+publisher:"University of Houston" +contributor:("Contreras-Vidal, Jose L.")

University of Houston

1. Agashe, Harshavardhan A. Noninvasive Neuroprosthetic Control of Grasping by Amputees.

Degree: PhD, Electrical Engineering, 2014, University of Houston

► Smooth coordination and fine temporal control of muscles by the brain allows us to effortlessly pre-shape our hand to grasp different objects. Correlates of motor… (more)

▼ Smooth coordination and fine temporal control of muscles by the brain allows us to effortlessly pre-shape our hand to grasp different objects. Correlates of motor control for grasping have been found across wide-spread cortical areas, with diverse signal features. These signals have been harnessed by implanting intracortical electrodes and used to control the motion of robotic hands by tetraplegics, using algorithms called brain-machine interfaces (BMIs). Signatures of motor control signal encoding mechanisms of the brain in macro-scale signals such as electroencephalography (EEG) are unknown, and could potentially be used to develop noninvasive brain-machine interfaces. Here we show that a) low frequency (0.1 – 1 Hz) time domain EEG contains information about grasp pre-shaping in able-bodies individuals, and b) This information can be used to control pre-shaping motion of a robotic hand by amputees. In the first study, we recorded simultaneous EEG and hand kinematics as 5 able-bodies individuals grasped various objects. Linear decoders using low delta band EEG amplitudes accurately predicted hand pre-shaping kinematics during grasping. Correlation coefficient between predicted and actual kinematics was r = 0.59 ± 0.04, 0.47 ± 0.06 and 0.32 ± 0.05 for the first 3 synergies. In the second study, two transradial amputees (A1 and A2) controlled a prosthetic hand to grasp two objects using a closed-loop BMI with low delta band EEG. This study was conducted longitudinally in 12 sessions spread over 38 days. A1 achieved a 63% success rate, with 11 sessions significantly above chance. A2 achieved a 32% success rate, with 2 sessions significantly above chance. Previous methods of EEG-based BMIs used frequency domain features, and were thought to have a low signal-to-noise ratio making them unsuitable for control of dexterous tasks like grasping. Our results demonstrate that time-domain EEG contains information about grasp pre-shaping, which can be harnessed for neuroprosthetic control. Advisors/Committee Members: Vidal%2C%20Jose%20L.%22%29&pagesize-30">Contreras-Vidal, Jose L. (advisor), Ogmen, Haluk (committee member), Sheth, Bhavin R. (committee member), Dragomir, Andrei (committee member), Cipriani, Christian (committee member).

Subjects/Keywords: Brain-machine interface; Electroencephalography (EEG); EEG; Upper limb; Neuroprosthetic

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APA (6^th Edition):

Agashe, H. A. (2014). Noninvasive Neuroprosthetic Control of Grasping by Amputees. (Doctoral Dissertation). University of Houston. Retrieved from http://hdl.handle.net/10657/1663

Chicago Manual of Style (16^th Edition):

Agashe, Harshavardhan A. “Noninvasive Neuroprosthetic Control of Grasping by Amputees.” 2014. Doctoral Dissertation, University of Houston. Accessed January 20, 2021. http://hdl.handle.net/10657/1663.

MLA Handbook (7^th Edition):

Agashe, Harshavardhan A. “Noninvasive Neuroprosthetic Control of Grasping by Amputees.” 2014. Web. 20 Jan 2021.

Vancouver:

Agashe HA. Noninvasive Neuroprosthetic Control of Grasping by Amputees. [Internet] [Doctoral dissertation]. University of Houston; 2014. [cited 2021 Jan 20]. Available from: http://hdl.handle.net/10657/1663.

Council of Science Editors:

Agashe HA. Noninvasive Neuroprosthetic Control of Grasping by Amputees. [Doctoral Dissertation]. University of Houston; 2014. Available from: http://hdl.handle.net/10657/1663

University of Houston

2. -0861-902X. Cortical Control of Human Upright Stance.

Degree: PhD, Kinesiology, 2016, University of Houston

URL: http://hdl.handle.net/10657/3254

► This dissertation examined, for the first time, differences between young and elderly volunteers in cortical representations of human posture control during (1) quiet stance with… (more)

