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Monolithic integration of direct-bandgap III-V materials onto Si is an attractive approach to realise on-chip light sources for Si-based photonic integrated circuits (PICs). However, the direct epitaxy of III-V materials onto Si substrates introduces a high density of crystalline defects such as threading dislocations (TDs), antiphase boundaries (APBs) and micro-cracks, which serve as non-radiative recombination centres and hence significantly degrade the performance of laser devices. This thesis aims to reduce the impact of these critical defects on molecular beam epitaxy (MBE) grown, high-performance InAs/GaAs quantum dot (QD) lasers on Si substrates, and hence to provide practical on-chip light sources for Si-based PICs. A thin Ge buffer layer is first proposed to replace a part of thick GaAs to solve the micro-crack issue while keeping the laser performance unaffected. Ge buffer layers are optimised in terms of annealing methods, thickness and doping materials to obtain low TD density. Based on the optimised Ge/Si virtual substrate, an all-MBE grown InAs/GaAs QD laser device has been demonstrated with an overall thickness (5.4 µm) close to the cracking threshold (~5 µm). Lasing up to 130 °C is obtained for this laser. A novel method has been developed in Chapter 4 to suppress the formation of APBs during the epitaxy of polar III-V on non-polar Si. It enables the monolithic integration of InAs/GaAs QD lasers on microelectronic standard nominal Si (001) substrates. The parallel Si single-atomic-height (S) steps formed on the Si buffer layer reorganise the nucleation of APBs into an ordered distribution and promote sufficient self-annihilation of APBs in the subsequent GaAs growth. Finally, a 1 µm-thick APB-free GaAs grown on Si (001) substrate has been demonstrated. Based on this APB-free GaAs/Si (001) platform, an all-MBE grown high-performance InAs/GaAs QD laser has been fabricated with a low threshold current density (80 A/cm2 ) and a high operating temperature (120 °C). Moreover, studies related to APB nucleation, propagation, and interaction with TDs are presented in Chapter 5, which provides insights for further optimising high-performance InAs/GaAs QD lasers grown on Si (001) substrates.

Digital imaging plays an essential role in many aspects of our daily life. However due to the hardware limitations of the imaging devices, the image measurements are usually inpaired and require further processing to enhance the quality of the raw images in order to enable applications on the user side. Image enhancement aims to improve the information content within image measurements by exploiting the properties of the target image and the forward model of the imaging device. In this thesis, we aim to tackle two specific image enhancement problems, that is, single image super-resolution and image completion. First, we present a new Deep Analysis Dictionary Model (DeepAM) which consists of multiple layers of analysis dictionaries with associated soft-thresholding operators and a single layer of synthesis dictionary for single image super-resolution. To achieve an effective deep model, each analysis dictionary has been designed to be composed of an Information Preserving Analysis Dictionary (IPAD) which passes essential information from the input signal to output and a Clustering Analysis Dictionary (CAD) which generates discriminative feature representation. The parameters of the deep analysis dictionary model are optimized using a layer-wise learning strategy. We demonstrate that both the proposed deep dictionary design and the learning algorithm are effective. Simulation results show that the proposed method achieves comparable performance with Deep Neural Networks and other existing methods. We then generalize DeepAM to a Deep Convolutional Analysis Dictionary Model (DeepCAM) by learning convolutional dictionaries instead of unstructured dictionaries. The convolutional dictionary is more suitable for processing high-dimensional signals like images and has only a small number of free parameters. By exploiting the properties of a convolutional dictionary, we present an efficient convolutional analysis dictionary learning algorithm. The IPAD and the CAD parts are learned using variations of the proposed convolutional analysis dictionary learning algorithm. We demonstrate that DeepCAM is an effective multi-layer convolutional model and achieves better performance than DeepAM while using a smaller number of parameters. Finally, we present an image completion algorithm based on dense correspondence between the input image and an exemplar image retrieved from Internet which has been taken at a similar position. The dense correspondence which is estimated using a hierarchical PatchMatch algorithm is usually noisy and with a large occlusion area corresponding to the region to be completed. By modelling the dense correspondence as a smooth field, an Expectation-Maximization (EM) based method is presented to interpolate a smooth field over the occlusion area which is then used to transfer image content from the exemplar image to the input image. Color correction is further applied to diminish the possible color differences between the input image and the exemplar image. Numerical results demonstrate that the proposed image completion algorithm is able to achieve photo realistic image completion results.

