Thesis (Ph. D.)--School of Education. University of Missouri--Kansas City, 2006. / "A dissertation in counseling psychology." Advisor: Chris Brown. Typescript. Vita. Title from "catalog record" of the print edition Description based on contents viewed Nov. 9, 2007. Includes bibliographical references (leaves 98-105). Online version of the print edition.

During heel-toe running, the vertical ground reaction force (VGRF) profile has both impact and active peaks. Although the mass-spring model (a single mass and a linear spring) is simple and useful to predict running characteristics, its simulation of VGRF profiles produces only a single peak rather than the double peak typically observed in running. In contrast, the mass-spring-damper model (two masses, two springs and a damper) produces a simulated force profile with two separate peak values. Running barefoot versus with shoes of varying stiffness produces VGRF profiles with quite different characteristics. The purpose of this study was to use the mass-spring and mass-spring-damper models to investigate the stiffness characteristics of human running in barefoot, hard-shoe and soft-shoe conditions. Ten recreational runners ran overground at 3.83 m/s and completed five trials of each footwear condition. Force data and two-dimensional kinematic data were recorded simultaneously at 1000 and 250 Hz respectively. Using the mass-spring model, vertical stiffnesses with the barefoot, hard-shoe and soft-shoe conditions were 27.6, 25.3 and 24.6 kN/m, respectively. Hard-shoe and soft-shoe material stiffnesses were about 150 and 100 kNm�����. Considering the leg and shoe as two springs in series, the leg's actual vertical stiffness could be estimated as 30 and 33 kNm����� for hard and soft-shoe conditions. The result suggested that runners increased their actual vertical stiffness with the sequence of barefoot, hard-shoe, and soft-shoe conditions. Using the mass-spring-damper model, the upper spring stiffness was relatively constant while the lower spring stiffness changed with footwear condition: 274, 136 and 126 kN/m, respectively. While it is mathematically convenient to model the leg and body with constant spring characteristics over time, physiologically it is likely that muscle-tendon stiffness does change during stance as muscle activity changes. This suggests that mass-spring models of running would be improved by time varying spring characteristics. Variable stiffness of the simple mass-spring model was tested using a smoothly varying stiffness function. This provided a significantly better force profile simulation for each of the footwear conditions than did the constant stiffness model. Further mass-spring-damper modeling may also be improved through incorporation of such time varying characteristics. / Graduation date: 2002

Fast medio-lateral movements, frequent in a number of sports activities, are associated with lower extremity injuries. These injuries may occur as a result of excessive musculoskeletal stresses on the joints and their associate structures. The purpose of this study was to investigate the effect of running speed and turning movement on the three-dimensional moments at the ankle, knee, and hip joints. Data were collected using video cameras and force plate. Eight male recreational basketball players were tested during slow (1.5 m/s), moderate (3.0 m/s), and fast running (4.5 m/s) and when cutting to the right or left (+60, +30, 0, -30, and -60��). The inverse dynamics approach was used to integrate the body segment parameter, kinematic and force plate data, and to solve the resultant joint moments. At the ankle joint, inversion/eversion, dorsi/plantar flexion, and internal/external rotation moments of the ankle joint increased with running speed (p<.05). At the knee joint, flexion/extension and abduction/adduction moments increased with running speed except flexion moment that decreased with running speed (p<.05). At the hip joint, internal/external rotation, flexion/extension, and abduction/adduction moments increased with running speed (p<.05). In medial cutting movements, greater abduction moments of the ankle, adduction moments of the knee and external rotation and adduction of the hip were found (p<.05). In lateral cutting movements, greater inversion and adduction moments of the ankle, abduction moments of the knee and hip were found (p<.05). These findings reinforce the intuitive notion that fast medio-lateral turning movements produce substantially greater musculoskeletal loading on the joint structures than does straight running and consequently have greater potential for inducing lower extremity injuries such as ankle sprain or anterior cruciate ligament injury. / Graduation date: 1999

No description available.

The widespread use of low friction PVD coatings on machine elements is limited by the high costs associated with fulfilling the demands on the surface quality of both the supporting substrate and the counter surface. In this work, an attempt is made at lowering these demands, by adding a sacrificial carbon overcoat to a TaC/aC low friction coating. Both coatings were deposited by planar magnetron DC sputtering, as separate steps in a single PVD-process. Coatings were deposited on substrates of two different surface roughnesses, in order to test the ability of this coating system to function on rougher substrates. Reciprocating ball on disc tests was performed, using balls with two different surface roughnesses. The worn surfaces were investigated using 3-D profilometry and SEM. The ability of the different overcoats to initially reduce the roughness of both the coated surface and the counter surface and to produce stable, low-friction conditions was examined for the different initial roughnesses. The implications for design of efficient run-in coatings for various systems are discussed.