▼ This dissertation examined, for the first time, differences between young and elderly volunteers in cortical representations of human posture control during (1) quiet stance with normal and altered sensory stimulation, (2) biomechanical perturbations, and (3) dual tasking. The primary focus of the first part was to monitor changes in cortical activity when unexpectedly altering the sensory conditions of upright stance, such as switching from stable (eyes open, fixed support surface) to less-stable (eyes closed, sway-referenced support surface) conditions (experiment 1). Our results demonstrate increased cortical activations in delta (0.2-4Hz) and gamma (30-50 Hz) oscillations, primarily over central-frontal, central and central parietal cortices during challenging postural conditions. While increased delta rhythms were observed in both groups during challenging sensory conditions, elderly individuals also showed increased gamma band activity over sensorimotor and parietal cortices, when compared to the younger group. Correlation analyses also suggest that increased cerebral activity became more relevant to the control of Center of Mass dynamics when upright stance was threatened, especially in the elderly group. The second part studied compensatory postural responses to unexpected perturbations while simultaneously recording Electroencephalography, Electromyography, and Center of Mass dynamics (experiment 2). Our results also suggest that, rather than motor system malfunctioning, impairments in perceptual processing of sensory afferences forms the basis of prolonged postural responses to perturbed stance conditions in non-faller older adults. In general, our results are not only consistent with previous reports suggesting involvement of cerebral cortices in human upright stance control, but also extend them by showing ageing related cortical activity modulations during challenging postural tasks. The third part focused on performance changes in posture control-cognition dual tasking as well as cortical representations of these performance changes both in cognitive and posture control tasks (experiment 3). Postural and cognitive data analyses showed that elderly people had no performance deficits during single postural task conditions, but decreased cognitive performance even during challenging single cognitive tasks. Dual tasking analyses indicated that working memory impairments in the elderly group can be observed when a challenging cognitive task is performed in any postural condition, while postural control performance differences only became significant during dual tasking with challenging postural and cognitive task conditions. EEG analyses showed increased delta, theta and gamma oscillations, primarily over frontal, central-frontal, central and central-parietal cortices during challenging dual tasking conditions. While delta oscillations are more responsive to challenging postural conditions, theta rhythms are found to be changing as a function of cognitive task difficulty in both groups, with more pronounced… Advisors/Committee Members: Paloski, William H. (advisor), Layne, Charles S. (committee member), Thrasher, Timothy Adam (committee member), Vidal%2C%20Jose%20L.%22%29&pagesize-30">Contreras-Vidal, Jose L. (committee member).

Subjects/Keywords: Postural control; Balance; Elderly; EEG; EMG

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APA (6^th Edition):

-0861-902X. (2016). Cortical Control of Human Upright Stance. (Doctoral Dissertation). University of Houston. Retrieved from http://hdl.handle.net/10657/3254

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Author name may be incomplete

Chicago Manual of Style (16^th Edition):

-0861-902X. “Cortical Control of Human Upright Stance.” 2016. Doctoral Dissertation, University of Houston. Accessed January 20, 2021. http://hdl.handle.net/10657/3254.

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

MLA Handbook (7^th Edition):

-0861-902X. “Cortical Control of Human Upright Stance.” 2016. Web. 20 Jan 2021.

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

Vancouver:

-0861-902X. Cortical Control of Human Upright Stance. [Internet] [Doctoral dissertation]. University of Houston; 2016. [cited 2021 Jan 20]. Available from: http://hdl.handle.net/10657/3254.

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

Council of Science Editors:

-0861-902X. Cortical Control of Human Upright Stance. [Doctoral Dissertation]. University of Houston; 2016. Available from: http://hdl.handle.net/10657/3254

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

University of Houston

3. Noory Meshkate, Babak. Non-Retinotopic Reference Frames in Human Vision: A Dynamic Journey from Visual Chaos to Clarity.

Degree: PhD, Electrical Engineering, 2014, University of Houston

URL: http://hdl.handle.net/10657/1417

► The optics of the eye maps neighboring points in the environment to neighboring retinal photoreceptors, and these neighborhood relations, known as retinotopic organization, are qualitatively… (more)

▼ The optics of the eye maps neighboring points in the environment to neighboring retinal photoreceptors, and these neighborhood relations, known as retinotopic organization, are qualitatively preserved in early visual cortical areas. Under normal viewing conditions, due to object and observer movements in the environment, the stimuli impinging on retinotopic representations are highly dynamic and unstable. Thus, understanding ecological vision requires an understanding of how visual processes operate under these dynamic conditions. Retinotopically based theories, however, are not sufficient to explain how clarity of form is achieved in a dynamic environment. Non-retinotopic theories provide an alternative to address dynamic issues associated with purely retinotopic theories. Indeed, recent studies have indicated that many visual attributes of a stimulus are computed according to non-retinotopic reference frames. While those studies show the involvement of non-retinotopic reference frames in visual computation, the nature and spatio-temporal characteristics of these reference frames remain largely unknown. The primary goal of our research was to understand the nature and spatio-temporal properties of reference frames involved in non-retinotopic computations. Our results indicate that the effect of a dynamic non-retinotopic reference frame extends over space, creating a field within which target stimuli are localized and perceived relative to the reference. The fields of neighboring dynamic reference frames interact; static neighbors do not affect the fields of dynamic references; the non-retinotopic field effect is maximized when the target and the reference stimuli are in phase; and the field strength decreases with target-reference phase shift. The results of our visual masking experiments indicate that while masking mechanisms operate in retinotopic domain, masking effect attenuates significantly in the presence of predictable non-retinotopic reference frames. We suggest that the reference frame revealed by our studies can be better described in terms of a “field” rather than an object. Our results also indicate that the interactions between reference frames occur only when they are in motion; suggesting that the fields generated by non-retinotopic reference frames are motion-based. In conclusion, this work reveals that the dynamic nature of our visual experience should be viewed as part of the solution, rather than a problem in ecological vision. Advisors/Committee Members: Ogmen, Haluk (advisor), Breitmeyer, Bruno G. (committee member), Vidal%2C%20Jose%20L.%22%29&pagesize-30">Contreras-Vidal, Jose L. (committee member), Herzog, Michael H. (committee member), Sheth, Bhavin R. (committee member).

