There is no abstract available for this thesis.

Methods of predicting the dynamic forces are developed for the cases of vehicles negotiating vertical and lateral track irregularities. The bounds of validity of various models of the track are evaluated, from single degree of freedom, lumped parameter models to the case of a two layered beam on elastic foundation with a moving dynamic load. For the case of the lateral response of a vehicle negotiating a track switch, a finite element model of the track is also developed. The vehicle model developed for-the vertical case contains all the rigid body modes of a four axle vehicle for which primary and secondary suspension can be included with viscous or friction suspension damping. Solution of the vehicle/track interaction problem for these non-linear models is obtained by numerical integration, vehicle and track being connected by the non-linear wheel/rail contact stiffness. The most significant forces are shown to arise from the interaction of the unsprung mass and track resilience, with the vehicle modes also making a significant contribution, particularly in friction damped cases. For the lateral case use is made of an existing model of transient vehicle behaviour containing the wheel/rail contact non-linearities, to which track resilience is added in order to predict the track forces. The model is used to predict the forces which would be anticipated at discrete lateral irregularities such as those to be found at track switches. Once again the interaction with the track introduces modes of vibration which are significant in terms of wheel/rail forces. Comparison is made with experimental results obtained from full scale tests in the field. In one experiment the vertical track forces due to a range of vehicles negotiating a series of dipped welds in the track were measured, and in a second the lateral forces were recorded at the site of an artificially introduced lateral kink. A particular application of the results is in the prediction of the rate of deterioration of vertical and lateral geometry due to dynamic forces. This is to offer an improved understanding of the deterioration mechanism in order to influence the future design of vehicles and track to reduce maintenance costs.

The purpose of this study was to find the best robot configuration for climbing and descending stairs, in addition to traveling on flat surfaces. Candidate robot types were analyzed to find the most suitable one for further study, based on stability, size, and energy consumption. Based on these considerations, the non-variable configuration tracked robot type was selected. The basic robot parameters (minimum track size, comparison of tracks with grousers vs. tracks without grousers, track angle of attack) were determined using static analysis methods and using North American standards for the stair geometry. Dynamic analysis methods were then employed to refine the geometry and ensure the stability of the robot when climbing and descending stairs. The final design was then simulated in Matlab to profile the device's velocity, acceleration, and power consumption during the stair climbing and descending phases. A prototype robot was constructed. The results of this study show that a non-variable tracked robot can be constructed for the purpose of climbing stairs by applying static and dynamic analysis techniques to optimize a design. This study provides the groundwork for this design, which can also serve as a basis for designing robots with other configurations.

Thesis (M.S.) in Mechanical Engineering--University of Maine, 2008. / Includes vita. Includes bibliographical references (leaves 86-91).

Thesis (M.M.) Florida State University, 2005. / Advisor: Jayne M. Standley, Florida State University, College of Music. Title and description from dissertation home page (viewed 5-15-2007). Document formatted into pages; contains 36 pages. Includes biographical sketch. Includes bibliographical references.

The purpose of this study was to find the best robot configuration for climbing and descending stairs, in addition to traveling on flat surfaces. Candidate robot types were analyzed to find the most suitable one for further study, based on stability, size, and energy consumption. Based on these considerations, the non-variable configuration tracked robot type was selected. The basic robot parameters (minimum track size, comparison of tracks with grousers vs. tracks without grousers, track angle of attack) were determined using static analysis methods and using North American standards for the stair geometry. Dynamic analysis methods were then employed to refine the geometry and ensure the stability of the robot when climbing and descending stairs. The final design was then simulated in Matlab to profile the device's velocity, acceleration, and power consumption during the stair climbing and descending phases. A prototype robot was constructed. The results of this study show that a non-variable tracked robot can be constructed for the purpose of climbing stairs by applying static and dynamic analysis techniques to optimize a design. This study provides the groundwork for this design, which can also serve as a basis for designing robots with other configurations.

Includes bibliographical references. / Following recommendations laid down by a consensus conference in 1986, the policy of the Norwegian government has been to offer a routine ultrasound scan to all pregnant women at 18 weeks of gestation, i.e. in the second trimester (weeks 14-27) of pregnancy . This form of antenatal screening is also provided in other European countries, though several countries have gone further and now offer universal screening in the first trimester (weeks 1-13), between the 11th and 13th week of gestation, as well as in the second. In 2006, the Norwegian Directorate for Health contemplated a revision of its antenatal care guidelines, and in the process, sought to determine whether anexpansion of the programme to incorporate universal first trimester screening would be a rational step with regard to the anticipated extra benefits and costs. Except for a relatively small patient co-payment charge, antenatal screening is publicly financed as is the case with most other healthservices. Norway has however, a small but thriving private healthcare sector, and first trimester ultrasound scanning has been offered by private providers in recent years. The are many potential benefits of antenatal ultrasound screening and some of them are undoubtedly controversial. The information gained from a scan may, depending on its timing, assist in determining the pregnancy term, the number of foetuses in the uterus, the location of the placenta and the condition of the foetus. If the foetus is found to suffer from a particular disease, it may sometimes be treated prior to birth. Invariably however, ultrasound scanning in pregnancy is often associated with the detection of foetal anomalies or defects, such as Down syndrome, congenital heart defects or neural tube defects. The detection can in some cases lead to the pregnancy being terminated, whilst in other cases it may prepare the parents for a life with a child who may requiremore attention and care than others. This provision of information may be considered beneficial, however one may choose to act upon it, although it also invites an active decision which could induce negative feelings. On the other hand, the potential stress and anxiety involved in the screening and diagnostic process may be viewed as disadvantageous. This study will focus on two of the most important anomalies, at least in terms of the attention they are given in the literature: Down syndrome (DS) and serious congenital heart defects (SCHD).

No description available.

In the future, the performance of the railway system must be improved to accommodate increasing passenger volumes and service quality demands. Track switches are a vital part of the rail infrastructure, enabling traffic to take different routes. All modern switch designs have evolved from a design first patented in 1832. However, switches present single points of failure, require frequent and costly maintenance interventions, and restrict network capacity. Fault tolerance is the practice of preventing subsystem faults propagating to whole-system failures. Existing switches are not considered fault tolerant. This thesis describes the development and potential performance of fault-tolerant railway track switching solutions. The work first presents a requirements definition and evaluation framework which can be used to select candidate designs from a range of novel switching solutions. A candidate design with the potential to exceed the performance of existing designs is selected. This design is then modelled to ascertain its practical feasibility alongside potential reliability, availability, maintainability and capacity performance. The design and construction of a laboratory scale demonstrator of the design is described. The modelling results show that the performance of the fault tolerant design may exceed that of traditional switches. Reliability and availability performance increases significantly, whilst capacity gains are present but more marginal without the associated relaxation of rules regarding junction control. However, the work also identifies significant areas of future work before such an approach could be adopted in practice.

<p>This thesis deals with knowledge management at companies in the Falun-Borlänge region. The purpose is to create better understanding of which path companies have chosen and why, respectively. A qualitative survey seeks to discover if companies have chosen IT track or people track. This is a practical and useful model for an evaluative study. In the same context, a number of important models for evaluating knowledge management are presented.</p><p>The result shows that the companies provide a multitude of training within several frameworks. Education is mostly provided in a traditional manner but there are many examples of interactive state-of-the-art training. Furthermore, most of the companies primarily focus upon people and processes, but some focus at technical facilities as well. In some cases are the technical frameworks used for support of core processes.</p>