Design of Power Receiving Units for 6.78MHz Wireless Power Transfer Systems

In the last decade, the wireless power transfer (WPT) technology has been a popular topic in power electronics research and increasingly adopted by consumers. The AirFuel WPT standard utilizes resonant coils to transfer energy at 6.78 MHz, introducing many benefits such as longer charging distance, multi-device charging, and high tolerance of the coil misalignment. However, variations in coil coupling due to the change in receiving coil positions alter the equivalent load reactance, degrading efficiency. In recent studies, active full-bridge rectifiers are employed on WPT receivers because of their superior efficiency, controllability, and ability to compensate for detuned WPT networks. In order to take advantage of those characteristics, the rectifier switching actions must be synchronized with the magnetic field. In the literature, existing solutions for synchronizing the active rectifier in WPT systems are mostly not reliable and bulky, which is not suitable for small receivers. Therefore, a frequency synchronous rectifier with compact on-board control is proposed in this thesis. The rectifier power stage is designed to deliver 40 W to the load while achieving full zero-voltage switching to minimize the loss. The inherent feedback from the power stage dynamics to the sensed signal is analyzed to design stable and robust synchronization control, even at a low power of 0.02 W. The control system is accomplished using commercial components, including a low-cost microcontroller, which eliminates the need for bulky control and external sensing hardware. This high power density design allows the receiver to be integrated into daily consumer electronics such as laptops and monitors. Finally, a wide-range and high v resolution control scheme of the rectifier input phase is proposed to enable the dynamic impedance matching capability, maintaining high system efficiency over wide loading conditions. In addition, to increase the WPT technology adoption to low-power consumer electronics, a small wireless receiver replacing conventional AA batteries is developed. This receiver can supply power to existing AA battery-powered devices while providing the benefit of WPT technologies to consumers

Modality markers and politeness strategies in British and American ambassadorial speeches: A corpus-based approach

This study investigates modality markers used as expressions of politeness in British and American ambassadorial speeches via a corpus-based method. Results of the research reflect the semantic and pragmatic perspectives of modality markers on the theories of modality and politeness. Although modality and politeness are the central topics in a wide range of studies, the two domains have been discussed separately and their relationship has not been empirically investigated. Moreover, there has been no study on modality markers in British and American discourse, nor has the use of modality markers in British and American ambassadorial speeches been examined. Therefore, this research examines the relation of modality to politeness via the use of British and American ambassadorial speeches. The research contributes to the practice of the discourse community with the analysis of modality markers as politeness strategies in ambassadorial speeches. The results of a comparative analysis of modality markers as speakers’ politeness strategies collected in ambassadorial speeches reveal that American and British ambassadors are strikingly different in their frequency of modality markers expressing particular politeness categories. American ambassadors use more modality markers expressing positive politeness strategies such as paying attention to hearers, expressing strong commitment, hedging on hearers’ positive face, expressing optimism, complimenting to mitigate the force of comments, making claims and minimising the imposition of face-threatening acts. British ambassadors, however, employ more modality markers expressing negative politeness strategies such as hedging on negative face-threatening acts, expressing hypotheses, expressing humbleness and mitigating the force of obligation. Therefore, this thesis claims that American ambassadors use more modality markers expressing positive politeness in terms of personal emotions and directness, while British ambassadors prefer modality markers expressing negative politeness such as tentativeness, indirectness and mitigation. It is noted that modality is represented in a range of syntactic structures and patterns other than single modal auxiliary verbs. In addition, since modality markers as expressions of politeness are culture-specific, the use of modality markers differs from one culture to another. Moreover, modality markers cannot totally be treated as hedges in intercultural communication since some modality markers which seem to be semantically similar between languages are actually different in their pragmatic functions among different cultures

A reinforcement learning based decision support system in textile manufacturing process

This paper introduced a reinforcement learning based decision support system in textile manufacturing process. A solution optimization problem of color fading ozonation is discussed and set up as a Markov Decision Process (MDP) in terms of tuple {S, A, P, R}. Q-learning is used to train an agent in the interaction with the setup environment by accumulating the reward R. According to the application result, it is found that the proposed MDP model has well expressed the optimization problem of textile manufacturing process discussed in this paper, therefore the use of reinforcement learning to support decision making in this sector is conducted and proven that is applicable with promising prospects

