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The wide distribution of location-acquisition technologies means that large volumes of spatio-temporal data are continuously being accumulated. Positioning systems such as GPS enable the tracking of various moving objects' trajectories, which are usually represented by a chronologically ordered sequence of observed locations. The analysis of movement patterns based on detailed positional information creates opportunities for applications that can improve business decisions and processes in a broad spectrum of industries (e.g., transportation, traffic control, or medicine). Due to the large data volumes generated in these applications, the cost-efficient storage of spatio-temporal data is desirable, especially when in-memory database systems are used to achieve interactive performance requirements.
To efficiently utilize the available DRAM capacities, modern database systems support various tuning possibilities to reduce the memory footprint (e.g., data compression) or increase performance (e.g., additional indexes structures). By considering horizontal data partitioning, we can independently apply different tuning options on a fine-grained level. However, the selection of cost and performance-balancing configurations is challenging, due to the vast number of possible setups consisting of mutually dependent individual decisions.
In this thesis, we introduce multiple approaches to improve spatio-temporal data management by automatically optimizing diverse tuning options for the application-specific access patterns and data characteristics. Our contributions are as follows:
(1) We introduce a novel approach to determine fine-grained table configurations for spatio-temporal workloads. Our linear programming (LP) approach jointly optimizes the (i) data compression, (ii) ordering, (iii) indexing, and (iv) tiering. We propose different models which address cost dependencies at different levels of accuracy to compute optimized tuning configurations for a given workload, memory budgets, and data characteristics. To yield maintainable and robust configurations, we further extend our LP-based approach to incorporate reconfiguration costs as well as optimizations for multiple potential workload scenarios.
(2) To optimize the storage layout of timestamps in columnar databases, we present a heuristic approach for the workload-driven combined selection of a data layout and compression scheme. By considering attribute decomposition strategies, we are able to apply application-specific optimizations that reduce the memory footprint and improve performance.
(3) We introduce an approach that leverages past trajectory data to improve the dispatch processes of transportation network companies. Based on location probabilities, we developed risk-averse dispatch strategies that reduce critical delays.
(4) Finally, we used the use case of a transportation network company to evaluate our database optimizations on a real-world dataset. We demonstrate that workload-driven fine-grained optimizations allow us to reduce the memory footprint (up to 71% by equal performance) or increase the performance (up to 90% by equal memory size) compared to established rule-based heuristics.
Individually, our contributions provide novel approaches to the current challenges in spatio-temporal data mining and database research. Combining them allows in-memory databases to store and process spatio-temporal data more cost-efficiently.
The present thesis looks at cultural conceptualisations in relation to DEATH in Irish English from a Cultural Linguistic perspective and puts a special focus on the diachronic development of these conceptualisations. For the study, a corpus consisting of 1,400 death notices from the Dublin-based national newspaper The Irish Times from 14 historical periods between 1859 and 2023 was compiled, resulting in a highly specialised 70,000-word corpus. First, the manual qualitative analysis of the death notices produced evidence for eight superordinate cultural conceptualisations surrounding DEATH, namely, in the order of their frequency THE DEAD ARE TO BE REMEMBERED OR REGRETTED, DEATH IS SOMETHING POSITIVE, DEATH IS REST, DEATH IS A JOURNEY, DYING IS THE BEGINNING OF ANOTHER LIFE, DEATH IS (NOT) A TABOO, DEATH IS GOD’S WILL, and DEATH IS THE END. These conceptualisations were derived from linguistic expressions in the death notices that have these conceptualisations as a cognitive basis. Second, the quantitative comparison of the individual conceptualisations detected diachronic variation, which is interconnected with historical and social developments in Ireland. The thesis, therefore, illustrates the applicability of Cultural Linguistics as an adequate method for diachronic studies interested in culturally determined developments of conceptualisations.
A new challenger seeks to enter the German party system: Bündnis Sahra Wagenknecht (BSW). With her new party, former Die Linke politician Sahra Wagenknecht combines a left-authoritarian profile (economically left-leaning, but culturally conservative) with anti-US, pro-Russia and anti-elitist stances. This article provides the first large-n academic study of the voter potential of this new party by using a quasi-representative sample (n = 6,000) drawn from a Voting Advice Application-like dataset that comes from a website designed to explore the Bündnis Sahra Wagenknecht’s positions. The results show that congruence with foreign policy positions and anti-elitism are strong predictors of the propensity to vote for the Bündnis Sahra Wagenknecht. In contrast, social/welfare and immigration policies are less predictive for assessing the party’s potential. Among the different socio-demographic groups, the Bündnis Sahra Wagenknecht has a strong potential among baby boomers, the less educated and East Germans. Regarding party voters, the Bündnis Sahra Wagenknecht is favoured by supporters of some minor parties like dieBasis, Freie Wähler and Die PARTEI, but also non-voters. Among the established parties, the party’s potential is high among Die Linke voters and, to a lesser extent, voters of the Social democrats (SPD) and Alternative for Germany (AfD). A potential below the average is reported for the supporters of the Liberals (FDP) and Christian Democrats (CDU/CSU) and most clearly for Green and Volt voters.
