• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 253
  • 186
  • 28
  • 26
  • 20
  • 12
  • 11
  • 6
  • 4
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 703
  • 504
  • 221
  • 210
  • 171
  • 122
  • 115
  • 100
  • 88
  • 80
  • 71
  • 66
  • 63
  • 62
  • 62
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
161

Voices From a Marginalized Population: Life Histories of Individuals With Physical Impairments

Marsh, James Peter 21 January 2005 (has links)
Individuals with physical impairments have been marginalized and discriminated against since the social identification of these individuals occurred as a sub-group within society. While much has been done to resolve prejudice against individuals with physical impairments, more needs to be done to decrease, or at least deter, discrimination and prejudice against individuals who have been marginalized. The purpose of this study is to give four individuals with physical impairments the opportunity to tell their stories. Through the telling of these stories, I believe others can identify with these individuals, and thereby, help decrease discrimination against individuals with physical impairments. Life history has been shown to be an effective method to study individuals with impairments. In order to facilitate understanding of what it is like to be an individual with a physical impairment, four individuals with physical impairments shared their life histories. Research questions include: How do these individuals with physical impairments understand and give meaning to their lived experiences? and How do participants in this study who have congenital disabilities differ from those who have acquired disabilities in the ways they understand and give meaning to their lives? The research questions and parameters of interest are intended to develop and share what it is like to be an individual with a physical impairment. The researcher has known each of the participants for at least ten years. The participants include a 33 year old male with a congenital disability who is white, a 32 year old female who acquired a disability 12 years ago and who is African American, and a married couple who are 62 and 63 years old, one with a congenital disability, the other acquired a disability when she was 14 years old. The researcher shares his responses and reflections, thereby becoming the fifth participant in the study. Because this type of research depends upon verisimilitude, the responses to the research questions are presented for each individual. Each participant defines areas of his or her life that best defines how that person constructs his or her identity and what part the physical impairment plays in that definition. The participants feel that there are some differences between individuals with congenital physical impairments and those with acquired physical impairments. The participants relate that individuals with acquired physical impairments have greater access to funds and equipment based on their perception of how funding agencies provide services and equipment to individuals with physical impairments. The participants also feel that there is a greater stigma associated with having a congenital physical impairment compared to having an acquired physical impairment. Recommendations for future research are offered.
162

Design and Testing of a Marsupial/Companion Robot Prototype for a Powered Wheelchair

Konda, Sashi Kumar 27 October 2004 (has links)
Individuals with disabilities yearn for an increased level of independence, seeking to supplement their missing function(s) and to carry on with their lives with minimal or no assistance from another person. A review of the existing assistive-care products has revealed that many of the defects in these devices, particularly in wheelchair-mounted robots, can be alleviated. Surveys have also identified tasks that users would like to perform by themselves, but are constrained from doing so by using currently available devices. An attempt has been made here to try to resolve these issues by developing a prototype of a marsupial robot that can dock into the powered wheelchair that is used for manipulation purposes. The primary function of this system is to assist the user in his/her daily tasks such as pick-up small objects and place them as per the user's commands, push to open/close doors and remove obstacles from the wheelchair path. It is with the objective of providing an enhanced quality of life to a person with impairment(s) that a proposal for a simple, safe and inexpensive approach to assist him/her in performing an activity is made here.
163

A P300-Based Brain-Computer Interface: Testing an Alternative Method of Communication

Sellers, Eric W 17 November 2004 (has links)
The current study evaluates the effectiveness of a Brain-Computer Interface (BCI) system that operates by detecting a P300 elicited by one of four randomly presented stimuli (i.e., YES, NO, PASS, END). Two groups of participants were tested. The first group included three ALS patients that varied in degree of disability, but all retained the ability to communicate; the second group included three Non-ALS controls. Each participant participated in ten experimental sessions during a period of approximately 6 weeks. Sessions were conducted either at the participant's home or in the lab. During each run the participant's task was to attend to one stimulus and disregard the other three. Stimuli were presented auditorily, visually, or in both modes. Additionally, on each run, the experimenter would either tell the participant which stimulus to focus on, or ask the participant a question and the participant would focus on the correct "YES/NO" answer to the question. Overall, for each participant, the ERPs elicited by the target stimuli could be discriminated from the non-target stimuli; however, less variability was observed in the Non-ALS group. Comparing across sessions, the within session variability was lower than across session variability. In addition, waveform morphology varied as a function of the presentation mode, but not in a similar pattern for each participant. Offline and simulated online classification algorithms conducted using step-wise discriminant analysis produced results suggesting the potential for online classification performance at levels acceptable for communication. Future investigations will begin to focus on testing online classification performance with real-time feedback, and continuing to examine stimulus properties to determine how to maximize P300 amplitude for individual users.
164

