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Dynamics in urban environments encompasses complex processes and phenomena such as related to movement (e.g.,traffic, people) and development (e.g., construction, settlement). This paper presents novel methods for creating human-centric illustrative maps for visualizing the movement dynamics in virtual 3D environments. The methods allow a viewer to gain rapid insight into traffic density and flow. The illustrative maps represent vehicle behavior as light threads. Light threads are a familiar visual metaphor caused by moving light sources producing streaks in a long-exposure photograph. A vehicle’s front and rear lights produce light threads that convey its direction of motion as well as its velocity and acceleration. The accumulation of light threads allows a viewer to quickly perceive traffic flow and density. The light-thread technique is a key element to effective visualization systems for analytic reasoning, exploration, and monitoring of geospatial processes.
For interactive construction of CSG models understanding the layout of a model is essential for its efficient manipulation. To understand position and orientation of aggregated components of a CSG model, we need to realize its visible and occluded parts as a whole. Hence, transparency and enhanced outlines are key techniques to assist comprehension. We present a novel real-time rendering technique for visualizing design and spatial assembly of CSG models. As enabling technology we combine an image-space CSG rendering algorithm with blueprint rendering. Blueprint rendering applies depth peeling for extracting layers of ordered depth from polygonal models and then composes them in sorted order facilitating a clear insight of the models. We develop a solution for implementing depth peeling for CSG models considering their depth complexity. Capturing surface colors of each layer and later combining the results allows for generating order-independent transparency as one major rendering technique for CSG models. We further define visually important edges for CSG models and integrate an image-space edgeenhancement technique for detecting them in each layer. In this way, we extract visually important edges that are directly and not directly visible to outline a model’s layout. Combining edges with transparency rendering, finally, generates edge-enhanced depictions of image-based CSG models and allows us to realize their complex, spatial assembly.
Information and its individual interpretations are highly discussed in social media. Their use and misuse is an important subject for cultural and media studies. The theoretical framework of this volume is based on a synopsis of socio-constructivist and semiotic paradigms, which permit insight into ongoing adjustments of the social perception of reality and the thereby changing benchmarks. The assembled micro-studies concentrate primarily on right-wing Internet populism in Germany, France and Italy and allow a more precise idea of the effects the disseminated myths, metaphors and memes can have: Becoming viral, they can have an influence on a society’s semiosphere, i.e.on common sense and social life.
Vienna
(2021)
This book explores and debates the urban transformations that have taken place in Vienna over the past 30 years and their consequences in policy fields such as labour and housing, political and social participation and the environment. Historically, European cities have been characterised by a strong association between social cohesion, quality of life, economic ambition and a robust State. Vienna is an excellent example for that. In more recent years, however, cities were pressured to change policy principles and mechanisms in the context of demographic shifts, post-industrial transformations and welfare recalibration which have led to worsened social conditions in many cities. Each chapter in this volume discusses Vienna's responses to these pressures in key policy arenas, looking at outcomes from the context-specific local arrangements. Against a theoretical framework debating the European city as a model of inclusion and social justice, authors explore the local capacity to innovate urban policies and to address new social risks, while paying attention to potential trade-offs.
The book questions and assesses the city's resilience using time series and an institutional analysis of four key dimensions that characterise the European city model within the context of post-industrial transition: redistribution, recognition, representation and sustainability. It offers a multiscalar perspective of urban governance through labour, housing, participatory and environmental policies, bringing together different levels and public policy types.
Contents: 1. Capitalist societies as market-bargaining societies on the basis of resources of action: The idealtypical bargain between capital and labour; an alternative to Marx' theory of exploitation - Discussion of the model 2. A general typology of paths of societies in history and a characterisation of state socialism - People's capitalisms as perspective of development - What remains from Marx' ideas? 3. Variations of welfare capitalism after the decline of state socialism 3.1 National differences of welfare capitalism 3.2 Overall inequality of income and overall class consciousness 3.3 Explaining income inequality and variation in class consciousness by class and gender 3.3.1 A test of different class models in the FRG 3.3.2 Developing an international model of gendered occupational and employment status as bundles of resources of action 4. Summary
Urban neo-liberalisation
(2020)
The contributions to Urban neo- liberalisation bring together critical analyses of the dynamics and processes neo- liberalism has facilitated in urban contexts. Recent developments, such as intensified economic investment and exposure to aggressive strategies of banks, hedge- funds and investors, and long- term processes of market- and state- led urban restructuration, have produced uneven urban geographies and new forms of exclusion and marginality. These strategies have no less transformed the governance of cities by subordinating urban social life to rationalities and practices of competition within and between cities, and they also heavily impact on city inhabitants’ experience of everyday life. Against the backdrop of recent austerity politics and a marketisation of cities, this volume discusses processes of urban neo- liberalisation with regard to democracy and citizenship, inclusion and exclusion, opportunities, and life- chances. It addresses pressing issues of commodification of housing and home, activation of civil society, vulnerability, and the right to the city.
