The major contributions of this thesis are categorized into three areas: (i) magnetic modeling, (ii) optimal performance assessment and (iii) multi-objective design methodology of the linear permanent-magnet (LPM) and linear variable reluctance (LVR) motors for manufacturing automation applications. The target application is to perform repetitive point-to-point positioning tasks on a continuous basis under temperature constraints. Through simplification, the constraint on temperature rise may be replaced by a constraint on average power dissipation, provided that the thermal resistance is constant and known. The basic framework of analysis is first introduced for a class of idealized linear synchronous (LS) motors, where magnetic saturation and spatial harmonics are neglected, to provide clarity and insight. The physics-based force models for the LPM and LVR motors, including spatial harmonics and magnetic saturation as appropriate, are then developed. Due to magnetic linearity, the force model of the LPM motor is derived from the analytical solution of the Poisson Equation. A nonlinear magnetic circuit analysis model is developed for the LVR motor that includes both spatial harmonics and magnetic saturation. The accuracy of both force models are verified by finite element analysis. Applying those force models, the optimal performance assessment of the LPM and LVR motors is explored using the mathematical framework discussed for the idealized LS motors. In particular, the relationship between travel time and travel distance is characterized in terms of average power dissipation. The performance assessment methodologies developed here may be applied to any motor technology used in manufacturing automation applications. The multi-objective design optimization problem is then defined and software for its solution is developed using Monte-Carlo synthesis, the performance assessment tools and dominance-based sorting. Design results for the LPM and LVR motors are then presented. Future research is discussed as the conclusion of the thesis.

Pulsed laser ablation (PLA) in single shot on polycrystalline Al thin foil ca. 50£gm in thickness was conducted in air and water to study the heat and shock affected zone (HSAZ) under specific wave length (532 nm), pulse duration time (16 ns) and laser input energy (400, 600 and 800 mJ/pulse) with a specified spot size of 0.03 mm2. The combined optical and electron microscopic observations indicated water is more effective than air to reduce HSAZ which increases with the increase of pulse energy yet with negligible recrystallization of Al substrate. Oxidation of the Al foil and redeposition of aluminum oxide nanocondensates on the laser incident side caused thermal mismatch between the coating and the Al substrate (especially when only 30£gm in thickness), and hence intra- and intergranular cracking along thermally etched subgrain boundary and grain boundary, respectively. The minimum interspacing of successive shots for effective fabrication of aluminum oxide nanocondesates from Al substrate are 470 and 250£gm, for the present PLA in air and water, respectively. PLA fragmentation of £\-Al2O3 powder (mainly 100 nm in size) in water was also conducted under free-run mode (1064 nm, 240 £gs pulse duration) vs Q-switch mode (532 nm, 16 ns pulse duration) having laser spot size 0.03 mm2 and focal point 5 mm beneath the water level for an accumulation time of 20 min at 10 Hz. Comparing with the case of 1064 nm, the 532 nm laser incidence suffered less water absorption and was more effective to produce nanocondensates mainly in the form of £^ and £_* derived phases ranging from 5 to 20 nm in diameter which were occasionally (111)-specifically coalesced as twinned bicrystals.

Parametric uncertainty is one of many possible causes of divergence for the Kalman filter. Frequently, state estimation errors caused by imperfect model parameters are reduced by including the uncertain parameters as states (i.e., augmenting the state vector). For many situations, this not only improves the state estimates, but also improves the accuracy and precision of the parameters themselves. Unfortunately, not all filters benefit from this augmentation due to computational restrictions or because the parameters are poorly observable. A parameter with low observability (e.g., a set of high order gravity coefficients, a set of camera offsets, lens calibration controls, etc.) may not acquire enough measurements along a particular trajectory to improve the parameter's accuracy, which can cause detrimental effects in the performance of the augmented filter. The problem is then how to reduce the dimension of the augmented state vector while minimizing information loss. This dissertation explored possible implementations of reduced-order filters which decrease computational loads while also minimizing state estimation errors. A theoretically rigorous approach using the ?consider" methodology was taken at discrete time intervals were explored for linear systems. The continuous dynamics, discretely measured (continuous-discrete) model was also expanded for use with nonlinear systems. Additional techniques for reduced-order filtering are presented including the use of additive process noise, an alternative consider derivation, and the minimum variance reduced-order filter. Multiple simulation examples are provided to help explain critical concepts. Finally, two hardware applications are also included to show the validity of the theory for real world applications. It was shown that the minimum variance consider Kalman filter (MVCKF) is the best reduced-order filter to date both theoretically and through hardware and software applications. The consider method of estimation provides a compromise between ignoring parameter error and completely accounting for it in a probabilistic sense. Based on multiple measures of optimality, the consider filtering framework can be used to account for parameter error without directly estimating any or all of the parameters. Furthermore, by accounting for the parameter error, the consider approach provides a rigorous path to improve state estimation through the reduction of both state estimation error and with a consistent variance estimate. While using the augmented state vector to estimate both states and parameters may further improve those estimates, the consider estimation framework is an attractive alternative for complex and computationally intensive systems, and provides a well justified path for parameter order reduction.

