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Visual Display (visual + display)

Distribution by Scientific Domains

Medical Sciences	36%

Selected Abstracts

Towards closing the analysis gap: Visual generation of decision supporting schemes from raw data

COMPUTER GRAPHICS FORUM, Issue 3 2008
T. May
Abstract The derivation, manipulation and verification of analytical models from raw data is a process which requires a transformation of information across different levels of abstraction. We introduce a concept for the coupling of data classification and interactive visualization in order to make this transformation visible and steerable for the human user. Data classification techniques generate mappings that formally group data items into categories. Interactive visualization includes the user into an iterative refinement process. The user identifies and selects interesting patterns to define these categories. The following step is the transformation of a visible pattern into the formal definition of a classifier. In the last step the classifier is transformed back into a pattern that is blended with the original data in the same visual display. Our approach allows in intuitive assessment of a formal classifier and its model, the detection of outliers and the handling of noisy data using visual pattern-matching. We instantiated the concept using decision trees for classification and KVMaps as the visualization technique. The generation of a classifier from visual patterns and its verification is transformed from a cognitive to a mostly pre-cognitive task. [source]

Sound induces perceptual reorganization of an ambiguous motion display in human infants

DEVELOPMENTAL SCIENCE, Issue 3 2003
Christian Scheier
Adults who watch an ambiguous visual event consisting of two identical objects moving toward, through, and away from each other and hear a brief sound when the objects overlap report seeing visual bouncing. We conducted three experiments in which we used the habituation/test method to determine whether these illusory effects might emerge early in development. In Experiments 1 and 3 we tested 4-, 6- and 8-month-old infants' discrimination between an ambiguous visual display presented together with a sound synchronized with the objects' spatial coincidence and the identical visual display presented together with a sound no longer synchronized with coincidence. Consistent with illusory perception, the 6- and 8-month-old, but not the 4-month-old, infants responded to these events as different. In Experiment 2 infants were habituated to the ambiguous visual display together with a sound synchronized with the objects' coincidence and tested with a physically bouncing object accompanied by the sound at the bounce. Consistent with illusory perception again, infants treated these two events as equivalent by not exhibiting response recovery. The developmental emergence of this intersensory illusion at 6 months of age is hypothesized to reflect developmental changes in object knowledge and attentional mechanisms. [source]

How the parallel channels of the retina contribute to depth processing

EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 5 2007
Peter H. Schiller
Abstract Reconstructing the third dimension in the visual scene from the two dimensional images that impinge on the retinal surface is one of the major tasks of the visual system. We have devised a visual display that makes it possible to study stereoscopic depth cues and motion parallax cues separately or in concert using rhesus macaques. By varying the spatial frequency of the display and its luminance and chrominance, it is possible to selectively activate channels that originate in the primate retina. Our results show that (i) the parasol system plays a central role in processing motion parallax cues; (ii) the midget system plays a central role in stereoscopic depth perception at high spatial frequencies, and (iii) red/green colour selective neurons can effectively process both cues but blue/yellow neurons cannot do so. [source]

Dissociation between top-down attentional control and the time course of visual attention as measured by attentional dwell time in patients with mild cognitive impairment

EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 2 2003
Richard J. Perry
Abstract Studies of the time course of visual attention have identified a temporary functional blindness to the second of sequentially presented stimuli in that the attentional cost of attending to one visual stimulus may lead to impairments in identifying a second stimulus presented within 500 ms of the first. This phenomenon is known as the attentional blink or attentional dwell time. The neural correlates of the attentional blink and its relationship to mechanisms that control attention are unknown. To examine this relationship we tested healthy controls and subjects in the preclinical stage of Alzheimer's disease, known as mild cognitive impairment (MCI), on a paradigm which affords quantification of both the attentional blink and the top-down control of attention. When subjects were asked to identify both a number and a letter that were rapidly and sequentially presented on a visual display, the detrimental effect that identifying the first stimulus had on the ability to identify the second served as a measure of the attentional blink. When asked to identify only one of the two stimuli, the ability to ignore the first stimulus was a function of their top-down attentional control. The MCI subjects demonstrated a normal attentional dwell time but in contrast they showed impaired top-down attentional control within the same paradigm. This dissociation suggests that these two aspects of visual attention are subserved by different neural systems. The possible neural correlates of these two attentional functions are discussed. [source]

