A well-accepted idea in geomorphology is that landforms control the type and distribution of biological habitat. However, the linkages between geomorphology and ecology remain poorly understood. In rivers, the geomorphic template controls the hydraulic environment, partly shaping the river ecosystem. But what processes shape the geomorphic template? Here, I examine how two hillslope processes dominant in the Oregon Coast Range, debris flows and deep-seated landslides, affect valley floor width and channel slope, key components of the geomorphic template in riverine ecosystems. I then investigate how patterns in potential salmon habitat differ between streams dominated by deep-seated landslides and streams dominated by debris flows. I show that terrain influenced by deep-seated landslides exhibits (1) valley widths that are more variable throughout the network but less locally variable, (2) more variable channel slopes, and (3) more potential salmon habitat as well as significantly more connectivity between habitat types.

Background: The latest generation of rear-end whiplash protection systems, as found in the WHIPS Volvo and SAHR Saab, have reduced injury rates by almost 50% in comparison with the previous generation of seat/head restraint systems. Occupant behaviour, such as seated posture and seat adjustment settings, may affect the injury risk. Method: Five studies were conducted. Studie I was an injury outcome study based on insurance data. Studies II-IV investigated seat adjustment, occupant backset, and cervical retraction for drivers and occupants in different postures and positions in the car, during stationary and driving conditions. Study V compared the occupant data from studies II and III with a vehicle testing tool, the BioRID dummy, using the protocols of the ISO, RCAR, and the RCAR-IIWPG. Results: Female drivers and passengers had a threefold increased risk for medically-impairing neck injury in rear-end impacts, compared to males. Driver position had a double risk compared with front passenger seat position. Female drivers adjusted the driver seat differently to male drivers; they sat higher and closer to the steering wheel and with more upright back support. The volunteers also adjusted their seat differently to the ISO, RCAR, and RCAR-IIWPG protocol settings; both sexes sat further away from the steering wheel, and seat back angle was more upright then in the protocols. In stationary cars, backset was highest in the rear seat position and lowest in the front passenger seat position. Males had a larger backset than females. Cervical retraction decreased and backset increased for both sexes when posture changed from self-selected posture to a slouched posture. The BioRID II dummy was found to represent 96th percentile female in stature, and a 69th percentile female in weight in the volunteer group. Conclusions: Risks in car rear-end impacts differ by sex and seated position. This thesis indicates the need for a 50th percentile female BioRID dummy and re-evaluation of the ISO, RCAR, and RCAR-IIWPG protocols, and further development of new safety systems to protect occupants in rear-end impacts.

Virtual reality (VR) has become an important tool in the study of human balance. It has also been used as a training tool for seated balance and assistive mobility devices. The objective was to design a system that can be used to investigate the effect of VR on trunk muscles during perturbed sitting and perform a preliminary study with two subjects. A spherical system was designed that rotated 26º in the pitch and roll plane at three speeds. The corresponding muscle activity was recorded using EMG in the presence and absence of VR during perturbed sitting. The design was capable of performing the required motions. The results showed a maximum of 31.8% and a minimum of 3.66% muscle activity, relative to maximum voluntary contraction. Our findings suggested that our developed system was successfully able to detect a noticeable effect of VR under perturbed sitting on the subjects’ EMG responses.

The lack of adequate equipment and measurement tools in whole-body vibration has imposed significant constraints on what can be measured and what can be investigated in the field. Most current studies are limited to single direction measurements while focusing on simple postures. Besides the limitation in measurement, most of the current biomechanical measures, such as the seat-to-head transmissibility, have discrepancies in the way they are calculated across different labs. Additionally, this field lacks an important measure to quantify the subjective discomfort of individuals, especially when sitting with different postures or in multiple-axis vibration. This work begins by explaining discrepancies in measurement techniques and uses accelerometers and motion capture to provide the basis for more accurate measurement during single- and three-dimensional human vibration responses. Building on this concept, a new data collection method is introduced using inertial sensors to measure the human response in whole-body vibration. The results indicate that measurement errors are considerably reduced by utilizing the proposed methods and that accurate measurements can be gathered in multiple-axis vibration. Next, a biomechanically driven predictive model was developed to evaluate human discomfort during single-axis sinusoidal vibration. The results indicate that the peak discomfort can be captured with the predictive model during multiple seated postures. The predictive model was then modified to examine human discomfort to whole-body vibration on a larger scale with random vibrations, multiple postures, and multiple vibration directions. The results demonstrate that the predictive measure can capture human discomfort in random vibration and during varying seated postures. Lastly, a new concept called effective seat-to-head transmissibility is introduced, which describes how to combine the human body's biodynamic response to vibration from multiple directions. This concept is further utilized to quantify the human response using many different vibration conditions and seated postures during 6D vibration. The results from this study demonstrate how complicated vibrations from multiple-input and multiple-output motions can be resolved into a single measure. The proposed effective seat-to-head transmissibility concept presents an objective tool to gain insights into the effect of posture and surrounding equipment on the biodynamic response of the operators. This thesis is timely as advances in seat design for operators are increasingly important with evolving armrests, backrests, and seat suspension systems. The utilization of comprehensive measurement techniques, a predictive discomfort model, and the concept of effective seat-to-head transmissibility, therefore, would be beneficial to the fields of seat/equipment design as well as human biomechanics studies in whole-body vibration.

