Function-based single and dual point haptic interaction in Cyberworlds

Polygon and point based models dominate virtual reality. These models also affect haptic rendering algorithms, which are often based on collision with polygons. With application to dual point haptic devices for operations like grasping, complex polygon and point based models will make the collision detection procedure slow. This results in the system not able to achieve interactivity for force rendering. To solve this issue, we use mathematical functions to define and implement geometry (curves, surfaces and solid objects), visual appearance (3D colours and geometric textures) and various tangible physical properties (elasticity, friction, viscosity, and force fields). The function definitions are given as analytical formulas (explicit, implicit and parametric), function scripts and procedures. We proposed an algorithm for haptic rendering of virtual scenes including mutually penetrating objects with different sizes and arbitrary location of the observer without a prior knowledge of the scene to be rendered. The algorithm is based on casting multiple haptic rendering rays from the Haptic Interaction Point (HIP), and it builds a stack to keep track on all colliding objects with the HIP. The algorithm uses collision detection based on implicit function representation of the object surfaces. The proposed approach allows us to be flexible when choosing the actual rendering platform, while it can also be easily adopted for dual point haptic collision detection as well as force and torque rendering. The function-defined objects and parts constituting them can be used together with other common definitions of virtual objects such as polygon meshes, point sets, voxel volumes, etc. We implemented an extension of X3D and VRML as well as several standalone application examples to validate the proposed methodology. Experiments show that our concern about fast, accurate rendering as well as compact representation could be fulfilled in various application scenarios and on both single and dual point haptic devices.

Discourses of anxiety in nursing practice : a psychoanalytic case study of the change-of-shift handover ritual

This paper reports on the findings of a study that considered how anxiety might function to organise nurses' practice. With reference to psychoanalytic theory this paper analyses field notes taken during a series of nursing change-of-shift handovers. The handover practices analysed met all the criteria for a ritual, as understood in psychoanalytic theory, and functioned to alleviate anxiety in the short term while symbolically expressing a forbidden and unknown knowledge. We argue that the handover ritual contained certain prohibitions, yet allowed some expression of the prohibited knowledge in a disguised way. The prohibition concerned how the patient affected the nurse, that is, moved the nurse to love and hate the patient. We argue that this prohibition is expressed, in disguise, via the displacement of affection for the patient onto other nurses and through negative stereotyping of some patients. We also argue that these prohibitions of the handover mirror broader prohibitions within nursing, and thus the rituals of the handover become an expression of how professional prohibitions are enacted in practice. We conclude that the important implicit function of the handover ritual is to keep anxiety at bay, thereby enabling the nurse to commence practice rather than being immobilised by the effect of potentially overwhelming anxiety.

Second person : a point of view? The function of the second person pronoun in narrative prose fiction