Ground Water Quality Assessment Using Multi-Rectangular Diagrams

GROUND WATER, Issue 6 2003
Niaz Ahmad
A new graphical technique is proposed here for classifying chemical analyses of ground water. In this technique, a diagram is constructed using rectangular coordinates. The new diagram, called a multi-rectangular diagram (MRD), uses adjacent multi-rectangles in which each rectangle represents a specific ground water type. This new diagram has the capability to accommodate a large number of data sets. MRDs have been used to classify chemical analyses of ground water in the Chaj Doab area of Pakistan to illustrate this new approach. Using this graphical method, the differentiated ground water types are calcium bicarbonate, magnesium bicarbonate, sodium bicarbonate, and sodium sulfate. Sodium bicarbonate emerges as the most abundant ground water type. MRDs also offer a visual display of the Chebotarev sequence of ground water quality evolution. [source]

The effects of graphical overviews on knowledge acquisition in hypertext

JOURNAL OF COMPUTER ASSISTED LEARNING, Issue 2 2002
T. De Jong
Abstract A central aspect of designing hypertext for learning concerns the structure of the information in the hypertext and the view the learner is offered of this structure. In this study, a hypertext environment was enhanced with a graphical overview that represented the basic, inherent, structure of the domain and the layout was designed in such a way that learners were unobtrusively encouraged to follow a sequence of exploration that followed the domain structure. This so-called ,visual' lay-out was compared with two lay-outs that presented randomly positioned nodes. One of these two lay-outs contained hints (using ,highlighting') to stimulate learners to follow a domain related exploration similar to the one incorporated in the visual lay-out. The other (,control') lay-out did not provide such hints. Results showed that participants from both the ,visual' and the ,hints' conditions demonstrated a more domain-related exploration pattern than participants from the ,control' condition. Participants in the ,visual' lay-out did not show a better recall of the content of the nodes as such, but showed a significantly better acquisition of knowledge of structure than participants from the other two conditions. These data indicate that a visual display conveys knowledge in its own right and that knowledge gained does not depend on the exploration route followed in the hypertext material. [source]

Shared decision making observed in clinical practice: visual displays of communication sequence and patterns

JOURNAL OF EVALUATION IN CLINICAL PRACTICE, Issue 2 2001
Glyn Elwyn BA MSc FRCGP
Abstract The aim of the study was to examine the communication strategies of general practitioners attempting to involve patients in treatment or management decisions. This empirical data was then compared with theoretical ,competences' derived for ,shared decision making'. The subjects were four general practitioners, who taped conducted consultations with the specific intent of involving patients in the decision-making process. The consultations were transcribed, coded into skill categorizations and presented as visual display using a specifically devised sequential banding method. The empirical data from these purposively selected consultation from clinicians who are experienced in shared decision making did not match suggested theoretical frameworks. The views of patients about treatment possibilities and their preferred role in decision making were not explored. The interactions were initiated by a problem-defining phase, statements of ,equipoise' consistently appeared and the portrayal of option information was often intermingled with opportunities to allow patients to question and reflect. A decision-making stage occurred consistently after approximately 80% of the total consultation duration and arrangements were consistently made for follow-up and review. Eight of the 10 consultations took more than 11 min , these specific consultations were characterized by significant proportions of time provided for information exchange and patient interaction. The results demonstrate that some theoretical competences are not distinguishable in practice and other stages, not previously described, such as the ,portrayal of equipoise', are observed. The suggested ideal of a shared decision-making interaction will either require more time than currently allocated, or alternative strategies to enable information exchange outside the consultation. [source]

