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Microwave communication devices have become ubiquitous in the past decade. As an increasing number of systems compete for spectrum, guard bands have shrunk to increase bandwidth efficiency. The frequency behaviour of microwave devices is affected by thermal expansion. In order to avoid interference with adjacent bands, microwave components must exhibit high temperature-stability in most communications applications. Thermally stable materials can be used to construct temperature-stable components. However, this approach requires an expensive mass and cost trade-off. Temperature compensated aluminum resonators and filters provide major advantages in cost and mass. This work proposes that a compensating tuning screw with a temperature-dependent effective length be constructed by mounting a bimetallic compensator at the end of a mounting screw. This so-called bimetal tuning-screw can be used to produce temperature-compensated resonators and filters. There are several advantages to this approach. Compensation can be tuned by adjusting the depth of the bimetal, simply by adjusting the mounting screw. Since there are no moving parts inside the cavity or filter, and the bimetal can be plated, there are no additional sources of passive intermodulation. Also, this design is simple to implement for waveguide designs in general. In order to compensate for temperature drift, it is useful to quantify uncompensated drift. Temperature drift for a lossless linearly expanding RF component is derived from Maxwell's equations. For the lossy case, it is demonstrated that the resulting formula is approximately true, and that the quality of this approximation is excellent for practical levels of temperature range and thermal expansion. Experimental results are provided that demonstrate bimetal compensation under uniform-temperature conditions for a single aluminum resonator. Measured drift of the compensated resonator is -0.38 ppm/°C, compared to -23 ppm/°C for an uncompensated resonator. Measured drift for a bimetal-compensated 4-pole filter prototype is 2.35 ppm/°C. A method for adjusting compensation for a filter is also provided. Multiphysics simulations are used to examine power handling for bimetal-compensated filters. It is demonstrated that power-handling can be improved by reducing the effective length of the compensator to improve heat conduction to the cavity or filter.

My study investigates whether the effects of non-cash incentives on employee performance depend on when the incentive is paid and what type of task is being performed. Although firms frequently use non-cash incentives, such as merchandise, travel awards and gift cards, the effects of non-cash incentives, relative to cash incentives, are not well understood by researchers. Drawing on economic and psychology theories, I predict that the effects of incentive type (cash or non-cash) on performance depend on incentive payoff timing (near or distant future) and task type (analytic or creative). Specifically, for an analytic task, I predict and find that a cash incentive paid in the near future is most effective. For a creative task, I predict and find that a cash incentive paid in the near future and a non-cash incentive paid in the distant future are most effective. The results of my study should benefit theory and practice by identifying the most effective combination of incentive type and payoff timing for a given task type.

A model is developed for the Quanser torsion system available at Control Systems Research Laboratory at Chulalongkorn University. The torsion system is a laboratory equipment that is designed for the study of position control. It consists of a DC motor that drives three inertial loads that are coupled in series with the motor, and where all components are coupled to each other through torsional springs. Several nonlinearities are observed and the most significant one is an offset in the input signal, which is compensated for. Experiments are carried out under feedback as the system is marginally stable. Different input signals are tested and used for system identification. Linear black-box state-space models are then identified using PEM, N4SID and a subspace method made for closed-loop identification, where the last two are the most successful ones. PEM is used in a second step and successfully enhances the parameter estimates from the other algorithms.

Forced resettlement is an issue of great humanitarian concern. The disruption it brings to the lives of the people it affects cannot be fully expressed. Many of such people lose the ability of restoring their lives, never to regain it till they die. What is more alarming is when forced resettlement is not caused by conflict or natural disaster but rather conscious development projects like dams, where it is expected that great energy will be channelled towards reducing and if possible avoid the adverse impacts of such forceful resettlement as a matter of human and citizenship right. Sadly, in many instances this never happen. The aim of this study is to find out how the lessons learnt from the Akosombo forced resettlement in Ghana has been used in planning and implementing the on-going Bui forced resettlement also in Ghana. This study also tries to investigate the impacts of the planning and implementation process of the resettlement on the affected communities and households. In order to achieve the above goals, qualitative research methods were employed. The study used in-depth interviews, focus group discussions, direct and participatory observation techniques in accessing the experiences and feelings of the people involved. The informants include the institutions and professionals which undertook the forced resettlement and the affected people. The modernisation and alternative development theories were reviewed to determine which of these approaches is in practice. However, since Ghana claims it is using the World Bank Operational Policy (4.12), which is following an alternative development approach, concepts such as participation and rights are used. Additionally, concepts such as compensation and forced resettlement are also reviewed. It is discovered that, although many lessons have been learnt from the Akosombo forced resettlement, these lessons have not been effectively translated into action plans in order to undertake successful forced resettlement in Ghana. The challenges and errors in planning the Bui resettlement have therefore marred its successful implementation. This has resulted in more adverse impacts on the affected people than good ones such as infertile lands, low farm yield, poor housing structures and total ban on fishing in the Black Volta without alternative fishing grounds.