The problem of dilemma zone protection and red-light-running is especially important in certain rural intersections due to the higher speeds at these intersections and their isolated nature. In addition, the presence of a larger percentage of trucks mean that adequate warning and help need to be given to these truck drivers in order to enable them to stop safely, or proceed through the intersection before the onset of red. To curb any potential danger at such intersections, a Texas Department of Transportation (TxDOT) research project on Advanced Warning for End of Green Phase (AWEGS) at high speed intersections deployed AWEGS at two rural intersection sites ?? Tx 6 @ FM 185 near Waco and US 290 @ FM 577 in Brenham. The deployment of AWEGS involved a Level 1 and a later upgrade to a more efficient Level 2 in Waco. Initial results on red-light-running, even though promising, were expressed as observed red-light-running events per day. These resulting rates did not reflect exposure, and the results also raised some concerns with regards to some increase in red-light-running from Level 1 to Level 2. A more detailed analysis of the red-light-running issue at these two sites is provided in this thesis. The main areas of red-light-running analyses presented here are with respect to the reductions in red-light-running rates for the exposure factors of number of cycles and vehicular volumes, the comparison of day and night RLR rates and the nature of speeds of vehicles running the red light at the intersection in Waco. AWEGS was found to reduce the total red-light-running per exposure factor after its deployment. Both Level 1 and Level 2 AWEGS operations were found to reduce red-light-running by up to 60%. Generally, total red-light-running per exposure factor between Level 1 and Level 2 was found to be about the same. Level 2 had lower daytime red-light-running rates and higher nighttime rates than Level 1. Generally, day rates were found to be higher than night rates for all levels of AWEGS deployment. It is recommended that, to better understand the operational aspects of AWEGS and to improve its operations, more implementation of AWEGS and further tests be done. An automated method to collect and analyze data needs to be developed as well as a means of automatically recording video data for calibration and verification It is also recommended that Level 1 technology be implemented in areas where the Level 2 technology may be either too complex or too expensive.

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2009. / Härtill 5 uppsatser.

Thesis (M.S.)--East Carolina University, 2009. / Presented to the faculty of the Department of Exercise and Sport Science. Advisor: Paul DeVita. Title from PDF t.p. (viewed May 4, 2010). Includes bibliographical references.

Fossil fuels and their byproducts are a vital part of our economy, and society. Until renewable energy sources and energy storage technologies advance to the point where they are reliable and inexpensive, the US Economy will continue to depend upon fossil fuels. Current resources are being consumed, and the "easy to reach" reserves are becoming depleted. This leads to the requirement for more exploratory drilling, and the potential for more disasters like the recent Deepwater Horizon spill in the Gulf of Mexico. Drilling is the first of several steps in the creation of a productive oil or natural gas well. Completing a well involves casing the walls in concrete to prevent damage to the surrounding rock formations and to ensure that all of the oil or gas is captured without escaping to the surrounding environment. Ensuring the piping, which is used to case wells, is assembled correctly and to manufacturer's specifications is the focus of this study. Individual pipe sections are screwed together with a requirement for torque and number of turns. Each joint must be verified to ensure integrity, and minimize the possibility of a spill or leak. The torque measurement can be accomplished by a "torque sub", a sensor installed in-line with the drill string. The torque sub is a wireless sensor that transmits torque data to the control system for logging and display. This thesis defines the parameters required to integrate a "number of turns" measurement into an existing torque sub so that both parameters can be captured, recorded and reported using a single device. The Yost Engineering 3-Space Sensor was evaluated for use in this application. The configuration that gave the most accurate data was selected, along with the determination of some correction factors to account for site specific variation in the signals. A calibration algorithm is discussed, along with several unique methods for ensuring that the sensor output doesn't drift over the course of the joint make-up process. / text

The study examines a particular aspect of the development of athletics in Scotland. The first organised clubs for the sole purpose of purely athletic competition in the contemporary sense, were cross country clubs known as harrier clubs. Through investigation of the origins, governance and the social structure of harriers clubs, the study connects these three fundamental themes in understanding sport within broader social historical study. In this study the origins of cross country running are set within a theoretical framework which recognises the nature of the urban and rural environments which defined the sport. The sport’s early growth and governance in Scotland is set alongside the broader ideological position of the ‘amateur’. Additionally, club organisation promoted the clubs as cultural institutions. Clubs served as a focus for male sociability and elevated the status of membership of the harriers. Membership meant more than just sporting engagement; it included social and civic standing. The purpose and function therefore of early clubs extended beyond participation. This study demonstrates how membership of cross country clubs conferred upon its members a status, establishing harriers clubs as important social institutions. This research shows how social networks within sport replicated society more broadly. The significance of the contribution of cross country clubs to the development of Scottish sporting culture is therefore implicit. Harriers clubs were the epitome of the complexity of sporting engagement representing both respectability and liminal behaviour.