This thesis looks at the functions and effects of the ‘second-person’ pronoun in narrative prose fiction, with particular focus on the fluidity and ambiguity of the mode that I will call Protean-'you.' It is a mode in which it is unclear whether the ‘you’ is a character, the narrator, a reader/narratee, or no-one in particular—or a combination of these—so that readers find ‘second-person’ utterances at once familiar and deeply strange. I regard the ‘second person’ as a special case of narrative ‘person’ that, at its most fluid, can produce an experience of reading quite unlike that of reading traditional ‘first-‘ and ‘third-person’ narrative. Essentially, this unique experience comes about because Protean-‘you’ neglects to constitute the stable modes of subjectivity that readers expect to find within narrative textuality. These stable modes of subjectivity, modelled on what I will refer to as Cartesianism’s hegemonic notion of the self, have been thoroughly formalised and naturalised within the practices of ‘first-‘ and ‘third-person’ narrative. The Protean-‘you’ form of ‘second-person’ narrative, conversely, is a mode of narrative discourse that puts readers in a place of doubt and uncertainty, its unsettling equivocations forcefully disrupting accustomed, mimetic explanations of narrative and denying us access to the foundational, authorising subject of classical Cartesian thought. Rather than founding a notion of ‘second-person’ narrative and narrative ‘person’ generally on Cartesianism's ‘self-ish’ logic of unified, privatised identity, I turn to C.S, Peirce's notion of the semiotic self and to developments in post-structuralist thought. Essentially, the conception of subjectivity underpinning my arguments is Peirce's proposition that the self is to be conceived of not as a cogito, but as a sign by which the conscious entity knows itself. It is a sign, moreover, that is constantly being re-read, reinterpreted, so that identity is never self-complete. This reconception of subjectivity is necessary because 1 will argue that the effects of Protean-‘you’ arise in some part from a tension between Cartesianism's hegemony and what philosophical pragmatism and post-structuralism glimpse as the actual condition of the human subject—the subject as dispersed and contingent rather than unified and authoritative. Most discussions of ‘second-person’ narrative conceive of the mode in terms of implicit communicative relations, in some measure instituting Cartesianism's notion of the intentionalist self at the centre of literary meaning. I contrast the paradigmatic address model that arises from this conception against a model that approaches the analysis of ‘second-person’ narrative modality in terms of a referential function, that is, in terms of the object or objects referred to deictically by the ‘second-person’ pronoun. Two principal functions of ‘second-person’ textuality are identified and discussed at length. The first is generalisation, which is rarely dissipated altogether, a situation that contributes to the ambiguities of the pronoun's reference in much ‘second-person’ fiction. The second principal function is that of address, that is, the allocutionary function. Clearly, although stories that continually refer to a ‘you’ can seem quite baffling and unnatural, not all ‘second-person’ narratives unsettle the reader. In order to make the ‘second person's’ outlandish narratives knowable and stable, we bring to bear on them in our habits of reading whatever hermeneutic frames, whatever interpretive keys, come to hand, including a large number of unexceptional forms of literary and ‘natural’ discourse that employ the ‘second-person’ pronoun. These forms include letter writing and internal dialogue (i.e., talking to one's self), the language of the courtroom, the travelogue, the maxim, and so on. In looking at the ways in which the radicalising potentials of ‘second-person’ discourse are contained or recuperated, I focus on issues of vraisemblance and mimesis. Vraisemblance can be described as the ‘system of conventions and expectations which rests on/reinforces that more general system of ‘mutual knowledge’ produced within a community for the realisation and maintenance of a whole social world’. All of the forms of the vraisemblable are already instituted within social, cultural relations, so that what vraisemblance describes is the way we fit the inscriptions we read-that is, the way in which we naturalise what we read-into those given cultural and social forms. I also look at the conventionalising and naturalising work done by notions of mimesis in explaining relations between the world, our being in it, and texts, proposing that mimesis provides a principle buttress by which the good standing of the metaphor of ‘person’ is preserved in traditional and pre-critical modes of analysis. Indeed, the critic’s recourse to ‘person’ is in some measure always an engagement with mimesis. Any discussion that maintains that mimesis is in some way productive of meaning-which this thesis in fact does-must identify mimesis as a merely conventional category within practices of reading and semiosis more generally, and at the very least remove that term from its traditional position of transparent primacy and authority. Some of the most interesting and insightful arguments about ‘second-person’ narrative propose that the ‘second person’s’ most striking effects derive from the constitution of an ‘intersubjective’ experience of reading in which the subject positions of the ‘you’-protagonist, reader-narratee and narrator are combined into a fluid and indeterminate multiple subjectivity. Notions of intersubjectivity frequently position themselves as liberating the reader from Cartesianism's fixed, authoritative modes of subjectivity, Frequently, however, they tend implicitly to reinstate Cartesianism's notion of the self at the centre of textual practice and subjectivity. I look at Daniel Gunn's novel ‘Almost You’, at length in this context, illustrating the constant overdetermination of the ‘you’ and the novel's narrating voice, and demonstrating that this overdetermination leaves the origin of the narrative discourse, the identity of the narrator, and the ontological nature of both principal protagonists utterly ambiguous. The fluidity and ambiguity of Protean-‘you’ in ‘Almost You’ is discussed in terms of ‘second-person’ intersubjectivity, but with a view to demonstrating the indebtedness by the notion of intersubjectivity to Cartesianism's hegemony of ‘person’. I then turn to a discussion of what might be a more ‘old fashioned’ if perhaps ultimately more far-reaching approach to the ‘second person’s’ often startling ambiguities. This is Keats's notion of negative capability, a capacity or quality in which a person ‘is capable of being in uncertainties, Mysteries, doubts, without any irritable reaching after fact and reason.’ I suggest that Protean-‘you’ texts will license all of the readings of ambiguity and fluidity proposed in my discussion of ‘Almost You’, but conclude that the instances of indeterminacy illustrate no more than that: the fluidity and deep ambiguity, and thus, finally, the lack of coherence, of Protean-‘you’ discourse. This has particular implications for how we are to consider readers’ experiences of narrative texts. More fundamentally, it has implications for how we are to consider readers as subjects. I suggest that unstable, ambiguous instances of ‘second-person’ narrative can tear the complex and systematic embroidery of ideological suture that unifies Cretinism’s experience or sense of subjectivity, leaving the reader in a condition of epistemological and ontological havoc. I go on to argue that much of the deeply unsettling effect of Protean-‘you’ discourse anises because its utterances explicitly gesture towards Cretinism’s notion of self. Protean-‘you’ involves a sense of address that is much more pronounced than we are accustomed to facing when reading literary narrative, alerting us to the presence of inscribed anthropomorphic subjects. At the very same time, protean-‘you’ leaves its inscribed subjects indeterminate, ambiguous. This conflict generates a tension between the anticipation of the emergence of speaking and listening selves and our inability to find them. I go on to propose that Protean-‘you’ narrative's lack of coherence is also to be understood as the condition of narrative actuality generally, but a condition that is vigorously mediated against by dominant practices of reading and writing, hocusing my discussion in this respect on the issue of narrative ‘person,’ I argue that narrative ‘person’ is constituted within texts as an apparent unity, but that it is in fact, produced as unitary solely within the practice of making sense, that is, Within our habits of reading, and so is never finally unified. I propose that this is the case for ‘first-‘ and ‘third-person’ modes no less than for the ‘second.’ Where ‘second-person’ narrative at its most radical and Protean differs from conventional ‘first-‘ and ‘third-person’ narratives is the degree to which each has been circumscribed by practices of tantalization, containment and limit, and, in particular, Cretinism’s hegemony of ‘person.’ It may be that the most significant insights ‘second-person’ narrative has to offer are to be found within its capacity to reveal to the engaged reader the underlying condition of narrative discourse, and more generally, its capacity to reveal the actual condition of the human subject-a condition in which, exactly like its textual corollary of narrative ‘person,’ the self is glimpsed as thoroughly dispersed and contingent.

