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1021 research outputs found
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Jahrbuch für Tod und Gesellschaft 2024
No full textAuseinandersetzungen mit Sterben, Tod und Trauer sind gesellschaftlich von permanenter Relevanz. Theoretische Zugänge und empirische Analysen zu diesem Themenfeld finden im Jahrbuch für Tod und Gesellschaft ein interdisziplinäres Forum. Neben der Vertiefung aktueller Debatten und der Besprechung von Neuerscheinungen dient das Periodikum der Weiterentwicklung der thanato(-sozio-)logischen Erkenntnis sowie der (inter-)nationalen Vernetzung. Der thematische Horizont der zweiten Ausgabe umfasst u.a. Verwitwung, Foto-Sharing am Lebensende, Death Education und visuelle Tabus in der qualitativen Forschung
Vulnerabilities and capacities : dealing with coastal flooding in Ghana´s Volta Region
No full textCoastal flooding events pose an existential threat to populations around the world, particularly in the Global South. As a result of climate change and other, direct forms of anthropogenic interference, the magnitude and frequency of such floodings is predicted to continuously increase in the near future. Therefore, it is important to understand the vulnerability of affected people to implement appropriate measures. This research presents a case study on coastal flooding and its impact on livelihoods in the Volta Region of Ghana. The paper utilizes a vulnerability framework that focuses on exposure, susceptibility, as well as the capacities to anticipate, cope with, and recover from the effects of natural hazards. Based on a qualitative approach, the study focusses on those households who were directly affected of a severe tidal flood in November 2021, leading to a total destruction of their property. The research was conducted in March, July and August 2022. It revealed that the studied group had low capacity to anticipate and had no contingency plans in case of relocation. Further, we discovered different strategies that people applied to deal with the situation eight months after the flood event. Most households applied (short term) coping strategies to reestablish their former marine-based livelihood systems. Adaption in terms of long-term adjustment of their livelihoods played only a minor role and could be found in form of out-migration in a limited number of households
Long short-term renewable energy sources prediction for grid-management systems based on stacking ensemble model
No full textThe transition towards sustainable energy systems necessitates effective management of renewable energy sources alongside conventional grid infrastructure. This paper presents a comprehensive approach to optimizing grid management by integrating Photovoltaic (PV), wind, and grid energies to minimize costs and enhance sustainability. A key focus lies in developing an accurate scheduling algorithm utilizing Mixed Integer Programming (MIP), enabling dynamic allocation of energy resources to meet demand while minimizing reliance on cost-intensive grid energy. An ensemble learning technique, specifically a stacking algorithm, is employed to construct a robust forecasting pipeline for PV and wind energy generation. The forecasting model achieves remarkable accuracy with a Root Mean Squared Error (RMSE) of less than 0.1 for short-term (15 min and one day ahead) and long-term (one week and one month ahead) predictions. By combining optimization and forecasting methodologies, this research contributes to advancing grid management systems capable of harnessing renewable energy sources efficiently, thus facilitating cost savings and fostering sustainability in the energy sector
Running in the Hamster Wheel. The Foreign Policy of Serbia between National Identity and the International Society.
No full textThe thesis addresses a current topic related to the foreign policy of Serbia whereby Serbian foreign policy is analysed with reference to its domestic factors - in particular national identity - and also with regards to Serbia’s foreign factors, such as the Europeanization process and the nature of the international system. The overarching focus of the thesis is laid on the following puzzle: in spite of not attaining self-declared foreign policy goals and changing dynamics at the systemic level, Serbia’s foreign policy appear to be stable over time. In each of the five publications comprising the thesis, a narrower aspect of this puzzle is addressed
Improving Automated Android Test Generation
No full textMobile apps are nowadays the preferred means to accomplish ubiquitous tasks like messaging, e-commerce and even playing games. Often, there exist multiple apps for the same purpose, and it is the choice of the end user to pick an appropriate app. Apps that behave unexpected, e.g., crash frequently, are sooner or later replaced, which isundesirable for the companies developing such apps. Thus, it is essential to tests apps properly before they are released onto the market. However, testing manually is often not only too cost-intensive but also too time-consuming in the short development phase, thus an automated solution is preferred. Testing mobile apps automatically received increased attention in the last decade from primarily people in academia, and several testing techniques evolved. One technique that yielded promising results, especially in different domains, is search-based software testing in which a metaheuristic, e.g., a genetic algorithm, is applied to solve an optimisation problem, e.g., test generation. A main objective of test generation is to produce tests that reveal as many faults as possible.
This in turn requires the generation of tests that deeply explore the tested app. The core metric to quantify how much code tests cover is the measurement of code coverage, which can be computed at different levels of granularity ranging from determining the fraction of covered activities to a very fine-grained measurement that calculates the percentage of covered lines. This coverage information is then often used to guide the search of the employed metaheuristic.
However, current automated test generation approaches produce tests with a rather low code coverage. Thus, a substantial part of tested apps remains unexplored, which in turn misses revealing deeply residing faults. We identified three core issues that are directly related to the generation of low-coverage tests. First, the applicability of current test generators is often limited. This comprises the fact that current state-of-the-art code coverage tools are incapable of instrumenting a substantial number of apps and consequently, test generators cannot utilise detailed coverage information during exploration.
In addition, test generators are often only equipped with a primitive set of actions that are insufficient to simulate system events and complex user inputs. Second, the test execution is extremely time-consuming. This includes among other things the overhead associated with executing individual actions, intermediate restart operations as well as fitness evaluations. Since search-based algorithms require a substantial number of test executions to play out their strengths, the slow test execution impedes the effectiveness of the search. Third, the guidance offered by search-based algorithms is often hampered by applying inadequate fitness functions or by using non-representation-specific variation operators.
