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Towards Seamless Integration: Exploring Cross-Reality for Extending Physical Office Workspaces
(2026)
Immersive systems, like Augmented and Virtual Reality, offer new paradigms fordigital interaction, but confining users to a single reality often presents drawbacksfor complex tasks. Cross-Reality systems, which integrate multiple realities into asingle experience, have significant potential to enhance existing professional workflows by combining the unique strengths of physical and virtual environments. Thisdissertation investigates how Cross-Reality can enhance professional workflows byusing the traditional office as a primary use case, focusing on the central question:How can CR enhance existing workflows in physical settings by extendingthe physical environment with virtual content and environments?To address this, the dissertation presents a body of empirical work structuredaround isolating and investigating one core design challenge for each of the threeprimary types of Cross-Reality systems. The work first addresses transitionalCross-Reality systems, which allow users to switch between different realities, byexamining how to design effective transitions. It demonstrates that in task-drivenscenarios, users prioritize efficient transitions that minimize cognitive disruptionover more elaborate or interactive ones. Next, the dissertation tackles the fundamental problem of unwanted occlusion in Augmented Virtuality, a form of substitutional Cross-Reality systems, which integrate objects from one reality intoanother. It introduces and evaluates technical strategies to ensure physical toolsremain accessible within virtual spaces, revealing a critical trade-off between theefficacy of these solutions and user experience factors like cybersickness. Finally,the research explores multi-user Cross-Reality systems that enable collaborationbetween multiple users who may be experiencing different degrees of virtualitysimultaneously, and the complexities of enabling collaboration across multiplestages, underscoring the unique challenges of supporting shared awareness andmanaging asymmetric roles.These findings are grounded by a detailed analysis of the underlying hardware, which highlights how technical and perceptual issues inherent to VideoSee-Through and Optical See-Through Head-Mounted Displays directly impactthe feasibility and design of Cross-Reality systems. The overarching contributionof this dissertation is to provide a set of empirically-grounded design principlesfor applying Cross-Reality in productivity-focused environments. By shifting thedesign focus from entertainment to pragmatic qualities, this work offers valuableinsights into creating Cross-Reality systems that genuinely enhance workflows, prioritizing efficiency, usability, and seamless interaction while navigating technical
This thesis presents four contributions in the domains of schema/ontology alignment and query processing. First, we present a novel alignment approach, denoted as FiLiPo (Finding Linkage Points), to align the schema of RDF knowledge bases with the response schema of RESTful Web APIs. FiLiPo only requires knowledge about a knowledge base (e.g., class names) but no prior knowledge about the
Web APIs’ data structure. It uses fifteen different string similarity metrics to find an alignment between the schema of a knowledge base and that of aWeb API.
Next, a benchmark system named ETARA (Evaluation Toolkit for API and RDF Alignment) is introduced that was created with the goal to simulate RESTful Web APIs and is able to cover all important characteristics of Web APIs, i.e., latency, timeouts, rate limits and, furthermore, provides configurable response structures (e.g., JSON or XML). Additionally, it was designed to support researchers during
the development of alignment systems.
Afterward, the alignments determined by FiLiPo are used to create a hybrid and federated query processor named TunA (Tunable Query Optimizer forWeb APIs and User Preferences), which allows SPARQL queries combining knowledge bases and RESTful Web APIs and is tunable towards user preferences, i.e., coverage, reliability and execution time. The primary goal of TunA is to return a query result that satisfies the user’s preferences in terms of data quality, even when using unreliable data sources by performing a majority vote over multiple sources.
Lastly, we present a federated query processor, denoted as ORAQL (Overlap and Reliability Aware Query Processing Layer), which uses overlap information to reduce the number of selected sources that are available in a federation. The goal is to reduce redundant data and, hence, improve the query execution speed. Therefore, ORAQL uses a profile feature that provides information about the overlap between all data sources of a federation. Furthermore, we extend the quality estimation of TunA to cover Triple Pattern Fragment interfaces to ensure a user-provided reliability goal.
