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  • 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.
581

Analysis of Advanced Control Methods for Quadrotor Trajectory Tracking

Milburn, Tyler 08 October 2018 (has links)
No description available.
582

Comparison of Health-Related Quality of Life Trajectories in Older Breast Cancer Patients and Noncancerous Controls Over Ten Years

de Azevedo Daruge, Maria Eduarda 01 January 2023 (has links) (PDF)
The adverse effects of cancer treatment on health-related quality of life (HRQL) are the primary concern of elderly women diagnosed with breast cancer. The interplay of transient and progressive functional impairments caused by cancer therapies, alongside the accelerated physical declines associated with the normal aging process, are all negatively correlated to HRQL. This study compared the HRQL trajectories between cases and controls for ten years after diagnosis. The cancer group included 1467 women (age ≥ 65), diagnosed with primary breast cancer, registered in the Surveillance Epidemiology and End Results (SEER) cancer registry, and completed the Medicare Health Outcomes Survey (MHOS) before and after diagnosis. Controls were frequency-matched to cases with a 1:1 ratio on age and socio-economic variables. Participants reported their HRQL using SF-36/VR12 questionnaire, which was summarized into two summary scores (physical component summary (PCS) and mental component summary (MCS) and eight domain scores: physical functioning (PF), general health (GH), bodily pain (BP), role-limitation physical (RP), social functioning (SF), mental health (MH), role-limitation emotional (RE), and vitality (VT). Hierarchical Linear Modelling was utilized to assess the fixed effects of time, group, and the interaction between time and group (Time*Group) on HRQL trajectories. At the time of cancer diagnosis, cases fared worse than controls in all of the HRQL domains and summary scores. Group and time were majorly significant for PCS, PF, GH, BP, and RP, while only group was predominantly significant for mental domains (MCS, SF, MH, RE, VT). Time was also significant for SF and VT, while Time*Group was only significant for RE. Cases showed remarkable gains over controls across time in MCS, RE, MH, VT, SF, and PF. The need for intervention in improving physical health iii HRQL among older women is validated. On the other hand, the remarkable gains of cases over controls on mental domains of HRQL provoke future research to explore further patient perception on benefit-finding caused by the diagnosis and experience of cancer.
583

Effectiveness of Compensatory Vehicle Control Techniques Exhibited by Drivers after Arthroscopic Rotator Cuff Surgery

Metrey, Mariette Brink 10 July 2023 (has links)
Current return-to-drive recommendations for patients following rotator cuff repair (RCR) surgery are not uniform due to a lack of empirical evidence relating driving safety and time-after-surgery. To address the limitations of previous work, Badger et al. (2022) evaluated, on public roads, the driving fitness of patients prior to RCR and at multiple post-operative timepoints. The goal of the Badger, et al. study was to make evidence-based return-to-drive recommendations in an environment with higher fidelity than that of a simulator and not subject to biases inherent to surveys. Badger et al., however, do not fully investigate the driving practices exhibited by subjects, overlooking the potential presence of compensatory driver behaviors. Further investigation of these behaviors through observation of direct driving techniques and practices over time can specifically answer how drivers may modify their behaviors to address a perceived state of impairment. Additionally, the degree of success in vehicle operation by comparing an ideal turn to the path taken by the driver allows for a level of quantification of the effectiveness of the compensatory techniques. Moreover, driver trajectories inferred from the vehicle Controller Area Network (CAN) metrics and from global positioning system (GPS) coordinates are contrasted with the ideal turn to assess minimum requirements for future sensors that are used to make these trajectory comparisons. This investigation leverages pre-existing data collected by the Virginia Tech Transportation Institute (VTTI) and Carilion Clinic as used in the analysis performed by Badger et al. (2022). RCR patients (n=27) executed the same prescribed driving maneuvers and drove the same route in a preoperative state and at 2-, 4-, 6-, and 12-weeks post operation. Behavioral data were annotated to extract key characteristics of interest and related them to relevant vehicle sensor readings. To construct vehicle paths, data was obtained from the on-board data acquisition system (DAS). Behavioral metrics considered the use of ipsilateral vehicle controls, performance of non-primary vehicle tasks, and steering techniques utilized to assess the impact of mobility restrictions due to sling use. Sling use was found to be a significant factor in use of the non-ipsilateral hand associated with the operative extremity (i.e., operative hand) on vehicle functions and, in particular, difficulty with the gear shifting control. Additionally, when considering the performance of non-primary vehicle tasks as assessed through a prescribed visor manipulation, sling use was not a significant factor for the task duration or completion of the task in a fluid motion. Sling use was, however, significant with respect to operative hand position prior to the completion of the visor manipulation: the operative hand was often not on the steering wheel prior to the visor maneuver. In addition, the operative hand was never used to manipulate the visor when the sling was worn. One-handed steering was also more frequent with the presence of the sling. Further behavioral analysis assessed the presence of compensatory behavior exhibited by subjects during periods in which impairment was perceived. Perceived impairment was observed as a function of the different experimental timepoints. Findings indicated a significant decrease in the lateral vehicle jerk during post-operative weeks 6 and 12. Significant differences, however, were not observed in body position alteration to avoid contact with the interior vehicle cabin, in over-the-shoulder checks, and in forward leans during yield and merge maneuvers. Regarding trajectory analysis, sling use did not produce a significant difference in the error metrics between the actual and ideal paths. In completion of turning maneuvers, however, operative extremity was significant for left turns, with greater error against the ideal path observed from those in the left operative cohort compared to those in the right operative cohort. For the right turn, however, operative extremity was not found to be a significant factor. In addition, the GPS data accuracy proved insufficient to support comparison against the ideal path. Overall, findings from this study provide metrics beyond those used in Badger, et al. that can be used in answering when it is safe for rotator cuff repair patients to return-to-drive. With the limited differences observed as a function of study timepoint and sling use, it is recommended that patients are able to safely return-to-drive at two weeks post-operation. If anything, results suggest that overcompensation, as inferred from observation of safer driving behaviors than normal, is present during some experimental timepoints, particularly post-operative week 2. / Master of Science / Current recommendations based on when it is safe for rotator cuff repair patients to return-to-drive are not standard because of a lack of suitable evidence. Previous work and recommendations rely on surveys and simulators which do not create fully realistic conditions and are subject to biases. To address the limitations of previous work, Badger et. al (2022) studied actual rotator cuff repair patients on public roads prior and following operation at multiple timepoints. Badger et al., however, did not consider the potential adaptations in driver behavior due to mobility restrictions and the perception of inferiority due to injury. Additionally, the degree of success of the adaptive driving behaviors based on the error between the actual vehicle path taken and a defined ideal path have not been explored in conjunction with the injury. This investigation is based on the pre-existing data collected by the Virginia Tech Transportation Institute (VTTI) and Carilion Clinic as used in the analysis performed by Badger et al. (2022). RCR patients (n=27) executed identical driving maneuvers and drove the same route before operation and at 2-, 4-, 6-, and 12-weeks post operation. Behavioral observations were recorded and related to relevant vehicle sensor readings. To construct vehicle paths, data was taken from the on-board data acquisition system (DAS). Participants adopted different behaviors, such as using the right hand to use the turn signal when the left arm was in a sling and the left hand to operate the gear shifter when the right arm was on a sling, to assist in combating mobility restrictions. One-handed steering was also more prominent during periods of sling-use. Sling-use, however, did not produce a significant difference in error between the actual vehicle path taken and the ideal path available to the driver. For left-operated participants completing left turns, there was also greater error in comparison to the ideal path than for the group of right-operated patients. However, there was not a difference between left- and right-operated arm participant error in completion of a right turn. The GPS data did not provide a suitable approximation of vehicle trajectory. Overall, findings from this study help to answer when it is safe for rotator cuff repair patients to return-to-drive through evaluation of the effectiveness of compensatory behaviors adopted by participants. With no significant difference in turn execution based on sling use, results suggest that patients can safely return-to-drive at two weeks post-operation. In fact, results suggest that overcompensation towards safer behaviors is present during some experimental timepoints, particularly post-operative week 2.
584

