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Improvements in railway capabilities have resulted in heavier axle loads and higher speed operations, which increase the dynamic loads on the track. As a result, railway subsidence has become a threat to good railway performance and safe railway operation. The author of this thesis provides an approach for railway performance assessment through the monitoring and prediction of railway subsidence. The InSAR technique, which is able to monitor railway subsidence over a large area and long time period, was selected for railway subsidence monitoring. Future trends of railway subsidence should also be predicted using subsidence prediction models based on the time series deformation records obtained by InSAR. Three time series prediction models, which are the ARMA model, a neural network model and the grey model, are adopted in this thesis. Two case studies which monitor and predict the subsidence of the HS1 route were carried out to assess the performance of HS1. The case studies demonstrate that except for some areas with potential subsidence, no large scale subsidence has occurred on HS1 and the line is still stable after its 10 years' operation. In addition, the neural network model has the best performance in predicting the subsidence of HS1.

The application of amorphous solid dispersions is one of the most widely used formulation strategies for the enhancement of in-vitro and in-vivo performance of poorly water-soluble drugs. However, because of their meta-stable nature, the physical stability of amorphous solid dispersions has been considered to be the main obstacle for their formulation development and commercialisation by the pharmaceutical industry. The aim of this project was to understand, predict and enhance the physical stability of amorphous solid dispersions prepared by hot melt extrusion. Four model drugs felodipine, celecoxib, fenofibrate and carbamazepine and two polymeric matrices EUDRAGIT® EPO and Kollidon® VA 64 were formulated by hot melt extrusion and spin coating into solid dispersions. A series of physicochemical characterisation techniques including MTDSC, PXRD, SEM, ATR-FTIR and AFM-LTA were used to evaluate the systems. Physical characterisation of the model drugs and polymers, prediction of drug-polymer miscibility and solubility and real-time physical stability studies under different conditions were carried out. Across the project, several key achievements were obtained. It was revealed that the physical stability of the amorphous drugs alone and the predicted processing-related apparent drugpolymer solubility were the two dominant factors controlling the physical stability of the amorphous systems. A practical method, milling, was developed to provide a more accurate prediction of processing-related apparent drug-polymer solubility. Two methods were developed to enhance the physical stability of amorphous solid dispersions: one based on formulation design, use of immiscible polymer blends and the other based on a particular type of processing, spin coating. The achievements from the project are expected to contribute to the formulation development of amorphous solid dispersions in terms of screening suitable drug candidates, selecting “safe” (physically stable) drug loadings and identification of methodologies to improve the physical stability of formulations.

With rapid urbanization rate in China, cities will use more cement, one of the most important construction materials, to build new infrastructure to satisfy the dramatically increasing urban population in the next few decades. In 2010, China’s cement industry contributed 11% of nation’s total fossil-fuel carbon dioxide emissions. However, little research has been done on studying cement use in cities, which is an essential part in order to learn the details of cities’ current cement use and to provide policy makers as well as governors with a powerful tool to organize a city’s future cement use. This thesis achieves two goals. The first one is to develop construction cement intensities for China’s cities’ infrastructure, which are classified into 9 sectors: road, public transit, building, gas supply, heat supply, solid waste disposal, wastewater treatment, storm water control, and water supply. The second goal is utilizing a bottom-up method to estimate annual cement use in three of China’s cities: Beijing, Tianjin and Shanghai, then compare the estimation result with at-scale apparent cement use data to verify the method. Our results find cement intensities in the various sectors, i.e., the cement intensity for highway, urban road, and residential building is 0.71 tons/m, 0.034 tons/m2, and 0.19 tons/m2 respectively. Our bottom-up citywide method estimates cement use in new construction to be around half (50%) of each city’s yearly total cement use (from 2004 to 2012), which is useful for evaluating the cement distribution and relevant environmental problems. The three main cement use sectors for new construction are residential building, other building, and road system (urban road, highway, subway & light rail, railway, and bridge) in these three cities. We believe that the unaccounted cement may be for maintenance of old stock, which was confirmed by conducting a first-order estimation that yield overall difference between bottom-up method of this paper and at-scale numbers from the city to be less than 15%. While cement use of residential buildings is decreasing during the past years in Beijing and Shanghai, Tianjin keeps a very stable status on cement use in this sector. Prior to this research, there is no study that shows cement use by infrastructure sectors, indicating the value of conducting bottom-up estimates.