Microwave communication devices have become ubiquitous in the past decade. As an increasing number of systems compete for spectrum, guard bands have shrunk to increase bandwidth efficiency. The frequency behaviour of microwave devices is affected by thermal expansion. In order to avoid interference with adjacent bands, microwave components must exhibit high temperature-stability in most communications applications. Thermally stable materials can be used to construct temperature-stable components. However, this approach requires an expensive mass and cost trade-off. Temperature compensated aluminum resonators and filters provide major advantages in cost and mass. This work proposes that a compensating tuning screw with a temperature-dependent effective length be constructed by mounting a bimetallic compensator at the end of a mounting screw. This so-called bimetal tuning-screw can be used to produce temperature-compensated resonators and filters. There are several advantages to this approach. Compensation can be tuned by adjusting the depth of the bimetal, simply by adjusting the mounting screw. Since there are no moving parts inside the cavity or filter, and the bimetal can be plated, there are no additional sources of passive intermodulation. Also, this design is simple to implement for waveguide designs in general. In order to compensate for temperature drift, it is useful to quantify uncompensated drift. Temperature drift for a lossless linearly expanding RF component is derived from Maxwell's equations. For the lossy case, it is demonstrated that the resulting formula is approximately true, and that the quality of this approximation is excellent for practical levels of temperature range and thermal expansion. Experimental results are provided that demonstrate bimetal compensation under uniform-temperature conditions for a single aluminum resonator. Measured drift of the compensated resonator is -0.38 ppm/°C, compared to -23 ppm/°C for an uncompensated resonator. Measured drift for a bimetal-compensated 4-pole filter prototype is 2.35 ppm/°C. A method for adjusting compensation for a filter is also provided. Multiphysics simulations are used to examine power handling for bimetal-compensated filters. It is demonstrated that power-handling can be improved by reducing the effective length of the compensator to improve heat conduction to the cavity or filter.

The Financial Accounting Standards Board (FASB)/ International Accounting Standards Board (IASB) proposed Conceptual Framework solidifies stewardship as a primary financial reporting objective. Concurrently, fair value (FV) continues to be emphasized in FASB and IASB standards. In this study, using data from real estate firms in the UK, I test whether FVs provide stewardship-relevant information incremental to information provided by historical costs. Measuring stewardship by changes in CEO cash compensation and FVs through revaluations of investment properties, I find FVs provide stewardship information beyond historical costs; however, FVs must be supported by external appraisals to be useful. Further, FVs help to explain the traditional association between stock returns and compensation. The actual realization of FV changes through sale continues to be rewarded through compensation, meaning the full compensation value of FV changes is not given until realized. FV changes provide more useful stewardship information when FV estimates are of higher quality or when the CEO is more strongly governed. I also find that higher sensitivity to management effort, proxied by firm growth opportunities, makes FV changes more stewardship-relevant. Overall, I conclude that for UK real estate firms, FVs are useful for assessing management's stewardship with improvements in estimate quality and sensitivity to management effort increasing stewardship-usefulness; however, historical costs continue to be relevant for stewardship. My thesis provides insight into what information best captures management stewardship.

Sexual differentiation is a fundamental characteristic of all eukaryotes, dictating sex-specific morphology, physiology and behavior. Diploid organisms with heteromorphic sex chromosomes (XX or XY) require regulatory compensation of the X chromosome to maintain correct levels of genetic expression between the sexes, a process termed sex-specific dosage compensation (SSDC). The fruit fly, <i>Drosophila melanogaster</i> dosage compensates by upregulating transcription of most X-linked genes two-fold. Associated with this two-fold up regulation is the male-specific lethal (MSL) complex, a RNA-protein complex comprised of at least five known proteins; MSL1, MSL2, MSL3, males absent on the first (MOF), and maleless (MLE) and two non-translated RNA molecules; roX1 (RNA on the X chromosome) and roX2. The complex modulates the chromatin structure of the male X chromosome via acetylation of H4K16. MOF and MSL3 both exhibit an N-terminal chromodomain, whose function is unclear. The MSL3 chromodomain has been suggested to bind H3K36Me3. Chromodomains are a paradigm of how a single structural fold has evolved in diverse proteins to bind distinct targets. Chromodomains are common to nuclear regulators, and bind diverse targets including histones, DNA, and RNA. They function as recognition motifs of histone post-translational modifications and facilitate the translation of the histone code into a distinct local chromatin structure via recruiting the appropriate chromatin modulating machinery.<p> The goal of this research is to determine the structure of the <i>D. melanogaster</i> MOF and MSL3 chromodomains by X-ray crystallographic and/or nuclear magnetic resonance techniques, to advance our understanding of the structural characteristics of these diverse domains. Here we report the cloning and reproducible expression and purification of the <i>D. melanogaster</i> MOF and MSL3 chromodomains and their Homo sapiens orthologues. The <i>D. melanogaster</i> MOF chromodomain, whose NMR structure was published during this research, has been crystallized. Attempts to solve the crystal structure by molecular replacement, multiple-wavelength anomalous dispersion, and single-wavelength isomorphous replacement are reported.

