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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.
51

Gesture Based Navigation and Localization of a Smart Wheelchair using Fiducial Markers

Patel, Jayam Umesh 28 April 2016 (has links)
With the rise in aging population, about 6.8 million American residents are depen- dent on mobility devices for their day to day activity. More than 40% of these users have di?culty in moving the mobility device on their own. These numbers serve as a motivation on developing a system than can help in manipulation with simple muscle activity and localize the mobility device in the user's home in case of medical emergencies. This research is aimed at creating a user interface of Elec- tromyographic Sensor, attached to the forearm, incorporated with present smart wheelchairs and a simple localization technique using ducial markers. The main outcome of the research is a simulator of the smart wheelchair to analyze the results of my research.
52

INVESTIGATION INTO THE BARBELL BACKSQUAT COMPARING WEIGHTLIFTING SHOES TO BAREFOOT CONDITIONS

Pilkinton, Alex W 01 May 2016 (has links)
This present study was intended to investigate muscle activation patterns throughout the barbell back squat and determine if there are any differences found in EMG responses among individuals wearing weightlifting shoes and barefooted individuals. The hypothesis was that weightlifting shoes would generate significantly greater muscle activation patterns throughout the barbell back squat due to the rigid structure and raised heal in the shoe design. EMG patterns from six superficial lower extremity muscles were recorded from 12 subjects (means: 22.67 ± 2.39 age, 172,28 ± 14.04 cm height, 74.88 ± 16.11 kg mass), each meeting a specific inclusion criteria. Data collection occurred over three subject visits to determine one repetition maximum [1RM] (Day 1), conduct maximal contraction tests (Day 2), and finally to perform squat tests with the two footwear conditions (Day 3). Data was collected at 80% of the participants’ 1RM utilizing both weightlifting shoes and barefoot conditions, and EMG activity was recorded for data analysis. Paired-sample T-tests were calculated to check for any significant differences among footwear conditions, and 2X2 ANOVA testing was used to determine if any significant changes occurred among footwear conditions in the eccentric and concentric portions of the barbell back squat. The study found two main components. The first was that several muscles showed differences between eccentric and concentric phases in regards to average muscle activity. However, none of the observed muscles showed significant differences between the two footwear conditions in regard to EMG activity.
53

Utvärdering av hjälpmedel för äldre / Evaluation of assistive devices for the elderly

Erling, Fredrik, Sessman, Loisa January 2010 (has links)
<p>Äldre människor är en grupp som växer och blir allt större. På grund av åldrandetdrabbas denna grupp ofta av någon form av funktionsnedsättning. Många gångerkan den äldre populationen känna sig hotad av åldrandet, eftersom den påverkarindividens självständighet. Ett sätt att bibehålla självständigheten är att användahjälpmedel. Idag finns många hjälpmedel på marknaden, vilket också ökatbehovet av att utvärdera hur väl produkterna uppfyller sin funktion. Ett företagsom tillverkar hjälpmedel för äldre är ComfortSystem AB (CS). Syftet med dettaprojekt har varit att utvärdera två hjälpmedel för att ta sig ur säng och detta meden lämplig metod för produktutvärdering. Målet med projektet har varit attanvända den utvalda metoden för att redovisa siffror som ett resultat av produktutvärderingen.Med Puhgs utvärderingsmatris valdes elektromyografi (EMG) somen lämplig utvärderingsmetod. Vid tillämpning av EMG visade detta att vidanvändning av produkterna sker en förändring av muskelaktiviteten för m. rectusabdominis och m. obliquus externus abdominis när hjälpmedlen används jämförtmed att ta sig ur säng och att inte använda dem. En intervju genomfördes medföretaget för att undersöka resultatets betydelse för CSs produktutvecklingsprocess.För ett statistiskt säkert resultat krävs vidare studier med fler testpersoner.</p> / <p>The elderly are a constantly growing part of the population. Due to aging,members of this group are often subjects to some kind of disability. It is quitecommon that elderly feel frightened by their aging as it may affect the individual'sindependence. One way to maintain independence is to use assistive devices.There are currently many such devices on the market, something that has calledfor better ways to determine how well these products operate. A company that ismanufacturing assistive devices for the elderly is ComfortSystem AB (CS). Thepurpose of this project was to evaluate two assistive devices for getting in and outof bed, using a suitable method for product evaluation. The goal of the project wasto apply the chosen method to present numbers as a result of the evaluation. UsingPugh's evaluation matrix electromyography (EMG) was chosen as a suitableevaluation method. When EMG was applied it was showed that there is a changein the muscle activity among the m. rectus abdominis and m. externus obliquusabdominis when using the assistive devices compared to getting out of bed andnot using the devices. An interview was conducted with the company to establishthe impact of the chosen method on CS's product development process. For astatistically sound result more studies using more subjects are necessary.</p>
54

