Due to the fast expansion and development in the optical communication industry, the demand for the film quality has correspondingly increased. Ion beam sputter deposition (IBSD) achieves the lowest loss, but low throughput. In our Lab., E-beam system was used for CaO, MgO and Cr2O3 evaporation on the circumference of the Cr:YAG crystal fiber. Although the substrate was heated to around 275oC, the thin film didn¡¦t achieve low loss and high laser-induced damage threshold film. Adding ion-beam assisted deposition (IAD) system to enhance the thin film energy and packing density is the main theme of this thesis. The thesis mainly focuses on the characteristics of TiO2 and SiO2 thin film based on E-beam with IAD system. Spectrometer analyzer and Macleod software were used to calculate the refractive index and extinction coefficient. ESCA (electron spectroscopy for chemical analyzer) was adopt to measure the thin film composition of Ti, Si, O. SEM (scanning electron microscope) was used to observe the thin film quality. Low loss and high laser-induced damage threshold thin film are the goal of the present research. With optimized parameters, the refractive index of TiO2 film was achieved to be 2.51 at 500 nm, and the extinction coefficient was less than 2x10-4. The refractive index of SiO2 film can be achieved to be 1.466 at 500 nm, and the extinction coefficient was less than 1x10-4. An HR (R>99.83%) coating at 1233 nm was successfully demonstrated by the IAD deposition system.

A parametric analysis on 58 beam-column joint specimens has been conducted. The analysis considered 14 fundamental parameters in the design of each specimen and two performance indicators: the horizontal shear strength ratio between the maximum measured strength and the theoretical strength at beam yield, and the nominal curvature ductility of the adjacent beams. Each parameter was varied by a power function, while the linear correlation coefficient between each parameter and performance indicator was recorded. A combined multiple parameter analysis was then conducted to show the interaction of the design parameters and show the representative influences of each parameter based on the magnitude of the applied power functions. Two design equations were constructed from the most influential design parameters, one for each performance indicator. The shear strength ratio was found to be governed by the horizontal joint shear stress, the column axial stress and the yield strength of the longitudinal beam reinforcement. The available curvature ductility of the adjacent beams was also found to be governed by the horizontal joint shear stress, the column axial stress and the yield strength of the longitudinal beam reinforcement, but also the quantity of the horizontal joint shear reinforcement. The influence of the column axial stress on both performance indicators was found to be best represented by a quadratic function. This was because the column axial stress was found to be beneficial up to stress levels of , but axial stress levels exceeding were found to be detrimental to the performance of the beam-column joint, compared to a joint with no axial stress on the columns. The non-linear relationship of the column axial stress agreed with the design assumptions in NZS 3101 for low axial stress values, but at higher axial stress values NZS 3101 assumes a continued performance increase as a result of increasing axial stress, which has been found to be un-conservative. Additionally, an interaction between the column axial stress and the horizontal joint shear stress has been identified. As a result, beam-column joints with high column axial stress levels above 0.40 and horizontal joint shear stress levels in the order of have been shown to fail in a brittle crushing of the concrete in the joint core. Considering this behaviour, it is recommended that the column axial stress levels in earthquake designed beam-column joints should not exceed 0.35 . The results of the parametric analysis were then compared against the current NZS 3101 design equations for conservatism. It was found that a reduction in the horizontal joint shear reinforcement may be possible for beam-column joints incorporating Grade 300 steel in the longitudinal reinforcement of the beams and axial stress levels below 0.25 , but when Grade 500 steel is used or the column axial stress is greater than 0.25 , an increase in the joint shear reinforcement is required compared to NZS 3101. The current NZS 3101 design requirement of at least 40% of the joint shear force, to be resisted by means of joint shear reinforcement, has been found to be appropriate.

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A novel method of beam steering that utilizes a mass-produced Digital Micromirror Device (DMD) enables a large field of view and reliable single chip Light Detection and Ranging (LIDAR). Using a short pulsed laser, the micromirrors' rotation is frozen mid-transition which forms a programmable blazed grating which efficiently redistributes the light to a single diffraction order, among several. With a nanosecond 905nm laser and Si avalanche photo diode, measurement accuracy of < 1 cm for 3340 points/sec is demonstrated over a 1 m distance range and with a 48° full field of view.

This study sought to identify a balance test or combination of tests that would efficiently predict Olympic Balance Beam performance. Of interest, too, was the effect previous experience might have on the performance of standardized and modified balance tests. In order to determine if height affected balance performance and would therefore be an element to consider in teaching methods and progressions, the Bass Stick Test and Sideward Leap Test were raised to a height of three feet and eleven inches.