Thelohania solenopsae Knell, Alan, and Hazard is an internal microsporidian that parasitizes the red imported fire ant, Solenopsis invicta Buren. This experiment studied the invasive interactions between the native United States ant, Monomorium minimum (Buckley), and S. invicta colonies infected with T. solenopsae and S. invicta colonies free of parasites. This study utilized S. invicta colonies of 100, 300, 600, 800, and 1000 workers to determine the ability of 1000 M. minimum workers to invade each S. invicta colony size. There was a significant difference in the time for M. minimum to invade S. invicta when comparing S. invicta colonies of 1000 workers infected with T. solenopsae to S. invicta colonies that were uninfected. It was also determined that there was a significant difference in the time for M. minimum to invade smaller uninfected S. invicta colonies as opposed to larger uninfected S. invicta colonies. There was no significant difference in the ability of M. minimum to invade smaller S. invicta colonies infected with T. solenopsae as opposed to larger infected S. invicta colonies. It was therefore concluded that S. invicta colonies infected with T. solenopsae were not able to defend their colony or prevent competing ants from invading as well as uninfected S. invicta colonies. This study also demonstrated that M. minimum is a significantly more invasive species when compared to S. invicta, invading S. invicta territories in every situation and doing so in a significantly shorter period of time than S. invicta colonies invaded M. minimum colonies.

Fairness and justice are important goals and cores values for pursuing an effective taxation system. However, for certain economic and social purposes, our nation implements extensive and long period tax deductions causing constant doubt of the equality of taxation. The tax deduction policies may be equitable to the past, but with the change of the environment, should the government carefully examine whether the result of the tax deductions has affected the fairness, justice and fiscal of the nation. If these deductions have already impaired the welfare of the nation, it is necessary to revise the taxation system and reconstruct the public value. The Legislative Yuan has passed ¡§Fundamental Regulations of Income Tax¡¨ also named ¡§Alternative Minimum Taxation, AMT¡¨ by the end of 2005. It is the first tax regulations passed by the Legislative Yuan in the last two decades. These regulations limit the deductions and compensate the deficiency of unfairness. Thus, this research will focus on taxpayers¡¦ recognition and support of the tax reform after the regulations are executed. Should people promote more tax reforms if outdated deductions exist? Therefore, by combining the questionnaires with the empirical analysis, gathering related discoveries and opinions, this research leads to a practical suggestion and provides a reference with the tax authorities to amend the tax deduction policies. According to the result, the tax experts and professionals agree that AMT meets the needs of tax equality and justice. Besides, nearly 60% of the interviewees think AMT is beneficial to our nation¡¦s finance. However, people recognize that negative effects and problems with the implementation of AMT should be overcome. People also highly expect to modify the outdated tax deductions. In conclusion, our research provides the following suggestions: 1. To thoroughly review and revise the outdated tax deductions promptly. 2. To review and amend the extent of the income tax deductions. 3. The review of investment tax credit is the main purpose of our tax reforms. 4. To prevent the incentive of tax evasion and discuss regularly about the existence or abolition of the AMT.

This study constructs a analytical framework in which the Labor Union has full bargaining power and firms are heterogeneous to analyze the economic effect for adjustment of minimum wage ratio. There are two features in this model. First, every firm shows heterogeneity in productivity and survivors of the market are only those with good productivity. Second, the labor union has sufficient power to bargain wage ratio. The main findings of this study include: 1. Increase in the minimum wage ratio raises the survival threshold and labor wage ratio, but decreases the numbers of firms. 2. Increase in the minimum wage ratio does not necessarily result in decrease of labor demand.

Product miniaturization is a long-term trend. Mechanical micro-machining is a suitable technique for manufacturing of microstructures characterized by cheap equipments, less working time, and possible complex geometry. For the requirements for high precision manufacture, the use of minimum/minimal quantity lubrication (MQL) is a good strategy for micro-machining due to long tool life and high product accuracy. This study presents an experimental investigation of the MQL in micro milling. The tool wear, surface roughness, and burr formation are observed at different feeds (1 £gm/rev, 1.5 £gm/rev, and 2 £gm/rev) and cutting speeds ( 37.7 m/min, 56.55 m/min, and 75.4 m/min) under dry and MQL cutting. Unlike conventional milling, greater tool wear is observed at lower feeds. Compared with the same cutting condition for dry cutting (feed 2 £gm/rev, cutting speed 56.55 m/min), MQL can reduce the tool wear about 56%. In terms of the consumption of the cutting fluid, oil flow rate of 1.88 ml/h is sufficient for reducing the tool wear in micro milling. According to the experimental results, deterioration of surface finish and burr formation are closely related to the tool wear. The use of MQL, not only reduces the tool wear, but also diminishes the deterioration of surface finish (the improvement of Ra is at least 0.6 £gm) and the burr formation.

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Reproduction de : Thèse de doctorat : Sociologie : Lyon 2 : 2003. / Titre provenant de l'écran-titre. Bibliogr.

The Minimum Wage Ordinance was introduced since 1 May 2011. It was widely discussed among the society on how it affects the economy and the market nature of Hong Kong. Employer has carried out different measures on either changing the term of employment contract or raise up the requirement for the employee as to compensate the addition salary cost they have paid under this regulation. Being a participant in building management service, we observe that owners/ residents rise up their expectation on the performance of building attendant. They believe the increase of salary under MWO would motivate the building attendant on their work and it would also attract more candidates with higher qualification and personal ability to join the service sector. However, there is a variation between the expectation and the reality. This research is attempted to identify whether the implementation of MWO would improve the performance of building attendant and what are the factors of giving such impact by studying the change of labour market of building management and the result of customer satisfaction survey conduct in this research. From these findings, we would try to verify if there is any direct relationship between MWO and building staff performance and recommend some appropriate strategy to owners/resident on how to improve the performance of building attendant. / published_or_final_version / Housing Management / Master / Master of Housing Management