Implementation and Validation of a Detailed 3D Inverse Dynamics Lower Extremity Model for Gait Analysis Applications Based on Optimization Technique

Eltoukhy, Moataz 20 April 2011 (has links)
The goal of this research work was to introduce the whole process of developing and validating a 3D lower extremity musculoskeletal model and to test the ability of the model to predict the muscles recruitment of the different muscles involved in human locomotion as well as determining the corresponding forces and moments generated around the different joints in the lower extremity. Therefore the model can be applied in one of the important fields of orthopaedics which is joint replacement; the case study used in such application is the total knee replacement. The knee reaction forces were compared to the pattern obtained by Harrington (1992), where the hip moment components (Flexion/extension, internal/external, and abduction/adduction) were all compared to the patterns obtained from the Hip98 data base. It was shown in the different graphs of joints forces and moments that the model was able to produce very close results when comparing pattern and magnitude to the literature data. Thus, this 3D biomechanical model is sophisticated enough to be used for surgery evaluation such as in total knee replacement, where the damaged cartilage and bone are removed from the surface of the knee joint and replaced with a man-made. The case study of the second part of the research work presented involved the comparison of the gait pattern between two main knee joint types, Metallic and Allograft knee joints against normal subjects (Control group). A total of fifteen subjects participated in this study, five subjects in each group. It was concluded that based on the study conducted and the statistical evidence obtained that the introduced model can be used for applications that involves joint surgeries such as knee replacement that ultimately can be utilized in surgery evaluation.
55

Automated Measurement of Neuromuscular Jitter Based on EMG Signal Decomposition

He, Kun January 2007 (has links)
The quantitative analysis of decomposed electromyographic (EMG) signals reveals information for diagnosing and characterizing neuromuscular disorders. Neuromuscular jitter is an important measure that reflects the stability of the operation of a neuromuscular junction. It is conventionally measured using single fiber electromyographic (SFEMG) techniques. SFEMG techniques require substantial physician dexterity and subject cooperation. Furthermore, SFEMG needles are expensive, and their re-use increases the risk of possible transmission of infectious agents. Using disposable concentric needle (CN) electrodes and automating the measurment of neuromuscular jitter would greatly facilitate the study of neuromuscular disorders. An improved automated jitter measurment system based on the decomposition of CN detected EMG signals is developed and evaluated in this thesis. Neuromuscular jitter is defined as the variability of time intervals between two muscle fiber potentials (MFPs). Given the candidate motor unit potentials (MUPs) of a decomposed EMG signal, which is represented by a motor unit potential train (MUPT), the automated jitter measurement system designed in this thesis can be summarized as a three-step procedure: 1) identify isolated motor unit potentials in a MUPT, 2) detect the significant MFPs of each isolated MUP, 3) track significant MFPs generated by the same muscle fiber across all isolated MUPs, select typical MFP pairs, and calculate jitter. In Step one, a minimal spanning tree-based 2-phase clustering algorithm was developed for identifying isolated MUPs in a train. For the second step, a pattern recognition system was designed to classify detected MFP peaks. At last, the neuromuscular jitter is calculated based on the tracked and selected MFP pairs in the third step. These three steps were simulated and evaluated using synthetic EMG signals independently, and the whole system is preliminary implemented and evaluated using a small simulated data base. Compared to previous work in this area, the algorithms in this thesis showed better performance and great robustness across a variety of EMG signals, so that they can be applied widely to similar scenarios. The whole system developed in this thesis can be implemented in a large EMG signal decomposition system and validated using real data.
56

The Influence of Q-Angle and Gender on the Stair-Climbing Kinetics and Kinematics of the Knee

