Multi-Contact Grasp Interaction for Virtual Environments

The grasping of virtual objects has been an active research field for several years. Solutions providing realistic grasping rely on special hardware or require time-consuming parameterizations. Therefore, we introduce a flexible grasping algorithm enabling grasping without computational complex physics. Objects can be grasped and manipulated with multiple fingers. In addition, multiple objects can be manipulated simultaneously with our approach. Through the usage of contact sensors the technique is easily configurable and versatile enough to be used in different scenarios.

GRASP with Hybrid Path Relinking for Bi-Objective Winner Determination in Combinatorial Transportation Auctions

The procurement of transportation services via large-scale combinatorial auctions involves a couple of complex decisions whose outcome highly influences the performance of the tender process. This paper examines the shipper's task of selecting a subset of the submitted bids which efficiently trades off total procurement cost against expected carrier performance. To solve this bi-objective winner determination problem, we propose a Pareto-based greedy randomized adaptive search procedure (GRASP). As a post-optimizer we use a path relinking procedure which is hybridized with branch-and-bound. Several variants of this algorithm are evaluated by means of artificial test instances which comply with important real-world characteristics. The two best variants prove superior to a previously published Pareto-based evolutionary algorithm.

Survey on haptic rendering of data sets: Exploration of scalar and vector fields

Complementary to automatic extraction processes, Virtual Reality technologies provide an adequate framework to integrate human perception in the exploration of large data sets. In such multisensory system, thanks to intuitive interactions, a user can take advantage of all his perceptual abilities in the exploration task. In this context the haptic perception, coupled to visual rendering, has been investigated for the last two decades, with significant achievements. In this paper, we present a survey related to exploitation of the haptic feedback in exploration of large data sets. For each haptic technique introduced, we describe its principles and its effectiveness.

Changing Europe and The Relevance of Care and The Caring Professions

The aim of the paper is to introduce the challenges of the international care debate of the last ten years in order to grasp basic social needs, to analyse their treatment in the public and private sphere and to look at the orientation of professional answers by the care-professions. The concept of care enhances the societal dealing with - or ignoring of - different forms of dependency on informal and formal personal and social services throughout the life-cycle (child-care, nursing sick or handicapped persons, supporting the elderly) and in special life situations (from help to lone mothers and their children, via help to drug-addicts to help for homeless people). All societies have different approaches to deal with these life-situations, they do so by employ-ing various mixtures of: familial support, mostly provided by women, social politics, organized by the state, public and/or private social services. This welfare-mix shows different combinations of private and public obligations, paid and und unpaid work, professional and laymen's tasks based on a specific understanding of mo-rality and justice embedded in the gender structure and intergenerational relationships. The importance of social work as a profession in this context differs according to the historical developments and cultural traditions. Characteristic for the profile of social work is the rele-vance of a care ethics and the existence of social rights, the tension of mothering and profes-sional methods, the relationship between help, denial and punishment and the ways of institu-tionalisation. The actuality of this debate is closely intertwined with the restructuring of societal bonds in the face of globalisation, the political reorganisation of states, the changes in the living to-gether of different generations and both sexes and the consequences for the organisation and contents of welfare. Looking at Germany and Eastern Europe two new phenomena of social relevance for the dis-cussion of care work and care needs can be taken as an example: the extent of cheap illegal women laborers travelling between east and west, especially Polish women working intermit-tendly in private care for old people and the highly organized traffiking of women from Russia to Germany to work in the sex business. The care debate entails a reframing of welfare issues in the light of social justice between classes, ethnicities and gender groups.

Haptische, visuelle und olfaktorische Sprachen: Westnilotische Wahrnehmungen

Cet article traite des expressions de la perception sensuelle de l’ouest nilotique. La première partie de l’article présente une terminologie ophrésiologique en louo et burun et démontre que cette catégorie lexicale détient aussi une catégorie grammaticale particulière. Phénomènes très rares dans les langues du monde, les termes ophrésiologiques sont seulement présentés sous forme introductive pour encourager davantage les recherches futures. La seconde partie de l’article porte sur les descriptions des couleurs utilisées pour les animaux domestiques. Quand les modalités de l’économie changent, les noms utilisés pour les couleurs des animaux peuvent aussi être employés pour d’autres concepts culturels. La troisième partie de l’article montre que les classificateurs nominaux en mabaan (burun) expriment des principes concernant le toucher en tant que structure cognitive. En conséquence, différents procédés de grammaticalisation sont assumés et corrélés avec des ponctuations dans l’histoire culturelle et mentale des ancêtres des locuteurs de l’ouest nilotique.

