Validation of a light field camera for investigation on complex plasma

Ekoplasma is going to be the fourth-generation laboratory for the investigation of complex plasmas under microgravity conditions on the International Space Station (ISS). For the first time, particle motion is aimed to be observed three-dimensional by a light field camera under microgravity. The main features of a light field camera were explored. And a three-dimensional calibration target for the validation process was designed and approved. Overall, due to its design this target provides the same capabilities for every imaging system. It therefore is a universal device that will help to develop and classify an imaging system applicable for three dimensional plasma research on the ISS

A Static Layout Algorithm for DiaMeta

The diagram editor generator framework DiaMeta utilizes meta-model-based language specifications and supports free-hand as well as structured editing. In this paper we present a layouting approach that is especially well suited for a static layout. It is based on the layout algorithm presented in a previous paper that uses the two concepts constraint satisfaction and attribute evaluation. This algorithm is combined with graph transformations and the result is a natural way of describing the layout of visual languages. As an example we use a simplified version of Sugiyama's algorithm, applied to statechart diagrams

Combination of Different Layout Approaches

In an interactive environment such as a visual language editor, it is not sufficient to apply the same layout algorithm in every situation. Instead, the user often wants to select the layout behavior at runtime. With the approach presented, the user can control the layout behavior by choosing different layout patterns for different parts of a diagram, e.g., a graph drawing algorithm may be applied to some selected components while others are aligned vertically or horizontally. To enable the specification of layout behavior, we introduced the concept of layout patterns in previous work. Each layout pattern encapsulates certain layout behavior, and hence enables modularization and reuse. To specify user-controlled layout behavior, a flexible combination of arbitrary layout patterns needs to be enabled. Therefore, we introduce an approach that is capable of combining diverse layout approaches, such as standard graph drawing algorithms, constraint-based algorithms, or rule-based layout algorithms. More specifically, an algorithm is presented that automatically computes the complete layout in a straightforward way

A Pattern-based Approach for Initial Diagram Layout

In a diagram editor, one can distinguish initial from incremental diagram layout. The former computes a diagram layout from scratch, whereas the latter adjusts an existing layout after diagram modifications.In previous work, we have proposed a pattern-based approach as a solution for incremental diagram layout in visual language editors. Each LP encapsulates certain layout behavior. A diagram's layout is then defined by simultaneously applying several LPs to the diagram. This solution has been designed for an interactive environment where the user may select and alter the layout behavior at runtime. This paper describes an extension of this approach that now supports initial diagram layout, too. While the old version only enabled freehand editing, the extended version now supports diagram import and structured editing as well

A Pattern-Based Layout Algorithm for Diagram Editors

The diagram editor generator framework DIAMETA utilizes meta-model-based language specifications and supports free-hand as well as structured editing. We presented a generic layout algorithm that meets the demands of this kind of editors. The algorithm combines two concepts, constraint satisfaction and attribute evaluation, to a powerful methodology for specifying the layout for a particular visual language. As the layout specification for this algorithm is rather complex, we encapsulated basic functionality into reusable patterns. This paper describes this pattern concept of the generic layout algorithm, and shows how they simplify the layout specification of a specific language

Pattern-Based Layout Specifications for Visual Language Editors

When creating an editor for a visual language, a challenging task is the layout specification. Many visual languages, e.g., Ecore diagrams or Petri nets, show similar layout characteristics, and hence reuse of layout behavior should be enabled. For that purpose, we introduce the concept of layout patterns, which encapsulates certain layout behavior. With the approach, it is possible to combine different layout algorithms, e.g., standard graph drawing algorithms and constraint-based algorithms. In addition, rule-based layout algorithms may be used that are specifically tailored to the interactive nature of visual language editors

Layout Improvement in Diagram Editors by Automatic Ad-hoc Layout

Layout, in the context of diagram editors, is the positioning of diagram components on the screen. Editor users enjoy automatic layout, but they usually like to control the layout at runtime, too. Our pattern-based layout approach allows for automatic and user-controlled layout at the same time: The diagram editor may automatically apply layout patterns to diagram parts based on syntactic rules provided by the editor developer, but editor users may also select diagram parts and then apply layout patterns to them. For instance, user-selected components may be aligned horizontally and remain aligned even after diagram modifications.This paper describes continued work on pattern-based layout. We present automatic ad-hoc layout which combines automatic and user-controlled layout in a new way. While automatic layout is syntax-based and must be specified by the editor developer in advance, automatic ad-hoc layout is solely based on the current diagram layout. Whenever the layout engine detects a situation where a pattern may be applied with no or only small diagram changes, this layout pattern is automatically applied. For instance, if a set of components is almost horizontally aligned on the screen, the horizontal alignment pattern is automatically applied to these components. Such an editor behavior is known from so-called snap lines in commercial diagram editors. Automatic ad-hoc layout generalizes on these manually programmed layout solutions and offers many additional layout features.This paper describes the concept of automatic ad-hoc layout as well as its integration into a diagram editor framework and discusses issues of this new layout approach