INTRODUCTION: Stroke is the leading cause of disability worldwide and a major cause of death, its mortality is second only to cardiovascular disease. The role of intracranial stents is essential in the management of stroke, but current intracranial stents display unwanted side effects resulting in allergic reactions, chronic inflammation and thrombosis followed by re-narrowing of the blood vessels. Surface modification strategies are now in demand to improve tissue interactions at the neurovascular interface. This study aims to develop a novel nano-surface coating technique to create reproducible nano-metric scale surface topographies and to apply it as a post-modification of intracranial stents, to promote in-situ endothelization. METHODOLOGY: We develop a low-cost procedure to create polymeric nanoisland coating by enduring phase separation. SEM and AFM were applied to study the topography profile of the coating. Hemocompatibility tests were performed to assess the thrombogenicity of the coating. HUVECs were also cultured on the coating to assess the toxicity and biocompatibility of the coating. SEM was carried out on the cells after culturing on the coatings to reveal the material-cellular interaction on the coating surface. Coating procedure was then optimised to be applied onto bare metal stents (BMSs). The coated BMSs were mounted onto balloon catheters, sterilised with Ethylene Oxide and implanted into a pilot rabbit model for 28-days. Patency data was collected, histological analyses were then performed following termination. RESULTS: SEM and AFM confirmed the presence of a uniform coating layer with nano-islands of 20 nm in height and 100 nm in radius. Hemocompatibility tests revealed the coating was inert towards human blood component and showed lower thrombogenicity than control. HUVECs also demonstrated enhanced growth and proliferation on the coating. SEM morphology study hinted that the nano-islands on the coating could be promoting the HUVECs migration and growth by providing contact guidance to the cells. We successfully apply the coating onto commercially available BMSs. Delamination study revealed only minimal surface cracks on the optimised coated BMSs, suggesting the coating remained stable. Finally, two coated BMSs were implanted into two healthy New Zealand White rabbits, and their patency was maintained over 28 days. CONCLUSION: We have developed a simple and reproducible polymeric nano-island coating that showed low thrombogenicity and promote in-situ endothelization for vascular stents. Preliminary in vivo data suggest non-inferior early patency compared to uncoated BMSs with no apparent adverse effect.

Highway infrastructure development in Yunnan Province remains a top priority for the Chinese Government, the aim is to improve access to neighbouring countries and support economic growth and social development in the province. While the social and economic benefits of highway infrastructure projects are indisputable, sustainable performance still leaves room for improvement in Yunnan. In an effort to promote a more sustainable approach to decisions relating to highway infrastructure projects, this research develops a model to assess sustainability in highway infrastructure projects in Yunnan Province. The research results indicate that although China has made great progress in sustainable development, and studies have suggested various frameworks for evaluating sustainability in highway infrastructure projects, an effective assessment model is not available for the local context of Yunnan. Therefore, this research builds an indicator-based assessment model for highway infrastructure project sustainability by addressing local conditions. The data used for analysis in this research is collected from questionnaires and interviews of three groups of experts in Yunnan, including government officers, academic professionals, and construction engineers in the construction industry. Data collected by questionnaires is used to determine the indictors, and the Analysis Hierarchy Process (AHP) method is used to assign indicators weightings. The opinions from the experts' interviews are used to refine the model, and the content analysis is used to analyse interview data. This research identifies a highway project in Yunnan as a case study to test the applicability of the developed model, and the results indicated that the sustainability assessment model for highway infrastructure projects in Yunnan is reasonable. However, in practice, it faces extensive challenges in assessing sustainability in highway infrastructure projects in Yunnan. This study demonstrates the importance of sustainability assessment and strives to build a comprehensive indicator system with consideration of all influential factors, as a positive step towards dealing with these challenges.