Subjects/Keywords: Non-retinotopic Perception; Visual Reference Frames; Dynamic Form Perception; Human Vision; Clarity of Dynamic Form; Deblurring

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Noory Meshkate, B. (2014). Non-Retinotopic Reference Frames in Human Vision: A Dynamic Journey from Visual Chaos to Clarity. (Doctoral Dissertation). University of Houston. Retrieved from http://hdl.handle.net/10657/1417

Chicago Manual of Style (16^th Edition):

Noory Meshkate, Babak. “Non-Retinotopic Reference Frames in Human Vision: A Dynamic Journey from Visual Chaos to Clarity.” 2014. Doctoral Dissertation, University of Houston. Accessed January 20, 2021. http://hdl.handle.net/10657/1417.

MLA Handbook (7^th Edition):

Noory Meshkate, Babak. “Non-Retinotopic Reference Frames in Human Vision: A Dynamic Journey from Visual Chaos to Clarity.” 2014. Web. 20 Jan 2021.

Vancouver:

Noory Meshkate B. Non-Retinotopic Reference Frames in Human Vision: A Dynamic Journey from Visual Chaos to Clarity. [Internet] [Doctoral dissertation]. University of Houston; 2014. [cited 2021 Jan 20]. Available from: http://hdl.handle.net/10657/1417.

Council of Science Editors:

Noory Meshkate B. Non-Retinotopic Reference Frames in Human Vision: A Dynamic Journey from Visual Chaos to Clarity. [Doctoral Dissertation]. University of Houston; 2014. Available from: http://hdl.handle.net/10657/1417

University of Houston

4. Agaoglu, Mehmet Naci. Nonretinotopic Reference Frames for Dynamic Form and Motion Perception.

Degree: PhD, Electrical Engineering, 2015, University of Houston

URL: http://hdl.handle.net/10657/1922

► The spatial representation of a visual scene in the early visual system is well known. The optics of the eye map the three-dimensional environment onto… (more)

▼ The spatial representation of a visual scene in the early visual system is well known. The optics of the eye map the three-dimensional environment onto two-dimensional images on the retina. These retinotopic representations are preserved in the early visual system. Retinotopic representations and processing are among the most prevalent concepts in visual neuroscience. However, it has long been known that a retinotopic representation of the stimulus is neither sufficient nor necessary for perception. Many visual processes (form and motion perception, visual search, attention, and perceptual learning) that have been thought to occur in retinotopic coordinates, have been found to operate in non-retinotopic coordinates. Based on these findings, our goal was to characterize the non-retinotopic representations and their underlying reference frames. We proposed that each retinotopic motion vector creates a perceptual reference-frame field in the retinotopic space (like an electromagnetic field), and interactions between these fields determine the selection of the effective reference frame. To test this theory, we performed a series of psychophysical experiments. We first used the slit-viewing paradigm to investigate how features of a moving object are attributed. Our results support the predictions of the non-retinotopic feature-processing hypothesis and demonstrate the ability of the visual system to operate non-retinotopically at a fine feature processing level. We then used a variant of the induced motion paradigm to investigate non-retinotopic reference frames for motion perception. We found that the effective reference frame for motion perception is non-retinotopic, and emerges from an amalgamation of motion-based, retinotopic and spatiotopic reference frames. In determining the percept, the influence of relative motion, defined by a motion-based reference frame, dominates those of retinotopic and spatiotopic motions within a finite region. Moreover, we found that different reference fields interact nonlinearly, and the way they interact depends on how motion vectors are grouped. Finally, we investigated how various spatiotemporal factors influence reference frame selection for motion perception. In line with our theory, we found that the motion-based-nearest-vector metric can fully account for all the data reported here. Taken together, these findings suggest that the brain actively constructs perceptual space by using motion-based reference frames. Advisors/Committee Members: Ogmen, Haluk (advisor), Sheth, Bhavin R. (committee member), Das, Vallabh E. (committee member), Vidal%2C%20Jose%20L.%22%29&pagesize-30">Contreras-Vidal, Jose L. (committee member), Herzog, Michael H. (committee member).

Subjects/Keywords: Reference frames; Motion perception; Retinotopy; Induced motion; Feature attribution

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Agaoglu, M. N. (2015). Nonretinotopic Reference Frames for Dynamic Form and Motion Perception. (Doctoral Dissertation). University of Houston. Retrieved from http://hdl.handle.net/10657/1922

Chicago Manual of Style (16^th Edition):

Agaoglu, Mehmet Naci. “Nonretinotopic Reference Frames for Dynamic Form and Motion Perception.” 2015. Doctoral Dissertation, University of Houston. Accessed January 20, 2021. http://hdl.handle.net/10657/1922.

MLA Handbook (7^th Edition):

Agaoglu, Mehmet Naci. “Nonretinotopic Reference Frames for Dynamic Form and Motion Perception.” 2015. Web. 20 Jan 2021.

Vancouver:

Agaoglu MN. Nonretinotopic Reference Frames for Dynamic Form and Motion Perception. [Internet] [Doctoral dissertation]. University of Houston; 2015. [cited 2021 Jan 20]. Available from: http://hdl.handle.net/10657/1922.