A perfect ‘treatment-society’?

The Danish Minister of Social Affairs is a very eager protagonist of quality in treatment, almost searching for the “perfect“ treatment for children, youngsters, disabled, etc. Many expensive research projects dealing with quality management as well as developmental projects have been launched during the latest years in order to improve professional practice. Within that context this article will deal with the relations between paternalism and ignorance and between pro-social behaviour and anti-social treatment in order to grasp “why professions are doing vicious things“. The main focus is concerned with the knowledge field of social pedagogy.

tkCybernetics

tkCybernetics is a simulation software that can be used to create and evaluate simple cybernetic circuits as a combination of lowpass and highpass filters and several nonlinear elements. tkCybernetics has been developed for and successfully applied to introductory courses on biological cybernetics at Bielefeld University. Therefore, it is recommended for students who start learning about cybernetics. Students can quickly grasp the concepts used in the graphical user interface and are able to create their own circuits after a short introduction to the program. Its usefulness for advanced students and researchers is limited to quickly testing circuits. This article provides detailed tutorial information on how to install and work with tkCybernetics for self-learning and for higher education.

Real Walking through Virtual Environments by Redirection Techniques

We present redirection techniques that support exploration of large-scale virtual environments (VEs) by means of real walking. We quantify to what degree users can unknowingly be redirected in order to guide them through VEs in which virtual paths differ from the physical paths. We further introduce the concept of dynamic passive haptics by which any number of virtual objects can be mapped to real physical proxy props having similar haptic properties (i. e., size, shape, and surface structure), such that the user can sense these virtual objects by touching their real world counterparts. Dynamic passive haptics provides the user with the illusion of interacting with a desired virtual object by redirecting her to the corresponding proxy prop. We describe the concepts of generic redirected walking and dynamic passive haptics and present experiments in which we have evaluated these concepts. Furthermore, we discuss implications that have been derived from a user study, and we present approaches that derive physical paths which may vary from the virtual counterparts.