Using piezoelectric materials to harvest energy from human movement provides a potential power source to wearable devices and electronic textiles in everyday life. Two common comerical piezoelectric material: lead zirconate titante (PZT) and polyvinylidene fluoride (PVDF) are unsuitable for human body energy harvesting applications due to the high hardness and fragility of PZT and the low piezoelectric coefficients of PVDF. Ferroelectret is a thin polymer foam that can store electric charges in its internal voids, have strong piezoelectric properties and low elastic modulus which would make them very desirable for human body energy harvesting. The piezoelectricity of ferroelectrets originates from the combination of the internally stored charges and the cellular structures. However, the resulting pizoelectric properties of commercialized ferroelectrets are limited by the random individual void geometry and irregular overall cellular structure due to its existing fabrication processes. This work develop a numerical model using finite element analysis (FEA) approach to design and optimize the structure of ferroelectret during fabrication. Based on the models, we used polydimethysiloxane (PDMS) materials to fabricate ferroelectrets with different internal structures. The fabrication is done by casting method with 3D-printed moulds and silicon moulds produced using MEMS processes. The piezoelectric properties of fabricated PDMS ferroelectret are investigated to further validate the accuracy of our proposed numerical model in the work. The designed PDMS ferroelectret presented a maximum piezoelectric coefficient d33 of 520 pC/N. It can provide the maximum output voltage of 13 V and average output of 2.73 μW when connected to a 65 MΩ resistive load under acompressive force of 800 N at human normal walking model. The optimization PDMS ferroelectret strucutre for human body energy harvesting is also evaluated. In addition, a method for further improving the PDMS ferroelectret piezoelectric stability is proposed.

Order Bunyavirales poses a significant threat to the agricultural industry, animal husbandry and human welfare. In response to viral infections, interferons (IFNs) trigger the expression of numerous interferon stimulated genes (ISGs) whose concerted action can potently inhibit the replication of bunyaviruses. We used a FACS-based method to screen the ability of ~500 unique ISGs from humans or rhesus macaques to inhibit the replication of Bunyamwera virus (BUNV), the prototype of both the Peribunyaviridae family and Bunyavirales order. Candidates possessing antibunyaviral activity were further examined using a panel of divergent bunyaviruses in family Peribunyaviridae, Hantaviridae, Nairoviridae and Phenuiviridae.

Understanding human behaviour in the built environment has long been a vital interest to most architects. It relates to the essential need to design a suitable building for society. Gibson's affordance theory offers an insight into the behavioural potential that the environment can provide to human beings. A number of researchers have adopted affordance theory in their studies of children's environment. While most of these studies focused on children's physical activities, the knowledge of the affordances for children's social interaction is yet to be explored in depth. By employing the focused ethnographic approach, this research conducted its fieldwork in a childcare centre in Sheffield and studied the preschool children's social interactions during their free play sessions in both the outdoor and indoor environment. The study deconstructs the childcare environment by means of behavioural affordances and demonstrates a typical taxonomy of children's social interactions in the childcare environment, followed by in-depth interpretation of case social interaction events. The study proposes a methodology to conduct focused ethnographic research in the spatial design field, and establishes an affordance correspondence framework between children's social behaviours and environmental features, and further suggests a range of design guidelines towards a children-centred, diversified, and supportive childcare environment. Following this study, further research can be expected in the area of children's environmental perception, interest, decision-making as well as affordance design in the built environment.

Re and Os are present in many crude oils in measurable abundances. The Re-Os geochronometer has successfully constrained the timing of oil generation, thermochemical sulphate reduction and thermal alteration of crude oil for petroleum systems worldwide. The Os isotope composition has also been used as an oil-source correlation tool. This thesis firstly presents two petroleum matrix-matched Re-Os measurement reference materials: the RM8505 crude oil and ~ 90 g homogeneous asphaltene powder isolated from the RM8505 crude oil. The Re-Os data are from the repeated measurements of these samples via the Carius Tube - Isotope Dilution - Negative Thermal Ionization Mass Spectrometry methodology. The normal distribution and low relative standard deviation of the abundance and isotopic data ensure them to be appropriate petroleum matrix-matched reference materials for Re-Os measurements. A Re-Os age of 66 ± 31 Ma was defined by the Duvernay-sourced oil asphaltene fractions from Western Canada sedimentary basin. This age is in excellent agreement with the main-stage hydrocarbon generation of Duvernay Formation based on basin modelling. Further, this study supports Os isotope composition as a valid oil-source tracer and the hypothesis that the oil 187Os/188Os composition is inherited from the source unit during oil generation. This study shows limited or no influence of the Re-Os systematics of crude oil through the interaction of basinal fluids. The progressively precipitated asphaltene fractions of six oil samples exhibit a decrease in Re and Os abundance, and diverse 187Re/188Os and 187Os/188Os patterns. This study proposes that Re and Os in crude oil are to be bound in multiple free compounds and such molecules occluded/absorbed in the asphaltene aggregate structure. No combination of the fractions of a crude oil can consistently yield geologically meaningful Re-Os age for all of the six oil samples, either the progressively precipitated asphaltene fractions or the asphaltenes and maltenes separated by n-alkanes. As such, obtaining geologically meaningful Re-Os dates from a single oil may not be viable for many oils.