This thesis serves as proof of concept for the tensile strength simulation-based nonwoven material design. Objective is the adjustment of the parameters of an underlying production process with regard to a desired tensile strength behavior (optimization). As an example, we focus on the nonwoven airlay production and consider a thermobonding procedure for the consolidation of the nonwoven fabrics.
To be able to map production parameters to the associated tensile strength behavior, we present a model-simulation framework composed of a model for the nonwoven fiber structure generation and a model for the nonwovens’ mechanical behavior under vertical load. The model for the fiber structure generation replicates the stochastic fiber lay-down of the airlay production and results in a random three-dimensional fiber web. This web is consolidated using a virtual bonding procedure that mimics the thermobonding of the nonwoven material. The topology of the resulting adhered fiber structure can be described by a graph, which serves as basis for the subsequent tensile strength simulation. The model used for this purpose describes the mechanical behavior of the material at fiber network level. Therefore, the considered fiber structure sample is interpreted as truss and the fiber connections are equipped with a nonlinear material law, which allows to describe the elastic phase of the nonwovens’ tensile strength behavior. The existence and uniqueness of a solution to the model as well as its numerical treatment are discussed. Moreover, we present data reduction strategies that enable more efficient simulations by removing fiber structure parts that do not contribute to the tensile strength behavior.
As it becomes evident from the numerical experiments, a single tensile strength simulation for a production-like virtual sample is already computational demanding. Costs accumulate further, since Monte-Carlo simulations are required to account for the randomness in the fiber structure generation. Thus, direct simulations provide an infeasible basis for the nonwoven material design. This motivates the use of a predictive surrogate for optimization. Therefore, we consider regression-based approaches at different levels of information within the simulation framework. It turns out that the coupling of a polynomial model, for the fiber structure feature inference, with a linear one, for the stress-strain curve inference, yields accurate predictions. Once trained, the regression models allow for efficient evaluations and thus represent a suitable surrogate for the nonwoven material design. In this context, we discuss two exemplary problems of interest for the application: First, a tracking-type problem that aims to find the production parameters that result in a desired tensile strength behavior, expressed in terms of stress-strain curves. Second, an in-corridor maximization problem, which aims to identify the production parameters that maximize the probability of ending up in a specified stress-strain corridor.
Price indices play a vital role in economic measurement as they reflect price levels
and measure price fluctuations. Price level measures are used with macroeconomic
indicators to express them in real terms. These measures are also used to index wages,
rents, and pensions. Furthermore, they are used as a reference for monetary policy
conducted by central banks. Therefore, the provision of accurate price indices is one
of the most important goals of National Statistical Institutes (NSIs), and numerous
studies have been devoted to this goal.
This cumulative dissertation also contributes to this goal. It contains four chapters,
each of which represents a separate research. The first two studies are devoted to
the treatment of seasonal products by using different price index methods. The first
research is co-authored with Ken van Loon. The third research is dedicated to finding
the most accurate method to make price predictions for missing products. The fourth
research is focused on the treatment of products by using different price index methods
when products’ quality characteristics are available.
The article discusses “SimStab” [Simulator of Stability], a poetic performance by a young Russian poet, Rostislav Amelin, as an effective hybrid of the innovative poetry, video game, and the cyberpunk genre models. The interaction of these components produces strong, yet not necessarily obvious political over-tones, testing the limits of the audience’s (or readers’, or players’) agency. Like many other cyberpunk texts, “SimStab” explores the conflict between the desire to resist colonization by the pervasive powers dominating contemporary society, and the absolute necessity of willingly colonizing your own body and subjectivity with the products of these powers. Both the poem, game and their shared text embody spaces of utopia reliant on repressed sites of formless abjection, which paradoxically become a source of anarchic freedom. Thus, in “SimStab” the ludic algorithmic with its procedural rhetoric (Ian Bogost) creates spaces of formlessness which repeats the liberatory promise of cyberpunk literature.