A Brain Robot Interface for Autonomous Activities of Daily Living Tasks

Pathirage, Don Indika Upashantha 15 July 2014 (has links)
There have been substantial improvements in the area of rehabilitation robotics in the recent past. However, these advances are inaccessible to a large number of people with disabilities who are in most need of such assistance. This group includes people who are in a severely paralyzed state, that they are completely "locked-in" in their own bodies. Such persons usually retain full cognitive abilities, but have no voluntary muscle control. For these persons, a Brain Computer Interface (BCI) is often the only way to communicate with the outside world and/or control an assistive device. One major drawback to BCI devices is their low information transfer rate, which can take as long as 30 seconds to select a single command. This can result in mental fatigue to the user, specially if it necessary to make multiple selections over the BCI to complete a single task. Therefore, P300 based BCI control is not efficient for controlling a assistive robotic device such as a robotic arm. To address this shortcoming, a novel vision based Brain Robot Interface (BRI) is presented in this thesis. This visual user interface allows for selecting an object from an unstructured environment and then performing an action on the selected object using a robotic arm mounted to a power wheelchair. As issuing commands through BCI is slow, this system was designed to allow a user to perform a complete task via a BCI using an autonomous robotic system while issuing as few commands as possible. Furthermore, the new visual interface allows the user to perform the task without losing concentration on the stimuli or the task. In our interface, a scene image is captured by a camera mounted on the wheelchair, from which, a dynamically sized non-uniform stimulus grid is created using edge information. Dynamically sized grids improve object selection efficiency. Oddball paradigm and P300 Event Related Potentials (ERP) are used to select stimuli, where the stimuli being each cell in the grid. Once selected, object segmentation and matching is used to identify the object. Then the user, using BRI, chooses an action to be performed on the object by the wheelchair mounted robotic arm (WMRA). Tests on 8 healthy human subjects validated the functionality of the system. An average accuracy of 85.56% was achieved for stimuli selection over all subjects. With the proposed system, it took the users an average of 5 commands to perform a task on an object. The system will eventually be useful for completely paralyzed or locked-in patients for performing activities of daily living (ADL) tasks.
165

Interaction décisionnelle homme-robot: la planification de tâches au service de la sociabilité du robot

Montreuil, Vincent 07 November 2008 (has links) (PDF)
Cette thèse aborde la problématique du robot assistant et plus particulièrement les aspects décisionnels qui y sont liés. Un robot assistant est amené à interargir avec des hommes ce qui impose qu'il doit intègrer dans son processus décisionnel de haut-niveau les contraintes sociales inhérentes à un comportement acceptable par son(ses) partenaire(s) humain(s). Cette thèse propose une approche permettant de décrire de manière générique diverses règles sociales qui sont introduites dans le processus de planification du robot afin d'évaluer la qualité sociale des plans solutions et de ne retenir que le(s) plus approprié(s). Cette thèse décrit également l'implémentation de cette approche sous la forme d'un planificateur de tâches appelé HATP (Human Aware Task Planner en anglais). Enfin, cette thèse propose une validation de l'approche développée grâce à un scénario de simulation et à une mise en oeuvre sur un robot réel.
166

Haptic Image Exploration

Lareau, David 12 January 2012 (has links)
The haptic exploration of 2-D images is a challenging problem in computer haptics. Research on the topic has primarily been focused on the exploration of maps and curves. This thesis describes the design and implementation of a system for the haptic exploration of photographs. The system builds on various research directions related to assistive technology, computer haptics, and image segmentation. An object-level segmentation hierarchy is generated from the source photograph to be rendered haptically as a contour image at multiple levels-of-detail. A tool for the authoring of object-level hierarchies was developed, as well as an innovative type of user interaction by region selection for accurate and efficient image segmentation. According to an objective benchmark measuring how the new method compares with other interactive image segmentation algorithms shows that our region selection interaction is a viable alternative to marker-based interaction. The hierarchy authoring tool combined with precise algorithms for image segmentation can build contour images of the quality necessary for the images to be understood by touch with our system. The system was evaluated with a user study of 24 sighted participants divided in different groups. The first part of the study had participants explore images using haptics and answer questions about them. The second part of the study asked the participants to identify images visually after haptic exploration. Results show that using a segmentation hierarchy supporting multiple levels-of-detail of the same image is beneficial to haptic exploration. As the system gains maturity, it is our goal to make it available to blind users.
167