The world is facing a serious water crisis due to rapid population growth, industrialization and climate change. Water purification using membrane technologies provides a promising solution to address this problem. This thesis investigated the feasibility of membrane technologies in a wide range of applications covering drinking water purification and wastewater treatment. Target contaminants included fluoride, natural organic matter (NOM), emerging contaminants bisphenol A (BPA) and cimetidine, and the waterborne parasite Cryptosporidium. The first part of the thesis explored the solute-solute interactions of fluoride and humic substances (HS) in order to understand the behaviour of fluoride in natural water and during membrane filtration processes. It is shown that, at low pH and high ionic strength, fluoride ions are temporarily trapped inside the structure of HS aggregates. The second part of the thesis examined the feasibility of nanofiltration (NF) and reverse osmosis (RO) in treating challenging natural waters in Tanzania containing high fluoride and NOM concentrations, with the aim to increase the availability of drinking water sources. Fluoride retention was found to be dependent on ionic strength and recovery, which was predominantly due to a solution-diffusion mechanism. NOM retention was independent of water matrices but was governed by a size exclusion mechanism. NOM was observed to have a positive impact on fluoride removal. The third part of this work evaluated the on-site performance of a pilot-scale renewable energy powered membrane system in remote areas under varying solar conditions. While the technology is well established, the adaptation to remote areas is far from achieved. The system used in this study reliably produced high-quality drinking water despite of solar fluctuations. This area requires further work in terms of integration, technology adaptation and operation and maintenance schemes. The last part of the thesis reported the development of a series of novel photocatalytic polymers and tested their capabilities in removing wastewater contaminants. The photoactive polymers were highly capable of degrading BPA and cimetidine, as well as inactivating Cryptosporidium. These are very promising materials for simultaneous decontamination and disinfection of wastewater. The results obtained from this thesis provide new insights into solute-solute interactions, solute transport mechanisms, decentralized membrane system and novel membrane materials, which are hoped to contribute to advancements in current membrane technologies.

Risk communication disseminated during a food safety incident plays an important role in shaping consumer purchasing behaviour. Consumer research shows that immediately after a food safety incident the demand of indicted products falls rapidly and then starts to increase slowly when consumer confidence is restored. Another important aspect of risk communication is to understand how messages influence the magnitude of consumers' perceived risk and how this element can affect food purchasing behaviour. However, very little is known about the cognitive process that consumers undertake when markets are shocked by food scares and how perceived risk influence consumers' choices. In order to fill such a gap this study aims at understanding how people react and behave in food markets with and without a food safety incident caused by E. coli in meat products. To achieve this objective models of social psychology and economics were combined to assess how consumers' subjective probability (De Finetti's theorem on exchangeability) and psychological reactions (Protection Motivation Theory) impact on willingness to pay (WTP) of hypothetical meat products packaged with nanosensors. WTP for these products was elicited both by means of a payment card and a stated choice experiment and estimated respectively with a Tobit regression and a scale adjusted latent class model. The survey was administered in the UK between February and March 2015 and 627 respondents in the UK took part in the study. Results show that risk overestimated attitude in risk markets is influenced by sociodemographic and economic characteristics of respondents. Psychological elements and subjective probability have also different impacts in the simulated market scenarios of risk and no risk In particular, WTP for meat packaged with nanosensors varies under different psychological reactions and subjective probability fits well the identification of latent classes and consumers' choices. Marketing and policy implications of these findings are discussed.

