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The literature on buyer-supplier relationships suggests that supplier responsiveness is a critical driver for buyer firm responsiveness and also the entire supply chain's responsiveness. Beyond documented contracts, the social interactions and socially embedded relationships can also help buyer firms to manage their suppliers' responsiveness. Leadership has been regarded as an important antecedent of social interactions and exchange relationships, but most studies in inter-organizational leadership have only been carried out in a small number of areas. Previous studies of inter-organizational leadership have not dealt with limitations of applying traditional leadership styles to the inter-organizational context. This thesis answers this lacuna by examining the effect of authentic leadership on supplier responsiveness. A survey with a sample of 224 supplier firms operating in China was conducted, covering a broad spectrum of industries, firm size, and ownership structures. Data management and analysis were mainly performed using SPSS 25. The results show that buyer authentic leadership is positively related to justice perceptions of suppliers, and further influences supplier responsiveness. Moreover, the findings show that the positive relationships between buyer authentic leadership and justice perceptions are enhanced when suppliers operate in intensively competitive markets. While this positive relationship between buyer authentic leadership and perceived procedural justice is weakened in the face of a high level of dependence asymmetry within a buyer-supplier relationship, the positive relationship between buyer authentic leadership and justice perceptions is not moderated by dependence asymmetry. This thesis expands the existing knowledge about the role of authentic leadership in the channel context. First, leadership has not been studied well in the dyadic relationship. Only a few studies have focused on the effect of traditional leadership shown by a focal firm on influencing the entire supply chain. This thesis is an important addition to the current focus on traditional leadership styles in managing buyer-supplier relationships by unveiling that authentic leadership shown by buyers affects supplier responsiveness. Second, this thesis further reveals the mechanism through which buyer authentic leadership can enhance supplier responsiveness by examining the mediating roles of perceived procedural justice and distributive justice in dyadic relationships based on social exchange theory. Third, this thesis enriches previous research, which posits authentic leadership is a favourable driver of organizational performance. This thesis develops an extensive model by revealing the context in which buyer authentic leadership is most effective in enhancing supplier responsiveness. From a managerial perspective, this thesis suggests that buyers should practice authentic leadership in relationships with their suppliers by showing care about the situations of suppliers, transparency in exchanges and interactions, and a standard of ethics. In doing so, suppliers feel treated in a respectful way, in return, they will be responsive to the buyer firms' demands and requirements. Moreover, it is imperative for buyers to enhance perceived procedural justice and distributive justice in the buyer-supplier relationship, with particular attention to perceived procedural justice because perceived procedural justice could bring up suppliers' perceptions of distributive justice. Finally, buyers should take the external environment (e.g., the markets where suppliers operate) and inter-firm structure (e.g., dependence asymmetry) into consideration when rationalizing the use of authentic leadership to enhance supplier responsiveness.

This thesis investigates the computer vision application of live fish recognition, which is needed in application scenarios where manual annotation is too expensive, when there are too many underwater videos. This system can assist ecological surveillance research, e.g. computing fish population statistics in the open sea. Some pre-processing procedures are employed to improve the recognition accuracy, and then 69 types of features are extracted. These features are a combination of colour, shape and texture properties in different parts of the fish such as tail/head/top/bottom, as well as the whole fish. Then, we present a novel Balance-Guaranteed Optimized Tree with Reject option (BGOTR) for live fish recognition. It improves the normal hierarchical method by arranging more accurate classifications at a higher level and keeping the hierarchical tree balanced. BGOTR is automatically constructed based on inter-class similarities. We apply a Gaussian Mixture Model (GMM) and Bayes rule as a reject option after the hierarchical classification to evaluate the posterior probability of being a certain species to filter less confident decisions. This novel classification-rejection method cleans up decisions and rejects unknown classes. After constructing the tree architecture, a novel trajectory voting method is used to eliminate accumulated errors during hierarchical classification and, therefore, achieves better performance. The proposed BGOTR-based hierarchical classification method is applied to recognize the 15 major species of 24150 manually labelled fish images and to detect new species in an unrestricted natural environment recorded by underwater cameras in south Taiwan sea. It achieves significant improvements compared to the state-of-the-art techniques. Furthermore, the sequence of feature selection and constructing a multi-class SVM is investigated. We propose that an Individual Feature Selection (IFS) procedure can be directly exploited to the binary One-versus-One SVMs before assembling the full multiclass SVM. The IFS method selects different subsets of features for each Oneversus- One SVM inside the multiclass classifier so that each vote is optimized to discriminate the two specific classes. The proposed IFS method is tested on four different datasets comparing the performance and time cost. Experimental results demonstrate significant improvements compared to the normal Multiclass Feature Selection (MFS) method on all datasets.

