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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.
291

Testing and Evaluation of a Novel Virtual Reality Integrated Adaptive Driving System

Fowler, Matthew R 07 April 2010 (has links)
Virtual simulators have proven to be extremely effective tools for training individuals for tasks that might otherwise be cost-prohibitive, dangerous, or impractical. One advantage of using a virtual simulator is that it provides a safe environment for emergency scenarios. For many years the United States military and NASA have used simulators, including those affixed with drive-by-wire (DBW) controls, effectively and efficiently to train subjects in a variety of ways. A DBW system utilizes electrical circuits to actuate servo motors from a given input signal to achieve a desired output. In DBW systems the output is not directly mechanically connected to a control surface (steering, acceleration, deceleration, etc.); usually, the input controller is linked by electrical wires to a localized servo motor where direct control can be given. This project is aimed at developing a novel simulator for a future training program using DBW systems that caters specifically to individuals who currently use or will be using for the first time vehicle modifications in order to drive and maintain their independence. Many of these individuals use one or a combination of powered steering, acceleration, braking, or secondary DBW controls to drive. The simulator integrates a virtual training environment and advanced electronic vehicle interface technology (AEVIT) DBW controls (4-way joystick, gas-brake lever/small zero-effort steering wheel). In a 30 participant study of three groups (able-bodied individuals, elderly individuals, and individuals with disability), it was found that training with a DBW joystick steering system will require more instruction and simulator practice time than a gas-brake lever/small steering wheel combination (GB/S) to obtain a similar level of competency. Drivers using the joystick completed predetermined driving courses in longer times, at slower speeds, with more errors than the other DBW system. On average, the reaction time to a stopping signal was fastest with the gas-brake lever at 0.54 seconds. Reaction times for the standard vehicle controls and the joystick were 0.741 and 0.677 seconds respectively. It was noted that reaction times using DBW controls were shorter overall. When driving in traffic, drivers committed 4.9, 5.1, and 8.3 driving infractions per minute using standard vehicle controls (No Drive by Wire, (NDBW)), the gas/brake and steering system, and joystick system respectively. Most drivers felt that the GB/S system was easier to learn, easier to operate, safer, and more reliable than the joystick system.
292

An Investigation of Simple Reaction Time and Movement Time of the Dominant and Non-dominant Hand of Elementary School Children

Bartee, Horace Hayne 08 1900 (has links)
The purpose of this study was to investigate the reaction time and speed of movement of the dominant and non-dominant arms of elementary-school boys and girls.
293

Investigating the Cortical and Subcortical Contributions to Unimanual and Bimanual Wrist Extension

Teku, Faven 19 April 2021 (has links)
When exploring movement production, motor control researchers have been interested in investigating the relative contributions to different types of movement. In a research setting, a startling acoustic stimulus (SAS) can be used as a tool to explore the neural processes that are occurring when preparing and initiating a movement. Additionally, suprathreshold TMS is another tool which can induce a suppression of the cortical region of the brain, resulting in RT delays which provides us with the ability to assess the corticospinal contributions to a particular movement. The aim of the current study was to investigate potential differences in the planning and execution of bimanual versus unimanual wrist extension movements. It was of particular interest as to whether bimanual coupling occurs at the cortical level or in lower parts of the output pathway (reticulospinal). Participants (N=6) were instructed to complete a unimanual or bimanual wrist extension following a control go-signal or a SAS. For subset of trials, in order to explore the level of corticospinal excitability of the movement, suprathreshold TMS was applied over the left M1 during the task to induce a cortical silent period (CSP). Results revealed that theimpact of TMS on response initiation was not significantly different for unimanual task versus a bimanual task. Furthermore, the SP (silent period) only had an impact on the right limb and not the left during the bilateral task. Lastly, SAS did lead to shorter RTs for both the unimanual and bimanual wrist extension task, but the RT delay induced by TMS in the right limb was not shorter in SAS trials compared to control. The findings of the present study suggest that bimanual coupling may be occurring at the cortical level and in lower parts of the output pathway as there may be correlated neural activity in the two hemispheres occurring during bimanual wrist extension movements.
294