Council of Science Editors:

Agaoglu MN. Nonretinotopic Reference Frames for Dynamic Form and Motion Perception. [Doctoral Dissertation]. University of Houston; 2015. Available from: http://hdl.handle.net/10657/1922

University of Houston

5. Li, Ziyang 1987-. Autonomic Markers of Visual Awareness.

Degree: PhD, Electrical Engineering, 2013, University of Houston

URL: http://hdl.handle.net/10657/1217

► The mind–body problem in philosophy examines the relationship between mind and matter, and in particular, the relationship between consciousness and the brain. In order to… (more)

Subjects/Keywords: Visual awareness; Autonomic nervous system; Visual detection; Binocular rivalry; Heart rate; Heart rate variability; Pre-ejection period; Pupil

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APA (6^th Edition):

Li, Z. 1. (2013). Autonomic Markers of Visual Awareness. (Doctoral Dissertation). University of Houston. Retrieved from http://hdl.handle.net/10657/1217

Chicago Manual of Style (16^th Edition):

Li, Ziyang 1987-. “Autonomic Markers of Visual Awareness.” 2013. Doctoral Dissertation, University of Houston. Accessed January 20, 2021. http://hdl.handle.net/10657/1217.

MLA Handbook (7^th Edition):

Li, Ziyang 1987-. “Autonomic Markers of Visual Awareness.” 2013. Web. 20 Jan 2021.

Vancouver:

Li Z1. Autonomic Markers of Visual Awareness. [Internet] [Doctoral dissertation]. University of Houston; 2013. [cited 2021 Jan 20]. Available from: http://hdl.handle.net/10657/1217.

Council of Science Editors:

Li Z1. Autonomic Markers of Visual Awareness. [Doctoral Dissertation]. University of Houston; 2013. Available from: http://hdl.handle.net/10657/1217

University of Houston

6. Gonen, Fahrettin Firat 1986-. Real-Time Visual Stimulus Selection through Attentional and Decisional Processes.

Degree: PhD, Electrical Engineering, 2017, University of Houston

URL: http://hdl.handle.net/10657/4608

► Our senses continuously receive a staggering amount of information from our environment. To operate efficiently in a natural environment, our brain needs to select in… (more)

▼ Our senses continuously receive a staggering amount of information from our environment. To operate efficiently in a natural environment, our brain needs to select in real-time a subset of the information impinging on our senses. Two processes play a crucial role in real-time stimulus selection and filtering: attentional and decisional processes. The broad goal of our study was to investigate how attentional and decisional processes select visual inputs for processing. The study was divided into three parts: The first and second parts studied visual attention. The last part examined decisional processes. In the first part, we investigated the allocation of exogenous attention when perceptual groups were formed or dissolved. By varying the relative timing between the cue onset and the formation, or dissolution of perceptual groups, we sought to understand the relationship between processes organizing inputs into meaningful units (perceptual grouping) and the processes selecting from these units (attention). The time-course of attentional benefits of grouping was remarkably similar in the case of group formation and dissolution, operating within a half-second time frame. The results revealed the dynamics of how attention and grouping work in synergy during the transient period when groups form or dissolve. Attentional processes can be divided into two types: a fast reflexive process, called exogenous attention, and a slower, voluntary process, called endogenous attention. In the second part, we investigated whether endogenous and exogenous attention, operate independently or interact. The experiment demonstrated that there is an interaction between the endogenous and exogenous systems when the task was discrimination. The evidence for interaction was weak when subject’s task was detection. The interaction between the two orientation types depends on the validity of both types of orientations. When endogenous cue was valid, exogenous cue’s strength was weakened. The endogenous cue was significantly dominant than the exogenous cue. The detection tasks required significantly less time compared to discrimination tasks. In the last part, we examined information sampling by decisional processes. We tested the Small Sample Advantage (SSA) theory through predictions and found that for the low environmental contingency values, subjects preferred small sample sizes. For the remaining values, the prediction results were not conclusive. Under SSA, probability density function analysis indicates that the percentage correct can never exceed 50%. However, we carried out simulations to test whether the specific realization corresponding to our experiment could yield performance higher than 50% under SSA. Simulation results showed that indeed this was the case and produced an estimate of internal decision level used by the subjects. Advisors/Committee Members: Ogmen, Haluk (advisor), Breitmeyer, Bruno G. (committee member), Sheth, Bhavin R. (committee member), Vidal%2C%20Jose%20L.%22%29&pagesize-30">Contreras-Vidal, Jose L. (committee member), Das, Vallabh E. (committee member).

Subjects/Keywords: Attention; Perceptual grouping; Small sample advantage; Exogenous; Endogenous; Object-based attention; Space-based attention

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Gonen, F. F. 1. (2017). Real-Time Visual Stimulus Selection through Attentional and Decisional Processes. (Doctoral Dissertation). University of Houston. Retrieved from http://hdl.handle.net/10657/4608

Chicago Manual of Style (16^th Edition):

Gonen, Fahrettin Firat 1986-. “Real-Time Visual Stimulus Selection through Attentional and Decisional Processes.” 2017. Doctoral Dissertation, University of Houston. Accessed January 20, 2021. http://hdl.handle.net/10657/4608.

MLA Handbook (7^th Edition):

Gonen, Fahrettin Firat 1986-. “Real-Time Visual Stimulus Selection through Attentional and Decisional Processes.” 2017. Web. 20 Jan 2021.

Vancouver:

Gonen FF1. Real-Time Visual Stimulus Selection through Attentional and Decisional Processes. [Internet] [Doctoral dissertation]. University of Houston; 2017. [cited 2021 Jan 20]. Available from: http://hdl.handle.net/10657/4608.