With increased use of mobile phones that support mobile commerce, there is a need to examine the authentication of users. The password-based authentication techniques are not reliable with many passwords being too simple. A biometric authentication system is becoming more commonplace and is widely used in security fields because of its special stability and uniqueness. Within this context, the researcher has developed a fuzzy logic based multi-modal biometric authentication system to verify the identity of a mobile phone user. The research presented in this thesis involves three parts of work. Firstly, a model to support the authentication of mobile commerce has been proposed. Within this model, a number of different authentication levels have been defined in the system which sought to achieve the balance between usability and security. Secondly, the researcher has developed a multi-modal biometric authentication system which involves typing behaviour recognition, face recognition and speaker recognition techniques to establish the identity of the user on the mobile phone. However, there are some issues with deterministic biometric authentication systems. Because of this, a fuzzy logic model which can determine the transaction risk in m-commerce and the recognition result from biometric authentication engine has been built. In the experimental stage, the researcher simulates a mobile commerce environment. At one extreme, users will just want to obtain the item and not enter any identity. They are prepared to accept the low level of risk when the transaction is of low value. On the other extreme for a high value transaction users will accept multiple levels of security and would not want the transaction to go through without any checking. The experimental results showed that the fuzzy logic based multi-modal authentication system can achieve a low equal error rate (EER) of 0.63%, and by using the fuzzy logic model, it can effectively reduce the false rejection rate (FRR). There is also a reduction in the environmental influence in the fuzzy logic based biometric authentication. There are three contributions of the thesis: firstly, this research has proposed a model to support the authentication in mobile commerce. Secondly, a multi-modal biometric authentication system was developed. Another major contribution is the development of a fuzzy logic based multi-modal biometric authentication system which is able to overcome the issues of deterministic biometric systems. Overall, the results gained in this thesis prove that using the multi-modal biometric authentication system, itis possible to establish the identity of the user on a mobile phone. The fuzzy logic based authentication model can make the multi-modal biometric system more accurate, and also reduce the influence of external environmental factors. A holistic interpretation of the research indicated that the mobile security and smart system can help mobile commerce become more secure and more flexible in future.

The thesis describes the design and fabrication of a monolithically integrated GaAs/AlGaAs multiple quantum well (MQW) structure two-section tunable laser, using the quantum confined Stark effect (QCSE) as the tuning mechanism. In contrast to carrier induced effect (CIE) tuned lasers, the QCSE tuned laser provides intrinsically uniform optical frequency modulation (FM) sensitivity over the modulation bandwidth of the device. First, through ridge waveguide modelling and QCSE induced refractive index change analysis, a suitable two-section ridge waveguide laser structure, having the optimised number of quantum wells, is designed. Second, as the tuning mechanism requires an applied electric field, a reverse biased p-i-n structure needs to be integrated with the forward biased laser gain section; therefore, possible isolation schemes to isolate the gain and tuning sections electrically while retaining a single optical cavity are investigated. Wet and dry etches, H+ and O+ implantation to achieve electrical isolation are studied. Third, since it is always desirable to have low residual intensity modulation for a frequency tuned laser, a study on impurity-free vacancy diffusion techniques has been carried out to investigate suitable methods of producing a transparent tuning section. A fabrication process to achieve ~10nm band-gap detuning between gain and tuning section, while maintaining good laser performance, is described. Finally, as laser parasitic parameters limit achievable laser modulation bandwidth, low parasitic laser structures have been designed. An air-bridged laser built on a semi-insulating substrate and a polyimide planarised laser built on an N+ substrate are fabricated successfully, with their tuning section band gap blue shifted relative to that of the gain section. Good CW single mode operation with less than l0MHz linewidth is achieved. FM response uniformity within ±3dB over the bandwidth 30kHz to 6GHz has been achieved, with an intensity modulation index less than 0.1 for 5.5GHz peak optical frequency deviation. The fabricated band gap shifted low parasitic tunable lasers have been characterised extensively, to assess the static and dynamic laser performance and identify the factors influencing pure QCSE tuning. A comparison study has been carried out to compare the tuning merits of this laser and traditional CIE tuned lasers. Further improvements are suggested to achieve better tuning performance and the design for a QCSE tuned laser based on the InP/InGaAsP material system is outlined.