Access via a Multiple Camera Tongue Switch for Children with Severe Spastic Quadriplegic Cerebral Palsy

Leung, Brian 02 March 2011 (has links)
Access technologies facilitate novel and alternative methods for individuals with disabilities to interact with their environment. Finding suitable access solutions for children with severe spastic quadriplegic cerebral palsy can be difficult because of their poor motor control and targeting abilities due to spasticity at the limbs, neck, and head. In this research a multiple camera tongue switch was developed for a 7 year-old case study participant with severe spastic quadriplegia. Remotely via video, this system reacts to tongue protrusions as cues for single-switch access. Having multiple cameras mitigates targeting problems with the head that conventional single camera systems would present. Results of a usability experiment with the participant show that good sensitivity (82%) and specificity (80%) can be achieved with a non-contact tongue protrusion access modality for a user with spastic quadriplegia. Moreover, the experiment verified that the extra cameras improve utility of video-based access technologies for the target population.
168

Development of an Anti-collision and Navigation System for Powered Wheelchairs

How, Tuck-Voon 01 January 2011 (has links)
Powered wheelchairs offer a means of independent mobility for older adults who are unable to walk and cannot propel a manual wheelchair. Unfortunately, cognitively impaired older adults may be denied this means of independent mobility. There is concern that these adults are unable to drive a powered wheelchair safely or properly. Intelligent wheelchairs offer an approach to address this problem. This research outlines the development and evaluation of an Intelligent Wheelchair System (IWS) that is proposed to make powered wheelchairs safer and easier to use for cognitively impaired older adults. The IWS has anti-collision and navigation functions. Hardware results show a 1000% increase in computational speed compared to the previous IWS. Clinical results with dementia patients show that the IWS has the potential to increase safety by reducing frontal collisions, and by promoting safe completion of movement tasks. Usability of the system may be an issue.
169

Development of an Anti-collision and Navigation System for Powered Wheelchairs

How, Tuck-Voon 01 January 2011 (has links)
Powered wheelchairs offer a means of independent mobility for older adults who are unable to walk and cannot propel a manual wheelchair. Unfortunately, cognitively impaired older adults may be denied this means of independent mobility. There is concern that these adults are unable to drive a powered wheelchair safely or properly. Intelligent wheelchairs offer an approach to address this problem. This research outlines the development and evaluation of an Intelligent Wheelchair System (IWS) that is proposed to make powered wheelchairs safer and easier to use for cognitively impaired older adults. The IWS has anti-collision and navigation functions. Hardware results show a 1000% increase in computational speed compared to the previous IWS. Clinical results with dementia patients show that the IWS has the potential to increase safety by reducing frontal collisions, and by promoting safe completion of movement tasks. Usability of the system may be an issue.
170

Virtual Dynamic Tunnel: A Target-Agnostic Assistive User Interface Algorithm for Head-Operated Input Devices

Blackmon, Ferrol R 11 November 2010 (has links)
Today the effective use of computers (e.g. those with Internet browsers and graphical interfaces) involves the use of some sort of cursor control like what a mouse provides. However, a standard mouse is not always the best option for all users. There are currently many devices available to provide alternative computer access. These devices may be divided into categories: brain-computer interfaces (BCI), mouth-based controls, camera-based controls, and head-tilt controls. There is no single solution as each device and application has to be tailored to each user's unique preferences and abilities. Furthermore, each device category has certain strengths and weaknesses that need to be considered when making an effective match between a user and a device. One problem that remains is that these alternative input devices do not perform as well when compared to standard mouse devices. To help with this, assistive user interface techniques can be employed. While research shows that these techniques help, most require that modifications be made to the user interfaces or that a user's intended target be known beforehand by the host computer. In this research, a novel target-agnostic assistive user interface algorithm intended to improve usage performance for both head-operated and standard mouse devices is designed, implemented (as a mouse device driver and in host computer software) and experimentally evaluated. In addition, a new wireless head-operated input device requiring no special host computer hardware, is designed, built and evaluated. It was found that the Virtual Dynamic Tunnel algorithm improved performance for a standard mouse in straight tunnel trials and that nearly 60% of users would be willing to use the head-tilt mouse as a hands-free option for cursor control.

Page generated in 0.0771 seconds