypothesis needs to be reconsidered. Here we propose a probabilistic model of AD in which three variants of AD (autosomal dominant AD, APOE ε4-related sporadic AD and APOE ε4-unrelated sporadic AD) feature decreasing penetrance and decreasing weight of the amyloid pathophysiological cascade, and increasing weight of stochastic factors (environmental exposures and lower-risk genes). Together, these variants account for a large share of the neuropathological and clinical variability observed in people with AD. The implementation of this model in research might lead to a better understanding of disease pathophysiology, a revision of the current clinical taxonomy and accelerated development of strategies to prevent and treat AD.
The electrolyte filling process constitutes the interface between cell assembly and formation of lithium ion batteries. Electrolyte filling is known as a quality critical and also time consuming ...process step. To avoid limitations in battery quality a homogeneous electrolyte distribution is necessary. Therefore, especially large sized cells are stored for hours. To accelerate filling and wetting processes the effect of materials- and process parameters on electrolyte distribution needs to be investigated. Unfortunately, in situ methods to characterize the filling and wetting state are still rare, limited in availability or even time-consuming in preparation. To overcome these drawbacks this paper introduces X-ray as an innovative method to visualize the electrolyte filling process in large scaled lithium ion batteries. Therefore, an experimental setup was developed to enable in situ X-ray measurements during the filling process of large scaled cells. Additionally, an evaluation process for the optical data was proposed. Based on these images the suitability of X-ray as visualization method is shown considering three exemplary filling parameters.
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