SOI-based micro-ring resonators can be ultra-compact and highly sensitive for sensing applications. In order to obtain deeper notches and enlarge the detection area, the concentric double-ring resonators have been proposed. To further increase the sensing area and promote the sensing sensitivity, we add one more inner ring into the double-ring structure to form the triple-ring resonator. In this thesis, we have derived the transfer functions of the multi-ring structures and calculated the resonance properties of the triple-ring resonators by using the 3-D FDTD method. We have investigated the effects of the ring radius on the transmission spectra and discussed the variations of spectral response between the double-ring and triple-ring resonators. We also demonstrate the applications of the triple-ring resonator as the refractive index sensors. The triple-ring resonator can obtain deeper dips and higher detection sensitivity of 12.85 nm/RIU. Enlarging the gap can increase the sensing area and is shown to be able to promote the sensing sensitivity. Besides, the influences of the light polarization and the optical absorption on the spectral responses have been discussed as well.

In this study, the effect of synthesis conditions and annealing process on the sensitivity and stability of gas sensors made of flame-synthesized Zn-doped γ-Fe2O3 particles was investigated. Zn-doped γ-Fe2O3 particles were synthesized by flame spray pyrolysis using either H2/Air or H2/O2 coflow diffusion flames. The particles were then annealed at 325~350˚C in a tube furnace under air atmosphere. Both as-synthesized and annealed particles were used as gas sensing materials to construct gas sensors. Transmission electron microscopy (TEM), X-ray diffraction (XRD), Brunauer-Emmett-Teller surface area measurement (BET), Williamson and Hall (WH) method were employed to characterize the particles. Gas sensors were fabricated by applying the as-synthesized and annealed particles on interdigitated electrodes. The response of the gas sensor to acetone vapor, H2 in dry synthetic air was measured before and after three days of aging. High-temperature flame (H2/O2) generated nanometer-sized particles; lower temperature flame (H2/Air) generated micrometer-sized particles. Fe2O3 particles doped with 15% Zn showed the highest sensitivity. The sensors made from as-synthesized particles showed a gas sensing sensitivity that was 20 times higher than the literature value. The sensors made of microparticles lost their sensing ability after three days of aging, but sensors made of nanoparticles did not show significant change after aging. Sensors made of annealed particles (either micro or nano) did not have significant gas sensing ability, but annealing process improved the stability of gas sensors. Analysis using the WH method showed that the microstrains decreased significantly in both H2/O2 and H2/Air flame particles after annealing. The results showed that sensors made of nanoparticles have higher gas sensing signal, and more resistant toward aging than sensors made of microparticles. In addition, annealing process affected on the stability favorably due to reduction of structural defects.

As the forecasting models become more sophisticated in their physics and possible depictions of the nearshore hydrodynamics, they also become increasingly sensitive to errors in the inputs. These input errors include: mis-specification of the input parameters (bottom friction, eddy viscosity, etc.); errors in input fields and errors in the specification of boundary information (lateral boundary conditions, etc.). Errors in input parameters can be addressed with fairly straightforward parameter estimation techniques, while errors in input fields can be somewhat ameliorated by physical linkage between the scales of the bathymetric information and the associated model response. Evaluation of the errors on the boundary is less straightforward, and is the subject of this thesis. The model under investigation herein is the Delft3D modeling suite, developed at Deltares (formerly Delft Hydraulics) in Delft, the Netherlands. Coupling of the wave (SWAN) and hydrodynamic (FLOW) model requires care at the lateral boundaries in order to balance run time and error growth. To this extent, we use perturbation method and spatio-temporal analysis method such as Empirical Orthogonal Function (EOF) analysis to determine the various scales of motion in the flow field and the extent of their response to imposed boundary errors. From the Swirl Strength examinations, we find that the higher EOF modes are affected more by the lateral boundary errors than the lower ones.