Spring Issue
(2024)
This chapter focuses on the features of Article 1's paragraph 1 of the 1951 Convention. The article primarily determines the scope of application of the Convention's ratione personae while outlining the basis of the protection of refugees. Additionally, Article 1 addresses the concerns surrounding the inclusion, cessation, and exclusion of refugees. The chapter then tackles the historical development of the article by considering the instruments used prior to the 1951 Convention. It also cites that the Constitution of the International Refugee Organization appears to contain an ambiguity as to how the refugee notion was perceived, so refugees only became the IRO Constitution's concern when they have valid objections to returning to their home country.
Article 22 1951 Convention
(2024)
This chapter covers the 1951 Convention's Article 22. It explains the provision's aim to grant refugees access to the contracting States' national educational systems. Moreover, Article 22 encompasses learning at all different levels of education in schools, universities, and other educational institutions. However, the provision does not address any issues related to the upbringing of children by their parents. The chapter mentions the relevancy of Article 22 when it comes to durable solutions for refugees in an effort to enable them to integrate into the host country's society. It also discusses the drafting history, declarations, and reservations of Article 22 and the instruments used prior to the 1951 Convention.
This chapter examines the extent of the 1951 Convention's Article 44 and the 1967 Protocol's Article IX. It starts with identifying the standard denunciation clause in Article 44 and Article IX. Multilateral treaties of unlimited duration allow States parties an unconditional right to withdraw. A denunciation releases the denouncing party from any obligation further to perform the treaty in relation to the other parties of the 1967 Protocol. The chapter clarifies that denunciation or withdrawal expresses the same legal concept since it is a procedure initiated unilaterally by a State that wants to terminate its legal engagements under a treaty.
This chapter tackles the analysis and function of Article 43 of the 1951 Convention and Article VIII of the 1967 Protocol. It explains that a multilateral treaty can be enforced when met with necessary conditions, such as the Article 24 of the Vienna Convention on the Law of Treaties (VCLT). The provision also regulates the 1951 Convention's entry into force of States' ratification or accession. The chapter notes that the 1967 Protocol entered into force after Sweden deposited its instrument of accession. It elaborates on the specific details needed for the ratification or accession prior to the entry into force.
This study pushes our understanding of research reliability by reproducing and replicating claims from 110 papers in leading economic and political science journals. The analysis involves computational reproducibility checks and robustness assessments. It reveals several patterns. First, we uncover a high rate of fully computationally reproducible results (over 85%). Second, excluding minor issues like missing packages or broken pathways, we uncover coding errors for about 25% of studies, with some studies containing multiple errors. Third, we test the robustness of the results to 5,511 re-analyses. We find a robustness reproducibility of about 70%. Robustness reproducibility rates are relatively higher for re-analyses that introduce new data and lower for re-analyses that change the sample or the definition of the dependent variable. Fourth, 52% of re-analysis effect size estimates are smaller than the original published estimates and the average statistical significance of a re-analysis is 77% of the original. Lastly, we rely on six teams of researchers working independently to answer eight additional research questions on the determinants of robustness reproducibility. Most teams find a negative relationship between replicators' experience and reproducibility, while finding no relationship between reproducibility and the provision of intermediate or even raw data combined with the necessary cleaning codes.
This chapter focuses on Article 46 of the 1951 Convention and Article X of the 1967 Protocol. It explains the depository of a treaty playing an essential procedural role in ensuring the smooth operation of a multilateral treaty. Article 46 enumerates the Secretary-General's function as a depositary performed by the Treaty Section of the Office of Legal Affairs in the United Nations Secretariat. Similarly, Article X confirms and details the Secretary-General's designation and role as depositary of the 1967 Protocol. The chapter mentions that the enumeration of Article X's depositary notification is exemplary instead of conclusive. It examines the depositoary notifications of declarations, signatures, and researvations under Article 46 and Article X.