In this thesis we address the problem of low-coverage tests in the Android domain by proposing several enhancements for the three identified core issues. Concerning the applicability problem, we provide the implementation of a robust code coverage tool that is capable of measuring coverage at different levels of granularity and requires no access to the source code. We also propose to include actions that can simulate system events as well as complex user inputs. Regarding the performance issue, we suggest the integration of a surrogate model that is capable of predicting the outcome of individual actions or complete tests over time in order to reduce the overall test execution costs. With respect to the lack of guidance offered by traditional search-based algorithms, we suggest alternative search strategies. In the case of a deceptive fitness landscape, we propose using novelty search algorithms. Alternatively, we suggest utilising estimation of distribution algorithms that require no crossover or mutation perators to sample new tests. While all those enhancements had a positive impact on the Android test generation process, the individual empirical studies highlighted that further research is necessary to unleash the full power of the proposed search-based algorithms. In particular, exploring complex user interfaces meaningfully requires more attention whether by introducing additional actions or by extracting valuable hints to infer reasonable text inputs. In addition, the guidance offered by fitness functions is often limited because they are either designed too coarse at all or do not accurately reflect the search objectives
Grenzschutz gegen illegale Einwanderung im Bundesstaat : ein Vergleich der rechtlichen Situation in der Bundesrepublik Deutschland und in den Vereinigten Staaten von Amerika
No full textDie Arbeit untersucht aus rechtsvergleichender Perspektive die Thematik des Grenzschutzes gegen illegale Einwanderung in den Bundesstaaten der Vereinigten Staaten von Amerika sowie der Bundesrepublik Deutschland, dort unter Berücksichtigung des Einflusses der Europäischen Union. Betrachtet werden insbesondere die Kompetenzverteilung und föderale Konfliktlösungsmechanismen, einschließlich der Möglichkeit, Streitigkeiten zwischen dem Bund und den Gliedstaaten gerichtlich klären zu lassen
Evaluating Poverty Alleviation: Essays on Microfinance, Energy Access and Limits to the Gold Standard in Empirical Economics
No full textIn my dissertation, I combine topical contributions on microfinance and energy access, two prevalent poverty alleviation policies, with methodological contributions on how empirical economics research can contribute to effective policymaking. Chapter 1 reviews the existing experimental evidence on microfinance. We use this deep literature to highlight challenges in generalizing from empirical research. Chapter 2 and 3 provide empirical insights on the energy access-poverty nexus. We study the long-term adoption of grid electrification and evaluate whether productive use can foster adoption and impact. Chapter 4 addresses data quality, an essential yet often overlooked element in research and policymaking. This introduction provides a general overview on microfinance, energy access, and methodological critiques on common practices in empirical economics research.
[from the introduction
Arousal, interindividual differences and temporal binding a psychophysiological study
No full textThe sense of agency varies as a function of arousal in negative emotional contexts. As yet, it is unknown whether the same is true for positive affect, and how inter-individual characteristics might predict these effects. Temporal binding, an implicit measure of the sense of agency, was measured in 59 participants before and after watching either an emotionally neutral film clip or a positive film clip with high or low arousal. Analyses included participants’ individual differences in subjective affective ratings, physiological arousal (pupillometry, skin conductance, heart rate), striatal dopamine levels via eye blink rates, and psychopathy. Linear mixed models showed that sexual arousal decreased temporal binding whereas calm pleasure had no facilitation effect on binding. Striatal dopamine levels were positively linked whereas subjective and physiological arousal may be negatively associated with binding towards actions. Psychopathic traits reduced the effect of high arousal on binding towards actions. These results provide evidence that individual differences influence the extent to which the temporal binding is affected by high arousing states with positive valence
Do We Use Relatively Bad (Algorithmic) Advice? The Effects of Performance Feedback and Advice Representation on Advice Usage
No full textAlgorithms are capable of advising human decision‐makers in an increasing number of management accounting tasks such as business forecasts. Due to expected potential of these (intelligent) algorithms, there are growing research efforts to explore ways how to boost algorithmic advice usage in forecasting tasks. However, algorithmic advice can also be erroneous. Yet, the risk of using relatively bad advice is largely ignored in this research stream. Therefore, we conduct two online experiments to examine this risk of using relatively bad advice in a forecasting task. In Experiment 1, we examine the influence of performance feedback (revealing previous relative advice quality) and source of advice on advice usage in business forecasts. The results indicate that the provision of performance feedback increases subsequent advice usage but also the usage of subsequent relatively bad advice. In Experiment 2, we investigate whether advice representation, that is, displaying forecast intervals instead of a point estimate, helps to calibrate advice usage towards relative advice quality. The results suggest that advice representation might be a potential countermeasure to the usage of relatively bad advice. However, the effect of this antidote weakens when forecast intervals become less informative
Effect of mandatory sustainability performance disclosures on firm value: Evidence from listed European firms
No full textCorporate Sustainability Performance (CSP) reporting is becoming increasingly important to investors who seek to identify and invest in companies that are managing their Environmental, Social and Governance (ESG) risks effectively. The European Union's Non‐Financial Reporting Directive (NFRD), which was implemented in 2017, mandates that certain large companies must disclose their sustainability performance. This study examines the impact of the EU NFRD on the firm value of listed European firms using a difference‐in‐differences regression model. We find that the mandatory disclosure of corporate sustainability performance does not significantly affect firm value at an aggregate level. However, the results suggest minor inter‐industry differences, which can be attributed to varying sustainability performance metrics across industries. These findings contribute not only to the nascent literature on mandatory sustainability disclosures but also to the deliberations of policymakers and regulators across the world who are devising and implementing mandatory corporate sustainability performance disclosure regulations