Function-based approach to mixed haptic effects rendering

Commonly, surface and solid haptic effects are defined in such a way that they hardly can be rendered together. We propose a method for defining mixed haptic effects including surface, solid, and force fields. These haptic effects can be applied to virtual scenes containing various objects, including polygon meshes, point clouds, impostors, and layered textures, voxel models as well as function-based shapes. Accordingly, we propose a way how to identify location of the haptic tool in such virtual scenes as well as consistently and seamlessly determine haptic effects when the haptic tool moves in the scenes with objects having different sizes, locations, and mutual penetrations. To provide for an efficient and flexible rendering of haptic effects, we propose to concurrently use explicit, implicit and parametric functions, and algorithmic procedures.

Discovering implicit criteria preferences reflected in tourism journal ranking lists using the Choquet Integral

Variations between journal rankings may cause confusion. As such, prior attempts were made to compare and evaluate journal ranking criteria for obtaining insightful knowledge on how different research communities have ranked journals. However, existing approaches are unable to model the journal ranking process closely enough as they are incapable of considering the relationship between multiple criteria simultaneously. In this paper, we address the challenges by introducing the Choquet Integral (CI) for evaluating journal ranking criteria. The new approach is able to account for interactions between criteria in relation to overall ranking score, using a fuzzy measure in its computation. Its properties, the Shapley value and the Interaction index, allow for good representations of importance and interactions between criteria. We demonstrate the efficiency of the CI through a case study of journal ranking lists in tourism and service journals.