United in Diversity
(2023)
What are the future perspectives for Jews and Jewish networks in contemporary Europe? Is there a new quality of relations between Jews and non-Jews, despite or precisely because of the Holocaust trauma? How is the memory of the extermination of 6 million European Jews reflected in memorial events and literature, film, drama, and visual arts media? To what degree do European Jews feel as integrated people, as Europeans per see, and as safe citizens? An interdisciplinary team of historians, cultural anthropologists, sociologists, and literary theorists answers these questions for Poland, Hungary, the Czech Republic, Slovakia, and Germany. They show that the Holocaust has become an enduring topic in public among Jews and non-Jews. However, Jews in Europe work self-confidently on their future on the "old continent," new alliances, and in cooperation with a broad network of civil forces. Non-Jewish interest in Jewish history and the present has significantly increased over decades, and networks combatting anti-Semitism have strengthened.
Extract-Transform-Load (ETL) tools are used for the creation, maintenance, and evolution of data warehouses, data marts, and operational data stores. ETL workflows populate those systems with data from various data sources by specifying and executing a DAG of transformations. Over time, hundreds of individual workflows evolve as new sources and new requirements are integrated into the system. The maintenance and evolution of large-scale ETL systems requires much time and manual effort. A key problem is to understand the meaning of unfamiliar attribute labels in source and target databases and ETL transformations. Hard-to-understand attribute labels lead to frustration and time spent to develop and understand ETL workflows. We present a schema decryption technique to support ETL developers in understanding cryptic schemata of sources, targets, and ETL transformations. For a given ETL system, our recommender-like approach leverages the large number of mapped attribute labels in existing ETL workflows to produce good and meaningful decryptions. In this way we are able to decrypt attribute labels consisting of a number of unfamiliar few-letter abbreviations, such as UNP_PEN_INT, which we can decrypt to UNPAID_PENALTY_INTEREST. We evaluate our schema decryption approach on three real-world repositories of ETL workflows and show that our approach is able to suggest high-quality decryptions for cryptic attribute labels in a given schema.
Unavailable
(2023)
Two Papers on Clitics
(2000)
Like conventional software projects, projects in model-driven software engineering require adequate management of multiple versions of development artifacts, importantly allowing living with temporary inconsistencies. In the case of model-driven software engineering, employed versioning approaches also have to handle situations where different artifacts, that is, different models, are linked via automatic model transformations.
In this report, we propose a technique for jointly handling the transformation of multiple versions of a source model into corresponding versions of a target model, which enables the use of a more compact representation that may afford improved execution time of both the transformation and further analysis operations. Our approach is based on the well-known formalism of triple graph grammars and a previously introduced encoding of model version histories called multi-version models. In addition to showing the correctness of our approach with respect to the standard semantics of triple graph grammars, we conduct an empirical evaluation that demonstrates the potential benefit regarding execution time performance.
Transmorphic
(2016)
Defining Graphical User Interfaces (GUIs) through functional abstractions can reduce the complexity that arises from mutable abstractions. Recent examples, such as Facebook's React GUI framework have shown, how modelling the view as a functional projection from the application state to a visual representation can reduce the number of interacting objects and thus help to improve the reliabiliy of the system. This however comes at the price of a more rigid, functional framework where programmers are forced to express visual entities with functional abstractions, detached from the way one intuitively thinks about the physical world.
In contrast to that, the GUI Framework Morphic allows interactions in the graphical domain, such as grabbing, dragging or resizing of elements to evolve an application at runtime, providing liveness and directness in the development workflow. Modelling each visual entity through mutable abstractions however makes it difficult to ensure correctness when GUIs start to grow more complex. Furthermore, by evolving morphs at runtime through direct manipulation we diverge more and more from the symbolic description that corresponds to the morph. Given that both of these approaches have their merits and problems, is there a way to combine them in a meaningful way that preserves their respective benefits?
As a solution for this problem, we propose to lift Morphic's concept of direct manipulation from the mutation of state to the transformation of source code. In particular, we will explore the design, implementation and integration of a bidirectional mapping between the graphical representation and a functional and declarative symbolic description of a graphical user interface within a self hosted development environment. We will present Transmorphic, a functional take on the Morphic GUI Framework, where the visual and structural properties of morphs are defined in a purely functional, declarative fashion. In Transmorphic, the developer is able to assemble different morphs at runtime through direct manipulation which is automatically translated into changes in the code of the application. In this way, the comprehensiveness and predictability of direct manipulation can be used in the context of a purely functional GUI, while the effects of the manipulation are reflected in a medium that is always in reach for the programmer and can even be used to incorporate the source transformations into the source files of the application.
Transitional Justice
(2022)
This publication deals with the topic of transitional justice. In six case studies, the authors link theoretical and practical implications in order to develop some innovative approaches. Their proposals might help to deal more effectively with the transition of societies, legal orders and political systems.