Council of Science Editors:

Gonen FF1. Real-Time Visual Stimulus Selection through Attentional and Decisional Processes. [Doctoral Dissertation]. University of Houston; 2017. Available from: http://hdl.handle.net/10657/4608

7. Dettmer, Marius. VIBRATION OF THE FOOT SOLE AS AN INTERVENTION TO IMPROVE OLDER ADULTS’ POSTURAL STABILITY.

Degree: PhD, Kinesiology, 2014, University of Houston

URL: http://hdl.handle.net/10657/724

► Increase of postural instability is one of the significant issues related to aging, due to its relevance concerning risk for falls and associated impacts on… (more)

▼ Increase of postural instability is one of the significant issues related to aging, due to its relevance concerning risk for falls and associated impacts on life quality and health care costs in the U.S. Sub-threshold vibration stimulation, a passive, non-invasive countermeasure to sensorimotor decline has shown promising results related to the improvement of stability in healthy older adults and in neuropathic patients. To date, no studies have systematically investigated the potential benefits or functional limitations of this vibration intervention, and potential interactions with healthy aging processes in more demanding postural tasks. Those tasks mimic real-life situations where postural stability is challenged and actual falls might occur in older adults. The objectives of this study were to compare postural performance and control characteristics between older and younger healthy individuals, and to investigate potential changes when a vibration intervention is introduced. The effects of aging, foot sole vibration, and potential interactions were investigated in (1) a sensory conflict postural task, (2) a dual-task environment, and (3) a postural perturbation task (support surface translation). The study was performed on 10 younger adults (25.1±2.3 years) and 10 older adults (78.6±5.4 years). Vibration to the feet was delivered via custom-made rubber soles with embedded vibrotactile chips. Results indicate that (1) sensory conflict task characteristics are associated with age and vibration affects specific postural outcomes in the older group; the intervention improves postural performance when conflicting visual information is provided; (2) specific outcomes are associated with age in dual-tasking, but vibration does not affect those outcomes; (3) age is associated with specific spatial outcome measures when a postural perturbation is introduced, older adults are able to maintain stability, although they allow for more sway throughout the task; vibration does not affect performance or control characteristics. The study provides novel insight about the potential of sub-threshold vibration to the feet, and its effects on two different age groups. More research is needed to evaluate the potential of vibrating soles in more severely (balance-) impaired individuals. Advisors/Committee Members: Layne, Charles S. (advisor), Vidal%2C%20Jose%20L.%22%29&pagesize-30">Contreras-Vidal, Jose L. (committee member), Gorniak, Stacey L. (committee member), Thrasher, Timothy Adam (committee member), O'Connor, Daniel P. (committee member).

Subjects/Keywords: Stochastic resonance; Aging; Kinesiology

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APA (6^th Edition):

Dettmer, M. (2014). VIBRATION OF THE FOOT SOLE AS AN INTERVENTION TO IMPROVE OLDER ADULTS’ POSTURAL STABILITY. (Doctoral Dissertation). University of Houston. Retrieved from http://hdl.handle.net/10657/724

Chicago Manual of Style (16^th Edition):

Dettmer, Marius. “VIBRATION OF THE FOOT SOLE AS AN INTERVENTION TO IMPROVE OLDER ADULTS’ POSTURAL STABILITY.” 2014. Doctoral Dissertation, University of Houston. Accessed January 20, 2021. http://hdl.handle.net/10657/724.

MLA Handbook (7^th Edition):

Dettmer, Marius. “VIBRATION OF THE FOOT SOLE AS AN INTERVENTION TO IMPROVE OLDER ADULTS’ POSTURAL STABILITY.” 2014. Web. 20 Jan 2021.

Vancouver:

Dettmer M. VIBRATION OF THE FOOT SOLE AS AN INTERVENTION TO IMPROVE OLDER ADULTS’ POSTURAL STABILITY. [Internet] [Doctoral dissertation]. University of Houston; 2014. [cited 2021 Jan 20]. Available from: http://hdl.handle.net/10657/724.

Council of Science Editors:

Dettmer M. VIBRATION OF THE FOOT SOLE AS AN INTERVENTION TO IMPROVE OLDER ADULTS’ POSTURAL STABILITY. [Doctoral Dissertation]. University of Houston; 2014. Available from: http://hdl.handle.net/10657/724

University of Houston

8. -5837-9605. Real Time Classification of Emotions to Control Stage Lighting During Dance Performance.

Degree: MS, Biomedical Engineering, University of Houston

URL: http://hdl.handle.net/10657/3613

► Recently, there has been a growing research in the field of Electroencephalography (EEG) based recognition of emotions known as affective computing, where the subjects are… (more)

Subjects/Keywords: EEG; Real Time; Emotion Recognition

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APA (6^th Edition):

-5837-9605. (n.d.). Real Time Classification of Emotions to Control Stage Lighting During Dance Performance. (Masters Thesis). University of Houston. Retrieved from http://hdl.handle.net/10657/3613

Note: this citation may be lacking information needed for this citation format:
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No year of publication.

Chicago Manual of Style (16^th Edition):

-5837-9605. “Real Time Classification of Emotions to Control Stage Lighting During Dance Performance.” Masters Thesis, University of Houston. Accessed January 20, 2021. http://hdl.handle.net/10657/3613.

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
No year of publication.