Chloride-induced corrosion of steel in reinforced concrete structures is one of the main problems affecting their durability, but most previous research projects and case studies have focused on concretes without cracks or not subjected to any structural load. Although it has been recognised that structural cracks do influence the chloride transport and chloride induced corrosion in reinforced concrete structures, there is little published work on the influence of microcracks due to service loads on these properties. Therefore, the main objective of this research was to identify to what extent microcracks due to structural loads affect the chloride transport and chloride-induced corrosion in reinforced concrete structures and thereby make recommendations for any change of service life designs of such structures. Three stages of experiments were carried out. They were the influence of stresses and microcracks on chloride migration, diffusion, sorption and chloride-induced corrosion of steel in concrete. The main findings from this project are: chloride migration coefficients of concrete changed little when the stress level was below 50% of the ultimate stress (fu). A recovery of around 50% of the increased chloride migration coefficient was found in the case of concretes subjected to 75% of the fu when the load was removed. The influence of concrete mixes on chloride diffusion coefficient of concrete could be more significant than that of stress levels when the concrete was subjected to ponding of salt water. The role of cracks was found to be more important when the concrete was subjected to 'sorption + diffusion' compared with concrete subjected to diffusion alone. These finds suggest that the effect of microcracks is very significant for the service life of reinforced concrete structures in aggressive environments. This means that for the service life design of reinforced concrete structures in chloride exposure environments, consideration should be given to microcracks at service loads.

This thesis investigates the design, operation and use of contemporary demountable buildings, and explores how functional performance can be assessed in small-scale examples for public use alongside with their relationship to other design elements. The research focuses on three case studies that do not require a high-technology building environment or complex construction skills. Demountable buildings are defined as those that are transported in a number of parts for assembly on site. Contemporary demountable buildings respond to ecological issues, social impacts, technological innovation and economic demands. They can be used to measure a society’s development in environmental sustainability, innovation and economic growth through various forms. Small-scale demountable buildings fulfil many temporary habitation needs in diverse roles, such as non-emergency transitional housing, ephemeral exhibition buildings and seasonal entertainment facilities. The purpose of examining functional performance is to assess if, and how, the requirements of the design have been achieved. This enables project operators to address functional performance from a public perspective by reflecting on the scope and ambition of their projects. This thesis draws on existing literature to investigate previous and on-going research relating to demountable buildings, including classification, the construction process and project management. It also examines selected existing evaluation methods that cover principles, modelling and computer-based solutions from a wider research area, including Guidelines Developed by City Council and Culture Sectors; Assessment Methods in Humanitarian Response and Methods in Environmental Assessment. The research was conducted by combining both quantitative and qualitative research methods, including field research, case studies, interviews, questionnaires and group discussions. Fragmented narratives were transformed into structured evidence, identifying models of best performance in demountable buildings and developing a new method – the Evaluation Conceptual Model – for the effective evaluation and evidencing of the value of demountable buildings in the 21st century. Recommendations for adapting a suitable model to evaluate other design elements in demountable buildings and other types of moveable buildings in further research are suggested and the findings have been used to lay the foundations for a practical evaluation tool for the future.