Young academics from various backgrounds provide fresh insights and demonstrate the relevance of the topic. The chapters analyse transitions and conflicts in Sierra Leone, Argentina, Nicaragua, Nepal, and South Sudan as well as Germany’s colonial genocide in Namibia. Thus, the book provides the reader with new insights and contributes to the ongoing debate about transitional justice.
International law is constantly navigating the tension between preserving the status quo and adapting to new exigencies. But when and how do such adaptation processes give way to a more profound transformation, if not a crisis of international law? To address the question of how attacks on the international legal order are changing the value orientation of international law, this book brings together scholars of international law and international relations. By combining theoretical and methodological analyses with individual case studies, this book offers readers conceptualizations and tools to systematically examine value change and explore the drivers and mechanisms of these processes. These case studies scrutinize value change in the foundational norms of the post-1945 order and in norms representing the rise of the international legal order post-1990. They cover diverse issues: the prohibition of torture, the protection of women’s rights, the prohibition of the use of force, the non-proliferation of nuclear weapons, sustainability norms, and accountability for core international crimes. The challenges to each norm, the reactions by norm defenders, and the fate of each norm are also studied. Combined, the analyses show that while a few norms have remained surprisingly robust, several are changing, either in substance or in legal or social validity. The book concludes by integrating the conceptual and empirical insights from this interdisciplinary exchange to assess and explain the ambiguous nature of value change in international law beyond the extremes of mere progress or decline.
When realizing a programming language as VM, implementing behavior as part of the VM, as primitive, usually results in reduced execution times. But supporting and developing primitive functions requires more effort than maintaining and using code in the hosted language since debugging is harder, and the turn-around times for VM parts are higher. Furthermore, source artifacts of primitive functions are seldom reused in new implementations of the same language. And if they are reused, the existing API usually is emulated, reducing the performance gains. Because of recent results in tracing dynamic compilation, the trade-off between performance and ease of implementation, reuse, and changeability might now be decided adversely.
In this work, we investigate the trade-offs when creating primitives, and in particular how large a difference remains between primitive and hosted function run times in VMs with tracing just-in-time compiler. To that end, we implemented the algorithmic primitive BitBlt three times for RSqueak/VM. RSqueak/VM is a Smalltalk VM utilizing the PyPy RPython toolchain. We compare primitive implementations in C, RPython, and Smalltalk, showing that due to the tracing just-in-time compiler, the performance gap has lessened by one magnitude to one magnitude.
Since the end of the Apartheid international tourism in South Africa has increasingly gained importance for the national economy. The centre of this PKS issue’s attention is a particular form of tourism: Township tourism, i.e. guided tours to the residential areas of the black population. About 300,000 tourists per year visit the townships of Cape Town. The tours are also called Cultural, Social, or Reality Tours. The different aspects of township tourism in Cape Town were subject of a geographic field study, which was undertaken during a student research project of Potsdam University in 2007. The text at hand presents the empirical results of the field study, and demonstrates how townships are constructed as spaces of tourism.
Version control is a widely used practice among software developers. It reduces the risk of changing their software and allows them to manage different configurations and to collaborate with others more efficiently. This is amplified by code sharing platforms such as GitHub or Bitbucket. Most version control systems track files (e.g., Git, Mercurial, and Subversion do), but some programming environments do not operate on files, but on objects instead (many Smalltalk implementations do). Users of such environments want to use version control for their objects anyway. Specialized version control systems, such as the ones available for Smalltalk systems (e.g., ENVY/Developer and Monticello), focus on a small subset of objects that can be versioned. Most of these systems concentrate on the tracking of methods, classes, and configurations of these. Other user-defined and user-built objects are either not eligible for version control at all, tracking them involves complicated workarounds, or a fixed, domain-unspecific serialization format is used that does not equally suit all kinds of objects. Moreover, these version control systems that are specific to a programming environment require their own code sharing platforms; popular, well-established platforms for file-based version control systems cannot be used or adapter solutions need to be implemented and maintained.
To improve the situation for version control of arbitrary objects, a framework for tracking, converting, and storing of objects is presented in this report. It allows editions of objects to be stored in an exchangeable, existing backend version control system. The platforms of the backend version control system can thus be reused. Users and objects have control over how objects are captured for the purpose of version control. Domain-specific requirements can be implemented. The storage format (i.e. the file format, when file-based backend version control systems are used) can also vary from one object to another. Different editions of objects can be compared and sets of changes can be applied to graphs of objects. A generic way for capturing and restoring that supports most kinds of objects is described. It models each object as a collection of slots. Thus, users can begin to track their objects without first having to implement version control supplements for their own kinds of objects. The proposed architecture is evaluated using a prototype implementation that can be used to track objects in Squeak/Smalltalk with Git. The prototype improves the suboptimal standing of user objects with respect to version control described above and also simplifies some version control tasks for classes and methods as well. It also raises new problems, which are discussed in this report as well.
Towards computer science
(1998)