Graphic and haptic modelling of the oesophagus for VR-based medical simulation

THE INTERNATIONAL JOURNAL OF MEDICAL ROBOTICS AND COMPUTER ASSISTED SURGERY, Issue 3 2009
Changmok Choi
Abstract Background Medical simulators with vision and haptic feedback have been applied to many medical procedures in recent years, due to their safe and repetitive nature for training. Among the many technical components of the simulators, realistic and interactive organ modelling stands out as a key issue for judging the fidelity of the simulation. This paper describes the modelling of an oesophagus for a real-time laparoscopic surgical simulator. Methods For realistic simulation, organ deformation and tissue cutting in the oesophagus are implemented with geometric organ models segmented from the Visible Human Dataset. The tissue mechanical parameters were obtained from in vivo animal experiments and integrated with graphic and haptic devices into the laparoscopic surgical simulation system inside an abdominal mannequin. Results This platform can be used to demonstrate deformation and incision of the oesophagus by surgical instruments, where the user can haptically interact with the virtual soft tissues and simultaneously see the corresponding organ deformation on the visual display. Conclusions Current laparoscopic surgical training has been transformed from the traditional apprenticeship model to simulation-based methods. The outcome of the model could replace conventional training systems and could be useful in effectively transferring surgical skills to novice surgeons. Copyright © 2009 John Wiley & Sons, Ltd. [source]

Community-based Participatory Research: Development of an Emergency Department,based Youth Violence Intervention Using Concept Mapping

ACADEMIC EMERGENCY MEDICINE, Issue 8 2010
Carolyn E. Snider MD, FRCPC
ACADEMIC EMERGENCY MEDICINE 2010; 17:1,9 © 2010 by the Society for Academic Emergency Medicine Abstract Objectives:, Emergency departments (EDs) see a high number of youths injured by violence. In Ontario, the most common cause of injury for youths visiting EDs is assault. Secondary prevention strategies using the teachable moment (i.e., events that can lead individuals to make positive changes in their lives) are ideal for use by clinicians. An opportunity exists to take advantage of the teachable moment in the ED in an effort to prevent future occurrences of injury in at-risk youths. However, little is known about perceptions of youths, parents, and community organizations about such interventions in EDs. The aims of this study were to engage youths, parents, and frontline community workers in conceptualizing a hospital-based violence prevention intervention and to identify outcomes relevant to the community. Methods:, Concept mapping is an innovative, mixed-method research approach. It combines structured qualitative processes such as brainstorming and group sorting, with various statistical analyses such as multidimensional scaling and hierarchical clustering, to develop a conceptual framework, and allows for an objective presentation of qualitative data. Concept mapping involves multiple structured steps: 1) brainstorming, 2) sorting, 3) rating, and 4) interpretation. For this study, the first three steps occurred online, and the fourth step occurred during a community meeting. Results:, Over 90 participants were involved, including youths, parents, and community youth workers. A two-dimensional point map was created and clusters formed to create a visual display of participant ideas on an ED-based youth violence prevention intervention. Issues related to youth violence prevention that were rated of highest importance and most realistic for hospital involvement included mentorship, the development of youth support groups in the hospital, training doctors and nurses to ask questions about the violent event, and treating youth with respect. Small-group discussions on the various clusters developed job descriptions, a list of essential services, and suggestions on ways to create a more youth-friendly environment in the hospital. A large-group discussion revealed outcomes that participants felt should be measured to determine the success of an intervention program. Conclusions:, This study has been the springboard for the development of an ED-based youth violence intervention that is supported by the community and affected youth. Using information generated by youth that is grounded in their experience through participatory research methods is feasible for the development of successful and meaningful youth violence prevention interventions. [source]

Shared decision making observed in clinical practice: visual displays of communication sequence and patterns

Following the Nyinkka: Relations of Respect and Obligations to Act in the Collaborative Work of Aboriginal Cultural Centers

MUSEUM ANTHROPOLOGY, Issue 2 2007
Kimberly Christen
In July 2003 the Warumungu Aboriginal community opened the Nyinkka Nyunyu Art and Culture Centre in Tennant Creek, Northern Territory, Australia. Nyinkka Nyunyu is a Warumungu community center, museum, and tourist destination. As such it embodies the eclectic and practical modalities of Aboriginal business. This article examines the practices of Aboriginal representation and self-determination through the behind-the-scenes work of community consultation, collaboration, and culturemaking. Looking to existing social relations and systems of obligation, the Warumungu community's production of the visual displays for the Centre demonstrates the interdependent networks forged out of a colonial history of displacement and a present trajectory of alliance-building. [source]