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Polymer solar cells have been attracted attention because they combine flexibility with low-cost fabrication, have been previously developed based on bulk-heterojunction. Many research groups have developed solar cells based on Poly (P3HT) and (PCBM) composites. The nanostructure morphology of P3HT: PCBM composites play an important role for affecting the device performance. Many researches propose a lot of method to improve the morphology, such as the selection of solvent in photoactive layer and the thermal annealing effect. In this research we have studied the nanostructure morphology of P3HT: PCBM composites film by blending with Cetrimoniumbromide (CTAB). We have prepared Polymer solar cells incorporating an active layer of P3HT: PCBM blended with CTAB. The short-circuit current density of the polymer solar cells improved after blend if 0.01wt% of the CTAB into P3HT: PCBM active later. The device structure of ITO/PEDOT: PSS/P3HT: PCBM: CTAB/Al was measured under AM 1.5G 100 Mw/cm2 illumination, exhibited a power conversion efficiency of 2.5%, which is a 17% improvement than the standard device. The power conversion efficiency increased from 2.13% to 2.5%. The short current density increased from 5.47mA/cm2 to 6.43mA/cm2.

The research thesis is based on the study of Kaohsiung MRT Orange Line. On condition that bilateral power is supplied during the target year, make two-minute interval as the background simulation, and use MATLAB & Simulink software for analysis tools. Through the establishment of the equivalent in the stray current model, discuss the original ground construction of Kaohsiung MRT Orange Line, and change the resistance of the track structure, in order to analyze whether that affects stray currents. Besides, simulate the maximum stray current density and its length in each station. To study cathode corrosion of underground metal pipeline due to stray current, the equivalent circuit model is applied for computer simulation. By changing the distance between the underground metal pipelines and MRT rail tracks the voltage potential of the pipe lines introduced by the stray current of MRT system is derived. The mitigation strategy of cathode corrosion due to stray current is also proposed in the thesis.

Remote field eddy current (RFEC) testing is an eddy current non-destructive test method that has become widely used for the examination of carbon steel tubes, such as those found in heat exchangers and boilers. RFEC testing relies on the use of very low intensity electromagnetic fields on the exciting probe. The defect detection is carried out considering the phase difference between the exciting and pickup signals. However, various testing effects were produced because the affection of different electromagnetic characteristics of tubes and types of defects The purpose of this study is to analyze the influential factors of RFEC testing accuracy by means of the finite element method (FEM). In order to investigate the numerical simulation, the researcher used the finite element software package FEMLAB to create an electromagnetic model of RFEC testing. Then he applied the mathematics software package MATLAB to plot the voltage plane diagram and defect-phase difference diagram. After the comparison of the simulation with experiments, the researcher confirmed the reliability of electromagnetic simulation. As a result, this study provides the variations in RFEC testing result diagrams for the influential factors. Over all, this study has successfully established an FEM RFEC electromagnetic model. After the FEM simulation, this method can provide many comparable data for experimenter. This study may remedy the different types of defects and reduce assessing error. Therefore, the accuracy and reliability of testing of RFEC can be accessed.

Eddy current testing is a non-destructive testing method, which is usually used for an examination of thin metal material. It can acquire the coil impedance variety between the eddy current magnetic field and the coil magnetic field by electromagnetic induction. By prognosticating its phase angle, testing can exam the influence of the examination through the impedance plane diagram. However, the eddy current testing is usually influenced by different types of the defects and factors of examination. The purpose of this study is to analyze the examination factors of eddy current testing accuracy by means of the finite element method (FEM). This study is to create two dimensional axial symmetry model of simplification in eddy current testing by finite element software package Femlab. After that, the researcher applied the mathematics software package Matlab to plot the impedance plane diagram and evaluation curve. Furthermore, the researcher analyzed the impedance plane diagram and evaluation curve in different examination factors. After the FEM simulation in different types of the defects and the examination factors, this study can provide many comparable data for experimentalists, to judge the condition of the defects more correctly and to reduce testing errors more effectively in the eddy current testing.

Usually, a large steam turbine-generator unit has itself a blade vibration mode that is close to its double electrical frequency. This mode of vibration will easily be excited by electrical load unbalance, thereby the turbine blades will be affected by this kind of vibrations, especially for the last three rows of blades. In fact, turbine generators operate in corrosive environment and undergo the statistical stress impact due to the randomly unbalanced currents. In this paper, the blades are subjected to corrosion fatigue, thereby small stress still may cause damage significantly. On the other hand, the damage caused by system unbalance is so small that people could neglect it usually. Nevertheless, for the long-term operation with lasting system unbalance, its influence on reliability may no longer be omitted. According to the gamma distribution in unbalanced negative phase current (I2), the probability level of fatigue life, the reliability against fatigue failure and crack growth of turbine blades are evaluated for three turbine-generator system in the paper. The blades with various materials, safety factors and stress concentration factors are considered in the simulations. The influence of extreme value distribution of I2 to the reliability is also investigated. According to the results, we have reason to believe that corrosion fatigue is one of causes that led to crack initiation or damage of blades under normal operation.

Two novel clock feedthrough compensation circuits for switched - current (SI) memory cells are proposed to reduce the clock feedthrough error. One is a current compensation first generation SI memory cell and another is an error voltage reduction second generation SI memory cell. Both circuits are designed using a 0.5£gm UMC CMOS process. In this study, the first circuit has obtained an accuracy about 0.1% error with a frequency of 5MHz, and the second circuit has achieved 0.12% error in accuracy with 10.5MHz in frequency. The results are obtained by SPICE simulates.

Thesis (M.S. in Applied Science (Physical Oceanography))--Naval Postgraduate School, December 2009. / Thesis Advisor(s): Collins, Curt. Second Reader: Margolina, Tetyana. "December 2009." Description based on title screen as viewed on January 28, 2010. Author(s) subject terms: California Current, RAFOS floats, current meters, seasonal variability, mesoscale eddies, tides. Includes bibliographical references (p. 261-263). Also available in print.

Thesis (Ph. D.)--Cornell University. / "Reprinted from the Sibley journal of engineering, Oct. 1904." "List of articles dealing with alternating-current phenomena": p. [1] Appendix.

Thesis--Ph. D., University of Hong Kong. / Mimeographed.