Cartwright, Alexis Marion 21 September 2007 (has links)
Background: Knee joint motion and quadriceps activity play a crucial role in all lower limb tasks, especially those which are highly dynamic and weight-bearing. Due to anatomical differences between men and women such as height, leg length, and hip width, alignment and mechanics of the lower limb are different between males and females. An anatomical variable which is associated with alignment in the lower limb is the quadriceps muscle angle (q-angle). The purpose of this study is to determine if there is a relationship between q-angle, activity of the quadriceps and hamstring muscles and the kinetics and kinematics of the knee during stairclimbing. An investigation on the reliability of q-angle measurements was also made prior to the primary study. Methods: To test the interclass reliability of q-angle measurements, three individuals measured the q-angle on 20 subjects. The primary researcher measured the same twenty individuals on three separate days to determine intra-rater reliability. The primary study involved 10 male and 10 female subjects completing 20 stair-climbing trials (10 ascent, 10 descent). Kinematic and kinetic data were collected on the lower limbs as well as electromyography (EMG) on two quadriceps muscles and one hamstring muscle. Knee joint peak and occurrence of peak moments, average EMG amplitude and peak and occurrence of peak EMG were analyzed by gender and high and low q-angle. A two way analysis of variance (ANOVA) was used to test the statistical significance of each measured variable (alpha = 0.05). Results & Discussion: The inter-rater reliability for q-angle was low (0.27-0.78) but the intrarater reliability showed q-angle measurements to be very reliable (0.80-0.95). For study 2, it was found that females had increased vastus lateralis and vastus medialis peak EMG and average EMG amplitudes for stair ascent and descent compared to males. Furthermore, for descent only, females demonstrated having delayed occurrence of peak EMG for vastus lateralis and biceps femoris, and exhibited an increased peak knee extension moment and a decreased peak knee adduction moment compared to males. For q-angle, there was a significant difference found for biceps femoris occurrence of peak EMG during descent, with the high q-angle group having delayed occurrence of peak. For ascent, the high q-angle group had significantly increased average vastus lateralis EMG and an earlier occurrence of knee abduction moment. Q-angles were found to be higher for women compared to men. Conclusion: This study confirms that gender differences do exist in knee moment and thigh EMG parameters with stair ascent and stair descent. With the high incidence of significant findings for the quadriceps muscle, further investigation is warranted to determine if a relationship does exist between q-angle and knee joint function. It would also be recommended that hip mechanics be included in future studies due to the difference seen in adduction moments at the knee.
57

The Effect of Situational Attribution Training on Majority Group Members’ Psychophysiological Responses to Out-group Members

Myers, Ashley 11 May 2012 (has links)
The present research explored the effects of Situational Attribution Training (Stewart, Latu, Kawakami, & Myers, 2010) on affective bias utilizing facial electromyography (EMG). Participants viewed a slideshow of randomly presented photographs of both and White and Black American men while rating how “friendly” each individual appeared. Simultaneously, corrugator and zygomaticus region activity, linked with positive and negative affect, respectively, was measured. Of these participants, half were randomly assigned to complete Situational Attribution Training beforehand. Results for EMG activity suggested no significant differences in EMG activity for White compared to Black photographs for either the training or control participants; thus, this study did not find evidence of affective bias by way of corrugator or zygomaticus activity. However, errors in slideshow presentation prevent clear interpretation of these results. Suggestions for future research and ways in which bias errors can be avoided are discussed.
58

Automated Measurement of Neuromuscular Jitter Based on EMG Signal Decomposition

He, Kun January 2007 (has links)
The quantitative analysis of decomposed electromyographic (EMG) signals reveals information for diagnosing and characterizing neuromuscular disorders. Neuromuscular jitter is an important measure that reflects the stability of the operation of a neuromuscular junction. It is conventionally measured using single fiber electromyographic (SFEMG) techniques. SFEMG techniques require substantial physician dexterity and subject cooperation. Furthermore, SFEMG needles are expensive, and their re-use increases the risk of possible transmission of infectious agents. Using disposable concentric needle (CN) electrodes and automating the measurment of neuromuscular jitter would greatly facilitate the study of neuromuscular disorders. An improved automated jitter measurment system based on the decomposition of CN detected EMG signals is developed and evaluated in this thesis. Neuromuscular jitter is defined as the variability of time intervals between two muscle fiber potentials (MFPs). Given the candidate motor unit potentials (MUPs) of a decomposed EMG signal, which is represented by a motor unit potential train (MUPT), the automated jitter measurement system designed in this thesis can be summarized as a three-step procedure: 1) identify isolated motor unit potentials in a MUPT, 2) detect the significant MFPs of each isolated MUP, 3) track significant MFPs generated by the same muscle fiber across all isolated MUPs, select typical MFP pairs, and calculate jitter. In Step one, a minimal spanning tree-based 2-phase clustering algorithm was developed for identifying isolated MUPs in a train. For the second step, a pattern recognition system was designed to classify detected MFP peaks. At last, the neuromuscular jitter is calculated based on the tracked and selected MFP pairs in the third step. These three steps were simulated and evaluated using synthetic EMG signals independently, and the whole system is preliminary implemented and evaluated using a small simulated data base. Compared to previous work in this area, the algorithms in this thesis showed better performance and great robustness across a variety of EMG signals, so that they can be applied widely to similar scenarios. The whole system developed in this thesis can be implemented in a large EMG signal decomposition system and validated using real data.
59

