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The main goal of this study is to seek the effects of some risk and prognostic factors contributing to survival of female invasive breast cancer in United States. The study presents the survival analysis for the adult female invasive breast cancer based on the datasets chosen from the Surveillance Epidemiology and End Results (SEER) program of National Cancer Institute (NCI). In this study, the Cox proportional hazard regression model and logistic regression model were employed for statistical analysis. The odds ratios (OR), hazard ratios (HR) and confidence interval (C.I.) were obtained for the risk and prognosis factors. The study results showed that some risk and prognosis factors, such as the demographic factors (race and age), social and family factor (marital status), biomedical factors (tumor size, disease stage, tumor markers and tumor cell differentiation level etc.) and type of treatment patients received had significant effects on survival of the female invasive breast cancer patients.

In metropolitan areas, parking management influences drivers search time and cost for parking spaces, parking revenue, and traffic congestion. The wide deployment of wireless parking meters with sensing and communications capabilities allows the parking authority to monitor the state of each parking space in real time and optimize the parking management. In this thesis, we study state-of-the-art parking policies in smart parking systems, and show that the smart parking system needs to be "smarter". Our design goals of the smart parking systems include: (1) simplify the operations of parking systems, (2) improve drivers' satisfaction, (3) increase parking revenue, and (4) alleviate traffic congestion. Through analysis and simulations, we first show that the proposed reservation-based parking policy has the potential to achieve the above goals. We then model the behavior of both service providers and drivers in smart parking systems, and explore the dynamic pricing scheme to achieve the goals in smart parking system design. Furthermore, we design and implement a prototype of Reservation-based Smart Parking System (RSPS) that allows drivers to effectively find and reserve the vacant parking spaces. With the real time tracking of parking status via various sensing technologies, a smart parking system will dynamically update the parking price according to the physical parking status, and the parking price will affect drivers decision on parking slot selection, therefore, affect the parking status. A smart parking system can be regarded as a full-fledged cyber-physical system (CPS). Through extensive experiment based on real traffic traces and a real-world parking map, the results show that the proposed reservation-based parking policy has the potential to simplify the operations of parking systems, as well as alleviate traffic congestion caused by searching for parking. Adviser: Lisong Xu and Wenbo He

Horizontal slug flow is the most common flow regime in oil and gas pipelines. Slug flow causes severe internal corrosion problems due to its high turbulence. There is a need to study the physics and chemistry of the influences of slug flow on flow-accelerated corrosion and corrosion models. This dissertation first describes a systematically experimental investigation of mass transfer and wall shear stress in horizontal slug flow in two-phase water-gas and three-phase water-oil-gas mixtures using the Electrochemical Limiting Current technique. Water and an oil of viscosity of 2 cP were used for the liquid phase and nitrogen was used for the gas phase. Full pipe flow, plug flow, and slug flow in a 10 cm I.D. 15 m long Plexiglas TMpipe was studied. The effects of gas bubbles, the presence of an oil phase and droplets, and flow regime on average and instantaneous mass transfer coefficients in horizontal slug flow was studied. It is found that the cavitation type bubble collapsing exists in slug flow and causes an increase of up to several hundreds times the instantaneous mass transfer coefficient. The presence of the oil phase can further enhance the cavitation in slug flow. The analysis of the wall shear stress and the fracture mechanics indicates that the instantaneous wall shear stress produced by the cavitation can scrape away the corrosion film from the wall. The measured mass transfer coefficients were used to develop a mass transfer correlation highlighting the bubble collapsing effect in horizontal slug flow. A CO 2corrosion mechanistic model is developed for the prediction of corrosion rates in carbon steel pipelines experiencing horizontal slug flow. The model considers chemistry, thermodynamics, enhanced mass transfer, electrochemical reaction kinetics, and corrosion films. The model can be used to examine the effects of the slug flow characteristic parameters, temperature, and pressure on corrosion rate. The determined influence of superficial gas velocity and Froude number on corrosion rate is found. A comparison of a laboratory corrosion database and other models proposed for slug flow shows that this new CO 2corrosion mechanistic model improves the prediction of corrosion rates significantly.

Boundary layer characteristics at the trailing edge of a tiltrotor blade model were measured using a flattened pitot probe and a single hot wire. The blade was mounted in Virginia Tech Stability Wind tunnel stationary on a turntable on the wind tunnel's upper wall with the tip pointing down. The measurement point was located at 1 mm behind the trailing edge to make it possible to measure the flow near the blade surface and measure the boundary layer on both sides of the trailing edge in a same run. Mean velocity profiles were measured for a variety of Reynolds numbers and angles of attack. Turbulence intensity and spectral measurements were performed using a single hot wire at the highest Reynolds number. Conclusion was reached that both of the flattened pitot probe and single hot wire are good for boundary layer thickness measurements. Displacement thickness, which is important in trailing edge noise prediction, was calculated from the profile data and fit using an algebra expression against the tip angle of attack. Once the relationship between tip angle of attack and local effective angle of attack is obtained by lifting line theory, the results can be used in the trailing edge noise prediction code.

Capturing engineering designers’ knowledge and experience on the design of an artefact is important as this knowledge can explain why the artefact has been designed as it is, how key decisions have been made and what important issues have been considered. This tacit design knowledge enables designers to make informed decisions and improve efficiency in similar projects in the future. However, the capture and reuse of this kind of knowledge reminds to be great challenge, as it often exists in designers’ brains and is difficult to codify. Previous research is predominantly focused on the explicit knowledge of design objects that can be codified rather than the underlying tacit knowledge which explains the problem-solving strategies and decision-making processes. Additionally, engineering design is increasingly conducted in a collaborative working environment enable by the state-of-the-art information technologies. This trend has highly influenced the ways of knowledge capture and reuse, while is not well addressed by existing research. To fill these gaps, this research aims to explore new systematic methods and knowledge models for the capture and reuse of design knowledge as well as for the development of the next-generation knowledge management systems for engineering design. The development and application of these systematic methods and knowledge models requires a good understanding of the new requirements of knowledge management for engineering design, involving interdisciplinary research work across engineering and computing science. Thus, a comprehensive methodology is employed in this research, which consists of three parts. Firstly, a requirement analysis is undertaken through a literature review and a survey study to identify designers’ information needs and information-seeking behaviours within the new context. Secondly, the characteristics of engineering design knowledge are analysed, and on this basis a knowledge framework and a knowledge representation model are developed to support knowledge categorisation and representation. Thirdly, a methodology for applying these methods is analysed in order to design and develop a prototype system for implementation. Through the evaluation of both the proposed methods and system in a number of engineering design projects, the models have been proved to be capable and efficient in capturing design knowledge for better reuse, while the system not only proves the feasibility of the proposed methods but also provides the prototype of the next-generation collaborative knowledge management system.