MLA Handbook (7^th Edition):

-5837-9605. “Real Time Classification of Emotions to Control Stage Lighting During Dance Performance.” Web. 20 Jan 2021.

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
No year of publication.

Vancouver:

-5837-9605. Real Time Classification of Emotions to Control Stage Lighting During Dance Performance. [Internet] [Masters thesis]. University of Houston; [cited 2021 Jan 20]. Available from: http://hdl.handle.net/10657/3613.

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
No year of publication.

Council of Science Editors:

-5837-9605. Real Time Classification of Emotions to Control Stage Lighting During Dance Performance. [Masters Thesis]. University of Houston; Available from: http://hdl.handle.net/10657/3613

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
No year of publication.

University of Houston

9. Guo, Jielian. Superpixel Based Active Learning and Online Feature Importance Estimation for Hyperspectral Image Analysis.

Degree: MS, Electrical Engineering, University of Houston

URL: http://hdl.handle.net/10657/2158

► The rapid development of multi-channel optical imaging sensors has led to increased uti- lization of hyperspectral data for remote sensing. For classification of hyperspectral data,… (more)

Subjects/Keywords: Superpixel; Hyperspectral imaging; Active learning

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APA (6^th Edition):

Guo, J. (n.d.). Superpixel Based Active Learning and Online Feature Importance Estimation for Hyperspectral Image Analysis. (Masters Thesis). University of Houston. Retrieved from http://hdl.handle.net/10657/2158

Note: this citation may be lacking information needed for this citation format:
No year of publication.

Chicago Manual of Style (16^th Edition):

Guo, Jielian. “Superpixel Based Active Learning and Online Feature Importance Estimation for Hyperspectral Image Analysis.” Masters Thesis, University of Houston. Accessed January 20, 2021. http://hdl.handle.net/10657/2158.

Note: this citation may be lacking information needed for this citation format:
No year of publication.

MLA Handbook (7^th Edition):

Guo, Jielian. “Superpixel Based Active Learning and Online Feature Importance Estimation for Hyperspectral Image Analysis.” Web. 20 Jan 2021.

Note: this citation may be lacking information needed for this citation format:
No year of publication.

Vancouver:

Guo J. Superpixel Based Active Learning and Online Feature Importance Estimation for Hyperspectral Image Analysis. [Internet] [Masters thesis]. University of Houston; [cited 2021 Jan 20]. Available from: http://hdl.handle.net/10657/2158.

Note: this citation may be lacking information needed for this citation format:
No year of publication.

Council of Science Editors:

Guo J. Superpixel Based Active Learning and Online Feature Importance Estimation for Hyperspectral Image Analysis. [Masters Thesis]. University of Houston; Available from: http://hdl.handle.net/10657/2158

Note: this citation may be lacking information needed for this citation format:
No year of publication.

University of Houston

10. -7613-6444. Data-Driven, Label Consistent, Dictionary Learning Methods for Analysis of Biological Datasets.

Degree: PhD, Electrical Engineering, University of Houston

URL: http://hdl.handle.net/10657/3531

► The goal of this thesis is to develop a data-driven, label consistent, and dictionary learning based framework that can be applied on a variety of… (more)

▼ The goal of this thesis is to develop a data-driven, label consistent, and dictionary learning based framework that can be applied on a variety of signal analysis problems. Current methods based on analytical models do not adequately take the variability within and across datasets into consideration when designing signal analysis algorithms. This variability can be added as a morphological constraint to improve the signal analysis algorithms. In particular, this work focuses on three different applications: 1) we present a method for large-scale automated three-dimensional (3-D) reconstruction and profiling of microglia populations in extended regions of brain tissue for quantifying arbor morphology, sensing activation states, and analyzing the spatial distributions of cell activation patterns in tissue; this work provided an opportunity to profile the distribution of microglia in the controlled and device implanted brain. 2) we present a novel morphological constrained spectral unmixing (MCSU) algorithm that combines the spectral and morphological cues in the multispectral image data cube to improve the unmixing quality, this work provided an opportunity to identify new therapeutic opportunities for pancreatic ductal adenocarcinoma (PDAC) from the images collected from humans; and finally, 3) we developed a framework to analyze neuronal response from electroencephalography (EEG) datasets acquired from the infants ranging from 6-24 months. We demonstrated that combining different frequency bands from different spatial locations, yields better classification results, instead of the traditional approach where either one or two frequency bands are used. Using an adaptation of Tibshirani’s Sparse Group LASSO algorithm, we uncovered different spatial and bio markers for understanding a human infant’s brain. These bio-markers can be used for developmental stages of infants and further analysis is required to study the clinical aspects of infant’s social and cognitive development. This work establishes the fundamental mathematical basis for the next generation of algorithms that can leverage the morphological cues from the biological datasets. The algorithm has been embedded into the open source FARSIGHT toolkit with an intuitive graphical user interface. Advisors/Committee Members: Roysam, Badrinath (advisor), Vidal%2C%20Jose%20L.%22%29&pagesize-30">Contreras-Vidal, Jose L. (advisor), Shih, Wei-Chuan (committee member), Mayerich, David (committee member), Leasure, J. Leigh (committee member), Burks, Jared (committee member).