A concept for automated pick-and-place motion planning for industrial robots

Scheer, Johannes, Bodenburg, Sven 12 February 2024 (has links)
Nowadays, more and more flexible and efficient processes are required in modern industrial applications. In this field, robots are a key technoligy. In this paper a application is considered, where a 6-axis-industrial robot has to pick-and-place objects time efficiently in a constantly changing environment. Therefore, a concept for automated motion planning is presented, which is composed of two steps which are path planning and trajectory generation. In this paper suitable and established model-based methods are analyzed and chosen. Eventually, the suitability of the presented concept for the considered task is shown by implementing the concept in Matlab and applying it to a 6-axis articulated robot arm.
585

Accuracy Study of a Free Particle Using Quantum Trajectory Method on Message Passing Architecture

Vadapalli, Ravi K 13 December 2002 (has links)
Bhom's hydrodynamic formulation (or quantum fluid dynamics) is an attractive approach since, it connects classical and quantum mechanical theories of matter through Hamilton-Jacobi (HJ) theory, and quantum potential. Lopreore and Wyatt derived and implemented one-dimensional quantum trajectory method (QTM), a new wave-packet approach, for solving hydrodynamic equations of motion on serial computing environment. Brook et al. parallelized the QTM on shared memory computing environment using a partially implicit method, and conducted accuracy study of a free particle. These studies exhibited a strange behavior of the relative error for the probability density referred to as the transient effect. In the present work, numerical experiments of Brook et al. were repeated with a view to identify the physical origin of the transient effect and its resolution. The present work used the QTM implemented on a distributed memory computing environment using MPI. The simulation is guided by an explicit scheme.
586

Migration Motif: A Spatial-Temporal Pattern Mining Approach for Financial Markets

Du, Xiaoxi 08 April 2009 (has links)
No description available.
587

An Examination of Violent Victimization from Adolescence to Early Adulthood

Ziegler, Jessica 03 August 2017 (has links)
No description available.
588

ADAPTIVE IMPROVEMENT OF CLIMB PERFORMANCE

GODBOLE, AMIT ARUN 02 September 2003 (has links)
No description available.
589

Particle Erosion of Gas Turbine Thermal Barrier Coating

Swar, Rohan January 2009 (has links)
No description available.
590

Uncovering Differential Symptom Courses with Multiple Repeated Outcome Measures: Interplay between Negative and Positive Symptom Trajectories in the Treatment of Schizophrenia

Chen, Lei 16 October 2012 (has links)
No description available.

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