This thesis proposes a methodology for determining sensitivity of building energy consumption of HVAC systems to sensor error. It is based on a series of simulations of a generic building, the model for which is based on several typical input parameters. There are a total of eight scenarios considered in this simulation. The simulation tool was developed based on Excel. The control parameters examined include room temperature, cold deck temperature, hot deck temperature, pump pressure, and fan pressure. All of the parameters considered are varied in order to analyze the sensitivity of building energy consumption to their variation. In this tool, different operation schedules for equipment, occupancy, and lighting are considered. By changing each control parameter, the sensitivity of energy use to sensor error is simulated, a regression model is generated, and the energy consumption change is expressed as a function of sensor error and outside air percentage. Two applications of this methodology are presented in this thesis. One is a SDVAV system and the other is a DDVAV system. The outside air percentage changes the trend of the sensor error curve. After the sensitivity study is discussed, some recommendations regarding the calibration intervals of the sensors are given.

Recently, the new type department stores are increasing rapidly. The competition among department stores is getting intensified. In early days, department stores usually competed with others by giving customers some discount or sending them gifts. However, the result of price war is that businesses are hard to raise their profits. This study analyzes consumer behavior by investigating the relation between store image and customer value, researching the correlation between customer value and price sensitivity and understanding the interference effects of demographics and lift style to test whether department stores can boost customer value by improving the store image and then decrease price sensitivity. This study adopts structural questionnaire to survey, Pearson Correlation Analysis and Canonical Correlation Analysis to analyze the relation between store image and customer value and research the correlation between customer value and price sensitivity, and Multiple Regression to investigate the mediating effects of customer value. Besides, in order to analyze the interference effects of demographics and lift style, this study chooses the Multivariate Analysis of Variance as testing tools to test these two variables. To understand what is the most important way for improving store image which can raise more customer values and what customer value was rose can boost more price tolerance, this study chooses the same sample, the same demographics or the same life style, to rebuild regression formulas, and identify the influence by observing the forecast variables and their coefficients. This study finds that if we choose different samples, including different ages, educational levels and lift styles, to build regression formula, the forecast variables and their coefficients would change. That is to say, if we want to increase price tolerance by raising customer value, we have to adopt different ways to different groups. In the same way, if businesses would like to raise costumer value by improving store images, they have to adopt different ways to different groups. If businesses adopt right way, they can let customer feel having more customer values so that customers can endure higher price and then reach the goal decreasing price sensitivity.

The objective of this thesis is to study the load forecasting of distribution feeders and substations for Fong-Shan District of Taiwan Power Company. To increase the accuracy of load forecasting, the load characterization of customers served has been investigated. The typical load patterns of different customers classes and derived by performing the statistic of power consumption data retrieved. The daily load profiles and load consumptions data distribution feeders and substations have been solved by considering the typical load patterns and energy consumption of all customers served. To investigate the correlation ship of temperature and energy consumption of customer classes, the temperature sensitivity of customer energy consumption has been used to update the load composition and the contribution of load change by different customer classes. To perform the load forecasting of distribution systems, the linear, nonlinear and hybrid load forecasting modules have been proposed. The historical load data of distribution feeders and substations in Fong-Shan District have been used to derive the load forecasting modules. To analyze the accuracy of load forecasting by considering the temperature effect, the temperature change is included in the load forecasting module. With the load forecasting derived, the proper load transfers among different distribution feeders and different substations have been determined to achieve the load balancing of service areas.