The Influence of Q-Angle and Gender on the Stair-Climbing Kinetics and Kinematics of the Knee

Cartwright, Alexis Marion 21 September 2007 (has links)
Background: Knee joint motion and quadriceps activity play a crucial role in all lower limb tasks, especially those which are highly dynamic and weight-bearing. Due to anatomical differences between men and women such as height, leg length, and hip width, alignment and mechanics of the lower limb are different between males and females. An anatomical variable which is associated with alignment in the lower limb is the quadriceps muscle angle (q-angle). The purpose of this study is to determine if there is a relationship between q-angle, activity of the quadriceps and hamstring muscles and the kinetics and kinematics of the knee during stairclimbing. An investigation on the reliability of q-angle measurements was also made prior to the primary study. Methods: To test the interclass reliability of q-angle measurements, three individuals measured the q-angle on 20 subjects. The primary researcher measured the same twenty individuals on three separate days to determine intra-rater reliability. The primary study involved 10 male and 10 female subjects completing 20 stair-climbing trials (10 ascent, 10 descent). Kinematic and kinetic data were collected on the lower limbs as well as electromyography (EMG) on two quadriceps muscles and one hamstring muscle. Knee joint peak and occurrence of peak moments, average EMG amplitude and peak and occurrence of peak EMG were analyzed by gender and high and low q-angle. A two way analysis of variance (ANOVA) was used to test the statistical significance of each measured variable (alpha = 0.05). Results & Discussion: The inter-rater reliability for q-angle was low (0.27-0.78) but the intrarater reliability showed q-angle measurements to be very reliable (0.80-0.95). For study 2, it was found that females had increased vastus lateralis and vastus medialis peak EMG and average EMG amplitudes for stair ascent and descent compared to males. Furthermore, for descent only, females demonstrated having delayed occurrence of peak EMG for vastus lateralis and biceps femoris, and exhibited an increased peak knee extension moment and a decreased peak knee adduction moment compared to males. For q-angle, there was a significant difference found for biceps femoris occurrence of peak EMG during descent, with the high q-angle group having delayed occurrence of peak. For ascent, the high q-angle group had significantly increased average vastus lateralis EMG and an earlier occurrence of knee abduction moment. Q-angles were found to be higher for women compared to men. Conclusion: This study confirms that gender differences do exist in knee moment and thigh EMG parameters with stair ascent and stair descent. With the high incidence of significant findings for the quadriceps muscle, further investigation is warranted to determine if a relationship does exist between q-angle and knee joint function. It would also be recommended that hip mechanics be included in future studies due to the difference seen in adduction moments at the knee.
60

Motoriska läpp-asymmetrier hos personer som stammar : En elektromyografisk studie

Lundbäck, Emma, Svahn, Rut January 2012 (has links)
Studien syftade till att undersöka skillnader i mun-asymmetrier mellan personer som stammar och normaltalande med hjälp av elektromyografi (EMG). Eventuella avvikande asymmetrier i muskelaktivitet antogs återspegla avvikande cerebral kontroll av talmotoriken. Studien ämnade även jämföra mun-asymmetrier under stammat och stamningsfritt tal, samt studera eventuella samband mellan asymmetrier och stamningens svårighetsgrad. Tolv personer med stamning jämfördes med en kontrollgrupp bestående av nio personer under verbala och ickeverbala uppgifter. Ingen signifikant skillnad kunde påvisas mellan grupperna. Resultatet strider mot tidigare studier där skillnader i mun-asymmetrier hos personer med stamning har observerats. Gruppen med stamning uppvisade dock en tendens till starkare högersidig muskelaktivitet, alternativt svagare vänstersidig muskelaktivitet, under stammat tal. Motsatta mönster noterades vid flytande tal. Ett svagt samband uppvisades mellan asymmetrier i muskelaktivitet och stamningens svårighetsgrad. Tillämpad elektrodplacering visade sig ha brister i registreringen av muskelaktivitet varför författarna reserverar sig från att dra slutgiltiga slutsatser.

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