The primary objective of this study is to provide a greater understanding of the tectonic evolution of the Warburton, Cooper, Eromanga and Lake Eyre Basins in central Australia. However, this study additionally attempts to provide a greater understanding of lineaments. This study compares lineament data with a traditional tectonic analysis in order to evaluate lineaments and to best understand the tectonic evolution of the region.

This thesis provides much needed representative sample data for reuse life of fully seated and torqued locknuts. Most national requirements for prevailing torque locking fasteners only specify unseated reuse life. This could create a potentially dangerous situation if unseated is misinterpreted for seated. This thesis provides comparative data for seated verses unseated configuration. Six aerospace, 3 all-metal and 3 nylon insert, and one non-aerospace locknuts were tested at preloads levels of unseated, 66%, 75%, and 85% of yield of bolt. The locknuts tested are MS21043-4, NAS1291-4, NAS1805-4, MS17825-4, MS21044D4, NAS1021N4, and Grade 8. A fixture was created in order to allow for the simultaneous data collection of the applied preload and torque, along with the removal of preload without loosening the locknut. The results from testing indicate the number of reuse cycles is greater for nylon locknuts than the all-metal locknuts. Large losses, on the order of 20-50%, in prevailing torque occur between the first and second cycle of each locknut under all preloads. Tightening Torque required to achieve a certain preload was found to increase with reuse. Application of lubrication to nylon locknuts had a significant effect, reducing the reuse life and prevailing torque performance. The testing indicated the effect of preload reduced the number of reuse cycles to failure, failure occurs when the prevailing torque is measured outside the range of 3.5 to 30 in-lb. All locknuts survived unseated and 66% Y preload testing, except MS21043 which lasted about 14.5 reuse cycles at 66% Y and NAS1805 which survived 8 reuse cycles for unseated and 12.67 reuse cycles at 66% Y. NAS1805's loss of reuse life is due to hardness and material compatibility issues. The scatter of the torque measurements was low for the first three to five cycles, then as the coatings and lubrications are worn the scatter increases. The data collected from testing agrees with the torque friction equation.