This PhD project is a collaboration between Smart Light Devices, Ltd. in Aberdeen and Aberystwyth University on the development of such 3D laser scanners with an ultimate aim to inspect the underwater oil and gas pipes or structure. At the end of this project, a workable and full functional 3D laser scanner is to be developed. This PhD project puts a particular emphasis on the engineering and implementation of the scanner according to real applications’ requirements. Our 3D laser scanner is based on the principle of triangulation and its high accuracy over a short range scanning. Accurate 3D data can be obtained from a triangle between the scanner, camera lens, laser source, and the object being scanned. Once the distance between the scanner camera lens and laser source (stereo baseline) is known and the laser projection angle can be measured by the goniometer, all the X, Y,Z coordinates of the object surface can be obtained through trigonometry. This 3D laser scanner development involves a lot of issues and tasks including image noise removal, laser peak detection, corner detection, camera calibration and 3D reconstruction. These issues and tasks have been addressed, analysed and improved during the PhD period. Firstly, the Sparse Code Shrinkage (SCS) image de-noise is implemented, since it is one of the most suitable de-noising methods for our laser images with dark background and white laser stripe. Secondly, there are already plenty of methods for corner and laser peak detection, it is necessary to compare and evaluate which is the most suitable for our 3D laser scanner. Thus, comparative studies are carried out and their results are presented in this thesis. Thirdly, our scanner is based on laser triangulation, in this case, laser projection angle α and baseline distance D from the centre of the camera lens to laser source plays a crucial role in 3D reconstruction. However, these two parameters are hard to measure directly, and there are no particular tools designed for this purpose. Thus, a new approach is proposed in this thesis to estimate them which combines camera calibration results with the precise linear stage. Fourthly, it is very expensive to customize an accurate positional pattern for camera calibration, due to budget limit, this pattern is printed by a printer or even painted on a paper or white board which is inaccurate and contains errors in absolute distance and location. An iterative camera calibration method is proposed. It can compensate up to 10% error and the calibration parameters remain stable. Finally, in the underwater applications, the light travel angle is changed from water to air which makes the normal calibration method less accurate. Hence, a new approach is proposed to compensate between the estimate and real distance in 3D reconstruction with normal calibration parameters. Experimental results show the proposed methods reduce the distance error in 3D down to ±0.2mm underwater. Overall, the developed scanning systems have been successfully applied in several real scanning and 3D modelling projects such as mooring chain, underwater pipeline surface and reducer. Positive feedback has been received from these projects, the scanning results satisfy the resolution and accuracy requirements.

Dietary obesity after middle age is associated with insulin resistance and oxidative stress and is a major risk factor for the development of cardiovascular diseases. However it remains unclear about the effects of high-fat diet (HFD) on vascular oxidative status and endothelial function, and both of them are interactive and pivotal to the development of obesity-associated cardiovascular disease, such as atherosclerosis. Nox2 is a major source of vascular reactive oxygen species (ROS); however its role in diet-induced metabolic disorders and vascular dysfunction is unclear. Therefore, the objective of this PhD project is to investigate the role of Nox2 and oxidative stress in HFD-induced metabolic disorders and endothelial dysfunction in mice. Male C57BL/6J wild-type (WT) mice and Nox2 knockout (KO) mice at 7 month of age were fed with a HFD or a normal chow diet (NCD) for 16 weeks. Body weight, blood pressure (BP) and fasting blood samples were taken before and after diet intervention. Mice were sacrificed for assessment of aortic function ex vivo. Compared to NCD-fed mice, WT mice fed with HFD showed significant increases in body weight, fasting glucose and insulin levels with elevated lipids profiles and BP. These changes were accompanied by significant increases in nicotinamide adenine dinucleotide phosphate (NADPH)-dependent ROS production by aortas and a decrease in endothelium-dependent vessel relaxation and this was reversed back to control levels by adding superoxide scavenger tiron. Compared to WT mice, Nox2 KO mice fed with HFD has no significant increase in fasting glucose with less augmented lipids profiles and unaltered BP. The aortic NADPH-dependent ROS production remained unchanged and the endothelium-dependent vessel relaxation was well preserved. In a parallel study, HFD-fed WT mice were supplied with a Nox2 inhibitor apocynin in drinking water. Apocynin treatment significantly attenuated the HFD-induced overweight, the high lipids levels and the high BP, but had no significant effect on blood glucose levels. Apocynin treatment also preserved the endothelium-dependent vessel relaxation to acetylcholine in HFD group. To further investigate the relationship between HFD and the pathogenesis of atherosclerosis, we fed HFD to apolipoprotein E (apoE) KO mice at age of 6 weeks for 10 weeks. The HFD promoted obesity, hyperglycaemia, hyperinsulinemia, type 2 diabetes-like insulin resistance and accelerated the accumulation of low-density lipoprotein in apoE KO mice. HFD also attenuated the endothelium-dependent relaxation responses of aortas accompanied with higher BP in apoE KO mice. In conclusion, HFD increases the levels of ROS production in the vasculature. Activated Nox2 and induced oxidative stress by diet-induced obesity contribute to metabolic disorders including impaired glucose and lipids metabolism, and endothelial dysfunction. Deletion or inhibition of Nox2 attenuates these detrimental pathological progresses. Therefore, Nox2 and Nox2-derived ROS play a key role in mediating dietary obesity-related metabolic disorders and endothelial dysfunction after middle-age.