National Brands or Private Brands? A Regulatory Focus Perspective

Drawing on existing literature, the current research is to investigate how regulatory focus moderates the influence of two aspects of message framing, i.e., attribute framing and risky choice framing, and their interactions on customer perception measured by four components: brand attitude, attitude toward the ad, purchase intention, and willingness to pay. A conceptual model was drawn to capture four hypothetical relationships: regulatory focus and attribute framing (H1), regulatory focus and brand type (H2), brand type and attribute framing (H3), and regulatory focus, brand type and attribute framing (H4). An experiment was conducted using 430 participants and a 2 (regulatory focus: promotion versus prevention) x 2 (brand types: national versus private) x 2 (attribute framing: hedonic versus utilitarian) between-subjects factorial design was used. Two focal products were employed were shampoo and shoes. Two brands were used for shampoo: Head & Shoulders (national) and CVS (private), and two brands for shoes: Nike (national) and Starter (private). The results showed that out of 4 hypotheses, only H2 was supported for shoes and the remaining hypotheses were not supported. However, follow up contrasts for this supported hypothesis indicated that national brands are more persuasive than private brands no matter whether customers are promotion or prevention oriented, or H2a was supported, but H2b was not. The current study attempted to address an increasing heated topic “How to create a positive attitude toward private brands?” which has been discussed in brand management literature. It answered this question by proposing a conceptual model reflecting the persuasion mechanism in which customer perception is moderated by regulatory focus and testing hypothesese using 430 participants. Although many of the results of the study were consistent with those of previous studies, the current research provided critical points that were not found in the previous literature, for instance, promotion oriented customers did not have higher level of persuasion while being exposed to hedonic attributes than to utilitarian attributes. Additionally, the study provides better insights into how regulatory focus moderates the effects of attribute framing on customer perception. It also has implications for both academicians and practitioner

College Students\u27 Choice Criteria of Retail Banks

The purpose of this research is to develop a scale identifying American college students’ choice criteria of retail banks. It is an exploratory study that complements extant studies on retail bank selection. The reliability of the scale was assessed using exploratory factor analysis and serves as a prelude to further empirical validation analysis. The results present four distinct factors important in the selection of retail banks, namely, convenience , competence”, “recommendation by parents and free banking - no bank charges . It concludes by discussing managerial contributions, limitations and future research directions

Market Orientation: Do Schools Care?

The primary objective of the paper is to validate the concept of market orientation adapted from related literature and apply it into the academic institution. It also examines the effects of market orientation as a 2nd order factor on student satisfaction in an academic setting. The revised scale validated through both EFA and CFA has a good fit. And the empirical results show that the degree to which students are satisfied with their choice of the school depends significantly on how market oriented the school is. Through a structured process of scale refinement and validation, the revised MO model improves substantially as opposed to the full model adapted from Matsuko et al. (2000). It produces better fit and the difference of chi square values between two models is statistically significant (Δχ2 (74) = 262.091), proving the revised scale is superior to the original one, therefore better representing MO construct in the universities. This study succeeds in applying market orientation construct in a special service domain where all intelligence related activities are incorporated to address different aspects of market orientation in the academic environment. Content validity has a better representation of the meaning of items specifically designed to accommodate the nature of the relationship between students and the school. This proposed scale consists of three distinct 1st order subscales as components of the broad 2nd order market orientation construct. Empirical results indicate three 1st order subscales covary with the 2nd order factor and the covariance is represented by statistically significant path coefficients. This higher order model produces acceptable fit indices. With regard to the structural model, the new scale is statistically and positively related with student satisfaction measure, indicating the fact that market orientation is an important factor that substantially leads to higher student satisfaction. In other words, if schools know how to apply market orientation strategy effectively, students become more satisfied with the decision they make when selecting a school for their higher education. Through the findings in measurement approach and structural approach, it is suggested that the revised scale can be used appropriately in the academic environment as an antecedent of student satisfaction

Effects of Market Orientation on University Brand Equity

Given the propensity of brand equity to act as a good information resource and performance evaluation system for market-oriented universities, the current study proposes that market orientation is positively correlated with brand equity in an academic institution where brand equity is operationalized by four dimensions: perceived quality, brand awareness, brand association, and brand loyalty. This study used open ended interviews to investigate brand equity concept in an educational environment. This method was designed to get individual observations of brand equity from the leaders of colleges and schools. Three Deans and Associate Deans were invited to participate in face-to-face open-ended discussions . Since it was the open-ended interview, the interviewees had opportunities to express their ideas about university brand equity and specific features that make brand equity in an academic setting different from that in a corporate setting. Based on extensive experiences in management, ideas of the university leaders set a solid foundation for establishing the right brand equity concept used in an academic setting. The findings of the study showed that there was a strong connection between market orientation and university brand equity. It seems reasonable to assume that these relationships should be positive because, like a business, universities attempt to implement marketing strategies in order to build a strong brand name in the marketplace, differentiating themselves from the others in a competitive environment, and attracting more students