The Orbita multimedia and poetry collective, based in Riga, Latvia, has succeeded in making poetry written in Russian an integral part of the Latvian cultural and literary scene, despite the burden borne by Russian language and culture in this society as a result of still unsettled and contested histories of Russian and Soviet imperial domination and cultural imperialism. The article explains this achievement as resulting from the Orbita collective’s practices of “performative translation,” which make translation a highly visible and central element of various forms of artistic activity, including multimedia installations, book publishing, video poetry, public performance, proper, and more. In traditional cultural configurations, translation is thought to transfer the essential features or the spirit of a text from one literary language to another in a manner that makes possible the translation’s readers’ sense of unmediated contact with the original. Such a conception of translation supports the monolingual paradigm – the cultural ideology of separate and distinct national languages – and the political actualities to which it corresponds. Orbita’s practices of performative translation, in contrast, create a multilingual heterotopia in which the actuality of translation as mediation is rendered visible, the boundedness and distinctiveness of national literary languages is undermined, and the social necessity and ubiquity of acts of translation is brought to the fore.
The target of this essay is to open possible pathways to approach the phenomenon of a self-remodeling of classicist poetry in the 20th and early 21st century by focusing on the process from two different angles rarely perceived as related to each other: first, the remodeling of Chinese lyrical classicism through a strand of modern American poetry harking back to Ezra Pound and currently crystallized in the translations of David Hinton and, second, the transition that modern Chinese poetry written in classical language and conforming to prosodic rules of classical style poetry, sometimes referred to as “old style poetry” jiu ti shi, underwent after its rebirth as “unofficial” poetry online since the beginning of this century. Although there are obviously no direct links between the aforementioned tradition of modern American poetry and neoclassicist cyberpoets like Zeng Shaoli I argue that in both cases the classicist inspiration and poetic drive is motivated by concern with the increasing imbalance between natural, social, and individual resources, on the one hand, and an indomitable desire to accumulate economic and political power on the other. A permanent devaluation of language in the human realm, matched by a permanent devaluation of currencies in the economic sphere, provokes poetic responses in the very interest of humanity. The neoclassicist lyricisms that I draw into comparison display both subtle distinctions and common traits in this response to the starkly different environments of their respective contemporary literary scenes.
This article considers the evolution of poetic performance on the basis of several Russian poets of the 2010s. The type of performance in question, which originally implied active absorption in the poetic text, occupied an important place in Russian art of the twentieth century – from the first experiments of the historical avant-garde to Moscow Conceptualism (above all, in the their “Collective Actions”). As such, it has always maintained a closeness to the poetic work and was most often practiced by poets who sought to extend their texts beyond the space of the page and into the “external” world. In the 2010s, however, with the development of social media, the opposite trend is noticeable – poets, while declaring their connection to the performative traditions of Moscow Conceptualism, transfer their performative activity into a textual space organized by social media platforms. The central hypothesis of this article is that all of these poets react differently to the methods of discursive organization provided (and enforced) by social networks and strive in different ways to liberate themselves from the censorship of the algorithm: some emphasize the discursive incoherence of the platform, while others, on the contrary, seek to develop a sustainable manner of uniting private discourses into a new totality.
Preliminary Note
(2024)
This volume brings together contributions addressing the intersections of political poetry, performativity, and the internet. The essays are based on presentations given at workshops and conferences organized by the DFG Centre for Advanced Studies “Russian-Language Poetry in Transition: Poetic Forms of Dealing with Boundaries of Genre, Language, Culture and Society between Europe, Asia and America” (2017-2023). The conferences took place in 2018-2019, at a time when neither the coronavirus pandemic nor Russia’s brutal invasion of Ukraine were foreseeable, and the contributions have not been updated in light of these catastrophes. The articles presented here deal with recent poetry and focus on the connection between politics, performativity, and the internet in multiple literatures and intercultural relations. Although the majority of these texts belong to the Russophone world, poetry from Serbia, Latvia, and China is also considered. The contributors demonstrate, on the one hand, how newer poetry softens genre distinctions and formally tends towards multimedia hybridization and, on the other, how it transcends or dissolves linguistic, cultural, and social boundaries. Dr. Ekaterina Friedrichs and Ms. Lena Rosalin Schwarz were involved in preparing this publication for printing. We would like to thank them both for their careful review and wonderful cooperation.