Layout Specification on the Concrete and Abstract Syntax Level of a Diagram Language

A visual language consists of several visual component types, e.g. states or transitions in DFAs. Nowadays, the language itself is usually specified via a meta model. To make a diagram look nice, a layouter is required. This layouter may either operate on the concrete syntax level, i.e., on the visual components, or on the abstract syntax level, i.e., on the model instance. In this paper we present an approach that is capable of specifying a flexible layout on both, the concrete as well as the abstract syntax level of a diagram. The approach uses pattern-based transformations. Besides structured editing, it also supports free-hand editing, a challenging task for the layouter. We introduce how such a specification can be created and examine the advantages and shortcomings of each of either operating on the concrete syntax level or on the abstract syntax level

Exploiting the Layout Engine to Assess Diagram Completions

A practicable approach to diagram completion is to first compute model completions on the abstract syntax level. These can be translated to corresponding diagram changes by the layout engine afterwards. Normally, several different model completions are possible though. One way to deal with this issue is to let the user choose among them explicitly, which is already helpful. However, such a choice step is a quite time-consuming interruption of the editing process. We argue that users often are mainly interested in completions that preserve their original diagram as far as possible. This criterion cannot be checked on the abstract syntax level though. In fact, minimal model changes might still result in enormous changes of the original diagram. Therefore, we suggest to use the layout engine in advance for assessing all possible model completions with respect to the diagram changes they eventually cause

The death of a dream

Der Amerikanische Traum ist in Hunter S. Thompsons Texten ein ständig wiederkehrendes Motiv. Auf der Suche nach dem Traum, war es dem Gonzo-Journalisten nicht genug, die Lage der amerikanischen Nation gegen Ende der 60er Jahre bloß zu schildern, sondern sie zu erleben, um dann keine objektive Wahrheit, sondern seine subjektive Sicht der Dinge niederzuschreiben. Seine Beschreibungen der amerikanischen Nation und deren Traum in seinen Werken Angst und Schrecken in Las Vegas und Angst und Schrecken: Im Wahlkampf ′72 sind kaum positiv. Im Gegenteil. Er verweist sogar auf den Tod des Amerikanischen Traumes und den Verfall Amerikas. Der Traum erscheint ihm in vielerlei Gestalt: in Symbolen, wie zum Beispiel der von Geld und Einfluss regierten Stadt Las Vegas, die Thompsons Alter Ego Raoul Duke als Nervenzentrum des Traums identifiziert; Seine Protagonisten durchleuchten die traditionellen Werte der Gesellschaft und müssen feststellen, dass sie sich bei näherem Betrachten als Heuchelei erweisen - als Mythos, wie eben der Amerikanische Traum selbst. Der Reporter, der auf Grund seines einzigartigen Schreibstils oft als Stiefkind der New Journalists oder gesetzloser Journalist (Outlaw Journalist) bezeichnet wurde, wird von der Angst - der Angst vor dem Untergang alles Guten für das Amerika seiner Meinung nach einmal eingetreten ist - übermannt. In seinen von Halluzinogenen eingefärbten Charakterisierungen entlarvt er die Gesellschaft als korrupt, oberflächlich und gierig. Versteckt hinter dem nationalen Moralkodex und unter dem Vorwand den Amerikanischen Traum zu suchen, erlauben seine Mitmenschen sich dem Journalisten der Freiheit zu berauben, und somit seinen persönlichen Traum zu zerstören. Jedoch nimmt Thompson nicht die Rolle des Moralapostels ein, sondern beweist immer wieder seine Mitschuld an den erschreckenden Zuständen im Amerika der frühen 70er Jahre. Angesichts dessen erfassen den Reporter Angst und Schrecken, die ihn dazu bringen seinen Mitmenschen Streiche zu spielen, Lügen aufzutischen und der Realität mit einer Prise schwarzen Humors ins Auge zu sehen. Aus Frustration mit der Situation verwandelt er den Präsidenten, Polizisten, Politiker und sogar seine Kollegen im Journalismus in Raubtiere, die nach seinem Blut lechzen. Thompson scheint der Einzige zu sein, der sich über den Untergang des einst großen nationalen Mythos Gedanken macht. Mit Hilfe von in den Text eingefügten Interviewtranskripten, Autor- und Herausgebernotizen, Ausschnitten aus Zeitungsartikeln und Zitaten belegte der Journalist seine Theorien über den Verfall der Nation. Am Ende - nach der Wiederwahl Richard Nixons, der für Thompson all das, was in Amerika falsch lief, verkörperte -schien sich Thompson geschlagen zu geben. Die Kernidee des Amerikanischen Traums ist die Hoffnung – Hoffnung auf Veränderung, auf einen neuen Anfang. Auch in Thompsons Texten hat man nie das Gefühl, dass er den wichtigsten Mythos der amerikanischen Nation komplett verwirft. Immerhin hat dieser Mythos schon Jahrhunderte lang Menschen aus verschiedensten Ländern verbunden und motiviert, Amerika zu dem Land zu erbauen, das Thompson so schätze