Wireless power transfer is becoming relevant today because of its effectiveness and convenience. It has been employed into consumer electronics such as cellular charging and electric vehicle charging. In general, inductive wireless power transfer (IPT) is mostly used for WPT. IPT requires coils and power transfer enhancing material such as ferrite to transfer power. However, Capacitive wireless Power Transfer (CPT) appears as an alternative because it requires cost effective and light metal plate couplers. Among CPT couplers, Vertical (stacked) Four-Plate Coupler (V4PC) structure offers the advantage of higher input and output self-capacitances, rotational misalignment. Safety is one of the most important aspect of wireless power transfer. This thesis proposes a solution to minimize the leakage electric field of Vertical 4-Plate Couplers (V4PCs). It does so by finding the optimum value of circuit parameters. The effectiveness of the proposed solution is shown by experimental results.

No description available.

No description available.

No description available.

No description available.

This thesis examines three important topics in corporate governance: the relationship between activist hedge funds and other institutional investors, the role of perks in the market for CEO talent, and public scrutiny and the changing nature of perks. First, I provide an in depth study of the interaction between activist hedge funds and other institutional investors. Hedge funds are more likely to target firms with high levels of institutional ownership, and demonstrate a preference for short term focused institutional investors. Hedge fund activism generates short run and long run abnormal returns without increasing stock return volatility. Regardless of investment horizon, volatility is inversely related to prior period institutional ownership. The trading behavior of institutional owners with different investment horizons is consistent with hedge fund activism creating value. These findings hold regardless of whether investment horizon is based on portfolio churn rate or type of institution. Overall, the results suggest a mutually beneficial relationship between activist hedge funds and other institutional investors. Second, in a coauthored paper with Drs. Seungijn Han and Jiaping Qiu, I provide the first comprehensive analysis on how CEOs’ wage and perks are jointly determined in a competitive CEO market. The underlying theory shows that in equilibrium, firm size, wage, perks and talent are all positively related. Perks are more sensitive than wage to changes in firm size. The more perks enhance the CEO’s productivity, the faster perks increase in firm size. Closed form solutions allow the recovery of the cost function of providing perks. I examine the determinants of CEO perquisite compensation using hand-collected information for S&P 500 companies and find consistent empirical evidence. Third, I examine the impact of public scrutiny on CEO compensation using the unique opportunity provided by the 2008 financial crisis, government support, and legislated compensation restrictions. I introduce novel data on executive perks at S&P 500 firms from 2006 to 2012. Overall, my results are consistent with increased public scrutiny having lasting impact on perks and temporary impact on wage, and with legislated compensation restrictions having temporary impact on wage. Changes in specific perks items provide evidence on which perks firms perceive as excessive and which provide common value. / Thesis / Doctor of Philosophy (PhD)

京都大学 / 新制・課程博士 / 博士(地球環境学) / 甲第23592号 / 地環博第219号 / 新制||地環||42(附属図書館) / 京都大学大学院地球環境学舎地球環境学専攻 / (主査)教授 宇佐美 誠, 教授 佐藤 淳二, 教授 山村 亜希, 准教授 徳永 悠, 教授 服部 高宏 / 学位規則第4条第1項該当 / Doctor of Global Environmental Studies / Kyoto University / DGAM

Executive compensation and its potential importance in aligning shareholder and management interests has been an extensively researched area within corporate finance. We study executive compensation while addressing several unresolved issues in the literature. In essay one, we examine CEO compensation following spin-offs. We find that CEOs are rewarded for undertaking a spin-off. Change in compensation for CEOs of spin-off firms following spin-offs is significantly higher than that for matching firms. We also find that the increase in compensation following spin-off is negatively associated with the change in firm size following the spin-off. Unlike mergers and acquisitions through which increases in executive compensation seem to be more related to size than performance, we show that CEO compensation increases following spin-offs even though spin-offs reduce firm size. In the second essay, we study changes in CEO salaries and their relation to firm performance. We document that changes in CEO salaries, which are a more permanent form of compensation change, are related to long term measures of performance. We find that CEO salaries change much more in relation to long term stock returns than short term stock returns. We also study the asymmetry in the relation between salary changes and firm performance. We find that while short term negative returns are related to changes in CEO salaries; only long term positive returns are significantly associated with CEO salary changes. This asymmetric relation is also present between total CEO compensation changes and stock returns. In essay three, we examine managerial decision horizons for target and acquirer firms in mergers and acquisitions. We find that acquirer CEOs have longer decision horizons than target firm CEOs in stock financed mergers. Acquirer CEOs in cash financed mergers and acquisitions also have longer decision horizons than target CEOs. Acquirer CEOs in both stock and cash financed mergers have significantly higher proportions of equity based compensation and significantly lower proportions of cash based compensation than target CEOs. In logistic regressions, measures of decision horizons for target and acquirer CEOs are not significantly related to the odds of stock financing in mergers and acquisitions. Our results do not offer strong support to the implications from the Shleifer and Vishny theory on the rationale for stock financed acquisitions.

No description available.

Control and diagnosis of complex systems demand accurate knowledge of certain quantities to be able to control the system efficiently and also to detect small errors. Physical sensors are expensive and some quantities are hard or even impossible to measure with physical sensors. This has made model-based estimation an attractive alternative. Model-based estimators are sensitive to errors in the model and since the model complexity needs to be kept low, the accuracy of the models becomes limited. Further, modeling is hard and time consuming and it is desirable to design robust estimators based on existing models. An experimental investigation shows that the model deficiencies in engine applications often are stationary errors while the dynamics of the engine is well described by the model equations. This together with fairly frequent appearance of sensor offsets have led to a demand for systematic ways of handling stationary errors, also called bias, in both models and sensors. In the thesis systematic design methods for reducing bias in estimators are developed. The methods utilize a default model and measurement data. In the first method, a low order description of the model deficiencies is estimated from the default model and measurement data, resulting in an automatic model augmentation. The idea is then to use the augmented model for estimator design, yielding reduced stationary estimation errors compared to an estimator based on the default model. Three main results are: a characterization of possible model augmentations from observability perspectives, an analysis of what augmentations that are possible to estimate from measurement data, and a robustness analysis with respect to noise and model uncertainty. An important step is how the bias is modeled, and two ways of describing the bias are introduced. The first is a random walk and the second is a parameterization of the bias. The latter can be viewed as an extension of the first and utilizes a parameterized function that describes the bias as a function of the operating point of the system. The parameters, rather than the bias, are now modeled as random walks, which eliminates the trade-off between noise suppression in the parameter convergence and rapid change of the offset in transients. This is achieved by storing information about the bias in different operating points. A direct application for the parameterized bias is the adaptation algorithms that are commonly used in engine control systems. The methods are applied to measurement data from a heavy duty diesel engine. A first order model augmentation is found for a third order model and by modeling the bias as a random walk, an estimation error reduction of 50 % is achieved for a European transient cycle. By instead letting a parameterized function describe the bias, simulation results indicate similar, or better, improvements and increased robustness.