C-diagrams, shifts and solidarity values

In the theory of cooperative games so called dividends of a coalition $S$ are considered, which are defined as $\frac{c_S}{|S|}$. The costs $c_S$ form a c-diagram. On these c-diagrams several types of shifts are defined and analysed. Different solution concepts and their properties are related to shifts. We introduce reward games and fine games as components of a cooperative game. Some solution concepts for applications are analysed in terms of c-diagrams, as well as the solidarity concept. \u

Exobiology on Mars

Descriptions of several instrument concepts that were generated during a workshop entitled, Exobiology Instrument Concepts for a Soviet Mars 94/94 Mission, held at NASA Ames Research Center in 1989 are presented. The objective was to define and describe instrument concepts for exobiology and related science that would be compatible with the mission types under discussion for the 1994 and 1996 Soviet Mars missions. Experiments that use existing technology were emphasized. The concepts discussed could also be used on U.S. missions that follow Mars Observer

Exploring Central Platform Types and Related Concepts in Service Research – A Systematic Literature Review

Service exchange is considered as an integral component of digital platforms. Academic research differentiates between technical, economic, and social platforms, yet scholars face a multitude of diverse platform sub-types being inconsistently utilized. To address that issue and to provide a lexical platform definition overview, this study conducts a systematic scoping literature review on platform types and related concepts in the service domain. The systematic analysis of 49 high-quality service journal articles reveals that numerous digital platform sub-types exist in service research with overlapping definitions. Moreover, several relationship marketing constructs are investigated as central related concepts. This article is the first to explore divergent platform term definitions in the service domain and thus contributes a complementary service science lens on digital platforms alongside IS research

Multilayer Networks

In most natural and engineered systems, a set of entities interact with each other in complicated patterns that can encompass multiple types of relationships, change in time, and include other types of complications. Such systems include multiple subsystems and layers of connectivity, and it is important to take such "multilayer" features into account to try to improve our understanding of complex systems. Consequently, it is necessary to generalize "traditional" network theory by developing (and validating) a framework and associated tools to study multilayer systems in a comprehensive fashion. The origins of such efforts date back several decades and arose in multiple disciplines, and now the study of multilayer networks has become one of the most important directions in network science. In this paper, we discuss the history of multilayer networks (and related concepts) and review the exploding body of work on such networks. To unify the disparate terminology in the large body of recent work, we discuss a general framework for multilayer networks, construct a dictionary of terminology to relate the numerous existing concepts to each other, and provide a thorough discussion that compares, contrasts, and translates between related notions such as multilayer networks, multiplex networks, interdependent networks, networks of networks, and many others. We also survey and discuss existing data sets that can be represented as multilayer networks. We review attempts to generalize single-layer-network diagnostics to multilayer networks. We also discuss the rapidly expanding research on multilayer-network models and notions like community structure, connected components, tensor decompositions, and various types of dynamical processes on multilayer networks. We conclude with a summary and an outlook.Comment: Working paper; 59 pages, 8 figure

Visual representation of concepts : exploring users’ and designers’ concepts of everyday products

To address the question on how to enhance the design of user-artefact interaction at the initial stages of the design process, this study focuses on exploring the differences between designers and users in regard to their concepts of an artefact usage. It also considers that human experience determines people’s knowledge and concepts of the artefacts they interact with, and broadens or limits their concept of context of use. In this exploratory study visual representation of concepts is used to elicit information from designers and users, and to explore how these concepts are influenced by their individual experience. Observation, concurrent verbal and retrospective protocols and thematic interviews are employed to access more in depth information about users’ and designers’ concepts. The experiment was conducted with designers and users who were asked about their concepts of an everyday product. Three types of data were produced in each session: sketches, transcriptions from retrospectives verbal reports and observations. Through an iterative process, references about context, use and experience were identified in the data collected; this led to the definition of a coding system of categories that was applied for the interpretation of visuals and texts. The methodology was tested through preliminary studies. Their initial outcomes indicate that the main differences between designers’ and users’ concepts come from their knowledge domain, while main similarities are related to human experience as source that drives concept formulation. Cultural background has been found to influence concepts about product usability and its context of use. The use of visual representation of concepts with retrospective reports and interviews allowed access to insightful information on how human experience influence people’s knowledge about product usability and its context of use. It is expected that this knowledge contributes to the enhancement of the design of product usability

A framework for pathologies of message sequence charts

This is the post-print version of the final paper published in Information Software and Technology. The published article is available from the link below. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. Copyright @ 2012 Elsevier B.V.Context - It is known that a Message Sequence Chart (MSC) specification can contain different types of pathology. However, definitions of different types of pathology and the problems caused by pathologies are unclear, let alone the relationships between them. In this circumstance, it can be problematic for software engineers to accurately predict the possible problems that may exist in implementations of MSC specifications and to trace back to the design problems in MSC specifications from the observed problems of an implementation. Objective - We focus on generating a clearer view on MSC pathologies and building formal relationships between pathologies and the problems that they may cause. Method - By concentrating on the problems caused by pathologies, a categorisation of problems that a distributed system may suffer is first introduced. We investigate the different types of problems and map them to categories of pathologies. Thus, existing concepts related to pathology are refined and necessary concepts in the pathology framework are identified. Finally, we formally prove the relationships between the concepts in the framework. Results - A pathology framework is established as desired based on a restriction that considers problematic scenarios with a single undesirable event. In this framework, we define disjoint categories of both pathologies and the problems caused; the identified types of pathology are successfully mapped to the problems that they may cause. Conclusion - The framework achieved in this paper introduces taxonomies into and clarifies relationships between concepts in research on MSC pathologies. The taxonomies and relationships in the framework can help software engineers to predict problems and verify MSC specifications. The single undesirable event restriction not only enables a categorisation of pathological scenarios, but also has the potential practical benefit that a software engineer can concentrate on key problematic scenarios. This may make it easier to either remove pathologies from an MSC specification MM or test an implementation developed from MM for potential problems resulting from such pathologies