Subjects/Keywords: Machine learning; Image analysis; EEG analysis; Image processing

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APA (6^th Edition):

-7613-6444. (n.d.). Data-Driven, Label Consistent, Dictionary Learning Methods for Analysis of Biological Datasets. (Doctoral Dissertation). University of Houston. Retrieved from http://hdl.handle.net/10657/3531

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Chicago Manual of Style (16^th Edition):

-7613-6444. “Data-Driven, Label Consistent, Dictionary Learning Methods for Analysis of Biological Datasets.” Doctoral Dissertation, University of Houston. Accessed January 20, 2021. http://hdl.handle.net/10657/3531.

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Author name may be incomplete
No year of publication.

MLA Handbook (7^th Edition):

-7613-6444. “Data-Driven, Label Consistent, Dictionary Learning Methods for Analysis of Biological Datasets.” Web. 20 Jan 2021.

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Author name may be incomplete
No year of publication.

Vancouver:

-7613-6444. Data-Driven, Label Consistent, Dictionary Learning Methods for Analysis of Biological Datasets. [Internet] [Doctoral dissertation]. University of Houston; [cited 2021 Jan 20]. Available from: http://hdl.handle.net/10657/3531.

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Author name may be incomplete
No year of publication.

Council of Science Editors:

-7613-6444. Data-Driven, Label Consistent, Dictionary Learning Methods for Analysis of Biological Datasets. [Doctoral Dissertation]. University of Houston; Available from: http://hdl.handle.net/10657/3531

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
No year of publication.

University of Houston

11. Cui, Minshan. Spectral Angle-Based Feature Extraction and Sparse Representation-Based Classification of Hyperspectral Imagery.

Degree: PhD, Electrical Engineering, University of Houston

URL: http://hdl.handle.net/10657/3674

► Remote sensing involves measuring and analyzing objects of interests through data collected by a remote imaging modality without physical contact with the objects. Hyperspectral sensors… (more)

▼ Remote sensing involves measuring and analyzing objects of interests through data collected by a remote imaging modality without physical contact with the objects. Hyperspectral sensors have become increasingly popular for a variety of remote sensing applications. Hyperspectral data are composed of densely sampled reflectance values over a wide range of the electromagnetic spectrum. Such a wealth of spectral information can provide unique spectral signatures of different materials present in a scene, which makes it especially suitable for classification tasks. In this dissertation, we present new dimensionality reduction (feature extraction) and classification algorithms for high-dimensional hyperspectral data. Specifically, we develop the theory and validate a new dimensionality reduction approach that maximizes angular separation in the lower dimensional subspace. We also propose and develop its ``local'' and ``nonlinear kernel'' variants for robust feature extraction of hyperspectral data. By preserving angular properties, the resulting subspaces demonstrate robustness to a variety of sources of variability that are commonly encountered in remote sensing applications. We also extend this approach to its ``spatial variant'' by incorporating spatial-contextual information along with spectral information from the hyperspectral images. We also optimize and develop a suitable sparse representation based classification framework for hyperspectral images. By extensive experiments on several real-world hyperspectral datasets, we demonstrate that the proposed algorithms significantly outperform the state-of-the-art methods. Further, we also demonstrate the applicability of the proposed methods for a practical environmental remote sensing task. Advisors/Committee Members: Prasad, Saurabh (advisor), Roysam, Badrinath (committee member), Vidal%2C%20Jose%20L.%22%29&pagesize-30">Contreras-Vidal, Jose L. (committee member), Labate, Demetrio (committee member), Papadakis, Emanuel I. (committee member).

Subjects/Keywords: Remote sensing; Machine learning

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APA (6^th Edition):

Cui, M. (n.d.). Spectral Angle-Based Feature Extraction and Sparse Representation-Based Classification of Hyperspectral Imagery. (Doctoral Dissertation). University of Houston. Retrieved from http://hdl.handle.net/10657/3674

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Chicago Manual of Style (16^th Edition):

Cui, Minshan. “Spectral Angle-Based Feature Extraction and Sparse Representation-Based Classification of Hyperspectral Imagery.” Doctoral Dissertation, University of Houston. Accessed January 20, 2021. http://hdl.handle.net/10657/3674.

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MLA Handbook (7^th Edition):

Cui, Minshan. “Spectral Angle-Based Feature Extraction and Sparse Representation-Based Classification of Hyperspectral Imagery.” Web. 20 Jan 2021.

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Vancouver:

Cui M. Spectral Angle-Based Feature Extraction and Sparse Representation-Based Classification of Hyperspectral Imagery. [Internet] [Doctoral dissertation]. University of Houston; [cited 2021 Jan 20]. Available from: http://hdl.handle.net/10657/3674.

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Council of Science Editors:

Cui M. Spectral Angle-Based Feature Extraction and Sparse Representation-Based Classification of Hyperspectral Imagery. [Doctoral Dissertation]. University of Houston; Available from: http://hdl.handle.net/10657/3674

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University of Houston

12. Von Sternberg, Nicholas Craig 1986-. Novel Core Technologies and Systems for Magnetic Resonance Compatible Robotics.

Degree: PhD, Robotics, University of Houston

URL: http://hdl.handle.net/10657/4097

► This dissertation presents design and validation of several systems and technologies for magnetic resonance imaging (MRI) compatible positioning. The research began as the development of… (more)

Subjects/Keywords: MRI-compatible robotics; MR Compatible Actuation; Solid Media Flexible Transmission; Robotic Surgery; Magnetic resonance imaging

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APA (6^th Edition):

Von Sternberg, N. C. 1. (n.d.). Novel Core Technologies and Systems for Magnetic Resonance Compatible Robotics. (Doctoral Dissertation). University of Houston. Retrieved from http://hdl.handle.net/10657/4097

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Chicago Manual of Style (16^th Edition):

Von Sternberg, Nicholas Craig 1986-. “Novel Core Technologies and Systems for Magnetic Resonance Compatible Robotics.” Doctoral Dissertation, University of Houston. Accessed January 20, 2021. http://hdl.handle.net/10657/4097.