Range Modulation Strategy for Minimizing Interference in Vehicle-to-Vehicle Safety Communication

Parrish, Mason D. 22 April 2022 (has links)
No description available.
295

Effects of a Custom Bite-Aligning Mouthguard on Performance in College Football Players

Drum, Scott N., Swisher, Anna M., Buchanan, Christina A., Donath, Lars 01 May 2016 (has links)
Effects of a custom bite-aligning mouthguard on performance in college football players. J Strength Cond Res 30(5): 1409-1415, 2016 - Besides injury prevention, mouthguards can also be employed to improve physical performance. The effects of personalization of mouthguards have rarely been investigated. This 3-armed, randomized, controlled crossover trial investigated the difference of wearing (a) personalized or custom-made (CM, e.g., bite-aligned), (b) standard (BB, boil and bite), and (c) no (CON) mouthguards on general fitness parameters in experienced collegiate football players. A group of 10 upperclassmen (age, 19-22 years; mean ± SD: age 20.7 ± 0.8 years; body mass 83 ± 7.4 kg; height 179.1 ± 5.2 cm; body mass index 25.9 ± 2.2 kg·cm -2), National Collegiate Athletic Association Division II football players with at least 2 years of playing experience, were randomly assigned to the 3 mouthguard conditions: a randomized, within-subjects repeated-measures design was applied. All participants were randomly tested on strength and endurance performance Vo 2 max testing, with Bruce treadmill protocol including (a) time to fatigue, (b) blood lactate concentration in millimoles per liter at stage 2 and (c) at peak fatigue, (d) flexibility, (e) reaction time, (f) squat vertical jump, (g) countermovement vertical jump, and (h) 1 repetition maximum bench press. Repeated-measures analysis of variance showed no significant differences between the 3 conditions for each outcome variable (0.23 < p < 0.94; 0.007 < < 0.15). These data indicate that CM mouthguards did not superiorly affect general fitness parameters compared with BB and CON. In turn, protective BB or CM mouthpieces did not appear to impair general fitness performance vs. CON. The recommendation of a custom bite-aligning mouthguards for performance enhancement in young Division II football players is questioned. Further studies with larger sample sizes, gender comparison, and (sport) discipline-specific performance testing are needed.
296

Visual response of neurons in the lateral intraparietal area and saccadic reaction time during a visual detection task. / 視覚検出課題における頭頂間溝外側壁ニューロンの視覚応答活動とサッカード眼球運動潜時の関係

Tanaka, Tomohiro 23 May 2013 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第17778号 / 医博第3804号 / 新制||医||999(附属図書館) / 30585 / 京都大学大学院医学研究科医学専攻 / (主査)教授 大森 治紀, 教授 髙橋 良輔, 教授 吉村 長久 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
297

Establishing the use of Pseudomonas spp. as biocontrol agents of fungal and nematode pathogens

