Development of a computer simulation for scouring around bridge piers

Bridges are important and valuable items of infrastructure in modern society. They are designed to be functional and cost effective, but they must also be safe. A great many bridges cross bodies of flowing water and have supporting piers founded within the water; therefore the foundations are subject to erosion by scouring and this could lead to potential bridge failures. The aim of this research project is to develop a computer simulation of bridge pier scouring, to accurately predict the extent of potential scouring. Accurate predictions of scouring could lead to more efficient bridge designs while still maintaining the required level of safety. The project also proposes a new pier design with potential for improved scouring performance. There has previously been much research conducted on various aspects of bridge pier scouring. This includes explaining the scouring mechanism, physical experiments on pier geometries and developing prediction formulas. Most of this work has been done using scale models in a hydraulic flume tank and therefore has some limitations in transference to real scale situations. In recent years computer simulations have been developed for bridge pier scouring. They have an advantage of being able to model a situation at real scale, and can easily be altered as required. Early simulations were mainly single-phase (one fluid; water) models which require empirical sediment transport equations to predict sand movement. Multiphase (more than one fluid) simulation models are a more recent development; they model sediment transport as a granular flow. In this project Computational Fluid Dynamics (CFD) was used to develop the simulation model in ANSYS Fluent, which is a commercial software package. The model is a three-dimensional multiphase model with sand and water phases. It was based on a cylindrical control pier in a previous experiment so that known results could be used to validate the model. A new streamlined slotted pier geometry was proposed for performance testing with the model after validation. At present, development of the model does not achieve the anticipated objective of simulating local scouring around a bridge pier. The simulation of sand, as a riverbed sediment, is not realistic. Therefore the model has not been validated and is not reliable. The sand appears to behave much more like a liquid rather than a semisolid granular flow. The new pier design when tested in a two-dimensional (horizontal plane) model shows potential for reduced scouring. This is because of lower water velocity along its outer edges, compared to the cylindrical control pier. However it has not been possible to test the new pier in a three-dimensional scouring model. Future successful development with this simulation model is dependent on further research and experimentation to achieve realistic sand movement. Additional models would be required specifically to better understand modelling of sand flow and the most appropriate parameter choices to achieve it. Results from this project may offer some useful insights to other researchers, or ideas for future research projects

Italy vs. the United States: The rise and fall of socialist parties

Thesis (B.A.) in Liberal Arts and Sciences -- University of Illinois at Urbana-Champaign, 1987.Bibliography: leaves 44-46.Microfiche of typescript. [Urbana, Ill.]: Photographic Services, University of Illinois, U of I Library, [1987]. 2 microfiches (52 frames): negative

Validity of algorithms for identifying five chronic conditions in MedicineInsight, an Australian national general practice database.

Background MedicineInsight is a database containing de-identified electronic health records (EHRs) from over 700 Australian general practices. It is one of the largest and most widely used primary health care EHR databases in Australia. This study examined the validity of algorithms that use information from various fields in the MedicineInsight data to indicate whether patients have specific health conditions. This study examined the validity of MedicineInsight algorithms for five common chronic conditions: anxiety, asthma, depression, osteoporosis and type 2 diabetes. Methods Patients’ disease status according to MedicineInsight algorithms was benchmarked against the recording of diagnoses in the original EHRs. Fifty general practices contributing data to MedicineInsight met the eligibility criteria regarding patient load and location. Five were randomly selected and four agreed to participate. Within each practice, 250 patients aged ≥ 40 years were randomly selected from the MedicineInsight database. Trained staff reviewed the original EHR for as many of the selected patients as possible within the time available for data collection in each practice. Results A total of 475 patients were included in the analysis. All the evaluated MedicineInsight algorithms had excellent specificity, positive predictive value, and negative predictive value (above 0.9) when benchmarked against the recording of diagnoses in the original EHR. The asthma and osteoporosis algorithms also had excellent sensitivity, while the algorithms for anxiety, depression and type 2 diabetes yielded sensitivities of 0.85, 0.89 and 0.89 respectively. Conclusions The MedicineInsight algorithms for asthma and osteoporosis have excellent accuracy and the algorithms for anxiety, depression and type 2 diabetes have good accuracy. This study provides support for the use of these algorithms when using MedicineInsight data for primary health care quality improvement activities, research and health system policymaking and planning

Maternal Preeclampsia and Neonatal Outcomes

Preeclampsia is a multiorgan, heterogeneous disorder of pregnancy associated with significant maternal and neonatal morbidity and mortality. Optimal strategies in the care of the women with preeclampsia have not been fully elucidated, leaving physicians with incomplete data to guide their clinical decision making. Because preeclampsia is a progressive disorder, in some circumstances, delivery is needed to halt the progression to the benefit of the mother and fetus. However, the need for premature delivery has adverse effects on important neonatal outcomes not limited to the most premature infants. Late-preterm infants account for approximately two thirds of all preterm deliveries and are at significant risk for morbidity and mortality. Reviewed is the current literature in the diagnosis and obstetrical management of preeclampsia, the outcomes of late-preterm infants, and potential strategies to optimize fetal outcomes in pregnancies complicated by preeclampsia

‘Building for the Future?’ Government and Industry Responses to the Challenges of Talent Management in China Following the GFC

China suffered minimal fallout from the global financial crisis due to its burgeoning economy and ‘socialism with Chinese characteristics’ political strategy. However, despite this, its industries face enormous human resource management (HRM) challenges associated with the country's rapid economic growth. Principal amongst these HRM challenges is the need to attract and retain crucial talent. It is likely that if Chinese industry is unsuccessful in these endeavours, the future economic growth of China may be stalled, resulting in more serious long-term outcomes. This paper explores these challenges together with some possible solutions and future research directions