This study investigates the relationships among corporate governance mechanism, firm performance, and executive compensation within Chinese publicly listed firms. The corporate governance structure in China is a unique combination of the Anglo-American model and the German system by including a board of director and a supervisory board simultaneously, and has two monitoring organs, independent directors and supervisory board, co-existing. One of the special features of the Chinese publicly listed firms is their close relationship with the government because most of them were converted from state-owned enterprises at the beginning of the market-oriented economic reform in China. Therefore, we attempt to explore the effects of political connections of their ultimate controllers on corporate governance mechanism, on firm performance, and on executive compensation in China. Our findings indicate a dysfunctional corporate governance system in China, which cannot bring improved firm performance but grant executives high compensations. While we take into consideration the political connections, our results show that they deteriorate corporate governance mechanism, but do not result in inferior firm performance. Robustness tests demonstrate a non-linear effect of corporate governance on executive compensation, jointly depending on the status of a firms political connection and its ownership structure.

Agency theory, proposed by previous studies such as Guidry, Leone, and Rock (1999) and Arya and Huey-Lian (2004), suggests that bonus and other accounting-metric-based compensation can motivate managers to perform well in the short horizon while equity-based compensation, such as restricted shares and stock options, can serve the purpose of aligning the long run interests of shareholders and managers. The empirical evidence, for example Jensen and Murphy (1990), Kaplan (1994), Hall and Liebman (1998), Murphy (1999), Zhou (2000), and Chowdhury and Wang (2009), confirms that incentive compensation is popular in many countries. However, recent studies suggest that the relation between performance and incentive compensation is weak. Shaw and Zhang (2010) find that CEO bonus compensation is less sensitive to poor earnings performance than it is to good earnings performance. Fahlenbrach and Stulz (2011) study the relation between bank performance during the 2008 bank crisis and the bonus and equity-based compensation of bank CEOs. They find that banks with CEOs whose incentives were better aligned with the interests of shareholders performed worse than other banks. This study examines whether ownership structure can explain the differences among compensation structures of chief executive officers (CEOs). In particular, we examine the compensation structure of three distinct groups: family-controlled, institution-controlled, and widely-held firms. We distinguish these three kinds of firms to represent different levels of market imperfection. Compared with family-controlled and institution-controlled firms, widely held firms have dispersed ownership. The most significant weakness of a widely-held ownership structure is the lack of shareholder monitoring due to the unmatched benefit and cost of monitoring for small shareholders. In contrast, a holder of a large block of shares will have the same monitoring costs but the benefits to this shareholder from monitoring management and reducing agency costs would be substantial and larger than the costs of monitoring. Thus the presence of a large shareholder will reduce the agency costs. In addition, large shareholders may be willing to spend time and effort continuously to collect more information on management performance or to estimate the firms investment projects. This behaviour will reduce the problems that arise from information asymmetry and will decrease the waste of free cash flows by managers. Both family-controlled firms and institution-controlled firms have large shareholders. However, whether or not the control shareholders are playing an active monitoring role is still an important issue. From the viewpoint of aligning the interests of managers and shareholders, the family-controlled group is superior to the institution-controlled group. First, institutions are more flexible in moving their ownership from one firm to another depending on performance. If the costs of monitoring are high in comparison to the costs of rebalancing portfolios, institutions will choose to rebalance instead of monitoring. In contrast, a family that controls a firm does not have this flexibility. Second, family-controlled firms generally assign influential positions to family members whose focus is in line with that of the family group. Even though a non family member may be appointed as the manager, the level of monitoring is significant given the high ownership concentration by the family. However, the level of monitoring by a family may not necessarily translate into a reduction of agency costs for minority shareholders. Indeed, previous studies suggest that significant family ownership may lead to agency costs of its own. The family may divert company resources for its own benefit despite the presence of a manager who may or may not be a family member. Essentially, the family and the manager can collude to spend on perks and personal benefits at the expense of minority shareholders. Chourou (2010) suggests that excessive compensation of chief executive officers at some family owned Canadian corporations may be viewed as expropriation of minority rights. Overall, the main objective of this study is to examine whether block-holder monitoring is a substitute to the incentive components of compensation. We propose that as we move from widely-held to institution-controlled the level of monitoring may or may not increase. However, as we move further into higher control, as may be suggested by family ownership, the level of monitoring will increase but this monitoring may not necessarily reduce agency costs. The results show that the institution-controlled firms pay significantly less bonus compensation per dollar of assets than widely-held firms but the differences in equity based compensation are not significant. In addition, the family-controlled corporations offer the lowest performance-based compensation, bonus per dollar of assets, in comparison to the institution-controlled and the widely-held groups. These results indicate that the family-controlled Canadian corporations rely more on monitoring managers than paying them incentive payments in the form of bonus payments. In addition, our results indicate that the institutions which control corporations may be monitoring the managers of these corporations but this monitoring does not significantly reduce the need for the long-term incentive components of compensation. This result suggests that institutions may monitor the short-term performance effectively but they may prefer rebalancing their portfolio rather than monitoring long term performance.