Semiotic Analysis in the Study of Social Work

Research and professional practices have the joint aim of re-structuring the preconceived notions of reality. They both want to gain the understanding about social reality. Social workers use their professional competence in order to grasp the reality of their clients, while researchers’ pursuit is to open the secrecies of the research material. Development and research are now so intertwined and inherent in almost all professional practices that making distinctions between practising, developing and researching has become difficult and in many aspects irrelevant. Moving towards research-based practices is possible and it is easily applied within the framework of the qualitative research approach (Dominelli 2005, 235; Humphries 2005, 280). Social work can be understood as acts and speech acts crisscrossing between social workers and clients. When trying to catch the verbal and non-verbal hints of each others’ behaviour, the actors have to do a lot of interpretations in a more or less uncertain mental landscape. Our point of departure is the idea that the study of social work practices requires tools which effectively reveal the internal complexity of social work (see, for example, Adams & Dominelli & Payne 2005, 294 – 295). The boom of qualitative research methodologies in recent decades is associated with much profound the rupture in humanities, which is called the linguistic turn (Rorty 1967). The idea that language is not transparently mediating our perceptions and thoughts about reality, but on the contrary it constitutes it was new and even confusing to many social scientists. Nowadays we have got used to read research reports which have applied different branches of discursive analyses or narratologic or semiotic approaches. Although differences are sophisticated between those orientations they share the idea of the predominance of language. Despite the lively research work of today’s social work and the research-minded atmosphere of social work practice, semiotics has rarely applied in social work research. However, social work as a communicative practice concerns symbols, metaphors and all kinds of the representative structures of language. Those items are at the core of semiotics, the science of signs, and the science which examines people using signs in their mutual interaction and their endeavours to make the sense of the world they live in, their semiosis. When thinking of the practice of social work and doing the research of it, a number of interpretational levels ought to be passed before reaching the research phase in social work. First of all, social workers have to interpret their clients’ situations, which will be recorded in the files. In some very rare cases those past situations will be reflected in discussions or perhaps interviews or put under the scrutiny of some researcher in the future. Each and every new observation adds its own flavour to the mixture of meanings. Social workers have combined their observations with previous experience and professional knowledge, furthermore, the situation on hand also influences the reactions. In addition, the interpretations made by social workers over the course of their daily working routines are never limited to being part of the personal process of the social worker, but are also always inherently cultural. The work aiming at social change is defined by the presence of an initial situation, a specific goal, and the means and ways of achieving it, which are – or which should be – agreed upon by the social worker and the client in situation which is unique and at the same time socially-driven. Because of the inherent plot-based nature of social work, the practices related to it can be analysed as stories (see Dominelli 2005, 234), given, of course, that they are signifying and told by someone. The research of the practices is concentrating on impressions, perceptions, judgements, accounts, documents etc. All these multifarious elements can be scrutinized as textual corpora, but not whatever textual material. In semiotic analysis, the material studied is characterised as verbal or textual and loaded with meanings. We present a contribution of research methodology, semiotic analysis, which has to our mind at least implicitly references to the social work practices. Our examples of semiotic interpretation have been picked up from our dissertations (Laine 2005; Saurama 2002). The data are official documents from the archives of a child welfare agency and transcriptions of the interviews of shelter employees. These data can be defined as stories told by the social workers of what they have seen and felt. The official documents present only fragmentations and they are often written in passive form. (Saurama 2002, 70.) The interviews carried out in the shelters can be described as stories where the narrators are more familiar and known. The material is characterised by the interaction between the interviewer and interviewee. The levels of the story and the telling of the story become apparent when interviews or documents are examined with the use of semiotic tools. The roots of semiotic interpretation can be found in three different branches; the American pragmatism, Saussurean linguistics in Paris and the so called formalism in Moscow and Tartu; however in this paper we are engaged with the so called Parisian School of semiology which prominent figure was A. J. Greimas. The Finnish sociologists Pekka Sulkunen and Jukka Törrönen (1997a; 1997b) have further developed the ideas of Greimas in their studies on socio-semiotics, and we lean on their ideas. In semiotics social reality is conceived as a relationship between subjects, observations, and interpretations and it is seen mediated by natural language which is the most common sign system among human beings (Mounin 1985; de Saussure 2006; Sebeok 1986). Signification is an act of associating an abstract context (signified) to some physical instrument (signifier). These two elements together form the basic concept, the “sign”, which never constitutes any kind of meaning alone. The meaning will be comprised in a distinction process where signs are being related to other signs. In this chain of signs, the meaning becomes diverged from reality. (Greimas 1980, 28; Potter 1996, 70; de Saussure 2006, 46-48.) One interpretative tool is to think of speech as a surface under which deep structures – i.e. values and norms – exist (Greimas & Courtes 1982; Greimas 1987). To our mind semiotics is very much about playing with two different levels of text: the syntagmatic surface which is more or less faithful to the grammar, and the paradigmatic, semantic structure of values and norms hidden in the deeper meanings of interpretations. Semiotic analysis deals precisely with the level of meaning which exists under the surface, but the only way to reach those meanings is through the textual level, the written or spoken text. That is why the tools are needed. In our studies, we have used the semiotic square and the actant analysis. The former is based on the distinctions and the categorisations of meanings, and the latter on opening the plotting of narratives in order to reach the value structures.

Stereocopic Photography Encounters the Staircase

The staircase is presented as the architectural component that most potently embodies thresholds, boundaries and passages due to its diagonal orientation and essence as an intermediary zone. Connections then are made between the kinesthetic requirements of traversing a staircase and viewing a stereoscopic photograph. From this foundation, the haptic essence of stereoscopic photography is proposed as uniquely qualified medium through which to view a staircase and therefore thresholds, boundaries, and passages within architecture. Analyses of stereoviews of staircases in the Palais de Justice in Brussels, the Library of Congress in Washington, and the Palais Garnier (Opéra) in Paris close the essay.