Quantifying how hillslopes respond to river incision and climate change is fundamental to understanding the geomorphic evolution of tectonically uplifting landscapes during glacial-interglacial cycles. Hillslope adjustment in the form of deep-seated bedrock landslides can account for a large proportion of the regional sediment yield and denudation rates for rapidly uplifting landscapes. However, the timing and magnitude of the response of hillslopes to climatic and tectonic forcing in moderate uplift temperate maritime catchments characteristic of many active margins worldwide is not well quantified. This study seeks to investigate how hillslopes respond to climate-modulated river incision and to quantify the magnitude of the sediment flux from this response in a typical active margin setting. The non-glacialWaipaoa Sedimentary System (WSS) on the East Coast of the North Island of New Zealand consists of river catchments, coastal foothills to uplifting mountain ranges, and terrestrial and marine sediment depocentres collectively underlain by relatively young (Cretaceous and younger) sedimentary rocks within a tectonically active setting and temperate maritime climate. These attributes make theWSS similar to many coastal catchments on oceanic-continental convergent margins worldwide. However, because of widespread destruction of primary forests for conversion to pasture lands by the mid 20th Century, theWSS is currently a globally significant source of sediment to the world’s oceans. Because of these factors, theWSS was selected as one of two global study sites for the international, NSF supported, MARGINS Source-to-Sink initiative designed to investigate the transfer of sediment from terrestrial source to marine sink. Previous studies on theWSS have shown a strong link between climate change and geomorphic response in the system. River incision since the last glacial coldest period has generated a significant amount of topography, leaving small remnants of the ca.18,000 cal. yr BP last glacial aggradation terrace scattered up to 120 m above modern rivers. In this study, the hillslope response to river incision is quantitatively examined using new high resolution topographic data sets (lidar and photogrammetry) in combination with 3 field mapping and tephrochronology. Hillslopes are found to be coupled to river incision and adjusted to rapid incision through the initiation and reactivation of deep-seated landslides. In the erodible marine sedimentary rocks of the terrestrialWSS, post-incision deep-seated landslides can occupy over 30% of the surface area. Many of these slides show evidence of multiple “nested” failures and landslide reactivation. The ages of tephra cover beds identified by electron microprobe analysis show that following an initial 4,000 to 5,000 year time lag after the initiation of river incision, widespread hillslope adjustment started between the deposition of the ca. 13,600 cal. yr BPWaiohau tephra and the ca. 9,500 cal. yr BP Rotoma tephra. Tephrochronology and geomorphic mapping analysis indicates that river incision and deep-seated landslide slope adjustment is synchronous between mainstem rivers and headwater tributaries. Tephrochronology further shows that many slopes have continued to adjust to channel incision into the late Holocene. Hillslope response in the catchment can involve the entire hillslope from river to ridgeline, with some interfluves between incising sub-catchments being dramatically modified through ridgeline retreat and/or lowering. Using the results of the landform tephrochronology and geomorphic mapping, a conceptual time series of hillslope response to uplift and climate change-induced river incision is derived for a timeframe encompassing the last glacial-interglacial cycle. Using the same high resolution topography datasets, in-depth field analysis, and tephrochronology, the 18,000 year sediment yield from terrestrial deep-seated landslides in theWSS is estimated in order to investigate the magnitude of hillslope response to climate-modulated, uplift driven river incision. This completes one of the first processbased millennial time-scale sediment budgets for this class of temperate maritime, active margin catchments. Fluvial and geomorphic modelling is applied to reconstruct pre 18,000 cal. yr BP topography in 141 km2 of detailed study area and the resulting volumetric estimates from 207 landslides are used to estimate deep-seated landslide sediment flux for the broader system. An estimated 10.2 km3 of deep-seated landslidederived sediment with a multiplicative uncertainty of 1.9 km3 (+9.2 km3, -4.8 km3) was delivered to terrestrial and marine sinks. This accounts for between 10 and 74% of the total mass of the terrestrialWSS budget of ca. 91,000 Mt (+37,000 Mt, -26,000 Mt). Combining the deep-seated landslide results with other studies of terrestrial sediment sources and terrestrial and shelf sinks, the estimated terrestrial source load ranges from 4 Abstract 1.2 to 3.7 times larger than the mass of sediment sequestered in terrestrial and shelf depocentres. This implies that off-shelf transport of sediment is important in this system over the last 18,000 cal. yr BP, as it is today for anthropogenic reasons. Based on the derived sediment budget, the denudation rate for the terrestrialWSS of 0.8 mm yr-1 (+0.3 mm yr-1, -0.2 mm yr-1) is indistinguishable from the average terrestrialWaipaoa late Quaternary uplift rate, indicating an approximate steady-state balance between denudation and uplift. This thesis provides a quantitative analysis of the role of deepseated landslides in an active margin catchment that is used to improve the understanding of landscape and terrestrial source-to-marine-sink sediment transfer dynamics.

Vibration in the vehicle environment has long been investigated considering the driver&#039 / s exposure. However not only drivers but also the front seat car passengers are exposed to considerable amount of vibration. In order to investigate the phenomenon, this research consisted of three stages. In the first stage of the study, model analysis has been carried out. Based on the results it has been suggested that increased damping in the lumbar area in contact with the backrest can decrease the vibration transmission. The second stage comprised of the laboratory studies. Based on the results attained from the model, waist belts filled with different fluids having different coefficients of viscosity were prepared and tested. The inclination of the backrest angle was chosen as the second parameter. The cushions having ready-made gel mediums were seen to be effective in reducing low frequency vibrations where the angle of inclination affected the response of the cushions. In the third part of the thesis, field measurements were carried out in order to confirm the results attained in the laboratory. It was observed that the inclination of backrest angle played a major role in the exposure of the passenger in fore and aft direction. The cushions proved to be effective at certain frequencies in the field, differing due to the design and the medium.

This project presented a biomechanical model of the lumbosacral spine and pelvis, including novel methodologies associated with the measurement of human mechanics. This research has, for the first time, produced accurate three-dimensional geometric models of the human skeleton from living subjects using magnetic resonance imaging technology, enabling the prediction of physiological muscle action within individuals. The model was used to examine changes in the mechanics of the lumbopelvic musculoskeletal system between the standing and seated postures due to the increasing prevalence of the seated posture in the work and home environment. The outcomes of this research included a novel bone wrapping algorithm used to describe the effect of muscle-bone interactions. a novel method for creating three-dimensional in vivo spinal reconstructions using MRI, three dimensional in vivo helical axis measurements and subject specific normalised moment data.

The primary objective of this study is to provide a greater understanding of the tectonic evolution of the Warburton, Cooper, Eromanga and Lake Eyre Basins in central Australia. However, this study additionally attempts to provide a greater understanding of lineaments. This study compares lineament data with a traditional tectonic analysis in order to evaluate lineaments and to best understand the tectonic evolution of the region.