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MLA Handbook (7^th Edition):

Von Sternberg, Nicholas Craig 1986-. “Novel Core Technologies and Systems for Magnetic Resonance Compatible Robotics.” Web. 20 Jan 2021.

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Vancouver:

Von Sternberg NC1. Novel Core Technologies and Systems for Magnetic Resonance Compatible Robotics. [Internet] [Doctoral dissertation]. University of Houston; [cited 2021 Jan 20]. Available from: http://hdl.handle.net/10657/4097.

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Council of Science Editors:

Von Sternberg NC1. Novel Core Technologies and Systems for Magnetic Resonance Compatible Robotics. [Doctoral Dissertation]. University of Houston; Available from: http://hdl.handle.net/10657/4097

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University of Houston

13. Zhang, Yuhang. Information Fusion for Multi-Source Data Classification.

Degree: PhD, Electrical Engineering, University of Houston

URL: http://hdl.handle.net/10657/3675

► Multi-source data, either from different sensors or disparate features extracted from the same sensor, are often valuable for data analysis due to their potential for… (more)

▼ Multi-source data, either from different sensors or disparate features extracted from the same sensor, are often valuable for data analysis due to their potential for providing complementary information. Effective fusion of information from such multi-source data is critical to enhanced and robust interpretation about the underlying classification problem. Nevertheless, multi-source data also bring unique challenges for data processing, e.g., high-dimensional features, lack of compact representation, and insufficient quantity of labeled data. To make the most use of multi-source data and to address the above challenges, in this research, we develop and validate data fusion algorithms on multiple datasets in two active research areas: remote sensing and brain machine interface (BMI). We develop a mixture-of-kernels approach for data fusion, and demonstrate its efficacy at fusion of multi-source data in the kernel space. In the proposed approach, each source of data is represented by a dedicated kernel – one can then learn a classifier (or an ``optimal'' feature subspace) by optimizing the kernel parameters for maximum discriminative potential. A direct related benefit is that this learning framework provides a natural and automated mechanism to learn weight distributions in the weighted mixture of kernels, that are strongly indicative of strengths and weaknesses of various sources in the underlying multi-source data analysis problem. We illustrate the benefit of this property and apply it to infer the relative importance of different sources of information in a BMI application. Additionally, to save the labor of labeling a large quantity of samples in real world remote sensing applications, an ensemble based multiple kernel active learning framework is proposed to effectively select important unlabeled samples from multi-source data for classification. We also propose a multi-source feature extraction method based on a composite kernel mapping, to project the multi-source data to a lower dimensional subspace for effective feature fusion. Finally, to effectively represent multi-source data in a compact and robust manner, we propose a joint sparse representation model with adaptive locality weights for classification. By adapting the penalty on individual atoms in the dictionary, we show that one can achieve better signal representation and reduce estimation errors. Further, we also develop a kernel variant of the proposed fusion framework, which is conceptually consistent and aligned with the mixture-of-kernels approach developed previously. Advisors/Committee Members: Prasad, Saurabh (advisor), Vidal%2C%20Jose%20L.%22%29&pagesize-30">Contreras-Vidal, Jose L. (advisor), Roysam, Badrinath (committee member), Labate, Demetrio (committee member), Crawford, Melba M. (committee member).

Subjects/Keywords: Data fusion; Hyperspectral imaging; Classification; Brain computer interface (BCI); Electroencephalography (EEG)

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Zhang, Y. (n.d.). Information Fusion for Multi-Source Data Classification. (Doctoral Dissertation). University of Houston. Retrieved from http://hdl.handle.net/10657/3675

Note: this citation may be lacking information needed for this citation format:
No year of publication.

Chicago Manual of Style (16^th Edition):

Zhang, Yuhang. “Information Fusion for Multi-Source Data Classification.” Doctoral Dissertation, University of Houston. Accessed January 20, 2021. http://hdl.handle.net/10657/3675.

Note: this citation may be lacking information needed for this citation format:
No year of publication.

MLA Handbook (7^th Edition):

Zhang, Yuhang. “Information Fusion for Multi-Source Data Classification.” Web. 20 Jan 2021.

Note: this citation may be lacking information needed for this citation format:
No year of publication.

Vancouver:

Zhang Y. Information Fusion for Multi-Source Data Classification. [Internet] [Doctoral dissertation]. University of Houston; [cited 2021 Jan 20]. Available from: http://hdl.handle.net/10657/3675.

Note: this citation may be lacking information needed for this citation format:
No year of publication.

Council of Science Editors:

Zhang Y. Information Fusion for Multi-Source Data Classification. [Doctoral Dissertation]. University of Houston; Available from: http://hdl.handle.net/10657/3675

Note: this citation may be lacking information needed for this citation format:
No year of publication.

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