This dissertation describes research focused on the synthesis, polymerization and applications of cationic aminooxy lipids. An efficient and convenient method was developed to stabilize liposomes using 'click chemistry'. The 'click stabilized liposomes' are fortified via covalent crosslinks generated between aldehyde and aminooxy functionalities in the lipid bilayers. Compared to untreated liposomes (i.e., no lipid-lipid bonding), the 'click' stabilized liposomes are considerably more stable against surfactant-mediated liposome disruption or serum-mediated liposome aggregation. Stabilized liposomes also can react with 'clickable' targeted ligands on the liposome surface for specific organ (e.g. breast cancer cells or liver) targeting. In this thesis, I have explored the feasibility of using the click stabilized liposomes in three different applications: i) colonic targeted delivery ii) gene vector iii) enzyme nanoreactor. This dissertation is divided into six chapters. Chapter 1 gives a review of liposomes and liposome stabilization. Chapter 2 describes the synthesis and characterization of cationic aminooxy compounds 2.1 and 2.2 as the headgroup domains of prototype lipids. Chapter 3 describes the synthesis, characterization and hydrolysis of cationic aminooxy enol ether lipids 3.1 and 3.2. The liposomes formulated from lipid 3.2 were stabilized using a pH-triggered lipid polymerization strategy. Chapter 4 describes the synthesis and characterization of a variety of aminooxy lipids and dextran polyaldehydes (DPAs). The liposomes formulated from lipids 4.1 were stabilized by simply mixing with DPAs. The resultant 'click' stabilized liposomes have potential applications such as drug carriers for colonic targeted delivery and as nano-reactors. Chapter 5 focuses on applying 'click' stabilized liposomes as gene carriers. The initial results of in vitro gene transfection revealed that the stabilized lipoplexes formulated from lipid 4.1 successfully transfected MFC-7 cells, but with lower transfection potency. A liver-targeted ligand 5.2 based on lactose was synthesized for future in vivo gene transfection applications. Chapter 6 details all experimental procedures and approaches used for compound characterizations.

Chinese-American parents are parenting within two cultures: the mainstream American culture and their heritage Chinese culture. This study examined parental cultural orientations toward the American and Chinese cultures, and the implications for parenting practices among Chinese-American families. Parenting dimensions examined were both culture-general measures (parental warmth, punitive parenting, non-democratic parenting) and culture-specific measure (parental endorsement of family obligations). Data came from a two-wave survey of about 400 Chinese-American families (one target adolescent, mother, and father). First, within each wave, the study examined the concurrent relationships between parenting practices and adolescent depressive symptoms. Second, this study examined, concurrently and longitudinally, whether parental cultural orientations were associated with parenting practices both directly and indirectly through two mediating factors: parents' bicultural management difficulty and depressive symptoms. Analyses were conducted separately for mothers and fathers. First, study findings showed that parenting practices characterized by higher levels of warmth, strong endorsement of family obligations, and lower levels of punitive and non-democratic behaviors were associated with fewer depressive symptoms in adolescents. Second, the study demonstrated significant direct relationships between both Chinese and American orientations and parenting practices. While American orientation was related to effective parenting (more warmth, low punitiveness, low non-democratic parenting), Chinese orientation was related to effective parenting (more warmth, low non-democratic parenting, strong endorsement of family obligations) as well as ineffective parenting (high punitiveness). This study also showed that parents' bicultural management difficulty and depressive symptoms mediated the relationships between acculturation and culture-general parenting measures (warmth, punitiveness, and nondemocratic parenting). It was through these two mediators (bicultural management difficulty and parental depressive symptoms) that (1) Chinese orientation was related to less warmth, high punitive and non-democratic parenting and (2) American orientation was related to more warmth, low punitive and non-democratic parenting. Lastly, there was some evidence of longitudinal relationships (father's American orientation at w1 predicted more warmth at w2; mother's American orientation at w1 predicted low punitiveness at w2 through the mediating factors of bicultural management difficulty and depressive symptoms at w1). The study suggests that parental psychological maladjustment is a promising area for interventions to promote parenting and adolescent development among ChineseAmerican families.

This study examined whether maternal employment influences three aspects of children's television use: total amount of television, television content, and children's co-viewing patterns. The study also examined whether the associations between maternal employment status and children's television use would vary by family structure or day type (weekday vs. weekend day). The analyses were conducted separately for children who were not attending kindergarten/school and children who were attending kindergarten/school. The findings indicate that for children who were not attending kindergarten/school, whether mothers worked or not was not related to how much these children watched. However, there were significant differences in children's co-viewing patterns. Children of part-time working mothers spent less time coviewing with mother or other adult(s) but more time watching television without any adult present when compared with children of unemployed mothers and children of fulltime working mothers. Overall, the relationships between maternal employment status and children's television use did not differ much by family structure or day type for these children who were not attending kindergarten/school. Among children who were attending kindergarten/school, children of part-time working mothers watched more TV in total, watched more violent TV, and spent more time viewing without any adult's supervision than children of unemployed mothers and children of full-time working mothers. These differences were more pronounced for single-mother families than two-parent families. The patterns of the associations between maternal employment and children's television use were similar for weekday viewing and weekend day viewing. Implications of these results were discussed.