Kimmelfield, Rebecca B. January 2020 (has links)
No description available.
298

Combined Punishment and Reward Feedback During Sequence Learning

Sidhu, Rajbir January 2021 (has links)
Punishment and reward feedback during motor learning tasks appear to have some beneficial impact on learning and retention, respectively. Therefore, it is possible that combining punishment and reward feedback would benefit both learning and retention. Within the sports coaching domain, a combination of punishment and reward feedback schedule has been suggested to improve performance. According to the coaching literature, the most effective approach is providing reward-to-punishment feedback. However, transitioning from punishment-to-reward feedback may be more effective based on the motor learning literature. The present study examined the utility of combining punishment and reward feedback through a transition schedule approach during a serial reaction time task. To test the competing predictions about feedback order, half the participants received punishment-to-reward feedback and the other half received the reverse order. Our results revealed that training response time significantly improved with no significant difference between the order of feedback. However, both types of feedback order did not improve retention during the same-day and delayed post-tests. Yet, the non-significant equivalence test indicates that these findings remain inconclusive. Finally, within-subjects analysis of the punishment and reward conditions found that training significantly improved response time with no difference between them. In this case, the equivalence test was significant, revealing that the estimated effect was surprisingly small. Overall, the current study failed to find conclusive evidence that the order of a transition feedback schedule matters for learning and retention. However, the difference between punishment and reward conditions may be smaller than previously assumed by motor learning studies. / Thesis / Master of Science (MSc) / An important part of learning any skill is receiving information that helps us recognize mistakes and improve our performance, known as feedback. In fact, feedback presented as a punishment or reward has been shown to improve an individual's ability to learn and retain skills, respectively. Therefore, can combining punishment and reward feedback benefit both learning and retention? One way to deliver both types of feedback is using a transition schedule. Some have recommended that transitioning from punishment to reward feedback would be most effective, while others have suggested the reverse order. The current study examined whether the order of receiving punishment and reward feedback affected learning and retention. To test this, subjects either received punishment-to-reward feedback or reward-to-punishment feedback during a key-pressing task. Our results did not find conclusive evidence that the order mattered for learning and retention. Furthermore, the difference between punishment and reward feedback overall was smaller than previously thought. These findings highlight that more studies may need to be conducted to get a better understanding of whether the order of punishment and reward feedback can benefit both learning and retention.
299

The effect of vitamin B-12 supplementation on visual reaction time in young adult females

Servalish, Sean M 12 May 2023 (has links) (PDF)
This study investigated the effect of vitamin B-12 supplementation on visual response time (VRT). Menstrual cycle phase (MCP) and 24-hour dietary intake of B-12 were also observed as dependent variables. This blind, placebo-controlled trial observed 14 young adult females in four treatment groups: control, 500mcg (low dose), 2000mcg (moderate dose), and 3000mcg (high dose). The study lasted 28 days, with participants treated weekly, randomly assigned to each of the treatment groups. When comparing B-12 dose treatment groups to VRT baseline, there was significant improvements in VRT. Compared to the placebo, there were no significant differences among treatment groups. Significant differences were observed among MCP in two of the four treatment groups. No significant differences were observed in 24-hour intake of B-12 prior to treatment.
300

Effects of Neuromuscular Training on the Dynamic Restraint Characteristics of the Ankle

Linford, Christena 16 March 2005 (has links) (PDF)
Objective: To examine the influence of a 6-week training program on the electromechanical delay (EMD) and reaction time of the peroneus longus muscle. Design and Setting: The study was guided by a 2 x 2 factorial design with repeated measures on the time factor. The independent variables for this study were group (training and control) and time (pre- and post-training). Dependent variables for this study were muscle reaction time and electromechanical delay of the peroneus longus muscle. Subjects: Thirty-six healthy, physically active, college-age (21.8 ± 2.3 yr) male and female (M = 14, F = 28, height = 173.7 ± 11.2 cm, weight = 69.1 ± 18.4 kg) subjects were recruited for this study. Subjects had experienced no more than one ankle sprain to either ankle in their life, and had not sprained either ankle in the last year. Subjects were not currently experiencing any lower extremity pathology and had no history of serious injury to either lower extremity. Measurements: The EMD of the peroneus longus was determined by the onset of force contribution after a percutaneous electrical stimulation was administered, as measured by EMG and force plate data. Reaction time was measured after a perturbation during walking. Data was analyzed using two 2 X 2 X 2 ANOVAs. Group (treatment and control) and gender were between treatments factors, and time was a within treatments factor. Results: Upon initial examination, there was a trend in the EMD measurements to show an increase in EMD in the treatment group. However, this lacked statistical significance (F = 2.96, p = 0.0983). Reaction time demonstrated a trend towards a decrease in reaction time in the treatment group, but again, this lacked statistical significance (F = 2.88, p = 0.1025). Effect size for this reaction time was 1.2. Conclusions: The 6-week training program used in this study did not have a significant effect on the reaction time and electromechanical delay of the peroneus longus muscle.

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