This thesis investigates the principle of integrated vehicle dynamics control through proposing a new control configuration to coordinate active steering subsystems and dynamic stability control (DSC) subsystems. The active steering subsystems include Active Front Steering (AFS) and Active Rear Steering (ARS); the dynamic stability control subsystems include driveline based, brake based and driveline plus brake based DSC subsystems. A nonlinear vehicle handling model is developed for this study, incorporating the load transfer effects and nonlinear tyre characteristics. This model consists of 8 degrees of freedom that include longitudinal, lateral and yaw motions of the vehicle and body roll motion relative to the chassis about the roll axis as well as the rotational dynamics of four wheels. The lateral vehicle dynamics are analysed for the entire handling region and two distinct control objectives are defined, i.e. steerability and stability which correspond to yaw rate tracking and sideslip motion bounding, respectively. Active steering subsystem controllers and dynamic stability subsystem controller are designed by using the Sliding Mode Control (SMC) technique and phase-plane method, respectively. The former is used as the steerability controller to track the reference yaw rate and the latter serves as the stability controller to bound the sideslip motion of the vehicle. Both stand-alone controllers are evaluated over a range of different handling regimes. The stand-alone steerability controllers are found to be very effective in improving vehicle steering response up to the handling limit and the stand-alone stability controller is found to be capable of performing the task of maintaining vehicle stability at the operating points where the active steering subsystems cannot. Based on the two independently developed stand-alone controllers, a novel rule based integration scheme for AFS and driveline plus brake based DSC is proposed to optimise the overall vehicle performance by minimising interactions between the two subsystems and extending functionalities of individual subsystems. The proposed integrated control system is assessed by comparing it to corresponding combined control. Through the simulation work conducted under critical driving conditions, the proposed integrated control system is found to lead to a trade-off between stability and limit steerability, improved vehicle stability and reduced influence on the longitudinal vehicle dynamics.

As an attempt to investigate the adoption, future emphasis and benefits derived from traditional and contemporary western-orientated management accounting practices in Chinese organisations, in particular, in state-owned enterprises and foreign joint ventures located in China, this empirical study was modeled on a similar study undertaken in Australia (Chenhall and Langfield-Smith 1998). It obtained structured information and carried out a comparison between a western capitalist developed country and an eastern socialist developing country (China), which is moving towards a market economy. The effectiveness of the adoption of management accounting practices is influenced by complex contextual factors. Based on cultural, economic, institutional, organisational and innovation theory frameworks established in the research literature, the study therefore explored a wider range of environmental factors which determined the extent to which state-owned enterprises and foreign joint ventures have employed management accounting practices, Thus, the role which joint ventures have played in the diffusion of management accounting practices in China has consequently been evaluated. A cross-sectional survey involving a postal questionnaire method of data collection was adopted. A total of 179 usable responses were received representing a response rate of 19%. The study also conducted some interviews. The results of this research indicated that management accounting practices in Chinese organisations have made considerable progress in recent years compared to previous Chinese studies (He 1997; Lin and Wu 1998; Qiao 1997). However, there is a lower usage of management accounting practices by comparison with western countries. A number of environmental factors such as external authorities, social services, advanced production and management techniques, long-standing traditional practices, the attitude of the leadership, the quality of the accounting personnel have influenced the adoption of management accounting practices in stateowned enterprises and joint ventures. This study also confirmed that joint ventures have played an important role in the diffusion of management accounting practices in China because they have in general higher adoption rates and place greater emphasis on recently developed, strategically focused, market oriented and investment appraisal techniques than state-owned enterprises. In addition, the research has reinforced some support for the findings from previous studies (Chenhall and Langfield-Smith 1998; Firth 1996; O'Connor et al. forthcoming). The study also provided some evidence supporting institutional isomorphism theory; for example, joint ventures have adjusted the management accounting systems and practices to suit the Chinese management context. The distinguishing feature of this study is that it incorporates an empirical investigation and an exploratory study in order to provide new knowledge relating to the adoption of western practices. of management accounting in China and the influence of foreign joint ventures. However, as with other studies, it has a number of limitations that need to be overcome in the future. Also future research directions are highlighted.