Flow regime transitions and the modeling thereof underlie the design of microgravity two-phase systems. Through the use of the zero-g laboratory, microgravity two-phase flows can be studied. Because microgravity two-phase flows exhibit essentially no accelerations (i.e. no buoyancy or gravitational forces), the effects of acceleration on two-phase flow can be decoupled from the effects of other fluid phenomenon. Two-phase systems on earth are understood mostly through empiricisms. Through microgravity two-phase research, a fundamental understanding of two-phase systems can be obtained and applied to both terrestrial systems in space applications. Physically based bubbly-bubbly/slug and bubbly/slug-slug flow regime transition models are introduced in this study. The physical nature of the models demonstrates a new understanding of the governing relationships between coalescence, turbulence, void fraction, boundary layer affects, and the inlet bubble size distribution. Significantly, the new models are dimensionless in addition to being physically derived. New and previous models are evaluated against zero-g data sets. Previous models are not accurate enough for design use. The new models proposed in this study are far more detailed than existing models and are within the precision necessary for most design purposes. Because of the limited data available, further experimental validation is necessary to formally vet the model. Zero-g data set qualification and flight experiment design have not been standardized and as a result, much of the data in the literature can be shown not to represent microgravity conditions. In this study, a set of zero-g quality criteria are developed and used to qualify the data sets available in the literature. The zero-g quality criteria include limitations on buoyancy forces relative to surface tension and inertial forces as well as requirements on acceleration monitoring and flow development length and time. The resulting evaluation of the data sets available in the literature unveils several experiment design shortfalls, which have resulted in data sets being misrepresented as zero-g data sets. The quality standards developed in this study should continue to be improved upon and used in the design of future zero-g fluid experiments. The use of one-g single-phase models in approximating zero-g two-phase experimental data was successfully performed in this study. Specifically the models for pressure drop, friction factor, wall shear, and velocity profile are demonstrated. It is recognized that the mixing apparatus will affect the flow regime transitions, specifically the distribution of bubble sizes that exit the mixing apparatus. Unfortunately, little-to-no information regarding the mixing apparatus used in past experiments can be found in the literature. This will be an area for further developmental research. In summary, the approach to understanding and modeling two-phase phenomenon demonstrated in this study provides tools to future researchers and engineers. Special attention to data qualification and experiment standardization provides a different prospective and interpretation of the currently available data. The physically based and dimensionless modeling demonstrated in this study can be extended to other studies in the field as well as providing a basis for the application of heat transfer modeling to microgravity two-phase systems, specifically boiling and condensation.

Coherent control of laser induced processes is based on the quantum interference among multiple excitation pathways. Progress in the field has been fueled by advances in pulse shaping techniques, allowing modulation of phase and amplitude across the bandwidth of ultra short pulses. This dissertation makes use of coherent control technique for the optimization of two-photon fluorescence (TPF) and its applications in selective excitation for biomedical imaging. Different physical processes, e.g. TPF, second harmonic generation (SHG) and their ratios (e.g. TPF/SHG) were optimized by using feedback control pulse shaping technique with an evolutionary algorithm. Various nonlinear effects, e.g. filamentation, intensity clamping and white light generation were studied using two-photon fluorescence and Z-scan technique with different dyes and biomarkers. Simultaneous measurements of different nonlinear effects were performed. Novel methods were proposed and implemented to obtain two-photon excitation characteristics in intensity-resolved manner. Understanding of these nonlinear effects can give new solution to the issues of spatial resolution and molecular contrast for cellular and tissue imaging.

Due to the increasing of substitution and competition of products, the life cycle of products is shorter than previous time and the perishable has becoming visible for service industry and other related manufacturing industries. Wrong strategy and management of pricing make many companies lose the right opportunity to invest and even trapped in the bad financial structure with the apparent character. More and more private club managers use the concept of yield management to deal with their problems and maximize their benefits because of the property of perishable in recent years. However most researchers study about ways to improve the performance and to understand the distribution of consumers¡¦ recognition instead of realizing the factors impacting the products¡¦ pricing. I will develop an initial pricing model and find out how the relationship among the factors which influence the products¡¦ pricing interacts by this model