The bandgaps of semiconductors are decreased with increasing temperature which leads to the red-shift lasing wavelength of semiconductor lasers. Therefore, how to stabilize the lasing wavelength under different working temperatures becomes an important issue. The composition and size variation of quantum dots are additional factors which affect the lasing wavelength shift. It is well known that diffusion speeds up with increasing temperature and causes the wavelength shift to occur. To avoid the change of composition and size of quantum dots during growth, the suppression of the diffusion process is necessary to ensure the quantum dots to have a well preserved initial stage. The laser active region with InAs/GaAsN digital alloy quantum well structure was grown by molecular beam epitaxy in this experiment. The self-assembled quantum dots formed in the digital alloy quantum well under high stress. The carriers congregated in the lower energy levels with broadening distribution of composition and size of quantum dots. The peak wavelength shifted toward a longer wavelength with decreasing temperature. The behavior was contrary to the Varshni equation with shrinking bangaps under increasing temperature. Therefore, the sensitivity of the wavelength with temperature decreased. The size distribution of InAs quantum dots on the gradient quantum well broadened under higher arsenic pressure. Consequently, the wavelength sensitivity of quantum dots with temperature decreased. Finally, the InAs quantum dots were capped with the InAlAs quantum well to avoid the diffusion during high temperature growth. The capped InAs quantum dots prevented the wavelength shift from the composition and size variation of quantum dots. For the reason of stabilizing the lasing wavelength of the long wavelength semiconductor laser in optical communication system, it becomes an important topic to create new materials for the active region of the laser structure to avoid the lasing wavelength shift. The next generation temperature insensitive laser devices will be produced with the method which was created in this experiment.

Tapeng Bay is the second largest lagoon in Taiwan. The biological and ecological environments are an autotrophic system and are influenced by seasonal variability, terrestrial pollutant inputs and the exchange rates with seawater. There¡¦re intense oyster culture and fish farming activities in the bay before July, 2002. The oyster was the most important spineless member in the lagoon. They would filtrate microplankton and detritus; they would also excrete nutrient and consume dissolved oxygen. Therefore, oyster played a very crucial role in the Tapeng Bay. This study combines the biological responses of the oysters with the complicated interaction among microplankton, nutrient, detritus and dissolved oxygen to establish the relationship of dynamical mechanisms between variables by applying the system dynamics simulation software STELLA. Model results clearly reveal that the oysters are the main species of filtration. The factors which affect the biomass of oysters include microplankton concentration, temperature and individual mass; the connection between oysters and other biological variables is closely tied. The study has also shown that the removing of oysters may cause significant increases of plankton and detritus during the eutrophication condition. Although the simulated water quality variables show higher than those obtained from sampling experiments in the literatures, the trend corresponds well with the relative studies. Despite the fact that oysters excrete much nutrient and nutrient is mostly taken up by microplankton, the condition of nutrient limitation has never happened, which is in correspondence with the result. In the sensitivity analysis, the parameters of oyster filtration rate and the autotroph nitrogen to carbon ratio are important factors which have influence on oysters biomass, and the concentration of microplankton and ammonium. Oyster excretion rate and the proportion of oyster feces and pseudofeces also have significant influences on the concentration of ammonium. The oyster culture racks in the Bay have already been torn down, but the Bay is still eutrophic. This is a clear indication of the importance of the oysters in the lagoon. Properly culture some oysters in the area where exist high concentrations of microplankton or organic input. By applying the oyster abundant filtration, planktons and suspended solids, mostly detritus and organic matters, can probably be controlled and the water quality in the bay can thus be improved. Although the STELLA has its limitation on broader applications, the model developed by this study can be combined with the features of social or economic fields. A decision supporting system can be developed for the management of ecological environment policies.

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Since uncertainty exists inevitably in control systems, it is questionable whether the controller, designed to compensate a nominal plant well, still guarantees the criteria of robust stability and robust H¡Û performance for the perturbed plant. In this thesis, controller parameters tuning based on the sensitivity concept of structured singular value, called £g-sensitivity, will be adopted to do the parameter adjustment so that, when the influence of uncertainty is considered, the robust stability and robust performance properties of the nominal closed-loop system will be preserved. In view of the time consuming effect of numerical computation and the misjudgment due to discontinuity problem involved in the £g-sensitivity analysis, this thesis proposes the sensitivity concept of skewed structured singular value, called £h-sensitivity, to remedy these drawbacks. Finally, the feasibility of the £h-sensitivity based controller parameters tuning technique is verified by the simulation results of two examples.