Resilience at Work - Extending knowledge of resilience in the work context

Diese Dissertation beschäftigt sich mit dem Konzept der Resilienz im Arbeitsumfeld. Drei Forschungsarbeiten liefern einen Beitrag zur Literatur im Bereich der Arbeits- und Organisationspsychologie. In der ersten Studie werden Resilienzskalen miteinander verglichen und im Arbeitskontext validiert. Es wird eine Empfehlung ausgesprochen, welches Messinstrument sich am besten zur Erfassung von Resilienz im Arbeitskontext eignet. Die zweite Studie stellt die Unterschiede zwischen den beiden ähnlichen Konzepten Resilienz und Core Self-Evaluations dar. Zusätzlich wird die kognitive Bewertung von Situationen (Cognitive Appraisal) als Resilienzmechanismus in einem Tagebuchdesign betrachtet. In der dritten Studie wird der regulatorische Fokus von Personen als weiterer Resilienzmechanismus analysiert, um die Zusammenhänge zwischen Resilienz und positiven arbeitsbezogenen Ergebnissen zu erklären. Die Gesamtdiskussion baut auf den Erkenntnissen aus den drei Studien auf und fasst die theoretischen und praktischen Implikationen zusammen. Zusätzlich werden Ideen für die zukünftige Erforschung von Resilienz im Arbeitskontext diskutiert.

A User-Centric Perspective on Parallel Programming with Focus on OpenMP

The process of developing software that takes advantage of multiple processors is commonly referred to as parallel programming. For various reasons, this process is much harder than the sequential case. For decades, parallel programming has been a problem for a small niche only: engineers working on parallelizing mostly numerical applications in High Performance Computing. This has changed with the advent of multi-core processors in mainstream computer architectures. Parallel programming in our days becomes a problem for a much larger group of developers. The main objective of this thesis was to find ways to make parallel programming easier for them. Different aims were identified in order to reach the objective: research the state of the art of parallel programming today, improve the education of software developers about the topic, and provide programmers with powerful abstractions to make their work easier. To reach these aims, several key steps were taken. To start with, a survey was conducted among parallel programmers to find out about the state of the art. More than 250 people participated, yielding results about the parallel programming systems and languages in use, as well as about common problems with these systems. Furthermore, a study was conducted in university classes on parallel programming. It resulted in a list of frequently made mistakes that were analyzed and used to create a programmers' checklist to avoid them in the future. For programmers' education, an online resource was setup to collect experiences and knowledge in the field of parallel programming - called the Parawiki. Another key step in this direction was the creation of the Thinking Parallel weblog, where more than 50.000 readers to date have read essays on the topic. For the third aim (powerful abstractions), it was decided to concentrate on one parallel programming system: OpenMP. Its ease of use and high level of abstraction were the most important reasons for this decision. Two different research directions were pursued. The first one resulted in a parallel library called AthenaMP. It contains so-called generic components, derived from design patterns for parallel programming. These include functionality to enhance the locks provided by OpenMP, to perform operations on large amounts of data (data-parallel programming), and to enable the implementation of irregular algorithms using task pools. AthenaMP itself serves a triple role: the components are well-documented and can be used directly in programs, it enables developers to study the source code and learn from it, and it is possible for compiler writers to use it as a testing ground for their OpenMP compilers. The second research direction was targeted at changing the OpenMP specification to make the system more powerful. The main contributions here were a proposal to enable thread-cancellation and a proposal to avoid busy waiting. Both were implemented in a research compiler, shown to be useful in example applications, and proposed to the OpenMP Language Committee.

Labelling schemes for organic food: Consumer attitudes, preferences and willingness-to-pay in six European countries

Since July 2010, all pre-packed organic food produced in the European Union (EU) must carry the new mandatory EU logo for organic food. Voluntary organic labels (such as national governmental logos and logos of private farmers’ associations and control bodies) can still be used, but only in addition to the mandatory EU logo. This change in the regulatory environment of organic labelling raises a number of questions regarding consumer preferences for different kinds of organic certification logos, which the present dissertation addressed. The first objective was to explore and analyse consumer perceptions, attitudes, preferences and willingness-to-pay (WTP) regarding different voluntary organic labels. The second objective was to investigate consumer perceptions and attitudes towards a mandatory EU logo. A combination of qualitative and quantitative methods of consumer research in six European countries was employed including focus group discussions, choice experiments and structured interviews. Based on the empirical results, recommendations are drawn for different actors in the organic sector.