Deinococcus radiodurans is a highly UV and radio resistant bacterium. The addition of Mn2+ could induce an Mn-CD effect in this bacterium. In this study, we used two-dimensional polyacrylamide gel electrophoresis to compare and analyze the expressed-proteins under various growth conditions, such as temperature and the presence of Mn2+ or not. The results showed that Mn2+ could affect the similarity proteins expression. As the time of Mn-CD effect elapsed longer, the similarity of the proteins from different growth phages became lower. This indicated that Mn2+ indeed could induce or repress the gene expression. From the 2-D gel analysis, there were fourteen proteins had been induced or overexpressed. Five of them were the proteins with the functions for the synthesis and decomposition of proteins and DNA, others were ATP-binding cassette¡]ABC¡^transporter¡Bsuperoxide dismutase［Mn］, and the rest five were the hypothetical proteins with unclear function. In addition, this study also found that the cultivation temperatures caused conformational and physiological modification of the cell. The addition of Mn2+ could enhance the viability of the bacterium at higher temperature.

A novel accurate calibration-based phase-shifting projected fringe profilometry (Calibration-based PSPFP) for finding the absolute shape of objects is proposed. In addition to a tremendous savings in time, the benefits of using Calibration-based PSPFP also include greatly reduced environmental vulnerability. Since Calibration-based PSPFP employs a sinusoidal fringe pattern to perform the phase-shifting algorithm, the quality and accuracy of the sinusoidal fringe pattern becomes critical. To evaluate the performance of this measurement scheme and reduce the phase error caused by projected fringes, fabrication of various digital sinusoidal fringe patterns is necessary. Thus, we propose a method to fabricate various digital patterns. Application of a 2-D fringe pattern for Calibration-based PSPFP is proposed as well.

Since long ago, the whole performance of the Taiwan¡¬s airports presents the growth tendency besides the Cargo tonnes, the passengers and aircraft movements all present the decline tendency. Compares airport extension project which Taiwan continues to carry on every year, this is implying the performance of the Taiwan¡¬s airports presents bad. This research from 2003 to 2005 the Taiwan¡¬s 18 airports as the object of study, used Two-Stage DEA to do for the main methodology, and auxiliary by Malmquist index, Mann-Whitney test, and the Kruskal-Wallis test, carried on the performance measurement of the Taiwan¡¬s airports. This research divided the airport production process into two stages (include the production interface and the sales interface), so as to set an integral model. According to the analysis, the findings showed that the Taiwan¡¬s airports, had good performance, included C.K.S. international airport, Taipei Songshan airport, Magong airport, Chiayi airport, and Kinmen airport; the Taiwan¡¬s airports, presented the growth tendency from 2003 to 2005, included C.K.S. international airport, Tainan airport, Magong airport, Nangan airport, and Lanyu airport. The site characteristics, including airport class, the airport nature, the airport position, and airport location, have the significance influence regarding the performance of the Taiwan¡¬s airports.

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The techniques of optical beam induced current (OBIC) have found wide-spread applications in characterizing many semiconductor and optoelectronic devices. A two-photon confocal microscope is adapted for investigating the dynamics of light emitting devices through the contrast mechanisms of two-photon DC and radio frequency (RF) optical beam induced current (OBIC). For comparison, the 2p-OBIC technique detects the photocurrent signal by exciting the semiconductor sample with a pulsed laser that has a wavelength below the bandgap of the semiconductor. It has high accuracy and spatial resolution. We demonstrate that the bias on the devices (forward and reverse) strongly modifies the DC and RF OBIC signals. Finally we will discuss how to explain this result, and we will provide a program to show the phase distribution of GaP LED.

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The purpose of this paper is to study the design of robust control for a flexible beam. First, the finite element method (FEM) is used to formulate the ordinary differential equations (ODEs) of the dynamic system of the beam model, and a controller is designed via the H-inf control theory. From the computer simulation results, the following conclusions could be drawn. 1. The developed controller is capable of precision positioning and tolerating external disturbance. 2. The robust stability for the system is assured. Furthermore, robust control of linear one-dimensional systems is extended here to two-dimensional systems. The finite difference method (FDM) is applied to partial differential equations (PDEs) to obtain the so-called Roesser discrete state-space model. We discussed the application of H¡Û control for two-dimensional systems and the design of H-inf controller is formulated into a convex optimization problem characterized by linear matrix inequalities (LMIs). Finally, the solutions of the LMIs are then used to construct a two-dimensional H¡Û controller.